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Sample records for bone resorption

  1. Understanding coupling between bone resorption and formation

    DEFF Research Database (Denmark)

    Andersen, Thomas Levin; Abdelgawad, Mohamed Essameldim; Kristensen, Helene Bjørg

    2013-01-01

    . Collectively, our observations suggest that arrested reversal cells reflect aborted remodeling cycles that did not progress to the bone formation step. We, therefore, propose that bone loss in postmenopausal osteoporosis does not only result from a failure of the bone formation step, as commonly believed......Bone remodeling requires bone resorption by osteoclasts, bone formation by osteoblasts, and a poorly investigated reversal phase coupling resorption to formation. Likely players of the reversal phase are the cells recruited into the lacunae vacated by the osteoclasts and presumably preparing...... these lacunae for bone formation. These cells, called herein reversal cells, cover >80% of the eroded surfaces, but their nature is not identified, and it is not known whether malfunction of these cells may contribute to bone loss in diseases such as postmenopausal osteoporosis. Herein, we combined...

  2. A novel approach to inhibit bone resorption

    DEFF Research Database (Denmark)

    Panwar, Preety; Søe, Kent; Guido, Rafael VC;

    2016-01-01

    -dihydrotanshinone (DHT1), and the active site inhibitor, odanacatib (ODN), on bone resorption and TGF-ß1 degradation. Cell cultures, Western blot, light and scanning electron microscopy as well as energy dispersive X-ray spectroscopy, molecular modelling and enzymatic assays were used to evaluate the inhibitors. KEY...... RESULTS: DHT1 selectively inhibited the collagenase activity of CatK, without affecting the viability of osteoclasts. Both inhibitors abolished the formation of resorption trenches, with DHT1 having a slightly higher IC50 value than ODN. Maximal reductions of other resorption parameters by DHT1 and ODN...

  3. Mechanisms of Bone Resorption in Periodontitis

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    Stefan A. Hienz

    2015-01-01

    Full Text Available Alveolar bone loss is a hallmark of periodontitis progression and its prevention is a key clinical challenge in periodontal disease treatment. Bone destruction is mediated by the host immune and inflammatory response to the microbial challenge. However, the mechanisms by which the local immune response against periodontopathic bacteria disturbs the homeostatic balance of bone formation and resorption in favour of bone loss remain to be established. The osteoclast, the principal bone resorptive cell, differentiates from monocyte/macrophage precursors under the regulation of the critical cytokines macrophage colony-stimulating factor, RANK ligand, and osteoprotegerin. TNF-α, IL-1, and PGE2 also promote osteoclast activity, particularly in states of inflammatory osteolysis such as those found in periodontitis. The pathogenic processes of destructive inflammatory periodontal diseases are instigated by subgingival plaque microflora and factors such as lipopolysaccharides derived from specific pathogens. These are propagated by host inflammatory and immune cell influences, and the activation of T and B cells initiates the adaptive immune response via regulation of the Th1-Th2-Th17 regulatory axis. In summary, Th1-type T lymphocytes, B cell macrophages, and neutrophils promote bone loss through upregulated production of proinflammatory mediators and activation of the RANK-L expression pathways.

  4. The role of synthetic biomaterials in resorptive alveolar bone regeneration

    OpenAIRE

    2007-01-01

    The alveolar bone tissue resorption defect has a significant role in dentistry. Because of the bone tissue deficit developed by alveolar resorption, the use of synthetic material CP/PLGA (calcium-phosphate/polylactide-co-gliycolide) composite was introduced. Investigations were performed on rats with artificially produced resorption of the mandibular bone. The results show that the best effect on alveolar bone were attained by using nano-composite implants. The effect of the nanocomposite was...

  5. Coupling of Bone Resorption and Formation in Real Time

    DEFF Research Database (Denmark)

    Lassen, Nicolai Ernlund; Andersen, Thomas Levin; Pløen, Gro Grunnet;

    2017-01-01

    and osteoclasts alternate, thus revealing the existence of a mixed "reversal-resorption" phase. 3D reconstructions obtained from serial sections indicated that initial resorption is mainly involved in elongating the canal and the additional resorption events in widening it. Canal diameter measurements show...... that the latter contribute the most to overall resorption. Of note, the density of osteoprogenitors continuously grew along the "reversal/resorption" surface, reaching at least 39 cells/mm on initiation of bone formation. This value was independent of the length of the reversal/resorption surface...

  6. Acidification of the osteoclastic resorption compartment provides insight into the coupling of bone formation to bone resorption

    DEFF Research Database (Denmark)

    Karsdal, Morten A; Henriksen, Kim; Sørensen, Mette G;

    2005-01-01

    Patients with defective osteoclastic acidification have increased numbers of osteoclasts, with decreased resorption, but bone formation that remains unchanged. We demonstrate that osteoclast survival is increased when acidification is impaired, and that impairment of acidification results...... in inhibition of bone resorption without inhibition of bone formation. We investigated the role of acidification in human osteoclastic resorption and life span in vitro using inhibitors of chloride channels (NS5818/NS3696), the proton pump (bafilomycin) and cathepsin K. We found that bafilomycin and NS5818 dose...... dependently inhibited acidification of the osteoclastic resorption compartment and bone resorption. Inhibition of bone resorption by inhibition of acidification, but not cathepsin K inhibition, augmented osteoclast survival, which resulted in a 150 to 300% increase in osteoclasts compared to controls. We...

  7. Role of gastrointestinal hormones in postprandial reduction of bone resorption

    DEFF Research Database (Denmark)

    Henriksen, Dennis B; Alexandersen, Peter; Bjarnason, Nina H;

    2003-01-01

    Collagen type I fragments, reflecting bone resorption, and release of gut hormones were investigated after a meal. Investigations led to a dose escalation study with glucagon like peptide-2 (GLP-2) in postmenopausal women. We found a dose-dependent effect of GLP-2 on the reduction of bone...... resorption....

  8. Bone resorption: an actor of dental and periodontal development?

    Science.gov (United States)

    Gama, Andrea; Navet, Benjamin; Vargas, Jorge William; Castaneda, Beatriz; Lézot, Frédéric

    2015-01-01

    Dental and periodontal tissue development is a complex process involving various cell-types. A finely orchestrated network of communications between these cells is implicated. During early development, communications between cells from the oral epithelium and the underlying mesenchyme govern the dental morphogenesis with successive bud, cap and bell stages. Later, interactions between epithelial and mesenchymal cells occur during dental root elongation. Root elongation and tooth eruption require resorption of surrounding alveolar bone to occur. For years, it was postulated that signaling molecules secreted by dental and periodontal cells control bone resorbing osteoclast precursor recruitment and differentiation. Reverse signaling originating from bone cells (osteoclasts and osteoblasts) toward dental cells was not suspected. Dental defects reported in osteopetrosis were associated with mechanical stress secondary to defective bone resorption. In the last decade, consequences of bone resorption over-activation on dental and periodontal tissue formation have been analyzed with transgenic animals (RANK (Tg) and Opg (-∕-) mice). Results suggest the existence of signals originating from osteoclasts toward dental and periodontal cells. Meanwhile, experiments consisting in transitory inhibition of bone resorption during root elongation, achieved with bone resorption inhibitors having different mechanisms of action (bisphosphonates and RANKL blocking antibodies), have evidenced dental and periodontal defects that support the presence of signals originating bone cells toward dental cells. The aim of the present manuscript is to present the data we have collected in the last years that support the hypothesis of a role of bone resorption in dental and periodontal development.

  9. Systemic alendronate prevents resorption of necrotic bone during revascularization. A bone chamber study in rats

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    Aspenberg Per

    2002-08-01

    Full Text Available Abstract Background Avascular necrosis of bone (osteonecrosis can cause structural failure and subsequent deformation, leading to joint dysfunction and pain. Structural failure is the result of resorption of necrotic bone during revascularization, before new bone has formed or consolidated enough for loadbearing. Bone resorption can be reduced by bisphosphonates. If resorption of the necrotic bone could be reduced during the revascularization phase until sufficient new bone has formed, it would appear that structural failure could be avoided. Methods To test whether resorption of necrotic bone can be prevented, structural grafts were subjected to new bone ingrowth during systemic bisphosphonate treatment in a rat model. Results In rats treated with alendronate the necrotic bone was not resorbed, whereas it was almost entirely resorbed in the controls. Conclusion Systemic alendronate treatment prevents resorption of necrotic bone during revascularization. In patients with osteonecrosis, bisphosphonates may therefore prevent collapse of the necrotic bone.

  10. The role of synthetic biomaterials in resorptive alveolar bone regeneration

    Directory of Open Access Journals (Sweden)

    Kaličanin Biljana M.

    2007-01-01

    Full Text Available The alveolar bone tissue resorption defect has a significant role in dentistry. Because of the bone tissue deficit developed by alveolar resorption, the use of synthetic material CP/PLGA (calcium-phosphate/polylactide-co-gliycolide composite was introduced. Investigations were performed on rats with artificially produced resorption of the mandibular bone. The results show that the best effect on alveolar bone were attained by using nano-composite implants. The effect of the nanocomposite was ascertained by determining the calcium and phosphate content, as a basis of the hydroxyapatite structure. The results show that synthetic CP/PLGA nanocomposite alleviate the rehabilitation of weakened alveolar bone. Due to its osteoconductive effect, CP/PLGA can be the material of choice for bone substitution in the future.

  11. Diphyllin, a novel and naturally potent V-ATPase inhibitor, abrogates acidification of the osteoclastic resorption lacunae and bone resorption

    DEFF Research Database (Denmark)

    Sørensen, Mette G; Henriksen, Kim; Neutzsky-Wulff, Anita V;

    2007-01-01

    Dissolution of the inorganic phase of bone by the osteoclasts mediated by V-ATPase and ClC-7 is a prerequisite for bone resorption. Inhibitors of osteoclastic V-ATPase or ClC-7 are novel approaches for inhibition of osteoclastic bone resorption. By testing natural compounds in acidification assay...

  12. Icariin suppresses bone resorption activity of rabbit osteoclasts in vitro

    Institute of Scientific and Technical Information of China (English)

    HUANG Jian; ZHANG JinChao; ZHANG TianLan; WANG Kui

    2007-01-01

    The effect of icariin on the bone resorption activity of rabbit osteoclasts is assessed in vitro. Osteoclasts were isolated from Japanese white rabbits and cultured on plates with a sterilized bone slice in each well. After treatment with icariin at various concentrations, the bone resorption activity of osteoclasts was evaluated by examining pit areas, superoxide anion (O2-) generation, size and number of actin rings and intracellular calcium concentration [Ca2+]i. As revealed by these data, icariin elicited continuous decline of [Ca2+]1, making actin ring constricted and O2- generation decreased. These events resulted in smaller and fewer pits which indicate suppressed bone resorption activity of rabbit osteoclasts by icariin.

  13. Disassociation of bone resorption and formation by GLP-2

    DEFF Research Database (Denmark)

    Henriksen, Dennis B; Alexandersen, Peter; Hartmann, Bolette

    2007-01-01

    of collagen type I (s-CTX and u-CTX) and u-DPD, markers of bone resorption. In contrast, bone formation, as assessed by serum osteocalcin and procollagen type I N-terminal propeptide (PINP), appeared to be unaffected by treatment with exogenous GLP-2. These effects were further investigated in a 14-day study...

  14. Role of gastrointestinal hormones in postprandial reduction of bone resorption

    DEFF Research Database (Denmark)

    Henriksen, Dennis B; Alexandersen, Peter; Bjarnason, Nina H

    2003-01-01

    Collagen type I fragments, reflecting bone resorption, and release of gut hormones were investigated after a meal. Investigations led to a dose escalation study with glucagon like peptide-2 (GLP-2) in postmenopausal women. We found a dose-dependent effect of GLP-2 on the reduction of bone...

  15. Bone resorption and mineral excretion in rats during spaceflight

    Science.gov (United States)

    Cann, C. E.; Adachi, R. R.

    1983-01-01

    Bone resorption was measured directly in flight and synchronous control rats during COSMOS 1129. Continuous tracer administration techniques were used, with replacement of dietary calcium with isotopically enriched Ca-40 and measurement by neutron activation analysis of the Ca-48 released by the skeleton. There is no large change in bone resorption in rats at the end of 20 days of spaceflight as has been found for bone formation. Based on the time course of changes, the measured 20-25 percent decrease in resorption is probably secondary to a decrease in total body calcium turnover. The excretion of sodium, potassium, and zinc all increase during flight, sodium and potassium to a level four to five times control values.

  16. NOD2 Contributes to Porphyromonas gingivalis–induced Bone Resorption

    Science.gov (United States)

    Prates, T.P.; Taira, T.M.; Holanda, M.C.; Bignardi, L.A.; Salvador, S.L.; Zamboni, D.S.; Cunha, F.Q.; Fukada, S.Y.

