Role of saliva proteinase 3 in dental caries

Research Summary

Dental caries: A protein in saliva may fight cavities

Higher levels of proteinase 3 (PR3) in saliva are associated with lower levels of dental caries. Other salivary proteins have previously been shown to influence dental health. Ping Zhang, Xue-Dong Zhou and co-workers at the State Key Laboratory of Oral Diseases, Sichuan University, China, analyzed salivary proteins and the pH of saliva collected from 128 healthy six-year-old children. Caries-free children showed significantly higher levels of PR3 than those with caries. Salivary pH was not significantly associated with caries, but a higher pH was significantly associated with higher PR3 levels. The researchers investigated whether PR3 showed activity against Streptococcus mutans, a bacterium commonly associated with cavities. High levels of PR3 inhibited the growth of S. mutans. Further studies will be required to determine whether PR3 can be used to help prevent cavities.