Objective: The activities of proteolytic enzymes in saliva were assayed to determine whether they were related to caries sensitivity and gender in the children.
Methods: Fluorometric and photometric methods were applied. Three enzymes included leucine amino peptidase, dipeptidyl peptidase IV and trypsin-like proteinase.
Results: 1. Only dipeptidyl peptidase IV and trypsin-like proteinase were demonstrated in saliva, they were obviously lower than those in dental plaque (P < 0.05); 2. The activities of proteolytic enzymes of male and female children as well as caries-active and caries-free children showed no difference.
Conclusion: Proteolytic enzymes play little role in caries formation of deciduous tooth.