3

Newell Johnson

“The dental profession must rebalance its actions to an holistic approach to prevention of disease, which is community based and integrated with the full spectrum of medical and health sciences. A limited number of personnel with advanced training will be required for the management of existing disease. This requires fundamental changes in professional structures and in ‘dental’ education”.  NWJ January 2017 Queensland, Australia.

The professions of dentistry and the oral health of populations 1953 to 2017, with focus on countries of the British Commonwealth of Nations

Undergraduate education

I entered the dental school of the University of Melbourne in February 1956[1], having gained a scholarship from the Australian Commonwealth Government based on good results from the “matriculation” examination at the end of 6 years of secondary education at University High School: a State [ie public] school sitting opposite the University campus, with high academic standards. I remember my Physics teacher being disappointed in my career choice: he thought I was capable of better things!

The School was dominated by the physical and intellectual presence of Professor Sir Arthur Amies.  The first two years were traditional and very academic: lectures and practical classes in zoology, physics, chemistry, then anatomy, physiology and biochemistry in second year, on the main campus mixing with students of every disciple: a very important education in itself. First contact with dentistry was in the form of materials science and comparative dental anatomy, in which we learned the evolution of dentitions and memorized for the examinations the dental formulae of every branch of the animal kingdom. I cannot say that knowing the dentition of the aardvark or the wombat contributed much to my subsequent clinical practice, but this, and the zoology in particular, made me a better biologist throughout my career. Dental Materials as a discipline was well taught by Allan Docking, a sound basic scientist, then Director of the  Commonwealth Bureau of Dental Standards, and a contributor to many patents and advances in our materials [eg: Docking 1970].,

We then spent three years in lectures and practical classes in traditional silos: general medicine, general surgery – both well taught in large public hospitals – general pathology [including much diagnostic work and time at autopsies], dental anatomy, oral histology and embryology, conservative dentistry, dental prosthetics, orthodontics, oral pathology [far too late], and oral surgery. I don’t think the School regarded oral medicine as anything distinct in those days. One was left to oneself to integrate these disciplines: some did, some didn’t. What was missing? Clearly behavioural and population sciences in any depth.

We knew little of population needs at home: most people had some holes in their teeth which needed plugging with amalgam; most adults had missing teeth which needed replacing with [mostly] plastic prostheses. We got good at that, in my case and that of many of my peers, later exploited in the British National Health Service for lots of pounds sterling! Furthermore, given that at the time Australia as a society was only at the beginning of looking outward and, in time, coming to regard itself as part of a global mankind, we knew even less of the needs of “underdeveloped countries” immediately to our north and east.  It was the age when a wedding present could consist of total extractions and full dentures to avoid future problems!! Nevertheless I remember one part-time teacher, John Jago, a paediatric practitioner who was a community thinker and who went on to develop the discipline to good effect in the University of Queensland. One of his [much] later papers was with our co-conspirator here, Lois Cohen [Cohen and Jago, 1976]. Population health has become strong now in most of the ANZ schools and I particularly admire what John Spencer and colleagues did, and continue to achieve,  at the Australian Research Centre for Population Oral Health [ARCPOH] at the University of Adelaide [http://www.adelaide.edu.au/arcpoh/], and Murray Thompson and his team at Otago [http://www.otago.ac.nz/sjwri/index.htm].

Today’s students would be amazed at the rigor of our final examinations: over several weeks we wrote three-hour formal essay papers in every clinical discipline and the practical examination took days for each discipline: for “conservative dentistry” this involved my destroying much sound tooth substance: two MOD gold inlays, direct wax patterns, investment, casting, insertion, finishing [they were very shiny at least]. For prosthetics: construction of full upper and lower dentures in acrylic, including all laboratory work. Two cases in theatre involving multiple extractions under general anaesthesia: for one case we were the surgeon; the anaesthetist for the other!! If we passed the degree, we were automatically legally registered to do anything the law permitted in the State of Victoria [which then said that the practice of dentistry was “what dentists did”], so we did almost everything, without further supervision!

At that time there were 5 dental schools in Australia [there are now 12, depending on how you define a dental school, for a population of 10.3 million in 1960; 24.5 million in 2017], in the “sandstone universities” of the major cities Brisbane, Sydney, Melbourne, Adelaide and Perth: one in New Zealand, all with very similar educational approaches, based on the historical British model. Indeed these schools were inspected by the General Dental Council of the United Kingdom for accreditation, a practice which increasingly rankled we colonials and ceased after Britain joined the European Union in 1973, and the freedom of movement of professionals across the EU came into force: ANZ had to go their own way. The school I helped establish in 2004/5, and the 5 sandstone schools are all strong in research today, 5 of these [including I am proud to say “my” Griffith University], have achieved grades of “above world average” in the Australian Government quality assessment process [http://www.arc.gov.au/era-outcomes-2015#FoR/110]. Teaching is, however, under stress because of under-resourcing, the financially uncompetitive nature of academic careers v private practice. Let me also say that I am proud of my alma mater where research has always flourished and pay particular tribute to the oral microbiology and molecular sciences lead by Eric Reynolds [www.oralhealthcrc.org.au/], inter alia discoverers of casein phosphopeptide-amorphous calcium phosphate remineralising compounds, now extensively marketed worldwide

In the wider geographical area, as members of the British Commonwealth, dental schools opened in Fiji and in Papua New Guinea. Suva Medical School was established in 1885 and students given lectures in dentistry from 1931. In 1945 a two year clinical dental programme was added and from 1968 a four year clinical diploma in dentistry was available after a year of basic sciences. The school has had its ups and downs, including a partnership with the University of PNG, which also had periods of difficulty and closure. In 1993 a new approach to the training and education of oral health personnel was introduced at the Fiji School of Medicine [Tuisuva, Smyth and Davies, 1995]: Courses of study were designed to enable dental personnel to proceed through a sequence of educational modules on a career path leading from a dental assistant through dental technologist, dental hygienist and dental therapist to a dentist with a university degree.  This stepped model of education and training for members of the dental team is attractive: it allows selection of the more able and/or more committed students to attain progressively higher levels of qualification and provides a career path. I have advocated this model in the past, but attaining the right balance of numbers of each professional for a particular population is difficult, and “inflation” up the “prestige” scale can unbalance the type of providers available: it may however be applicable in low income or other underserved communities now. In my opinion it is a model worth further experiment.  Currently a wide range of health disciplines are taught in a merged institution, the College of Medicine, Nursing and Health Sciences of Fiji National University [http://www.fnu.ac.fj/college-of-medicine/] which though still supported by Australians and New Zealanders, and a growing number of their own graduates, is growing in stature.

PNG is a litany of difficulties.      I have lectured there. It currently has a too small staff of very competent colleagues. There is growing private practice in the cities but the dominant service is via an under-resourced and widely scattered government employee service. A recent restructuring of the health services [familiar to many readers I suspect: if a service is under stress, reorganize it at management level without increasing the sharp end!!] put the one and only fully qualified oral and maxillofacial surgeon in the country as Chief Dental Officer with the role of managing all dental public services, many in the most remote locations: this in a country with, according to IARC, the highest incidence of oral cancer in the world. An impossible situation and I admire Matupi Apaio for his conduct of it.

The Philippines has followed the US model, with probably too many dental schools. SE Asia has also followed western structures, but has very few institutions and they struggle: pace Cambodia and Laos. The schools I have visited in Vietnam and Thailand and Malaysia are solid, traditional in some ways, innovative in others and there are a growing number of private institutions in the mix. Some, eg have innovative curricula and are active in education research [eg the International Medical University [http://www.imu.edu.my/imu/] which partners with medical and dental schools in UK and Ireland, Australasia, Canada and China for parts of the curriculum]. The SE Asian Association for Dental Education is a vibrant body: better than many regional branches of IFDEA and IADR [www.seaade.org].  There is a nice sense of co-operation in the region: In order to develop the oral health resource capacity among the Mekong River Region countries, the International Dental Collaboration of the Mekong River Region (IDCMR) encompasses dental education institutes in Cambodia, PR China, Laos PDR, Thailand and Vietnam. They conduct regular congresses the content of which, in my opinion, are too focused on interventions. Indeed I was a guest speaker at a major meeting in Vietnam. I spoke on oral cancer and was one of the few who emphasized biology and prevention. Most were hi-tech “restorative” topics. The trade stands were dominated by dental and other implants: “other” included a major attempt to sell silicone and related breast implants! It is unfortunate that in so many low and middle income countries the focus of the practicing profession is on offering expensive treatments to the middle and upper classes, with a strong profit motive.

The single dental schools in Hong Kong and in Singapore are amongst the best in the world in both problem-based learning approaches and in research. They also have amazing physical and financial resources. Indeed, with the many caveats around the criteria used for international university rankings,  the QS rankings  for 2016 [https://www.theguardian.com/higher-education-network/2016/mar/22/qs-world-university-rankings-2016-dentistry] has Hong Kong as number one on the World, Peking University at 16 and Seoul National University at 27. Malaysia has a range of quality: it is in danger of copying the “Indian disease” [so too Colombia, Brasil and quite a few other countries]: viz: too many new dental schools; particularly those private for-profit organisations.

