Dental Caries and Streptococcus mutans Prevalence in Cancer Patients with Irradiation-Induced Xerostomia: 1–13 Years after Radiotherapy

Abstract

In this cross-sectional study, 9 of 34 irradiated patients and 4 of 5 preradiation patients had 1 or more carious lesions at the time of examination. The magnitude of S. mutans infection was determined from multiple samples of dental plaque taken from different anatomic sites. S. mutans was detected in 82% of the irradiated patients and 100% of the preradiotherapy patients. Although S. mutans was widely distributed throughout the dentition of both groups, the mean proportion of S. mutans relative to the total streptococci in interproximal samples was significantly higher in the irradiated patients. In the irradiated group without current caries, S. mutans prevalance was inversely related to the number of elapsed years postradiotherapy.