Microleakage of human saliva in coronally unsealed obturated root canals in anaerobic conditions.

The purpose of this study was to determine the time required for anaerobic bacteria in natural human saliva to contaminate root-filled teeth. Thirty-two single-rooted teeth were cleaned, shaped, filled, and exposed to human saliva for 120 days. Teeth that had not leaked were subjected to polymerise chain reaction examination. Sixty-six percent of the experimental group were totally contaminated. A PCR examination revealed there was no contamination in the apical 3 mm of leakage-free teeth.