- Exposure to Secondhand Smoke Impairs Fracture Healing in Rats. [Journal Article]
- COClin Orthop Relat Res 2016 Nov 30
- CONCLUSIONS: Rats exposed to tobacco smoke showed delayed fracture healing and callus that was characterized by decreased maturity, density, and mechanical resistance, which was confirmed by all assessment methods of this study. Such effects were more evident when animals were exposed to tobacco smoke before and after the fracture. Future studies should be done in human passive smokers to confirm or refute our findings on fracture callus formation.The potential hazardous effects of secondhand smoke on fracture healing in rodents should stimulate future clinical studies in human passive smokers.
- Effects of collagen membrane application and cortical bone perforation on de novo bone formation in periosteal distraction: an experimental study in a rabbit calvaria. [Journal Article]
- OSOral Surg Oral Med Oral Pathol Oral Radiol 2016 Sep 28
- CONCLUSIONS: In the present model, cortical bone perforations have more impact on the osteogenic process compared with the application of a collagen membrane.
- Local Application of Lactoferrin Promotes Bone Regeneration In a Rat Critical-Sized Calvarial Defect Model As Demonstrated by Micro-CT And Histological Analysis. [Journal Article]
- JTJ Tissue Eng Regen Med 2016 Nov 15
- Lactoferrin is a multifunctional glycoprotein with therapeutic potential for bone tissue engineering. The aim of this study was to assess the efficacy of local application of lactoferrin on bone rege...
Lactoferrin is a multifunctional glycoprotein with therapeutic potential for bone tissue engineering. The aim of this study was to assess the efficacy of local application of lactoferrin on bone regeneration. Five-millimetre critical-sized defects were created over the right parietal bone in 64 Sprague-Dawley rats. The rats were randomized into four groups: group 1 (n = 20) had empty defects; group 2 (n = 20) had defects grafted with collagen gels (3 mg/mL); group 3 (n = 20) had defects grafted with collagen gels impregnated with bovine lactoferrin (10 µg/gel) and group 4 (n = 4) had sham surgeries (skin and periosteal incisions only). The rats were euthanized at 4 or 12 weeks post-operatively and the calvaria were excised and evaluated with micro-CT (Skyscan 1172) followed by histology. The bone volume fraction (BV/TV) was higher in lactoferrin treated animals at both time points, with groups 1, 2, 3 and 4 measuring 10.5 ± 1.1%, 8.6 ± 1.4%, 16.5 ± 0.6% and 24.27 ± 2.6%, respectively, at 4 weeks (p < 0.05); and 12.2 ± 1.3%, 13.6 ± 1.5%, 21.9 ± 1.2% and 29.3 ± 0.8%, respectively, at 12 weeks (p < 0.05). Histological analysis revealed that the newly formed bone within the calvarial defects of all groups was a mixture of woven and lamellar bone, with more bone in the group treated with lactoferrin at both timepoints. Our study demonstrated that local application of lactoferrin significantly increased bone regeneration in a rat critical-sized calvarial defect model. The profound effect of lactoferrin on bone regeneration has therapeutic potential to improve the poor clinical outcomes associated with bony non-union.
- Remnant Woven Bone and Calcified Cartilage in Mouse Bone: Differences between Ages/Sex and Effects on Bone Strength. [Journal Article]
- PlosPLoS One 2016; 11(11):e0166476
- Mouse models are used frequently to study effects of bone diseases and genetic determinates of bone strength. Murine bones have an intracortical band of woven bone that is not present in human bones....
Mouse models are used frequently to study effects of bone diseases and genetic determinates of bone strength. Murine bones have an intracortical band of woven bone that is not present in human bones. This band is not obvious under brightfield imaging and not typically analyzed. Due to the band's morphology and location it has been theorized to be remnant bone from early in life. Furthermore, lamellar and woven bone are well known to have differing mechanical strengths. The purpose of this study was to determine (i) if the band is from early life and (ii) if the woven bone or calcified cartilage contained within the band affect whole bone strength.
- Effects of Abaloparatide-SC (BA058) on bone histology and histomorphometry: The ACTIVE phase 3 trial. [Journal Article]
- BONEBone 2016 Nov 5
- There are a number of effective treatments for osteoporosis but most are in the antiresorptive class of compounds. Abaloparatide-SC is a new osteoanabolic agent, which increased bone mineral density ...
There are a number of effective treatments for osteoporosis but most are in the antiresorptive class of compounds. Abaloparatide-SC is a new osteoanabolic agent, which increased bone mineral density and lowered the risk of osteoporosis-related fractures in the phase 3 ACTIVE trial. The objective of this report is to describe the effects of abaloparatide-SC 80μg on bone histology and histomorphometry in iliac crest bone biopsies from this trial in which participants were randomized to receive blinded daily subcutaneous injections of placebo or abaloparatide-SC 80μg/d or open-label teriparatide 20μg/d for 18months. Iliac crest bone biopsies were obtained between 12 and 18months. Qualitative histological analysis of biopsies from abaloparatide-SC-treated patients revealed normal bone microarchitecture without evidence of adverse effects on mineralization or on the formation of normal lamellar bone. There were no bone marrow abnormalities, marrow fibrosis nor presence of excess osteoid or woven bone. There were few significant differences among the three treatment groups in a standard panel of static and dynamic histomorphometric indices. The mineral apposition rate was higher in the teriparatide-treated group than in the placebo-treated group. The eroded surface was lower in the abaloparatide-SC-treated group than in the placebo-treated group. Cortical porosity was higher in both the abaloparatide-SC- and the teriparatide-treated groups than in the placebo-treated group. We conclude that histological and histomorphometric analysis of iliac crest bone biopsies from subjects who were treated for up to 18months with abaloparatide-SC showed no evidence of concern for bone safety.
