Is adenotonsillar hypertrophy associated with dentofacial morphology? A systematic review and meta-analyses

As a common cause of upper airway obstruction in children, adenotonsillar hypertrophy (ATH) has been hypothesized to adversely affect dentofacial development and morphology. This systematic review aimed to summarize the existing evidence regarding the association between ATH and dentofacial characteristics of children.

Four databases (PubMed, Embase, Web of Science, and VIP Chinese Journal Database) were searched from inception to November 1, 2024, for cross-sectional studies that compared the dental or craniofacial characteristics of children with and without adenoid hypertrophy (AH) and/or tonsillar hypertrophy (TH). The Newcastle-Ottawa Scale for Cross-Sectional Studies was used to assess the methodologic quality of included studies. Meta-analyses were performed with the random-effects model.

Thirty-six studies were included in this review. According to meta-analyses, the mandibular plane angle (SN-MP: mean difference [MD] = 2.20° [95% confidence interval {CI} 1.47-2.92]; P <0.00001), articular angle (ArGoMe: MD, 1.23° [95% CI, 0.68-1.79]; P <0.0001) were significantly greater in children with AH and/or TH. No significant differences were found between the ANB angle between the 2 groups (MD, 0.31° [95% CI, -0.35 to 0.61]; P = 0.59). However, the SNA (MD, -0.30° [95% CI, -0.53 to -0.06]; P = 0.01) and SNB angle (MD, -0.78° [95% CI, -1.33 to -0.24]; P = 0.005) were found to be significantly smaller in children with AH and/or TH. Regarding dental characteristics, the rate of Angle Class II and III malocclusions (relative risk = 1.29 [95% CI, 1.14-1.45]; P <0.0001) and open bite (relative risk = 1.65 [95% CI, 1.21-2.25]; P = 0.001) were found to be higher in the AH and/or TH children. In addition, the width between the maxillary first molars (MD, -1.34 mm [95% CI, -2.12 to -0.56]; P = 0.0008) was found to be smaller both in AH and TH children.

On the basis of evidence of low to very low certainty, children with ATH tend to exhibit craniofacial characteristics such as sagittal maxillary and mandibular retrognathia and an increased mandibular plane angle. In addition, children with ATH children appear to have a higher prevalence of Class II and III malocclusions, open bite, and a narrower maxillary arch width compared with their non-ATH counterparts. However, these findings must be interpreted with caution because of the limited quality and consistency of the available evidence. The statistically significant differences identified in this review are relatively small when compared with population deviations, raising questions about their clinical significance. Further high-quality studies with standardized methodologies are needed to confirm these associations and clarify their clinical relevance.