Which brings us to the Indian sub-continent. Sri Lanka has only one undergraduate school at the University of Peradeniya: a British Colonial establishment which is now modern and progressive in almost every way. It has an outstanding staff. In the past decade I have provided, at Griffith University, training for new consultants in Community Dentistry [Prasanna Jayasekera, Hemantha Amarasinghe; Roshnal Perera; Surani Fernado; Pradeep Jayashantha, Sanjeewa Kularatna] and had Roshnal, Surani, Sanjeewa and Manosha Perera as PhD students [see, for example, Amarasinghe et al, 2010].  This, together with decades of joint work with DYD Samarawickrama and Saman Warnakulasuriya, and many visits to the school and doing field research there, gives this country and this school a special place in my affections.

There are lessons in having only one, or very few dental schools in a nation!

Bangladesh, Pakistan, and Myanmar have traditional British colonial style institutions with good people, mush disease and a struggle for resources.

Which brings us to the disaster of dental education which is India. More than 25,000 new dentists are joining the health workforce in India each year, thanks to the over 300 dental colleges whose number has increased five-fold in 25 years (there were 55 dental colleges in 1990) while the population of the country has not even doubled in that time. More than three quarters (86%) of these dental colleges are run by private organizations and these are concentrated in urban areas. This rapid growth has unfavourable effects on the quality of dental education in India.

A further significant issue with dental workforce in India is unequal distribution: dentists are concentrated in urban areas where the dentist-population ratio could be as high as 1:4000. The current overall dentist to population ratio in India is approximately 1:10,000, and, although less than in developed countries, this is expected to reach 1:5000 by 2020. Further, most dental practices (95%) are private, and dentistry has never been a part of the public health care system in most States of India. It is highly unlikely that increase in dental manpower alone will improve the oral health of the nation.

Salaries offered by Governments, charities and many private providers for dentists with undergraduate education are in the range of 120-150 USD per month, less than that earned by many unskilled and semi-skilled workers. The option for fresh graduates to set up a private practice involves considerable financial investment with no guarantee of returns, as most urban and semi-urban areas where patients are able to pay are already saturated. Many dentists in India undertake postgraduate study, often in the hope of increasing their marketability in private practice. The number of dentists graduating each year with postgraduate and specialty qualifications is currently about 5000, but their financial and career challenges remain uncertain after spending 8 years of their life in dental education. Career options for dentists with postgraduate education are private dental practice (already saturated) or teaching positions in dental colleges (also saturated). This has led to considerable pressures of attempted migration to developed countries like Australia, UK, Canada and the USA, where substantial barriers exist, requiring dentists with Indian qualifications to sit for a series of examinations in order to practice: further, even these countries are becoming saturated. We have tried to air these concerns in the wider health literature but cannot attract the interest of editors, a matter symptomatic of the challenges we face as a profession. The best we could manage recently was a letter in the British Dental Journal [Kumar and Johnson, 1916].

The first step towards effective manpower utilization should be focused at controlling the growth of unessential manpower by withholding permission for new dental colleges and closure of those institutions with inadequate infrastructure and staff, especially those in urban areas. Secondly, prevention of oral and dental diseases must be integrated into the rest of medicine and health promotion.  Thirdly, dentistry should become made a part of the public health care system; this would provide opportunities to many dentists and free treatment to those who cannot afford to pay. School dental services should be established as schools are ideal places for primary prevention programmes. This way both the burden of oral disease and excess workforce can be tackled.   A real reduction in rates of oral cancer and of the common dental diseases of caries and destructive periodontitis can only be achieved by enhanced primary prevention. A serious debate on promotion of oral health in India needs to take place involving all health professions and the wider public: this should not be left to the dental profession alone, for its current direction seems inappropriate.

It is outside my brief to cover South America, but the many dental graduates in Brazil doing menial jobs is legendary. As we meet in Medellin, I sidetrack to note that Colombia is a striking example of what should not happen. The number of University dental programmes has grown from 6 to 36 over the past decade, apparently teaching on the traditional interventionist US and European model [although some have modern approaches to pedagogy and courses on community dentistry]. This is leading to unemployment of graduates and there is no evidence that public oral health has been impacted in any way.

In Anglophone Africa most of the schools are traditionally British in structure. Graduates seek to practice in the cities to the upper classes. Public health is underfunded and undermanned. I recall mornings on the outskirts of Nairobi, Kenya; of Ibadan, Nigeria and of the Cape Flats in South Africa where a queue of scores of patients in pain awaited the opening of public clinics, many having walked through the night to attend. And the highly motivated dentists who worked there were absolute wizards at exodontia: that in itself is a manifestation of failures in public health. [In part we used these clinics to brush up our own skills and for undergraduates from London where I was then employed to develop their skills on exchange programmes]. In 2002, I was part of the WHO Consultative Meeting: New Approaches in Oral Health Training and Education in Africa [Hobdell et al 2004]. Present were, we think [for who knows all in strife-torn and remote parts of that great continent] heads of most dental teaching institutions in the whole of Africa, including some Arabic, Francophone and Portuguese speaking nations.  A subsequent meeting in Nairobi in 2004 also had many national Ministers of Health or their representatives. All was fraternal, convivial and optimistic. We formed [we hoped] an African Association for Dental Education, elected officers and set up a virtual network to share resources [Hobdell et al 2004]. Whither? Clearly little has changed.   Our work on the important relationships with socio-economic status [Hobdell, Oliveira et al 2003] meshes with this and with our approach to the new Global Goals for Oral Health: no absolute numbers but improvements proportionate to current status and resources [Hobdell et al 2003]. In the decade and a half  since these initiatives, our friends in Africa continue these arguments [Naidoo et al 2015] and the IADR studies on Global Oral Health Inequalities [Sgan-Cohen et al, 2013 and the background papers referenced therein] and the establishment of the Global Oral Heath Inequalities Research Network [GOHIRN: http://www.iadr.org/i4a/pages/index.cfm?pageid=4473#Network], as well as the new FDI Strategy [Glick et al, 2012] seek to carry the movement forward. But how?

And now to the Mother country itself: what of Britain and Europe?

In the post Brexit vacuum there are unknowns. In summary, over the past 50 years, the number of UK schools has grown from 15, by both mergers and new establishments to 18. The new schools in particular, but really all, have embraced integrated, problem based learning, have outreached to the community in teaching, training and service and have benefited from an influx of academic staff from overseas, particularly Europe. Peninsular Dental School is an excellent example [https://www.plymouth.ac.uk/schools/peninsula-school-of-dentistry]. Aberdeen has been under resourced and has experienced controversies [http://www.bbc.com/news/uk-scotland-north-east-orkney-shetland-31501837] but as all Deans know, there but for the grace of God we may all go. The European initiatives on dental education have led the world, in my opinion, and the European Journal of Dental Education is the global leader in the science and practice of dental education these days. The DentEd programmes are full of wisdom, but there may be problems ahead with too much harmonisation of dental curricula across Europe, and the accompanying inspections [http://www.adee.org/visitations]. We must celebrate diversity whilst maintaining minimum standards. Also, this could be counter-productive to my proposals to restructure dental education into teams, with much of the more advanced learning as postgraduate qualifications after education in broad clinical methods, including general medicine: harmonisation may entrench the present system. The old southern European stomatologist system had much to recommend it in terms of treating the mouth as part of the body, though it was of course deficient in coverage of restorative and “technical” dentistry.

Within the UK the system of governance and quality control is exercised, mostly positively, by policy documents [GDC] and by inspections of both teaching [http://www.qaa.ac.uk/search-centre/results#k=dental schools] and research quality [https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/541338/ind-16-9-ref-stern-review.pdf].  The workforce has been supplemented by continental citizens of the EU, as with the whole of medicine, to the benefit of the NHS and the public, although the inevitable tensions over language comprehension and different clinical approaches have been manifest. In spite of all these initiatives and [over?] regulation, public oral health is not improving to the extent needed. There are wide disparities in oral health and access to care: eg much publicity currently revolves around caries levels in children: While there has been a significant decline at a national level, there is much regional variation. In the North West of England, a third (33.4%) of 5 year olds suffer from tooth decay; a fifth (20.1%) in the more affluent South East [https://www.gov.uk/government/news/tooth-decay-among-5-year-olds-continues-significant-decline; May 2016]. With similar differences by SES, oral cancer incidence rates are projected to rise by 33% in the UK between 2014 and 2035, to 20 cases per 100,000 people [http://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/oral-cancer/incidence]. We know the major causes. We should be capable of acting to prevent.

There is never enough money for a totally “free at the point of care” public health service, and this worsens as the population ages. On the positive side, recent governments have been willing to take actions such as a tax on sugar containing beverages, promoted mainly as a defence against childhood obesity [https://www.gov.uk/government/news/soft-drinks-industry-levy-12-things-you-should-know].

Dental therapy programmes in the Region

It was New Zealand which first introduced this cadre of oral health professionals during the First World War. With the usual caveats about the accuracy of Wikepedia, the site https://en.wikipedia.org/wiki/Dental_therapist  gives a concise description of the history since, with perhaps 30 countries in the world now having this or a similar cadres. It is increasingly common for teaching institutions, not always associated with dental schools, unfortunately, to provide training [recognising that training is different from education!] in dental hygiene as well as dental therapy, graduates being then known as oral health therapists.   The early approach was interventionist, and resulted in overtreatment, but most countries now have a strong emphasis on prevention and family care provided by this cadre. The global situation was analysed by Nash et al [2014].  Several states in the USA have dental therapists [all have hygienists], and extending their availability and their role is causing immense current controversy, with strong objections from the conservative wing of dental professional organisations. The current status is set out by Mathu- Muju et al, [2016]. America it will keep coming!

