Predominant dental and skeletal components associated with open-bite malocclusion

Abstract

BackgroundVarious dentoskeletal factors can contribute to open-bite manifestation. This study aimed to compare dental and skeletal features in Iranian subjects with open bite and normal over bite and to determine the most frequent dental and skeletal contributing factors associated with open-bite malocclusion. MethodsIn this cross-sectional study, dental and skeletal measurements were made on pretreatment lateral cephalograms and study models of the two groups, 80 patients with open-bite manifestation and 80 individuals with normal over bite. The subjects in both groups were aged 12 to 35 years. Data were subjected to t test using SPSS. ResultsOur findings showed statistically significant differences in dental components, including decreased inclination of the lower incisors, greater clinical crown length in the lower first incisors and the upper first molars, and smaller curve of Spee measurement, in the open-bite group compared with the normal over-bite group. Inclination of the lower incisors showed the most prominent detected difference (P < 0.001). The two groups demonstrated the most significant differences in skeletal components, with increased basal and mandibular angles, total and lower anterior facial heights, and maxillary posterior alveolar and basal heights. ConclusionsIncreased total anterior facial height, mandibular clockwise rotation, and increased maxillary posterior alveolar and basal heights were the predominant features of open-bite malocclusion influencing over bite. The inclination of the lower incisors was significantly decreased, indicating dentoalveolar adaptation to the backward rotation of the mandible.