Hyperdivergency and lip posture in relation to self-reported sleepiness in adolescents

PURPOSE: To examine associations between vertical craniofacial growth pattern, self-reported daytime sleepiness, sleep-related complaints, and lip posture in adolescents. METHODS: This cross-sectional study included 157 adolescents aged 12-14 years classified as hyperdivergent (n = 121) or normodivergent (n = 36). Daytime sleepiness and sleep-related complaints were assessed using an Epworth sleepiness scale (ESS)-based questionnaire and Berlin questionnaire (BQ)-derived items. Lip posture was measured cephalometrically. Independent t‑tests, chi-square/Fisher exact tests, Pearson correlations, and multiple linear regression were used. RESULTS: Hyperdivergent adolescents had higher ESS and BQ scores (p < 0.001; ESS d = 0.70), more frequent sleep-disordered breathing (SDB)-related symptoms (p < 0.05), and a significant Frankfort mandibular plane angle (FMA)-ESS association after adjustment for age, body mass index, and sex (β =0.354, p < 0.001). Lip posture showed no group differences or associations with BQ, with only weak correlations with ESS or sleep duration. CONCLUSION: Hyperdivergence, but not lip posture, was associated with greater questionnaire-derived sleepiness and SDB symptoms.