Demineralized Freeze-dried Bone Research Articles

Platelet-Rich Fibrin-Enhanced Bone Healing Co-grafted With Either Hydroxyapatite and Beta Tricalcium Phosphate or Demineralized Freeze-Dried Bone in Small Maxillofacial Osseous Defects: A Clinical Comparison.

This study was conducted to clinically compare a commercially available combination of 70:30 nanocrystalline hydroxyapatite (HA) and beta tricalcium phosphate (βTCP) along with platelet-rich fibrin (PRF) with demineralized freeze-dried bone (DFDB) grafts along with PRF in small maxillofacial osseous defects. Thirty patients with one osseous defectwere randomly distributed into two groups of 15 each: Group A and Group B. Group A patients received HA+βTCP+PRF while Group B received DFDB + PRF. Postoperative pain, swelling, wound dehiscence, and the presence or absence of infection were evaluated at various intervals up to seven postop days and compared between the two groups and within either group. A technetium 99m methylene diphosphonate (MDP 99mTc) scan was also done for a representative patient of either group at the end of three months to evaluate the fate of the graft. We found no significant difference between the two groups for any of our parameters. Significant improvements were noted for pain and swelling within either group at various intervals. The MDP 99mTc scan showed increased tracer uptake for the representing patient of either group. HA+βTCPis more inexpensive than DFDB and more readily availableand has no host incompatibility or infection potential, resulting in similar clinical postoperative states as DFDB when either is used with PRF.

Histologic Analysis of a Novel Extracellullar Matrix Membrane for Guided Bone Regeneration: An Experimental Study in Rabbits

This experiment was conducted to study the histologic feasibility and biologic impact of Ti02 impregnation of an extracellullar matrix (ECM) membrane in guided bone regeneration. Eighteen adult New Zealand White rabbits were used. Bilateral bone defects were created in edentulous areas of the maxilla. The defects were filled with demineralized freeze-dried bone (DFDB). ECM was randomly pretreated with a suspension containing saline and 3 mg Ti02 granules. A regular ECM membrane served as a control on the contralateral side. Healing periods were 2, 4, and 8 weeks. Histologic and histomorphometric analyses were performed. The parameters assessed were (1) zone of inflammatory cells adjacent to ECM membrane, (2) presence of cellullar ingrowth into ECM, and (3) presence of Ti02 particles within the ECM barrier membrane. In general, no adverse reactions toward both groups of ECM membranes could be noted. The Ti02 particles remained within the ECM after 8 weeks of healing, making histologic detection of ECM easy. Histomorphometric analysis revealed low numbers of inflammatory cells adjacent to the ECM surface and adequate preservation and integration of the barrier. Contrasting Ti02 particles impregnated into the ECM membrane can be a very useful tool for the detection of similar biologic materials in in vivo models.

A Novel Approach for Treatment of an Unusual Presentation of Radicular Cysts Using Autologous Periosteum and Platelet-Rich Fibrin in Combination with Demineralized Freeze-Dried Bone Allograft

Radicular cysts are the most common cystic lesions affecting the jaws. They are most commonly found at the apices of the involved teeth. This condition is usually asymptomatic but can result in a slow-growth tumefaction in the affected region. The following case report presents the successful treatment of radicular cysts using autologous periosteum and platelet-rich fibrin with demineralized freeze-dried bone allograft.

Iliac Crest Autogenous Bone Graft versus Alloplastic Graft and Guided Bone Regeneration in the Reconstruction of Atrophic Maxillae: A 5-Year Retrospective Study on Cost-Effectiveness and Clinical Outcome

