Аңдатпа
A bstract Aim: The prevalence of autism spectrum disorder (ASD) and early childhood caries (ECC) is increasing globally. The association between ASD and ECC remains unclear. This study aimed to evaluate risk factors for ECC in children with ASD in Kazakhstan and Ukraine. Materials and Methods: This multi-center observational study included 190 children aged 5–6 years (125 with ASD and 65 without ASD) from Kazakhstan ( n = 98) and Ukraine ( n = 92). Data on oral hygiene practices, dietary habits, and oral fluid pH were collected through parental surveys and clinical examinations. Oral hygiene was assessed using a modified plaque index (Kazakhstan) and the Fedorov–Volodkina index (Ukraine). Statistical analysis included the average values of quantitative data, and the Student t test was calculated. Mixed-effects analysis of variance was used for intergroup and intragroup comparison of the results of the quality of hygiene in children 5–6 years. Results: In Kazakhstan, only 16.07% of children with ASD brushed their teeth twice daily, compared to 33.33% in Ukraine. Mean plaque index scores indicated poor oral hygiene in children with ASD in both Kazakhstan (2.6 ± 0.14) and Ukraine (2.70 ± 0.13). Oral fluid pH was significantly lower (more acidic) in children with ASD in both Kazakhstan (5.53 ± 0.07) and Ukraine (5.96 ± 0.07) compared with controls. The dietary habits observed slow eating patterns in the ASD group from the range of 8.70–25%. Conclusions: Children with ASD in both Kazakhstan and Ukraine exhibit a higher risk for ECC, which is associated with poor oral hygiene practices and acidic oral pH. These findings highlight the need for targeted oral health interventions and guidelines for children with ASD, irrespective of geographic location.