    2014-01-01

    The NOD-like receptors are cytoplasmic proteins that sense microbial by-products released by invasive bacteria. Although NOD1 and NOD2 are functionally expressed in cells from oral tissues and play a role triggering immune responses, the role of NOD2 receptor in the bone resorption and in the modulation of osteoclastogenesis is still unclear. We show that in an experimental model of periodontitis with Porphyromonas gingivalis W83, NOD2-/- mice showed lower bone resorption when compared to wild type. Quantitative polymerase chain reaction analysis revealed that wild-type infected mice showed an elevated RANKL/OPG ratio when compared to NOD2-/- infected mice. Moreover, the expression of 2 osteoclast activity markers—cathepsin K and matrix metalloproteinase 9—was significantly lower in gingival tissue from NOD2-/- infected mice compared to WT infected ones. The in vitro study reported an increase in the expression of the NOD2 receptor 24 hr after stimulation of hematopoietic bone marrow cells with M-CSF and RANKL. We also evaluated the effect of direct activation of NOD2 receptor on osteoclastogenesis, by the activation of this receptor in preosteoclasts culture, with different concentrations of muramyl dipeptide. The results show no difference in the number of TRAP-positive cells. Although it did not alter the osteoclasts differentiation, the activation of NOD2 receptor led to a significant increase of cathepsin K expression. We confirm that this enzyme was active, since the osteoclasts resorption capacity was enhanced by muramyl dipeptide stimulation, evaluated in osteoassay plate. These results show that the lack of NOD2 receptor impairs the bone resorption, suggesting that NOD2 receptor could contribute to the progression of bone resorption in experimental model of periodontitis. The stimulation of NOD2 by its agonist, muramyl dipeptide, did not affect osteoclastogenesis, but it does favor the bone resorption capacity identified by increased osteoclast

  17. Peculiarities of the bone tissue resorption under microgravity conditions

    Science.gov (United States)

    Rodionova, N.; Oganov, V.; Polkovenko, O.; Nitsevich, T.

    The actual problem - peculiarities of resorptive processes in the spongiose of thingbones - we studied with the use of tranmissive electron microscopy in experiments on rats (American space station SLS-2) and on monkeys Macaca mulatt? (BION-11). Animals were onboard during 2 weeks. There was established, that the resorption happen with osteoclasts participation. They can create groups of cells. In the osteoclasts population we indicated not typical for the control (ground experiment) "giant" cells, which have on ultrathin sections 5-6 nuclei, many lysosomes, well developed "light" zone and "brush-border". The destruction of minera lized matrix in bone lacunas also happens by the way of osteolytic activity of osteocytes. Lysosome ferments of osteocytes are secreted by the eczocytosis. The osteocytic osteolysis, as well as the osteoclastic one can be seen as a physiological, gormon-dependent mechanism of resorption. The presence of a considerable number of neutrophiles, which enter in some zones of resorption is also typical. When these neutrophiles destruct, they release lysosomic ferments that dissolve the bone matrix. In some zones of resorption we noted the presence of the row from collagen fibrils, which loosed crystals , on mineralized matrix borders. The cell detritus is noted in zones of surface dissolving among crystallic conglomerates. It certificates the processes of osteogenic cells destruction that happen here. So, under the microgravity conditions in zones of adaptive remodeling of the spongiose the processes of the bone tissue resorption happen by some ways, namely: by the functional activization of osteoclasts; by the osteocytic osteolysis increasing; as a result of hydrolytic activity of neutrophiles, entering in these zones, and also by the local demineralization and further destruction of bone matrix surface zones.

  18. Glucose-dependent insulinotropic polypeptide inhibits bone resorption in humans

    DEFF Research Database (Denmark)

    Nissen, Anne; Christensen, Mikkel; Knop, Filip K

    2014-01-01

    -minute glucose clamps with co-infusion of GIP (4 pmol/kg/min for 15 min, followed by 2 pmol/kg/min for 45 min) or placebo. The samples were analyzed for concentrations of degradation products of C-terminal telopeptide of type I collagen (CTX), a bone resorption marker. RESULTS regarding effects...

  19. HIV-1 tat and rev upregulates osteoclast bone resorption

    Directory of Open Access Journals (Sweden)

    Nicholas Chew

    2014-11-01

    Full Text Available Introduction: Disruption in bone homeostasis with increased osteoclastic resorption may lead to osteoporosis. HIV tat has been found to increase differentiation of precursor cells into osteoclast (OC (1. Presence of soluble HIV proteins in virally suppressed HIV patients on ART may drive a bone resorption phenotype. We investigated the role of soluble HIV proteins (tat, gp120 Mn and Bal, rev and p55-gag on osteoclastogenesis and OC resorptive capacity. Methods: Mouse monocyte RAW 264.7 cells were cultured in vitro and induced to differentiate into OCs with 50 ng/mL RANKL and 25 ng/mL mCSF. Medium was supplemented with 100 ng/mL of recombinant HIV tat, gp120 (Mn and Bal, rev, nef and p55-gag, respectively, with zolendronate as negative control. Differentiated OCs were stained for TRAP and counted. OC resorption function was examined by culturing differentiated OCs (in the presence of respective HIV proteins on dentin-coated plates and examining the following (i sealing zone formation, (ii volume of resorption pits and (iii area of resorption pits per field using confocal microscopy. Expression of OC specific genes including NFATc1 and cathepsin K was investigated by qPCR. Reactive oxygen species (ROS production is essential in RANKL-induced OC differentiation (2,3; effect of these proteins on ROS production was assessed using the fluorescent H2DCFH-DA. Mean fluorescence intensity was then measured by flow cytometry. TNFα production by OC precursors when incubated with tat and rev was measured by ELISA. Results: Tat and rev treatment was associated with increased OC formation by 70 and 26%, respectively (p<0.01, relative to control, while zolendronate significantly inhibited OC formation by 75%. Gp120 Mn and Bal, nef and p55-gag treatment had no effect on OC differentiation. Interestingly, neither tat nor rev treatment caused significant increases in sealing zone formation but increased dentin resorption pit area by 28 and 19%, respectively, and

  20. Impact of bone graft harvesting techniques on bone formation and graft resorption

    DEFF Research Database (Denmark)

    Saulacic, Nikola; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    formation and graft resorption in vivo. MATERIAL AND METHODS: Four harvesting techniques were used: (i) corticocancellous blocks particulated by a bone mill; (ii) bone scraper; (iii) piezosurgery; and (iv) bone slurry collected from a filter device upon drilling. The grafts were placed into bone defects...

  1. Resorption of labial bone in maxillary anterior implant

    OpenAIRE

    Cho, Young-Bum; Moon, Seung-Jin; Chung, Chae-Heon; Kim, Hee-Jung

    2011-01-01

    PURPOSE The purpose of this study was to evaluate the amount of resorption and thickness of labial bone in anterior maxillary implant using cone beam computed tomography with Hitachi CB Mercuray (Hitachi, Medico, Tokyo, Japan). MATERIALS AND METHODS Twenty-one patients with 26 implants were followed-up and checked with CBCT. 21 OSSEOTITE NT® (3i/implant Innovations, Florida, USA) and 5 OSSEOTITE® implants (3i/implant Innovations, Florida, USA) were placed at anterior region and they were posi...

  2. The Bone Resorption Inhibitors Odanacatib and Alendronate Affect Post-Osteoclastic Events Differently in Ovariectomized Rabbits

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L;

    2014-01-01

    Odanacatib (ODN) is a bone resorption inhibitor which differs from standard antiresorptives by its ability to reduce bone resorption without decreasing bone formation. What is the reason for this difference? In contrast with other antiresorptives, such as alendronate (ALN), ODN targets only...... the very last step of the resorption process. We hypothesize that ODN may therefore modify the remodeling events immediately following osteoclastic resorption. These events belong to the reversal phase and include recruitment of osteoblasts, which is critical for connecting bone resorption to formation. We...... in the interface between osteoclasts and surrounding osteoblast-lineage cells. This increase is expected to favor the osteoclast-osteoblast interactions required for bone formation. Regarding bone resorption itself, we show that ODN, but not ALN, treatment results in shallower resorption lacunae, a geometry...

  3. Detection of root resorption using dentin and bone markers.

    Science.gov (United States)

    George, A; Evans, C A

    2009-08-01

    OBJECTIVES - To test the hypothesis that during root resorption, organic matrix proteins and cytokines from the surrounding bone and dentin are released into the gingival crevice. MATERIAL AND METHODS - Subjects with mild (resorption (>2 mm) were identified. Control group subjects with no loss of root structure or undergoing orthodontic treatment were also identified. Gingival crevicular fluid (GCF) was collected non-invasively from the mesial and distal sides of each of the four upper incisors by using filter paper strips. The eluted GCF was used for analysis using western blot and enzyme-linked immunosorbent assay (ELISA) techniques. Antibodies used were against osteopontin (OPN), (osteoprotegerin) OPG, and receptor activator of nuclear factor kappa B ligand (RANKL). RESULTS - Western blot analysis showed differential expression of OPN, OPG, and RANKL in the control and root resorbed subjects. However, processed forms of these proteins were only observed in the root resorbed subjects. Results from ELISA with OPG antibodies revealed a difference in OPG concentration between the control and root resorption groups. ELISA results with RANKL antibodies did show a statistically significant difference between the control group and the two study groups. The ratio RANKL/OPG was statistically higher in subjects with severe root resorption than in the control subjects. CONCLUSIONS - Preliminary results confirm the presence of matrix proteins and cytokines in the GCF of root resorbed subjects. Further, OPG was locally present in excess amounts over RANKL and an increased RANKL/OPG in the study groups could be correlated with an increased bone resorption activity during orthodontic tooth movement.

  4. Evidence that Resorption of Bone by Rat Peritoneal Macrophages Occurs in an Acidic Environment

    Science.gov (United States)

    Blair, H. C.

    1985-01-01

    Skeletal loss in space, like any form of osteoporosis, reflects a relative imbalance of the activities of cells resorbing (degrading) or forming bone. Consequently, prevention of weightlessness induced bone loss may theoretically be accomplished by (1) stimulating bone formation or (2) inhibiting bone resorption. This approach, however, requires fundamental understanding of the mechanisms by which cells form or degrade bone, information not yet at hand. An issue central to bone resorption is the pH at which resorption takes place. The pH dependent spectral shift of a fluorescent dye (fluorescein isothiocyanate) conjugated to bone matrix was used to determine the pH at the resorptive cell bone matrix interface. Devitalized rat bone was used as the substrate, and rat peritoneal macrophages were used as the bone resorbing cells. The results suggest that bone resorption is the result of generation of an acidic microenvironment at the cell matrix junction.

  5. Sinusoidal electromagnetic fields promote bone formation and inhibit bone resorption in rat femoral tissues in vitro.

    Science.gov (United States)

    Zhou, Jian; Ma, Xiao-Ni; Gao, Yu-Hai; Yan, Juan-Li; Shi, Wen-Gui; Xian, Cory J; Chen, Ke-Ming

    2016-01-01

    Effects of sinusoidal electromagnetic fields (SEMFs) on bone metabolism have not yet been well defined. The present study investigated SEMF effects on bone formation and resorption in rat femur bone tissues in vitro. Cultured femur diaphyseal (cortical bone) and metaphyseal (trabecular bone) tissues were treated with 50 Hz 1.8 mT SEMFs 1.5 h per day for up to 12 days and treatment effects on bone formation and resorption markers and associated gene expression were examined. Treatment with SEMFs caused a significant increase in alkaline phosphatase (ALP) activity and inhibited the tartrate-resistant acid phosphatase (TRACP) activity in the femoral diaphyseal or metaphyseal tissues. SEMFs also significantly increased levels of mRNA expression of osterix (OSX), insulin-like growth factor (IGF-1) and ALP in the bone tissues. SEMF treatment decreased glucose content and increased lactic acid contents in the culture conditioned medium. In addition, treatment with SEMFs decreased mRNA expression levels of bone resorption-related genes TRACP, macrophage colony stimulating factor (M-CSF) and cathepsin K (CTSK) in the cultured bone tissues. In conclusion, the current study demonstrated that treatment with 1.8 mT SEMFs at 1.5 h per day promoted bone formation, increased metabolism and inhibited resorption in both metaphyseal and diaphyseal bone tissues in vitro.

  6. Age-Related Effects of Advanced Glycation End Products (Ages) in Bone Matrix on Osteoclastic Resorption.

    Science.gov (United States)

    Yang, Xiao; Gandhi, Chintan; Rahman, Md Mizanur; Appleford, Mark; Sun, Lian-Wen; Wang, Xiaodu

    2015-12-01

    Advanced glycation end products (AGEs) accumulate in bone extracellular matrix as people age. Previous studies have shown controversial results regarding the role of in situ AGEs accumulation in osteoclastic resorption. To address this issue, this study cultured human osteoclast cells directly on human cadaveric bone slices from different age groups (young and elderly) to warrant its relevance to in vivo conditions. The cell culture was terminated on the 3rd, 7th, and 10th day, respectively, to assess temporal changes in the number of differentiated osteoclasts, the number and size of osteoclastic resorption pits, the amount of bone resorbed, as well as the amount of matrix AGEs released in the medium by resorption. In addition, the in situ concentration of matrix AGEs at each resorption pit was also estimated based on its AGEs autofluorescent intensity. The results indicated that (1) osteoclastic resorption activities were significantly correlated with the donor age, showing larger but shallower resorption pits on the elderly bone substrates than on the younger ones; (2) osteoclast resorption activities were not significantly dependent on the in situ AGEs concentration in bone matrix, and (3) a correlation was observed between osteoclast activities and the concentration of AGEs released by the resorption. These results suggest that osteoclasts tend to migrate away from initial anchoring sites on elderly bone substrate during resorption compared to younger bone substrates. However, such behavior is not directly related to the in situ concentration of AGEs in bone matrix at the resorption sites.