In Australia the book by edited by Tsang [2014] details the history, including our chapter [Short et al 2014]. We thought we were avant garde with an integrated programme in dental technology, dental sciences and oral health therapy at Griffith University. I have commented elsewhere on my unhappiness at its discontinuation. Oral health therapists could, in my opinion, be the backbone of the future delivery of oral disease prevention and management on a community/population basis within the oral health care teams of the future and could form part of ladder of qualifications for those interested in a career involving the prevention and management of oral diseases.

My first postgraduate qualifications

Masters degrees of 2 years full time equivalent education were available at the time I had my first degree, from most universities in ANZ, the disciplines on offer depending on staffing levels at the time. These led to specialist qualifications, were therefore predominantly clinical in nature, and largely taught by specialist private practitioners attached to the universities part time. This was, and remains to this day, a mixed blessing: excellent and pragmatic clinical teachers; little or no time or motivation for research; specialties sit in silos.  Upon graduating BDSc in 1960, I was very interested in dentistry as a biological discipline, so after a baptism of fire as a general dental practitioner in a country town in fairly remote Eastern Victoria for a few months, I went full time to the Department of Pathology in the University of Melbourne. It was technically possible to do a Masters’ by research, and I was the first to do so. Two mentors were critical: Henry Atkinson was Professor of Dental Prosthetics, an outwardly dour but internally sparkling Mancunian who had migrated to the sunshine. He had true scientific intellect, stimulated me to ask questions, and paid me as a “demonstrator” in his department whilst I researched in the Path Department. Henry was for decades historian of the profession and curator of the intriguing museum in the Melbourne Dental school which is worth a visit from any colleague in that now modern, civilized and very cultured city. Henry died in January 2016 aged 103 and a half [http://www.legacy.com/obituaries/name/henry-atkinson-obituary?pid=1000000177272555].

For my MDSc, my supervisor and mentor was Tony [Elsdon] Storey

By the way the title of my thesis was “Tissue reactions to some implant materials”. This was in pursuance of my biological interests and my then home in dental prosthetics [Johnson, 1963]. Use of endosseous dental implants goes back thousands of years to Egyptian and Mayan civilisations, and I recall wading through heavy volumes of Index Medicus, in print, in the old dental school library in Spring St, Melbourne, to summarise it all for my thesis.  At the same time, Per Brånemark, yet another remarkable Scandinavian scientist, began the global explosion of implantology: He was treating patients with titanium implants from this time in the 1960s. [To jump ahead, and to my surprise for I had become skeptical of the rush by so many dentists to use the technology, often without adequate training, I found myself re-engaged with the design of dental implants over four decades later when, as newly arrived Foundation Dean of Griffith University School of Dentistry and Oral Health [DOH] in 2005, I became joint supervisor of a PhD student the School of Engineering. This was a remarkably productive liaison [see our current paper: van Staden et al, 2017]. I am proud to record that Griffith DOH, led by Saso Ivanovski, has gone on to develop a strong programme of teaching and research in oral implantology, with emphasis on basic cell and molecular biology [eg:  Farag et al 2017]. Appropriately and intelligently planned, oral implantology is clearly a major advance in dentistry. But of course it will do almost nothing to improve public oral health at large].

During this period I was/we were the first in the world to note the discoloration of teeth by tetracycline antibiotics and we conducted a series of animal experiments to demonstrate the phenomenon, which has subsequently lead to its widespread use as a marker of the calcification front in bone and dentine, and to the need to avoid administration of this family of antibiotics to children during tooth development [Harcourt, Johnson & Storey, 1963].

Tony Storey was thus another significant mentor. He had an international reputation as an experimental pathologist, especially in bone metabolism and dysplasia. I remember him rejecting my first paper 11 times before it satisfied him for submission. My own PhD students will recognize this in me, now. He was also a qualified orthodontist and, as such, a wonderful example of a scientist who pursued the basic mechanisms of his clinical work [Storey, 1975].   He went on to be Dean of Dentistry in Melbourne: innovative and controversial.

Next steps: Falling towards England

(Clive James 1963)

Like many of my peers I wanted to see the world, and we knew we could make money on the British NHS. In my case this was to be a means to the end of further education. I knew I wanted to continue my academic career but felt I should have a strong clinical training in addition to the experimental pathology I had been doing for three years. I made 23 individual flight sectors between Melbourne and London in 1963, backpacking in Indonesia, Singapore, Malaya, Burma, India, Afghanistan, Iran, Israel, Italy and Belgium. I learned much.

I arrived in the UK with an Australian degree which at that time gave me full registration as a dentist there. I worked part time in a series of practices to fund the course for the Primary FDSRCS examination, living in the Nuffield College of the RCS in Lincoln’s Inn Fields. This was pure magic: living away from my parents’ home for the first extended period in my life in “swinging London”: King’s Road, Carnaby Street, The Beatles; music; theatre; pubs; falling in love……..

And extremely stimulating teaching. Applied anatomy came to life with Last and Stansfield [I enjoyed it for the first time because it made sense and was brilliantly taught]; physiology and biochemistry were fascinating; pathology with Walter and Israel. Many will know their textbooks and some have benefited from their face to face teaching.

I was then offered a job as a Lecturer and Honorary Registrar in dental prosthetics in the then undergraduate dental school at University College London [at that time nothing to do with The Eastman]. I guess the most important influences on me there were the Dean, Arthur Profit, and other more senior staff, particularly Robin Powell, an Australian periodontist who was a true biologist from whom I learned much about clinical periodontics and oral medicine – and about living fully in a vibrant city. Robin later went back to his native Brisbane where he advanced academic periodontology considerably, encouraged research including the then youngish Greg Seymour, later a dominant figure in global [oral] immunology.

So with FDSRCS [Eng] under my belt my thirst for research once again floated to the top. I scanned the literature for research active dental schools in Britain and homed on the University of Bristol where the legendary Arthur Darling was Director of a Medical Research Council [MRC] Dental Research Unit, focused on understanding dental caries. I took myself off to meet Darling and asked him to give me a PhD place. He did. My main Supervisor for my PhD was David Poole, a gentle, wise and kind scientist with a background in zoology. Darling was, as most will know, the generator of much of the use of polarized light microscopy for understanding the structural changes in enamel as part of the caries process, and discoverer – or at least promoter – of the relatively intact surface layer [sometimes called the Darling layer]: of considerable significance because it promoted the recognition of remineralisation and the caries process as dynamic, with periods of repair alternating with destruction.

My thesis was on the ultrastructure of the caries process in enamel and dentine. I learned electron microscopy in the Unit. I suppose the greatest contribution was observation of channels of demineralisation in enamel along prism boundaries, where enamel crystallites abutted each other at acute angles [Johnson 1967], and a little later the morphology of demineralisation and remineralisation in dentine in advance of bacterial penetration and the laying down of reactionary dentine: recognition of vital, cell mediated defense reactions in dentine. [Johnson, Taylor and Berman, 1969]. Such concepts have profound clinical importance. Teeth have a capacity to defend themselves against injury and disease and management of an established carious lesion must harness these defence reactions.

First and last postdoc!

            With a new wife and family I was choosing between an academic job back in Melbourne or a position as electron microscopist with Unilever Dental Research [very active in research into oral biology in those days] when I noticed a small advert in The Times of London for Reader in Experimental Pathology at the London Hospital Medical College [LHMC: part of the University of London] in the East End. I applied and was successful at the young age of 29. I was at LHMC one way and another for a quarter of a century, 1968 – 1993, succeeding Loma Miles as Professor and Head of Department in 1976. Loma was perhaps the most significant mentor and friend of my whole academic life. A true, true scholar: deeply interested in biological and physical sciences, in the philosophy and history of science; an innovator in educational principles and practice. He ran Archives of Oral Biology for years to an immaculate standard and was a fierce Curator if the Odontological Museum at the RCS England [and of John Hunter’s specimens]. Just one reference to place his scholarship in history: he worked assiduously to update and reproduce Colyer’s “Variations and Diseases of the Teeth of Animals”, published by Cambridge University Press. ISBN 10: 0521544076 ISBN 13: 9780521544078.

In the department were Ian McKenzie as a PhD student [whose distinguished career as a researcher of stem cell biology continues to this day in USA and UK]; Chris Squier [[who engendered in me a continuing interest in mucosal biology and we wrote the first little Monograph on Oral Mucosa [Squier, Johnson and Hopps, 1976] – and whose distinguished career as a cell biologist and academic manager in the USA continues]]; and later Ros Hopps, Margaret Scragg, David Williams and Peter Morgan [who continues as a pathologists’ pathologist at KCL].

During the period 1968 – 1983 I learned diagnostic oral pathology on the job and ran that clinical service to busy clinicians. Inter alia, this sparked a profound interest in oral oncology [one reference only from that time because I egocentrically believe that this was prescient in considering inflammation and host responses as key to the aetiopathogenesis of carcinomata: Johnson 1976] which field is, perhaps, that upon which my reputation now mostly rests.  We introduced the MSc degree in Experimental Oral Pathology; I designed and taught integrated [with all relevant disciplines] courses in Cariology and in the wider topics of Oral Pathology. Our Textbook of Cariology was one of the first in the British approach to dental education, although Scandinavians had recognized the need for such an integrated and focused approach for many years and there were several texts of USA origin. Written with my fellow PhD student at Bristol, then also at LHMC, Leon Silverstone [a paediatric dentist by then, whose star rose high in cariology and crashed dramatically a few years later in the USA], Jeremy Hardie [a “properly trained” microbiologist, though many have come later], and the solid and sensible biochemist, Tony Williams, this was published in several languages [Silverstone et al 1985] and served its purpose to be surpassed by the inestimable editions of Fejerskov and Kydd [2015].

