PURPOSETo develop a novel injectable strontium-containing calcium phosphate cement with collagen.

METHODSA novel calcium phosphate bone cement (CPC) was prepared with the addition of strontium element, collagenl, and modified starch; the injectability, solidification time, microstructure, phase composition, compressive strength, anti-collapsibility and histological properties of material were evaluated.

RESULTSThe results showed that the material could be injected with an excellent performance; the modified starch significantly improved the anti-washout property of cement; with the liquid to solid ratio of 0.3, the largest compressive strength of cement was obtained (48.0 MPa ± 2.3 MPa); histological examination of repair tissue showed that the bone was repaired after 16 weeks; the degradation of cement was consistent with the new bone growth.

CONCLUSIONA novel injectable collagen-strontium-containing CPC with excellent compressive strength and suitable setting time was prepared, with addition of modified starch. The CPC showed a good anti-washout property and the degradation time of the cement met with the new bone growing. This material is supposed to be used in orthopedic and maxillofacial surgery for bone defects.

Animals ; Bone Cements ; chemistry ; therapeutic use ; Calcium Phosphates ; chemistry ; Collagen ; chemistry ; Compressive Strength ; Histocompatibility Testing ; Injections ; Rabbits ; Strontium ; chemistry

OBJECTIVE: To evaluate the osteogenetic character and repairing maxillary sinus superior wall fractures capability of calcium phosphate cement (CPC) before and after combined with recombinant human bone morphogenetie protein-7(rhBMP-7). METHOD: A 10 mmX5 mm bone defect in the maxillary sinus superior wall was induced by surgery in all 24 New Zealand white rabbits. These 24 rabbits were randomly divided into two groups. The defects were repaired with CPC group (n = 12) and CPC/rhBMP-7 group (n = 12). The osteogenesis of bone defect was monitored by gro'ss observation, histological examination, observation under scanning electron microscope and measurement of ALP activity at 6 and 12 weeks after the implantation. RESULT: In group CPC,new bone was found to form slowly and little by little. In group CPC/rhBMP-7, however, new bone was observed to form early and massively. The ALP activity in group CPC showed significant statistical difference with that of group CPC/rhBMP-7 (P < 0.05). CONCLUSION The CPC/rhBMP-7 composite has osteoconductibility and osteoinductibility, comparing the use of CPC/rhBMP-7 with CPC for the repair of orbital fracture, the former show obvious advantage repairing ability in maxillary sinus superior wall defect.
Animals ; Bone Cements ; chemistry ; therapeutic use ; Bone Morphogenetic Protein 7 ; therapeutic use ; Calcium Phosphates ; chemistry ; Disease Models, Animal ; Fractures, Bone ; pathology ; surgery ; Humans ; Maxillary Sinus ; pathology ; Osteogenesis ; Rabbits ; Random Allocation ; Recombinant Proteins ; therapeutic use

OBJECTIVETo assess the clinical outcomes of balloon kyphoplasty assisted with calcium phosphate cement (CPC) in treating osteoporotic vertebral fractures (OVF).

METHODSFrom January 2009 to January 2011, 26 patients with osteoporotic vertebral fractures were treated with balloon kyphoplasty assisted with CPC, including 31 vertebrae. There were 15 males and 11 females with an average age of (71.67 +/- 4.36) years old (ranged from 60 to 89 years). Course of disease was from 0.5 to 7 days with an average of 3.2 days. Clinical outcomes were assessed by the visual analogue scale (VAS) and the oswestry disability index (ODI). Vertebral height loss and kyphotic angle were measured by X-rays.

RESULTSAll patients were followed up for 10 to 24 months with an average of 18 months. Before operation, 24 hours after operation and at final follow-up, VAS scores were 7.91 +/- 1.20, 3.22 +/- 1.12, 1.92 +/- 0.83, respectively; ODI scores were 40.00 +/- 1.15, 17.00 +/- 2.12, 13.00 +/- 1.42, respectivesly; vertebral heights were (18.21 +/- 3.21), (23.82 +/- 3.10), (21.85 +/- 3.24) mm, respectivesly; vertebral kyphosis angles were (18.21 +/- 3.21) degrees, (7.42 +/- 3.13) degrees, (10.01 +/- 3.11) degrees, respectivesly. There was significant difference between preoperation and 24 hours after operation, and between final follow-up and preoperation (P < 0.05). There was no significant difference between final follow-up and 24 hours after operation (P > 0.05).

CONCLUSIONBalloon kyphoplasty assisted with calcium phosphate cement (CPC) is effective for the treatment of osteoporotic vertebral fractures (OVF), which can expeditiously relieve pain and effectively rebuild height of vertebral body and kyphotic angle, and also has advantages of minimal trauma and good security.

