Osteogenic Potential of Bovine Bone Graft in Combination with Laser Photobiomodulation: An Ex Vivo Demonstrative Study in Wistar Rats by Cross-Linked Studies Based on Synchrotron Microtomography and Histology.

Ruxandra Elena Luca,Bogdan Hoinoiu,Adrian Mănescu,Rodica Heredea,Carmen Darinca Todea,Virgil-Florin Duma,Alessandra Giuliani,George Dumitru Constantin

doi:10.3390/ijms21030778

Abstract

Background: Alveolar bone defects are usually the main concern when planning implant treatments for the appropriate oral rehabilitation of patients. To improve local conditions and achieve implant treatments, there are several methods used for increasing bone volume, among which one of the most successful, versatile, and effective is considered to be guided bone regeneration. The aim of this demonstrative study was to propose an innovative analysis protocol for the evaluation of the effect of photobiomodulation on the bone regeneration process, using rat calvarial defects of 5 mm in diameter, filled with xenograft, covered with collagen membrane, and then exposed to laser radiation. Methods: The animals were sacrificed at different points in time (i.e., after 14, 21, and 30 days). Samples of identical dimensions were harvested in order to compare the results obtained after different periods of healing. The analysis was performed by cross-linking the information obtained using histology and high-resolution synchrotron-based tomography on the same samples. A comparison was made with both the negative control (NC) group (with a bone defect which was left for spontaneous healing), and the positive control (PC) group (in which the bone defects were filled with xenografts and collagen membrane without receiving laser treatment). Results: We demonstrated that using photobiomodulation provides a better healing effect than when receiving only the support of the biomaterial. This effect has been evident for short times treatments, i.e., during the first 14 days after surgery. Conclusion: The proposed analysis protocol was effective in detecting the presence of higher quantities of bone volumes under remodeling after photobiomodulation with respect to the exclusive bone regeneration guided by the xenograft.

Highlights

Nowadays, dental medicine is confronted with the challenge of solving large edentations complicated with severe bone loss through the usage of implant prosthetic restorations
Two aspects are evident in the 3D reconstructions of the represented samples: first, the newly-formed bone mainly forms on the borders and not in the center of the defect, and this occurs in the negative control (NC) group, and in the positive control (PC) and +level laser therapy (LLLT) groups; secondly, with the exception of the +LLLT group, an increase in the volume of newly-formed bone is evident in the period between the 14th and the 21st day after surgery
The study, in order to minimize the number of sacrifices, included 24 Wistar rats with an average weight of 287 g, which were randomly divided into 3 study groups: (1) the negative control (NC) group, having a bone defect which was left for spontaneous healing; (2) the positive control (PC) group, in which the bone defects were filled with xenografts and collage membrane, without receiving any laser treatment; and (3) the test (+LLLT) group, with bone defects filled with xenografts, with collagen membrane and receiving low level laser irradiation every 48 h

Summary

Introduction

Dental medicine is confronted with the challenge of solving large edentations complicated with severe bone loss through the usage of implant prosthetic restorations. To improve local conditions and to give the patient the possibility to receive an appropriate implant treatment, several methods and biomaterials for increasing the bone volume have been tested. To improve local conditions and achieve implant treatments, there are several methods used for increasing bone volume, among which one of the most successful, versatile, and effective is considered to be guided bone regeneration. The aim of this demonstrative study was to propose an innovative analysis protocol for the evaluation of the effect of photobiomodulation on the bone regeneration process, using rat calvarial defects of 5 mm in diameter, filled with xenograft, covered with collagen membrane, and exposed to laser radiation. Conclusion: The proposed analysis protocol was effective in detecting the presence of higher quantities of bone volumes under remodeling after photobiomodulation with respect to the exclusive bone regeneration guided by the xenograft

Methods

Results

Discussion

Conclusion