I supervised MSc projects and PhD theses [PhDs included: Experimental repair of dentine: DYD Samawickrama; Forensic bite-mark identification: Duane DeVore; Inflammatory cell dynamics: David Williams [[Williams and Johnson, 1976] who went on to become dental Dean, a medical Dean, President of IADR and still continues as an active politician in international health]]; crevicular fluid markers of periodontal breakdown: Jonathan Pedlar; cytokine dynamics in skin and mucosal inflammation: Ania Korszun; The origin of osteoclasts from macrophages: Sue Tinkler.

During that time we were joined by Ole Fejerskov to learn electron microscopy of hard tissues from me [Fejerskov et al, 1974] and polarized light microscopy from Leon Silverstone. That was the beginning of a life-long friendship. It surprises me that after over half a century as debating partners, we have only published three papers together.

I have been an active member of the Royal Society of Medicine since 1963 and was President of the Section of Odontology in 1990 and again in 2004. In the early years I sparred in question time after lectures with another young upstart, one John Greenspan, whose contributions to oral pathology and HIV diseases is unsurpassed. It is pleasing to note that “one of ours” became Director of the largest AIDS research programme in the world at UCSF.

The impossible appointments

            In 1983, when I thought the largest department of oral pathology in the UK was motoring nicely at LHMC, I was invited to simultaneously take the Nuffield Chair of Dental Sciences at the Royal College of Surgeons of England on the retirement on Bertram Cohen, AND to start a new Dental Research Unit for the Medical Research Council. Many said this was an impossible load – and it probably turned out to be so – but we achieved a great deal. I chose to base the MRC Unit at LHMC and to devote the work to periodontal diseases – in the plural – attempting to merge epidemiology, clinical diagnostics, microbiology, biochemistry and host response [immunology]. Significant members of the team, with important contributions to knowledge then and since, included Mark Wilton [later professor of Periodontology in Cardiff]; Michael Curtis [now Dean at “The London”]; Gareth Griffiths [later Professor of Periodontology in Sheffield]; Jonathon Sterne [a raw, bright, mathematician who continues a distinguished career as a biostatistician]. When I left the Unit after 10 years Michael continued to lead the team and continues to make important contributions to microbial pathogenicity. Roy Gillett was a stalwart science manager who made original contributions and went on to found a successful private consultancy firm.

During the days of the MRC Dental Research Unit, Periodontal Diseases Programme, Bo Danielson joined us from Aarhus, to perform laboratory analyses of samples from his experimental gingivitis studies.  Firoze Manji has described these studies in detail in his paper for this Symposium. Bo showed that the tissue responses were not dependent on plaque volume, and were more dependent on the ability of the tissues to recover from inflammation, than to any site specific susceptibility. In the MRC Unit we studied the serology of antibody responses to the then fashionable periodontal pathogens throughout the phases of plaque accumulation and removal [Danielson et al, 1993].  The variability and individuality noted in the host response to potential pathogens have important implications for attempts to use such measures for establishing a diagnosis or prognosis for the individual patient [see Manji, this symposium].

At the RCS there were two progammes in existence: one dealing with oral pathology, including oncology, based at RCS headquarters in Lincoln’s Inn Fields, central London and that on research towards a vaccine for dental caries at the RCS research farm in Kent [Russell and Johnson, 1987]. Key distinguished colleagues here were Peter Morgan [again] and Saman Warnakulasuriya [who later came with me to KCL and has been outstandingly productive in oral medicine and oral oncology to this date]. Together we founded the WHO Collaborating Centre for Oral Cancer and Precancer which has been very influential.

For most of this period I was active in the affairs of the FDI World Dental Federation. Member and Chair of several working groups and Vice Chair of the Science Commission. We wrote and approved numerous policy documents and Policy Statements, drawing the evidence base together to recommend approaches to disease prevention, accurate diagnosis and management. I worked mostly in the areas of oncology [[including a series of six papers for FDI World [magazine] subsequently published by the FDI as a monograph]] and periodontology. The FDI receives a fair bit of criticism. Sure, it is a very political organisation, with its share of egocentrics, but it is a fundamentally important part of the “legs of the table” of dentistry and oral health. I define these as: i) Universities: The educators and researchers. Represented internationally by IFDEA [International Federation of Dental Education Associations]. ii) FDI: The international body of national dental associations. The practicing professions. iii) The IADR: The evidence base. Most of its huge membership is drawn from universities. iv) WHO: The governments of the world and the policy base. v). One might add a fifth strut. The dental industry. The latter is a double-edged sword. No preventative or therapeutic interventions around dentistry and oral health would be possible without them and industry has indeed contributed much to public oral health, the most notable being development and global penetration of fluoridated dentrifices. However they are industries with the primary purpose of making profits for shareholders. They encourage over-treatment and drive too much of the directions taken by the other “table legs”. These four bodies must work together to ensure public oral health. There are phases when they do better in this regard than at other times: currently it is encouraging. The current FDI list of Policy Statements is impressive and far from self-interested [http://www.fdiworldental.org/publications/policy-statements/policy-statements-and-resolutions.aspx]. There is little to argue with in the Vision Statement [http://www.fdiworldental.org/oral-health/vision-2020/shaping-the-future-of-oral-health.aspx]: the issue is actually making it happen and it is salutatory to note the following phrase within the statement itself: “Vision 2020 is aspirational and inspirational; it is not meant to be operational”. The primary authors of this document have argued for a future very like the one I would like to see [Glick et al 2016]. This is consistent with the call to action from these and other distinguished academic colleagues [Sheiham et al 2015].

That period of my career produced many publications in all three research programmes: cariology; periodontology and oncology. They are most simply grasped by reference to the trilogy published by Cambridge University Press, arising from three international meetings I convened through the Royal Society of Medicine, London, entitled “Risk Markers for Oral Diseases” [Johnson, 1991 a,b,c; Editor and contributor]. I like to believe that my colleagues and I had a major influence in shifting thinking around the world to recognition that groups and individuals were at greater or lesser risk of contracting an oral disease and that methods to identify these would both enhance understanding of aetiopathogenesis and open avenues to rational and targeted and cost-effective prevention. As I interpreted him, from numerous conversations, Aubrey Sheiham never agreed with my “high-risk” approach.!

During that period my MRC Unit joined Ole Fejerskof and Firoze Manji in field epidemiology of caries and periodontal status amongst children in rural Kenya. Really challenging and exciting field work, highly disciplined activities, rigorous emphasis on hypothesis testing. This work proved, more than anything else, [mostly thanks to the brilliant statistical brain of Vibeke Baelum: see Baelum et al 1991, 1996] that risk groups existed: most of the disease was found in a minority of the population; periodontal breakdown was not primarily related to plaque volumes, and that in the absence of dentists most of the people kept most of their teeth for most of their lives. Sadly these Kenyan data are seldom mentioned in the teachings of the University of Nairobi which sometimes expresses an outdated Western thinking: [I have been external examiner there several times].

A publication to which my group contributed was description of the associations of known cariogenic bacteria with caries experience in these Kenyan children [Beighton et al, 1989]: Our data showed significant correlations of mutans streptococci and lactobacilli with caries experience, which confirmed current dogma in the rest of the world. But in research one tends to find what one looks for, especially if the research design is weak or prejudiced [except perhaps for the Higgs-Boson particle which took decades to find: it was, of course, “there” all the time!]. Given that we now know some ~700/1000 species of oral bacteria are non-cultivable, are the associations found in Kenya meaningful?  Is a focus on mutans Streptococci and lactobacilli, as both causes and markers of susceptibility to dental caries, helpful? Is it just plain wrong given new knowledge of the human oral microbiome derived from NGS [Next Generations Sequencing] studies?

The radical re-interpretation of the natural history of dental caries and of periodontal breakdown in this African population with no access to dental care was strengthened by the extensive studies of rural populations in China and Thailand by Ole and his teams. [See the paper by Fejerskov, this Symposium],

After the impossible

In 1993 the RCS decided to invest its research resources out in the hospitals where surgery was practiced and closed their in-house academic departments. I negotiated to take a reduced Department of Dental Sciences to King’s College School of Medicine and Dentistry, from which John Garrett was just retiring as Professor of Oral Pathology. The Unit from Downe moved as a stand-alone research group to LHMC. Later Roy Russell took up the Chair of Oral Biology at Sheffield and David Beighton moved with his team to KCSMD and later to the Guy’s Hospital site on the merger with KCSMD.

I spent a decade at KCSMD in south London, as Head of Oral Pathology and Oral Medicine, and as Director of Research for the school, with teaching and research responsibilities. I inherited Gordon Proctor, whose distinguished contributions to salivary biology continue; and John Harrison as a fellow diagnostic pathologist. I became a busy specialist clinician in oral medicine, again by learning on the job, helped by Saman Warnakulasuriya who moved with me. In research we recruited Mahvash Tavassoli and continued the focus on oncology, publishing much together: Saman has continued to be extraordinarily prolific to this day.

