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Regeneration and reconstruction of segmental bone defects (SBD) is a clinical challenge in maxillofacial surgery and orthopedics. The present study evaluated efficacy of guided bone-regeneration (GBR) of rat femoral SBD using osteoconductive equine-bone (EB) and beta-tricalcium phosphate (beta-TCP) grafts, either with or without platelet-derived growth-factor (PDGF). Following ethical-approval, 50 male Wistar-Albino rats (aged ~12–15 months and weighing ~450–500 g) were included. A 5 mm femoral critical-size SBD was created and animals were divided into five groups depending on the graft material used for GBR (EB, EB + PDGF, Autograft, beta-TCP, beta-TCP + PDGF; n = 10/group). Following 12-weeks of healing, animals were sacrificed and femur specimens were analyzed through qualitative histology and quantitative histomorphometry. There was new bone bridging femoral SBD in all groups and qualitatively, better bone formation was seen in autograft and EB + PDGF groups. Histomorphometric bone-area (BA %) was significantly high in autograft group, followed by EB + PDGF, beta-TCP + PDGF, EB, and beta-TCP groups. Addition of PDGF to EB and beta-TCP during GBR resulted in significantly higher BA%. After 12-weeks of healing, EB + PDGF for GBR of rat femoral segmental defects resulted in new bone formation similar to that of autograft. Based on this study, GBR with EB and adjunct PDGF could be a potential clinical alternative for reconstruction and regeneration of segmental bone defects.

International audience; Sinus elevation is a common procedure to increase bone volume in the atrophic maxilla to allow placement of dental implants. Autogenous bone is the gold standard but is limited in quantity and causes morbidity at the donor site. β-TCP is a synthetic biomaterial commonly used in that purpose. It appears to induce a poor inflammatory response. This study aimed to evaluate the degree of edema of the sinus mucosa after sinus lift surgery according to the type of biomaterial. Forty sinuses (20 patients) were included retrospectively and divided into 2 groups according to the biomaterial that was used: synthetic biomaterial (BTCP group), natural bone (BONE group). A control group (CTRL group) was constituted by the non-grafted maxillary sinuses. Twelve measurements per sinus were realized on pre- and post-operative computed tomography and averaged to provide the sinus membrane thickness value (SM.Th). SM.Th was thicker post-operatively in the BTCP and BONE groups in comparison with the CTRL group and in comparison with pre-operative measurements. No difference was found post operatively between the BTCP and BONE groups. We found that a synthetic biomaterial (β-TCP) induced the same degree of edema, and thus of inflammation, as natural bone. It constitutes therefore an interesting alternative to autogenous bone for maxillary sinus lifts.

International audience; A casting method based on ceramic slurry ice-templating was used to create beta-tricalcium phosphate anisotropic oriented macroporous scaffolds. The freeze-casting method produces tubular interconnected pores with ellipsoidal shape. The tubular porosity structure is supposed to enhance cell invasion. Several samples with pore size ranging from 50 μm to 350 μm and porosity from 30% to 70% were synthesized using different processing parameters: dry matter and binder content of slurry and freezing rate. The osteoblastic cell colonisation into these samples was compared to that into classical scaffolds obtained from ceramic slurry impregnation of organic skeleton which allows the development of isotropic spherical porous structure with 250 to 600 μm pore diameter size. The analysis by scanning electron microscopy of cell invaded samples shows that the size of the pores of the ice-templated scaffolds is sufficiently large to enable fast osteoblastic cell colonisation.

The purpose of this study was to evaluate the effect of porcine cancellous bone as a scaffold in a rat calvarial defect model. Critical-sized defects were created in 30 male Sprague-Dawley rats. The animals were divided into critical defect (CD, n=10), -tricalcium phosphate (TCP) graft (BT, n=10) and porcine cancellous bone graft (PCB, n=10) groups. Each defect was filled with -TCP mixed with fibrin glue or porcine cancellous bone powder mixed with fibrin glue. In the CD group, the defect was left empty. All rats were sacrificed at 8 weeks after bone graft surgery, and bone formation was evaluated by gross observation, plain radiography, micro-computed tomography scanning and histological evaluation. Repair of bone defect was the least in the CD group, and significant new bone formation was observed in the PCB group. Grafting of porcine cancellous bone was more efficient for regenerating new bone than grafting -TCP.

