OBJECTIVETo explore the method to repair bone defect with bone-morphogenetic-protein loaded hydroxyapatite/collagen-poly(L-lactic acid) composite.

METHODS18 adult beagle dogs were randomly divided into 3 groups. In Group A, bone-morphogenetic-protein (BMP) loaded hydroxyapatite/collagen-poly(L-lactic acid) (HAC-PLA) scaffold was implanted in a 2 cm diaphyseal defect in the radius. In Group B, unloaded pure HAC-PLA scaffold was implanted in the defects. No material was implanted in Group C (control group). The dogs were sacrificed 6 months postoperatively. Features of biocompatibility, biodegradability and osteoinduction were evaluated with histological, radiological examinations and bone mineral density (BMD) measurements.

RESULTSIn Group A, the radius defect healed after the treatment with BMP loaded HAC-PLA. BMD at the site of the defect was higher than that of the contralateral radius. Fibrous union developed in the animals of the control group.

CONCLUSIONSBMP not only promotes osteogenesis but also accelerates degradation of the biomaterials. Optimized design parameters of a three-dimensional porous biomaterial would give full scope to the role of BMP as an osteoinductive growth factor.

Animals ; Biocompatible Materials ; therapeutic use ; Bone Morphogenetic Proteins ; therapeutic use ; Bone Substitutes ; therapeutic use ; Collagen ; therapeutic use ; Dogs ; Durapatite ; therapeutic use ; Lactic Acid ; therapeutic use ; Microscopy, Electron, Scanning ; Osseointegration ; Osteogenesis ; Radiography ; Radius ; diagnostic imaging ; pathology ; Wound Healing ; physiology

BACKGROUNDSystemic administration of bisphosphonates has shown promising results in the treatment of osteonecrosis of the femoral head (ONFH). However, few studies have evaluated the efficacy of local zoledronate (ZOL) administration in the treatment of ONFH. The purpose of this study was to investigate whether local administration of bisphosphonate-soaked hydroxyapatite (HA) could improve bone healing in an experimental rabbit model of ONFH.

METHODSThis experimental study was conducted between October 2014 and June 2015. Forty-five rabbits underwent simulated ONFH surgery. Immediately following surgery, they were divided into three groups: model (untreated, n = 15), HA (treated with HA alone, n = 15), and HA + ZOL (treated with HA soaked in a low-dose ZOL solution, n = 15). Histological, immunohistochemical, and quantitative analyses were performed to evaluate bone formation and resorption 2, 4, and 8 weeks after surgery.

RESULTSGross bone matrix and hematopoietic tissue formation were observed in the HA + ZOL group 4 weeks after surgery. The immunohistochemical staining intensities for 5-bromodeoxyuridine, runt-related transcription factor 2, osteocalcin, osteopontin, and osteoprotegerin were significantly higher in the HA + ZOL group than that in the model (P < 0.001, P< 0.001, P< 0.001, P< 0.001, and P = 0.018, respectively) and HA groups (P = 0.003, P = 0.049, P< 0.001, P = 0.020, and P = 0.019, respectively), whereas receptor activator of the nuclear factor-κB ligand staining intensity was significantly lower in the HA + ZOL group than that in the model and HA groups (P = 0.029 and P = 0.015, respectively) 4 weeks after surgery. No significant differences in bone formation or bone resorption marker expression were found between the three groups 2 or 8 weeks after surgery (P > 0.05).

CONCLUSIONSLocal administration of HA soaked in a low-dose ZOL solution increased new bone formation while inhibiting bone resorption in an animal model of ONFH, which might provide new evidence for joint-preserving surgery in the treatment of ONFH.

Animals ; Diphosphonates ; administration & dosage ; therapeutic use ; Durapatite ; administration & dosage ; therapeutic use ; Female ; Femur Head Necrosis ; drug therapy ; metabolism ; Imidazoles ; administration & dosage ; therapeutic use ; Immunohistochemistry ; Male

OBJECTIVETo investigate the treatment effect of mandibular osteoradionecrosis (ORN) by autologous bone marrow mesenchymal stem cells (BMMSC) in miniature pigs.

METHODSSix miniature pigs with mandibular ORN (25 Gy) were used. BMMSC were separated and cultured in vitro and then implanted on to the premolded hydroxyapatite-tricalcium phosphate (HA-TCP). The BMMSC-HA-TCP complexes were implanted into the defective area of mandibular ORN in 4 animals. Implantation of only HA-TCP in 2 animals served as control. Gross observation, spiral CT, coronary CT and histopathologic examination were carried out.

RESULTSFistula disappeared in animals with BMMSC-HA-TCP complexes 3 months after implantation, while fistula was found in controls. Spiral CT analysis showed that cortical bone repair were found 4 months after BMMSC-HA-TCP complexes implantation, while bone damage (cortical and cancellous bone fracture) increased in controls. Histopathologic examination revealed that 4 months later after BMMSC-HA-TCP complexes implantation, new bone formation and bone cells could be observed, but there was a large number of fibrous tissue and no new bone in controls.