Another new world

Being unpaid but still 100% active with research in UK and Africa and India, I saw an advertisement for the first new dental school in Australia or New Zealand for 60 years. I was interviewed and offered the job at Griffith University [https://www.griffith.edu.au/]. We moved across the globe and enthusiastically built an innovative school which was just starting degree programmes in dentistry, oral health therapy and dental technology. [My English wife commented that she always knew Newell would take a new job after retirement. She thought this could be remote, rural Africa, so was happy to settle for sunny Queensland]. It was, and still is the only school in Australia to offer a degree in dental technology, graduates of which are essential members of the oral health team [the University of Otago, in NZ, does so also]. Sadly oral health therapy has now been dropped at Griffith University. This decision was made higher up the food chain and I was not consulted. My interpretation is that this was based on financial considerations: OHTs with emphasis on prevention and interventions on children, often publically and modestly funded, did not generate sufficient income for the university. Such thinking by beauracrats has very important implications for a restructured dental profession.

I arrived as Foundation Dean at the beginning of the second intake of students: ie. a year after the school began teaching. I immediately enunciated a set of principles by which I wished to see the school develop. These are:

School of Dentistry and Oral Health

THE TEN COMMANDMENTS FOR CURRICULUM DEVELOPMENT

  1. Interprofessionality: All members of the dental team are of equal value.
  2. Community Service underpins all we do: Within course work; placements; research; clinical activity.
  3. Whole Patient and Family Care is the responsibility of every clinician. Procedure-based teaching is kept to a minimum, consistent with acquisition of the necessary range of competencies.
  4. Prevention and Health Promotion are top priorities in all courses.
  5. The School will be Research-lead ab initio. Research data and attitude will underpin all teaching. This means all academics are expected to be research active. The Workload Model will recognise that a teaching:research balance will differ between individuals, according to their skills and track records. Research into our Educational Processes is mandatory for all Courses.
  6. Evidence-based Medicine and Clinical Audit approaches underpin all teaching.
  7. Quality of Life issues are essential components of all interventions. These can be quantified and assessed. In essence this is recognition of the primacy of patient perceptions in planning and evaluating care. It encompasses aesthetics, but not slavish pandering to cosmetics and fashion.
  8. Technical Competence in treatments will be to the highest international standards, using the most modern methods and materials.
  9.  Learning and Teaching will employ State of the Art Pedagogical Approaches. This encompasses a judicial balance of traditional teaching methods with student-centered learning, and a wide range of teaching resources, including computer-aided and internet resources.
  10. Early Provision of Postgraduate Teaching is expected of all disciplines.

© Newell Johnson, Gold Coast, November 2005

This has succeeded to a limited degree and it is part of the aspirations of the La Cascada Group [“Les Six”] to find ways to improve the structure of the oral health professions and the way they are educated. I devoted myself to the School of Dentistry and Oral Health, and to the wider goals of Griffith Health and Griffith University, as Foundation Dean 2005-2009.

Retirement? What is that?

I could not give up my science, so have continued at Griffith as Professor Emeritus, 2009 to the present day. I have seven current PhD students, and many great collaborators at home and abroad. The way one gathers data at this stage of a career is to have higher degree students. This has been very productive. The focus on H&N oncology has produced field data from India, Bangladesh, Sri Lanka, Ghana, Nigeria, and Australia – and from Griffith laboratories. We have advanced models for risk factors and population screening, and devised new molecular treatment strategies [Shaikh et al 2017]. We are, we hope, at the cutting edge of defining the importance of dysregulation of the oral microbiome in the aetiopathogenesis of oral cancer [al-Hebshi et al 2017]. We are exploring new treatment strategies based on blocking the activity of HPV oncogenes with interfering rna [Shaikh et al 2017].

The program on HIV disease has derived data from Australia, Kenya and particularly South India: we have documented HHV-8 epidemiology and pathogenicity; and the circumstances where HIV itself is present in oral fluids [Speicher et al 2014].

My interest in cariology flowered again, with new work on risk factors in mother:child dyads, including epigenetic markers [Fernando et al 2015], and on maternal influences on childhood disease and behaviour [Kumar et al 2016].

I hold/co-hold two large research grants from the Australian National Health and Medical Research Council which cover the next few years of active work – with writing up thereafter. One of these seeks to prove cost-utility of preventing caries in children in remote Indigenous communities [Lalloo et al 2015 ]; the other, just awarded, to define the role of HPV in head and neck cancers in Indigenous adults in rural communities, and vaccinate accordingly.

Oral health in the region

Australia and New Zealand

Comprehensive national surveys have been held regularly in Australia. Bullet points from the latest publications [2015] of the Australian Institute for Health and Welfare and the Dental Statistics and Research Unit, Australian Research Centre for Population Oral Health, University of Adelaide, are [http://www.aihw.gov.au/publication-detail/?id=60129554382]:

  • In 2010, 55% of 6-year-olds had experienced decay in their deciduous teeth and 48% of 12-year-olds had experienced decay in their permanent teeth. After decades of decline these rates are now rising again. This is a disgraceful state of affairs for one of the world’s richest countries. [Italics from NWJ].
  • 3 in 10 adults had untreated tooth decay. Ditto
  • 3 in 10 adults aged 25–44 had untreated tooth decay. Ditto.
  • 1 in 7 people aged 15 and over had toothache in the last year.
  • 2 in 3 people aged 5 and older visited a dentist in the past year. Which is consistent with the interpretation that visits to one of today’s average dentists do not necessarily translate to oral health.
  • In 2013, approximately 19% of adults aged 65 and over had no natural teeth. The proportions were similar for females (21%) and males (17%). Of those aged 65 and over with natural teeth, nearly half (42%) wore dentures. A demonstration of emphasis on repair of damaged mouths rather than effective prevention.
  • There were about 57 dentists, 4 dental therapists, 5 dental hygienists, 3 oral health therapists and 5 dental prosthetists per 100,000 people. In my view this is the wrong balance of professional types.
  • About 1 in 2 Australians aged 5 and older had some private dental cover. Those most in need cannot afford treatment and public services are under stress.
  • Rates of oral cancer are falling for the mouth but rising for the oropharynx and are several times higher in Indigenous populations [Ariyawardana and Johnson, 2013].
  • In 2013, approximately 19% of adults aged 65 and over had no natural teeth. The proportions were similar for females (21%) and males (17%). Of those aged 65 and over with natural teeth, nearly half (42%) wore dentures.

As expected there are marked socio-economic disparities in oral health and access to care, with all State public services under stress. The decades-old School Dental service, largely staffed by dental/oral health therapists is an excellent organisation in most States and Territories, with well managed screening and preventive programmes. The benefits do not carry through life as desired.

In New Zealand the latest national survey data are from 2009 [http://www.health.govt.nz/publication/our-oral-health-key-findings-2009-new-zealand-oral-health-survey].

Key findings include:

  • Oral health has improved over time. The prevalence of total tooth loss has decreased dramatically among New Zealand adults since 1976, and adults are retaining more of their natural teeth into older age. Among children, the proportion of 12–13-year-olds who are caries-free almost doubled between 1988 (29%) and 2009 (51%).
  • However, caries remains the most prevalent chronic (and reversible) disease in New Zealand, and disparities still exist. One in three adults had untreated coronal lesions, and one in ten had root caries. There was evidence of active disease in all age groups.
  • Children and adolescents had relatively good oral health, and good access to oral health care. Overall, one in two children and adolescents aged 2–17 years were caries-free, and four in five had visited a dental professional in the previous year. Among adults with natural teeth, one in four (23%) had experienced trauma to one or more of their upper six front teeth, as had one in six (16%) children and adolescents aged 7–17 years.
  • There was clear unmet need for dental care among adults, with nearly half of adults feeling they currently needed dental treatment. In the past year, nearly half of all adults had avoided dental care due to cost and one in four adults had gone without recommended routine dental treatment due to cost.
  • The majority of adults usually used oral health services when they had a dental problem, rather than visiting for routine check-ups. People who visited only for a dental problem had significantly worse oral health than regular users.
  • In adults, poorer oral health and lower dental service attendance rates were found among men, younger adults (aged 25–34 years), Māori, Pacific peoples, and people living in areas of higher socioeconomic deprivation.
  • One in ten adults aged 18–64 years have taken, on average, 2.1 days off work or school in the previous year due to problems with their teeth or mouth.
  • About two in three children and adolescents brushed their teeth twice a day; however, less than one in two children and adolescents brushed twice daily with standard fluoride toothpaste.
  • Children, adolescents and adults living in fluoridated areas had significantly less lifetime decay than those in non-fluoridated areas, and there were no significant differences in the prevalence of fluorosis between people living in fluoridated areas and those in non-fluoridated areas.
  • Compared with Australian adults, New Zealand adults had poorer oral health across a range of clinical oral health indicators, and were also less likely to have visited a dental professional in the previous year.

South and SE Asia and the Pacific:

Space does not permit a detailed account. Suffice it to say there are vast differences in epidemiology, risk factors, genetic predispositions, public attitudes, government regulations, population-based initiatives, availability of and access to care across the region which contains countries with per capita net annual incomes ranging from the richest [eg: Singapore at World Bank rank number 5] to the poorest [eg: Lao PDR at number 152: http://lpi.worldbank.org/international/global/2016]. In all countries, it is the interventionist traditional dentist who holds sway, to the detriment of public health.

Rolling out the UN Sustainable Development Goals to all of these nations is a challenge in today’s strife-ridden world [http://www.un.org/sustainabledevelopment/sustainable-development-goals/]

 Major advances in dentistry in the past half century.

These are personal opinions. I believe them to be true advances, both in terms of their basic science and their application to healing and restoring people to oral and general health. Like all interventions they must be applied to the right patient, at the right time and in the right way. The fact that this is often not the case in practice does not mean that we should not regard the advances as real, and build on them appropriately.

