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Proceedings of the International Conference on
Evidence Based Practice
in Dentistry
Kuwait, October 2–4, 2001
Faculty of Dentistry, Health Sciences Centre, Kuwait University
21 figures, 6 in color, 14 tables, 2003
Guest Editors
J.M. Behbehani,
Kuwait
E. Honkala,
Kuwait
Basel

Freiburg

Paris

London

New York

Bangalore

Bangkok

Singapore

Tokyo

Sydney


S. Karger
Medical and Scientific Publishers
Basel

Freiburg

Paris

London
New York

Bangalore

Bangkok
Singapore

Tokyo

Sydney
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Vol. 12, Suppl. 1, 2003
1 Preface
Behbehani, J.M.; Honkala, E.
3
An Evidence-Based Approach to the Prevention of Oral Diseases
Spencer, A.J.
12 Preventive (Evidence-Based) Approach to Quality General Dental Care
Elderton, R.J.
22
Tobacco and Oral Diseases. Update on the Evidence, with
Recommendations
Reibel, J.
33 The Evidence for Prosthodontic Treatment Planning for Older, Partially
Dentate Patients

Omar, R.
43
Stem Cells and Tissue Engineering: Prospects for Regenerating Tissues in
Dental Practice
Thesleff, I.; Tummers, M.
51 Dental Education in Kuwait
Behbehani, J.M.
56 Dental Education and Dentistry System in Iran
Pakshir, H.R.
61
Development of Oral Health in Africa
Thorpe, S.J.
65 Author Index
65 Subject Index
Contents
© 2003 S. Karger AG, Basel
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including tentative ones for forthcoming issues:
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www.karger.com/mpp_issues
Evidence Based Practice in Dentistry
Kuwait, October 2–4, 2001
Med Princ Pract 2003;12(suppl 1):1–2
DOI: 10.1159/000069848
Preface
ABC
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This supplement is based on papers presented at the
Second International Conference of the Faculty of Dentis-
try, Kuwait University, October 2–4, 2001. The confer-
ence provided an ideal opportunity to exchange ideas and
discuss new developments in the field of dentistry, espe-
cially the latest trends in the evidence-based approach to
dental care. As the former President of Kuwait Universi-
ty, Professor Faiza M. Al-Khorafi, stated in her opening
remarks, ‘In science, we need to question continuously,
what is the evidence? We look to science for answers, but
quite often science can only give us the best estimate for
probabilities. Our research results need continuous re-
evaluation, and the evidence must be weighed according
to the strengths and weaknesses of the scientific methods
applied.’
The evidence-based approach has been widely dis-
cussed in various healthcare fields and has influenced
teaching throughout the world. With its emphasis on pre-
vention and its use of previous, analogous evidence to
design treatment plans, the evidence-based approach dif-
fers fundamentally from traditional methods of interven-
tion, which focus on clinical outcomes. The stages of the
approach, including the synthesis and assessment of evi-
dence, the application of that evidence to a particular
case, and finally the monitoring and reassessment of the

intervention, are presented in detail in this supplement.
The preventive aspect of this approach is also addressed
in an article that re-evaluates traditional approaches to
the restoration of carious teeth, which give rise to the ‘re-
peat restoration cycle’ and in fact mask the underlying
disease process rather than prevent its occurrence. The
prevention of oral diseases caused by smoking is empha-
sized in a review of the documented harmful effects of
smoking on oral health; it is proposed that dentists should
make time during office visits to counsel patients on these
effects and guide them through smoking cessation pro-
grams.
As research in the field of dentistry develops and
expands and the evidence-based approach gains wide-
spread acceptance, traditional treatments are steadily giv-
ing way to new strategies of managing oral health issues. A
clear move away from tradition is discussed in an article
devoted to treatment planning for older, partially dentate
patients. It is proposed that the usual method of total
tooth replacement is not necessary, and the targeted
‘shortened dental arch’ is more effective and gives a high
level of patient satisfaction. Exciting new research on
stem cells and tissue regeneration indicate a distant but
hopeful possibility to grow new teeth to solve the ever-
present problems of dental caries and periodontal dis-
ease.
The second theme of the conference was ‘The Develop-
ment of Dental Education and Oral Health,’ with a
regional emphasis. The dental curricula of schools in two
Gulf countries, Kuwait and Iran, are presented in this

supplement, as is the issue of community health in Africa.
The dental curriculum at Kuwait University’s newly es-
tablished Faculty of Dentistry aims to promote oral health
in Kuwait through education, research and community
involvement. It incorporates recent trends in healthcare,
including the evidence-based approach which has become
an important component of comprehensive dental care
clinical work. In Iran, many new dental schools have been
established over the past 20 years, offering both under-
2
Med Princ Pract 2003;12(suppl 1):1–2
Preface
graduate and postgraduate training programs. The num-
ber of dentists and specialists in Iran is steadily increas-
ing, and just recently dental services have been incorpo-
rated into the public healthcare system. Efforts are also
underway in Africa to integrate oral health programs into
general health services, through the technical and finan-
cial support of WHO/AFRO. It is hoped that such pre-
ventive programs and new intervention strategies will
improve the level of oral health in many African coun-
tries.
As reflected in the presentations at this conference, the
vibrant research activity in the field of dentistry and the
efflorescence in dental education and oral health promo-
tion promise continued improvements in both dental
healthcare delivery and patients’ quality of life in the
coming years. It was an honor for the Faculty of Dentistry
at Kuwait University to host this conference and welcome
professionals and researchers from around the world, and

we look forward to another successful conference in De-
cember, 2003.
We would like to express the Conference Organising
Committee’s gratitude to Kuwait University for its con-
tinued support of our conferences, and the Advanced
Technology Company for the financial support of this
conference. We are also indebted to the Medical Princi-
ples and Practice Editor-in-Chief, Professor Farida Al-
Awadi, and Editor, Professor Azu Owunwanne, for their
help, strong support and commitment to publish this sup-
plement. Lastly, we would like to personally thank the
authors for their participation, contributions and cooper-
ation.
Dr. Jawad M. Behbehani Dr. Eino Honkala
Dean Chairman
Faculty of Dentistry Organizing Committee
Evidence Based Practice in Dentistry
Kuwait, October 2–4, 2001
Med Princ Pract 2003;12(suppl 1):3–11
DOI: 10.1159/000069846
An Evidence-Based Approach to the
Prevention of Oral Diseases
A.J. Spencer
Social and Preventive Dentistry, The University of Adelaide, Adelaide, S.A., Australia
Prof. A. John Spencer
Social and Preventive Dentistry
The University of Adelaide
Adelaide, SA 5005 (Australia)
Tel. +61 8 8303 5438, Fax +61 8 8303 4858, E-Mail
ABC

