The purpose of this investigation is to compare new bone formation through histomorphometric analysis following maxillary sinus augmentation using three different bone graft materials. Null Hypothesis is that there is no histomorphometric difference in new bone formation in maxillary sinuses augmented using three different materials; anorganic bovine bone graft (Bio-Oss), anorganic equine bone graft (Equimatrix) and mineralized bone allograft (OSSIF-i sem). Patients who require sinus augmentation prior to implant placement will be selected to participate in this study. All patients will be randomly placed into three groups according to bone graft materials that will be used. Group A (Control group,n=10): Maxillary sinus augmentation using anorganic bovine bone graft (Bio-Oss), Group B (Test group,n=10):Maxillary sinus augmentation using anorganic equine bone graft (Equimatrix), and Group C (Test group,n=10):Maxillary sinus augmentation using mineralized bone allograft (OSSIF-i sem). All the patients will be treated with the same surgical technique consisting of sinus floor augmentation via a lateral approach.After a full-thickness flap reflection to expose the lateral wall of the sinus each antrostomy will be outlined with a carbide round bur and sinus membranes will be carefully elevated. If a perforation to the sinus membrane occurs, and if the perforation is < 5 mm in diameter and is able to be repaired, the surgeon will continue the procedure. Any perforation > 5 mm will be excluded from this study. Bone graft materials will be placed into the each sinus compartment for the three groups. After 8 months of healing, biopsy specimen will be collected from the previous antrostomy sites. Histomorphometric measurements of the percentage of vital bone of the area of bone. The percentage of non-bone material (allograft or xenograft) and the percentage of connective tissue will be also analyzed. Then the primary hypothesis will be analyzed statistically.