The role of cortical perforations in allogeneic block grafting for lateral augmentation in maxilla: A randomized clinical trial

Abstract

Background The need of decortication on the recipient site remains unclear for bone regeneration. To our knowledge, there are no human clinical trials that studied the influence of decortication on cancellous allogeneic block grafting. Purpose The aim of the present study is to evaluate the influence of perforating the cortex of the recipient site on cancellous allogeneic block graft integration and revascularization in the maxilla. Material and Methods Twenty‐six patients referred for lateral bone augmentation were included in this clinical trial. Patients received freeze‐dried bone allograft cancellous blocks obtained from the iliac crest; cortical perforations of the recipient bed were performed in the test group while in the control group it was left intact. After a 4‐month healing period another surgery was performed to place dental implants, and a bone biopsy was collected using a trephine. All samples underwent micro‐CT scans, and were processed for histomorphometric and immunohistochemical analysis. Implant survival comparisons were made using a repeated measures analysis of variance (ANOVA) while all other variables were compared using the analysis of covariance (ANCOVA). Results One hundred and nineteen implants were placed into 110 augmented sites. One hundred percent implant survival rate was reported during 24 months follow‐up period. No differences were reported in bleeding on probing at 1 (5.6 vs 9%) and 2 years (13.2 vs 12.1%), probing pocket depth at 1 (3.4 ± 0.95 vs 3.6 ± 1.12 mm) and 2 years (3.8 ± 1.02 vs 4.1 ± 1.46 mm), and marginal bone loss at 1 (0.2 ± 0.52 vs 0.3 ± 0.57 mm) and 2 years (0.6 ± 0.91 vs 0.5 ± 0.87 mm). No statistically significant differences were found in the micro‐CT and histomorphometric analysis in terms of newly formed bone (25.7 ± 11.2% vs 22.3 ± 9.7%), soft tissue (33.0 ± 14.7% vs 36.5 ± 15.7%), remnant allograft (39.3 ± 20.4% vs 41.2 ± 22.7%), and bone mineralization (57.2 ± 10.6% vs 53.8 ± 8.7%). Perforating the cortex of the recipient site had no significant effect on angiogenesis as shown by immunohistochemical analysis of CD34 positive blood vessels (39.21 ± 10.53/mm2 vs 34.16 ± 12.67/mm2). Conclusion Cancellous allogeneic bone block grafts are a clinically acceptable alternative for horizontal bone augmentation. Cortical perforations of the recipient site in the maxilla did not improve angiogenesis nor bone formation within the block graft.

Allograft Customized Bone Blocks for Ridge Reconstruction: A Case Report and Radiological Analysis

“…Apart from the fit of the graft, the defect site preparation might have an influence on the integration and vascularization of the block graft. Tresguerres and coworkers showed that cortical perforation of the recipient site did not influence the angiogenesis and new bone formation compared to nonperforated sites [40]. In this presented case report, there was uneventful healing, resulting in minimal to no volume loss of the customized allograft bone block 5 months after placement, and the histology after 6 months showed 46.61% mineralized bone, similar to the previous published results [40].…”

“…Tresguerres and coworkers showed that cortical perforation of the recipient site did not influence the angiogenesis and new bone formation compared to nonperforated sites [40]. In this presented case report, there was uneventful healing, resulting in minimal to no volume loss of the customized allograft bone block 5 months after placement, and the histology after 6 months showed 46.61% mineralized bone, similar to the previous published results [40]. After three months of healing, the implant stability showed ISQ values over 70.…”

The allogeneic shell technique for alveolar ridge augmentation: a multicenter case series and experiences of more than 300 cases

“…The defect was cleaned from connective tissue residues without decortication of the local bone and the defect size was measured with a sterile caliper. In this context, there is no evidence according decortication benefits [ 41 , 42 ]. Then, CP were adjusted and trimmed to the correct size by a cutting disc after rehydration in 0.9% saline at room temperature for at least 10 min to increase CP breaking strength and flexibility [ 35 ].…”