  • Improved understanding of the pathogenesis of dental caries and of periodontal diseases, including microbiomics and metabolomics, and of the double-edged sword of the host response [Killian et al 2016].
  • Understanding the mode of action of fluorides in prevention of dental caries and appropriate application to individuals and communities.
  • Adhesive and tooth-coloured restorative materials
  • Development of osseo-integrated implants
  • CAD-CAM and 3D print technologies allowing accurate morphologic replacement of lost tissues
  • Improved understanding of the molecular pathogenesis of cancer and of auto-immune diseases, beginning the possibility of personalised treatments. Here we are only at the beginning and judgement of true value to populations and individuals remain unproven. [Ariywardana and Johnson 2017].
  • The growth of the discipline of health economics, improving rational and cost effective management of health systems for both prevention and treatment of disease. The introduction of cost-utility analyses to evaluation of health interventions in dentistry [Kularatna et al 2016].
  • Gradual incorporation of behavioural sciences into the education and practice of dentistry and oral health. [Schou, 2000; Tomar & Cohen, 2010]
  • Improvements in learning and teaching approaches, and greater opportunities for interprofessional education [Evans et al, 2015].

Observations on the process of dental caries [See Johnson, Editor, 1991a; Johnson and Beighton, 2016].

  • On a global scale we are not winning the war against dental caries. In spite of advanced economies such as those in Scandinavia having reduced the problem caries remains a major public health emergency in almost all low and middle income countries, and in certain groups in rich countries [Kassebaum et al 2015].
  • Oral biofilms are normal and natural. The health associated microflora must be retained. Broad spectrum antiseptics are to be discouraged because they damage the health-associated flora [Killian et al. 2016]. Their regular use is simply bad medicine.
  • Upstream and downstream risk factors all need to be managed, in the context of common risk factors. The profession in all countries must fully engage with governments and the whole of society to manage the social determinants of health. [Marmot & Bell, 2016].
  • In this multifactorial disease process, genetic and epigenetic predisposition and host defense factors are important, be they derived from saliva, blood stream, gingival crevicular fluid, or tooth substance [Fernando et al, 2017].
  • Excessive and frequent intakes of fermentable carbohydrates is the major environmental risk factor. The major contributor to dental disease worldwide is sucrose.
  • Top-down approaches [legislation] to restrict consumption of sugars will be effective, as with tobacco control. Apart from health education, governments have a role to play and new taxes on sweetened beverages [driven more by the global obesity epidemic] are to be welcomed. [eg UK Government. Op cit].
  • Enamel has great power to remineralise. Saliva is the best remineralising fluid in the world: at the pH of secretion it is supersaturated with Ca and PO4 ions; is at the right temperature; and it is free!!. A sniff of fluoride ions helps, so these have to be at the tooth surface. They can come from topical pharmaceuticals, toothpastes or from a fluoridated water supply..
  • Dentine has great power to lay down a defensive barrier. These responses must be recruited to aid treatment and tertiary prevention [Johnson et al 1969].

 

Observations on the periodontal diseases [See Johnson, Editor. 1991b]

  • On a global scale we are not winning the war against severe forms of periodontal diseases and tooth loss as a result. [Kassebaum et al 2014]. There are significant implications for general health as well as for oral health.
  • This is a family of diseases with variable/individual mix of host susceptibility and resistance factors. Patients must be treated as individuals. [Johnson, Griffiths et al 1998; Johnson, Huws et al. 2016].
  • These diseases are as much about the host defense mechanisms as about plaque and other local factors. A myopic approach to plaque control, and to scaling and polishing, is counterproductive.
  • Management of biofilm must seek to change the microbial ecology to a health-associated situation, not elimination of microorganisms. Widespread use of broad spectrum antiseptics is bad medicine and a bad public health message.
  • Modern molecular microbiology must [and is] being applied to understand what mix of organisms, and their overall metabolome, is pathogenic: how can this be modified to a health-associated flora? [Al-hebshi et al 2015].
  • Full screening of host general health and immune markers is key to diagnosis and treatment planning. Severe periodontal diseases are a medical problem.

Observations on head and neck malignancies

  • On a global scale we are not winning the war against oral cancer and other head and neck carcinomas.
  • The major risk factors are well understood. These are tobacco in all its forms, areca nut, excessive alcohol intake, poor diet, local environmental pollutants, genetic predisposition, infections with HPV and sometimes other viruses, and a disturbed oral mycobiome and bacteriome.
  • The approach to primary prevention is clear: use models of tobacco control to improve management of risk factors appropriate to specific populations, especially abuse of alcohol, smoked and smokeless tobacco, areca nut and sexual hygiene.
  • Recognise that these cancers are unique biological processes in unique hosts: diagnose, plan and treat accordingly. We are in the age of personalised medicine.
  • Oral health professionals must work with, and within wider teams of specialist care personnel. These include head and neck surgeons, radiologists, radiotherapists, medical oncologists, nurses, speech and language therapists, dieticians, physiotherapists, psychologists, experts in clinical trials, pathologists, molecular biologists, and others.

Observations on the clinical disciplines of oral medicine and oral/maxillofacial pathology [see Ariyawardana and Johnson, Editors, 2017]

  • The diagnosis and management of serious soft tissue disease in the mouth/head and neck, usually part of a systemic disease process, of dry mouth and of orofacial pain require special training. The specialty of oral medicine is quite strong in the UK and the USA, patchy elsewhere in Europe and weak in much of the rest of the world.
  • The pathology of the jaws, facial bones and odontogenic apparatus is a complex specialty. Oral pathology in much of the world is falling back into the hands of commercial general pathology labs. This is inimical to necessary research and the teaching of the oral health team.
  • Extensive education and training in dentistry plus general pathology [for oral pathology] and in dentistry plus general medicine [for oral medicine] have become necessary. If a practitioner wishes to combine oral pathology and oral medicine the training programme is unrealistic in time and expense.
  • These and other pressures risk seeing the demise of these specialties in much of the world. There are threats of takeover of non-tooth dentistry by general physicians in the USA and turf wars between medically-based otorhinolaryngologists for maxillofacial surgery go on and on. These considerations should be part of a fundamental restructuring of systems for promotion of oral health and of oral health care management, and education and training thereto.

Observations on “dental” research

  • We operate in silos. Whilst IADR is a great multidisciplinary organisation, this is mostly dentists talking to themselves. We must get out to basic science and parallel research groups and also work with, and present at, their meetings.
  • The dental research agenda is dangerously dominated by the dental industry. They are very supportive of our efforts, but there is no getting away from the fact that their bottom line is selling their products – to the public and the profession – at a profit for their shareholders. This means they cannot be ultimately interested in the elimination of disease.
  • We must recognize that dental treatment will not prevent the common oral diseases. We need better research and better approaches on upstream risk factors and on individual diagnosis and treatments.
  • The majority of dental caries and periodontal diseases can be managed by individuals practicing healthy life styles [particularly diet and hygiene] with support of a range of health professionals. It should not need expensively trained dentists on the current model.
  • In comparison to other organ-specific diseases [eg heart or kidney or lung], or disease processes [like cancer; chronic arthritis], or research disciplines [like microbiology] dental/oral research does not attract public interest. The profession should work with relevant experts to rebalance this.
  • In the categorisation of research areas, eg by Charities and Government funding bodies, “dental research” falls between the cracks. People in general are simply not interested. In reality dental research is behavioural science, epidemiology. statistics, embryology, anatomy, physiology, biochemistry, materials science, engineering, microbiology, molecular biology, economics…………..
  • When applying for public funds we must meet the standards of the relevant parent disciplines, and give our time to the service of funding bodies for equal recognition to evolve. There are striking examples of dental scientists rising to the highest level in national science matters [eg John Greenspan and HIV/AIDS – already mentioned; Ole Fejerskov and the Danish Research Academy; Mark Ferguson as Ireland’s Chief Scientist; Perry Bartlett and the Queensland Brain Institute] but they are few.

Observations on dental education

  • The traditional British/North American pattern of educating and training a profession separate from the rest of medicine is now self-evidently a failure.
  • This is deeply entrenched with powerful self-interest groups. These will be a major barrier to change.