  7. BIOCHEMICAL MARKERS OF BONE RESORPTION AND HORMONAL REGULATION OF BONE METABOLISM FOLLOWING LIVER TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    V. P. Buzulina

    2013-01-01

    Full Text Available Aim. Comparative evaluation of two biochemical markers of bone resorption and hormonal regulation of bone metabolism in liver recipients. Methods and results. Bоne densitometry of L2–L4 and neck of femur, serum level of some hormones (PTH, vitamin D3, estradiol, testosterone regulating osteoclastogenesis as well as com- parative analyses of two bone resorption markers β-crosslaps and tartrate-resistant acid phosphatase type 5b (TRAP-5b were fulfilled in patients after orthotopic liver transplantation (OLT. In 1 month after OLT bone density reduction of L2–L4 and neck of femur; decrease of vitamin D3, estradiol in women, testosterone in men and increase levels of bone resorption markers were observed. In 1 and 2 years after OLT the rise of bone density, increased levels of PTH, estradiol, testosterone and decreased β-crosslaps levels were revealed, while vitamin D3 and TRAP-5b levels remained stable. Conclusion. TRAP-5b was found to be a more speciffic marker of bone resorption, independent from collagen metabolism in liver. Osteoporosis defined in long-term period after OLT was associated with higher TRAP-5b and revialed in women with low estradiol level. 

  8. Morphological characteristics of frontal sinus and nasal bone focusing on bone resorption and apposition in hypophosphatemic rickets

    DEFF Research Database (Denmark)

    Gjørup, H; Kjaer, I; Sonnesen, Liselotte;

    2013-01-01

    To characterize the size and the morphology of the frontal sinus (i.e., structure evolved by bone resorption) and the nasal bone (i.e., structure evolved by bone formation) in adults with hypophosphatemic rickets (HR) compared with controls.......To characterize the size and the morphology of the frontal sinus (i.e., structure evolved by bone resorption) and the nasal bone (i.e., structure evolved by bone formation) in adults with hypophosphatemic rickets (HR) compared with controls....

  9. Bone resorption facilitates osteoblastic bone metastatic colonization by cooperation of insulin-like growth factor and hypoxia.

    Science.gov (United States)

    Kuchimaru, Takahiro; Hoshino, Takuya; Aikawa, Tomoya; Yasuda, Hisataka; Kobayashi, Tatsuya; Kadonosono, Tetsuya; Kizaka-Kondoh, Shinae

    2014-05-01

    Bone metastasis is a multistep process that includes cancer cell dissemination, colonization, and metastatic growth. Furthermore, this process involves complex, reciprocal interactions between cancer cells and the bone microenvironment. Bone resorption is known to be involved in both osteolytic and osteoblastic bone metastasis. However, the precise roles of the bone resorption in the multistep process of osteoblastic bone metastasis remain unidentified. In this study, we show that bone resorption plays important roles in cancer cell colonization during the initial stage of osteoblastic bone metastasis. We applied bioluminescence/X-ray computed tomography multimodal imaging that allows us to spatiotemporally analyze metastasized cancer cells and bone status in osteoblastic bone metastasis models. We found that treatment with receptor activator of factor-κB ligand (RANKL) increased osteoblastic bone metastasis when given at the same time as intracardiac injection of cancer cells, but failed to increase metastasis when given 4 days after cancer cell injection, suggesting that RANKL-induced bone resorption facilitates growth of cancer cells colonized in the bone. We show that insulin-like growth factor-1 released from the bone during bone resorption and hypoxia-inducible factor activity in cancer cells cooperatively promoted survival and proliferation of cancer cells in bone marrow. These results suggest a mechanism that bone resorption and hypoxic stress in the bone microenvironment cooperatively play an important role in establishing osteoblastic metastasis.

  10. Deletion of FGFR3 in Osteoclast Lineage Cells Results in Increased Bone Mass in Mice by Inhibiting Osteoclastic Bone Resorption.

    Science.gov (United States)

    Su, Nan; Li, Xiaogang; Tang, Yubin; Yang, Jing; Wen, Xuan; Guo, Jingyuan; Tang, Junzhou; Du, Xiaolan; Chen, Lin

    2016-09-01

    Fibroblast growth factor receptor 3 (FGFR3) participates in bone remodeling. Both Fgfr3 global knockout and activated mice showed decreased bone mass with increased osteoclast formation or bone resorption activity. To clarify the direct effect of FGFR3 on osteoclasts, we specifically deleted Fgfr3 in osteoclast lineage cells. Adult mice with Fgfr3 deficiency in osteoclast lineage cells (mutant [MUT]) showed increased bone mass. In a drilled-hole defect model, the bone remodeling of the holed area in cortical bone was also impaired with delayed resorption of residual woven bone in MUT mice. In vitro assay demonstrated that there was no significant difference between the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts derived from wild-type and Fgfr3-deficient bone marrow monocytes, suggesting that FGFR3 had no remarkable effect on osteoclast formation. The bone resorption activity of Fgfr3-deficient osteoclasts was markedly decreased accompanying with downregulated expressions of Trap, Ctsk, and Mmp 9. The upregulated activity of osteoclastic bone resorption by FGF2 in vitro was also impaired in Fgfr3-deficient osteoclasts, indicating that FGFR3 may participate in the regulation of bone resorption activity of osteoclasts by FGF2. Reduced adhesion but not migration in osteoclasts with Fgfr3 deficiency may be responsible for the impaired bone resorption activity. Our study for the first time genetically shows the direct positive regulation of FGFR3 on osteoclastic bone resorption. © 2016 American Society for Bone and Mineral Research.

  11. Bone balance within a cortical BMU: local controls of bone resorption and formation.

    Directory of Open Access Journals (Sweden)

    David W Smith

    Full Text Available Maintaining bone volume during bone turnover by a BMU is known as bone balance. Balance is required to maintain structural integrity of the bone and is often dysregulated in disease. Consequently, understanding how a BMU controls bone balance is of considerable interest. This paper develops a methodology for identifying potential balance controls within a single cortical BMU. The theoretical framework developed offers the possibility of a directed search for biological processes compatible with the constraints of balance control. We first derive general control constraint equations and then introduce constitutive equations to identify potential control processes that link key variables that describe the state of the BMU. The paper describes specific local bone volume balance controls that may be associated with bone resorption and bone formation. Because bone resorption and formation both involve averaging over time, short-term fluctuations in the environment are removed, leaving the control systems to manage deviations in longer-term trends back towards their desired values. The length of time for averaging is much greater for bone formation than for bone resorption, which enables more filtering of variability in the bone formation environment. Remarkably, the duration for averaging of bone formation may also grow to control deviations in long-term trends of bone formation. Providing there is sufficient bone formation capacity by osteoblasts, this leads to an extraordinarily robust control mechanism that is independent of either osteoblast number or the cellular osteoid formation rate. A complex picture begins to emerge for the control of bone volume. Different control relationships may achieve the same objective, and the 'integration of information' occurring within a BMU may be interpreted as different sets of BMU control systems coming to the fore as different information is supplied to the BMU, which in turn leads to different observable

  12. Bone balance within a cortical BMU: local controls of bone resorption and formation.

    Science.gov (United States)

    Smith, David W; Gardiner, Bruce S; Dunstan, Colin

    2012-01-01

    Maintaining bone volume during bone turnover by a BMU is known as bone balance. Balance is required to maintain structural integrity of the bone and is often dysregulated in disease. Consequently, understanding how a BMU controls bone balance is of considerable interest. This paper develops a methodology for identifying potential balance controls within a single cortical BMU. The theoretical framework developed offers the possibility of a directed search for biological processes compatible with the constraints of balance control. We first derive general control constraint equations and then introduce constitutive equations to identify potential control processes that link key variables that describe the state of the BMU. The paper describes specific local bone volume balance controls that may be associated with bone resorption and bone formation. Because bone resorption and formation both involve averaging over time, short-term fluctuations in the environment are removed, leaving the control systems to manage deviations in longer-term trends back towards their desired values. The length of time for averaging is much greater for bone formation than for bone resorption, which enables more filtering of variability in the bone formation environment. Remarkably, the duration for averaging of bone formation may also grow to control deviations in long-term trends of bone formation. Providing there is sufficient bone formation capacity by osteoblasts, this leads to an extraordinarily robust control mechanism that is independent of either osteoblast number or the cellular osteoid formation rate. A complex picture begins to emerge for the control of bone volume. Different control relationships may achieve the same objective, and the 'integration of information' occurring within a BMU may be interpreted as different sets of BMU control systems coming to the fore as different information is supplied to the BMU, which in turn leads to different observable BMU behaviors.

  13. Erk1 positively regulates osteoclast differentiation and bone resorptive activity.

    Directory of Open Access Journals (Sweden)

    Yongzheng He

    Full Text Available The extracellular signal-regulated kinases (ERK1 and 2 are widely-expressed and they modulate proliferation, survival, differentiation, and protein synthesis in multiple cell lineages. Altered ERK1/2 signaling is found in several genetic diseases with skeletal phenotypes, including Noonan syndrome, Neurofibromatosis type 1, and Cardio-facio-cutaneous syndrome, suggesting that MEK-ERK signals regulate human skeletal development. Here, we examine the consequence of Erk1 and Erk2 disruption in multiple functions of osteoclasts, specialized macrophage/monocyte lineage-derived cells that resorb bone. We demonstrate that Erk1 positively regulates osteoclast development and bone resorptive activity, as genetic disruption of Erk1 reduced osteoclast progenitor cell numbers, compromised pit formation, and diminished M-CSF-mediated adhesion and migration. Moreover, WT mice reconstituted long-term with Erk1(-/- bone marrow mononuclear cells (BMMNCs demonstrated increased bone mineral density as compared to recipients transplanted with WT and Erk2(-/- BMMNCs, implicating marrow autonomous, Erk1-dependent osteoclast function. These data demonstrate Erk1 plays an important role in osteoclast functions while providing rationale for the development of Erk1-specific inhibitors for experimental investigation and/or therapeutic modulation of aberrant osteoclast function.

  14. The role of probiotic on alveolar bone resorption

    Directory of Open Access Journals (Sweden)

    Desi Sandra Sari

    2011-09-01

    Full Text Available Background: Probiotics are microbes derived from the group of lactic acid bacteria that work to maintain the health of hosts. Probiotics can also be used to improve oral health. Periodontal disease is usually marked with gingival inflammation and alveolar bone resorption. Gram negative anaerobic bacteria that play important role in human periodontal disease are Porphyromonas gingivalis. (P. gingivalis. P. gingivalis is a virulent bacteria in vivo or in vitro, and mostly found in subgingival plaque of periodontitis patients. Purpose: This study is aimed to know the role of probiotics to inhibit the resorption of alveolar bone induced with P. gingivalis. Methods: This study used male wistar rats divided into 4 groups. Group I was control group (without treatment; group II was induced with P. gingivalis ATCC 33277 for 5 days; group III was induced with P. gingivalis ATCC 33277 and also injected with probiotics (Lactobacillus casei ATCC 4224 for 5 days simultaneously; and group IV was induced with P. gingivalis ATCC 33277 for 5 days and also injected by probiotics (Lactobacillus casei ATCC 4224 in the next 5 days. After that, the samples were decapitated, taken their alveolar bone, and then were examined by immunohistochemistry to observe osteoclast activity in alveolar bone resorption by using tartrate-resistant acid phosphatase (TRAP expression. All data were then analyzed statistically. Results: It is known that there were significant differences of TRAP expression among all those treatment groups (p < 0.05. Conclusion: It then can be concluded that probiotics can decrease osteoclast activity in periodontal tissue of wistar rats, so it can inhibit alveolar bone resorption.Latar belakang: Probiotik adalah mikroba dari golongan bakteri asam laktat yang bekerja mempertahankan kesehatan host dan probiotik dapat digunakan untuk meningkatkan kesehatan rongga mulut. Penyakit periodontal ditandai dengan adanya keradangan pada gingiva dan resobsi tulang

  15. Epigallocatechin gallate (EGCG) suppresses lipopolysaccharide-induced inflammatory bone resorption, and protects against alveolar bone loss in mice.

    Science.gov (United States)

    Tominari, Tsukasa; Matsumoto, Chiho; Watanabe, Kenta; Hirata, Michiko; Grundler, Florian M W; Miyaura, Chisato; Inada, Masaki

    2015-01-01

    Epigallocatechin gallate (EGCG), a major polyphenol in green tea, possesses antioxidant properties and regulates various cell functions. Here, we examined the function of EGCG in inflammatory bone resorption. In calvarial organ cultures, lipopolysaccharide (LPS)-induced bone resorption was clearly suppressed by EGCG. In osteoblasts, EGCG suppressed the LPS-induced expression of COX-2 and mPGES-1 mRNAs, as well as prostaglandin E2 production, and also suppressed RANKL expression, which is essential for osteoclast differentiation. LPS-induced bone resorption of mandibular alveolar bones was attenuated by EGCG in vitro, and the loss of mouse alveolar bone mass was inhibited by the catechin in vivo.

