Evidence Based Dentistry

1. Evidence Based Dentistry
Rasha Adel Ragab
Assistant Lecturer – Cairo University

2. Evidence-Based Medicine (EBM)
The integration of the best research evidence
with our clinical expertise and our patient’s
unique values and circumstances.

3. the American Dental Association (ADA) defines
"evidence-based dentistry" (EBD) as:

5. “to encourage the ordinary dental
practitioner in primary dental care to
look for and make sense of the evidence
available in order to apply it to every day
problems.”

8. ● Production of evidence through research and
scientific review
● Production and dissemination of evidence-based
clinical guidelines
● Implementation of evidence-based, cost-effective
practice through education and management of
change
● Evaluation of compliance with agreed practice
guidance through clinical examination and
outcomes focused incentives.

11. Ask
Acquire
FIVE STEPS OF EBD
Assess
Apply Appraise

12. 1. Ask
Asking a Clear and Focused Questions
Use PICO to Create a Search Question
Population / Intervention / Comparison / Outcome

14. 2. Acquire
Finding the Evidence

15. Online databases; MEDLINE via PubMed;
http://www.ncbi.nlm.nih.gov/pubmed,

16. Are topical fluoride treatments effective in
reducing caries in children?”
P: Children
I: Topical fluoride
C: No topical fluoride
O: Caries

17. What constitutes the highest
levels of evidence ?

19. What is the difference between; ….

21. “Systematic Review”
1. Collect all published evidence on a question
2. Rank on value-based score card
• Human > animal>laboratory
• Prospective>observational>retrospective>case report
• Double blind>cohort comparisons
• Controlled>non controlled
• Randomized > non randomized
• Replicated>non replicated
“Gold Standard”
double blind, randomized, controlled clinical trials

22. “Meta analysis”
1. Collect results and analysis from all
available studies
2. Re-analyze pooled results based
upon common “meta” statistics
3. Develop an overall conclusion based
upon the overall grouped “meta
analysis”

23. Possible Outcomes
1. The evidence supports a particular treatment as being
effective.
2. The evidence does not support a particular treatment as
being effective.
3. The evidence appears to support, but is not completely
definitive for a particular treatment.
4. There is inadequate evidence to support or refute a particular
treatment at this time.
Unfortunately, most dental systematic
reviews result in either 3 or 4

24. 3. Appraise
Critically Appraising the Evidence
Critical appraisal is the process of carefully
and systematically examining research to judge
its trustworthiness, and its value and relevance
in a particular context.

25. To assess whether a reported
piece of research is good enough
to be used in decision making

26. Trustworthiness
Validity
Results
Relevance

27. Validity
• Validity defines the strength of the final
results and whether they can be regarded as
accurately describing the real world.

28. Validity
Internal External

29. When critically appraising research;
it is important to first look for biases in the
study; that is, whether the findings of the study
might be due to the way the study was designed
and carried out, rather than reflecting the truth.
A study which is sufficiently free from bias is said
to have internal validity

30. Key sources of bias in clinical trials
Selection bias
Biased allocation to comparison groups
Performance bias
Unequal provision of care apart from treatment under
evaluation
Detection bias
Biased assessment of outcome
Attrition bias
Biased occurrence and handling of deviations from protocol
and loss to follow up

31. External validity
(Outcome)
Asks the question of generalizability: To what
populations, settings, treatment variables and
measurement variables can this effect be
generalized?”

32. Reliability
• Reliability describes the repeatability
and consistency of a test.
• Results; Pvalue: the probability of chance of
error, should not exceed 0.05

33. Clinical Relevance
 Outcome (External validity)
Applicability... Increase with inc. ext. validity
Cost… Inc. cost  dec. ext. validity

34. 4. Apply
Use the best identified valid and relevant
evidence in patient care

35. 5. Assess
Assess how well the previous steps worked