Tomographic Study of the Greatest Height, Thickness, and Density of the Infrazygomatic Crest for the Insertion of Extra-Alveolar Miniscrews

Aim: To assess the height, thickness, and density of the infrazygomatic crest for extra-alveolar miniscrew insertion using cone beam computed tomography (CBCT). Methods: Retrospective data from 65 CBCTs of Peruvian adults aged 20 to 38 years (mean age 27.37 years) with complete maxillary dentition were used in this study. Height (mm), thickness (mm), and density (Misch classification) were measured in the left hemimaxilla at the mesial and distal level of the upper first molar and the mesial of the second molar. Data on age and sex were collected. Intergroup comparisons were analyzed using the ANOVA or Kruskal-Wallis test. Results: The heights from lowest to highest values were mesial second molar (10.39 ± 2.01 mm) < distal first molar (13.24 ± 1.44 mm) < mesial first molar (15.95 ± 2.06 mm) (P < 0.001). The thickness was statistically greater in the mesial second molar (5.5 mm) than in the first molar (3.4 to 3.42 mm) (P < 0.001). Density was similarly distributed between type 1 (50.8 to 56.9%) and 2 (43.1 to 49.2%) at the three levels of molar roots (P > 0.05). Age and sex were not found to be statistically related to infrazygomatic crest height, thickness, or density at the three molar root levels (P > 0.05). Conclusion: Both the first and second molar infrazygomatic crest had adequate bone quality for extra-alveolar miniscrews placement, but the mesial of the second molar had the greatest thickness and a shorter distance from the occlusal plane, regardless of age and sex.