  16. Bone resorption in incompletely impacted mandibular third molars and acute pericoronitis

    Directory of Open Access Journals (Sweden)

    Minoru Yamaoka

    2009-04-01

    Full Text Available Minoru Yamaoka, Yusuke Ono, Masahiro Takahashi, Ryosuke Doto, Kouichi Yasuda, Takashi Uematsu, Kiyofumi FurusawaMatsumoto Dental University, School of Dentistry, Shiojiri, Nagano, JapanAbstract: Acute pericoronitis (AP arises frequently in incompletely impacted mandibular third molars, but it remains unknown whether bone resorption in aging is associated with acute inflammation of the third molar. We conducted an experiment to compare the ratio of bone resorption to root length in the distal surface of the second molar (A, the proximal surface (B, and distal surface (C in mesio-angular, incompletely impacted third molars in 27 young and 58 older adults with AP and 77 young and 79 older adults without a history of AP. Bone resorption in A, B, and C in older adults with AP demonstrated a significantly higher ratio when compared to those without AP, whereas there was no difference between those with and without AP in young adults except for B in women. However, there were no differences between bone resorption in B with AP in young and older women, and between bone resorption in C with AP in young and older adults. These indicate that AP and bone resorption are associated with incompletely impacted mandibular third molars in older adults.Keywords: bone resorption, pericoronitis, mandible, acute inflammation, elderly

  17. A physical mechanism for coupling bone resorption and formation in adult human bone

    DEFF Research Database (Denmark)

    Andersen, Thomas Levin; Sondergaard, Teis Esben; Skorzynska, Katarzyna Ewa

    2009-01-01

    During skeletal remodeling, pre-osteoclasts and pre-osteoblasts are targeted to critical sites of the bone to resorb and reconstruct bone matrix, respectively. Coordination of site-specific recruitment of these two cell types is a prerequisite to maintain the specific architecture of each bone...... within strict limits throughout adult life. Here, we determined that the bone marrow microanatomy adjacent to remodeling areas is a central player in this process. By using histomorphometry and multiple immunostainings, we demonstrated in biopsies exhibiting coupled bone resorption and formation...... that osteoclasts and osteoblasts on the bone surface were always covered by a canopy of flat cells expressing osteoblast markers. In contrast, in biopsies in which this canopy was disrupted, bone formation was deficient. Three-dimensional visualizations revealed that this canopy covered the entire remodeling site...

  18. The chloride channel inhibitor NS3736 [corrected] prevents bone resorption in ovariectomized rats without changing bone formation

    DEFF Research Database (Denmark)

    Schaller, Sophie; Henriksen, Kim; Sveigaard, Christina

    2004-01-01

    formation. This study indicates that chloride channel inhibitors are highly promising for treatment of osteoporosis. INTRODUCTION: The chloride channel inhibitor, NS3736, blocked osteoclastic acidification and resorption in vitro with an IC50 value of 30 microM. When tested in the rat ovariectomy model......: In conclusion, we show for the first time that chloride channel inhibitors can be used for prevention of ovariectomy-induced bone loss without impeding bone formation. We speculate that the coupling of bone resorption to bone formation is linked to the acidification of the resorption lacunae, thereby enabling...

  19. The effect of resorption cavities on bone stiffness is site dependent.

    Science.gov (United States)

    Vanderoost, Jef; van Lenthe, G Harry

    2014-01-01

    Resorption cavities formed during the bone remodelling cycle change the structure and thus the mechanical properties of trabecular bone. We tested the hypotheses that bone stiffness loss due to resorption cavities depends on anatomical location, and that for identical eroded bone volumes, cavities would cause more stiffness loss than homogeneous erosion. For this purpose, we used beam-shell finite element models. This new approach was validated against voxel-based FE models. We found an excellent agreement for the elastic stiffness behaviour of individual trabeculae in axial compression (R(2) = 1.00) and in bending (R(2)>0.98), as well as for entire trabecular bone samples to which resorption cavities were digitally added (R(2) = 0.96, RMSE = 5.2%). After validation, this new method was used to model discrete cavities, with dimensions taken from a statistical distribution, on a dataset of 120 trabecular bone samples from three anatomical sites (4th lumbar vertebra, femoral head, iliac crest). Resorption cavities led to significant reductions in bone stiffness. The largest stiffness loss was found for samples from the 4th lumbar vertebra, the lowest for femoral head samples. For all anatomical sites, resorption cavities caused significantly more stiffness loss than homogeneous erosion did. This novel technique can be used further to evaluate the impact of resorption cavities, which are known to change in several metabolic bone diseases and due to treatment, on bone competence.

  20. Impairment of osteoclastic bone resorption in rapidly growing female p47phox knockout mice

    Science.gov (United States)

    Bone formation is dependent on the activity and differentiation of osteoblasts; whereas resorption of preexisting mineralized bone matrix by osteoclasts is necessary not only for bone development but also for regeneration and remodeling. Bone remodeling is a process in which osteoblasts and osteocla...

  1. Longitudinal in vivo imaging of bone formation and resorption using fluorescence molecular tomography.

    Science.gov (United States)

    Lambers, F M; Stuker, F; Weigt, C; Kuhn, G; Koch, K; Schulte, F A; Ripoll, J; Rudin, M; Müller, R

    2013-02-01

    Bone research often focuses on anatomical imaging of the bone microstructure, but in order to gain better understanding in how bone remodeling is modulated through interventions also bone formation and resorption processes should be investigated. With this in mind, the purpose of this study was to establish a longitudinal in vivo imaging approach of bone formation and resorption using fluorescence molecular tomography (FMT). In this study the reproducibility, accuracy and sensitivity of FMT for bone imaging were assessed by performing longitudinal measurements with FMT and comparing it to in vivo micro-computed tomography on a set of control mice, and mice in which load-adaptation was induced in the sixth caudal vertebra. The precision error for FMT measurements, expressed as coefficient of variation, was smaller than 16%, indicating acceptable reproducibility. A correlation was found between bone resorption measured with FMT and bone resorption rate measured with in vivo micro-computed tomography only over the first 14days (R=0.81, pbone formation measured with FMT and bone formation rate measured with in vivo micro-CT. Bone formation measured by FMT was 89-109% greater (pBone resorption was 5-8% lower, but did not reach a significant difference between groups, indicating moderate sensitivity for FMT. In conclusion, in vivo FMT in mouse tail bones is feasible but needs to be optimized for monitoring load adaptation in living mice.

  2. An automatic early stage alveolar-bone-resorption evaluation method on digital dental panoramic radiographs

    Science.gov (United States)

    Zhang, Min; Katsumata, Akitoshi; Muramatsu, Chisako; Hara, Takeshi; Suzuki, Hiroki; Fujita, Hiroshi

    2014-03-01

    Periodontal disease is a kind of typical dental diseases, which affects many adults. The presence of alveolar bone resorption, which can be observed from dental panoramic radiographs, is one of the most important signs of the progression of periodontal disease. Automatically evaluating alveolar-bone resorption is of important clinic meaning in dental radiology. The purpose of this study was to propose a novel system for automated alveolar-bone-resorption evaluation from digital dental panoramic radiographs for the first time. The proposed system enables visualization and quantitative evaluation of alveolar bone resorption degree surrounding the teeth. It has the following procedures: (1) pre-processing for a test image; (2) detection of tooth root apices with Gabor filter and curve fitting for the root apex line; (3) detection of features related with alveolar bone by using image phase congruency map and template matching and curving fitting for the alveolar line; (4) detection of occlusion line with selected Gabor filter; (5) finally, evaluation of the quantitative alveolar-bone-resorption degree in the area surrounding teeth by simply computing the average ratio of the height of the alveolar bone and the height of the teeth. The proposed scheme was applied to 30 patient cases of digital panoramic radiographs, with alveolar bone resorption of different stages. Our initial trial on these test cases indicates that the quantitative evaluation results are correlated with the alveolar-boneresorption degree, although the performance still needs further improvement. Therefore it has potential clinical practicability.

  3. Is there evidence that barrier membranes prevent bone resorption in autologous bone grafts during the healing period? A systematic review

    NARCIS (Netherlands)

    Gielkens, Pepijn F. M.; Bos, Ruud R. M.; Raghoebar, Gerry M.; Stegenga, Boudewijn

    2007-01-01

    Introduction: Autologous bone is considered the "reference standard" for bone-grafting procedures. A barrier membrane covering an autologous bone graft (guided bone regeneration [GBR]) is expected to prevent graft resorption. Good clinical results have been reported for GBR, although potential compl

  4. Prospective study of alveolar bone resorption after radiotherapy and chemotherapy. Etude prospective de la resorption osseuse alveolaire apres radiotherapie et chimiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Libersa, P. (Faculte de Chirurgie Dentaire, 59 - Lille (France)); Prevost, B.; Mirabel, X.; Poissonnier, B.; Demaille, A. (Centre de Lutte Contre le Cancer Oscar-Lambret, 59 - Lille (France)); Laude, M. (Laboratoire de craniologie humaine et comparee, 80 - Amiens (France))

    1993-01-01

    A prospective comparative study of the alveolar bone resorption after teeth extraction was achieved in a series of 79 patients in order to analyze macroscopically the possible consequences of radiotherapy and chemotherapy on the toothless edges. After quarterly coronal and sagittal X-rays for two years, this study enhances quite a similar vertical resorption for the radiation and chemotherapy-treated patients as well as for the witness patients. The alveolar bone resorption progression also appears unaltered by anti cancerous treatments. In both cases, a resorption stabilization can be clearly seen after 6 months according to dental extractions. The vertical alveolar bone resorption is more important in incisor and canin regions. The anti cancerous treatments may not have significant disastrous consequences as fas as available bone amount is concerned, on a post prosthetic restoration.

  5. Response of Bone Resorption Markers to Aristolochia longa Intake by Algerian Breast Cancer Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Bachir Benarba

    2014-01-01

    Full Text Available Aristolochia longa is widely used in traditional medicine in Algeria to treat breast cancer. The aim of the present study was to investigate the response of bone resorption markers to A. longa intake by Algerian breast cancer postmenopausal women. According to the A. longa intake, breast cancer patients were grouped into A. longa group (Al (n=54 and non-A. longa group (non-Al (n=24. 32 women constituted the control group. Bone resorption markers (from urine pyridinoline (PYD and deoxypyridinoline (DPD were determined by HPLC. Serum and urinary creatinine, uric acid, and urea were measured. 1 g of A. longa intake resulted in significant rise of renal serum markers and a pronounced increase of bone resorption markers. The intake of A. longa roots is detrimental for kidney function and resulted in high bone resorption, maybe due to the reduction in renal function caused by the aristolochic acids contained in the roots.

  6. Self-assembling bisphosphonates into nanofibers to enhance their inhibitory capacity on bone resorption

    Science.gov (United States)

    Tang, Anming; Qian, Yu; Liu, Shuang; Wang, Weijuan; Xu, Bing; Qin, An; Liang, Gaolin

    2016-05-01

    Osteoporosis (OP) is an important aging-related disease and the effective prevention/treatment of this disease remains challenging. Considering the acidic microenvironment of bone resorption lacunae, herein, we rationally designed two pamidronate (Pami)-derivative and alendronate (Alen)-derivative hydrogelators Pami-D and Alen-D which self-assemble into nanofibers to form supramolecular hydrogels under acidic conditions. Cell viability assay, osteoclastogenesis, osteoclastic gene expression, and in vitro bone resorption results indicated that both Pami-D and Alen-D have better inhibitory effects on osteoclastic formation and bone resorption than Pami and Alen, respectively. We anticipate that our new drugs Pami-D and Alen-D could ``smartly'' self-assemble and locally concentrate the drugs at bone resorption lacunae in vivo and subsequently prevent/treat osteoporosis more efficiently.Osteoporosis (OP) is an important aging-related disease and the effective prevention/treatment of this disease remains challenging. Considering the acidic microenvironment of bone resorption lacunae, herein, we rationally designed two pamidronate (Pami)-derivative and alendronate (Alen)-derivative hydrogelators Pami-D and Alen-D which self-assemble into nanofibers to form supramolecular hydrogels under acidic conditions. Cell viability assay, osteoclastogenesis, osteoclastic gene expression, and in vitro bone resorption results indicated that both Pami-D and Alen-D have better inhibitory effects on osteoclastic formation and bone resorption than Pami and Alen, respectively. We anticipate that our new drugs Pami-D and Alen-D could ``smartly'' self-assemble and locally concentrate the drugs at bone resorption lacunae in vivo and subsequently prevent/treat osteoporosis more efficiently. Electronic supplementary information (ESI) available: Experiment methods and details; syntheses and characterization of Pami-D and Alen-D; HPLC conditions; Fig. S1-S15, Schemes S1 and S2, Tables S1 and S2