Personal proposals on the way forward

  • “Put the mouth back in the body”. Integrate “dental” education with the rest of medicine and the behavioural and health sciences.
  • Create a large cadre of general health educators and promoters, with voluntary modules in oral health, probably at AQF Level 4. [AQF – the Australian Qualifications Framework – levels and the AQF levels criteria are an indication of the relative complexity and/or depth of achievement and the autonomy required to demonstrate that achievement. See: http://www.aqf.edu.au/aqf/in-detail/aqf-levels/]
  • Offer education and training after graduation and in-service experience, for a subset of these general health educators to have clinical training and be licensed as general nurses or dental surgery assistants, for example. Perhaps AQF Level 5 or 6: Diploma/advanced Diploma.
  • Provide undergraduate education in the “universals” of scientific method, basic biological and behavioural sciences, epidemiology and biostatics and grant first degrees in “biology and clinical methods”: perhaps called “clinical sciences”, probably after three years at university, equivalent to AQF level 7: Bachelor’s degree. Entry could be via the above steps or direct from secondary school with high grades.
  • Courses in different levels of community and healthcare work, eg. aged care, psychiatric nursing; orthodontic nursing, social work could lead to a Level 8 Graduate Certificate.
  • A further 2 years, to masters’ degree level, would allow qualifications as general dental practitioner, general medical practitioner, physiotherapist, nurse practitioner, midwife, pharmacist, optician etc. etc. equivalent to AQF level 9.
  • Specialisms based on scientific disciplines, and/or on human anatomy and organ-specific diseases, as third degrees. These would include, for example, oral and maxillofacial surgery, prosthodontics, periodontics, oral medicine and pathology, perhaps cariology, along with the traditional medical specialties such as paediatrics, cardiology, otolaryngology, ophthalmology etc etc. This is AQF level 10.
  • It is important that the numbers in training are related to clinical need in the country and particular community concerned, and not driven by fashion or predicted income or prestige. Workforce planning is an inexact science. The marketplace alone will not produce an optimal outcome, given the international transportability of such qualifications and the influences of war and international terrorism and mass movements of refugees and economic migrants. It is difficult to propose solutions to this aspect. Each country may have to approach the problems differently.
  • When it comes to delivery, design multidisciplinary teams comprising the best mix of special skills to serve the oral health heeds of a defined community.
  • These teams to be led by the best person available, irrespective of sub-specialty or training/professional label. The insistence that oral health teams be led by a dentist is counterproductive.
  • Test these models in a series of studies funded by governments and international philanthropic agencies across a range of different populations.
  • Immediately restrict the number of “traditional” dental schools in the world; Governments whose countries are oversupplied should legislate for closing the weakest and work towards merging others into comprehensive health sciences schools.
  • Research philosophy, methodologies and proper use of evidence-based clinical practice decisions would be a continuous stream.
  • Active research should be engaged in at all stages, including opportunities to take intercalated PhD degrees.
  • Encourage “time out” for other studies and for components to be taken in another, preferably overseas, institution. Respect the “other culture” [as discussed so elegantly by CP Snow. See https://www.britannica.com/biography/C-P-Snow
  • A major complexity to be dealt with in framing proposals for change will be the complexity of EU laws for equivalence and transportability of professional qualifications, and the UK attitude as part of Brexit negotiations. Other nations have other hierarchies. The Australian Qualifications Framework [AQF] levels and the AQF levels criteria are an indication of the relative complexity and/or depth of achievement and the autonomy required to demonstrate that achievement.

References

Al-hebshi NN, Al-Alimi A, Taiyeb-Ali T, Jaafar N. Quantitative analysis of classical and new putative periodontal pathogens in subgingival biofilm: a case-control study. J Periodontal Res. 2015 Jun;50(3):320-9. doi: 10.1111/jre.12210.PMID: 25040261

Al-hebshi N, Nasher A , Maryoud M, Homeida H, Chen T, Idris A, Johnson NW.  Inflammatory bacteriome featuring Fusobacterium nucleatum and Pseudomonas aeruginosa identified in association with oral squamous cell carcinoma. Submitted to Nature Scientific Reports, 281116, passed through triage and with referees, Mid December 2016

Allred H, Duckworth R, Johnson NW, Slack GL. Proposals for planned change in dental education and practice. 1972. Br Dent J. Sep;133 (5):173-9.

Amarasinghe HK, Johnson NW, Lalloo R , Kumaraarachchi M , Warnakulasuriya S.  Derivation and validation of a risk factor model for detection of oral potentially malignant disorders in populations with high prevalence. Br J Cancer. 2010 Jul 27;103(3):303-9.

Ariyawardana A, Johnson NW. (2013) Trends of Lip, Oral Cavity and Oropharyngeal cancers in Australia 1982-2008: overall good news but with rising rates in the oropharynx. BMC Cancer, 13:333. doi: 10.1186/1471-2407-13-333.

Ariyawardana A & Johnson NW Editors. Non-neoplastic Diseases and Disorders of the Oral Mucosa: Contemporary Challenges. Periodontology 2000, Special issue, In press November 2017

Baelum V, Fejerskov O, Manji F. (1991) The “natural history” of dental caries and periodontal diseases in developing countries: some consequences for health care planning. Tandlaegebladet. Mar;95(4):139-48. Review. PMID: 1948711

Baelum V, Chen X, Manji F, Luan WM, Fejerskov O. (1996) Profiles of destructive periodontal disease in different populations. J Periodontal Res. Jan;31(1):17-26. PMID: 8636871

Beighton D, Manji F, Baelum V, Fejerskov O, Johnson NW, Wilton JM.(1989)

Associations between salivary levels of Streptococcus mutans, Streptococcus sobrinus, lactobacilli, and caries experience in Kenyan adolescents. J Dent Res. 1989 Aug; 68(8):1242-6. PMID: 2632612

Cohen LK, Jago JD. Toward the formulation of sociodental indicators. Int J Health Serv. 1976; 6(4): 681-98.

Danielsen B, Wilton JM, Baelum V, Johnson NW, Fejerskov O Serum immunoglobulin G antibodies to Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Streptococcus sanguis during experimental gingivitis in young adults. Oral Microbiol Immunol. 1993 Jun;8(3):154-60. PMID: 8233568

Docking AR. Modern materials in dental practice. Aust Dent J. 1970 Aug;15(4):303-9.PMID: 4919880.

Evans AW, Johnson NW and Butcher RG (1983). A quantitative histochemical study of glucose-6-phosphate dehydrogenase activity in premaligant and malignant lesions of human oral mucosa. Histochemical Journal, 15:15:483-489.

Evans J, Henderson AJ, Sun J, Haugen H, Myhrer T, Maryan C, Ivanow KN, Cameron A, Johnson NW. The value of inter-professional education: a comparative study of dental technology students’ perceptions across four countries. Br Dent J. 2015 Apr 24;218(8):481-7. doi: 10.1038/sj.bdj.2015.296. PMID: 25908364

Farag A, Vaquette C, Hutmacher DW, Bartold PM, Ivanovski S. Fabrication and Characterization of Decellularized Periodontal Ligament Cell Sheet Constructs. Methods Mol Biol. 2017; 1537: 403-412.

Fejerskov O, Nyvad B, Kidd EAM. (2015) Dental Caries: The Disease and its Clinical Management. Wiley Blackwell 3rd edition.

Fejerskov O, Johnson NW, Silverstone LM. ]1974] The ultrastructure of fluorosed human dental enamel. Scand J Dent Res.;82(5):357-72. PMID: 4528817

Fernando S, Speicher DJ,  Bakr MM, Benton MC, Lea RA, Scuffham PA, Mihala G, Johnson NW.  Protocol for assessing maternal, environmental and epigenetic risk factors for dental caries in a population of Queensland children. BMC Oral Health. 2015 Dec 29;15(1):167. doi: 10.1186/s12903-015-0143-2.  PMID: 26715445

Gupta B, Kumar N, Johnson NW (2016) A risk factor-based model for upper aerodigestive tract cancers in India: predicting and validating the receiver operating characteristic curve. J Oral Pathol Med. Nov 7. doi: 10.1111/jop.12520. [Epub ahead of print] PMID: 27883362

Glick M, Monteiro da Silva O, Seeberger GK, Xu T, Pucca G, Williams DM, Kess S, Eiselé JL, Séverin T. FDI Vision 2020: shaping the future of oral health. Int Dent J. 2012 Dec;62(6):278-91. doi: 10.1111/idj.12009. PMID: 23252585

Glick M, Williams DM, Kleinman DV, Vujicic M, Watt RG, Weyant RJ. (2016). A new definition for oral health developed by the FDI World Dental Federation opens the door to a universal definition of oral health. J Am Dent Assoc. Dec; 147(12):915-917. doi: 10.1016/j.adaj.2016.10.001. PMID: 27886668

Harcourt JK, Johnson NW, Storey E. In vivo incorporation of tetracycline in the teeth of man. Arch Oral Biol. 1962 Jul-Aug; 7: 431-7.

Hobdell MH, Oliveira ER, Bautista R, Myburgh NG, Lalloo R, Narendran S, Johnson NW. (2003) Oral diseases and socio-economic status (SES). Br Dent J. Jan 25; 194(2):91-6;

Hobdell M, Petersen PE, Clarkson J, Johnson N. (2003) Global goals for oral health 2020. Int Dent J. Oct;53(5):285-8. PMID: 14560802

Hobdell M, Johnson NW, Lalloo R, Myburgh N. (2004) Progress in policy issues to improve oral health in Africa. Oral Dis. May;10(3):125-8. PMID: 15089920

James C. 1985 Falling Towards England: Unreliable Memoirs II. Jonathan Cape, London

Johnson NW (1963).  A method for assessing the reactions of the oral tissues of the rat to implant materials. British Dental Journal 116: 411-414.

Johnson NW. (1967) Some aspects of the ultrastructure of early human enamel caries seen with the electron microscope. Arch Oral Biol. 1967 Dec;12(12):1505-21. PMID: 5237335

Johnson NW (l973).  Implications for Dentistry of the recommendations of the Royal Commission on Medical Education and related questions.  British Dental Journal  135: 227-229.

Johnson NW (l976). The role of histopathology in diagnosis and prognosis of oral squamous cell carcinoma.  Proceedings of the Royal Society of Medicine 69:740-748.

Johnson NW. (1991a) Ed. Risk Markers for Oral Diseases, Volume 1. Dental Caries: Markers of High and Low Risk Groups and Individuals, Cambridge University Press.  pp507.

Johnson NW (1991b).  Ed.  Risk Markers for Oral Diseases, Volume II.  Oral Cancer. Detection of Patients and Lesions at Risk. pp393. Cambridge University Press.

