The aim of the study is to compare the prevalence of post-operative inferior dental nerve (IDN) deficit after coronectomy with total removal of wisdom teeth showing specific radiographic signs of close proximity to IDN. A randomized clinical trial comparing total removal and coronectomy of wisdom tooth was conducted. Analyses of the correlations of IDN deficit and various radiographic signs of wisdom tooth roots showing close proximity to IDN were performed. Two radiographic signs were found to be positive predictors ofintra-operative IDN exposure. Specific radiographic signs or the presence of two or more radiographic signs are positive predictors of post-operative IDN deficit. The study concluded that darkening of the wisdom tooth root and presence of two or more specific signs in radiographs significantly increased the risk of IDN deficit in lower wisdom tooth surgery. Coronectomy can significantly reduce the prevalence of an IDN deficit in patients with lower wisdom teeth showing radiographic signs of close proximity to IDN. It also carries less surgical morbidities when compared with total removal of lower wisdom tooth.