The purpose of this report was to provide data regarding whether the use of alloplastic implants to the mandibular body and angle as an occasional adjunct to orthognathic surgery affects the jaw reflex. Two patients to whom sagittal split osteotomy with Medpor porous polyethylene implant was performed due to severe mandibular asymmetry were included. To elucidate alterations in reflexes, serial surface electromyographic data were collected from the masseter muscle. The latencies and durations of the silent period were measured. In both patients, massetery inhibitory reflex response on the Medpor-augmented side was not elicited at the postoperative first month. Although postoperative masticatory inhibitory reflex latencies, durations, and configurations were similar between the right and left sides in both patients, we did not elicit the first silent period response following porous polyethylene implant placement at the postoperative sixth month. In conclusion, porous polyethylene implants may decrease masticatory reflex activity. The clinical use of implants made of porous polyethylene seems to be safe; however, indications, chances, and risks should be carefully evaluated prior to application.
