Autism spectrum disorder and the risk of supernumerary teeth: A multi-centre cohort study

Aim: To assess whether children diagnosed with autism spectrum disorder (ASD) are at risk of having supernumerary teeth (SNT). Methods: This was a multi-centre cohort study conducted between 2008 and 2022 to recruit children under 18 years of age who were previously diagnosed with ASD. Data on age, sex, and comorbidities history were collected and adjusted in the analyses. Cox proportional hazard models and Kaplan-Meier analyses were conducted to determine the effect of ASD on SNT. Subgroup analyses based on age and sex stratification were developed to identify at-risk subpopulations. Results: A total of 3,372 cases with ASD and 25,942 controls were included. 15 children with ASD and 31 non-ASD children were diagnosed with SNT during the follow-up period. The incidence of SNT was significantly higher in the ASD group compared to the non-ASD group (1.827 vs 0.671 per 1000 person-years, adjusted hazard ratio, aHR=2.583, 95% CI=1.312-5.085). Male children with ASD (aHR=3.863, 95% CI=1.781-8.376) and children with ASD aged below 6 years (aHR= 2.655, 95% CI=1.117-6.308) presented with significant risk of having SNT. Conclusions: Male children with ASD are at a significant risk of SNT. Screening for children with ASD may facilitate early detection and management of ASD-associated SNT.