Assessment of the Quality and Quantity of Bone Regeneration

Eligible patients will be randomly assigned into one of two treatment groups using a randomization table generated by a computer. The test group (10 sinuses) will receive Osteocel Plus and control group (10 sinuses) will receive conventional cortical-cancellous particulate allograft material. The objective of this research is to serve as a pilot study, gathering information that will guide the design of a larger subsequent study. Little is known about the distribution of bone quality changes in patients who receive Osteocel Plus graft to augment the maxillary sinus. Ten subjects per group is reasonable for a pilot study, providing an 89% probability of estimating the true mean for bone quality and implant stability to within half a standard deviation in each group. These means, along with the observed standard deviations and within-subject correlations that the investigators obtain will prove essential for designing the larger, confirmatory study that constitute the next phase of this research.

A clinical radiographic/surgical guide will be fabricated for each patient to be used for CBCT scan prior to sinus augmentation procedure. The same clinical radiographic/surgical guide will be used for CBCT scan prior to the implant placement to measure the amount of bone regeneration following four months of healing at the exact sites. One line will measure the horizontal width and the other line will measure the vertical height. The horizontal width will be measured at a vertical height of 10 mm from the sinus floor in the sinus cavity based on the conventional average length of dental implant used in implant dentistry. The difference in the measurements for all surgical sites after the grafting procedure and before the implant placement will provide a clinical assessment of the amount of bone regeneration.

Forty trephined core samples will be retrieved surgically from two areas of the grafted lateral window at the time of implant placement. One core sample will be retrieved from the anterior area, approximately 4 mm distal to the anterior tack which was used to fix the resorbable membrane, and the other one will be retrieved from the posterior area, approximately 4 mm mesial of the posterior tack which was used to fix the resorbable membrane. Histomorphometric analysis will be performed on three fields for each section using specialized software. Volume of vital bone, graft remnants, and connective tissue will be measured based on the averages of the percentages at a magnification of 63X. Data will be statistically analyzed using Statistical Package for the Social Sciences (SPSS 13.0 for Windows software) program to compare between test and control groups.