Reconstruction of the atrophic maxillae with autogenous bone graft and jawbone-anchored bridges is a well-proven technique. However, the morbidity associated with the concept should not be neglected. Furthermore, the costs for such treatment, including general anesthesia and hospital stay, are significant. Little data are found in the literature with regard to a cost-benefit approach to various treatment alternates. The aim of this retrospective study was to compare from a health-economical and clinical perspective the reconstruction of the atrophic maxillae prior to oral implant treatment either with autogenous bone grafts harvested from the iliac crest or the use of demineralized freeze-dried bone (DFDB) in combination with a thermoplastic carrier (Regeneration Technologies Inc., Alachua, FL, USA) and guided bone regeneration (GBR). A total of 26 patients (13 + 13) were selected and matched with regard to indication, sex, and age. The study was performed 5 years after the completion of the treatment. Implant survival, morbidity, and complications were analyzed. Furthermore, a detailed analysis of the total cost for the respective treatment modality was performed, including material, costs for staff, sick leave, etc. The study revealed no statistical difference with regard to implant survival for the respective groups. The average total cost, per patient, for the DFDB group was 22.5% of the total cost for a patient treated with autogenous bone grafting procedures. The study concluded that reconstruction of atrophic maxillae with a bone substitute material (DFDB) in combination with GBR can be performed with an equal treatment outcome and with less resources and a significant reduced cost in selected cases compared with autogenous bone grafts from the iliac crest.

Improvement in the osteoblastic cellular response to a commercial collagen membrane and demineralized freeze-dried bone by an amino acid derivative: an in vitro study

The objectives of this in vitro study were (1) to determine whether a commercially available collagen membrane (CM) or human demineralized freeze-dried bone (DFDB) particles adversely affected viability or function in cultured osteoblasts through oxidative stress, and, if so, (2) to determine whether N-acetyl cysteine (NAC) successfully prevented loss of viability and dysfunction in osteoblasts. Rat calvaria-derived osteoblasts were seeded onto polystyrene and commercially available CM (Cytoplast ®) or DFDB (DynaGraft ™) with or without pretreatment with NAC solution. The osteoblastic response was evaluated using a flow cytometric cell viability assay, measurement of attached viable cell number, quantification of reactive oxygen species (ROS) and alkaline phosphatase (ALP) staining. The percentage of viable cells on CM was <50% at 24 h after seeding. However, this increased to 70% by pretreatment with NAC. The numbers of attached osteoblasts on DFDB remained at 60% the level of that on polystyrene at 24 h after seeding, but increased to up to 90% the level of that on polystyrene with NAC pretreatment. Although collagen materials increased intracellular ROS generation 1.5-5 times that with polystyrene, this was significantly reduced by NAC pretreatment. The percentage of the ALP-positive area was consistently 7% or less on CM and DFDB at days 7 and 14, which was restored by NAC pretreatment up to 60% or more. Commercially available CM and DFDB impaired osteoblastic viability and function and markedly increased intracellular ROS, indicating an oxidative stress-mediated negative impact on osteoblasts. Pretreatment with NAC substantially alleviated these cytotoxic effects.

Effect of systemic parathyroid hormone (1–34) and a β‐tricalcium phosphate biomaterial on local bone formation in a critical‐size rat calvarial defect model

The objective of this study was to evaluate local bone formation following systemic administration of parathyroid hormone (1-34) (PTH), a surgically implanted synthetic beta-tricalcium phosphate (beta-TCP) bone biomaterial serving as a matrix to support new bone formation. Critical-size, 8 mm, calvarial through-and-through osteotomy defects were surgically created in 100 adult male Sprague-Dawley rats. The animals were randomized into five groups of 20 animals each to receive one of the following treatments: PTH (15 microg PTH/kg/day; subcutaneously), PTH/beta-TCP, beta-TCP, or particulate human demineralized freeze-dried bone (DFDB), and sham-surgery controls. Ten animals/group were euthanized at 4 and 8 weeks post-surgery for radiographic and histometric analysis. The histometric analysis showed that systemic PTH significantly enhanced local bone formation, bone fill averaging (+/-SE) 32.2+/-4.0% compared with PTH/beta-TCP (15.7+/-2.4%), beta-TCP (12.5+/-2.3%), DFDB (14.5+/-2.3%), and sham-surgery control (10.0+/-1.5%) at 4 weeks (p<0.014). Systemic PTH showed significantly enhanced bone formation (41.5+/-4.0%) compared with PTH/beta-TCP (22.4+/-3.0%), beta-TCP (21.3+/-4.4%), and with the sham-surgery control (23.8+/-4.2%) at 8 weeks (p<0.025). The DFDB group showed significantly increased bone formation from 4 (14.5+/-2.3%) to 8 weeks (32.0+/-3.2%) (p<0.006). The PTH/beta-TCP and beta-TCP groups both showed limited biomaterials resorption. The radiographic analysis was not diagnostic to distinguish local bone formation from the radiopaque beta-TCP biomaterial. Systemic administration of PTH significantly stimulates local bone formation. Bone formation was significantly limited by the beta-TCP biomaterial.

