This article presents a novel method of navigation-guided lateral gap arthroplasty (LGA) in the treatment of temporomandibular joint ankylosis (TMJA).Six patients with unilateral TMJA from 2007 through 2011 were included in this study. Presurgical planning was performed to determine the amount and extent of ankylosed bone to be resected using the simulation platform. Minimum follow-up was 6 months. Patients were monitored for complications and signs of recurrence. Maximum mouth opening (MO) was measured and compared intra- and postoperatively.Preoperative planning was performed at the STN or Accu-Navi workstation. The amount and extent of ankylosed bone to be resected was determined. All 6 LGAs were completed successfully using real-time instrument- and pointer-based navigation. Measurements performed intraoperatively showed that the mean for maximum MO was about 35 to 40 mm and remained the same postoperatively. Follow-up evaluation showed remarkable improvement in function and esthetics, with no signs of recurrence.Navigation-guided LGA can be regarded a viable option for performing this delicate and complicated surgical procedure.