A reduced healing protocol for sinus floor elevation in a staged approach with deproteinized bovine bone mineral alone: A randomized controlled clinical trial of a 5-month healing in comparison to the 8-month healing.

Abstract

To investigate the feasibility of reducing the healing time of maxillary sinus floor elevation (MSFE) by a two-stage approach using deproteinized bovine bone mineral (DBBM) alone, based on clinical, histomorphometric, and microradiographic evaluations. Twenty consecutive cases with an atrophic posterior edentulous maxilla were randomly assigned to two groups at a ratio of 1:1. The lateral window approach to MSFE with DBBM alone was followed by an 8-month bone-healing period in the control group compared to 5 months in the test group. During implant placement, bone biopsies were harvested from implant osteotomy sites for micro-computed tomography (CT), histological, and histomorphometric evaluations. Cone beam CT (CBCT) scans were performed before and immediately after MSFE and after the bone-healing periods. The implant stability quotient (ISQ) was measured sequentially at implant placement and 1, 3, and 6 months thereafter. The histomorphometric and microradiographic results showed no significant differences in new bone formation on the augmented sinus floor between the two groups (all Ps > .05), except that trabecular thickness was significantly reduced and trabecular separation significantly increased in the test group (both Ps < .05). The ISQs of both groups increased continuously after implant placement, but the difference was not significant between the groups at each time point. CBCT analyses showed that the extent of volumetric loss was comparable after bone healing for 5 and 8 months (P > .05). Within the limitations of this study, the bone-healing time of MSFE with DBBM alone for staged implant placement could be reduced to 5 months instead of 8 or 9 months, based on the histomorphometric, microradiographic, and clinical outcomes; however, impact on long-term implant survival remains unknown and needs further investigation with long-term follow-ups.