- Increased osteoinductivity and mineralization by minimal concentration of bone morphogenetic protein-2 loaded onto biphasic calcium phosphate in a rabbit sinus. [Journal Article]
- JPJ Periodontal Implant Sci 2016; 46(5):350-359
- CONCLUSIONS: Within the limitations of this study, it can be suggested that a minimal concentration of BMP-2 (0.05 mg/mL) had an osteoinductive effect with accelerated mineralization in a rabbit sinus model using a BCP carrier.
- In vivo erosion of orthopedic screws prepared from nacre (mother of pearl). [Journal Article]
- OTOrthop Traumatol Surg Res 2016; 102(7):913-918
- CONCLUSIONS: Screws prepared from nacre have the advantage of an in vivo resorbability by macrophage-derived cells and an osteoconductive apposition in contact with the material without triggering a local inflammatory reaction.
- Development of an in vivo bone fatigue damage model using axial compression of the rabbit forelimb. [Journal Article]
- JBJ Biomech 2016 Oct 3; 49(14):3564-3569
- Many nontraumatic fractures seen clinically in patients with metabolic bone disorders or on antiresorptive treatment show an increased incidence of microdamage accumulation and impaired intracortical...
Many nontraumatic fractures seen clinically in patients with metabolic bone disorders or on antiresorptive treatment show an increased incidence of microdamage accumulation and impaired intracortical remodeling. However, the lack of basal remodeling and Haversian bone in rodents limits their translatability in studying bone damage repair mechanisms. The work presented here demonstrates the development of the forelimb loading model in rabbits, the smallest mammal with intracortical Haversian remodeling. The forelimbs of post-mortem female New Zealand white rabbits were loaded in axial end compression to determine their basic monotonic and fatigue properties. Following time zero characterization, stress fractures were created in vivo and animals were allowed to recover for a period of two to five weeks. The rabbit forelimb when loaded in axial compression demonstrates a consistent mid-diaphyseal fracture location characterized by a local mixed compression-bending loading environment. Forelimb apparent stiffness, when fatigue loaded, demonstrates a progressive increase until macrocrack formation, at which time apparent stiffness rapidly declines until failure. Stress fractures in the rabbit ulna display robust periosteal expansion and woven bone formation two weeks following fracture. Subsequent healing at five weeks post-fracture is marked by woven bone densification, resorption and intracortical remodeling along the stress fracture line. The rabbit forelimb fatigue model is a promising new platform by which bone׳s response to damage may be studied.
- Clinicopathological Features of a Series of 27 Cases of Post-Denosumab Treated Giant Cell Tumors of Bones: A Single Institutional Experience at a Tertiary Cancer Referral Centre, India. [Journal Article]
- POPathol Oncol Res 2016 Oct 8
- Giant cell tumor of bone (GCTB) is mostly a benign tumor, but associated with recurrences and metastasis. Lately, denosumab is being utilized in the treatment of certain GCTBs. Twenty-seven tumors, a...
Giant cell tumor of bone (GCTB) is mostly a benign tumor, but associated with recurrences and metastasis. Lately, denosumab is being utilized in the treatment of certain GCTBs. Twenty-seven tumors, analyzed in the present study, occurred in 16 males and 11 females (M: F = 1.45:1), in the age-range of 16 to 47 years (mean = 29.5, median = 29). Most tumors were identified in the tibia(6) and femur(6), followed by the humerus(3), radius(3), pelvis(3), fibula(3), sacrum(1), metacarpal(1) and metatarsal(1) bones. There were 18(66.6 %) primary and 9(33.3 %) recurrent tumors. Exact tumor size (19 cases) varied from 3.7 to 15 cm (mean = 7.8, median = 6.4). Eight of the 19 tumors (42.1 %) had size more than or equal to 8 cm. On histopathologic examination of post-denosumab treated specimens, more than half cases (15)(55.5 %) revealed complete absence of osteoclast-like giant cells (OCLGs) and 12 cases revealed residual OCLGCs. In addition, there was replacement by fibro-osseous tissue, including reactive woven bone or osteoid in most cases, followed by variable amount of spindle cells, hyalinisation, fibrosis and chronic inflammatory cells, including lymphocytes, macrophages and plasma cells. Post-treatment follow-up (25 cases, 92.5 %), over 7-27 months duration (median = 18), revealed 20 cases continuously disease-free. Five patients developed recurrences at 9, 12, 13, 14 and 18 months, respectively. Out of these, who underwent repeat surgical intervention, 4 patients are alive with no evidence of disease and a single patient, planned for a second surgery, is alive-with-disease. Denosumab was mostly offered to patients with large sized, borderline salvageable tumors, in order to decrease the morbidity of index surgical procedure, that led to disappearance of OCLGCs in most cases. Post-denosumab treated GCT cases appear as low grade osteosarcomas on histopathologic examination, but lack the clinical behaviour of an osteosarcoma, therefore may be considered as pseudo malignant bony lesions.
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- Comparison of early osseointegration of SLA(®) and SLActive(®) implants in maxillary sinus augmentation: a pilot study. [Journal Article]
- COClin Oral Implants Res 2016 Sep 29
- CONCLUSIONS: Both time and the use of hydrophilic implant surface had a positive impact on %BIC around implants placed into augmented maxillary sinuses. Hydrophilic implant surfaces also had a positive impact on surrounding tissue composition. Larger trials are needed to better assess and detect differences between these two surfaces in augmented maxillary sinuses.