Evaluation of Guided Bone Regeneration in Critical Defects Using Bovine and Porcine Collagen Membranes: Histomorphometric and Immunohistochemical Analyses

Abstract

Guided bone regeneration (GBR) is a technique used to facilitate bone regeneration, which uses a biocompatible membrane acting as a physical barrier to prevent the adjacent connective tissue from invading the bone defect. The aim of this study was to evaluate and compare the effectiveness of bovine and porcine collagenous membranes as barriers to connective tissue invasion during the repair of critical bone defects in rat calvaria, using histological, histometric, and immunohistochemical analyses. For this study, 72 rats were divided into three groups: clot group (CG), bovine collagen group (BCG), and porcine collagen group (PCG). Analyses were performed on days 7, 15, 30, and 60. The histological results showed that the PCG exhibited bone neoformation starting from day 7, and after 30 days of repair, the surgical defect was completely filled in some animals. For the BCG, there was little bone neoformation activity in the initial periods, and from day 30 onwards, there was an increase in bone neoformation, with a greater increase on day 60. The data obtained in the histometric analysis reveal that, on day 30, the neoformed bone area did not vary greatly between the PCG and the BCG, though both varied from the CG. By day 60, the PCG presented a greater area of neoformation than the BCG. These results were corroborated by the immunohistochemistry results. In view of the results obtained, it can be concluded that all membranes studied in this research promoted GBR.

Efficiency analysis of commercial polymeric membranes for bone regeneration in rat cranial defects

“…Porosity is a very sensitive characteristic of GBR membranes, as nanometric porosities (pores of 0.004 μm) into collagen membrane are associated with the same amount of newly formed bone as the control group 40 . On the other hand, a greater porosity reduces the osteopromotive capacity, as in the case of a titanium membrane without pores, which reached a greater area of neoformed bone compared to both anodized membranes with pores of 0.4 and 1.5 mm, in the ratio 1.6:1, as well as increased immunoexpression of calcein for up to 7 weeks 41 . Surgitime PTFE features more interconnected synthetic polymer fibers, providing less permeability and greater mechanical resistance compared to GenDerm and Lumina-Coat, natural polymers with a heterogeneous distribution of collagen fibers, which gives them highly porous surfaces with varied diameters 42 , justifying the present results of biodegradation in natural membranes.…”

“…Semiautomated histomorphometric analysis with manual point counting in software along the length of the critical defect is used for initial estimation of inflammation and neovascularization between 7 and 15 days post-surgery [36][37][38] or for its main objective of analyzing the percentage of bone formation and maturity, secondarily evaluating connective tissue and residual biomaterial, between 1 and 3 months after surgery 4,17,39 . Despite the automated counting in software by delimited area in pixels converted into mm 2 is a fast resource and used with great popularity in thematic research 19,27,[36][37][38][40][41][42][43][44] , the semiautomated counting values the histopathological diagnosis, allowing the optical distinction of new bone from old or native bone at the edges of the bone defect, as well as fragments of collagenous biomaterial against connective tissue fibers, making the calculation of these parameters more accurate 4,17,39 . Such scientific evidence makes this research robust, unbiased and accurate for the analysis of osteopromotive membranes for GBR.…”

Photobiomodulation Therapy Improves Repair of Bone Defects Filled by Inorganic Bone Matrix and Fibrin Heterologous Biopolymer

“…The use of PBM favored technical repair, especially when associated with the biocomplex (bone graft + fibrin biopolymer) which, in turn, act as scaffolds that create a beneficial microenvironment for the process. The association of two three-dimensional scaffolds, such as bovine bone graft and a fibrin derivative, allows better accommodation and stability in the recipient bed, with greater vascular sprouting, essential factors for the success of a graft with bone formation [65][66][67].…”

Collagen Membranes Functionalized with 150 Cycles of Atomic Layer Deposited Titania Improve Osteopromotive Property in Critical-Size Defects Created on Rat Calvaria

“…The use of critical defects in rodent calvaria is a well-established experimental animal model widely used in the scientific community to evaluate bone remodeling process, osteopromotive and osteoconductive properties of materials with potential for guided bone regeneration [ 13 , 33 , 34 , 35 , 36 , 37 ] and it was the model chosen for this study. The results of this study clearly showed that the COL150 membrane yielded better biological behavior during the chronology of bone healing of defects created in rat calvaria, with an emphasis on the primary outcome, the area of newly formed bone between the remaining bone stumps.…”