Inferior alveolar nerve injury associated with implant surgery

Inferior alveolar nerve (IAN) is the most commonly injured nerve (64.4%) during implant treatment. At present, no standardized protocol exists for clinicians to manage IAN injury related with implant surgery. Therefore, the purposes of the present article were to analyze the reasons for nerve injury and to propose guidelines in managing IAN injury.

Patients with IAN sensory disturbances after implant treatment were recruited for the study. Sixteen patients, eight men and eight women, with a mean age of 52.2 ± 8.1 years participated in this study. Patient examination, treatment, and IAN sensory function recovery monitoring were performed following six-step IAN injury during dental implant surgery (IANIDIS) protocol. The control group was composed of 25 healthy volunteers who never had IAN sensory disturbances or any trauma in the maxillofacial region.

The IAN sensory disturbances were scored as following: 5 (31.25%) had hyperalgesia and 11 (68.75%) expressed hypoalgesia. The mean asymmetry index (AI) was calculated for each patient and varied from 0.6 to 3.2. Overall, 31.3% of nerve injury patients were classified as mild, 31.3% as moderate, and remaining 37.5% as severe injury. All patients were successfully treated with proposed IANIDIS protocol.

The most frequent (50%) risk factor for IAN injury was intraoperative bleeding during bone preparation. The most common (56.3%) etiological risk factor of nerve injury was dental implant. A six-step protocol aimed at managing patients with IAN injury, during dental implant surgery, was a useful tool that could provide successful treatment outcome.