Aged ; Aged, 80 and over ; Bone Cements ; Calcium Phosphates ; therapeutic use ; Female ; Humans ; Kyphoplasty ; methods ; Male ; Middle Aged ; Osteoporotic Fractures ; surgery ; Spinal Fractures ; surgery ; Visual Analog Scale

BACKGROUNDA new treatment strategy is to target specific areas of the skeletal system that are prone to clinically significant osteoporotic fractures. We term this strategy as the "local treatment of osteoporosis". The study was performed to investigate the effect of alendronate-loaded calcium phosphate cement (CPC) as a novel drug delivery system for local treatment of osteoorosis.

METHODSAn in vitro study was performed using CPC fabricated with different concentrations of alendronate (ALE, 0, 2, 5, 10 weight percent (wt%)). The microstructure, setting time, infrared spectrum, biomechanics, drug release, and biocompatibility of the composite were measured in order to detect changes when mixing CPC with ALE. An in vivo study was also performed using 30 Sprague-Dawley rats randomly divided into six groups: normal, Sham (ovariectomized (OVX) + Sham), CPC with 2% ALE, 5%ALE, and 10% ALE groups. At 4 months after the implantation of the composite, animals were sacrificed and the caudal vertebrae (levels 4-7) were harvested for micro-CT examination and biomechanical testing.

RESULTSThe setting time and strength of CPC was significantly faster and greater than the other groups. The ALE release was sustained over 21 days, and the composite showed good biocompatibility. In micro-CT analysis, compared with the Sham group, there was a significant increase with regard to volumetric bone mineral density (BMD) and trabecular number (Tb.N) in the treated groups (P < 0.05). Trabecular spacing (Tb.Sp) showed a significant increase in the Sham group compared to other groups (P < 0.01). However, trabecular thickness (Tb.Th) showed no significant difference among the groups. In biomechanical testing, the maximum compression strength and stiffness of trabecular bone in the Sham group were lower than those in the experimental groups.

CONCLUSIONSThe ALE-loaded CPC displayed satisfactory properties in vitro, which can reverse the OVX rat vertebral trabecular bone microarchitecture and biomechanical properties in vivo.

Alendronate ; therapeutic use ; Animals ; Bone Cements ; chemistry ; therapeutic use ; Bone Density ; drug effects ; Calcium Phosphates ; chemistry ; Female ; Osteoporosis ; drug therapy ; Rats ; Rats, Sprague-Dawley

To test the efficacy of two calcium phosphate pastes compared to that of fluoride toothpaste on remineralizing artificial caries in situ, this study had a double-blind crossover in situ design, involving three experimental phases of 14 days each, with an 8-day washout period between phases. Nine healthy subjects participated in the study. The subjects wore removable palatal appliances mounted with six human enamel slabs with artificial caries lesions, and in each of the experimental phases, used one of the following methods two times/day: group A, brushing with 1.0 g of Colgate Regular Flavor, followed by applying 0.25 g of Tooth Mousse Plus; group B, brushing with 0.25 g of Clinpro Tooth Crème; and group C, brushing with 1.0 g of Colgate Regular Flavor. After 14 days, the enamel slabs (54 slabs/group) were embedded in resin, sectioned and examined with a polarized-light microscope, and the lesion areas were quantified using Image-Pro Plus. All experimental groups showed a significant reduction in lesion area compared to the initial lesion area (paired t-test, P<0.001). The mean reduction in lesion area of Groups A, B and C were (0.029±0.010), (0.030±0.009) and (0.027±0.009) mm(2), respectively. There were no statistical differences between groups (Kruskal-Wallis test, P>0.05). All three groups remineralized the enamel slab lesions, indicating model sensitivity to fluoride. Given the differences in usage amounts and treated regimens, Clinpro Tooth Crème provided similar benefits to the fluoride toothpaste; however, no additional benefit of Tooth Mousse Plus was observed when used in conjunction with the fluoride toothpaste.
Calcium Phosphates ; therapeutic use ; Cariostatic Agents ; therapeutic use ; Caseins ; therapeutic use ; Cross-Over Studies ; Dental Caries ; prevention & control ; Dental Enamel ; drug effects ; Dentifrices ; therapeutic use ; Double-Blind Method ; Female ; Fluorides ; therapeutic use ; Humans ; Image Processing, Computer-Assisted ; methods ; Male ; Microscopy, Polarization ; Tooth Remineralization ; methods ; Toothbrushing ; methods ; Toothpastes ; therapeutic use ; Treatment Outcome ; Young Adult

