evidence based periodontics

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EVIDENCE BASED PERIODONTICS
Contents
• Introduction.
• Need for Evidence Based Decision Making.
• Advantages of Evidence Based Approach.
• Process of Evidence Based Decision Making.
• Sources of Evidence.
• Appraising the Evidence, Evaluating the Outcomes, Assessing Evidence.
• Contradictory studies.
• Implementing Evidence Based Decisions in Clinical Practice.
• Change management
• References.
Introduction
Evidence based medicine was pioneered at Mc Master University, Ontario, Canada in 1980s.
It was defiend by Sackett et. al. In 2000 as “the integration of the best research evidence with
clinical expertise and patient values”
It has 3 new aspects:
 Evidence obtained from randomised controlled trials.
 Systematic review and meta-analysis to synthesise and analyse the evidence.
 Electronic databases to access the evidence.
Evidence based dentistry has been defined by ADA in 2002 as “an approach to oral health
care that requires judicious integration of systematic assessment of clinically relevant
scientific evidence relating to the patients’ oral and medical conditions and history, with the
dentist’s clinical expertise and the patient’s treatment needs and preferences.”

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Needfor Evidence BasedDecision Making
Variations in Practice
Clinicians tend to practice the same as they were taught in dental schools. Thus, the longer
they have been out of school, the greater the gap in their knowledge of up-to-date care.
Variations also occur because of a gap between the time that current research knowledge
become available and its application to care. There is a delay in adopting useful procedures
and in discontinuing ineffective or harmful ones.
Assimilating Evidence into Practice
Assimilating scientific evidence into practice requires keeping up-to-date through reading
extensively, attending courses, and using the internet to search for published scientific
articles. Keeping current with relevant research is challenging. Substantive advances made in
the knowledge of clinical dentistry Periodontics have not been translated into practice or fully
applied to allow patients to receive the total benefits.
Advantages of Evidence BasedApproach
Evidence based approach is:
1. Objective
2. Scientifically sound
3. Patient focussed
4. Incorporates clinical experience
5. Stresses good judgement
6. Is thorough and comprehensive
7. Uses transparent methodology
Process of Evidence BasedDecision Making
1. Asking good questions – PILO Process
2. Searching for and acquiring evidence
a. Levels of evidence
b. Sources of evidence – primary and secondary
3. Appraising the evidence
4. Evaluating the outcome
Asking Good Questions
The first step in searching for relevant evidence is to frame the appropriate questions. A
question should consist of 4 parts:
P: Population or patient problem
I: Intervention
C: Comparison
O: Outcome

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E.g., “Fro a patient with a 5 mm pocket *actisite* as compared to *atridox* greater gain in
CAL? ”
P: (Problem) 5 mm pocket
I: (Intervention) Actisite
C: (Comparison) Atridox
O: (Outcome) Gain in CAL
a. Focusing on the most important single issue or outcome.
b. Facilitating computerised search by identifying the key terms used in the search.
c. Identifying the problem, the result, and the outcomes related to the specific care provided
to that patient. This allows identification of the type of evidence required to solve the
problem as well as considerations for measuring the effectiveness of the intervention.
Searching for and acquiring evidence
All valid researches that answer a specific question is considered evidence.
a. Levels of Evidence.
The highest level of evidence – “gold standard” – is the systemic review and meta-
analysis using two or more RCT (Randomised Controlled Trials)
They are considered the gold standard because of their strict protocols to reduce bias.
Systematic reviews provide a summary of multiple research studies that have
investigated the same specific question. They use explicit criteria for retrieval,
assessments and synthesis of evidence from RCTs.
Meta analysis is a statistical process often used with systematic reviews. It involves
combining statistical analysis of several individual studies into one analysis.
Meta Analysis &
SystematicReview
RCTs
CohortStudies
Case Control Studies
Case Reports
Ideas,Editorials,Opinions
Animal Research
In-vitro (test tube) Research