  7. Peptide aldehyde inhibitors of cathepsin K inhibit bone resorption both in vitro and in vivo.

    Science.gov (United States)

    Votta, B J; Levy, M A; Badger, A; Bradbeer, J; Dodds, R A; James, I E; Thompson, S; Bossard, M J; Carr, T; Connor, J R; Tomaszek, T A; Szewczuk, L; Drake, F H; Veber, D F; Gowen, M

    1997-09-01

    We have shown previously that cathepsin K, a recently identified member of the papain superfamily of cysteine proteases, is expressed selectively in osteoclasts and is the predominant cysteine protease in these cells. Based upon its abundant cell type-selective expression, potent endoprotease activity at low pH and cellular localization at the bone interface, cathepsin K has been proposed to play a specialized role in osteoclast-mediated bone resorption. In this study, we evaluated a series of peptide aldehydes and demonstrated that they are potent cathepsin K inhibitors. These compounds inhibited osteoclast-mediated bone resorption in fetal rat long bone (FRLB) organ cultures in vitro in a concentration-dependent manner. Selected compounds were also shown to inhibit bone resorption in a human osteoclast-mediated assay in vitro. Chz-Leu-Leu-Leu-H (in vitro enzyme inhibition Ki,app = 1.4 nM) inhibited parathyroid hormone (PTH)-stimulated resorption in the FRLB assay with an IC-50 of 20 nM and inhibited resorption by isolated human osteoclasts cultured on bovine cortical bone slices with an IC-50 of 100 nM. In the adjuvant-arthritic (AA) rat model, in situ hybridization studies demonstrated high levels of cathepsin K expression in osteoclasts at sites of extensive bone loss in the distal tibia. Cbz-Leu-Leu-Leu-H (30 mg/kg, intraperitoneally) significantly reduced this bone loss, as well as the associated hind paw edema. In the thyroparathyriodectomized rat model, Cbz-Leu-Leu-Leu-H inhibited the increase in blood ionized calcium induced by a 6 h infusion of PTH. These data indicate that inhibitors of cathepsin K are effective at reducing osteoclast-mediated bone resorption and may have therapeutic potential in diseases of excessive bone resorption such as rheumatoid arthritis or osteoporosis.

  8. Inhibitory regulation of osteoclast bone resorption by signal regulatory protein alpha

    NARCIS (Netherlands)

    E.M. van Beek; T.J. de Vries; L. Mulder; T. Schoenmaker; K.A. Hoeben; T. Matozaki; G.E.J. Langenbach; G. Kraal; V. Everts; T.K. van den Berg

    2009-01-01

    Osteoclasts mediate bone resorption, which is critical for bone development, maintenance, and repair. Proper control of osteoclast development and function is important and deregulation of these processes may lead to bone disease, such as osteoporosis. Previous studies have shown that the cytosolic

  9. Bone resorption in incompletely impacted mandibular third molars and acute pericoronitis.

    Science.gov (United States)

    Yamaoka, Minoru; Ono, Yusuke; Takahashi, Masahiro; Doto, Ryosuke; Yasuda, Kouichi; Uematsu, Takashi; Furusawa, Kiyofumi

    2009-01-01

    Acute pericoronitis (AP) arises frequently in incompletely impacted mandibular third molars, but it remains unknown whether bone resorption in aging is associated with acute inflammation of the third molar. We conducted an experiment to compare the ratio of bone resorption to root length in the distal surface of the second molar (A), the proximal surface (B), and distal surface (C) in mesio-angular, incompletely impacted third molars in 27 young and 58 older adults with AP and 77 young and 79 older adults without a history of AP. Bone resorption in A, B, and C in older adults with AP demonstrated a significantly higher ratio when compared to those without AP, whereas there was no difference between those with and without AP in young adults except for B in women. However, there were no differences between bone resorption in B with AP in young and older women, and between bone resorption in C with AP in young and older adults. These indicate that AP and bone resorption are associated with incompletely impacted mandibular third molars in older adults.

  10. Advanced glycation end products biphasically modulate bone resorption in osteoclast-like cells.

    Science.gov (United States)

    Li, Ziqing; Li, Chaohong; Zhou, Yuhuan; Chen, Weishen; Luo, Guotian; Zhang, Ziji; Wang, Haixing; Zhang, Yangchun; Xu, Dongliang; Sheng, Puyi

    2016-03-01

    Advanced glycation end products (AGEs) disturb bone remodeling during aging, and this process is accelerated in diabetes. However, their role in modulation of osteoclast-induced bone resorption is controversial, with some studies indicating that AGEs enhance bone resorption and others showing the opposite effect. We determined whether AGEs present at different stages of osteoclast differentiation affect bone resorption differently. Based on increased levels of tartrate-resistant acid phosphatase (TRAP) and cathepsin K (CTSK), we identified day 4 of induction as the dividing time of cell fusion stage and mature stage in RAW264.7 cell-derived osteoclast-like cells (OCLs). AGE-modified BSA (50-400 μg/ml) or control BSA (100 μg/ml) was then added at the beginning of each stage. Results showed that the presence of AGEs at the cell fusion stage reduced pit numbers, resorption area, and CTSK expression. Moreover, expression of receptor activator of nuclear factor-κB (RANK) as well as the number of TRAP-positive cells, nuclei per OCL, actin rings, and podosomes also decreased. However, the presence of AGEs at the mature stage enlarged the resorption area markedly and increased pit numbers slightly. Intriguingly, only the number of nuclei per OCL and podosomes increased. These data indicate that AGEs biphasically modulate bone resorption activity of OCLs in a differentiation stage-dependent manner. AGEs at the cell fusion stage reduce bone resorption dramatically, mainly via suppression of RANK expression in osteoclast precursors, whereas AGEs at the mature stage enhance bone resorption slightly, most likely by increasing the number of podosomes in mature OCLs.

  11. Does increased local bone resorption secondary to breast and prostate cancer result in increased cartilage degradation?

    DEFF Research Database (Denmark)

    Leeming, Diana J; Byrjalsen, Inger; Qvist, Per

    2008-01-01

    BACKGROUND: Breast and prostate cancer patients often develop lesions of locally high bone turnover, when the primary tumor metastasizes to the bone causing an abnormal high bone resorption at this site. The objective of the present study was to determine whether local increased bone turnover...... in breast and prostate cancer patients is associated with an increase in cartilage degradation and to test in vitro whether osteoclasts or cathepsin K alone generate CTXII from human bone. METHODS: The study included 132 breast and prostate cancer patient, where presence of bone metastases was graded...... according to the Soloway score. Total bone resorption (CTXItotal) and cartilage degradation (CTXII) were determined. RESULTS: Breast and prostate cancer patients with bone metastases revealed significant increased levels of CTXItotal at Soloway scores 1 and higher compared to patients without bone...

  12. Urine products of bone breakdown as markers of bone resorption and clinical usefulness of urinary hydroxyproline:an overview

    Institute of Scientific and Technical Information of China (English)

    Baris Simsek; (O)zgul Karacaer; inci Karaca

    2004-01-01

    Purpose The purpose of this study is to review the urine products of bone breakdown as markers of bone resorption and usefulness of urinary hydroxyproline. Data Related researches published in 1985 -2000 were systematically reviewed. Results Bone markers could be used for early diagnosis of bone metabolic diseases. Biochemical markers of bone resorption that reflect osteoclast activity and/or collagen degradation provide a new and potentially important clinical tool for the assessment and monitoring of bone metabolism. Assessment of bone resorption can be achieved with measurement of urinary hydroxylysine glycosides, urinary excretion of the collagen pyridinium cross-links, urinary excretion of type I collagen telopeptide breakdown products (cross-linked telopeptides) and urinary hydroxyproline. Conclusion Urinary hydroxyproline has been in use as a marker of bone resorption, but it lacks sensitivity and specificity. It is a modified aminoacid that is a metabolic product of collagen breakdown.Hydroxyproline may be released either free or with fragments of the collagen molecule attached during bone resorption, and it is also liberated by the breakdown of complement and nonskeletal collagen.

  13. Neural crest-mediated bone resorption is a determinant of species-specific jaw length.

    Science.gov (United States)

    Ealba, Erin L; Jheon, Andrew H; Hall, Jane; Curantz, Camille; Butcher, Kristin D; Schneider, Richard A

    2015-12-01

    Precise control of jaw length during development is crucial for proper form and function. Previously we have shown that in birds, neural crest mesenchyme (NCM) confers species-specific size and shape to the beak by regulating molecular and histological programs for the induction and deposition of cartilage and bone. Here we reveal that a hitherto unrecognized but similarly essential mechanism for establishing jaw length is the ability of NCM to mediate bone resorption. Osteoclasts are considered the predominant cells that resorb bone, although osteocytes have also been shown to participate in this process. In adults, bone resorption is tightly coupled to bone deposition as a means to maintain skeletal homeostasis. Yet, the role and regulation of bone resorption during growth of the embryonic skeleton have remained relatively unexplored. We compare jaw development in short-beaked quail versus long-billed duck and find that quail have substantially higher levels of enzymes expressed by bone-resorbing cells including tartrate-resistant acid phosphatase (TRAP), Matrix metalloproteinase 13 (Mmp13), and Mmp9. Then, we transplant NCM destined to form the jaw skeleton from quail to duck and generate chimeras in which osteocytes arise from quail donor NCM and osteoclasts come exclusively from the duck host. Chimeras develop quail-like jaw skeletons coincident with dramatically elevated expression of TRAP, Mmp13, and Mmp9. To test for a link between bone resorption and jaw length, we block resorption using a bisphosphonate, osteoprotegerin protein, or an MMP13 inhibitor, and this significantly lengthens the jaw. Conversely, activating resorption with RANKL protein shortens the jaw. Finally, we find that higher resorption in quail presages their relatively lower adult jaw bone mineral density (BMD) and that BMD is also NCM-mediated. Thus, our experiments suggest that NCM not only controls bone resorption by its own derivatives but also modulates the activity of mesoderm

  14. Normal tempo of bone formation in Turner syndrome despite signs of accelerated bone resorption

    DEFF Research Database (Denmark)

    Cleemann, Line Hartvig; Holm, Kirsten Bagge; Kobbernagel, Hanne;

    2011-01-01

    Aims: To evaluate area bone mineral density (aBMD) and volumetric BMD (vBMD) by dual-energy X-ray absorptiometry, and relations to bone markers and hormones in adolescent women with Turner syndrome (TS). Methods: Cross-sectional study in TS patients (n = 37, 16.7 ± 3.4 years) and control group (n......' TS, compared to controls. vBMD(hip) was lower in 'ongoing GH' TS, but similar in 'previous GH'. z scores for aBMD were uniformly reduced in 'ongoing TS', but near-normalized in 'previous GH' TS. Bone formation and resorption markers were increased in 'ongoing GH' TS, while 'previous GH' TS had...

  15. Normal Tempo of Bone Formation in Turner Syndrome despite Signs of Accelerated Bone Resorption

    DEFF Research Database (Denmark)

    Cleemann, Line; Holm, Kirsten; Kobbernagel, Hanne;

    2011-01-01

    Aims: To evaluate area bone mineral density (aBMD) and volumetric BMD (vBMD) by dual-energy X-ray absorptiometry, and relations to bone markers and hormones in adolescent women with Turner syndrome (TS). Methods: Cross-sectional study in TS patients (n = 37, 16.7 ± 3.4 years) and control group (n......' TS, compared to controls. vBMD(hip) was lower in 'ongoing GH' TS, but similar in 'previous GH'. z scores for aBMD were uniformly reduced in 'ongoing TS', but near-normalized in 'previous GH' TS. Bone formation and resorption markers were increased in 'ongoing GH' TS, while 'previous GH' TS had...

  16. Glucocorticoid-Induced Changes in the Geometry of Osteoclast Resorption Cavities Affect Trabecular Bone Stiffness

    DEFF Research Database (Denmark)

    Vanderoost, Jef; Søe, Kent; Merrild, Ditte Marie Horslev;

    2012-01-01

    Bone fracture risk can increase through bone microstructural changes observed in bone pathologies, such as glucocorticoid-induced osteoporosis. Resorption cavities present one of these microstructural aspects. We recently found that glucocorticoids (GCs) affect the shape of the resorption cavities...... is closely related to the shape of the cavities, highly determines the stiffness effect. The lumbar spine was the anatomic site most affected by the GC-induced changes on the shape of the cavities. These findings might explain the clinical observation that the prevalence of vertebral fractures during GC...

  17. Reduction of nocturnal rise in bone resorption by subcutaneous GLP-2

    DEFF Research Database (Denmark)

    Henriksen, Dennis B; Alexandersen, Peter; Byrjalsen, Inger;

    2004-01-01

    -CTX), a marker of bone resorption. In contrast, GLP-2 was found to have a neutral effect on bone formation, as assessed by serum osteocalcin. Since increased s-CTX levels are normally observed at night, we conducted bedtime studies in healthy postmenopausal women. The objective was to study the effect of GLP-2...

