Fresh-Frozen Bone Allografts in Maxillary Ridge Augmentation: Histologic Analysis

Abstract

Bone allograft has become an alternative to autogenous bone due to its decreased operative trauma and the almost unlimited supply of reconstructive material. The aim of the present study was to histologically evaluate the suitability of fresh-frozen bone graft (test group) used in maxillary ridge augmentation, comparing it to autogenous bone (native maxilla: control group). During the re-entry procedures, 9 months after the fresh-frozen allogeneic bone blocks were placed in the atrophic maxillary ridges, bone cores were removed with a trephine bur from test and control treatments in the same patient. Routine histologic processing using hematoxylin and eosin and Picrosirius staining was performed. Mature and immature collagen area and density analysis were carried out for both groups under polarization. The results of Student's t test for paired samples (P > .05) showed no statistically significant difference in mature and immature collagen area or density percentage between test and control groups. Histologically similar bone formation patterns were observed in both groups. We concluded that fresh-frozen bone allograft is a biologically acceptable alternative for augmentation of the deficient alveolar ridge, showing a similar collagen pattern to that of autogenous bone.

Thermal processing of bone: in vitro response of mesenchymal cells to bone-conditioned medium

“…The most commonly used thermal processing methods for bone grafts are autoclaving, 7-15 pasteurization, 17-21 and freezing. 22,23 This study is a logical extension of previous studies done by this group, describing the paracrine-like function of bone chips in vitro -bone chips that were freshly prepared and thus represent experimental autografts. [2][3][4] The autoclaving, pasteurization, and freezing of bone is not restricted to autografts and IL-11, interleukin 11; NOX4, NADPH oxidase 4; PRG4, proteoglycan 4. a Relative mRNA levels (mean AE standard deviation) of the indicated genes when cells were incubated for different periods of time.…”

“…Fresh frozen bone has been used for sinus floor elevation. 22,23 Fresh frozen bone is harvested from human cadavers, then processed immediately and stored. Fresh frozen bone promotes bone formation during implant osseointegration.…”

Maxillary Ridge Augmentation with Custom-Made CAD/CAM Scaffolds. A 1-Year Prospective Study on 10 Patients

“…12-14 A variety of bone substitutes-such as allogeneic, xenogenic, and synthetic materials-as well as combinations of these are currently available for ridge augmentation. 7,[15][16][17][18] An ideal bone substitute should be able to regenerate complex 3D anatomical defects while possessing mechanical properties similar to the native structures, allowing for function and load bearing. It should be biocompatible and, ideally, bioresorbable.…”

“…15 The characteristics of ideal bone substitutes are as follows: They should show biocompatibility, have excellent osteoconductive properties and appropriate strength, and they should be able to be formed into a suitable shape easily and ultimately replace the bone completely within a short period. 15 Prepared allogeneic or xenogenic materials have been successfully used for ridge augmentation 7,16,17 and, more recently, biologically inert alloplastic scaffolds have been shown to offer a reasonable alternative. 18 Porous hydroxyapatite (HA) ceramics have been used extensively as substitutes in bone grafts because the crystalline phase of natural bone is HA.…”

“…18 For optimal bone regeneration, scaffolds need to fit anatomically into the requisite bone defects and, ideally, promote cell growth and differentiation. [16][17][18] For this reason, there is a clinical need for anatomically shaped biomaterials to repair voids of bone loss in bone defects. [19][20][21] Current implant procedures typically require bone replacement materials to be manually cut, shaped, and formed at the time of implantation, resulting in an expensive and time-consuming process.…”