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Levels of Clinical Evidences
Levels are based on the ability to control bias and to demonstrate cause and effect.
Progressing up the pyramid, the number of studies and correspondingly the amount of
available literature decrease, while at the same time their relevance in answering clinical
questions increases.
The level of evidence is related to the type of questions asked, such as those derived from
issues of therapy or prevention, diagnosis, etiology and prognosis.
E.g.,
 Highest level of evidence for questions on therapy: SRs of RCTs
 Highest level of evidence for questions on prognosis: SRs of inception cohort studies
Type of question related to type of method and level of evidence
Question Type Methodology of Choice Question Focus
Therapy &
prevention
SR of RCTs
SR of cohort studies
Allows for comparison between intervention
and control groups
Diagnosis SR of prospective
cohort studies
Compare tests with a reference or gold standard
test
Etiology,
causation, harm
SR of prospective
cohort studies
Compares a group exposed to a particular agent
with an unexposed group
Prognosis SR of retrospective
cohort studies
Follows progression of a group with a particular
disease and compares with a group without the
disease
Sources of Evidence
Primary: Original research publications.
Secondary: Systematic reviews, meta-analysis, evidence based article reviews and clinical
guidelines synthesised from primary sources.
Primary Sources
Biomedical database such as Medline (MedPub) and EMBASE provide access to both
primary and secondary research.
The PICO question provides the foundation for the search terms used in the database.
Secondary Sources
a. Summaries of systematic reviews and research articles. Evidence based journals such
as Journal of Evidence Based Dental Practice and Evidence Based Dentistry provide
concise and easy to read summaries of selected biomedical literature.

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b. Clinical practice guidelines and protocols. Guidelines defined by the Institution of
Medicine in 2000 as “systematically developed statements to assist practitioner and
patient decisions about appropriate health care for specific clinical circumstances.”
c. AAP position papers, statements and parameters of care: the AAP regularly maintains
treatments, products and concepts to ensure that they are still the best available and
publish the results in their position papers.
Comparison of systematic review and literature review
Characteristic Systematic Review Literature Review
Focus of review Specific or narrow focus Range of issues or broad focus
Who conducts it Multi-disciplinary team Individual
Selection of
studies to
include
All the studies that meet pre-
established criteria. Bias is
minimised
Inherent personal bias with lack of
criteria.
Reported
findings
Description of study design,
subjects, length of trial,
outcome measures.
Description in nature, reporting the
outcome of studies rather than their
study designs.
Synthesis of
selected studies
Results are statistically
combined (meta-analysis)
Studies are reported without combining
data.
Main results Summary of trials; total
number of subjects, definitive
statements about findings in
relation to objectives and
outcome measures
Summary of the findings by author in
relation to purpose of literature review
and specific objective.
Appraising the Evidence
It is necessary to review the evidence to determine if the methods were conducted rigorously
and appropriately. International evidence-based groups have made this easier by developing
appraisal forms and check-lists that guide the user through a standard series of “Yes/No”
questions to determine the validity of the individual study or systematic review.

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Guidelines that can be used for critical analysis
Guide Purpose
CONSOERT statement (Consolidated
Standards of Reporting Trials)
To improve the reporting and review of
RCTs
QUOROM (Quality of Reporting of Meta-
Analysis)
To improve the reporting and review of
SRs
CASP (Critical Appraisal Skills Program) To review RCTs, SRs and other types of
studies
Evaluating the Outcomes
The final steps in evidence based decision making are to evaluate the effectiveness of the
intervention and clinical outcomes and to determine how effectively teh EBDM process was
applied. This can be achieved through self evaluation, by questioning the effectiveness of
each step.
Assessing Evidence
A large number of research articles are published every year. This makes it necessary to
assess the evidence for their clinical relevance. This is done by using 12 different tools:
1. Scepticism
2. Deductive reasoning
3. Inductive reasoning
4. Cause preceding effect
5. No change in hypothesis
6. Clinically relevant pre-trial hypothesis
7. Size of association
8. Contradictory studies
9. Randomisation
10. Non-randomised evidence
11. Placebo effect
12. Conflict of interest
Scepticism
In 1900, William Hunter developed the idea that microorganisms were responsible for a wide
variety of systemic conditions. He believed that removal of the causative organisms through
tooth extraction resulted in the improvement in the systemic health. Since this theory
explained a wide range of diseases for which there was no explanation at that time, it became
widely accepted and led to wholesale extraction of teeth.
The focal infection theory fell into disrepute in the 1940s and 1950s when widespread
extraction failed to reduce or eliminate the systemic condition.