Contains fulltext : 88778.pdf (Publisher’s version ) (Closed access) Alveolar reconstruction of bony defects in cleft lip and palate patients is a widely accepted treatment regimen for which multiple donor sites can be used. For 25 years, autogeneous bicortical mandibular symphyseal bone grafts have been used at the authors' centre. In cases in which the alveolar defect was too large to match the volume of the mandibular symphyseal bone transplant, beta-TCP granules were packed against the bone transplant to fill the defect completely. In a retrospective study, 18 patients, who were treated with mandibular symphyseal bone wrapped in beta-TCP granules, were compared with 29 patients, who were treated with mandibular symphyseal bone only. To assess alveolar height, occlusal radiographs were taken directly postoperatively and 1 year later. Mean alveolar bone loss was calculated and compared between groups using Student's t-test and linear regression analysis. No statistically significant difference in alveolar height was found between the two groups. It was concluded that mandibular symphyseal bone grafts enriched with beta-TCP granules can be used successfully in cases in which the alveolar cleft is too large to be grafted with mandibular symphyseal bone alone. 01 mei 2010

A resorbable composite material (40% PLLA and 60% beta TCP) with a high breaking strength and capacity to withstand plastic and elastic strain has been developed for cervical interbody fusion. This is a prospective study to evaluate clinical and radiological results of 20 patients implanted with 27 cages (mean follow-up, 27 months). Clinical (neck disability index, VAS, neurological evaluation) and radiological (anteroposterior, lateral, bending X-rays) data were assessed before and after surgery. At the end of the study, CT scan was performed to evaluate fusion, resorption of the cage and density of the new tissue substituting the cage. The mean patient age was 50.3 years (range, 18-79 years). The average improvement was 55% for neck pain, 83% for arm pain and 65% for NDI, with 85% good or excellent results at final outcomes. Radiologically, lordosis was significantly improved (mean gain of 5.4 degrees and 3.7 degrees for overall and segmental lordosis, respectively). This correction was conserved in 95% of cases. Fusion was obtained in 96% (CT evaluation). Resorption was started in all cases and completed in an average of 36 months after surgery. The mean density of tissue substituting the cage was 659 UH with a range, of 455-911 UH (compatible with bone nature). Over time, the amount of bony tissue increased and the graft remodelled with an increase in density value. This demonstrates a biological activity and changing bone mineral content of this tissue. The new composite cage under investigation provides long-term fusion without loss of correction or inflammatory reaction. The ceramic block guarantees the maintenance of the disc height and its slow resorption allows long-term fusion and stability with good and reliable clinical and radiological outcomes.

STUDY DESIGN The efficacy of tricalcium phosphate and hydroxyapatite (beta-TCP/HA) grafts was studied after anterior cervical discectomy (ACD). OBJECTIVE This study presents our observations about the efficacy of beta-TCP/HA grafts after ACD. SUMMARY OF BACKGROUND DATA Especially in the last 2 decades, fusion materials such as autograft and allograft, as well as different kind of cages were used to maintain fusion after ACD. METHODS beta-TCP/HA grafts after ACD were used in 17 patients. The cervical and radicular pain was evaluated via visual analog scale (VAS) score preoperatively, at postoperative third week, and after 20 months (range: 18 to 24 mo) after the operation. The radiologic evaluations were done preoperatively, at postoperative first day and at the latest follow-up. The VAS, intervertebral space ratio, height of intervertebral disc space and neural foramen, and cervical and segmental lordosis angles were recorded preoperatively and during the postoperative follow-up period. The presence of fusion was controlled in computed tomography scans taken at the latest follow-up. RESULTS Both clinical and radiologic evaluations yielded satisfactory results. VAS scores decreased significantly in all patients. The intervertebral space and neural foramen and intervertebral disc heights increased at postoperative day 1 but were found to be decreased at the latest follow-up (P

