In our daily practice, we think about the diagnosis of our patient and get into a situation wherein we have to make a clinical decision. Diagnosis and treatment come from the knowledge and experiences that each dentist should have, but sometimes, we can have doubts on our decisions. "On what evidence did I make such decision? Was that really right?" Drawing our attention these days as a possible answer to this question, evidence-based dentistry seeks to apply the best available evidence gained from the scientific method to medical decision making. To make a good decision, the strength of evidence is assessed. Specifically, randomized controlled trial, systematic review, and meta-analysis are considered the highest level of evidence; cohort study, case control study, case series, animal study, bench test, and biological plausibility follow. With the approach of evidence-based dentistry, we can make objective, scientifically sound clinical decisions. It is also patient-oriented, incorporating clinical experiences and stressing good judgments; thorough and comprehensive, it uses transparent methodology. That is the reason evidence-based dentistry can be better than other assessment methods when we make a clinical decision in modern dentistry.