Relationships Between the Tonsillar Hypertrophy and Nocturnal Labial Incompetence in Children with Malocclusion

Background : This study aimed to investigate the relationships between the tonsillar hypertrophy and nocturnal labial incompetence (NLI) in children with malocclusion. The findings are intended to inform early orthodontic or medical intervention strategies for children presenting with both tonsil hypertrophy and malocclusion. Methods : A retrospective study was conducted using initial consultation records, lateral cephalograms, online questionnaires, and telephone follow-ups. Tonsil hypertrophy was evaluated in the transverse dimension using Brodsky’s classification and in the anteroposterior dimension using the Baroni method on lateral cephalograms. Children were categorized into a hypertrophic tonsils group (Brodsky grade >2 or sagittal airway obstruction ≥50%) and a non-hypertrophic control group (Brodsky grade ≤2 and obstruction <50%). The prevalence of NLI was assessed with initial consultation records. Intergroup differences were analyzed using the Bonferroni-adjusted χ² test (α = 0.017). Results : A total of 190 children were included, with 68.9% in the hypertrophic group and 31.1% in the non-hypertrophic group. The overall prevalence of NLI was 82.6%, significantly higher in the hypertrophic group (96.2%) compared to the control group (52.6%, χ² = 53.98, P < 0.001). Among children with NLI, the overall improvement rate was 51.6%, with a significantly higher rate observed in those who underwent tonsillectomy (80.7%) than in those who did not (14.5%, χ² = 67.84, P < 0.001). Conclusions : Tonsil hypertrophy is significantly associated with increased prevalence of NLI in children. Tonsillectomy may substantially improve NLI symptoms, suggesting a potential therapeutic benefit in affected patients.