A Clinico-Radiological Study to Evaluate the Risk of Inferior Alveolar Nerve Damage in Impacted Mandibular Third Molar Removal

IntroductionImpacted mandibular third molar (IMTM) extraction, is the most commonly performed surgical procedure in oral and maxillofacial surgery, which may present with post-op complications like Inferior Alveolar neurosensory deficit (IANSD). Risk factor assessment by correlating pre-op OPG, CBCT findings with intra-op parameters provides a comprehensive tool for predicting nerve injury which forms the basis of this clinico-radiological study.Materials and MethodHundred patients with IMTM taken up for transalveolar extraction secondary to varied etiologies, were evaluated for post-op IANSD while comparing pre-op OPG and CBCT association with Intra-op parameters like hemorrhage, odontectomy, bone removal and physical observation of the canal. Affected patients on the 7th day were then followed up for 14th day, 01 month and 6 months for evaluating resolution of neurosensory deficit.ResultsA total of n = 9 out of 100 patients presented with post-surgical IANSD. Pre-op OPG findings of loss of white lines, deflection of roots and CBCT findings of inferior and lingual canal position were predominant attributable factors (p = 0.017). Intra-operatively, hemorrhage (p = 0.001), bone removal (p = 0.016) and odontectomy (p = 0.427) were associated with deficit in decreasing order while canal observation was definitely associated with IANSD (p = 0.007). All the patients recovered at 06 month follow up depicting only transient neurosensory deficit in our study sample.ConclusionVaried anatomic orientation of IMTM and its intimate association with IANC may pose as an indicator of post-op IANSD causing both surgeon and patient dissatisfaction. It is, thus, important to assess tooth and canal complex thoroughly and educate the patients about possible IANSD complication after correlating them with intra-op findings to avoid undue clinical surprises.