The Clinical Practice Guidelines in the American Dental Association's Center for Evidence-Based Dentistry provides access to a curated collection of current systematic reviews, critical summaries and practice guidelines.
You should also turn to a database like PubMed when you do not find a guideline on your topic in the ADA's Clinical Practice Guidelines. Search first for a systematic review and then for individual research studies.
The Cochrane Collaboration is an international, non-profit, independent organization that publishes systematic assessments of evidence of the effects of healthcare interventions. Cochrane systematic review authors follow a published procedure that has become the gold standard for systematic reviews of interventions. Cochrane Review citations are included in the ADA Evidence Database and are indexed in PubMed.
To learn more about how the Cochrane Collaboration works see the Cochrane Collaboration About Us page.
Go to PubMed and enter your search words for the clinical question.
Finding Systematic Reviews
Finding Randomized Controlled Trial (RCT)
Finding Cohort Studies
Finding Case-Control Studies