THE RELATIONSHIPS AMONG FLUORIDE, CARIOGENIC ORAL FLORA, AND SALIVARYFLOW-RATE DURING RADIATION-THERAPY

Changes in the quantity of Streptococcus mutans, lactobacillus species , and yeast Candida species were assessed in a cancer population under going head and neck radiation. The purpose of this study was to evalua te the effectiveness;of a:custom vinyl tray-applied fluoride gel to co ntrol cariogenic bacteria in a group experiencing hyposalivation becau se of radiation treatment. Twenty-two subjects participated in the stu dy and served as their own controls. Whole resting and whole stimulate d saliva were collected at weekly appointments beginning 1 week before and concluding 4 weeks after radiation therapy. Colony-forming units per mL of Streptococcus mutans and Lactobacillus species and semiquant itative counts of Candida species (0 = none; 1 = light; 2 = moderate; 3 = heavy) were determined from collected saliva. All patients were pr ovided with custom vinyl vacuform mouthguards to be used daily with ne utral fluoride gel (1.1% sodium fluoride). Whole stimulated and restin g saliva productions decreased by 36.67% and 47.9%, respectively, by t he end of 1 week of radiation therapy, and they remained low No signif icant changes in cariogenic oral flora were seen during and early afte r radiation therapy despite xerostomia. However, colonization by Candi da albicans increased during radiation therapy for oropharyngeal cance rs. Findings from this study suggest that changes in cariogenic flora may be suppressed through the use of daily topical neutral sodium fluo ride gels and that colonization by Candida albicans increase during ra diation therapy.