Intestinal parasitic infections and their association with bruxism, tooth wear, and temporomandibular disorders in children in rural Egypt: a cross-sectional study

Background Bruxism is a common oral habit characterized by involuntary grinding of teeth, traditionally linked to multiple factors, including intestinal parasitic infections (IPIs). This study investigated the association between bruxism, as measured by tooth wear and temporomandibular disorders (TMDs), and the presence of IPIs in children. Methods A comparative cross-sectional study was conducted at a governmental primary health unit in Alexandria, Egypt, between August 2023 to 2024. A convenience sample of 450 healthy children (aged 3–10 years), with Angle’s Class I occlusion, were recruited and their infection status was confirmed based on their stool analysis results (positive for IPIs, n = 225; negative for IPIs, n = 225). Parents completed a questionnaire on demographics and bruxism risk indicators. Bruxism was evaluated using parent reports, the Helkimo’s clinical Dysfunction Index for TMDs and masticatory muscle assessment, and the Hugoson’s Tooth Wear Index for dental wear. Descriptive statistics and multivariable logistic regression models were used for data analysis. Results Of the 450 children, 50.6% were females. The mean age was significantly higher (7.38 ± 1.94) in the positive group than in the negative group (6.71 ± 1.52). Reported bruxism was significantly more frequent in participants with IPIs (61.5%, p = 0.001). Mild TMD was significantly more prevalent in children with IPIs (+ ve = 60.1%, p = 0.001). The mean number of affected teeth with wear was (2.72 ± 3.29) in the positive group and (2.50 ± 3.41) in the negative group. IPIs were significantly associated with bruxism (AOR = 2.08; 95% CI: 1.32–3.29; tooth wear (AOR = 1.64; 95% CI: 1.08–2.47), and TMD (AOR = 1.85; 95% CI: 1 0.23–2.80). Conclusion Children with IPIs showed a higher occurrence of bruxism as reported by their mothers, which was associated with mild temporomandibular disorders (TMDs) and increased tooth wear.