This systematic review evaluated the implant survival rate, changes in marginal bone level, and complications associated with guided surgery for the treatment of fully edentulous patients followed up for longer than 1 year. A comprehensive literature search was conducted in MEDLINE/PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) to retrieve studies published up until July 2014 that met predefined eligibility criteria. Thirteen studies were included. In studies on the guided surgery technique, a survival rate of 97.2% and a mean marginal bone loss of 1.45 mm were found during 1–4 years of follow-up. However, associated complications, such as implant loss, prosthesis or surgical guide fractures, and low primary stability, were often found, and there is a learning curve to achieve treatment success. Further longitudinal comparative studies should improve the technique and its success rate.
Since the development of osseointegrated implants and the publication of the first longitudinal studies evaluating their success and survival, the primary focus of contemporary implant dentistry has been the investigation of less invasive and more predictable surgical techniques that result in reduced treatment times.
In the last few years, clinical studies have reported excellent results for the techniques developed to replace bone regeneration procedures and avoid implant placement close to critical anatomical areas, such as the maxillary sinus and the mandibular nerve. Krekmanov et al. described a distal implant inclination technique for use in cases where implant placement in the posterior region is contraindicated. The combination of distal tilted implants, immediate prosthetic loading, and a smaller number of implants has recently been recommended for use with All-on-Four (four implants) and Novum (three implants) systems, which have survival rates comparable to those of conventional techniques. However, the accurate placement of tilted implants or implants close to important anatomical areas using free-hand techniques remains a challenge for surgeons.
The advent of cone beam computed tomography (CBCT) has contributed to the development of guided surgery techniques. The use of CBCT to plan the placement of implants and the use of surgical guides, aided by specific software, preclude the use of a flap. The advantages of not raising a mucoperiosteal flap are reduced surgery times, fewer postoperative complications such as pain and bleeding, and greater patient comfort. Moreover, recent studies have found better healing and lower rates of alveolar and peri-implant bone loss when using this technique.
This systematic review and meta-analysis evaluated implant survival rates, changes in marginal bone levels, and complications associated with guided surgery for the treatment of fully edentulous patients followed up for longer than 1 year.
Materials and methods
Development of a protocol
The method used in this systematic review was adapted from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the recommendations made by Needleman. Clinical questions were developed and organized according to the PICO framework for evidence-based practice.
The focused question was ‘What are the implant survival rates, marginal peri-implant bone changes, and complications of guided surgery for the treatment of fully edentulous patients after a 1-year follow-up?’