ABSTRACT
Objective: To evaluate the correlation between atlas morphology and maxillo-mandibular divergence
Study Design: Cross-sectional, analytic study
Place and Duration of Study:Dental Clinics, The Aga Khan University Hospital, Karachi, Pakistan from February to August 2017
Methodology: Pretreatment lateral cephalograms of 208 subjects, aged 18 to 25 years, were evaluated. The atlas parameters were categorized into atlas dorsum, anteroposterior and ventrum, and measured on View Pro-X software.Various maxillary [FPPP, SNPP and FHPP angles] and mandibular [SNGoGn, saddle, articulare, gonial, sum of posterior and Y-axis angles] parameters were used to evaluate the divergence pattern of the individuals. Mann-Whitney U-test was used to compare atlas and maxillo-mandibular parameters between genders. Spearman correlation was used to correlate atlas and maxillo-mandibular parameters across genders. A p-value
Results: Statistically significant differences were found between various atlas and maxillo-mandibular parameters between genders. With atlas dorsum, the saddle angle [r = -0.3] in males; whereas gonial [r = -0.2], Y-axis [r = 0.1] and SNPP [r = -0.2] angles in females showed significant weak correlation. With atlas anteroposterior, saddle [r = -0.2], articulare [r = 0.2], SNPP [r = -0.2] and FHPP [r = -0.3] angles in males showed significant weak correlation. However, only the SNPP angle [r = -0.2] in females showed a significant weak correlation with atlas ventrum
Conclusion: A weak correlation was found between atlas parameters and various maxillo-mandibular angular parameters in both genders. Therefore, atlas morphology cannot be regarded as a good predictor of future maxillo-mandibular divergence pattern.