INFERIOR ALVEOLAR NERVE INJURY IN MANDIBULAR ANGLE FRACTURES- A STUDY

Abstract

Objective: The purpose of this study is to determine displacement of inferior dental canal and associated inferior alveolar nerve injury in mandibular angle fractures.
Meterial and Methods:This study was carried on 117 patients with mandibular angle fractures in the Department of Oral & Maxillofacial surgery, Khyber College of Dentistry Peshawar from August 2012 to July 2013. The subjective complaint of lip numbness was noted preoperatively and light touch neurosensory testing was done objectively. Displacement of inferior dental canal was noted on Orthopantomogram (OPG) and categorized as nondisplaced, 1-3mm displacement, 4-6 mm and 6-9mm displacement.
Results:A total of 117 patients with mandibular angle fracture were included in the study. Amongst them 104 (88.9%) were males. The age ranged from 16 to 55 years with a mean age of 22.77± 6.704 years. Majority of the patients were in the age group of 16-25 years (78.6%). The inferior alveolar nerve injury was present in 75 patients (64.1%) while 42 patients (35.9%) had no symptoms of nerve injury. In 41 patient (35%) there was no displacement of inferior dental canal, out of which 12 patients had nerve injury while rest of 29 patients had no symptoms of nerve injury. In 40 patients (34.2 %) who had 1-3 mm of displacement of inferior dental canal only 28 patients had nerve injury while the nerve injury was present in all of the 13 patients (11.1 %) who presented with 7-9 mm of displacement of inferior dental canal on OPG.
Conclusion:Majority of patients having mandibular angle fractures and inferior dental nerve injury are young males. Inferior dental canal displacement of more than 3mm on OPG confirms inferior alveolar nerve injury. Non-displaced mandibular angle fractures on OPG do not exclude inferior dental nerve injury.