Fax + 41 61 306 12 34
E-Mail
www.karger.com
© 2003 S. Karger AG, Basel
1011–7571/03/0125–0003$19.50/0
Accessible online at:
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Key Words
Evidence-based
W Prevention W Oral diseases
Abstract
The evidence-based approach has become the mantra of
health care and service delivery. But just what it means,
whether it is feasible, how to build it and the outcome of
its use are not well understood. The aims of this paper
are to provide an overview of an evidence-based ap-
proach to the prevention of oral disease, to examine the
assessment of clinical trial evidence, to examine emerg-
ing approaches to assessing population-wide interven-
tions and oral health promotion, and to illustrate some
principles and issues through examples from preventive
dentistry. The evidence-based approach to prevention is
presented using an evidence loop, which emphasizes
that the evidence-base should begin with an understand-
ing to the burden of oral disease and its determinants,
rather than a consideration of the efficacy or effective-
ness of interventions in clinical dental research. A sys-
tematic review of evidence from clinical dental research
is compiled and assessed, after which the intervention is
decided upon and implemented. The evidence loop is

completed by the monitoring of outcomes and reassess-
ment of the intervention process. Attention is also given
to steps in assessing non-randomized population-wide
interventions and evidence on oral health promotion
based on expert opinion. The requirement for evidence
creates a substantial challenge which can only be met by
increased research activity, improved quality of informa-
tion and the appropriate application of the outcomes of
research to policy making for the prevention of oral dis-
ease.
Copyright © 2003 S. Karger AG, Basel
Introduction
The evidence-based approach has become the mantra
of health care and service delivery. It includes all aspects
of dentistry, not the least prevention. But just what it
means, whether it is feasible, how to conduct it and the
outcome of its use are not well understood. The evidence-
based approach to the prevention of oral disease relies on
knowledge of the effectiveness of identical, similar, or
analogous interventions usually carried out and evaluated
in a different setting at a different time. Toward the end of
the 1990s some journals published systematic reviews
and meta-analyses, or evidence-bases, using quantitative
scientific methods and consulting scholars around the
world about specific methods of appraising and quantify-
ing the benefits and risks of interventions. However, it
was found that outside a few areas of health care, clinical
trial evidence is scarce, particularly in many areas of den-
tistry. Many everyday decisions on health care, including
prevention of oral diseases, are based on public health

programs and policies founded on less scientific evidence
4
Med Princ Pract 2003;12(suppl 1):3–11
Spencer
Fig. 1.
An evidence loop for the prevention
of oral diseases.
than is required or desired. Not only is more evidence
needed, but new ways of examining population-wide
interventions and programs for oral health promotion are
also needed to assist decision-making.
A number of levels of evidence and methods to assess
them are being developed. New concepts for an evidence-
based approach and a range of old and new methods for
the assessment of evidence seem to be gaining greater clar-
ity. This paper provides an overview of the evidence-
based approach to prevention, and points out some of the
limitations to applying evidence to population-wide inter-
ventions and some issues in oral health promotion.
Evidence-Based Approach to Oral Disease
Prevention
The evidence-based approach to prevention begins
with the identification and definition of an oral health
problem for which an objective for oral health gain can be
stated. Related evidence on the efficacy of interventions is
synthesized and assessed, after which an intervention
plan is decided upon and implemented. Finally, the oral
health outcomes among patients or populations are moni-
tored and the whole process reassessed over time. These
fundamental components might be expanded into a more

detailed evidence loop for the prevention of oral diseases,
as presented in figure 1. Each aspect of this evidence loop
for the prevention of oral diseases is necessary for sound
decisions on either an individual or population level. Fol-
lowing the various stages ensures that resources are not
used to address less important problems or alter less sig-
nificant determinants, and that preventive interventions
are not maintained beyond their useful life should the
burden of disease alter. The loop also recognizes that
some interventions might work less satisfactorily in dif-
ferent contexts.
Burden of Oral Disease
In the evidence loop the problem is first identified,
defined and prioritized through information on the bur-
den of oral disease, which is the assessment of the magni-
tude and impact of oral health problems among patients
or populations. To design the appropriate intervention,
determinants of the disease are delineated and the level of
avoidable disease is assessed – i.e. how much of the dis-
ease is due to mutable risk factors and what proportion of
the burden of disease is avoidable.
Numerous ways exist to measure the burden of dis-
ease. Summary health measures such as Disability-Ad-
justed Life Years (DALYs) provide a common metric.
The DALY was first used in a comprehensive assess-
ment of the global burden of disease and injury in 1990
by the World Bank [1] and has been adopted by the
Evidence-Based Approach to Oral Disease
Prevention
Med Princ Pract 2003;12(suppl 1):3–11

5
World Health Organization to inform health planning [2].
DALYs provide a way to link the cause and occurrence of
a disease to both short- and long-term health outcomes,
including impairments, functional limitations (disability)
and death. One DALY is a lost year of ‘healthy’ life.
DALYs are a combination of years of life lost (YLL) due
to premature death and equivalent years of life lived with
disability (YLD).
Such population-wide ‘summary health measures’
have been emphasized recently in the development of
health policies. A report on the burden of disease and
injury in Australia [3] identified oral disease as one of the
top dozen major disease groups for non-fatal burden of
disease. While mental and nervous system disorders were
of substantially higher burden than any others, oral dis-
ease ranked in a group of diseases/disorders that are con-
sidered highly preventable, such as injuries and infectious
diseases. The oral diseases included were dental caries,
periodontal disease and subsequent edentulism. Years of
life lived with disability were predominantly linked to
dental caries (56.2%), then to periodontal disease (30.3%)
and finally to edentulism (13.5%). Young and middle-
aged adults experienced more years of life lived with dis-
ability from dental caries than did older adults, while
the years of life lived with disability from periodontal dis-
ease were distributed among middle-aged adult groups.
The main challenge of using summary health measures
is ensuring that the burden of disease is appropriately esti-
mated, so current estimates of the burden of oral disease in

DALYs require further consideration. Estimates of the
incidence of new disease from cross-sectional prevalence
data are not entirely reliable, because the assumptions
made in the translation of prevalence to incidence data do
not recognize the recurrence of the most common oral dis-
eases (dental caries and periodontal disease) at previously
affected sites. Furthermore, the estimates for the amount
of disability associated with each oral disease need scruti-
ny. The summary health measures cited above apply a sys-
tem of averaged levels of disability, handicap, mental well-
being, pain and cognitive impairment using a modified
version of the EuroQoL health status instrument; by these
measures, the disability weights for gingivitis and dental
caries were the lowest of all diseases or disorders [4], indi-
cating that the weights need further investigation.
Research using generic quality of life measures among
dental patients has shown a low level of impacts; however,
this type of research will help assess the relative weight-
ings ascribed to common oral diseases. Orally specific
measures of quality of life show a greater sensitivity for
oral impacts than do measures for general quality of life
[5], and they have been developed to identify those oral
diseases of greater burden that should be considered as
targets for prevention [6].
An evidence-based approach to prevention, therefore,
requires knowledge of the relative burden of disease asso-
ciated with particular oral diseases at different stages of
life and the proportion of that burden of disease that is
avoidable given associations with mutable determinants
of disease.

