Characteristics of Medial Depressionof the Mandibular Ramus in Patients with Orthodontic Treatment Needs:A Panoramic Radiography Study

摘要

Background: Medial sigmoid depression or medial depression of the mandibular ramus (MDMR) is a known variant of the normal radiographic anatomy. The clinical importance of MDMR has been recognized, however, its prevalence and association with patients with orthodontic needs have been poorly documented. Aims and Objectives: To estimate the prevalence and characteristics of MDMR on panoramic radiographs of patients with different Angle?s molar relation. Materials and Methods: Three hundred panoramic radiographs of 100 each belonging to patients with Angle?s class I, II and III molar relationship was recruited from an orthodontic clinic. The radiographs were evaluated for presence of MDMR along with its characteristics such as site and shape. The data was entered in the proforma and subjected for statistical analysis. Results: The overall prevalence of MDMR in the present study was 23.2%. MDMR was found to be more prevalent in Class II ? 28 (9.3%) followed by class III-23 (7.6%) and Class I- 19 (6.3%). There was equal distribution of MDMR with respect to site and the semilunar shape was the most common 36 (34%). All these findings were statistically non-significant. Conclusion: Although MDMR is considered as a normal radiographic finding, the present study confirms the disparity in the prevalence of MDMR in patients with dentoskeletal deformities. Thus our findings suggest the importance of recognizing this entity prior to orthognathic surgery so as to avoid untoward sequelas.