Flow rate, sodium and potassium concentration in mixed saliva of complete denture-wearers

Flow rate, sodium and potassium concentrations in stimulated mixed saliva obtained from eleven elderly (mean age 63) inexperienced denture-wearers, were determined. Salivary samples were collected at four different dental stages: 1. Before tooth extraction. 2. After tooth extraction. 3. Three weeks after wearing newly constructed complete dentures. 4. Following one year of denture wearing. Plasma electrolytes were included for comparison. The salivary sodium and potassium concentrations varied from stage to stage without showing corresponding variations in sodium and potassium in the blood. This points to selective action and an active transport system in the salivary cells. The mean flow rate and salivary electrolyte concentration showed a definite significant rise following the wearing of new complete dentures as compared with the previous dentulous and edentulous stages (Period A, non-denture-wearers). The mean flow rate was 2 ml/min after denture-wearing compared to 0.75 ml/min at the dentulous and edentulous stage (Period A). The stimulant effect represented by the dentures was found to be even more pronounced after one year. Mean sodium and potassium concentration at Period A were at levels of 5.50 and 13.67 mequiv./l respectively, as compared to levels of 23.72 and 19.40 mequiv./l respectively, after insertion of dentures. The difference was significant at a level of P less than 0.005. Although sodium concentration correlated well with flow rate, potassium concentration did not show any correlation with variations during secretion, following the wearing of dentures.