Johnson NW. (1991c) Ed.  Risk Markers for Oral Diseases, Volume III. Periodontal Diseases: Markers of Disease Susceptibility and Activity. pp453. Cambridge University Press.

Johnson MW[NW], Taylor BR, Berman DS. (1969) The response of deciduous dentine to caries studied by correlated light and electron microscopy. Caries Res. 3(4):348-68. PMID: 5267932

Johnson NW, and Kenney EB (1972).  Effects of topical application of chlorhexidine on plaque and gingivitis in monkeys.  Journal of Periodontal Research 7: 180-188.

Johnson NW, Poole DF. Orientation of collagen fibres in rat dentine. (1967) Nature; 213 (5077): 695-6.

Johnson NW and Beighton, D. (2016) Dental Caries. Chapter 49 in Oral Diseases in the Tropics, pp 546-575. Revised reprint, Edited by Prabhu SR, Wilson, DW, Daftary DK and Johnson NW, Jaypee Publishers, New Delhi

Johnson NW, Griffiths GS, Wilton JM, Maiden MF, Curtis MA, Gillett IR, Wilson DT, Sterne JA. (1998). Detection of high-risk groups and individuals for periodontal diseases. Evidence for the existence of high-risk groups and individuals and approaches to their detection. J Clin Periodontol. 1988 May;15(5):276-82. Review. PMID: 3292592

Johnson NW, Gupta B, Ariyawardana A, Amarasinghe AAHK. (2016) Epidemiology of Oral Cancer and Site-Specific Risk Factors. Volume 1, Chapter 5. In Oral Cancer: a Comprehensive Approach. Principles | Prevention | Treatment | Rehabilitation. Editor In Chief: Moni Abraham Kuriakose, Roswell Park Cancer Institute, Buffalo, New York. Springer,

Johnson NW, Huws DA, Maiden MFJ, Griffiths GS. (2016) Inflammatory Periodontal Diseases. Chapter 51 in Oral Diseases in the Tropics, pp 591-626. Revised reprint, Edited by Prabhu SR, Wilson, DW, Daftary DK and Johnson NW, Jaypee Publishers, New Delhi

Kassebaum NJ, Bernabé E, Dahiya M, Bhandari B, Murray CJ, Marcenes W. (2014) Global burden of severe periodontitis in 1990-2010: a systematic review and meta-regression. J Dent Res. Nov;93(11):1045-53. doi: 10.1177/0022034514552491. Review. PMID: 25261053

Kassebaum NJ, Bernabé E, Dahiya M, Bhandari B, Murray CJ, Marcenes W (2015) Global burden of untreated caries: a systematic review and metaregression. J Dent Res. May;94(5):650-8. doi: 10.1177/0022034515573272. Review. PMID: 25740856

Kilian M, Chapple IL, Hannig M, Marsh PD, Meuric V, Pedersen AM, Tonetti MS, Wade WG, Zaura E. (2016) The oral microbiome – an update for oral healthcare professionals. Br Dent J. Nov 18;221(10):657-666. doi: 10.1038/sj.bdj.2016.865. PMID: 27857087

Kularatna S, Whitty JA, Johnson NW, Jayasinghe R, Scuffham PA.A comparison of health state utility values associated with oral potentially malignant disorders and oral cancer in Sri Lanka assessed using the EQ-5D-3 L and the EORTC-8D. Health Qual Life Outcomes. 2016 Jul 11;14:101. doi: 10.1186/s12955-016-0502-y. PMID: 27402015

Kumar S & Johnson NW. Oral health: Praying for preventive care. British Dental Journal 220, 322 – 323 (2016) Published online: 8 April 2016 | doi:10.1038/sj.bdj.2016.237, http://www.nature.com/bdj/journal/v220/n7/full/sj.bdj.2016.237.html

Kumar S, Kroon J, Lalloo R, Kulkarni S & Johnson NW. (2016) Association of obesity with dental caries in children varies across the categories of Socio-economic status. Int Dent J. Oct 17. doi: 10.1111/idj.12259. [Epub ahead of print]

Lalloo R, Kroon J, Tut O, Kularatna S, Jamieson LM, Wallace V, Boase R, Fernando S, Cadet-James Y, Paul A Scuffham PA and Johnson NW.  Study Protocol: Effectiveness, cost-effectiveness and cost-benefit of a single annual professional intervention for the prevention of childhood dental caries in a remote rural Indigenous community. BMC Oral Health, 2015, 15:99 DOI: 10.1186/s12903-015-0076-9, URL: http://www.biomedcentral.com/1472-6831/15/99

Marmot M, Bell R. (2016) Social inequalities in health: a proper concern of epidemiology. Ann Epidemiol. Apr;26(4):238-40. doi: 10.1016/j.annepidem.2016.02.003. PMID: 27084546

Mathu-Muju, K.R., Friedman, J.W. & Nash, D.A. (2016) Current Status of Adding Dental Therapists to the Oral Health Workforce in the United States. Curr Oral Health Rep 3: 147. doi:10.1007/s40496-016-0091-1

Naidoo S, Dimba E, Yengopal V, Folayan MO, Akpata ES. Strategies for Oral Health Research in Africa and the Middle Eastern Region. (2015) Adv Dent Res. Jul;27(1):43-9. doi: 10.1177/0022034515575539.

Nash DA, Friedman JW, Mathu-Muju KR, Robinson PG, Satur J, Moffat S, Kardos R, Lo EC, Wong AH, Jaafar N, van den Heuvel J, Phantumvanit P, Chu EO, Naidu R, Naidoo L, McKenzie I, Fernando E. (2014) A review of the global literature on dental therapists. Community Dent Oral Epidemiol. 42(1):1-10. doi: 10.1111/cdoe.12052.

Russell RRB and Johnson NW (l987).  The prospects of vaccination against dental caries.  British Dental Journal 162(1): 29-34

Schou L. (2000) The relevance of behavioural sciences in dental practice. Int Dent J.;Suppl Creating A Successful:324-32.

Sgan-Cohen HD, Evans RW, Whelton H, Villena RS, MacDougall M, Williams DM; IADR-GOHIRA Steering and Task Groups. Williams DM, Clarkson J, Cohen L, Fox C, Greenspan J, de Lima Navarro MF, Rekow ED, Pitts N, Jin LJ, Johnson N, Challacombe S, Mossey P, Sheiham A.(2013) IADR Global Oral Health Inequalities Research Agenda (IADR-GOHIRA(R)): a call to action. J Dent Res. Mar;92(3):209-11. doi: 10.1177/0022034512475214. Epub 2013 Jan 24.

Shaikh MH, Clarke DTW, NW Johnson NW, McMillan NAJ. Can gene editing and silencing technologies play a role in the treatment of head and neck cancer? Oral Oncology 68, 9-19

Sheiham A, Williams DM, Weyant RJ, Glick M, Naidoo S, Eiselé JL, Selikowitz HS. (2015) Billions with oral disease: A global health crisis–a call to action. J Am Dent Assoc. Dec;146(12):861-4. doi: 10.1016/j.adaj.2015.09.019. PMID: 26610819

Short L, Evans J, Mackay J, Johnson N(W), Nulty D, Evelyn E. (2010) Griffith University 2004. In: Tsang A, editor. Oral Health in Australia and New Zealand: Its Emergence and Development. Brisbane: Knowledge Books and Software.

Silverstone LM, Johnson NW, Hardie JM and Williams RAD (1985). Caries Dental: Etiologia, Patologia y Prevencion (Spanish Edition).  Manual Moderno, Mexico.

Squier CA, Johnson NW and Hopps RM. (1976).  Human Oral Mucosa. Development, structure and function. Blackwell Scientific Publications. pp129.

van Staden RC, Guan H, Johnson NW, Loo Y-C. (2017) Performance Evaluation of Bone–Implant System During Implantation Process: Dynamic Modelling and Analysis. Biomaterials for Implants and Scaffolds. pp 45-69, Springer, Berlin, Heidelberg

Storey E. (1975) Growth and remodeling of bone and bones. Role of genetics and function. Dent Clin North Am. 19 (3): 443-55.

Speicher DJ, Saravanan S, Kumarasamy N, Rangananthan K, Johnson NW. Comparison of plasma and salivary HIV loads determined via a coupling of the Abbott HIV detection system with the DNA Genotek OMNIgene™ DISCOVER (OM-505) kits

Proceedings of the International Symposium on HIV, Chennai, India, February 2014.  BMC Infectious Diseases 2014, 14(Suppl 3):P80  doi:10.1186/1471-2334-14-S3-P80.

Tomar SL, Cohen LK. (2010) Attributes of an ideal oral health care system. J Public Health Dent. 2010 Jun;70 Suppl 1:S6-14. doi: 10.1111/j.1752-7325.2010.00172.x.

Tuisuva,J, Smyth, JM., and Davies, G.N. (1995): A sequential modular curriculum for oral health personnel. Community Dental Health 12, 238-240.

Williams DM and Johnson NW (1976).  Alterations in peripheral blood leucocyte distribution in response to local inflammatory stimuli in the rat.  Journal of Pathology 118: 129-141.


  1. Participants in the creation of the La Cascada Declaration were requested to provide a summary of their career, with recognition of scientists who had mentored them and influenced their thinking. Such mentors are respectfully acknowledged throughout the present document.

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The Future of Oral Health Copyright © 2017 by Lois Cohen, Gunnar Dahlen, Alfonso Escobar, Ole Fejerskov, Newell Johnson and Firoze Manji is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.

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