Parotid Saliva Flow Rates in Caries-Resistant Naval Recruits

¹ Naval Dental Research Institute, Naval Training Center, Great Lakes, Illinois

A longitudinal study was carried out to determine the parotid flow rate of 50 young naval recruits that had a history of no dental decay at the beginning of the study. Twentyseven men developed at least one lesion during the year's observation period. The subjects that remained caries-free throughout the study had a mean parotid flow rate of 20.5 ml./20 minutes compared with 17.4 ml./20 minutes for those developing caries. This difference was of borderline significance. The mean for both groups was 18.9 ml./20 minutes.

Although the flow rate for an individual was not diagnostic for his caries status, a definite relationship was shown to exist between the parotid flow rate and caries incidence.

Analysis of the diurnal variation of the parotid flow rate showed a decrease for approximately 2 hours after the noon meal.

When caries did develop the third molars had the highest rate of decay, followed by the second and first molars. Eighty percent was on the occlusal surface.