  18. Treatment with Potassium Bicarbonate Lowers Calcium Excretion and Bone Resorption in Older Men and Women

    Science.gov (United States)

    Bicarbonate has been implicated in bone health in older subjects on acid-producing diets in short-term studies. The objective of this study was to determine the effects of potassium bicarbonate and its components on changes in bone resorption and calcium excretion over 3 months in older men and wom...

  19. Resorption of monetite calcium phosphate cement by mouse bone marrow derived osteoclasts.

    Science.gov (United States)

    Montazerolghaem, M; Karlsson Ott, M; Engqvist, H; Melhus, H; Rasmusson, A J

    2015-01-01

    Recently the interest for monetite based biomaterials as bone grafts has increased; since in vivo studies have demonstrated that they are degradable, osteoconductive and improve bone healing. So far osteoclastic resorption of monetite has received little attention. The current study focuses on the osteoclastic resorption of monetite cement using primary mouse bone marrow macrophages, which have the potential to differentiate into resorbing osteoclasts when treated with receptor activator NF-κB ligand (RANKL). The osteoclast viability and differentiation were analysed on monetite cement and compared to cortical bovine bone discs. After seven days live/dead stain results showed no significant difference in viability between the two materials. However, the differentiation was significantly higher on the bone discs, as shown by tartrate resistant acid phosphatase (TRAP) activity and Cathepsin K gene expression. Moreover monetite samples with differentiated osteoclasts had a 1.4 fold elevated calcium ion concentration in their culture media compared to monetite samples with undifferentiated cells. This indicates active resorption of monetite in the presence of osteoclasts. In conclusion, this study suggests that osteoclasts have a crucial role in the resorption of monetite based biomaterials. It also provides a useful model for studying in vitro resorption of acidic calcium phosphate cements by primary murine cells.

  20. Effects of Hydroxyapatite on Bone Graft Resorption in an Experimental Model of Maxillary Alveolar Arch Defects

    Directory of Open Access Journals (Sweden)

    Ozgur Pilanci

    2013-06-01

    Full Text Available Most commonly used treatments use autologous bone grafts to address bony defects in patients with cleft palate. Major disadvantages of autogenous bone grafts include donor site morbidity and resorption. Suggestions to overcome such problems include biomaterials that can be used alone or in combination with bone. We examined the effect of hydroxyapatite cement on bone graft resorption in a rabbit maxillary alveolar defect model. We divided 16 young adult albino New Zealand rabbits into two groups. A defect 1 cm wide was created in each rabbit's maxillary arch. In Group 1, the removed bone was disrupted, and the pieces were replaced in the defect. In the other group, the pieces were replaced after mixing (1:1 with hydroxyapatite cement. Quantitative computed tomographic evaluation of these grafts was performed in axial and coronal planes for each rabbit at 2 and 12 weeks. In axial images at 12 weeks, the group without cement showed mean bone resorption of 15%. In the cement group, a mean volumetric increase of 68% was seen. No resorption occurred when bone grafts were mixed with hydroxyapatite cement. [Arch Clin Exp Surg 2013; 2(3.000: 170-175

  1. Bis-enoxacin blocks rat alveolar bone resorption from experimental periodontitis.

    Directory of Open Access Journals (Sweden)

    Mercedes F Rivera

    Full Text Available Periodontal diseases are multifactorial, caused by polymicrobial subgingival pathogens, including Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. Chronic periodontal infection results in inflammation, destruction of connective tissues, periodontal ligament, and alveolar bone resorption, and ultimately tooth loss. Enoxacin and a bisphosphonate derivative of enoxacin (bis-enoxacin inhibit osteoclast formation and bone resorption and also contain antibiotic properties. Our study proposes that enoxacin and/or bis-enoxacin may be useful in reducing alveolar bone resorption and possibly bacterial colonization. Rats were infected with 10(9 cells of polymicrobial inoculum consisting of P. gingivalis, T. denticola, and T. forsythia, as an oral lavage every other week for twelve weeks. Daily subcutaneous injections of enoxacin (5 mg/kg/day, bis-enoxacin (5, 25 mg/kg/day, alendronate (1, 10 mg/kg/day, or doxycycline (5 mg/day were administered after 6 weeks of polymicrobial infection. Periodontal disease parameters, including bacterial colonization/infection, immune response, inflammation, alveolar bone resorption, and systemic spread, were assessed post-euthanasia. All three periodontal pathogens colonized the rat oral cavity during polymicrobial infection. Polymicrobial infection induced an increase in total alveolar bone resorption, intrabony defects, and gingival inflammation. Treatment with bis-enoxacin significantly decreased alveolar bone resorption more effectively than either alendronate or doxycycline. Histologic examination revealed that treatment with bis-enoxacin and enoxacin reduced gingival inflammation and decreased apical migration of junctional epithelium. These data support the hypothesis that bis-enoxacin and enoxacin may be useful for the treatment of periodontal disease.

  2. Tannerella forsythia GroEL induces inflammatory bone resorption and synergizes with interleukin-17.

    Science.gov (United States)

    Jung, Y-J; Choi, Y-J; An, S-J; Lee, H-R; Jun, H-K; Choi, B-K

    2016-08-03

    Tannerella forsythia is a major periodontal pathogen, and T. forsythia GroEL is a molecular chaperone homologous to human heat-shock protein 60. Interleukin-17 (IL-17) has been implicated in the pathogenesis of periodontitis and several systemic diseases. This study investigated the potential of T. forsythia GroEL to induce inflammatory bone resorption and examined the cooperative effect of IL-17 and T. forsythia GroEL on inflammatory responses. Human gingival fibroblasts (HGFs) and periodontal ligament (PDL) fibroblasts were stimulated with T. forsythia GroEL and/or IL-17. Gene expression of IL-6, IL-8, and cyclooxygenase-2 (COX-2) and concentrations of IL-6, IL-8, and prostaglandin E2 (PGE2 ) were measured by real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assays, respectively. After stimulation of MG63 cells with T. forsythia GroEL and/or IL-17, gene expression of osteoprotegerin (OPG) was examined. After subcutaneous injection of T. forsythia GroEL and/or IL-17 above the calvaria of BALB/c mice, calvarial bone resorption was assessed by micro-computed tomography and histological examination. Tannerella forsythia GroEL induced IL-6 and IL-8 production in HGFs and PDL cells, and IL-17 further promoted IL-6 and IL-8 production. Both T. forsythia GroEL and IL-17 synergistically increased PGE2 production and inhibited OPG gene expression. Calvarial bone resorption was induced by T. forsythia GroEL injection, and simultaneous injection of T. forsythia GroEL and IL-17 further increased bone resorption. These results suggest that T. forsythia GroEL is a novel virulence factor that can contribute to inflammatory bone resorption caused by T. forsythia and synergizes with IL-17 to exacerbate inflammation and bone resorption.

  3. Aging Leads to a Dysregulation in Mechanically Driven Bone Formation and Resorption.

    Science.gov (United States)

    Razi, Hajar; Birkhold, Annette I; Weinkamer, Richard; Duda, Georg N; Willie, Bettina M; Checa, Sara

    2015-10-01

    Physical activity is essential to maintain skeletal mass and structure, but its effect seems to diminish with age. To test the hypothesis that bone becomes less sensitive to mechanical strain with age, we used a combined in vivo/in silico approach. We investigated how maturation and aging influence the mechanical regulation of bone formation and resorption to 2 weeks of noninvasive in vivo controlled loading in mice. Using 3D in vivo morphometrical assessment of longitudinal microcomputed tomography images, we quantified sites in the mouse tibia where bone was deposited or resorbed in response to controlled in vivo loading. We compared the (re)modeling events (formation/resorption/quiescent) to the mechanical strains induced at these sites (predicted using finite element analysis). Mice of all age groups (young, adult, and elderly) responded to loading with increased formation and decreased resorption, preferentially at high strains. Low strains were associated with no anabolic response in adult and elderly mice, whereas young animals showed a strong response. Adult animals showed a clear separation between strain ranges where formation and resorption occurred but without an intermediate quiescent "lazy zone". This strain threshold disappeared in elderly mice, as mechanically induced (re)modeling became dysregulated, apparent in an inability to inhibit resorption or initiate formation. Contrary to what is generally believed until now, aging does not shift the mechanical threshold required to initiate formation or resorption, but rather blurs its specificity. These data suggest that pharmaceutical strategies augmenting physical exercise should consider this dysfunction in the mechanical regulation of bone (re)modeling to more effectively combat age-related bone loss.

  4. Bone resorption is decreased postprandially by intestinal factors and glucagon-like peptide-2 is a possible candidate

    DEFF Research Database (Denmark)

    Holst, Jens Juul; Hartmann, Bolette; Gottschalck, Ida B

    2007-01-01

    -bowel syndrome (SBS) or total gastrectomy in order to elucidate whether the signal for the meal-induced reduction of bone resorption is initiated from the stomach or the intestine. MATERIAL AND METHODS: Bone resorption was assessed from the serum concentration of collagen type I C-telopeptide cross-links (s...

  5. Quantification and visualization of alveolar bone resorption from 3D dental CT images

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Jiro; Mori, Kensaku; Kitasaka, Takayuki; Suenaga, Yasuhito [Nagoya University, Graduate School of Information Science, Nagoya (Japan); Yamada, Shohzoh; Naitoh, Munetaka [Aichi-Gakuin University, School of Dentistry, Nagoya (Japan)

    2007-06-15

    Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

  6. Effect of odanacatib on root resorption and alveolar bone metabolism during orthodontic tooth movement.

    Science.gov (United States)

    Wei, X X; Chu, J P; Zou, Y Z; Ru, N; Cui, S X; Bai, Y X

    2015-12-22

    The aim of this study was to investigate the effect of local administration of odanacatib (ODN) on orthodontic root resorption and the status of alveolar bone metabolism in rat molars. All specimens were scanned using microcomputed tomography and then the raw images were reconstructed. The total volume of the root resorption craters of the 60 g-NS (normal saline) group was higher than in the 60 g-ODN group and the control group. In the 60 g-NS group, the bone volume fraction values of alveolar bone were significantly decreased compared with the other 2 groups. There were no significant differences in the bone volume fraction values of the tibiae among the 3 groups. The results of tartrate-resistant acid phosphatase-positive (TRAP+) numbers showed that there was no difference between the 60 g-NS group and the 60 g-ODN group. The expression of cathepsin K was decreased significantly in the 60 g-ODN group. These results indicate that ODN reduces orthodontics-induced external root resorption and increases alveolar bone metabolism. This may be because ODN inhibits the activity of odontoclasts, but maintains the quantity of odontoclasts and enhances bone formation. ODN promotes local alveolar bone metabolism, but does not affect systemic bone metabolism.

  7. Dioscin inhibits osteoclast differentiation and bone resorption though down-regulating the Akt signaling cascades

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Xinhua; Zhai, Zanjing; Liu, Xuqiang; Li, Haowei [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Ouyang, Zhengxiao [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Department of Orthopaedics, Hunan Provincial Tumor Hospital and Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha (China); Wu, Chuanlong [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Liu, Guangwang [Department of Orthopaedic Surgery, The Central Hospital of Xuzhou, Affiliated Hospital of Medical Collage of Southeast University, Xuzhou (China); Fan, Qiming; Tang, Tingting [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Qin, An, E-mail: dr.qinan@gmail.com [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Dai, Kerong, E-mail: krdai@163.com [Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China)

    2014-01-10

    Highlights: •A natural-derived compound, dioscin, suppresses osteoclast formation and bone resorption. •Dioscin inhibits osteolytic bone loss in vivo. •Dioscin impairs the Akt signaling cascades pathways during osteoclastogenesis. •Dioscin have therapeutic value in treating osteoclast-related diseases. -- Abstract: Bone resorption is the unique function of osteoclasts (OCs) and is critical for both bone homeostasis and pathologic bone diseases including osteoporosis, rheumatoid arthritis and tumor bone metastasis. Thus, searching for natural compounds that may suppress osteoclast formation and/or function is promising for the treatment of osteoclast-related diseases. In this study, we for the first time demonstrated that dioscin suppressed RANKL-mediated osteoclast differentiation and bone resorption in vitro in a dose-dependent manner. The suppressive effect of dioscin is supported by the reduced expression of osteoclast-specific markers. Further molecular analysis revealed that dioscin abrogated AKT phosphorylation, which subsequently impaired RANKL-induced nuclear factor-kappaB (NF-κB) signaling pathway and inhibited NFATc1 transcriptional activity. Moreover, in vivo studies further verified the bone protection activity of dioscin in osteolytic animal model. Together our data demonstrate that dioscin suppressed RANKL-induced osteoclast formation and function through Akt signaling cascades. Therefore, dioscin is a potential natural agent for the treatment of osteoclast-related diseases.