Although renal calcium crystal deposits (nephrocalcinosis) may occur in acute phosphate poisoning as well as type 1 renal tubular acidosis (RTA), hyperphosphatemic hypocalcemia is common in the former while normocalcemic hypokalemia is typical in the latter. Here, as a unique coexistence of these two seperated clinical entities, we report a 30-yr-old woman presenting with carpal spasm related to hypocalcemia (ionized calcium of 1.90 mM/L) due to acute phosphate poisoning after oral sodium phosphate bowel preparation, which resolved rapidly after calcium gluconate intravenously. Subsequently, type 1 RTA due to Sjogren's syndrome was unveiled by sustained hypokalemia (3.3 to 3.4 mEq/L), persistent alkaline urine pH (> 6.0) despite metabolic acidosis, and medullary nephrocalcinosis. Through this case report, the differential points of nephrocalcinosis and electrolyte imbalances between them are discussed, and focused more on diagnostic tests and managements of type 1 RTA.
Acidosis, Renal Tubular/*diagnosis/etiology ; Acute Disease ; Adult ; Antibodies, Antinuclear/blood ; Calcium Gluconate/therapeutic use ; Chronic Disease ; Female ; Humans ; Hydrogen-Ion Concentration ; Hypocalcemia/*chemically induced/complications/drug therapy ; Nephrocalcinosis/complications/*diagnosis/ultrasonography ; Parotid Gland/ultrasonography ; Phosphates/*adverse effects ; Salivary Glands/radionuclide imaging ; Sjogren's Syndrome/complications/*diagnosis/metabolism ; Submandibular Gland/ultrasonography

OBJECTIVETo study the effects of administration or local application of epimedium on the fracture healing in osteoporosis rats.

METHODSEighty-two 4-month old clean female rats, 210-250 g, were randomly divided into the experimental group (n = 75) and the control group (n = 7). The bilateral ovaries were resected in the experimental group, while only little fat tissue around the ovary was resected in the control group. Ten weeks after operation the osteoporosis model was successfully established verified by bone densitometry and scanning electron microscopy (SEM). The femur fracture models were established in the rest 72 rats of the experimental group. They were randomly divided into 3 groups, 24 in each group, i.e., the calcium phosphate cement (CPC) group (Group A), the CPC-epimedium group (Group B), and the epimedium administration group (Group C). The serum alkaline phosphatase (ALP) levels of the 3 groups were determined 2, 4, 8, and 12 weeks after surgery. The vitodynamical test and observation of the histological section were performed.

RESULTSThe serum ALP levels increased to some extent in the 3 groups 2, 4, and 8 weeks after bone fracture surgery. But the increase was more obvious in Group B with statistical difference shown when compared with Group A and C (P < 0.05). The ALP level in Group B decreased to the normal range till the 12th week. The bone fracture had not completely healed in Group C and A. Their ALP levels decreased to some extent, but were still maintained to a comparatively higher level, showing statistical difference when compared with that of Group B (P < 0.05). These results were agreeable with the results of the histological observation. Better bone activity promoting results were shown in Group B. The vitodynamical test results of the femur of Group B were all higher than those of Group A and C at each time point (P < 0.05).

CONCLUSIONSLocal application of epimedium could accelerate the fracture healing in osteoporosis rats. It showed better effects when compared with oral administration at the same dose.

Alkaline Phosphatase ; blood ; Animals ; Bone Cements ; therapeutic use ; Calcium Phosphates ; therapeutic use ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; therapeutic use ; Epimedium ; Female ; Fracture Healing ; drug effects ; Fractures, Bone ; drug therapy ; etiology ; Osteoporosis ; complications ; drug therapy ; Ovariectomy ; Rats

This paper is aimed to assess the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) and bone marrow stromal cell (BMSCs) composited tricalcium phosphate (TCP) in a rat model of posterolateral lumbar intertransverse process fusion. Rat BMSCs were cultured in vitro. Twenty SD rats underwent single-level bilateral intertransverse process spine arthrodesis at L4 and L5. These rats were assigned to two groups according to the graft materials. They received: 10 of the total were treated with the BMSCs with rhBMP-2 and tricalcium phosphate (TCP) as the experimental group, and the other 10 with TCP treatment alone as the control group. All the animals were killed at 4 weeks after surgery and the spine fusion results were assessed by gross inspection, manual palpation, radiography and histology. The fusion rate, the tensile strength and stiffness of the solidly fused levels in the experimental group were statistically higher than that of the controlled group (P < 0.05). These results showed that the spinal fusion could be improved mechanically when rhBMP-2 and BMSCs were added into the TCP.
Animals ; Bone Morphogenetic Protein 2 ; therapeutic use ; Calcium Phosphates ; therapeutic use ; Cells, Cultured ; Combined Modality Therapy ; Female ; Lumbar Vertebrae ; surgery ; Male ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Osseointegration ; physiology ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; therapeutic use ; Spinal Fusion ; methods ; Transforming Growth Factor beta ; therapeutic use

OBJECTIVETo investigate the clinical outcome and fusion rate in patients with idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement.

