Clinical Success of Dental Implants Placed in Posterior Mandible Augmented With Interpositional Block Graft: 3-Year Results From a Prospective Cohort Clinical Study

Abstract

The purpose of the present cohort study was to investigate the 3-year efficacy and clinical performance of implant-supported rehabilitations in posterior mandibles augmented with the sandwich osteotomy technique. Twenty-three partially edentulous patients who developed atrophy of the posterior mandible (residual ridge height, 3 to 7mm) were treated (32 surgical sites) with vertical bone augmentation using interpositional equine cancellous bone blocks and porcine corticocancellous bone particulate. All implants were placed 4months after augmentation and were loaded with fixed dental prostheses. One side per patient was selected and followed for 3years, and the patient was the unit of analysis. Linear radiographic vertical bone gain and peri-implant marginal bone loss were assessed; secondary outcomes-complication rates after surgery, prosthesis and implant failure rates, width of keratinized mucosa, and patient satisfaction-were evaluated. All patients reported postoperative paresthesia that resolved over a period of 2months after the augmentation procedure. The mean vertical bone gain was 5.6mm after 4months. Ninety-one dental implants were positioned into the augmented areas. The global 3-year survival rate was 95.5%. The mean peri-implant marginal bone loss around implants was 1.06±0.37mm 3years after loading, whereas the width of keratinized mucosa had an overall increase of 0.39±0.36mm. The results of the present 3-year study suggested high success rates for implants placed in areas augmented with the osteotomy sandwich technique. This surgical approach could be helpful in the presence of a low residual vertical height in the posterior mandible before implant placement.