ABSTRACT
@#With the aging of the population and the increase in the number of edentulous patients, implant-supported fixed restorations have become more prevalent in clinical treatment. It is necessary to assess the patient's remaining bone and occlusal situation correctly; the upper jaw usually needs 6 to 8 implants, whereas the lower jaw needs 4 to 6 implants. Patients with severe alveolar bone atrophy can adopt the "all-on-4/6" treatment plan, short implants, and zygomatic and pterygomaxillary implants to avoid complex bone grafting and remain cautious when the surgical procedures require more surgical experience. According to the repair methods, the superstructure can be divided into one-piece repair and segmental repair. One-piece repair has a lower implant number, flexible location, and reasonable stress distribution but a high maintenance cost. Sectional repair easily achieves passive placement, convenient cleaning, and maintenance in the late stages, but implants need quantity and high requirements for alveolar bone. However, the requirements for alveolar bone and implant number are high. Mutually protected occlusion with minimal or no cantilever on provisional prosthesis is recommended.
ABSTRACT
Objective @#The purpose of this study is to determine the accuracy of implant placement in the edentulous jaw using computer planning and fully-guided mucosa-supported surgical template by Simplant software.@*Methods@#63 implants were placed in 9 patients (11 fully edentulous jaws), 26 implants were placed in upper edentulous jaw and 37 implants in lower edentulous jaw. Preoperatively, first, a cone beam CT was required for patients with radiographic template and radiographic template respectively. Therefore, the data of CBCT was inputted in Simplant software by DICOM format, followed by virtual implant planning. Hereafter, a mucosa-supported surgical template was designed by dentist and made by Masterilise company to allow implant placement using the template as a guide. To investigate the accuracy of implant placement, a postoperative CBCT scan was obtained and matched to the preoperative scan. The accuracy of implant placement was validated three-dimensionally including divations of implant shoulder, apical point, axial angulation and depth.@*Results@#The survival rate of 63 implamts for a 6 month to 10 year observation period was 100%. The mean divation of implant shoulder was 0.73 ± 0.53 mm, implant apical point was 1.15 ± 0.62 mm, implant depth was 0.95 ± 0.64 mm and implant axial angulationwas 4.10 ° ± 3.23°.@*Conclusion @#Divation between virtual and actual implant was existed and it should be considered preoperatively when virtual implant was planned to avoid injuring anatomic structure and keeping surgery safely. Correct manipulation during implant operation are helpful to decrease the divation of implant placement.