Age-related hypertrophy of adenoid and tonsil with its relationship with craniofacial morphology

BACKGROUND: When analyzing the relationship between adenotonsillar hypertrophy and craniofacial morphology, researchers generally regarded hypertrophied adenoids and tonsils as a whole. It remains unclear whether different enlarged sites of pharyngeal lymphoid tissue would correlate with multiple craniofacial subtypes. We hypothesized there would be craniofacial subtypes correlated with different locations of hypertrophied adenoid and tonsil. METHODS: Lateral cephalometric radiographs were obtained from 466 children (171 boys and 295 girls, aged 12.27 ± 2.69 years). They were divided into four groups according to different sites of enlarged pharyngeal lymphoid tissue: adenoid hypertrophy group (AG, n = 126), tonsillar hypertrophy group (TG, n = 59), adenotonsillar hypertrophy group (ATG, n = 69) and control group (CG, n = 212). Five commonly used angles for cephalometric measurements were investigated: SNA (Sella-Nasion-Point A), SNB (Sella-Nasion-Point B), ANB (Point A-Nasion-Point B), mandibular plane angle (MP/SN) and Y-axis angle (SGn/FH). RESULTS: Children with isolated tonsillar hypertrophy correlated with increased SNA (unstandardized regression coefficient B = 1.38, p = 0.009) and SNB (B = 1.99, p = 0.001) compared with controls. However, children with isolated adenoid hypertrophy correlated with decreased SNB (B=-0.94, p = 0.036), increased ANB (B = 0.74, p = 0.014) and increased MP/SN (B = 2.22, p < 0.001). Similarly, children with adenotonsillar hypertrophy correlated with decreased SNB (B=-1.36, p = 0.015), increased ANB (B = 1.35, p < 0.001) and increased MP/SN (B = 2.64, p = 0.001). CONCLUSIONS: Isolated adenoid hypertrophy correlated with a retrognathic mandible, an increased maxillo-mandibular sagittal discrepancy, and an increased mandibular plane angle. Isolated tonsillar hypertrophy correlated with maxillary and mandibular protrusion. Adenotonsillar hypertrophy did not show a superimposed craniofacial pattern of the above two but showed the same craniofacial pattern as isolated adenoid hypertrophy.