Methods: : Two information databases, MEDLINE and Scopus, and reference books on endodontics were explored to ascertain the related studies. From 672 articles found 41 were accepted after critical appraisal and 11 were excluded because of methodological difficulties. The data from the 30 remained studies was analyzed by the version 9 Stata software.
Results: The meta-analysis demonstrated that 52.9% of subjects and 5.9% of teeth included in the study have apical periodontitis and that the prevalence of the disease in the root canal treated teeth is 37.8%. The prevalence of apical periodontitis appeared to be directly related to the age and inversely related to the human development index in countries. The meta-analysis also indicated that the root canal treated teeth were 16.7 times more likely to develop apical periodontitis than the untreated ones.
Conclusions:
Apical periodontitis is a common disease in all societies. 52.9% of subjects and 5.9% of teeth included in this study appeared to have apical periodontitis. Apical periodontitis is also highly prevalent in the root canal treated teeth (37.8%). The prevalence of the disease is directly related to age and inversely related to human development index in the countries.