Determinants of Oral Disease
Preventive programs should be based on conceptual
and empirical evidence of the determinants of variation
in oral disease among patients or population groups in
order to identify more points of intervention in the pre-
vention of oral disease. The conceptual model illustrated
in figure 2 identifies three discrete yet closely interrelated
stages or levels of determinants: upstream, midstream,
and downstream [7].
Upstream level factors: The framework identifies so-
cial, physical, economic and environmental factors as
being the most fundamental determinants of oral health.
These include a range of interrelated factors such as edu-
cation, employment, occupation, working conditions, in-
come, housing, and area of residence. The framework also
indicates that these fundamental determinants are them-
selves influenced by even more upstream factors, namely,
government policies, globalisation, and culture.
Midstream level factors: Social, physical, economic
and environmental contexts throughout life influence
health either indirectly via psychosocial processes and
dental health behaviours, or more directly, for example
via injuries. The dental care system also plays some part
in determining oral health within a society. However, it
plays only a modest and moderating role.
Downstream level factors: Ultimately, oral diseases are
a consequence of adverse biological reactions to changes
or disruptions in various physiological systems. The
poorer health profile of some patients or population sub-
groups is due in part to longer-term adverse physiological

and biological changes that are brought about by poorer
psychosocial health and more harmful dental health be-
haviours.
The concept of ‘avoidable oral disease’ is based on an
understanding of these wider determinants for most oral
diseases and the evidence-base for the effectiveness of
possible interventions. Three issues at the centre of new
approaches to prevention are multifactorial causes of
chronic (including oral) disease, shared risk factors, and
life stages. It may be more effective and efficient to build
6
Med Princ Pract 2003;12(suppl 1):3–11
Spencer
Fig. 2.
Determinants of oral disease.
preventive efforts around common risk factors than to
develop separate preventive programs for each disease.
Activities to prevent many of the risk factors may be
undertaken in common settings, such as schools or health
centres.
Current knowledge suggests that oral health outcomes
are likely to be best when prevention is promoted
throughout life (beginning with the prenatal period and
infancy and extending through childhood, adolescence,
adulthood and older adulthood), because risks and pre-
ventive factors accumulate and interact over a lifetime in
a dynamic process. The principles, approaches and mes-
sages of health promotion (e.g. empowerment, equity,
health literacy, healthy behaviours, supportive environ-
ments) and specific preventive interventions are relevant

throughout a lifetime, but each life stage also has unique
contextual and behavioural aspects, and therefore partic-
ular strategies to reduce risk factors and strengthen pre-
vention are needed.
Integrated models are emerging that address the con-
tinuum of opportunities for prevention, such as the one
presented in figure 3, which was developed for Australia’s
chronic disease strategy [8]. In such models people are dis-
tributed across different target groups: the well popula-
tion, those at risk, those diagnosed with disease, and those
with controlled disease. Interventions are specific to these
stages and have different objectives, such as preventing
movement into the at-risk group, preventing progression
to established disease, or averting recurrence of disease
and loss of oral function. In such as approach to pre-
vention, the evidence-base on different interventions is a
key component of the support systems.
Synthesis of the Evidence-Base for Preventive
Interventions and Decision-Making
The evidence-based approach makes use of evaluative
research on the effects of an intervention to determine the
likely benefits or adverse consequences of intervention for
particular individuals or populations. When possible, evi-
dence of beneficial outcomes, rather than biological plau-
sibility or anticipated effects, is used [9]. Evidence of ben-
efits is derived predominantly from epidemiologic re-
search, which provides quantitative estimates of efficacy
or effectiveness. Summary estimates of effectiveness are
generated by a critical review of research data from two or
more studies using systematic review methods [10]. Sub-

group analyses may be used to identify characteristics of
people for whom an intervention is most or least effec-
tive.
The starting point for the traditional evidence-based
approach, therefore, is the searching for and collation of
the scientific evidence on a given intervention. Questions
concerning the intervention should be considered careful-
ly and in detail. Narrow rather than broad questions assist
the systematic review of evidence, but the question must
still be likely to support practical and potentially useful
interventions given favourable evidence.
Considerable emphasis is placed on the transparency
and reproducibility of the literature search. Finding stud-
ies relevant to an intervention is not easy; beyond sifting
Evidence-Based Approach to Oral Disease
Prevention
Med Princ Pract 2003;12(suppl 1):3–11
7
Fig. 3.
An integrated model for the opportunities for prevention of oral diseases.
through a mass of literature, there are problems of dupli-
cate publications and accessing the ‘grey literature’ such
as conference proceedings, reports, theses and unpub-
lished studies, as well as the new web-based literature
which is growing exponentially. As an initial step it is
helpful to find out if a systematic review has already been
done. If not, published original articles need to be found
through searches of databases using very explicit criteria
for inclusion/exclusion in the review. Bibliographies of
identified studies can lead to further relevant studies, and

hand searching and writing to experts are also essential.
The fate of all identified studies needs to be tracked,
whether included or excluded in the review.
Relevant studies are then summarized and the re-
search appraised. Numerous guides are available to assist
the process of abstracting information from selected stud-
ies and putting them in evidence table formats. Many
research publications, however, fail to include all the
information sought; this could be addressed by adhering
to a minimum set of information items that could reason-
ably be expected in research publications, such as those
suggested by the CONSORT statement [11].
Once the review is compiled, evidence is assessed to
determine the validity, reliability and precision of the
estimates of efficacy of the preventive intervention as well
as the size, importance and relevance of beneficial effects,
according to the following criteria:
E Strength of evidence: was the research good enough to
support a decision on whether or not to implement an
intervention?
E Size of the effect: what were the research results?
E Relevance: do they apply to the potential recipients of
the preventive intervention [12]?
The level of evidence indicates the validity of evalua-
tive research and takes into account the design of the
study, its potential for eliminating bias, and the methods
and analysis used [13]. An example of a classification of
the level of evidence based on study design is presented in
table 1.
As an illustration, we will apply the three above-men-

tioned assessment issues (strength of evidence, size of the
effect, and relevance) to the evidence-base for an oral
health preventive intervention: fissure sealants performed
in a clinic-based dental program for school children. Fis-
sure sealants have been the subject of much clinical trial
research. The level of evidence is high because the clinical
intervention can be randomly assigned to either children
or one of a contralateral pair of teeth, eliminating bias
and, with appropriate statistical testing, chance from out-
comes.
8
Med Princ Pract 2003;12(suppl 1):3–11
Spencer
Table 1.
Level of evidence and study design
Level of evidence Study design
I Evidence obtained from a systematic review
of all relevant randomized controlled trials
II Evidence obtained from at least one
properly designed randomized controlled
trial
III-1 Evidence obtained from well-designed
pseudo-randomized controlled trials
(alternate allocation method)
III-2 (observational) Evidence obtained from comparative
studies with concurrent or historical
control groups, cohort studies, case-
control studies or interrupted time-series
with a control group
III-3 (comparative) Evidence obtained from comparative