METHODSFrom October 2006 to March 2008, 24 cases undergoing anterior correction and interbody fusion with calcium phosphate cement were enrolled. All of them were female, with an age ranged from 12 to 25 years. The mean Cobb angle of main curve was 46° ± 5° (range, 40° - 56°) before surgery. During operation, the most proximal and distal disc spaces were filled with rib autograft, while the remaining levels were filled with calcium phosphate cement. The interbody fusion rate, coronal correction and sagittal profile reconstruction were evaluated respectively by using χ² test and t test.

RESULTSInterbody fusion was performed in 103 levels, including 48 levels with rib autograft and 55 levels with calcium phosphate cement. The mean follow-up period was 23.8 months (range, 12 - 33 months) in this series. At the follow-up of 6 months, fusion rate was found as 54.2% in the levels filled with rib autograft, while 50.9% in those filled with calcium phosphate cement. Solid fusion of the whole instrumented area was achieved in all cases with a minimum one-year follow-up. No instrumentation-related complications occurred. The correction rate of main curve was on an average of 76% ± 11% after surgery. A significant difference was found between preoperative and immediate postoperative value in terms of the main curve magnitude (46° ± 5° vs. 14° ± 5°, t = -26.95, P < 0.05). The correction loss of the main curve was -5.1° - 10.4° at the final follow-up. The coronal balance and lower instrumented vertebra tilting were significantly improved after operation. The thoracolumbar kyphosis was significantly reduced postoperatively (t = 3.11, P < 0.05).

CONCLUSIONSatisfactory bone fusion and correction maintenance can be achieved in idiopathic thoracolumbar/lumbar scoliosis treated by anterior instrumentation combined with interbody fusion using calcium phosphate cement.

Adolescent ; Adult ; Bone Cements ; therapeutic use ; Calcium Phosphates ; therapeutic use ; Child ; Female ; Follow-Up Studies ; Humans ; Lumbar Vertebrae ; surgery ; Scoliosis ; surgery ; Spinal Fusion ; methods ; Thoracic Vertebrae ; surgery ; Treatment Outcome ; Young Adult

Alternative sources of mesenchymal stem cells (MSCs) for replacing bone marrow (BM) have been extensively investigated in the field of bone tissue engineering. The purpose of this study was to compare the osteogenic potential of canine MSCs derived from adipose tissue (AT), BM, umbilical cord blood (UCB), and Wharton's jelly (WJ) using in vitro culture techniques and in vivo orthotopic implantation assays. After canine MSCs were isolated from various tissues, the proliferation and osteogenic potential along with vascular endothelial growth factor (VEGF) production were measured and compared in vitro. For the in vivo assay, MSCs derived from each type of tissue were mixed with beta-tricalcium phosphate and implanted into segmental bone defects in dogs. Among the different types of MSCs, AT-MSCs had a higher proliferation potential and BM-MSCs produced the most VEGF. AT-MSCs and UCB-MSCs showed greater in vitro osteogenic potential compared to the other cells. Radiographic and histological analyses showed that all tested MSCs had similar osteogenic capacities, and the level of new bone formation was much higher with implants containing MSCs than cell-free implants. These results indicate that AT-MSCs, UCB-MSCs, and WJ-MSCs can potentially be used in place of BM-MSCs for clinical bone engineering procedures.
Adipocytes, White/cytology/physiology ; Alkaline Phosphatase/metabolism ; Animals ; Biocompatible Materials/metabolism/*therapeutic use ; Bone Diseases/*therapy ; Bone Marrow Cells/cytology/physiology ; Calcification, Physiologic ; Calcium/metabolism ; Calcium Phosphates/metabolism/therapeutic use ; Cell Proliferation ; Dogs ; Female ; Fetal Blood/cytology/physiology ; Flow Cytometry ; Male ; Mesenchymal Stromal Cells/cytology/*metabolism ; *Osteogenesis ; Polyesters/metabolism/therapeutic use ; Tissue Engineering/*methods ; Vascular Endothelial Growth Factor A/metabolism