Association between gastroesophageal reflux disease symptoms, dental health, and cariogenic microorganisms in the oral cavities of children

Background The acidic nature of gastric refluxate and the aciduric properties of cariogenic microorganisms may influence the oral microbial environment in children with gastroesophageal reflux disease (GERD). Streptococcus mutans and Streptococcus sobrinus are among the primary bacteria associated with dental caries and may proliferate under acidic conditions. This study aimed to investigate the association between dental caries indices and oral levels of cariogenic microorganisms in children with GERD symptoms compared with healthy controls. Methods This case-control study included 32 children with GERD symptoms and 37 healthy children aged 5–11 years. GERD symptoms were assessed using the Gastroesophageal Reflux Disease Assessment in Pediatrics Questionnaire (GASP-Q). Dental status was evaluated using the decayed, missing, and filled teeth (dmft/DMFT) index according to WHO criteria. Oral microbial samples were collected from the tongue and buccal mucosa using sterile cotton swabs, and the levels of S. mutans and S. sobrinus were quantified using culture-based methods. Statistical analyses were performed using chi-square tests, independent t-tests, Pearson correlation coefficients, and linear regression analysis at a significance level of P < 0.05. Results The mean age of participants was 8.22 ± 1.92 years. No significant differences were observed between the GERD and control groups regarding age (P = 0.379), sex distribution (P = 0.126), or dmft/DMFT scores (P = 0.410). However, the mean bacterial count was significantly higher in children with GERD symptoms compared with healthy controls (P < 0.001). After adjustment for age, sex, and dmft + DMFT, multivariable linear regression analysis indicated that children in the case group tended to have higher log 10 bacterial counts than those in the control group, although the association was not statistically significant (β = 1.009, 95% CI: −0.192 to 2.209, P = 0.098). Conclusion Athough children with GERD showed higher salivary counts of Streptococcus mutans and Streptococcus sobrinus, this association was not significant after adjustment for confounding factors. GERD was not independently associated with cariogenic bacterial counts or dental caries experience.