CONCLUSIONSTransplantation of autologous BMMSC with HA-TCP may have therapeutic effect in the treatment of mandibular ORN.

Animals ; Bone Marrow Cells ; Calcium Phosphates ; therapeutic use ; Durapatite ; therapeutic use ; Mandibular Diseases ; therapy ; Mesenchymal Stem Cell Transplantation ; Osteoradionecrosis ; therapy ; Swine ; Swine, Miniature ; Transplantation, Autologous

The present study was undertaken to evaluate porous hydroxyapatite (HAp), the powder of which was prepared by a novel aqueous solution combustion technique, as a bone substitute in healing bone defects in vivo, as assessed by radiologic and histopathologic methods, oxytetracycline labeling, and angiogenic features in Bengal goat. Bone defects were created in the diaphysis of the radius and either not filled (group I) or filled with a HAp strut (group II). The radiologic study in group II showed the presence of unabsorbed implants which acted as a scaffold for new bone growth across the defect, and the quality of healing of the bone defect was almost indistinguishable from the control group, in which the defect was more or less similar, although the newly formed bony tissue was more organized when HAp was used. Histologic methods showed complete normal ossification with development of Haversian canals and well-defined osteoblasts at the periphery in group II, whereas the control group had moderate fibro-collagenization and an adequate amount of marrow material, fat cells, and blood vessels. An oxytetracycline labeling study showed moderate activity of new bone formation with crossing-over of new bone trabeculae along with the presence of resorption cavities in group II, whereas in the control group, the process of new bone formation was active from both ends and the defect site appeared as a homogenous non-fluoroscent area. Angiograms of the animals in the control group showed uniform angiogenesis in the defect site with establishment of trans-transplant angiogenesis, whereas in group II there was complete trans-transplant shunting of blood vessel communication. Porous HAp ceramic prepared by an aqueous combustion technique promoted bone formation over the defect, confirming their biologic osteoconductive property.
Angiography/veterinary ; Animals ; Collagen/*therapeutic use ; Durapatite/*therapeutic use ; Fractures, Bone/radiography/therapy/*veterinary ; Goat Diseases/*therapy ; Goats ; Osteogenesis/*physiology ; Oxytetracycline

The feasibility of anterior lumbar intervertebral fusion with artificial bone in place of autogenous bone was investigated. Porous hydroxyapatite (HA)/ZrO2 ceramics loading bone morphogenetic protein (BMP) were implanted after removal of lumbar vertebral disc in rabbits. The adjacent intervertebral discs were also removed by the same way and autogenous illic bone was implanted. SEM observation and biomechanical test were carried out. Compound bone had a bit lower osteoinductive activity than autogenous bone by SEM (Osteoinductive activity of artificial bone in 12 weeks was the same as that of autogenous bone in 9 weeks). Biomechanical test revealed that compound bone had lower anti-pull strength than autogenous bone (P < 0.001), but there was no significant difference in anti-pull strength between compound bone at 12th week and autogenous bone at 9th week (P > 0.05). It was concluded that compound bone could be applied for anterior spinal fusion, especially for those patients who can't use autogenous bone.
Biocompatible Materials/therapeutic use ; Bone Morphogenetic Proteins/*therapeutic use ; Calcium Phosphates ; Durapatite ; Hydroxyapatites ; Implants, Experimental ; Intervertebral Disk/surgery ; Lumbar Vertebrae/*surgery ; Spinal Fusion/*methods ; Spinal Injuries/*surgery

OBJECTIVETo decide the safe dissection plane and evaluate the multiple materials used for the fronto-temporal augmentation.

METHODSClinical anatomical observation were made during the fronto-temporal operations. Forty-one patients were treated for the fronto-temporal augmentation with various granular or patched materials in different anatomical plane.

RESULTSFour relatively safe dissection planes were found in the fronto-temporal area: (1) subcutaneous or above superficial temporal fascia, (2) subgalea plane 1.5 cm above the zygomatic arch, (3) between the deep temporal fascia and the temporal muscle, and (4) beneath the temporal periosteum. With the follow-ups from 6 months to 1 year, the appearance after the fronto-temporal augmentation in each patient was satisfactory or improved, except for the fat granule group with partial absorption and the ePTFE or Medpor hypothesis group shown a stepped contouring at the margin in a few patients.

CONCLUSIONFour dissection planes could be shown in the fronto-temporal region for the augmentation plasty with different advantages and disadvantages. The combination could be overcome the disadvantages to improve the results. Fat granule could be the best autograft for frontotemporal augmentation.

Adult ; Biocompatible Materials ; therapeutic use ; Ceramics ; therapeutic use ; Durapatite ; therapeutic use ; Face ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Materials Testing ; Middle Aged ; Reconstructive Surgical Procedures ; methods ; Surgical Flaps ; Temporal Bone ; surgery ; Treatment Outcome

OBJECTIVETo study the reason and the management of the sunken upper eyelid after implanting a hydroxyapatite platform.

METHODSFrom 1998, we developed a method of subperiosteal implantation at the orbital floor to repair the introcession of the upper eyelid after hydroxyapatite platform implantation. 11 cases of the sunken upper eyelid were treated with this method. The implants included Medpor in 2 cases, hydroxyapatite plates in 7 cases and acellular dermal matrix in 2 cases.

