Co-relationships between glandular salivary flow rates and dental caries

Abstract

Objective: This study was designed to evaluate the relationship of age, gender, ethnicity and salivary flow rates on dental caries in an adult population using data collected from the Oral Health San Antonio Longitudinal Study of Aging (OH: SALSA).

Background: Saliva is essential to maintain a healthy oral environment and diminished output can result in dental caries. Although gender and age play a role in the quantity of saliva, little is known about the interaction of age, gender and ethnicity on dental caries and salivary flow rates.

Materials and methods: Data from the 1147 participants in the OH: SALSA were analysed. The dependent variables were the number of teeth with untreated coronal caries, number of teeth with root caries and the number of coronal and root surfaces with untreated caries. The independent variables were stimulated and unstimulated glandular salivary flow rates along with the age, sex and ethnicity (e.g. European or Mexican ancestry) of the participants.

Results: Coronal caries experience was greater in younger participants while root surface caries experience was greater in the older participants. Coronal caries was lower in the older age groups while the root caries experience increased. Men had a statistically significant (p < 0.02) higher experience of root caries than women. Values for unstimulated and stimulated parotid salivary flow rates showed no age difference and remained constant with age, whereas the age differences in the unstimulated and stimulated submandibular/sublingual salivary flow rates were significant. The mean number of teeth with coronal and root caries was higher in Mexican-Americans than in European-Americans.

Conclusions: Over one-fourth of the adults between the ages of 60 and 79 have untreated root caries over one-third having untreated coronal caries. Lower salivary flow rates play a significant role in both the number of teeth and the number of surfaces developing caries in these adults. Women and individuals of European-American ancestry experience less caries.

Keywords: ageing; caries; ethnicity; saliva.