Patients' perception of sensory disturbances of the mental nerve before and after implant surgery: a prospective study of 110 patients.

In a randomized controlled clinical trial 110 edentulous patients with severe mandibular bone loss have been treated with ITI-dental implants using three different treatment strategies: (1) a mandibular overdenture supported by two implants with ball attachments, (2) two implants with an interconnecting bar or (3) by four interconnected implants. As implant surgery involves elevation of the mucoperiosteum, bone remodelling at the implant site and insertion of implants close to the mental foramen, altered sensations of the mental nerve caused by the surgery are to be expected. An altered sensation of the lower lip can also be caused by pressure of an ill-fitting lower denture on the mental foramen, or in the case of severe bone loss of the alveolar ridge, on the alveolar nerve itself. This article presents the results of the patients' perception of the sensation of their lower lip before, 10 days after and 16 months after implant surgery in the mandible. It shows that 25% of the patients describe a sensory disturbance before treatment. This 25% also showed high scores on the Hopkins Symptoms Check List indicating a tendency to somatize complaints. Eleven percent of the patients report a sensory disturbance in the lower lip 10 days after surgery. Ten percent report a sensory disturbance 16 months after surgery of which one third also reported a disturbance before the treatment. This implies the risk of a sensory disturbance of the lower lip to be a possible complication after implant surgery. Therefore patients must be informed about this phenomenon before treatment.