Evaluation of oral health related to body mass index

Poor oral health has previously been related to high body mass index (BMI). We aimed at exploring the link between BMI and several oral health markers, after adjustment for dietary patterns and plasma insulin, both of which could act as mediators.

Dental examination was performed in a sample of 186 French subjects aged 35-64 years and selected from the general population to assess number of missing teeth, periodontitis, clinical attachment loss (CAL), probing pocket depth (PD), gingival index (GI) and plaque index (PI). Data collection also included a food-frequency questionnaire. BMI (considered as outcome variable) was categorized into quartiles, and as BMI<25; 25 ≤BMI<30; and BMI ≥ 30 kg m(-2) .

After adjustment for age, gender, education level, smoking, physical activity, energy intake and C-reactive protein, BMI was statistically associated with missing teeth, PD and PI, but not with CAL, GI or periodontitis. After additional adjustment for 'high-carbohydrate' diet and plasma insulin or HOMA (homeostasis model assessment) index for insulin resistance, the statistical relationship between BMI and oral variables remained significant only for PD and PI.

Plaque index, reflecting dental plaque, and PD, closely linked with periodontal inflammation and infection, are statistically associated with high BMI and obesity, independently of dietary patterns and insulin resistance.