studies with historical control
IV Evidence obtained from case series
Excluded Evidence from expert opinion and
consensus of an expert committee
Source: [14].
The size of the effect has been expressed variously as
rates of retention of sealants over time or statistically sig-
nificant reductions in dental caries increment. Other
research has highlighted the intriguing potential for seal-
ants to prevent caries on adjacent non-sealed surfaces,
indicating that the effect may be larger than the pre-
vention of dental caries on sealed pit and fissure surfaces
[15]. However, there were more studies on the retention
of sealants than on caries increment, raising questions on
the appropriateness and relevance of outcomes. Reten-
tion is not the same as caries prevention [16].
In this example, it should be pointed out that different
studies may have used different measures of effect. Clear-
ly, only studies using the same measures are comparable.
It must be decided if studies using different measures will
be grouped together or if the type of effect measurement
will be a criterion for including the study in the evidence-
base or excluding it. Furthermore, the quality of individu-
al studies can vary even within a single level of evidence,
according to the study design; to address this potential
drawback, a quality score can be given to each study based
on methodological features like randomization, blinding,
and retention of subjects. Since this is a subjective judg-
ment, most systematic reviews are based on quality scores
given by two or more individuals. The level of agreement

among assessors needs to be reported.
After the research is appraised, the next stage is the
synthesis, or pooling, of the evidence. While this might
take a qualitative approach with some overview state-
ment, most often quantitative methods like meta-analysis
are used. Meta-analysis relies upon the similarity of stud-
ies and increases the power and generalizability of effects.
Analyses vary depending on the type of effect measure-
ment used (binary or continuous) and whether it is inde-
pendent or paired (as in many fissure sealant trials), as
well as on the sensitivity of the analysis and the potential
for publication bias. Sensitivity can be tested by analysing
studies that are rated at different levels of evidence sepa-
rately and comparing results. Another way to test sensitiv-
ity is to categorize by quality score those studies that fall
within a single level of evidence; this way, studies in dif-
ferent categories of quality score can be analyzed sepa-
rately, or studies in lower quality categories sequentially
added to the analysis and the results compared. A number
of discrete approaches exist to examining publication bias
including funnel plots and regression asymmetry.
Once the evidence is synthesized, decisions must be
made about how to apply the evidence, taking into consid-
eration the transferability of outcomes to patients or pop-
ulation groups and the predicted effects of implementing
the intervention. With regard to transferability, both the
beneficial and harmful effects of an intervention need to
be considered in the collective group of patients and dif-
ferent subgroups among those patients. Baseline risk of
disease must also be taken into account. To apply the evi-

dence to individuals, absolute benefits in target popula-
tions are predicted, and it is decided whether predicted
benefits outweigh any predicted harm.
While some guides to synthesis and decision-making
end here, the evidence-based approach to the prevention
of oral diseases includes a number of other important
issues, such as considerations of efficiency, public percep-
tions and side effects. Efficiency is determined by the rela-
tionship between the resources used and the outcome; it
includes economic analyses such as cost-effectiveness or
cost-benefit analyses. These techniques are also important
aspects of the evidence-base for prevention [17]. Percep-
tions of the public and side effects are covered briefly in
later sections.
Implementation, Monitoring and Reassessment
Once a decision on the appropriate oral health pre-
ventive intervention has been made, based either on a sys-
Evidence-Based Approach to Oral Disease
Prevention
Med Princ Pract 2003;12(suppl 1):3–11
9
tematic review of randomized clinical trials or an assess-
ment of observational studies, the intervention is imple-
mented. The last stage of the evidence loop is the monitor-
ing of patients or population groups and the reassessment
of the value and necessity of continuing the intervention.
While the importance of this final stage is readily ac-
knowledged, all too frequently resources and energy are
expended on the intervention and little effort goes into
monitoring the outcome. Without this reassessment at the

local level, questions on whether a program should contin-
ue or be modified will be inadequately addressed.
Limitations of the Rules of Evidence Applied to
Population-Wide Interventions
Recently, a number of limitations to the classic ap-
praisal and application of evidence for preventive inter-
ventions have come under scrutiny [18, 19]. Most public
health, population-wide preventive interventions are pro-
grammatic in nature, covering numbers of people in
defined areas. But studies are rarely conducted on such
interventions, and when they are, they are observational
studies and not randomized. Evidence derived from ob-
servational research is considered to be of a lower level
because of its potential for bias. However, this devalua-
tion of observational studies emphasises the issue of bias
and fails to recognize the importance of transferability.
Randomized clinical trials also have drawbacks because
they are conducted among unrepresentative samples of
the population. In addition, recruitment to a trial is often
associated with greater compliance with the intervention
than might be reasonably expected in the population,
leading to the distinction between a randomized clinical
trial and a community trial [20]. Furthermore, a random-
ized clinical trial takes place over a shorter period, possi-
bly masking either a decrease in efficacy over the longer
term or the emergence of side effects.
These difficulties with the accepted hierarchy of evi-
dence are illustrated by the issue of water fluoridation.
While cluster randomized controlled trials of water fluori-
dation could be designed in theory, studies of this type are

unknown. Instead, evidence on water fluoridation is gen-
erally derived from observational studies of discrete geo-
graphic areas with and without fluoridation, before and
after the water fluoridation was introduced. While these
designs may have been the most feasible, acceptable and
appropriate [21], they are considered to be at a lower level
in the evidence hierarchy [22]. The issue that emerges is
how to view a preventive measure where there is a large
number of studies which are all individually at a lower
level of evidence. A recent report argued that because of
the number of studies, the level of evidence should be
regarded as higher than that indicated by their study
design alone [23].
Another interesting evidence issue illustrated by the
case of water fluoridation is the public’s perception of the
intervention. An intervention will only be implemented if
there is general public support for its application. Despite
the successful implementation of water fluoridation pro-
grams in many countries, the public still does not know
much about it and expresses occasional concern about its
safety, while a sizeable minority of the population may be
undecided or opposed to it [24, 25]. Therefore, public per-
ception may assist or impede the implementation of an
evidenced-based preventive intervention, ultimately de-
termining whether the community will benefit from the
measure.
Evidence Issues in Oral Health Promotion
Health promotion programs which aim to improve
oral health often promote a mix of interventions, or a
‘portfolio’ [19]. These may be effective, but they do not fit

well the requirements for evidence of effectiveness. Also
important is the context or setting of interventions and
how it may shape the outcome.
For example, an oral health promotion program might
be built around existing ‘healthy’ baby activities such as
antenatal and parent education and well-baby and immu-
nization checks [26, 27]. There is an emerging interest in
this oral health promotion opportunity, but little research
has been conducted [28]. Interventions may be adopted
that are a combination of approaches that represent cur-
rent ‘best practice’ in health education, behavioural
change, avoidance of common risk factors, and monitor-
ing of health care providers. Recent reviews of health pro-
motion for oral health have evaluated such oral health
promotion interventions and adjusted the thresholds for
levels of evidence, specifically including expert opinion
and influential reports as a low but acceptable level of evi-
dence. They also weighed the revised levels of evidence
against the potential benefit for oral health [23]. The
potential benefit can be classified as one of the following:
E beneficial;
E likely to be beneficial;
E trade-off between beneficial and adverse effects;
E unknown;
E unlikely to be beneficial, and
E likely to be ineffective or harmful [23].
10
Med Princ Pract 2003;12(suppl 1):3–11
Spencer
A practical guide for decision-makers to use in select-