A recombinant BMP-2-retaining putty-form implant in combination with a hip prosthesis was used to reconstruct a canine hip joint with defects similar to those encountered in revision total hip arthroplasty (THA). The bone defects were made by resecting the medial half of the proximal femur and the superior acetabular bone with inner iliac wall perforation in 10 dogs. In five dogs, hip prostheses were implanted with the putty material consisting of a synthetic polymer (poly D,L-lactic acid-polyethylene glycol block copolymer), β-tricalcium phosphate powder, and recombinant human BMP-2 in each defect (BMP/Polymer/TCP group). In the remaining five dogs, the same material without rhBMP-2 (control group) was implanted. In the BMP/Polymer/TCP group, new radiopaque shadows began to appear 4 weeks after surgery at the defects around the hip prostheses on both the femoral and acetabular sides. At 12 weeks, the defects were completely filled with new bone in contact with the prosthesis. On histology, the rhBMP-2/Polymer/β-TCP composite putty implants had been completely resorbed and replaced by new bone. Repair of the bone defects was not seen in the control group. The ability of this material to restore bone effectively eliminates the dependency on bone grafts of autogeneic or allogeneic origin for revision hip arthroplasty and thus opens up a potential new treatment approach in hip cases requiring this type of surgery. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1042–1051, 2007

Beta-tricalcium phosphate/carboxymethyl chitin composites [TCP/CMCh] of various ratios of TCP granules and CMCh were made and their mechanical properties, handling properties and repair performance for bone defects and for osteochondral defects were investigated. Water pooling ratio of CMCh was approximately 40 times the weight itself. TCP/CMCh of a higher TCP ratio had higher stress at 50%-strain. The stress at 50%-strain of TCP/CMCh with 0, 2.5, 5.0, 7.5, 10 TCP ratios was 0.12, 0.51, 1.08, 1.46, 1.67 (MPa, n=5), respectively. The TCP/CMCh with 5.0 TCP ratios had the best total scores in handling tests. The bone repair rate of TCP/CMCh was TCP ratio 2.5< Blank= TCP ratio 7.5< TCP ratio 5.0. In the implantation test for osteochondral defects, TCP/CMCh was completely absorbed at four weeks after surgery. Regeneration of the articular cartilage was seen with TCP/CMCh and HA/CMCh but not with TCP granules, which remained eight weeks after implantation. The regenerated articular cartilage had remained 32 weeks after implantation. In conclusion, it was demonstrated that this TCP/CMCh composite was a promising material for repairing osteochondral defects.

The aim of the study was to investigate the biocompatibility, degradation, and biomechanical properties of beta-TCP (Cerasorb) in a weight-bearing sheep model. beta-TCP implant prototypes were implanted in the tibial head of adult merino sheep. After 6 and 12 months material explants were harvested for biomechanical, histological, and histomorphometrical analysis. Corresponding bone specimens of the intact bone of the contralateral leg were used as controls in the biomechanical test. Compression tests showed higher values for maximum fracture load, yield strength, and compression modulus after 6 and 12 months compared to control. Microscopically, the implants showed good osteoconduction and were incorporated into the bone; however, relevant amounts of beta-TCP were still present after 12 months. Histomorphological results revealed that beta-TCP had partially degraded between implantation and 6 months, but its share remained constant between 6 and 12 months. The bone volume fraction in the area of the implant (46% +/- 6.5%) was initially higher than in the corresponding bone area of the contralateral leg (31% +/- 9.6%), but after 12 months declined to 29% +/- 9.4% (control: 33% +/- 8.3%), while the share of beta-TCP remained constant at 36% +/- 12.2%. These findings were supported by microradiographic data. In conclusion, in a weight bearing implantation model beta-TCP showed good biocompatibility, osseointegration and beginning degradation, even though it was not further degraded between 6 and 12 months.