A histomorphometric study on collagen-apatite composite as a graft material: the influence of gap size at the titanium–bone interface in animal model

The purpose of this study was to evaluate the healing process of collagen-apatite composite (CAC) at the titanium-bone interface in animal model. Small gaps (0.5 or 1.0 mm-sized wells) were prepared in the epoxy-resin block implants coated with pure titanium. The gaps were filled with CAC or demineralized freeze-dried bone (DFDB). The titanium-coated epoxy-resin block implants were inserted in the tibia of rabbit for 4 weeks or 8 weeks. The microscopic features of bony healing process in the grafted gaps were examined and analyzed. In the histomorphometric analysis, CAC group showed higher fraction of newly-formed bone than DFDB group in both 0.5 and 1.0 mm gap subgroup at 4-week specimen (P < 0.05). In the transmission electron microscopic examinations, osteoblasts of the newly-formed bone of CAC group showed more cellular activity than that of DFDB group. From the results, it was expected that CAC had more beneficial property on early bony healing process than DFDB at the titanium-bone interface.

Influence of Matrix-Suspended Demineralized Bone on Osseous Repair Using a Critical-Sized Defect in the Rat (Rattus norvegicus) Calvarium

Demineralized freeze-dried bone (DFDB) in matrix form must be rehydrated with a carrier medium which allows for easy manipulation during periodontal surgery. The purpose of this study was to evaluate how human DFDB suspended in a polyol matrix affects new bone formation in the rat calvarium critical-sized defect (CSD) model. Fifty-five adult male Harlan Sprague-Dawley rats were assigned to 1 of 5 treatment groups: polyol, 100% DFDB, 47% DFDB/polyol, 47% DFDB, or an unfilled control. They were then placed into 8-m calvarial CSDs. The bone donor source company for the DFDB and DFDB/polyol groups was the same. Calvaria were harvested 10 weeks after surgery and evaluated histomorphometrically. The diameter of bone particles from the 3 groups containing DFDB was measured by scanning electron microscopy. There was no statistically significant difference in the percentage of bone fill between any of the groups, although the 100% DFDB group exhibited the most bone fill. The 47% DFDB/polyol and 47% DFDB groups had similar amounts of bone formation. The average size of the demineralized bone particles from the 100% DFDB group was significantly smaller than that of the other 2 groups containing DFDB. Adding a polyol to DFDB produced similar osseous regeneration in the rat calvarium defect model vs DFDB alone. Yet from a clinical standpoint, the polyol enhanced graft handling and stability. Graft particle size may have an effect on bone fill.

Effect of a Hydroxyapatite Tricalcium Phosphate Alloplast on Osseous Repair in the Rat Calvarium

Bony defects caused by periodontitis are often treated by regenerative therapy using autografts and/or allografts. Alloplasts, such as hydroxyapatite or ceramics, are also used as osteoconductive materials that serve as a scaffold for new bony ingrowth. The purpose of this study was to determine the effect of hydroxyapatite tricalcium phosphate (HA-TCP) on osseous repair in the rat calvarium. Forty-four adult male Harlan Sprague-Dawley rats were assigned to one of four treatment groups: HA-TCP macroporous disk, HA-TCP microporous disk, HA-TCP granules, and demineralized freeze-dried bone (DFDB). The materials were placed into 8-mm calvarial critical-size defects (CSD). Calvariae were harvested at 10 weeks post-surgery and evaluated histomorphometrically. The DFDB group had significantly (P <0.05) more new bone formation (47%) than any other group. The HA-TCP macroporous disk group had significantly (P <0.05) more new bone formation (19.7%) than the HA-TCP microporous disk (8.5%) or HA-TCP granule (6.9%) groups. The HA-TCP macroporous disk may elicit significant new bone formation due to its rigid space-maintaining scaffold and pore size for vascular ingrowth. It is well tolerated by host tissues and may be a suitable carrier for growth factors.