  8. Tibolone inhibits bone resorption without secondary positive effects on cartilage degradation

    Directory of Open Access Journals (Sweden)

    Byrjalsen I

    2008-11-01

    Full Text Available Abstract Background Osteoarthritis is associated with increased bone resorption and increased cartilage degradation in the subchondral bone and joint. The objective of the present study was to determine whether Tibolone, a synthetic steroid with estrogenic, androgenic, and progestogenic properties, would have similar dual actions on both bone and cartilage turnover, as reported previously with some SERMS and HRT. Methods This study was a secondary analysis of ninety-one healthy postmenopausal women aged 52–75 yrs entered a 2-yr double blind, randomized, placebo-controlled study of treatment with either 1.25 mg/day (n = 36, or 2.5 mg/day Tibolone (n = 35, or placebo (n = 20, (J Clin Endocrinol Metab. 1996 Jul;81(7:2419–22 Second void morning urine samples were collected at baseline, and at 3, 6, 12, and 24 months. Urine CrossLaps® ELISA (CTX-I and Urine CartiLaps® ELISA (CTX-II was investigated as markers of bone resorption and cartilage degradation, respectively. Results Tibolone significantly (P Conclusion These data suggest uncoupling of the bone and cartilage effects of the synthetic steroid, Tibolone. Bone resorption was significantly decreased, whereas cartilage degradation was unchanged. These effects are in contrast to those observed some SERMs with effects on both bone and cartilage degradation. These effects may in part be described by the complicated pharmacology of Tibolone on testosterone, estrogen and progesterone receptors.

  9. Effect of glucagon-like peptide-2 exposure on bone resorption

    DEFF Research Database (Denmark)

    Askov-Hansen, Carsten; Jeppesen, Palle B; Lund, Pernille

    2013-01-01

    In healthy subjects, subcutaneous injections of GLP-2 have been shown to elicit dose-related decrease in the bone resorption marker, carboxy-terminal telopeptide of type I collagen (CTX), and have been proposed for the treatment of osteoporosis. This study investigated the relation between GLP-2...

  10. Greater seasonal cycling of 25-hydroxyvitamin D is associated with increased parathyroid hormone and bone resorption

    NARCIS (Netherlands)

    Darling, A L; Hart, K H; Gibbs, M A; Gossiel, F; Kantermann, T; Horton, K; Johnsen, S; Berry, J L; Skene, D J; Eastell, R; Vieth, R; Lanham-New, S A

    2014-01-01

    SUMMARY: This analysis assessed whether seasonal change in 25-hydroxyvitamin D concentration was associated with bone resorption, as evidenced by serum parathyroid hormone and C-terminal telopeptide concentrations. The main finding was that increased seasonal fluctuation in 25-hydroxyvitamin D was a

  11. [Current possibilities of correcting subchondral bone resorption as a major pathogenetic factor for progressive osteoarthrosis].

    Science.gov (United States)

    Naumov, A V

    2014-01-01

    The paper considers the current pathogenesis, by choosing the actual targets of pharmacotherapy with available drugs. It reflects the cytokine mechanisms responsible for lesion of the synovial membranes, cartilage, and subchondral bone. Particular emphasis is laid on the role of chondroitin sulfate, glucosamine, vitamin D3 as drugs that affect the key components of pathogenesis, including the volume of resorptive cavities in the subchondral bone.

  12. Inhibition of bone resorption by the cathepsin K inhibitor odanacatib is fully reversible.

    Science.gov (United States)

    Zhuo, Y; Gauthier, J-Y; Black, W C; Percival, M D; Duong, L T

    2014-10-01

    The cathepsin K (CatK) inhibitor odanacatib (ODN) is currently being developed for the treatment of osteoporosis. In clinical trials, efficacy and resolution of effect of ODN treatment on bone turnover biomarkers and accrued bone mass have been demonstrated. Here, we examine the effects of continuing treatment and discontinuation of ODN versus alendronate (ALN) on osteoclast (OC) function. First, accessibility and reversible engagement of active CatK in intracellular vesicles and resorption lacunae of actively resorbing OCs were demonstrated by the selective and reversible CatK inhibitors, BODIPY-L-226 (IC50=39nM) and L-873,724 (IC50=0.5nM). Next, mature human OCs on bone slices were treated with vehicle, ODN, or ALN for 2days, followed by either continuing with the same treatment, or replacement of the inhibitors by vehicle for additional times as specified per experimental conditions. Maintaining OCs on ODN or ALN significantly reduced CTx-I release compared to vehicle controls. However, only the treatment of OCs with ODN resulted in the formation of small shallow discrete resorption pits, retention of intracellular vesicles enriched with CatK and other lysosomal enzymes, increase in 1-CTP release and number of TRAP(+) OCs. Upon discontinuation of ODN treatment, OCs rapidly resumed bone resorption activity, as demonstrated by a return of OC functional markers (CTx-I, 1-CTP), cell number and size, morphology and number of resorption pits, and vesicular secretion of CatK toward the respective vehicle levels. As expected, discontinuation of ALN did not reverse the treatment-related inhibition of OC activity in the time frame of the experiment. In summary, this study demonstrated rapid kinetics of inhibition and reversibility of the effects of ODN on OC bone resorption, that differentiated the cellular mechanism of CatK inhibition from that of the bisphosphate antiresorptive ALN.

  13. Natural products for treatment of bone erosive diseases: The effects and mechanisms on inhibiting osteoclastogenesis and bone resorption.

    Science.gov (United States)

    An, Jing; Hao, Dingjun; Zhang, Qian; Chen, Bo; Zhang, Rui; Wang, Yi; Yang, Hao

    2016-07-01

    Excessive bone resorption plays a central role on the development of bone erosive diseases, including osteoporosis, rheumatoid arthritis, and periodontitis. Osteoclasts, bone-resorbing multinucleated cells, are differentiated from hemopoietic progenitors of the monocyte/macrophage lineage. Regulation of osteoclast differentiation is considered an effective therapeutic target to the treatment of pathological bone loss. Natural plant-derived products, with potential therapeutic and preventive activities against bone-lytic diseases, have received increasing attention in recent years because of their whole regulative effects and specific pharmacological activities, which are more suitable for long-term use than chemically synthesized medicines. In this review, we summarized the detailed research progress on the active compounds derived from medical plants with potential anti-resorptive effects and their molecular mechanisms on inhibiting osteoclast formation and function. The active ingredients derived from natural plants that are efficacious in suppressing osteoclastogenesis and bone resorption include flavonoids, terpenoids (sesquiterpenoids, diterpenoids, triterpenoids), glycosides, lignans, coumarins, alkaloids, polyphenols, limonoids, quinones and others (steroid, oxoxishhone, fatty acid). Studies have shown that above natural products exert the inhibitory effects via regulating many factors involved in the process of osteoclast differentiation and bone resorption, including the essential cytokines (RANKL, M-CSF), transcription factors (NFATc1, c-Fos), signaling pathways (NF-κB, MAPKs, Src/PI3K/Akt, the calcium ion signaling), osteoclast-specific genes (TRAP, CTSK, MMP-9, integrin β3, OSCAR, DC-STAMP, Atp6v0d2) and local factors (ROS, LPS, NO). The development of osteoclast-targeting natural products is of great value for the prevention or treatment of bone diseases and for bone regenerative medicine.

  14. A theory for bone resorption based on the local rupture of osteocytes cells connections: A finite element study.

    Science.gov (United States)

    Ridha, Hambli; Almitani, Khalid H; Chamekh, Abdessalem; Toumi, Hechmi; Tavares, Joao Manuel R S

    2015-04-01

    In this work, a bone damage resorption finite element model based on the disruption of the inhibitory signal transmitted between osteocytes cells in bone due to damage accumulation is developed and discussed. A strain-based stimulus function coupled to a damage-dependent spatial function is proposed to represent the connection between two osteocytes embedded in the bone tissue. The signal is transmitted to the bone surface to activate bone resorption. The proposed model is based on the idea that the osteocyte signal reduction is not related to the reduction of the stimulus sensed locally by osteocytes due to damage, but to the difficulties for the signal in travelling along a disrupted area due to microcracks that can destroy connections of the intercellular network between osteocytes and bone-lining cells. To check the potential of the proposed model to predict the damage resorption process, two bone resorption mechano-regulation rules corresponding to two mechanotransduction approaches have been implemented and tested: (1) Bone resorption based on a coupled strain-damage stimulus function without ruptured osteocyte connections (NROC); and (2) Bone resorption based on a strain stimulus function with ruptured osteocyte connections (ROC). The comparison between the results obtained by both models, shows that the proposed model based on ruptured osteocytes connections predicts realistic results in conformity with previously published findings concerning the fatigue damage repair in bone.

  15. Effects of Cu2+ and Ph on osteoclastic bone resorption in vitro

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The effects of Cu2+ and pH on osteoclastic bone resorption lacunae are studied by culturing Japanese white rabbit osteoclasts on bone slices. The number and surface area of bone resorption lacunae are measured by photomicrography and image analysis. Concentration of calcium ion in the supernatant is measured by atomic absorption spectrometry to evaluate the activity of osteoclasts. The morphology of the lacunae is observed under a scanning electron microscope. The results indicate that Cu2+ at concentration of 1.00×10-6 mol/L and 1.00×10-7 mol/L inhibits osteoclastic activity and causes a dose-dependent reduction in the number and surface area of the lacunae. While the number of lanunae is increased and osteoclastic bone resorbing function is significantly improved at Cu2+ concentration of 1.00×10-8 mol/L. It is suggested that the effect of Cu2+ on osteoclastic bone resorption depends on Cu2+ concentration. pH had no significant effect on osteoclastic function in the near neutral range.

  16. Bovine parathyroid hormone enhances osteoclast bone resorption by modulating V-ATPase through PTH1R.

    Science.gov (United States)

    Liu, Shuangxin; Zhu, Weiping; Li, Sijia; Ma, Jianchao; Zhang, Huitao; Li, Zhonghe; Zhang, Li; Zhang, Bin; Li, Zhuo; Liang, Xinling; Shi, Wei

    2016-02-01

    The vacuolar-type H+ adenosine triphosphatase (V-ATPase) plays an important role in cellular acidification and bone resorption by osteoclasts. However, the direct effect of bovine parathyroid hormone (bPTH) on V-ATPase has not yet been elucidated. The aim of the present study was to assess the effects of bPTH on V-ATPase and osteoclasts. Osteoclasts from bone marrow (BM)-derived monocytes of C57BL/6 mice were cultured with or without bPTH. The mRNA and protein expression levels of the V-ATPase a3-subunit and d2-subunit (by RT-qPCR and western blot analysis), V-ATPase activity (using the V type ATPase Activity Assay kit) and the bone resorption function of osteoclasts (by bone resorption assay) were examined following treatment with various concentrations of bPTH (0.1, 1.0, 10 and 100 ng/ml) alone or with bPTH and its inhibitor, bafilomycin A1. Furthermore, the expression of parathyroid hormone (PTH) receptors in osteoclasts was also detected. The results revealed that the mRNA and protein expression levels of V-ATPase a3-subunit and d2-subunit increased in a dose‑dependent manner, paralleling the level of bPTH present. In addition, an increase in the concentration of bPTH was accompanied by the increased resorption capability of osteoclasts, whereas bone resorption was inhibited in the presence of bafilomycin A1. In addition, we confirmed the existence of parathyroid hormone 1 receptor (PTH1R) in osteoclasts using three different methods (RT-qPCR, western blot analysis and immunofluorescence staining). We found that bPTH enhanced the bone resorption capability of osteoclasts by modulating the expression of V-ATPase subunits, intracellular acidification and V-ATPase activity. Thus, we propose that PTH has a direct effect on osteoblasts and osteoclasts, and that this effect is mediated through PTH1R, thus contributing to bone remodeling.

  17. In-vivo effect of andrographolide on alveolar bone resorption induced by Porphyromonas gingivalis and its relation with antioxidant enzymes.

    Science.gov (United States)

    Al Batran, Rami; Al-Bayaty, Fouad H; Al-Obaidi, Mazen M Jamil

    2013-01-01

    Alveolar bone resorption is one of the most important facts in denture construction. Porphyromonas gingivalis (Pg) causes alveolar bone resorption, and morphologic measurements are the most frequent methods to identify bone resorption in periodontal studies. This study has aimed at evaluating the effect of Andrographolide (AND) on alveolar bone resorption in rats induced by Pg. 24 healthy male Sprague Dawley rats were divided into four groups as follows: normal control group and three experimental groups challenged orally with Pg ATCC 33277 five times a week supplemented with 20 mg/kg and 10 mg/kg of AND for twelve weeks. Alveolar bones of the left and right sides of the mandible were assessed by a morphometric method. The bone level, that is, the distance from the alveolar bone crest to cementumenamel junction (CEJ), was measured using 6.1 : 1 zoom stereomicroscope and software. AND reduced the effect of Pg on alveolar bone resorption and decreased the serum levels of Hexanoyl-Lysine (HEL); furthermore the reduced glutathione/oxidised glutathione (GSH/GSSG) ratio in AND treated groups (10 and 20 mg/kg) significantly increased when compared with the Pg group (P alveolar bone resorption caused by Pg in rats.

  18. Resorption of bone graft after maxillary sinus grafting and simultaneous implant placement

    OpenAIRE

    Kim, Young-Kyun; Kim, Su-Gwan; Kim, Bum-Su; Jeong, Kyung-In

    2014-01-01

    Objectives The purpose of this study was to evaluate the sinus bone graft resorption over 3 years after two-stage implant placement. Materials and Methods The subjects for this study included 30 patients whose maxillary posterior ridges were too atrophic for implants. Bone-added osteotome sinus floor elevation was used in 15 maxillary sinuses, while the bone graft by lateral approach technique was used in 25 maxillary sinuses. The height from the top of the fixture to the sinus floor was esti...