RESULTSPostoperatively, all the patients obtained satisfactory results. Follow-up for 1 to 4 years showed no complications of extrusion or infection of the implants. Re-operation was needless in all of them.

CONCLUSIONSubperiosteal implantation to correct the sunken upper eyelid is a safe and effective method.

Adult ; Durapatite ; therapeutic use ; Eyelids ; abnormalities ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Postoperative Care ; Postoperative Complications ; etiology ; surgery ; Prosthesis Implantation ; adverse effects ; methods ; Treatment Outcome

OBJECTIVE: To observe the effect of daily low-intensity pulsed ultrasound (LIPUs) therapy on improving the enchondral bone formation in lumbar fusion in rabbit models, and to explore its possible mechanism. METHODS: Posterolateral noninstrumented bilateral fusions were performed at the L5 approximately L6 levels in 20 New Zealand rabbits. The autograft iliac bone was implanted on the left side, and the hydroxyapatite bioceramic artificial bone on the right. The rabbits were divided into a treatment group and a control group randomly. One week after the surgery, LIUPs was administered for 20 minutes per day for 4 weeks over the fusion site in the treatment group and false treatment was used in the control group. Post-anterior X-ray photographs were taken to determine the conditions of fusion area, and then, rabbits were killed and the fusion tissues were obtained. Chondrocytes were detected by histological and cytological methods. RESULTS: Compared with the control group, the fusion rate of the treatment group was significantly up-regulated (P<0.05). There was plenty bone trabecula in the fusion area in the treatment group, the number of chondrocytes was also higher than that of the control group (P<0.05), and there was no statistical difference in the number of chondrocytes between the iliac and artificial bone tissues after the treatment(P>0.05). CONCLUSION Low-intensity pulsed ultrasound therapy improves the endochondral bone formation in the lumbar spine fusion in rabbit models.
Animals ; Chondrocytes ; cytology ; Durapatite ; therapeutic use ; Female ; Ilium ; transplantation ; Lumbar Vertebrae ; surgery ; Male ; Osteogenesis ; radiation effects ; Rabbits ; Random Allocation ; Spinal Fusion ; methods ; Ultrasonic Therapy ; methods

The feasibility of anterior lumbar intervertebral fusion with artificial bone in place of autogenous bone was investigated. Porous hydroxyapatite (HA)/ZrO2 ceramics loading bone morphogenetic protein (BMP) were implanted after removal of lumbar vertebral disc in rabbits. The adjacent intervertebral discs were also removed by the same way and autogenous illic bone was implanted. SEM observation and biomechanical test were carried out. Compound bone had a bit lower osteoinductive activity than autogenous bone by SEM (Osteoinductive activity of artificial bone in 12 weeks was the same as that of autogenous bone in 9 weeks). Biomechanical test revealed that compound bone had lower anti-pull strength than autogenous bone (P < 0.001), but there was no significant difference in anti-pull strength between compound bone at 12th week and autogenous bone at 9th week (P > 0.05). It was concluded that compound bone could be applied for anterior spinal fusion, especially for those patients who can't use autogenous bone.
Animals ; Biocompatible Materials ; therapeutic use ; Bone Morphogenetic Proteins ; therapeutic use ; Calcium Phosphates ; Durapatite ; Hydroxyapatites ; Implants, Experimental ; Intervertebral Disc ; surgery ; Lumbar Vertebrae ; surgery ; Rabbits ; Spinal Fusion ; methods ; Spinal Injuries ; surgery

OBJECTIVETo study a new implant material (carbonated hydroxyapatite, CHA) united pedicle screw to cure spine fracture.

METHODSThirty-two cases of spine compressed fracture were used with pedicle screw fixator and vertebroplasty. Before operation, patients' vertebral body were compressed (46 + 21)% (20% approximately 70%) on average. In operation, broken vertebral body was reposition through pedicle screw technique, then used self-made syringe to inject CHA into anterior and central column of broken vertebral body through pedicle. And all of patients were not given any bone-graft.

RESULTSIn 6 - 26 months followed-up, no immunologic rejection was found about hydroxyapatite, and no any broken of the screws and shafts was found, no loosing and other complications either. All the patients could move in 3 - 5 days after operation. The height of the broken vertebral body were reduced 97% compared with pre-operation. And CHA in vertebral body was degraded gradually, and at the same time it was replace by new bone in vertebral body. After operation, VAS score was 61 +/- 32, and there was significant difference compared with pre-operation.

CONCLUSIONSThe pedicle screw fixation united vertebroplasty is an efficient way to prevent the failure of the treatment of spine fracture.

Adult ; Bone Screws ; Bone Substitutes ; therapeutic use ; Durapatite ; therapeutic use ; Female ; Follow-Up Studies ; Fracture Fixation, Internal ; instrumentation ; methods ; Fractures, Compression ; surgery ; Humans ; Male ; Middle Aged ; Spinal Fractures ; surgery ; Vertebroplasty ; methods