Craniofacial dimensions and malocclusions in children and adolescents with a high body mass index: a systematic review and meta-analysis.

Background: Obesity and overweight represent significant public health concerns affecting children and adolescents. Besides their association with accelerated pubertal growth, the high body mass index (BMI) has been implicated in craniofacial dimension alterations and malocclusion development within this age group.

Objective: This study aimed to evaluate the impact of high BMI on sagittal and vertical craniofacial dimensions and malocclusions in children and adolescents. Search methods: We conducted unrestricted electronic searches across nine databases until November 2024. Selection criteria: Inclusion criteria were cross-sectional, case-control, and cohort studies involving participants aged 5 to 19 years that established a relationship between BMI, dimensional changes in craniofacial structures, and the presence of malocclusion. The research question applied the PECO framework. Data collection and analysis: After removing duplicates, extracting the data, and assessing the risk of bias with the JBI Critical Appraisal Tools for observational studies, we performed random-effects meta-analyzes of mean differences (MD) with 95% confidence intervals (CI). Subsequently, we assessed the quality of evidence.

Results: The study included 21 articles (19 cross-sectional, one cohort, one case-control) with low-to-moderate risk of bias. Eight studies focused on craniofacial dimensions, and 13 on malocclusion. The meta-analysis revealed significantly larger sagittal dimensions in patients with obesity or overweight, including extended cranial base length (S-N, MD = 0.8452 [0.5531-1.1373]), mandibular length (Cd-Gn, MD = 0.5770 [0.0639-1.0902]), maxillary length (Cd-A, MD = 0.8021 [0.4251-1.1790]), and bimaxillary protrusion (SNA, MD = 0.6008 [0.1099-1.0916]; SNB, MD = 0.6712 [0.1328-1.2096]; SNPg, MD = 0.5921 [0.0666-1.1175]). Concurrent gains in posterior facial height (S-Go, MD = 0.6619 [0.2385; 1.0853]) in the vertical dimension usually did not alter the overall facial plane, tending towards more horizontal growth. These gains were higher for girls with high BMI. Regarding malocclusions, only two of the 13 studies identified statistically significant associations between dental crowding and high BMI. While seven studies exhibited a low risk of bias, the included articles commonly demonstrated limited control over potential confounders.

Conclusion: Based on limited evidence, children and adolescents with high BMI presented enhanced bimaxillary prognathism and enlarged sagittal and vertical craniofacial dimensions. The BMI did not consistently impact malocclusions, although a few studies linked dental crowding to overweight. Orthodontic planning for this population should consider the patient's BMI.

Registration: PROSPERO (CRD 42024511194).