Skeletal and Dentoalveolar Features in Patients with Deep Overbite Malocclusion

OBJECTIVE An increased overbite may be due to a skeletal or dental etiology that may influence treatment. The purpose of this study was to evaluate the skeletal and dentoalveolar features in patients with deep bite malocclusion in an Iranian population and to determine the most and least effective and contributory variables causing deep bite. MATERIALS AND METHODS Lateral cephalograms and study casts of normal (n=85) and deep bite (n=85) subjects were used to evaluate skeletal and dentoalveolar variables. Data were analyzed statistically by independent t-test. The percentages of each variable within normal limits, less and more than one standard deviation were calculated for deep bite subjects. RESULTS The most significant skeletal contributing factors were gonial and basal angles, as well as the posterior facial height, ramus length, lower anterior facial height and upper anterior facial height. An increased curve of spee and decreased mandibular first molar height were predominant dental variables in the deep bite group. The variables with the greatest variances from the normal limit were the ratio of the lower anterior facial height to the total anterior facial height, the lower anterior facial height to the upper anterior facial height and the ramus length. CONCLUSION The counterclockwise rotation of the mandible and the increased curve of spee were the dominant feature of deep bite malocclusion.