# Dentomaxillofacial abnormalities associated with rare bone disease in two pediatric populations from southern Europe and East Africa

## TL;DR

This study compares dentomaxillofacial issues in children with rare bone diseases from East Africa and southern Europe, finding differences in dental health and malocclusion rates.

## Contribution

The study provides a comparative analysis of DOMF abnormalities in two distinct geographic populations with rare bone diseases.

## Key findings

- East African children showed higher rates of gingivitis, dental fluorosis, and malocclusion compared to southern European children.
- Dental agenesis was significantly more prevalent in the East African group.
- Pathological fractures were more frequent in the DGD subgroup in both populations.

## Abstract

It is well known that certain bone diseases of congenital origin are associated with dentomaxillofacial (DOMF) disorders. The objective of this study was to evaluate and compare the DOMF alterations in pediatric patients with bone diseases in Arusha (Tanzania, East Africa) and Barcelona (Spain, southern Europe). In each area of study, the clinical differences between subgroups of bone diseases in relation to their etiopathogenesis were reported and analysed.

A cross-sectional study of pediatric patients with bone diseases was carried out at two hospitals, Mount Meru Regional Referral Hospital (MMRRH), Arusha (n = 60) and Hospital Sant Joan de Déu (HSJD), Barcelona (n = 89), from 2019 to 2023. Mean age of the sample was 10.5 years (SD 4.05). In both groups the samples were recruited consecutively and were clinically evaluated for skeletal and DOMF disorders. The different bone pathologies were further divided into two subgroups according to their etiopathogenesis: (i) disorders in cellular metabolism (DCM); (ii) disorders of bone growth/deformity (DGD).

Gingival health indexes were significantly better in the HSJD group (p = 0.033). The HSJD group also had better caries indices (DMF-T), though these differences were not significant (p = 0.105). Among dental alterations, dental agenesis was significantly more prevalent in the MMRRH sample (p < 0.001); in this sample, DGD was significantly more frequent than DCM (p = 0.045). Fluorosis was practically non-existent in the HSJD group, but was moderate to severe fluorosis in 26.6% of MMRRH patients and was significantly more prevalent in the MMRRH DCM subgroup (p < 0.001). Malocclusion was more frequent in the MMRRH group (p < 0.001 in the case of Class III inverted overjet and p = 0.008 in the case of crossbite), and in the HSJD group the DCM subgroup presented a more severe overbite and open bite than the DGD subgroup (p = 0.027). Pathological fractures were significantly more frequent in the DGD subgroups in both samples (p < 0.001).

There is a clear relationship between dentomaxillofacial abnormalities and rare bone diseases in the two pediatric populations studied. Comparing the two samples, the East African children displayed higher rates of gingivitis, dental fluorosis and malocclusion than their southern European peers.