The Window Bone Chisel Sinus Augmentation Technique for Placing Short Implants in Patients with ≤ 3 mm of Residual Alveolar Bone. A Three-year Prospective Study
The objective of this study was to display a window bone sinus augmentation technique using a chisel combined with simultaneous short implant placement in the minimal edentulous posterior maxilla with 1-3 mm of residual bone height (RHB), as well as to evaluate the clinical effect in a prospective study. 167 short implants were installed in 107 patients in the severely atrophic posterior maxilla immediately after sinus floor elevation between January 2011 and November 2013. A window bone sinus augmentation technique using a chisel was applied in the surgical procedure. The mean residual bone height (mRHB) adjacent to or beneath the sinus was 2,99 ± 1,10 mm, ranging from 1,02 mm to 4,96 mm. A healing period of 6 months was observed for all implants. The final prostheses were restored 1 month later. At baseline and the follow-up appointments the stability and osseointegration of the implants were clinically evaluated, also the bone height gain around the implants was measured using SimPlant Planner 14.0® and Schick 33 Digital Sensor System CDR DICOM® softwares. The cumulative survival rate of the implants was 98,8% after a period of 6 to 36 months (22,33 months ± 10,20). The radiographic results demonstrated that mRBH gain after the restoration was 5,15 ± 1,55 mm. Based on the results and within the limits of the study, it can be suggested that short implant placement in conjunction with window bone sinus augmentation technique could yield predictable clinical results for edentulous posterior maxillary region with RBH less than 3 mm.