Brent Leggett


Introduction: The purposes of this study were to determine the prevalence of Class II (Cl II) subdivision patients, to quantify the change in TMJ complex, and mandibular length after treatment was accomplished. Materials and Methods: Records of consecutive patients who sought orthodontic treatment at Loma Linda University (LLU) were screened. Only patients with dental Cl II subdivision that had completed treatment with pre- (T1) and post-treatment (T2) cone beam computed tomograms (CBCTs) available were evaluated for changes in the TMJ complex position related to Foramen Rotundum (TMJ-FR), joint spaces and mandibular length (condylion to genial tubercles). Comparisons were made between T1 and T2 as well as Class I (Cl I) and Cl II sides using a related samples Wilcoxon signed rank test at α = 0.05. Results: There were 2130 patients seen at LLU between 2008-2015. Four hundred and seventy one (22%) were diagnosed with Cl II malocclusions and 104 (5%) were Cl II subdivision. Thirty-six (10 male and 26 female) patients with a mean age of 17.5 (range = 10.4-64.25) years had complete records and were included in this retrospective study. When comparing the Cl I and Cl II sides, only mandibular length at T1 was significantly different (p = .023). Mandibular lengths at T2 were also significantly longer than at T1 for both Cl I (3.18 mm; p = <.001) and Cl II (3.26 mm; p < .001) sides. Fourteen of 48 FR-TMJ, and 1 of 6 joint space comparisons between T1 and T2 measurements were statistically significantly different (p < .05) but only ranged from 0.36-1.31 mm. Conclusions: Within the confines of this study, Class II subdivision condition and treatment do not seem to be of any clinical consequence to the TMJ complex position and joint space. The change in mandibular length observed in this study was likely attributed to normal growth.

LLU Discipline

Orthodontics and Dentofacial Orthopedics


Orthodontics and Dentofacial Orthopedics


School of Dentistry

First Advisor

Caruso, Joseph M

Second Advisor

Olson, Gregory

Third Advisor

Rungcharassaeng, Kitichai

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Malocclusion - Angle Class II -- pathology; Orthodontics - Corrective; Cone-Beam Computed Tomography; Temporomandibular Joint

Subject - Local

Foramen Rotundum; Mandibular Condyle; Mandibular Length



Page Count


Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website


Loma Linda University. Del E. Webb Memorial Library. University Archives