Date of Award
Summer 2023
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Del Santo, Marinho
Second Advisor
Liu, Dawei
Third Advisor
Mehta, Shivam
Abstract
Objective : Class II malocclusion has been extensively studied, however there are many unanswered questions. This study analyzed the difference in incisor and molar dentoalveolar heights of untreated subjects presenting with Class I and Class II malocclusion. Dentialveolar heights are an aspect of the craniofacial complex that changes with growth and development and are manipulated by orthodontists. These changes hold important clinical implications for the development, maintenance and treatment of malocclusions. Methods : A sample of 96 untreated Class I and Class II subjects, with a total of 611 cephalograms was drawn from the archives of the University of Michigan Growth Study. A total of 26 Class II patients and 70 Class I patients, aged 7-17. All cephalograms were traced in 150 dpi size (converted by the software GIMP), 151 landmarks were identified via Viewbox. The identification of 10 main landmarks allowed 7 linear measurements for analysis. Data was collected and analyzed in SPSS utilizing an unpaired t-test for each variable, with equal variances assumed ,as well as method error for landmarks according to the Dahlberg formula. Results : Statistical comparisons showed there were no significant differences (p< 0.05) between Class I and Class II for each variable. According to Dahlberg formula, error varied from 0.22 for L1 Tip to 1.62 of L6 mesial cusp. Conclusion : The null hypothesis is accepted. Under these circumstances, there is no difference between Class I and Class II subjects in dental alveolar heights.