Association between salivary factors and cariogenic bacteria in type-2 diabetes patients

Type-2 diabetes (T2DM) is a global epidemic. Among various complications of T2DM, dental caries is one of its preventable complications. This investigation was aimed to study the association between salivary factors and the growth of cariogenic bacteria in the saliva of T2DM patients. We measured the salivary glucose, saliva flow rate and its buffering capacity in T2DM patients (N = 100). Cariogenic bacteria in saliva were detected by using a Chair-side Test Kit. We also analyzed fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) in all the subjects. A large number of T2DM patients (78%) had high counts (>105 CFU /ml) of streptococcus mutans in their saliva whereas high counts of lactobacilli were observed only in 42% patients. We observed significant associations between streptococcus mutans load and saliva flow rate, saliva buffering capacity and glycemic control however these variable did not show any significant association with lactobacilli. Hypo-salivation, high salivary glucose and poor glycemic control promoted the growth of streptococcus mutans in the saliva of T2DM patients. In conclusion, salivary factors play important roles in controlling the salivary status of cariogenic bacteria. Thus, an adequate oral health and proper glycemic control could help in abolishing the caries risk and its complications.