Screen time and bruxism in children and adolescents: evidence remains unclear

This systematic review, registered in PROSPERO, screened five databases through September 2025 and included 13 studies (11 cross-sectional designs and 2 cohort studies) that examined the relationship between screen time or screen device use and bruxism in participants aged 0–18 years. The studies used various detection methods (clinical examination, parental report, questionnaires) and examined awake bruxism, sleep bruxism, or unspecified bruxism. Eight studies reported a statistically significant association between screen use and bruxism, particularly when evaluating longer daily screen durations (e.g., ≥2–3 hours daily) or indicators of problematic digital use. However, five studies found no significant association. The GRADE tool assessment found the overall certainty of evidence to be very low, meaning confidence in the results is limited. The heterogeneity in study designs, bruxism detection methods, and definitions of screen time made firm conclusions impossible. The authors conclude that a causal or even consistent associative link between screen use and bruxism cannot yet be established, and well-designed longitudinal studies with standardized measures are needed.

The disparity between positive and null findings reflects deeper methodological challenges: most included studies were cross-sectional, which cannot establish temporal relationships or rule out reverse causality (e.g., children with bruxism seeking screen distraction). Studies that specifically evaluated 'problematic' digital use or very high daily screen hours (typically ≥3 hours) were more likely to report associations, suggesting a potential threshold or behavioral-use intensity effect rather than mere exposure. Notably, several studies relied on parental observation or self-report for bruxism detection, which is prone to underdetection of sleep bruxism and misclassification of awake habits. The authors emphasize that confounders—stress, anxiety, sleep quality, caffeine intake, and genetic predisposition—were either unmeasured or incompletely reported across studies, making it impossible to know whether screen use itself drives bruxism or whether both are markers of underlying stress or poor sleep hygiene. This review underscores a pattern common in child digital health research: a small number of early, methodologically weak studies create apparent 'association,' but replication and stronger designs often do not confirm it.