Salivary glucose levels and pH in healthy adults with dental caries

This study aimed to analyze salivary glucose levels and pH in relation to the intensity of dental caries in healthy, nondiabetic adults. The study was conducted on 61 patients who were assigned to individual groups based on dental examinations and the calculation of the decayed, missing, and filled teeth (DMFT) index. Group 1 (control) included 15 caries-free persons (DMFT=0). Group 2 consisted of 15 patients with low caries intensity (DMFT=6.4±1.3). Group 3 comprised 15 patients with moderate caries intensity (DMFT=10.9±1.8). Group 4 included 16 patients with high caries intensity (DMFT=19.2±3.6). Salivary glucose concentration was determined using a quantitative enzymatic method, while salivary pH was measured with a combined electrode. The mean salivary glucose levels in groups 1 and 2 were 2.39±0.62 and 3.28±0.92 mg/dl, respectively. The determined cut-off value for the highest glucose level associated with low caries intensity was 6.64 mg/dl. In contrast, the mean salivary glucose levels in groups 3 and 4 were 7.55±1.16 and 9.9±1.14 mg/dl, respectively, which were significantly higher than those in groups 1 and 2. Regarding salivary pH, the mean values in groups 1 and 2 were 7.19±0.15 and 7.12±0.20, respectively, while in groups 3 and 4, the mean salivary pH were 6.69±0.17 and 6.57±0.19, respectively. These values were significantly lower than the mean values in groups 1 and 2. The data presented here show that increased levels of salivary glucose above 6.64 mg/dl may indicate moderate to high severity of dental caries. Changes in salivary pH may result from the predominant metabolic activity of different species of oral bacteria, including arginolytic, ureolytic or acidogenic bacteria. These findings have important practical implications for monitoring and preventing dental caries.