Maxillary Sinus Floor Augmentation With Autogenous Bone Graft Alone or in Combination With Symbios Biphasic Bone Graft Material or Symbios Xenograft Granules. A Randomized Controlled Trial

Maxillary sinus floor augmentation (MSFA) is the most frequently used method to enhance the alveolar bone of the posterior maxilla before or in conjunction with implant placement. Autogenous bone is considered as the preferred graft material due to its osteoinductive, osteogenic and osteoconductive characteristics. However, autogenous bone grafts is associated with risk of donor site morbidity and unpredictable graft resorption. Hence, various bone substitutes are used increasingly to simplify the surgical procedure by diminishing the need for bone harvesting. From a clinical and patient perspective, it would be an advantage, if autogenous bone grafts could partially or totally be replaced with bone substitutes.

Symbios xenograft is a new porcine bone mineral characterized as an anorganic bone matrix with an interconnecting macro- and microscopic pore structure that supports formation and in-growth of new bone. Porcine xenograft have previously been used for various augmentation procedures disclosing new bone formation. Studies comparing autogenous bone graft with porcine bone alone or a mixture of autogenous bone and porcine bone have demonstrated high implant survival and new bone.

Synthetic biomaterials including calcium phosphate, calcium sulphate, polymers and bioactive glass represent a large group of inorganic diverse biomaterials with variating structures, chemical composition and physical properties. Symbios biphasic biomaterials is a resorbable inorganic bone forming material derived from red algae consisting of 20% hydroxylapatite and 80% β-tricalciumphosphate. Studies assessing MSFA with β-tricalciumphosphate have demonstrated that it is a safe grafting material with osteoconductive properties. Histologic and radiographic examinations indicate that β-tricalciumphosphate is slowly resorbed and replaced with bone. MSFA with β-tricalciumphosphate alone or in combination with autogenous bone or other bone substitutes have demonstrated high implant survival and new bone.

The study purpose is to increase our knowledge about MSFA with autogenous bone alone or in combination with Symbios biphasic biomaterials or Symbios xenograft granules and to simplified the procedure. Evaluation will include survival of suprastructures and implants, peri-implant marginal bone level, volumetrical stability of the graft and complications after an observation period of one year. Furthermore, oral health related quality of life, using OHIP-14 self-administrated and patient satisfaction using visual analogue scales (VAS), will be evaluated.

The objective is to test the H0 hypothesis of no differences in 1) Survival of suprastructures and implants, 2) Volumetrical stability of the graft, 3)Peri-implant marginal bone level, 4) Implantat stability quotient, 5) Patient-reported outcome measures, and 6) Biologic and technical complications.