ing a portfolio or mix of interventions for oral health pro-
motion has recently been proposed as part of health pro-
motion planning and practice improvement [19]. Unlike
the approaches required for scientific, quantitative evi-
dence, such frameworks hope to ensure that the best avail-
able evidence, knowledge and expertise are brought to
bear on the problem at hand and that the portfolio ensures
a comprehensive approach to addressing the problem.
The distinct steps of the portfolio approach are:
E convene a decision-making group;
E specify the issue to be addressed;
E agree to the criteria against which to judge interven-
tions;
E weigh the criteria to be used to evaluate options;
E brainstorm a long-list of interventions likely to fulfil
the criteria;
E specify a short-list of interventions for more detailed
evaluation;
E evaluate the short-listed interventions against the
weighted criteria;
E score and prioritise the interventions;
E reflect on the outcomes of the exercise and refine if
necessary [19].
While such an approach uses the best evidence avail-
able, the disadvantages of these portfolios of interven-
tions are that they can never disentangle their component
effects, or might not be open to falsification.
Conclusion
Although the evidence-based approach is 30 years old,
just what it means, whether it is feasible, how to conduct it

and the outcome of its use are not well understood. This
situation holds in dentistry in general and in areas like
the prevention of oral disease in particular. In order to
present a comprehensive evidence-based approach to the
prevention of oral diseases, an evidence loop has been
presented. The evidence for the prevention of oral dis-
eases begins with an understanding of the burden of oral
disease at different life stages and the proportion which is
avoidable, given associations with mutable determinants
of disease. This provides a broad underpinning health
policy and priority setting giving direction to both indi-
vidual and population-wide preventive interventions.
The key questions to be addressed about those interven-
tions focus on the beneficiaries, efficacy, efficiency, public
perceptions and side effects.
A systematic review of the literature is a key compo-
nent of the evidence-based approach. Guidance is avail-
able for the searching, selecting, abstracting and apprais-
ing, synthesis and decision-making on clinical trial evi-
dence. While these guidelines are readily applicable to
clinical interventions, difficulties arise in the areas of pop-
ulation-wide interventions and oral health promotion, as
exemplified by the issue of water fluoridation where ran-
domization is not feasible, but lower level evidence is
available from community trials. Further difficulties arise
in the area of oral health promotion where portfolios of
interventions are common. More recently evidence-based
processes have emerged that are more appropriate for
these later situations.
Regardless of the level of evidence or approaches to its

appraisal, the evidence loop is completed by implementa-
tion, monitoring and reassessment. Too frequently an
intervention for which evidence has been found beneficial
is inadequately reassessed over time in target patients or
populations, but without reassessment it is difficult to
determine the value and necessity of maintaining a given
intervention. All of the stages of the evidence-based
approach are very important and taken together, they
offer a rational way forward to improve oral health and
dental care.
Acknowledgement
This paper is based on a presentation at the 7th World Congress
on Preventive Dentistry April 24–27, 2001, Beijing, China.
Evidence-Based Approach to Oral Disease
Prevention
Med Princ Pract 2003;12(suppl 1):3–11
11
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Evidence Based Practice in Dentistry
Kuwait, October 2–4, 2001
Med Princ Pract 2003;12(suppl 1):12–21
DOI: 10.1159/000069841
Preventive (Evidence-Based) Approach
to Quality General Dental Care
Richard J. Elderton
University of Bristol, Bristol, UK
Richard J. Elderton, BDS, LDS RCS (Eng), PHD (Lond)
Visiting Professor of Preventive and Restorative Dentistry
University of Bristol, 83 Bell Barn Road
Stoke Bishop Bristol BS9 2DF (UK)
Tel./Fax +44 117 968 6234, E-Mail
ABC
Fax + 41 61 306 12 34

E-Mail
www.karger.com
© 2003 S. Karger AG, Basel
1011–7571/03/0125–0012$19.50/0
Accessible online at:
www.karger.com/mpp
Key Words
Dental caries
W Dental practice W Dental treatment W
Evidence-based dentistry W Periodontal diseases W Repeat
dental restorations
W Repeat restoration cycle
Abstract
Restorative and scaling treatments have not generally
provided an effective method for managing dental caries
and periodontal diseases. Rather, restorative treatment
has often covered up the disease processes in the short
term and created a new problem: that of maintenance
and re-restoration of restored teeth. Thus, standard inva-
sive dental treatments that are commonly provided fail
to address the fundamental bacterial nature of the dis-
eases. Indeed, these treatments rather readily generate
and perpetuate a totally unacceptable chain of events.
This chain embraces many shortcomings, which them-
selves nurture what may be described as the repeat re-
storative cycle. The time has come to correct this iniqui-
ty. Dental caries and periodontal diseases are dynamic
conditions which need ‘managing’ with a focused cock-
tail of preventive and refined restoration care. Much
more emphasis should be placed upon the assessment

of each and every caries or periodontal lesion, with a
view to implementing specific preventive measures and
allowing the natural arrest of disease processes to occur.
The universal adoption of a preventive (evidence-based)
approach to making dental treatment decisions could be
by far the most powerful factor in reducing the restora-
tive burden of dental services. It is clear that dental edu-
cation and practice need to rise proactively to the chal-
lenge, or changes will be forced upon them while they
are in a defensive position. There is a need to move
wholeheartedly and contentedly into the preventive era.
Copyright © 2003 S. Karger AG, Basel
Introduction
Traditional restorative dentistry has had a strong in-
fluence on dental education and practice in many parts of
the world, and invasive restorative treatment has tended
to take precedence over non-invasive preventive mea-
sures. It appears that many dentists erroneously presume
that dental caries can be ‘treated away’ with restorations
and that periodontal diseases can also be ‘treated away’ by
regular scalings. Indeed, many dentists seem to believe
that traditional dental treatment automatically results in
oral health [1].
Dental caries and periodontal diseases, both bacterial
in nature, are largely preventable from the start. But they
are not always prevented; rather, the forces leading to the
diseases are allowed to remain out of balance with those
that lead to health. The situation prevails today whereby
the scientific basis of these diseases has largely been estab-
lished [2, 3], but the services providing appropriate dental

care to manage them remain out of date and fail to be
properly evidence-based.
Thus, much of the profession appears still to be wed-
ded to the traditional invasive ‘treatment’ that fails to
address the causes of the diseases. When the diseases
occur, there is a need for a real and responsible commit-
ment by the dentist to help the patient revert to a disease-
Quality General Dental Care
Med Princ Pract 2003;12(suppl 1):12–21
13
free status by restoring the balance so that the forces tend-
ing to prevent the diseases outweigh the forces contribut-
ing to their progression.
Caries
Caries is not simply a one-way process. All carious
lesions involve both demineralisation and remineralisa-
tion phases [4]. A lesion increases in size only when the
calcium and phosphate ion exchange between the tooth
and the saliva, mediated by bacterial plaque, favours net
mineral loss over long time periods. Such lesions may be
described as active. On the other hand, if and when the
conditions are such that the calcium and phosphate ion
exchange favours mineral gain over time, the lesion may
be described as arrested. Causing carious lesions to arrest
should be a primary preoccupation of dentists.
Caries is very much related to environmental and life-
style habits such as bacterial plaque, dietary patterns, and
fluoride usage, which are themselves very much linked to
things like living conditions, economic factors, education
levels, school routines, work routines, home and leisure

