Does Collagen Membrane Coverage Offer any Advantage for Lateral Window Sinus Augmentation? A Histologic and Histomorphometric Analysis.

Abstract

Background: We aimed to determine whether collagen membrane coverage in maxillary sinus floor elevation surgery, provides an advantage regarding bone regeneration.

Methods: This randomized clinical trial included all healthy adults presented for dental implant placement in the posterior edentulous maxilla at the Maxillofacial Surgery Department of Mashhad Dental School, Mashhad, Iran from 2021-2022. Participants were candidates for sinus floor elevation surgery. Patients were randomly allocated to control (with membrane) and test (without membrane) groups. Surgery was performed through the lateral window technique and using allograft particles. According to the assigned study group; either a collagen membrane was placed over the osteotomy window or it was left uncovered. Six months after surgery when patients were recalled for implant placement, a bone specimen was obtained and sent for histologic and histomorphometric analysis. The predictor variable was the use of collagenous membrane and the outcome variables were the amount of newly formed bone, native bone, and connective tissue.

Results: A total of 30 consecutive patients, with a mean age of 46.33±7.25 years completed the study. Histomorphometric measurements, six months after augmentation revealed that the mean area of connective tissue was significantly less in the group with membrane coverage (P=0.015). The area of newly formed bone was significantly greater in sites covered with a collagen membrane compared to grafted but uncovered sites; (P <0.001).

Conclusion: Covering the lateral osteotomy window with a bioabsorbable collagenous membrane is able to significantly enhance vital bone formation and decrease connective tissue proliferation.