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Many of the precepts of the focal infection theory are being reviewed today. However, in
order for the hypothesis not to fall into disrepute again, the theories should be viewed with
scepticism and there must be no unsubstantiated attributions, no theories without evidence.
Evidence on how to cure, manage, or prevent chronic diseases is notoriously contradictory,
inconsistent and unreliable. Three reasons why most studies on Periodontics are inaccurate:
1. Identifying a successful treatment for chronic diseases is challenging. It is estimated
that less than 0.1% of tall treatments are effective, thus the most so called effective
treatments identified in clinical trials turn out to be ineffective or even harmful.
2. Most chronic diseases are complex and include both environmental and genetic
causes. Incomplete and mistaken understandings of chronic disease etiology can lead
to a cascade of wrong turns in the exploration of possible diagnosis, prognosis and
treatment.
3. Poor scientific methodology employed by researchers leads to inaccurate results.
Deductive reasoning
Causal chain thinking which implies: if A causes B and B causes C than A causes C.
This system of deductive reasoning or application of logic was developed by the Greeks and
is appropriate in mathematics – not in medicine or dentistry.
Loe, in a classic study in 1965 on experimental gingivitis, showed that plaque is the etiologic
factor responsible for gingivitis. It is also well known that Periodontics is always preceded by
gingivitis. But, saying that plaque leads to gingivitis would be over-simplifying the
pathogenesis of the disease.
Another example of why logic is not ** in our field is: Antibiotics are used to treat bacterial
infections. Periodontitis is a bacterial infection. Having said this, indiscriminate use of
antibiotics in treating periodontitis is not justified. Increased use of antibiotics when not
required has led to development of resistance on a global scale.
Inductive reasoning
Rational thought or inductive reasoning is based on systematic experiments. Galileo is
typically credited with the start of systematic experimentation in physics. Three systematic
experiments used in clinical research:
1. Core control study
2. Cohort study
3. Randomised control trial
In order to understand the study designs, we must first understand the terms ‘exposure’ and
‘end point.’
‘Exposure’ refers to a suspected etiologic factor or an intervention such as treatment or a
diagnostic test.

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‘End point’ refers to the outcome of disease, quality of life measures, or nay type of condition
that may be of interest tin clinical studies.
Randomised Controlled Trials
Individuals are randomly assigned to different exposures and monitored longitudinally for the
end point of interest. If the end points frequency differs between the exposure groups, an
association between the exposure and the end point is present.
An example is a 3 years study conducted by Greene et.al. in 1971on 1248 general telephone
workers in California. The study was carried to determine whether progression of gingival
inflammation is reduced in an oral environment in which high levels of hygiene are
maintained. Subjects were given a series of oral prophylaxis treatments combined with oral
hygiene instructions (first exposure group.) Subjects in the control group received no
attention from the study team except for annual examinations instructions (second exposure
group.)
After 3 years, increase in plaque and debris in the control group was 4 times that of
experimental group (end point.) Hence there is a difference in end point frequency (4 times)
between the exposure groups, an association between oral prophylaxis + OHI (exposure) and
(end point) decrease in plaque and calculus is present.
RCT is the gold standard design in clinical research. It is level 1 or the best level of evidence.
Cohort Study
Exposed individuals are compared to non-exposed individuals and monitored longitudinally
for end point occurrence. If the end point differs between the exposed and non exposed
individuals, an association between exposure and end point is present.
Loe et.al. conducted a longitudinal investigation to study the natural development and
progression of periodontal disease. The first study group, established in Oslo, Norway, in
1969, consisted of 565 healthy male non-dental students and academicians between 17 and 40
years of age. This population had experienced maximum exposure to conventional dental
care throughout their lives (exposed individuals.)
A second study group, established in Sri Lanka, in 1970, consisted of 480 male tea labourers
between 15 and 40 years of age. The workers had never been exposed to any program
relateive to prevention or treatment of dental diseases (non-exposed individuals.)
The results of this study are interesting. The Norwegian group, as the members approached
40 years, had a mean individual loss of attachment of slightly above 1.5 mm while that for
the Sri Lankan group was 4.5 (end point.)
Thus, the end point frequency differs between the exposed (1.5) and the unexposed (4.5)
individuals and an association between exposure (preventive dental programs) and end point
(reduced attachment loss) exists.

