OBJECTIVETo evaluate new bone formation and preliminary clinical outcomes following maxillary sinus floor augmentation with Bio-Oss alone.

METHODSNine patients were treated with ten maxillary sinus floor augmentations using Bio-Oss alone, and eighteen Straumann implants were placed. After five to eleven-month healing period at implant placement, cylindrical specimens were biopsied from the augmented area. The new bone formation of specimens was analyzed by histology and micro-computed tomography. Cone beam computed tomography (CBCT) scans were performed for measurements of residual crestal bone height under the sinus, the amount of increased height immediate after the augmentation and before implant insertion. To monitor stability changes, resonance frequency analysis was performed and implant stability quotient (ISQ) values were collected at implant placements (baseline,0 month), one month, three months and six months after placements.

RESULTSAll implants were loaded six months after insertion and no failures were recorded. Compared to adjacent native bone, no significant differences of bone volume fraction were found in augmented area (P > 0.05), together with lower trabecular number (P < 0.05) and trabecular thickness (P < 0.01) as well as higher trabecular separation (P < 0.01) by microradiographic analysis.Histomorphometrically, there was no significant difference in the amount of new bone formation between the adjacent native bone and augmented area (P > 0.05). CBCT showed a bone height gain of (14.19 ± 2.02) mm immediate after augmentation, which stabilized at (13.68 ± 1.95) mm after bone healing period. Mean ISQ value was 71.94 ± 6.51 at baseline, decreased to 70.19 ± 6.38 at 1 month, and increased to 78.17 ± 3.83 at 3 month and 82.56 ± 3.20 at 6 month.

CONCLUSIONSThe use of Bio-Oss as the sole graft is reliable and can lead to satisfactory bone formation and clinical outcome.