A comparative study of barrier membranes as graft protectors in the treatment of localized bone defects. An experimental study in a canine model.

Guided bone regeneration is a predictable and well-documented surgical approach for the treatment of deficient alveolar ridges prior to endosseous implant placement. The purpose of this study was to compare a new resorbable membrane (GORE RESOLUT ADAPT Regenerative Membrane, i.e. 67% glycolide (PGA) : 33% trimethyline carbonate (TMC)) with Bio-Gide, a resorbable collagen membrane. Five canines were used in the study. Three saddle-type osseous defects were created bilaterally in edentulous areas of the mandible. The defects were filled with assayed, canine demineralized freeze-dried bone (DFDB) in a thermoplastic gelatin matrix. Using a randomized block design, four sites were covered with PGA : TMC membranes of four different porosities, one site was covered with a collagen membrane and one site consisted of DFDB alone (control). At 3 months, the animals were euthanized and the mandibles were removed en bloc for laboratory processing. A total of 30 sites were reviewed microradiographically and underwent histomorphometric analysis for bone regeneration, soft tissue presence and remaining graft material. All sites exhibited uneventful healing. A significantly higher percentage of bone regeneration was seen in the sites protected by the PGA : TMC membrane. A higher component of soft tissue was visible beneath the collagen membrane as compared with the PGA : TMC membrane. The control sites exhibited noticeable deformation of the regenerated bone secondary to collapse of the overlying periosteum. The authors conclude that the PGA : TMC membrane protected the DFDB-filled defect and allowed a greater amount of bone regeneration than the defect protected by the collagen membrane or the control.

Better research needed for implants in grafted maxillary sinuses

Objectives To evaluate the survival of the implants placed into various materials used in the maxillary sinus lift procedure. The materials were autogenous bone hydroxyapatite (HA) alone or in combination with autogenous bone or demineralized freeze-dried bone (DFDB). Data sources Medline computer search of the English literature between 1980 and 1996. Study selection Only 10 of 28 identified studies met the inclusion criteria of >10 patients in each study all receiving root form endosseous implants, <5% loss in follow-up over 6 months and reporting of survival data of the implants. Data extraction and synthesis Proportion of surviving implants calculated with 95% confidence intervals. Patients were followed up for up to 60 months. Results Conclusions These studies suggest that implant survival rates were similar for autogenous bone, HA/autogenous bone mix, HA/DFDB, and HA alone.

Bone tissue reactions to demineralized freeze-dried bone in conjunction with e-PTFE barrier membranes in man.

Demineralized freeze-dried bone (DFDB) has been demonstrated to be osteoinductive in rodents, while no new bone formation has been reported at ectopic sites in goats, dogs and monkeys. In the present study, DFDB was used in connection with dental implant placement and expanded polytetrafluorethylene (e-PTFE) membranes. Histological examination showed that DFDB particles near the host bone underwent a partial remineralization, while DFDB distant from pre-existing bone was slowly resorbed and showed no remineralization, no osteoinduction, and no osteoconduction. This could be due either to the fact that the response to osteoinductive stimuli is lower in higher species, or to the fact that large quantities of DFDB are required to provide sufficient quantities of bone morphogenetic protein.

A Preliminary Study of the Osteogenic Potential of a Biodegradable Alloplastic-Osteoinductive Alloimplant

A biodegradable copolymer of polylactide-polyglycolide was combined with allogeneic demineralized freeze-dried bone (DFDB) and implanted into 15-mm diameter defects in the calvaria of 26 New Zealand White rabbits. Similar defects were created in the calvaria of another 26 rabbits. These animals served as controls and did not receive copolymer implants. Upon sacrifice, both the implants and the controls were evaluated clinically, roentgenographically, and histomorphometrically using a Zeiss Image Analysis System (Videoplan, version 4.1). Both controls and implants were evaluated in groups at four, eight, 12, 16, 20, and 24 weeks. When compared with the control defects, the copolymer-DFDB implants displayed a significantly greater volume of trabecular bone. Three of the 15-mm diameter defects displayed evidence of complete osseous bridging at eight weeks. No adverse host-tissue responses were observed histologically in any of the implant specimens.