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A cohort design study is the optimal study design in non-experimental clinical research or is
level-2 evidence.
Case Control Study
Cases (individuals with the end point interest) are compared with controls (individuals
without the end point of interest) with respect to the prevalence of the exposure. If the
prevalence of exposure differs between cases and controls, an association between the
exposure and the end point is present.
This is the most challenging study design to use and is called level 3 evidence.
An example would be if patients with oral Sub-mucus Fibrosis (cases) are compared with
patients without OSMF (controls) with respect to the prevalence of areca nut chewing
(exposure.) Unlike deductive reasoning, where associations are either true or false, such
absolute truths cannot be achieved with systematic experiments. Conclusions based on
controlled study designs are always surrounded by a degree of uncertainty.
Cause preceding effect
This refers to the typical dilemma of whether the egg came first or the chicken did.
Temporality or the cause has preceded the effect is necessary to claim causality.
Walter Loesche in 1979 gave the specific plaque hypothesis which states that only certain
plaque is pathogenic and its pathogenicity depends on the pressure or increase in specific
micro organisms. This concept predicts that plaque harbouring specific bacteria pathogens
results in a periodontal disease because these organisms produce substances that mediate the
destruction of the host tissues.
According to the ecological theory given by PD March, aerobic organisms are harboured in a
healthy gingival sulcus. As the pocket deepens, the sub-gingival environment changes and
favours the growth of anaerobes. According to this theory, the formation of a pocket is
necessary for the growth of anaerobes and not the other way round.
Hence, it is hard to say with certainty which is the cause and which the effect is.
No change in hypothesis
A well defined hypothesis should be established at the start of the study and this should be
adhered to for the rest of the study. No changes can be made in the hypothesis once the study
is started.
a. Modifying study sample definition: once the study sample is decided, this sample
population should not be tampered with. E.g., if a certain periodontal treatment is
evaluated, the results should be evaluated even on the teeth which are lost eventually,
the original sample considered should not be altered for any reason. Results of
improper subgroup analysis are meaningless when establishing causality.
b. Modifying exposure definition: exposure defined in the hypothesis should not be
changed during the study. E.g., if the efficacy of a new mouth wash be tested against

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the gold standard, chlorhexidine and a pseudo cannot be changed from saline to water
assuming it does not make too much a difference. Exposure decided in the original
study design must not be changed.
c. Modifying end point definition: almost all major trials specify one primary end point
in the pre-trial hypothesis. Any modification of this end point during or after the trial
is a cause for concern. E.g., if the original study is checking the effect of SRP on
decreased pocket depth, the end point cannot be changed to decrease in gingival index
scores if no change in pocket depth is found.
Deviating from the pre-trial hypothesis is called “data torturing.” Manipulating the
data to take only the values which prove our point is called “procrustean data
torturing.” Just as the Greek Procrusteus fitted guests perfectly to his guest bed either
through bodily stretching or chopping of the legs to ensure the body height and the
bed length correspond.
Clinically relevant pre-trial hypothesis
Trials on clinically relevant questions dramatically change clinical practice. Usually,
clinically relevant questions share 4 important characteristics of the pre-trial hypotheses:
1. A clinically relevant end point (outcome in PICO question)
2. Relevant exposure comparisons (intervention and control in PICO question)
3. A study sample representative of real world clinical patients (patient defined in PICO
question)
4. Small error rates
A clinically relevant end point
Two clinically relevant end points are recognised.
True End Points: Tangible outcomes that directly measure how a patient feels, functions or
survives like tooth loss which affects quality of life and ain which can be felt.
Surrogate End Points: Intangible outcomes used as a substitute for a true end point. E.g.,
reduction of pocket depth or gain in clinical attachment level.
The first requirement for a clinically relevant study is the pre-trial specification of a true end
point.
Relevant exposure comparisons
A clinically relevant exposure comparison implies:
- Absence of contrived control groups
- Use of a placebo control group when appropriate
An example for irrelevant exposure comparison would be comparing 0.12% chlorhexidine
with 0.05% chlorhexidine mouth wash when it is known that 0.05% mouthwash is
ineffective.