routines, social habits, and personal whims and fancies.
Consider the patient who has an active class II carious
lesion that has extended well into the dentine. Most clini-
cians would agree that when this stage of caries develop-
ment has been reached, it is necessary to excise the dis-
eased tissue and make good the defect with a restoration
[5]. But that is just one phase. It is also necessary to bring
about a change in the environment of the tooth and of the
rest of the dentition so as to prevent further caries, includ-
ing the development of new primary carious lesions [6].
Thus, proper caries management is all about identifying
the main aetiological factors, and selecting and targeting
specific efficacious preventive measures to help overcome
specific imbalances. It is also about causing patients to
make relevant adjustments, in a highly focused manner,
to their dietary patterns, oral hygiene habits and fluoride
(and chlorhexidine, xylitol, etc.) usage as appropriate. Fis-
sure sealants may also be necessary. The whole process
will need monitoring and perhaps fine-tuning over time
[7].
So, in addressing the question ‘How should the profes-
sion be managing caries?’ the answer has to be by estab-
lishing regimens with patients, such that the diseases are
arrested and prevented from recurring through environ-
mental and lifestyle measures (though backed up by pro-
cedures to restore form and function where appropriate).
It is essential that the regimens advised are tailored to the
individual, and that they are sympathetic to the individu-
al’s environmental and lifestyle characteristics.
Caries prevention works, so once a preventive philoso-

phy prevails, then the whole attitude to invasive proce-
dures changes. Many carious lesions that would have been
restored under the traditional model of dental treatment
can be made to arrest, and many existing but morphologi-
cally deteriorated restorations can be allowed to continue
to function satisfactorily [8].
Thus, modern quality dentistry requires the dentist to
have the wisdom and courage to ‘go modern’ with restora-
tive treatment decision making – substituting preventive
care for some invasive procedures. Where restorations are
required, they will necessarily be minimally invasive and
of high technical quality [9]. Thus the routine use of rub-
ber dam, magnification, sharp hand instruments, well-
adapted contoured matrix bands, all used with finesse at
every stage, becomes integral with modern prevention-
based restorative dentistry.
Periodontal Diseases
Plaque-induced periodontitis is believed to involve
periods dominated by tissue destruction and periods
dominated by tissue repair [10]. Between these fluctua-
tions of activity there appear to be periods of quiescence
and stability. Net loss of epithelial attachment and alveo-
lar bone destruction occur when the interactions between
the bacteria and the patient’s responses are out of equilib-
rium such that they favour pathological destruction and
loss of structure [11].
Consider the patient who has gingivitis and destructive
periodontitis, in whom plaque-induced inflammation has
led to apical migration of the gingival epithelial attach-
ment to the root surface of the tooth. The aim of treat-

ment is to arrest attachment loss and cause a reduction in
pocket depth; indeed, the aim is normal-looking gingival
tissue with pocketing no greater than about 4 mm which
does not bleed or discharge pus on probing. The treatment
should take the form of effective daily oral hygiene carried
out by the patient, plus professional scaling and removal
of noxious elements in the periodontal pockets, including
the removal of the complex subgingival mass of bacteria
which may be adhering to the root surfaces. Other treat-
ment, such as the reshaping of restorations, may also be
necessary. As with caries, the prevention phase is critical.
However, whatever the patient does, plaque may return to
the deeper parts of the gingival crevice, so ongoing profes-
sional care may be needed at specific sites.
14
Med Princ Pract 2003;12(suppl 1):12–21
Elderton
It is necessary to ask, and where necessary address in
depth, some questions regarding the treatment and pre-
vention of destructive periodontal disease. For example:
(a) How well does the patient remove visible plaque on
an ongoing basis?
(b) Is the patient still using the non-favoured ‘roll’ tech-
nique of brushing as opposed to a method involving clean-
ing of the gingival crevice?
(c) Has the dentist or hygienist effectively taught the
patient a realistic method of plaque control, tailored to his
or her individual needs?
(d) Has the dentist unwittingly implied that multiple
daily toothbrushings are desirable or indeed a panacea for

oral health (which they are not)? Certainly, such multiple
daily toothbrushings are irrational with respect to caries
as well as periodontal diseases, for it is well known that
disease-causing plaque takes longer than 24 h to become
established.
(e) Has flossing advice been sufficient?
(f) Is the patient or the professional incorrectly assum-
ing that antibacterial mouthwashes used in the long term
are able to make up for deficiencies in mechanical plaque
control and that they can therefore be relied upon to pre-
vent further disease [12]?
(g) And, worst of all, is the dentist living under the illu-
sion that a ‘quick scale and polish’ from time to time itself
constitutes appropriate care/treatment? Often it does not.
It is easy to fail with preventive care and treatment
against periodontitis, on the false basis that it can be
accomplished by means of a regular ‘scale and polish’,
along with a few minutes of instruction about oral hygiene
and some general advice given every now and again. Sev-
eral experts have indicated that proper subgingival scaling
and root planing take some 5–7 min per tooth [13], or
more [14]. Further, ineffective scaling and polishing may
actually do more harm than good, in that while failing to
achieve its objective, it may cause damage to the attach-
ment and to the hard dental tissues, even to the extent of
taking away some of the high-fluoride outer zones of the
teeth [15].
By far the most important thing to do is to inform the
patient that it is his or her success with daily plaque con-
trol that is the vital factor in determining the long-term

outcome. And if the patient is a tobacco smoker, then
attempting to convince him or her to quit the habit should
be seen as an important component of the preventive den-
tal package, since smoking has a markedly adverse effect
upon periodontal inflammation and healing [16].
Dental professionals should appreciate that giving pre-
ventive advice in the form of oral hygiene instruction is
not of itself a preventive measure. The preventive mea-
sure succeeds when the patient actually achieves excellent
daily oral hygiene; it is this latter which must be the objec-
tive.
Why the Problem?
Why does evidence-based quality general dental care
constitute a challenge to the profession? Surely it should
naturally form the basis of all dentistry, shouldn’t it? After
all, dentists are professionals, and professionals should,
by definition, avow to offer the best for their patients. The
old adage ‘Prevention is better than cure’ is well known,
but if dental diseases do occur, it is important to treat
them as non-invasively as possible. Ask the World Health
Organization or any health minister whether or not it is
better to have diseases such as polio, yellow fever, cholera
or AIDS in a community or to prevent their occurrence.
The answer does not need stating, so why do large seg-
ments of the dental profession appear to ‘accept’, as if it
were inevitable, the occurrence of avoidable dental dis-
eases such as dental caries and periodontal diseases?
What has contributed enormously to the present pro-
file of traditional dentistry, including the teaching in den-
tal schools, has been the widespread dissemination of

