# Macro- and microstructural assessment of alveolar bone in adults with different vertical facial patterns using cone beam computed tomography

## TL;DR

This study uses cone beam CT to compare alveolar bone structure in adults with different vertical facial patterns, finding gender-specific differences in bone thickness and microstructure.

## Contribution

The study provides new insights into macro- and microstructural alveolar bone differences in hyperdivergent and normodivergent facial patterns with gender-specific variations.

## Key findings

- Hyperdivergent males have thicker inter-radicular thickness in posterior maxilla and mandible with increased trabecular separation.
- Hyperdivergent females show thinner inter-radicular thickness in anterior regions and lower bone volume between lateral incisors and canines.
- Normodivergent individuals show minimal gender differences, while hyperdivergent individuals show pronounced site-specific variations.

## Abstract

Vertical facial growth patterns play a crucial role in craniofacial morphology and have significant implications for diagnosis, treatment planning, and long-term stability in orthodontics and maxillofacial surgery. This study sought to comprehensively study the macro- and microstructure of alveolar bone in different vertical facial patterns using cone beam computed tomography (CBCT).

A cross-sectional study involved 120 CBCT scans divided equally into normodivergent and hyperdivergent vertical facial patterns of both genders. Alveolar bone analyses were conducted for both the maxilla and mandible from central incisors to 2nd molars. Inter-radicular thickness (IRT) measurements were performed at 4 different vertical levels (4, 6, 8 and 11 mm). For the microstructural analysis, the extracted file of area of interest was obtained, and then ImageJ was used to assess trabecular bone thickness (Tb.Th), separation (Tb.SP), bone volume ratio (BV), and fractal dimension (FD). The independent t-test was used to assess the differences across all groups.

Hyperdivergent males exhibited statistically significant thicker IRT, particularly in the posterior maxilla and mandible, with increased Tb.SP, and lower BV in most sites compared to normodivergent facial pattern. In contrast, hyperdivergent females had significantly thinner IRT, specifically in the anterior maxilla and mandible, associated with lower BV (notably between the lateral incisors and canines). Normodivergent males and females showed minimal differences, while the hyperdivergent group demonstrated more pronounced gender-related variation in both macrostructural and microstructural alveolar bone characteristics at different sites.

Hyperdivergent individuals exhibit distinct site- and gender-specific differences at the macrostructural level, accompanied by microarchitectural adaptations across both maxilla and mandible in comparison to normodivergent individuals.