Objective. The aim of this investigation was to examine the bone regenerative potential of newly biphasic calcium phosphate ceramics (HA-β-TCP 30/70), by assessing histological and histomorphometric results of human specimens retrieved from sinuses augmented with HA-β-TCP 30/70, and comparing them to anorganic bovine bone (ABB), mineralized solvent-dehydrated bone allograft (MSDBA), and equine bone (EB), after a healing period of 6 months.Materials and Methods. Four consecutive patients with edentulous atrophic posterior maxilla were included in this report. A two-stage procedure was carried out for sinus augmentation with HA-β-TCP 30/70, ABB, MSDBA, and EB. After 6 months, specimens were retrieved at the time of implant placement and processed for histological and histomorphometric analyses.Results. At histological examination, all biomaterials were in close contact with the newly formed bone and showed the same pattern of bone formation; the grafted granules were surrounded by a bridge-like network of newly formed bone. A limited number of ABB particles were partially covered by connective tissue. The histomorphometric analysis revealed 30.2% newly formed bone for Ha-β-TCP 30/70, 20.1% for ABB, 16.4% for MSDBA, and 21.9% for EB.Conclusions. Within the limitations of the present investigation, these results support the successful use of HA-β-TCP 30/70 for sinus augmentation.

Beta-tricalcium phosphate (β-TCP) is a synthetic bone substitute having high porosity and fast resorption. This retrospective study aimed at evaluating the effectiveness of an highly macroporous β-TCP for maxillary sinus floor augmentation.Twenty-seven consecutive patients (17 woman/10 men, mean age: 59.7 years) in 2 clinics underwent maxillary sinus augmentation by lateral approach using β-TCP as grafting material. Implant survival, prosthesis success, periimplant bone loss, oral hygiene level, soft tissue condition, complication occurrence, and patient satisfaction were assessed.Thirty-one sinuses were successfully augmented. Sixty implants were placed. No sinus membrane perforations occurred. The mean follow-up after grafting was 39.3 ± 8.7 months (range, 22-52 months), and it was 30.5 ± 8.1 months (range, 15-43 months) after implant loading. No implants were lost. After 1 year of loading, marginal bone loss averaged -0.88 ± 0.46 mm (n = 54 implants). Mean full-mouth plaque and bleeding scores were 11.5% ± 4.8% and 3.5% ± 2.8%, respectively. No biological or mechanical complications were recorded. Patient satisfaction was very high.Despite limited sample size and follow-up duration, highly macroporous β-TCP proved a valuable bone substitute for sinus augmentation, even when used alone.

In the quest for bioinert adaptable alloplastic materials, TCP ceramics have gained a new application in craniofacial bone substitutes. Therefore, a histomorphological, intraindividual, comparative study was conducted on seven adult Goettingen miniature pigs (GMP) to analyze the difference of the degradation and remodelling processes of alpha-TCP and beta-TCP in critical size defects of the proximal tibiae. In addition, primary insertion of dental implants followed to study osseous integration. The critical size defects, which were created in the proximal tibiae in GMPs, were filled on the left side with beta-TCP and on the right side with alpha-TCP. Two GMPs were used as control group. After 4-68 weeks of investigation, the GMPs were sacrificed by narcosis. The histological investigation showed that these ceramics have an osteoconductive effect. It was noted that ossification proceeds centripetally. It could be demonstrated that the degradation of the materials follows a hydrolytical process and that the intratrabecular integrated ceramic remnants follow a dynamic remodelling process. Within 68 weeks after implantation, 90% of the TCP granulae were degraded. Macrophages were found in the marrow space, containing microparticles of TCP, especially after alpha-TCP implantation. In conclusion, defined degradation of these ceramics allows early functional bone regeneration with an additional undisturbed biofunctional unisotrop orientation of new trabeculae. Furthermore, dental implants should be inserted 5-6 months after TCP implantation.

Guided Bone Regeneration (GBR) is a method for bone tissue regeneration. In this method, membranes are used to cover bone defects and to block the invasion of the surrounding soft tissues. It would provide sufficient time for the osteogenic cells from bone marrow to proliferate and form new bony tissues. In spite of the potential usefulness of this method, no appropriate materials for the GBR membrane have been developed. Here we design the ideal mechanical properties of the GBR membranes and created novel materials, which is the composite of beta-tricalcium phosphate (beta-TCP) and block copolymer of L-lactide, glycolide, and epsilon-caplolactone (PLGC). In the animal experiments with the use of the GBR membranes for large bone defects, we observed significant enhancement in the bone regeneration after 12 weeks implantation and proved the effectiveness of the materials.

