Objective: This study aimed to evaluate maxillary and mandibular skeletal changes, and OP inclination changes in combined surgical-orthodontically treated patients skeletal class III patients by Bilateral sagittal split osteotomy setback. Further analyze the variations of OP inclination related to functionality, esthetics, and subset-based dentition analysis, and analyze the correlation between skeletal and Occlusal plane parameters. Methods: A research for the pre besides post treatment cephalograms in patients with a mean age of 23± 2.7 years who met the requirements for inclusion was conducted. The skeletal and occlusal plane parameters were mapped and calculated using the programme of Ilexis, (Sweden) FACAD AB-2017 Version 3.9.0. To compare the variables between occlusal parameters and skeletal pre in addition post treatment the opposite t-test was used. The Correlations between skeletal parameters and occlusal plane variables were determined with the bivariate correlation coefficient. Results: The results show a very high statistically significant increase in the FOP and BOP. However, based on the inclination changes of OP related to subset dentitions, the maxillary dentition shows no significant changes. The inclination of OP related to mandibular subset dentition shows significant changes. The correlation analysis reveals a skeletal parameter of the inclination of the mandible relates to the changes in the inclination of OP. Conclusion: The surgical-orthodontic approach involving BSSO setback resulted in a significant change concerning the occlusal lane inclination.