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Moreover, a conclusion drawn for one particular type of exposure connot be translasted to
that of apparently closely related exposures. E.g., if a study determines the effect of
doxycycline on sub antimicrobial doses, it cannot be assumed that a related drug like
microcycline would have to same effect.
Representative Study Sample
The larger discrepancy between the study sample and the patient one seeks to treat, the more
questionable the applicability of the study’s conclusion becomes. Studies done on population
similar to the patients we treat are considered relevant.
E.g., most of the studies implicating Herpes Simplex Virus in the pathogenesis of
periodontitis have been conducted on HIV patients. Hence, there is a controversy regarding
HSV as an etiologic factor in periodontitis.
Small error rates
Type-1 error rate: Likelihood concluding that there is an effect when in truth there is no
effect; 1% or 5%.
Type-2 error rate: Likelihood of concluding that there is no effect when in truth there is an
effect; 10% or 20%
Size of association
The larger the association, the less likely it is causal; like 80% bone fill after the use of
DFDBA would leave no doubt as to the association between DFDBA and bone fill whereas
gain in CAL by 0.1 mm after local drug delivery would imply a doubtful association.
Size of association can be calculated by calculating the odds ratio – the probability that the
event happens divided by the probability that the event does not happen.
End Point
Failure Success
Exposure Experimental A B
Control C D
Odd ratio = ad / bc
The size of odds ration ranges between 0 and infinity. An odds ratio larger than 1
(experimental failure X success of control is greater ad) indicates a harmful effect.
An odds ratio smaller than 1 (experimental success X control failure – bc is greater) means a
protective effect.
Contradictory studies
Studies disproving a hypothesis have greater value than those which accept it. E.g., for many
years root conditioning with citric acid and tetracycline were considered to prevent epithelial
migration, favour fibroblast adhesion and thus help in regeneration. Marrioti et. al. in 2003

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published a position paper refuting the fact that these agents aid in regeneration and said that
the only use of these agents could be in removing the smear layer on the root surface.
Another reason for many studies establishing an association is not present is because of the
presence of confounding factors. E.g., smoking and diabetes mellitus are confounding factors
for periodontitis.
In randomised studies confounding is not an issue because randomisation balances known
and unknown confounders cross the compared groups with a high degree of certainty. E.g., if
there are equal number of smokers in the experimental and the control group there is no bias.
In non-randomised studies, the following questions concerning confounding arise:
1. Whether all the confounders have been included: multiple confounders need to be
included in statistical analysis. An association unadjusted for any potential
confounders is called a crude association. When the crude association is adjusted for
potential confounders, it is called an adjusted association.
2. Whether confounders can be accurately measured: potential confounders like smoking
and life style could be difficult to measure as discrepancies between what is measured
and the truth could lead to incomplete removal bias. The remaining bias is called
residual confounding.
Randomisation
 Creates heterogeneity.
 Takes over treatment assignment away from the physician.
 Leads to a situation in which patients are randomly assigned to treatments and if they
refuse treatment, they are still analysed as if they have received treatment.
Randomisation includes the following steps:
1. Subjects are enrolled into a study prior to randomisation; important baseline disease
characteristics are recorded and provided to an independent person or organisation.
This step ensures that baseline information is available for every patient who will be
randomised.
2. An independent person or organisation randomly assigns subjects to a treatment and
informs the clinician regarding the treatment assignment. The concealment of the
randomisation process ensures that clinicians cannot crack the code and that they will
enrol only those patients they think are suited for the treatment that will be assigned.
3. The outcome in the subject is available regardless of the follow up time or compliance
and according to the treatment assigned – not the treatment received. Factors related
to compliance and unrelated to the treatment under investigation have a powerful
influence on the outcome measured. Deleting such non-compliant patients might lead
to biases.

