Calvaria Critical Size Defects Regeneration Using Collagen Membranes to Assess the Osteopromotive Principle: An Animal Study

Abstract

Guided bone regeneration (GBR) is a common practice in implantology, and it is necessary to use membranes in this process. The present study aimed to evaluate the osteopromotive principle of two porcine collagen membranes in critical-size defects at rats calvaria. Ninety-six Albinus Wistar rats were divided into BG (positive control), JS, CS, and CG (negative control) groups and were sacrificed at 7, 15, 30, and 60 days postoperatively. The samples were assessed by histological, histometric, immunohistochemical, and microtomographic analyses. More intense inflammatory profile was seen in the JS and CS groups (p < 0.05). At 60 days, the JS group showed a satisfactory osteopromotive behavior compared to BG (p = 0.193), while CS did not demonstrate the capacity to promote bone formation. At the immunohistochemical analysis, the CS showed mild labeling for osteocalcin (OC) and osteopontin (OP), the JS demonstrated mild to moderate for OC and OP and the BG demonstrated moderate to intense for OC and OP. The tridimensional analysis found the lowest average for the total volume of newly formed bone in the CS (84,901 mm2), compared to the BG (319,834 mm2) (p < 0.05). We conclude that the different thicknesses and treatment techniques of each membrane may interfere with its biological behavior.

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

“…For the biocompatibility analysis, the group used as a control was the COL, as also used in previous publications [ 18 , 19 , 42 ]. The tested membranes for subcutaneous assessment had the same standardized surgical approach.…”

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

“…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.…”

“…In the experimental rat skull model, membranes for GBR alone can achieve different osteopromotive profiles. In the period of 1 and 2 months, the ratio of area of newly formed bone compared to control group can be two to ten times for Bio-Gide with collagens I and III from swine dermis 19,[36][37][38] or Jason with collagen III from porcine pericardium 38,42 , equal to five times for bovine GenDermFlex 19 , two to four times for Collprotect with collagen from porcine dermis 38 or Super Fixorb with polylactic acid and hydroxyapatite (60:40) 40 and two to three times for bovine GenDerm 19,42 , and for synthetic membrane with policaprolactone and 5% hydroxyapatite 37 . There are cases such as the Biomend with collagen I that presents formation of new bone similar to control group 40 , the bacterial cellulose membrane bellow of the control group in 1 month and above until five times its area in 2 months 36 and the PLGA membrane, with no differences compared to control group at 2 months 45 , showing that the performance of these implantable devices can vary greatly, depending on the type and duration of treatment.…”

“…In general, Bio-Gide and Jason are membranes that present a good pattern of non-irritation, considering the inflammatory and repair response 51 . Regarding the tissue dynamics involved, the lower presence of inflammatory cells and twice the number of blood vessels in the first fifteen days after implant of Bio-Gide can explain its better performance in comparison to bacterial cellulose membranes, polycaprolactone with 5% hydroxyapatite, Jason and Collprotect [36][37][38] . Bio-Gide also outnumbered blood vessels up to 21 days in relation to bovine membrane Lyostypt 48 .…”

In Vivo Evaluation of Permeable and Impermeable Membranes for Guided Bone Regeneration

“…It consists of using a membrane as a barrier that may or may not be associated with substitute biomaterials over a defect before primary closure to control tissue growth. This technique has been used for decades and aims to allow the cellular neoformation of the desired tissue, preventing the development of other undesirable cell types [ 10 , 17 , 28 , 29 ]. For the application of the concept of GBR, the membrane must be positioned in place and left for a period to ensure space for bone repair and avoid the invasion of connective tissue into the area [ 30 , 31 ].…”