Porous Titanium Granules Used as Osteoconductive Material for Sinus Floor Augmentation: A Clinical Pilot Study

Resorption of grafting material may lead to unpredictable long-term results when rehabilitating the resorbed posterior maxilla. Nonresorbable, osteoconductive bone substitutes may therefore be an advantage over autogenous bone grafts. The aim of the present pilot study was to test titanium granules as bone substitute in patients planned for augmentation of the sinus floor prior to or in conjunction with placement of dental implants. Sixteen patients with uni- or bilateral edentulism and need for augmentation of the sinus floor were included in the study. Residual bone height was 2 to 5 mm. Grafting and installation of the dental implants (18 fixtures) was carried out in the same session if primary stability of the implants could be achieved (12 patients). A staged protocol with implant placement 3 to 7 months after the augmentation procedure was used when primary implant stability was impossible to achieve (four patients). In all, 23 TiOblast (TM) (Astra Tech AB, Molndal, Sweden) implants were installed. The patients have been followed 12 to 36 months after prosthetic loading. Three implants were found mobile and were removed (13.0%). Two of these were in patients where grafting and implant installation were carried out in separate procedures. The implants were found mobile at abutment connection and were removed. One patient in the single-stage group had a postoperative sinus infection, which was successfully treated with antibiotics. However, one out of two implants in this patient was found mobile and was removed after 1 year in function. In the present study, titanium granules seem to function as augmentation material in the sinus floor. It is, however, not clear if the material can be safely used for two-stage procedures. Further investigations with longer healing time before implant installation are required. Also, the possible risk of granule displacement during preparation of the fixture site should be further investigated. Additionally, biopsies from patients are requested to confirm any bone ingrowth between the granules.