Evaluation of mesiodistal inclination of permanent maxillary and mandibular first molars in different Angle's molar relation: A cephalometric study

Introduction: Angle's molar relationship is the most widely used classification in spite of the introduction of various other classifications. At the end of the treatment, the molars are finished in a Class I, II, or III molar relation. Thus, it is important to know the ideal inclinations of upper and lower 1st molars, thereby assisting in achieving a stable relationship. Aims and Objectives: The aim and objective of this study was to evaluate the mesiodistal inclination of permanent maxillary and mandibular first molars in Angle's Class I, II, and III molar relationships in relation to the occlusal plane. Methodology: Lateral cephalograms of 16–30-year-old individuals with Class I, II, and III molar relations were selected and traced in Dolphin imaging software, and the angle between the first molar and occlusal plane was calculated. Results: There was a statistically significant difference in the inclination of maxillary 1st molar in between Class I and Class III. No significant difference was noted in the inclination of maxillary first molar in case of Class I and Class II. In case of mandibular molars, there was a statistically significant difference in case of Class I and Class II and between Class I and Class III. Conclusion: When the end molar relationship of a case is planned to be Class I, the upper molar should be at an angle of 84.12° to the occlusal plane. When the end molar relationship of a case is planned to be Class II, the upper molar should be 84.15° to the occlusal plane. When the end molar relationship of a case is planned to be Class III, the upper molar should be inclined at an angle of 87.07° to the occlusal plane.