Association between adenotonsillar hypertrophy and dentofacial characteristics of children seeking for orthodontic treatment: A cross-sectional study

To compare the dentofacial characteristics of children with and without adenoid and/or tonsillar hypertrophy. A consecutive sample of orthodontic patients aged 6-12 that took pre-treatment lateral cephalograms were included in this study. Those with history of previous orthodontic treatment, adenoidectomy or tonsillectomy, or craniofacial anomalies were excluded. The diagnosis of adenoid and tonsillar hypertrophy was based on Fujioka's and Baroni's methods, according to which the subjects were divided into four groups: the adenoid hypertrophy only (AHO) group; tonsillar hypertrophy only (THO) group; combined adenoid and tonsillar hypertrophy (AH+TH) group; and no adenoid or tonsillar hypertrophy (NH) group. Cephalograms were used for skeletal and dental measurement. Data were analyzed using one-way ANOVA, LSD post-hoc tests and Chi-square test. A total of 598 patients were included. Compared with the NH group, the THO group had significantly larger SNB angle (P<0.001), as well as significantly smaller ANB angle (P<0.001) and Wits value (P=0.001). The U1-L1 angle of AHO group was significantly smaller than that in the NH group (P=0.035). The proportion of adenoid hypertrophy in Class II patients was significantly higher than that in Class III patients (P=0.001). The proportion of tonsillar hypertrophy in Class III patients was significantly higher than that in Class I patients (P<0.001) and Class II patients (P<0.001). Over 80% of children seeking orthodontic treatment had either adenoid or tonsillar hypertrophy. Children with adenoid hypertrophy tend to have skeletal Class II malocclusion, while those with tonsillar hypertrophy tend to have skeletal Class III malocclusion.