Association between childhood obesity, salivary adiponectin, and total dental caries experience (dmft + DMFT) in children: a cross-sectional study

Childhood obesity and dental caries are among the most prevalent chronic conditions, but their biological interplay remains poorly understood. This study aimed to investigate the associations between childhood obesity, salivary adiponectin levels, and dental caries. In this comparative cross-sectional study, 120 children aged 7-12 years were recruited and classified into two groups: Group 1 (body mass index (BMI) percentile < 85; underweight or normal-weight, n = 60) and Group 2 (BMI percentile ≥ 85; overweight or obese, n = 60). The dental caries experience was recorded using WHO criteria for primary (dmft) and permanent (DMFT) scores. Unstimulated whole saliva samples were collected, processed, and analyzed for adiponectin concentrations using an ELISA assay. Dietary behaviors (sugar intake, consumption of acidic or pickled foods, and dairy intake) and oral hygiene practices were assessed. Student t-test, Mann-Whitney test, Spearman's correlations, and multivariable linear regression were conducted. Overweight/obese children exhibited significantly lower salivary adiponectin levels (2.49 ± 0.39 vs. 2.84 ± 0.43 ng/mL; P < 0.001) compared to their normal-weight peers and significantly lower total dental caries scores compared with normal-weight peers (5.05 ± 2.46 vs. 7.37 ± 3.25; P < 0.001). Salivary adiponectin was inversely correlated with BMI (Spearman's correlation coefficient (ρ) = -0.39) and dental caries (ρ = 0.14). Obese children showed lower salivary adiponectin levels but unexpectedly had lower dental caries scores than their normal-weight peers. These findings reinforce the multifactorial nature of pediatric oral health and highlight the need to integrate metabolic, behavioral, and environmental factors into preventive strategies.