Beta-tricalcium phosphate (beta-TCP) was grafted into rat mandibular bone defects to assess its potential as a scaffold material for bone regeneration. For this purpose, beta-TCP (TCP), allogenic bone (Allograft), and allogenic bone combined with beta-TCP (Combined) were employed as graft materials. To the left side of the graft materials in the bone defects, platelet-rich plasma (PRP) was added. The rats were sacrificed at one, three, and five weeks. Bone formation rate (BFR), remaining beta-TCP rate (RTR), beta-TCP absorption rate (TAR), whole amount of beta-TCP (WTCP), and total rate of BFR and RTR (TBR) were measured. Combined showed equivalent BFR to Allograft at five weeks, and showed higher RTR at one week and higher BFR at five weeks than TCP. Combined with PRP showed higher TAR than that without PRP at three weeks. Therefore, combination with allogenic bone showed reduced beta-TCP absorption, hence enhancing the role of beta-TCP in bone regeneration. These findings suggested that beta-TCP is a better scaffold for bone regeneration if its early absorption is reduced when used in combination with an osteogenic material.

This study was conducted to histomorphologically determine the quantity of bone formation induced by TAK-778, a 3-benzothiepin derivative, (Takeda Pharmaceutical Co.Ltd.), in various amounts, using b-tricalcium phosphate granules (beta-TCP; OLYMPUS Corp.) as a carrier for the osteogenetic agent.Ten-week-old female SD rats were used. An incision was made over the parietal region of the head. The cranial periosteum was ablated and a titanium tube was fixed with an adhesive resin cement to the central part of the head, through which a mixture of TAK-778 and beta-TCP was implanted under various conditions. Tissue specimens were prepared at 4, 8, and 16 weeks after the implantation for histomorphological examination, and the proportion of new bone formation was compared at fixed time points using the NIH imaging software. The amount of new bone formation was examined every week after the implantation of TAK-778 at various doses, and the mean values were compared using Fisher's PSLD test (P0.05).The histomorphological observations revealed new bone formation in all the groups, irrespective of the amount and the duration of implantation of TAK-778. A comparative study revealed that the amount of new bone formation was the largest at 16 weeks following the implantation of a mixture of beta-TCP and 100 mg of TAK-778.1. The present study confirmed the acceleration of new bone formation soon after TAK-778 implantation. 2. The results suggested that the action of TAK-778 could be maintained over time if the agent was used in combination with beta-TCP. 3. The time-course of bone formation differed depending on the proportion of TAK-778 and beta-TCP in the mixture used. 4. TAK-778 at the dose of 10 mg or 50 mg was more effective than that at the dose of 100 mg for the early formation of new bone. These results indicate that TAK-778 accelerates the formation of new bone and that beta-TCP is a useful carrier for TAK-778.

Autogenous bone transfer is still regarded as the "golden standard" for many indications in oral and cranio-maxillofacial surgery. In this overview, the status of the autogenous bone is re-evaluated under consideration of current research results, clinical long-term studies, risks and safety of the patient as well as the costs. Due to the further development of modern bone substitute materials, which reveal in parts superior long-term results for special indications, the routine use of autogenous bone has to be critically reviewed.

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700391, In the present study, the interactions between a high bismuth type commercial transparent leadless glaze and a biscuit fired bone china body during glost firing at different temperatures were investigated using SEM. The formation of several phases with different morphological and chemical characteristics was clearly demonstrated. It was found that the interface characteristics were similar to those previously observed at an ABS type commercial transparent leadless glaze-bone china interfaces., Turkish Ceram Soc, European Ceram Soc