G.V. Black’s principles of cavity preparation in the early
part of the last century, followed by a phenomenal growth
in operative dentistry over the years, particularly up to
about 1975. The world saw a proliferation of dental
schools with vast areas of clinical space devoted to opera-
tive dentistry. The clinics became powerhouses, dominat-
ing all other activities and engulfing large portions of cur-
ricula. Hume [17] has described the phenomenon as a re-
storative tiger that needs ‘taming and turning’. If G.V.
Black, who has been described as the Father of Dentistry,
were alive today, he would have been at the forefront of
the taming and turning process [18].
A problem here lies in the fact that it is rather easy for
both patients and dentists alike to naively believe that
operative dental treatment automatically results in oral
health. And many dentists have little experience of dis-
ease control (as distinct from providing operative treat-
ment), even though they should, theoretically at least,
have retained the necessary knowledge from their under-
graduate training days. However, the stark facts of the
matter are that patients in a low-risk category for caries
can inadvertently be shifted towards a significant risk of
ongoing replacement restorations once the first set of res-
torations has been placed in the teeth [19].
Quality General Dental Care
Med Princ Pract 2003;12(suppl 1):12–21
15
To illustrate this point, it is relevant to consider a pro-
spective study of dental treatment provided to a large ran-
dom sample of dentate adults in Scotland. It showed that

the amount of operative treatment the patients received
over a 5-year period related very much to their dental
office attendance patterns and to the number of teeth
which already contained restorations [20]. Indeed, it was
found that the average number of tooth surfaces restored
during any one course of treatment was approximately the
same on average, regardless of the frequency of the
courses. Thus the patients who went to the dentist more
frequently received more restorations per unit of time (al-
most in direct proportion to the number of courses of
treatment received). Further, the proportion of restora-
tions that were replacements increased markedly as the
total number of restorations present increased.
Somewhat inevitably, therefore, it was found that the
more restorations a patient had, the more the patient was
likely to receive. And the people who received the most
restorations tended to be relatively well educated and con-
ditioned to visiting their dentists regularly. Overall, it was
found that 50% of restorations were placed in the teeth of
just 12% of the population. This 12% therefore represents
a group at high risk of receiving yet more restorations;
after all, they had their restorations examined more fre-
quently than those who attended more rarely, so the
chances of a morphologically defective restoration being
targeted for replacement were greater in these individuals.
Certainly it cannot be assumed that dentistry, as widely
practised, is necessarily good for the teeth. The corre-
sponding figures for other countries may differ somewhat
from those given above, but it is likely that equivalent
scenarios are found elsewhere.

Table 1.
The potential chain of events which leads to many shortcomings of traditional restorative dental treatment and nurtures the repeat
restoration cycle
The patient visits the dentist but
Clinical examination procedures are often rather simplistic and casual
and
Diagnostic tests (for caries and other lesions) are largely subjective [21–23],
so it is not surprising that
Caries diagnoses are often inaccurate [23–25].
y
At the same time
Caries status is not properly taken into account
and
Caries risk factors are not generally considered [26].
y
Even in doubtful situations
Undertaking restorations is considered to amount to ‘good dentistry’ [27],
so it comes as little surprise that
Restorative decisions tend to be idiosyncratic and somewhat aggressive [27–29].
y
Thus
Caries aetiologic factors are not modified
and
Preventive backup is inadequate [8],
i.e.
Caries is not managed as a disease [6, 8].
y
Indeed
Dentists appear to gain fulfilment by cutting away sound tooth substance (such cutting being a primary function of the high-speed drill).
Thus

The use of outdated concepts of cavity design (perpetuating Black-type cavities involving excessive cutting of sound tooth substance)
is commonplace [30, 31]
and
Dentists fail to appreciate the exacting nature of restorative procedures.
y
16
Med Princ Pract 2003;12(suppl 1):12–21
Elderton
Table 1
(continued)
It is no surprise therefore that
Restorations of mediocre quality are readily placed [30, 31].
Sadly
These restorations often contain characteristics consistent with inbuilt obsolescence.
In addition
Bur damage, for example, is imparted commonly to the adjacent tooth [32]
and
Non-physiological approximal contours frequently lead to plaque accumulation and periodontal disease.
y
In due course the patient is recalled but
Recall assessments of restorations tend to be idiosyncratic [33].
Thus, for example,
Ditched margins are commonly assumed to signal failure of the restoration [5, 30]
and
Existing restorations are readily deemed to have failed [20, 34], particularly if the patient has just changed from a previous dentist [35].
However
The matter of why restorations have failed is not questioned by the dentist or patient.
y
Nevertheless
Restorations are readily cut out and replaced

in spite of
The causes of failure often not being identified correctly [36].
y
It is almost ubiquitous that
The cavities increase in size when restorations are replaced [30, 37]
and consequently that
The teeth become weaker [39].
y
It is no surprise to find that
Errors in the previous restorations are often repeated in the new ones [30]
so that
The inbuilt obsolescence in the restorations is perpetuated.
y
Inevitably, as they increase in size
The restorations become more complex and difficult to carry out [38, 39]
and
Correct chemical treatment of the cavity, where necessary, becomes less certain.
Further, one cannot escape the fact that
Bacteriological, mechanical and chemical insult to the pulp is increasingly likely to occur.
y
Overall
The dentist fails to realise the iatrogenic nature of the ‘treatment’.
Indeed
The dentist genuinely believes he/she is making the patient more healthy.
At the same time
The patient is under the illusion that he/she is actually being made more healthy.
y
But deterioration continues such that, for example,
Gross fracture of the tooth may occur
and

Crowning may be effected as a ‘cure-all’ procedure.
However
The crown fails to properly fit the margins of the prepared tooth
and, if visible,
The crown looks artificial.
y
Quality General Dental Care
Med Princ Pract 2003;12(suppl 1):12–21
17
Table 1
(continued)
Inevitably
Plaque stagnation, halitosis and periodontal disease (and perhaps caries also) increase.
y
In due course
The need or perceived need for endodontic treatment arises.
y
However
Root canal preparation is often inadequate
and
Root canal obturation is often incomplete, leaving a nidus for continuing bacterial proliferation.
y
Not surprisingly
Periapical seepage of bacterial toxins occurs
so
The periapical lesion persists.
y
This may lead to
Apicectomy and retrograde root filling taking place, though without first making the root canal filling adequate.
y

Surprisingly, with this invasive procedure
The dentist now feels he/she really is saving the patient’s dentition.
y
But
The tooth fails to settle and symptoms continue
so
Repeat compromised endodontic or apicectomy treatment takes place
and inevitably
Pain and sepsis remain ongoing.
y
At some stage
A post is liable to be placed, further weakening the tooth.
y
Patronisingly
The dentist blames the patient for having a weak tooth with unfavourable root canal morphology
so
The tooth is extracted.
y
Nevertheless
The dentist feels overall that he/she has done a good job in providing ‘quality’ care over the years.
y
To overcome the missing tooth
A bridge is placed
but unfortunately
The occlusion and aesthetics are altered unfavourably and the patient is dissatisfied.
y
In due course
The bridge gets replaced
but
There is minimal accompanying anticaries or antiperiodontal disease advice.

