Comparison of Salivary Peroxidase System Components in Caries-Free and Caries-Active Naval Recruits

Abstract

Measurements of flow rate, pH, hypothiocyanite, thiocyanate, and salivary peroxidase activity were made for unstimulated (drooled) whole saliva samples from 29 caries-free and 29 caries-active naval recruits. No significant differences were found between the two groups of subjects for any of these variables. Thus, single point measurements of static properties of saliva do not reveal significant correlations between caries incidence and concentrations of salivary peroxidase system components. However, the results did provide strong support for the concept that the salivary peroxidase system is active in vivo. Statistical analyses showed significant negative correlations for hypothiocyanite with salivary peroxidase activity. These correlations are consistent with in vitro biochemical studies which show that the generation of hypothiocyanite in saliva is associated with a decrease in enzyme activity. Furthermore, smokers had significantly elevated thiocyanate and hypothiocyanite compared to nonsmokers. These elevations are also consistent with in vitro studies which show that when the salivary peroxidase system is activated additional supplements of thiocyanate produce increased generation of hypothiocyanite.