Virginia Commonwealth University VCU Scholars Compass Theses and Dissertations Graduate School 2007 Overbite Correction and Smile Esthetics Kevin Erick Kelleher Virginia Commonwealth University Follow this and additional works at: https://scholarscompass.vcu.edu/etd Part of the Orthodontics and Orthodontology Commons © The Author Downloaded from https://scholarscompass.vcu.edu/etd/1265 This Thesis is brought to you for free and open access by the Graduate School at VCU Scholars Compass. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of VCU Scholars Compass. For more information, please contact [email protected]. © Kevin E. Kelleher, 2007 All Rights Reserved OVERBITE CORRECTION AND SMILE ESTHETICS A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University. by KEVIN E. KELLEHER B.A., State University of New York at Buffalo, 2000 D.M.D., Medical University of South Carolina, 2005 Director: Steven J. Lindauer D.M.D., M.D.Sc. Chairman of the Department of Orthodontics Virginia Commonwealth University Richmond, Virginia June 2007 ii Acknowledgement I would like to thank my family for their support, patience, and encouragement. I am also very thankful to Dr. Steven Lindauer, Dr. Bhavna Shroff, and Dr. Eser Tüfekçi for their guidance over the last two years and to Dr. Shannon Lewis and Dr. Sheriff Elhady for their previous work on this study. My gratitude is also extended to my co-residents for their help recruiting patients. iii Table of Contents Page Acknowledgements............................................................................................................. ii List of Tables .......................................................................................................................v List of Figures.................................................................................................................... vi Abstract………...……………………………………………………………………….. vii Introduction..........................................................................................................................1 Materials and Methods.........................................................................................................7 Overview .......................................................................................................7 Intra-Examiner Reliability for Cephalometric Measurments........................8 Intra- and Inter-Examiner Reliability Smile Arc Assessment.......................8 Subjects and Measurements ..........................................................................8 Statistics.......................................................................................................10 Results................................................................................................................................13 Intra-Examiner Reliability for Cephalometric Measurments......................13 Smile Arc Assessment.................................................................................13 Characteristics of Treated Groups...............................................................13 Clinical and Cephalometric Measurements.................................................14 Smile Arc Assessment.................................................................................25 Discussion..........................................................................................................................27 Conclusions........................................................................................................................32 iv References..........................................................................................................................33 Appendices.........................................................................................................................37 Appendix A – Intrusion Arch Group ...............................................................37 Appendix B – Bite Plate Group .......................................................................39 Vita ......................................................................................................................................41 v List of Tables Page Table 1: Description of cephalometric measurements.......................................................12 Table 2: Characteristics of treated groups .........................................................................14 Table 3: Mean values (SD) for the intrusion arch group. ..................................................15 Table 4: Mean values (SD) for the bite plate group...........................................................15 Table 5: Comparison of mean values (SD) between groups..............................................16 Table 6: Comparison of mean changes (SD) between groups...........................................16 Table 7: Smile arc assessments .........................................................................................26 vi List of Figures and Appendices Page Figure 1: Cephalometric landmarks...................................................................................11 Figure 2: Mean value and 95% confidence intervals for overbite correction....................17 Figure 3: Mean values and 95% confidence intervals for lip-to-tooth ..............................18 Figure 4: Mean values and 95% confidence intervals for OP-U1IE .................................19 Figure 5: Mean values and 95% confidence intervals for OP-U1CR................................20 Figure 6: Mean values and 95% confidence intervals for SN-U1 .....................................21 Figure 7: Mean values and 95% confidence intervals for MP-L1.....................................22 Figure 8: Mean values and 95% confidence intervals for OP-L1CR ................................23 Figure 9: Mean values and 95% confidence intervals for SN-MP ....................................24 Appendix A Intrusion Arch Group ....................................................................................37 Appendix B Bite Plate Group ............................................................................................39 vii Abstract OVERBITE CORRECTION AND SMILE ESTHETICS Kevin E. Kelleher, D.M.D. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. Virginia Commonwealth University, 2007 Thesis Director: Steven J. Lindauer DMD, M.D. Sc. Department of Orthodontics, Chairman and Program Director The purpose of this prospective clinical study was to investigate differences in outcomes from two common treatment modalities used to reduce deep overbite: maxillary incisor intrusion using an intrusion arch and posterior tooth eruption using an anterior bite plate. Pre-treatment, post-overbite correction and post-treatment records were gathered from 32 patients who presented with deep overbite malocclusions to the Virginia Commonwealth University orthodontic clinic. Both groups of patients experienced reductions in overbite and maxillary incisor display as well as maxillary and mandibular incisor proclination and mandibular incisor occlusal movement during treatment. In the intrusion arch group, the center of resistance of the maxillary incisor was significantly intruded during overbite correction. The maxillary incisor incisal edge was significantly more intruded at the end of treatment in the viii intrusion arch group. Both groups experienced flattening of the smile arc in agreement with previous studies showing similar changes in orthodontically treated individuals. Introduction One of the primary goals of orthodontics is to establish occlusal harmony between the maxillary and mandibular dentition while maintaining or enhancing facial esthetics.1 The desire for improved facial appearance is a motivating factor for patients seeking orthodontic treatment. Physical attractiveness is highly valued in most cultures and an attractive smile is considered to be one of the most important attributes of facial esthetics.2 Esthetic considerations in the selection of orthodontic treatment goals have become increasingly important to orthodontists.3 Attempts have been made to define and quantify the smile characteristics that are considered to be ideal. Defining these characteristics has helped practitioners to establish individualized treatment goals based on achieving ideal smile architecture. Vertical positioning of the upper incisors and configuration of the smile arc are two significant factors that have been found to influence smile attractiveness. Some suggestions have been made regarding treatment strategies that should be used to maintain or produce ideal smile esthetics, but no evidence has been presented to substantiate these approaches. In the later part of the 19th century, Kinglsey4 emphasized the esthetic objectives of orthodontic treatment. In his view the articulation of the teeth was secondary to facial appearance. Early in the 20th century, Case5 continued to advocate the paramount importance of esthetics in orthodontic treatment planning. Angle,6 however, believed 1 2 that if the teeth were put in proper occlusion then optimal facial esthetics would be produced. With the influence of Angle’s teachings on occlusion and with the advances in orthodontic technology, especially radiographic cephalometry, orthodontists became increasingly focused on hard tissue goals. Burstone7