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Non-randomised evidence
Ethical principles dictate that proposed interventions do more good than harm, that the
populations in whom the study will be conducted will benefit from the findings and that an
informed consent is obtained from enrolled subjects. E.g., studies on gene therapy using viral
vectors and studies on human subjects are difficult due to safety concerns. Sample size
considerations may prevent conduct of RCTs. The smaller the rates at which end points occur
in an RCT, the larger the required sample size will be. For rare events such as bacterial
endocarditis subsequent to a dental procedure or HIV conversion after exposure to an HIV
contaminated dental needle, RCTs may never be possible because the required sample sizes
are in the 100 thousands or millions of subjects.
Placebo effect
Placebo effect should be considered while evaluating studies to use as scientific evidence.
Placebo effects are the beneficial effects some patients experience by simply participating i a
study, by patient-physician interaction, by patients anticipation for improvement, or by the
patient’s desire to please the physician. A small controlled study in 11 patients showed that
placebo effects can cause changes in brain function, providing plausibility to the argument
that placebo effects may have biological effects. Due to such placebo effects, without mock
surgeries it would be impossible to tell whether the improvements observed in clinical trials
are caused by the placebo effects associated with the surgical procedures or by the
hypothesised active ingredients of the surgery itself.
Overall, sufficient evidence is available to suggest that placebo effects can be real and
measurable and that the magnitude of the effect may depend on the treatment under study and
the type of outcome evaluated.
Conflict of interest
Conflict of interest has been defined as “a set of conditions in which professional judgement
concerning a primary interest such as patient’s welfare or validity of research, tends to be
unduly influenced by a secondary interest.” Secondary interests may be financial, religious or
scientific beliefs, ideological or political beliefs, or academic interests. E.g., industry
sponsored studies 3.6 times as likely to have pro-industry conclusions as non-industry
sponsored studies.
Implementing Evidence BasedDecisions in Clinical Practice
Evidence based practice has been defined as improving treatment outcomes by using research
evidence along with clinical experience and patient preferences in making decisions about
individual patients.
Implementing evidence based decisions in clinical practice includes the following steps:
1. Managing uncertainty
2. Incorporating evidence into practice
3. Linking outcomes with diagnosis and treatment

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4. Implementing evidence based decisions
5. Change management
Managing uncertainty
Decision making is an important skill in clinical practice. This could be complicated in
Periodontics as establishing a prognosis is inherently imprecise.
There are psychological issues in making decisions, especially while facing clinical
uncertainties. Simply repeating old behaviour patterns is generally more comfortable than the
insightfulness needed to question one’s own actions and embrace change.
Another reason for our indecisiveness is that our classic elementary education has trained us
not to make decisions on our own, but to follow a prescribed set of rules. Most of us have
been educated under a pedagogical system of learning. In this system, the dominant teacher
disseminates known facts to the submissive students. Motivation is external, learning is not
generally applied and students are not encouraged to think and question but blindly accept
what is taught to them.
Andragogical theory is an adult form of learning and encourages students to apply their mind.
Andragogical theory states that adults learn best by internal motivation and have an urgency
to solve problems by drawing on existing knowledge. Adult learning is about discovering
what is known, accepting uncertainty, yet being able to apply new found knowledge
immediately.
Traditional dental education has generally been pedagogical in nature. A linear approach to
clinical decision making is followed.
Condition  treatment  outcome
Dentists including periodontists typically identify a presenting dental condition. E.g.,
periodontists conventionally believed that all cases with reduced width of gingiva require
gingival augmentation. But, Dorfman et.al. in 1980 showed that experimental sites which had
been grafted (FGG) and showed an increase of 4 mm of attached gingival showed no
difference in GI, PI and CAL as compared to control sites in whom periodontal care was
given every 3 months.
Thus, the linear or cook book approach to dental treatment could lead to successful outcomes
such as an increased width of the attached gingiva, but it raises the question of over
treatment. Traditional approaches which adhere to rules such as every patient with decreased
gingival width need to be treated need to be replaced with evidence from newer research
which employs a wait and watch policy. Only case with persisting inflammation or increasing
recession are in need of treatment.
Incorporating evidence into practice
Publication of research advances allowed practitioners to incorporate this evidence into
clinical practice. This process is known as science transfer.