Statement of the Problem: The use of autologous tissue-engineered bone would eliminate the problem of donor site morbidity. Successful tissue engineered bone grafts will be dependent on the fabrication of accurate three-dimensional scaffolds. Recently, three-dimensional printing technology (3DPT) developed at the Massachusetts Institute of Technology has allowed the fabrication of geometry-controlled scaffolds. The purpose of this study is to evaluate cell penetration and bone formation on such a 3DPT scaffold. Materials and Methods: Beta-tricalcium phosphate (beta-TCP) scaffolds (Experimental Scaffolds) were made in as a 3D block measuring 20 20 7 mm in size. These scaffolds were fabricated using a TheriForm machine (Series 3200; Therics Inc, Princeton, NJ) and had both large (2 mm in diameter) and small pores (400 microns in diameter). Control scaffolds were made manually using poly-DL-lactic-co-glycolic acid (PLGA). PLGA foam squares cut into chips measuring 7 7 2 mm each. The PLGA chips were placed in a 20 20 7 mm mold and placed in an oven for 8 hours at 65° centigrade. The heat caused the PLGA to melt at the surface, binding the individual foam chip squares together, forming a single, three-dimensional polymer scaffold with an interconnected pore structure (“fused interconnected scaffold”). Porcine mesenchymal stem cells (pMSCs) were isolated from minipig (age 6 months; n 3) iliac crest marrow. The pMSCs were suspended in medium containing osteogenic supplements (OS: 100 nM dexamethasone, 50 g/mL ascorbic acid, and 10 mM -glycerophosphate) and then diluted to 30 106 cells per 35 mL OS medium. The cell suspension was seeded onto PLGA solid and fused interconnected scaffolds. The seeded scaffolds were placed in a rotational oxygenpermeable bioreactor system (ROBS) and incubated for 2, 4, and 6 weeks. Method of Data Analysis: After incubation, scaffolds were examined histologically to assess cell penetration and bone formation. The number of cells in the center of the scaffold was counted in 3 areas and averaged (n 3) using image analysis software (NIH Image 1.62 graphics program; NIH, Bethesda, MD). Bone formation depth was assessed in 3 areas of the scaffold cultured for 6 weeks and averaged (n 3) (Meta Morph version 6.6v4, Universal Imaging Corporation, Downingtown, PA). Results: At 2, 4, and 6 weeks, beta-TCP scaffold exhibited cell penetration of 21, 16.7, 19.6 cells/1.4 mm2 as compared to the fused interconnected scaffold (116.9, 74.3, and 60.4 cells/1.4 mm2). However, beta-TCP scaffolds exhibited comparable bone formation (0.48 mm) to the fused interconnected scaffold (0.42 mm). Conclusion: Beta-TCP scaffold showed less cell penetration but comparable bone formation as compared to the fused interconnected scaffolds in this in vitro model.

Physical, chemical, biological and implant tests on calcium phosphate prepared by the mechanochemical method with wet milling were performed to determine their applicability for periodontal therapy. 1. Materials synthesized by the new method had a stoichiometric ratio of Ca/P = 1.50 and a density of 3.70 g/cm3 and coincided with the standard pattern of beta-TCP (ASTM Card) very well. 2. The surface structure of dense type sintered at 1,100 degrees C showed fewer fine pores than the dense type sintered at 1,050 degrees C. The surface structure of the porous type sintered at 1,050 degrees C showed finer pores, except for a continuous large pore than the porous type sintered at 1,000 degrees C. 3. Specific conductivity tests should higher solubilities of the porous type than of the dense type in pure water, and of materials sintered at low temperature than at high temperature. 4. Cytotoxicity studies with V-79 cells showed no significant differences from the controls, and other biological tests revealed no abnormalities. 5. At three and six weeks after implantation in muscles, all of beta-TCP was enclosed with collagen fiber. The porous type of beta-TCP was almost completely fused to cranical bone in rabbits three weeks after implantation. The dense type of beta-TCP was completely fused to cranical bone six weeks after implantation. From these results, it can be concluded that beta-TCP prepared by the new method is of high purity and biocompatibility. Consequently beta-TCP is expected to be effective in clinical use.

Tricalcium phosphate (TCP) is a biocompatible ceramic bone graft substitute manufactured by DePuy. Since April 1984, over 80 cases have been entered into an FDA-approved clinical study, in which tricalcium phosphate was used as a bone graft material for fractures, nonunions, miscellaneous bone defects, and tumors. This report details early results of its use in 20 benign bone tumors treated at the University Hospital of Arkansas and the J.L. McClellan Memorial Veterans Hospital, Little Rock, Arkansas. The TCP used was a porous granular (18 patients) or block (two patients) polycrystalline ceramic formed by sintering beta TCP at 2000°C. The particle size varies from 0.4 to 2 mm and has a porosity of 250–400 μm.