Chemical, Clinical and Histomorphometric Comparison between Equine Bone Manufactured through Enzymatic Antigen-Elimination and Bovine Bone Made Non-Antigenic Using a High-Temperature Process in Post-Extractive Socket Grafting. A Comparative Retrospective Clinical Study

Abstract

Enzyme-deantigenic equine bone (EDEB) and anorganic bovine bone (ABB) are two xenografts made non-antigenic through different processing methods. This study aimed to characterize them for the presence of native bone collagen and other proteins and to compare their histomorphometric outcome when they were used to graft post-extractive sockets. The records of 46 patients treated with EDEB (n = 22) or ABB (n = 24) and followed-up for at least four months after delayed implant placement, were retrospectively collected. Samples of EDEB and ABB were analyzed using Attenuated Total Reflection Fourier Transform Infrared and Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis for the presence of collagen and other proteins. For histomorphometric analysis on bone specimens, newly formed bone and residual biomaterial percentages were calculated. Results of the present study show that EDEB contains type I bone collagen in its native conformation, while no proteins were detected in ABB. Grafting EDEB resulted in a significantly greater quantity of newly formed bone and less residual biomaterial. Our findings suggest that the manufacturing process can greatly affect the graft behavior and a process preserving collagen in its native form may favor bone tissue regeneration.

A New Anorganic Equine Bone Substitute for Oral Surgery: Structural Characterization and Regenerative Potential

“…Altogether, these findings confirm that the biophysical features of AEB are in agreement with that of the xenogeneic bone substitutes treated with high temperature and already described in literature [ 42 ]. Thus, one can expect a similar effectiveness in the repair of bone defects.…”

“…To confirm the chemical composition of AEB, FT-IR analysis was performed, showing the bands associated with the chemical group of hydroxyapatite. The data analyzed showed the presence of phosphate ions at 1019 cm −1 and of the carbonate group at 1418 cm −1 and 875 cm −1 , in agreement with the literature describing the heat treatment output of xenogeneic bone substitutes [ 42 ]. The same bands were detected for ABB.…”

A retrospective preliminary histomorphometric and clinical investigation on sinus augmentation using enzyme-deantigenic, collagen-preserving equine bone granules and plasma rich in growth factors

“…Current published evidence on using PRGF in sinus augmentation does not answer the question if the mixture may accelerate bone formation in the early stages after grafting, and if, accordingly, implant insertion could be carried out earlier; this should be the subject of appropriately designed prospective studies. Such advantage might be of a certain importance when the bone substitute being grafted is known to undergo slow remodeling, as with anorganic bovine bone [18,19]. Concerning EDEB, previous findings [20] show that it already allows early bone formation, to such extent that NFB in biopsies collected 3-5 months after grafting is not significantly different from that of biopsies collected later, up to 12 months from grafting.…”

“…The measurement will be repeated at the mesial side, and the two will be averaged. The MBL will be calculated as the difference between this averaged value and that measured repeating the whole procedure on the corresponding immediate post-insertion intraoral radiograph 18). Concerning the few split-mouth studies published at present comparing anorganic bovine bone alone to its mixture with PRGF, Anitua et al [40] reported anecdotic data concerning two patients whose NFB, in their sinuses grafted with the mixture was similar to that observed, in other studies, when sinuses are grafted with anorganic bone alone and, surprisingly, it was much lower when anorganic bovine bone was grafted alone (21.4% vs. 8.4% and 28.4% vs. 8.2%).…”

“…An alternative process based on using lytic enzymes working at lower temperatures (about 37°C) is applied to manufacture enzyme-deantigenic equine bone (EDEB). This process, that involves selective degradation of antigens, allows preserving type I bone collagen intact [18]. Such EDEB feature was claimed to explain the greater amount of newly formed bone that could be observed when sinuses [18][19][20] and post-extraction sockets [18] were grafted with EDEB, compared to anorganic bovine bone, possibly for a different rate of osteoclast adhesion on the two biomaterials [21,22].…”