y
Next
An abutment tooth fails and is extracted
so
A larger bridge is made involving more teeth.
y
18
Med Princ Pract 2003;12(suppl 1):12–21
Elderton
Table 1
(continued)
Because the bridge morphology is compromised
Plaque accumulates and periodontal disease increases.
y
Indeed, from the very beginning, the following almost ubiquitous and vain scaling scenario is likely:
Each scaling results in clean teeth for a day
but
Bacterial plaque then returns, engendering further periodontal disease.
However
The periodontal disease is not properly evaluated or documented.
Indeed
The periodontal disease is not prevented or treated.
Instead
Further scaling takes place, leading to clean teeth for another day.
But inevitably
Bacterial plaque returns to continue the disease process
and
Irreversible alveolar bone loss is liable to take place as periodontitis takes a hold.
At the same time
Halitosis becomes a real issue for the patient

but
The halitosis is not even considered by the dentist.
Over the years
The scaling cycle is repeated many times in the absence of proper periodontal care/treatment
so
The periodontal disease carries on, largely unabated.
y
Not surprisingly
Further tooth loss occurs.
y
In an attempt to restore appearance
A removable partial denture is made.
y
But somewhat inevitably
The periodontal disease continues to spread.
y
Whether privately or through third-party funding
Costs continue to spiral as the dentition deteriorates.
y
Looking at the wider scene, it is clear that
Dentists fail to appreciate that the public is not very satisfied.
Indeed
Dentists tend to forget that patients do not like having restorative treatment [40, 41].
y
Thus
The public is unhappy about dental services [42]
and
The dentist feels dissatisfied also [43].
Indeed
The dentist becomes increasingly disillusioned with dental practice

and
He/she loses any zest for quality care.
Sadly
Burn-out rather readily sets in and the dentist spirals downwards [43].
y
This inevitably means that
Any hope of quality dental care is gone forever.
Quality General Dental Care
Med Princ Pract 2003;12(suppl 1):12–21
19
The Repeat Restoration Cycle
Research over the last 20 years or so has made it possi-
ble to assemble a model of the potential chain of events
that embraces many shortcomings of traditional restora-
tive treatment, namely the repeat restoration cycle. This
potential chain of events is given in table 1. The contents
of this table form an integral part of the text of this paper
and should be read at this stage.
The repeat restoration cycle is driven by a culture of
drill-related dentistry. Thus, many dentists have an urge
to place and replace restorations, apparently feeling ‘com-
fortable’ when they intervene invasively [8, 20, 42]. Fur-
ther, there is an apparent disregard for the inevitable
weakening of the teeth in the process, especially as the res-
torations are placed and replaced over the years. After all,
by virtue of the repeat restoration cycle, it is inescapable
that restorations are often not very durable (many surviv-
ing only for a few years) [44–49]. And, of course, restora-
tions do not cure caries anyway.
The characteristics of the repeat restoration cycle are

totally unsatisfactory in an age of potential evidence-
based dentistry and at a time of increasing accountability.
Yet there is a strong implicit message to patients that any
operative treatment suggested is both necessary and
worthwhile. It is well known that most ‘treatment’ under-
taken in dental practice is not at variance with what was
taught in dental school. But the dental school was yester-
day. Today’s patients require today’s care.
In light of the repeat restoration cycle, is it really sur-
prising that the profession suffers from low morale and
stagnant motivation, when mechanistic solutions to bio-
logical problems weigh so heavily in many dental prac-
tices?
Patients often do not understand what is going on –
they do not understand the repeat restoration cycle – and
as ‘consumers’ they have varying levels of faith, ranging
from suspicion and distrust to acceptance of virtually any-
thing the dentist suggests.
Moving Forward towards Evidence-Based
Dental Care
It is essential that the dental profession breaks away
from yesterday’s concepts in favour of dental care aimed
at optimising oral health and maintaining the natural den-
tition in as intact a state as possible. Some members of the
profession have made this break already and are provid-
ing excellent evidence-based quality dental care. In addi-
tion, they report a marked improvement in the quality of
their working lives as a result. Sadly, it has to be noted
that many dental school teachers have very definitely not
made the break. It is clear that considerable changes are

required in dental education [50].
By referring to restorations as ‘treatment’, the profes-
sion has drifted hopelessly away from evidence-based
dentistry [6]. Yet the profession is steeped in the use of the
term when often no treatment is in fact provided, just res-
torations that readily lock the patient into the repeat res-
toration cycle, each restoration being less prophylactic
and more iatrogenic than the one before. Thus, to the
patient who asks ‘Do I need any treatment?’ it is a very
naive dentist who replies, ‘Yes, two fillings.’ A more
appropriate reply might begin along the lines of, ‘Yes, you
have two carious lesions, so we need to set about altering
the nature of the chemical processes going on in your
mouth in order to cause the lesions to arrest ’
With the public’s increasing awareness of the short-
comings of traditional restorative dentistry and, at the
same time, a heightened understanding of the possibilities
for prevention, patients can be expected more and more
to demand preventive ‘quality’ dental care. Indeed, it
seems that the supply-and-demand forces of the market-
place will reinforce the scientific argument and put in-
creasing pressure upon dentists to adopt a more pre-
ventive approach to the management of caries, defective
restorations and periodontal diseases. Then the patient
who attends regularly will become less ready to accept an
apparently unending commitment to restorations and
re-restorations, with scales and polishes thrown in from
time to time.
As caring professionals, dentists should stop pretend-
ing that operative treatment is necessarily rational. Pre-

vention and the promotion of health are becoming in-
creasingly necessary in order to satisfy the requirements
of today’s people, undertaken within a context of evi-
dence-based oral health care. The real challenges for the
future are: (1) for dental education to accept whole-
heartedly the changes mentioned in this paper, and to ‘run
with them’; (2) for dental practice to put the changes into
action out in the field, and (3) for licensing bodies and
remuneration systems to develop in sympathy.
Thus, there is a fundamental need for a reappraisal of
dental education. But questions remain as to how univer-
sity teaching staffs can be brought fully up to date so as to
assist the change in emphasis towards prevention and
thereby help tame Hume’s [17] restorative tiger [18]. Ini-
tiative and innovation are now required in order to bring
about the necessary changes in dental education to suit it
20
Med Princ Pract 2003;12(suppl 1):12–21
Elderton
to the needs of the changing world. There is a clear need
for all those involved in providing oral health care, espe-
cially licensing bodies and those responsible for health
care delivery, to widen their perceptions of the issues at
stake and thereby enable forward-looking curriculum de-
velopment. Either the profession stands up and says what
good dentistry is, or the public and politicians will force
their way, and the profession will then be in a defensive
position and less ready to respond in an acceptable man-
ner.
Conclusions

Standard, invasive dental treatments such as restora-
tions and scaling are in general not an effective way to
manage dental caries and periodontal diseases. Much
more emphasis should be placed upon the assessment of
each and every carious and periodontal lesion with a view
to allowing a possible natural arrest of the processes to
occur, aided by specific preventive measures as appro-
priate. Existing restorations should not necessarily be
replaced just because there is a moderate degree of mar-
ginal breakdown. In view of the adverse potential of the
repeat restoration cycle, the withholding of restorative
treatment when appropriate may itself be considered a
prime preventive measure. Indeed, the universal adop-
tion of a preventive, evidence-based approach to treat-
ment decisions could be by far the most powerful factor in
reducing the restorative burden of dental practice.
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