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Dental practitioners, including periodontists, may bve aware of the current best evidence in
dentistry due to the sheer number of dental journals and the rate at which studies are being
published. This problem has been partly alleviated by the development of evidence based
journals or systematic reviews.
Searching for and critically appraising evidence are significant barriers facing dental
practitioners. When reading a scientific investigation, the dental professional should keep in
mind the following 3 questions:
1. What are the results?
2. Are the results valid?
3. Are the findings relevant to my patient population?
These questions form the basis of critical appraisal, the ability to access a study for clarity,
validity and generalisability. This skill has also been made easier by using critical appraisal
work sheets that can be downloaded from various website. These worksheets act as a guide to
help readers in the decision to use or discard evidence.
The effectiveness of the method used to disseminate evidence is also fo importance. Passive
diffusion of information and C&E lectures are less effective than small, interactive grop
work, problem-based learning, and practice-specific interventions,.
Linking outcomes with diagnosis and treatment
a. Outcome:
Dentistry is a treatment oriented profession and interventions are considered superior to
“watchful waiting.” This often leads to over-estimation of a patient’s risk of disease
progression and often leads to over-treatment.
Though periodontal disease may cause a significant morbidity and alter the quality of life
by causing mobility, abscess formation, pain, loss of teeth and difficulty in mastication.
Therefore, it is upto the astute clinician to decide when intervening becomes crucial and
when it is preferable to wait and watch.
b. Diagnosis:
Periodontal disease tends to be over-diagnosed by the novice practitioner, yet its
subtleties allow it to be under-diagnosed by experienced practitioners. Diagnosis has been
facilitated by assessing a patient’s susceptibility to dental disease. Scientific evidence has
now identified risks factors for both periodontal disease. Assessment of susceptibility
facilitates both diagnosis and prognosis. Treating before establishing a diagnosis or with a
misdiagnosis usually leads to poor decisions and ultimately unfavourable outcomes.
Unfortunately diagnosis has been under-emphasised in favor of technical skill
development at the undergraduate level.
c. Treatment:
Patients and dentists usually view dentistry as a treatment oriented profession that tends
to discount the diagnostic phase of dental care. Another form of bias, financial bias,
occurs when the compensation from more lucrative types of procedures unduly influence

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the decision making process. In Periodontics, surgical procedures are compensated at a
higher rate than non-surgical therapies and clinicians have a built-in incentive to provide
more costly services. This vulnerability is inherent in all the clinicians and they must keep
this in mind when making decisions about individual patients.
Ideally the phases that should be followed when a patient visits a dental clinic are:
Presenting condition  Assess disease  Establish diagnosis  Establish prognosis 
Evaluate need / level of intervention.
Implementing evidence based decisions
Decisions to intervene are critical and should be the third step in a four step process. A
diagnosis should be established prior to deciding to intervene. If diagnosis established, one
might decide to intervene depending on the evidence based pattern of decision making
described as follows:
Change management
Three main challenges lie ahead with the implementation of evidence based decisions:
a. Individual changes
b. Organisational changes
c. Allowing research findings to guide the decision making process
Condition
Diagnosis
Treatment
Outcome
No Treatment
No Diagnosis
Treatment No Treatment
Outcome

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Change can be implemented by
Recognising the need for change
Performing an organisational analysis and indentifying all the stakeholders
Including all the stakeholders in the process
Monitor and evaluate to ensure lasting change
Change management
An evidence based method closes the gap between clinical research and the realities of
practice by pro9vidign dental practitioners with the skills to find, efficiently filter, interpret,
and apply research findings so that what is known is reflected in the care provided. This
approach assists clinicians in keeping current with the conditions that a patient may have by
providing a mechanism for addressing gaps in knowledge to provide the best care possible.
Conclusions
• The principles of evidence-based healthcare provide
structure and guidance to facilitate the highest levels
of patient care.
• Evidence-based healthcare is not an easier approach to patient management, but
should provide both clinicians and patients with greater confidence and trust in their
mutual relationship
References
• Textbook of Periodontics ,10th edition Carranza.
• Textbook of Periodontics, 2nd edition Lindhe.
• Textbook of Community dentistry, Dr. Soben Peter
• Evidence based periodontics :A review. Ian needleman Perio 2000 vol 37 Feb 2005:
12-28.
• Evidence based periodontics systematic reviews and research quality David R. Moles
et al Perio 2000 vol 37 Feb 2005: 12-28.