Maxillary sinus floor elevation with bovine bone mineral combined with either autogenous bone or autogenous stem cells: a prospective randomized clinical trial.

AIM: To assess whether differences occur in bone formation after maxillary sinus floor elevation surgery with bovine bone mineral (BioOss(®)) mixed with autogenous bone or autogenous stem cells. The primary endpoint was the percentage of new bone three months after the elevation procedure.

MATERIAL AND METHODS: In a randomized, controlled split-mouth design, in 12 consecutive patients (age 60.8 ± 5.9 years, range 48-69 years) needing reconstruction of their atrophic maxilla, a bilateral sinus floor augmentation procedure was performed. Randomly, on one side the augmentation procedure was performed with bovine bone mineral (BioOss(®)) seeded with mononuclear stem cells harvested from the posterior iliac crest (test group) while BioOss(®) mixed with autogenous bone (harvested from the retromolar area) was applied on the contra-lateral side (control group). On 14.8 ± 0.7 weeks after the sinus floor elevation, biopsies from the reconstructed areas were taken at the spots where subsequently the endosseous implants were placed. The biopsies were histomorphometrically analyzed.

RESULTS: Significantly more bone formation was observed in the test group (17.7 ± 7.3%) when compared with the control group (12.0%± 6.6; P=0.026). In both the test and control group, all implants could be placed with primary stability. In one patient, not all biopsies contained BioOss(®). This patient was excluded from analysis.

CONCLUSION: Mesenchymal stem cells seeded on BioOss(®) particles can induce the formation of a sufficient volume of new bone to enable the reliable placement of implants within a time frame comparable with that of applying either solely autogenous bone or a mixture of autogenous bone and BioOss(®). This technique could be an alternative to using autografts.