Ramus Height and Its Relationship with Skeletal and Dental Measurements

Background: The purpose of this study was to assess mandibular ramus height and to assess the relationship of ramus height with various craniofacial and dental measurements in a sample of Iraqi adults with skeletal and dental Class I. Materials and method: The sample consisted of 95 Iraqi adults (54 females and 41 males) having normal occlusion and Class I skeletal pattern aged between 18 and 31 years. Each individual was subjected to clinical examination and digital true lateral cephalometric radiography. The radiographs were analyzed using AutoCAD 2007 software computer program to determine ten linear and seven angular measurements. Descriptive statistics were obtained and independent samples t-test was performed to evaluate the gender differences, while Pearson’s correlation coefficient test was used to identify correlations between ramus height and other measurements. Results: All linear measurements were significantly higher in males, while angular measurements showed non-significant differences between males and females, except for SN-MP, SN-PP, and N-S-Ar angles which were significantly higher in females than in males. For both genders, there were significant positive correlations between ramus height and posterior facial height, maxillary and mandibular molar dentoalveolar heights, while there were significant negative correlations with SN-MP, PP-MP, and Ar-Go-Me angles. Ramus height in females showed a significant positive correlation with N-S-Ar angle, and a significant negative correlation with S-Ar-Go angle. Conclusions: Ramus height was directly correlated with intermaxillary space in the posterior region, and inversely correlated with angles of mandibular rotation.