Comparative Evaluation of Bone Thickness and Insertion Heights in the Infrazygomatic Crest Region Across Different Facial Patterns: A Cone Beam Computed Tomography Study

Objective This study aimed to assess the infrazygomatic crest (IZC) bone thickness and insertion heights at varying insertion angles in patients with different vertical facial growth patterns using cone beam computed tomography (CBCT). Materials and Methods The study included 48 healthy Maharashtrian Indian subjects (24 males, 24 females; aged 20-30 years) with no history of previous orthodontic treatment. Subjects were classified into three groups—hypodivergent, normodivergent, and hyperdivergent based on cephalometric parameters (Sella–Nasion to mandibular plane angle, overbite depth indicator, Jarabak’s ratio). CBCT imaging (Carestream CS 9300) was used to assess IZC bone thickness and insertion heights at insertion angles from 40° to 80°. The measurements were taken bilaterally, and data were analyzed for group-wise, gender-wise, and side-wise differences using analysis of variance and Scheffé’s post hoc test. Results Bone thickness increased progressively with an increase in insertion angles across all the groups. Hypodivergent subjects exhibited the highest bone thickness, followed by normodivergent, with hyperdivergent showing the least. Males and the left side measurements showed higher bone thickness generally. Insertion heights decreased with increasing angles across all the groups, with hyperdivergent subjects having the highest heights. No consistent gender- or side-based variations in insertion heights were observed. Conclusions IZC bone morphology varies significantly with vertical facial growth patterns. Hypodivergent individuals exhibited greater cortical bone thickness, whereas hyperdivergent individuals demonstrated greater insertion heights. Bone thickness increased, and insertion height decreased with increasing insertion angulation.