  19. Screening of protein kinase inhibitors identifies PKC inhibitors as inhibitors of osteoclastic acid secretion and bone resorption

    DEFF Research Database (Denmark)

    Sørensen, Mette G; Henriksen, Kim; Sørensen, Mette Guldmann;

    2010-01-01

    Bone resorption is initiated by osteoclastic acidification of the resorption lacunae. This process is mediated by secretion of protons through the V-ATPase and chloride through the chloride antiporter ClC-7. To shed light on the intracellular signalling controlling extracellular acidification, we...

  20. Quercetin inhibits inflammatory bone resorption in a mouse periodontitis model.

    Science.gov (United States)

    Napimoga, Marcelo H; Clemente-Napimoga, Juliana T; Macedo, Cristina G; Freitas, Fabiana F; Stipp, Rafael N; Pinho-Ribeiro, Felipe A; Casagrande, Rubia; Verri, Waldiceu A

    2013-12-27

    Periodontitis is a disease that leads to bone destruction and represents the main cause of tooth loss in adults. The development of aggressive periodontitis has been associated with increased inflammatory response that is induced by the presence of a subgingival biofilm containing Aggregatibacter actinomycetemcomitans. The flavonoid quercetin (1) is widespread in vegetables and fruits and exhibits many biological properties for possible medical and clinical applications such as its anti-inflamatory and antioxidant effects. Thus, in the present study, the properties of 1 have been evaluated in bone loss and inflammation using a mouse periodontitis model induced by A. actinomycetemcomitans infection. Subcutaneous treatment with 1 reduced A. actinomycetemcomitans-induced bone loss and IL-1β, TNF-α, IL-17, RANKL, and ICAM-1 production in the gingival tissue without affecting bacterial counts. These results demonstrated that quercetin exhibits protective effects in A. actinomycetemcomitans-induced periodontitis in mice by modulating cytokine and ICAM-1 production.

  1. OCLI-023, a Novel Pyrimidine Compound, Suppresses Osteoclastogenesis In Vitro and Alveolar Bone Resorption In Vivo

    Science.gov (United States)

    Kim, Ju Ang; Lee, Doohyun; Kim, Nam Doo; Shin, Hong-In; Bae, Yong Chul; Park, Eui Kyun

    2017-01-01

    An abnormal increase in osteoclast differentiation and activation results in various bone-resorptive diseases, including periodontitis, rheumatoid arthritis, and osteoporosis. Chemical compounds containing pyrimidine ring have been shown to regulate a variety of biological processes. Therefore, in order to identify an antiresorptive agent, we synthesized a series of pyrimidine ring-containing chemical compounds, and found that OCLI-023 suppressed the differentiation and activation of osteoclasts in vitro. OCLI-023 directly inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced differentiation of bone marrow macrophages into osteoclasts, without a cytotoxic response. OCLI-023 also downregulated the RANKL-induced mRNA expression of osteoclast markers as well as inhibited the formation of actin rings and resorption pits. OCLI-023 attenuated the RANKL-induced activation of c-Jun N-terminal kinase and nuclear factor kappa-light-chain-enhancer of activated B cell signaling pathways. In a mouse model of periodontitis, ligature induced an increase of distance between cementoenamel junction (CEJ) and alveolar bone crest (ABC) in the second molar, and OCLI-023 significantly reduced it. Histological analysis showed ligature-induced increase of osteoclast numbers was also significantly reduced by OCLI-023. These data demonstrated the inhibitory effect of OCLI-023 on osteoclast differentiation and activity of osteoclasts in vitro, as well as on ligature-induced bone loss in vivo, and OCLI-023 can be proposed as a novel anti-resorptive compound. PMID:28085946

  2. Alterations in osteoclast function and phenotype induced by different inhibitors of bone resorption - implications for osteoclast quality

    Directory of Open Access Journals (Sweden)

    Leeming Diana J

    2010-06-01

    Full Text Available Abstract Background Normal osteoclasts resorb bone by secretion of acid and proteases. Recent studies of patients with loss of function mutations affecting either of these processes have indicated a divergence in osteoclastic phenotypes. These difference in osteoclast phenotypes may directly or indirectly have secondary effects on bone remodeling, a process which is of importance for the pathogenesis of both osteoporosis and osteoarthritis. We treated human osteoclasts with different inhibitors and characterized their resulting function. Methods Human CD14 + monocytes were differentiated into mature osteoclasts using RANKL and M-CSF. The osteoclasts were cultured on bone in the presence or absence of various inhibitors: Inhibitors of acidification (bafilomycin A1, diphyllin, ethoxyzolamide, inhibitors of proteolysis (E64, GM6001, or a bisphosphonate (ibandronate. Osteoclast numbers and bone resorption were monitored by measurements of TRACP activity, the release of calcium, CTX-I and ICTP, as well as by counting resorption pits. Results All inhibitors of acidification were equally potent with respect to inhibition of both organic and inorganic resorption. In contrast, inhibition of proteolysis by E64 potently reduced organic resorption, but only modestly suppressed inorganic resorption. GM6001 alone did not greatly affect bone resorption. However, when GM6001 and E64 were combined, a complete abrogation of organic bone resorption was observed, without a great effect on inorganic resorption. Ibandronate abrogated both organic and inorganic resorption at all concentrations tested [0.3-100 μM], however, this treatment dramatically reduced TRACP activity. Conclusions We present evidence highlighting important differences with respect to osteoclast function, when comparing the different types of osteoclast inhibitors. Each class of osteoclast inhibitors will lead to different alterations in osteoclast quality, which secondarily may lead to different

  3. Inhibition of Osteoclastogenesis and Bone Resorption in vitro and in vivo by a prenylflavonoid xanthohumol from hops.

    Science.gov (United States)

    Li, Jing; Zeng, Li; Xie, Juan; Yue, Zhiying; Deng, Huayun; Ma, Xueyun; Zheng, Chunbing; Wu, Xiushan; Luo, Jian; Liu, Mingyao

    2015-12-01

    Excessive RANKL signaling leads to superfluous osteoclast formation and bone resorption, is widespread in the pathologic bone loss and destruction. Therefore, targeting RANKL or its signaling pathway has been a promising and successful strategy for this osteoclast-related diseases. In this study, we examined the effects of xanthohumol (XN), an abundant prenylflavonoid from hops plant, on osteoclastogenesis, osteoclast resorption, and RANKL-induced signaling pathway using both in vitro and in vivo assay systems. In mouse and human, XN inhibited osteoclast differentiation and osteoclast formation at the early stage. Furthermore, XN inhibited osteoclast actin-ring formation and bone resorption in a dose-dependent manner. In ovariectomized-induced bone loss mouse model and RANKL-injection-induced bone resorption model, we found that administration of XN markedly inhibited bone loss and resorption by suppressing osteoclast activity. At the molecular level, XN disrupted the association of RANK and TRAF6, resulted in the inhibition of NF-κB and Ca(2+)/NFATc1 signaling pathway during osteoclastogenesis. As a results, XN suppressed the expression of osteoclastogenesis-related marker genes, including CtsK, Nfatc1, Trap, Ctr. Therefore, our data demonstrated that XN inhibits osteoclastogenesis and bone resorption through RANK/TRAF6 signaling pathways. XN could be a promising drug candidate in the treatment of osteoclast-related diseases such as postmenopausal osteoporosis.

  4. Role of carbonic anhydrase in bone resorption induced by 1,25 dihydroxyvitamin D3 in vitro

    Science.gov (United States)

    Hall, G. E.; Kenny, A. D.

    1985-01-01

    The calvaria of 5-to-6-day-old mice treated with 1 x 10 to the -8th M of 1,25(OH)2D3 in vitro for 48 hours are examined in order to study the function of carbonic anhydrase in bone resorption. Calcium concentrations in the culture were measured to assess bone resorption. It is observed that 1,25(OH)2D3 effectively stimulates bone resorption in vitro and the resorption is dose-dependent. The effects of azetazolamide on 1,25(OH)2D3-induced bone resorption are investigated. The data reveal that 1,25(OH)2D3-induced calcium release is associated with an increase in the carbonic anhydrase activity of bone, and bone alkaline phosphatase activity is decreased and acid phosphatase activity is increased in response to 1,25(OH)2D3. A two-fold mechanism for 1,25(OH)2D3-induced bone resorption is proposed; the first mechanism is an indirect activation of osteoclasts and the second involves an interaction between hormone and osteoclast precursors.

  5. Methodology developed for the simultaneous measurement of bone formation and bone resorption in rats based on the pharmacokinetics of fluoride.

    Science.gov (United States)

    Lupo, Maela; Brance, Maria Lorena; Fina, Brenda Lorena; Brun, Lucas Ricardo; Rigalli, Alfredo

    2015-01-01

    This paper describes a novel methodology for the simultaneous estimation of bone formation (BF) and resorption (BR) in rats using fluoride as a nonradioactive bone-seeker ion. The pharmacokinetics of flouride have been extensively studied in rats; its constants have all been characterized. This knowledge was the cornerstone for the underlying mathematical model that we used to measure bone fluoride uptake and elimination rate after a dose of fluoride. Bone resorption and formation were estimated by bone fluoride uptake and elimination rate, respectively. ROC analysis showed that sensitivity, specificity and area under the ROC curve were not different from deoxypiridinoline and bone alkaline phosphatase, well-known bone markers. Sprague-Dawley rats with modified bone remodelling (ovariectomy, hyper, and hypocalcic diet, antiresorptive treatment) were used to validate the values obtained with this methodology. The results of BF and BR obtained with this technique were as expected for each biological model. Although the method should be performed under general anesthesia, it has several advantages: simultaneous measurement of BR and BF, low cost, and the use of compounds with no expiration date.

  6. Metaphyseal and diaphyseal bone loss in the tibia following transient muscle paralysis are spatiotemporally distinct resorption events.

    Science.gov (United States)

    Ausk, Brandon J; Huber, Philippe; Srinivasan, Sundar; Bain, Steven D; Kwon, Ronald Y; McNamara, Erin A; Poliachik, Sandra L; Sybrowsky, Christian L; Gross, Ted S

    2013-12-01

    When the skeleton is catabolically challenged, there is great variability in the timing and extent of bone resorption observed at cancellous and cortical bone sites. It remains unclear whether this resorptive heterogeneity, which is often evident within a single bone, arises from increased permissiveness of specific sites to bone resorption or localized resorptive events of varied robustness. To explore this question, we used the mouse model of calf paralysis induced bone loss, which results in metaphyseal and diaphyseal bone resorption of different timing and magnitude. Given this phenotypic pattern of resorption, we hypothesized that bone loss in the proximal tibia metaphysis and diaphysis occurs through resorption events that are spatially and temporally distinct. To test this hypothesis, we undertook three complimentary in vivo/μCT imaging studies. Specifically, we defined spatiotemporal variations in endocortical bone resorption during the 3weeks following calf paralysis, applied a novel image registration approach to determine the location where bone resorption initiates within the proximal tibia metaphysis, and explored the role of varied basal osteoclast activity on the magnitude of bone loss initiation in the metaphysis using μCT based bone resorption parameters. A differential response of metaphyseal and diaphyseal bone resorption was observed throughout each study. Acute endocortical bone loss following muscle paralysis occurred almost exclusively within the metaphyseal compartment (96.5% of total endocortical bone loss within 6days). Using our trabecular image registration approach, we further resolved the initiation of metaphyseal bone loss to a focused region of significant basal osteoclast function (0.03mm(3)) adjacent to the growth plate. This correlative observation of paralysis induced bone loss mediated by basal growth plate cell dynamics was supported by the acute metaphyseal osteoclastic response of 5-week vs. 13-month-old mice. Specifically

  7. Increased osteoblastogenesis and decreased bone resorption protect against ovariectomy-induced bone loss in thrombospondin-2-null mice.

    Science.gov (United States)

    Hankenson, K D; James, I E; Apone, S; Stroup, G B; Blake, S M; Liang, X; Lark, M W; Bornstein, P

    2005-08-01

    Although bone is composed primarily of extracellular matrix (ECM), the dynamic role that the ECM plays in regulating bone remodeling secondary to estrogen loss is relatively unexplored. Previous studies have shown that mice deficient in the matricellular protein thrombospondin-2 (TSP2-null) form excess endocortical bone; thus, we postulated that enhanced bone formation in TSP2-null mice could protect against ovariectomy (OVX)-induced bone loss. Wild-type (WT) OVX mice showed a significant loss of both midfemoral endocortical and proximal tibial trabecular bone, but OVX did not significantly alter TSP2-null bone. TSP2-null mice showed an increase in bone formation, as indicated by a 70% increase in serum osteocalcin two weeks post OVX and a two-fold increase in bone formation rate (BFR) five weeks post OVX as measured by dynamic histomorphometry. WT animals showed only a 20% increase in serum osteocalcin at two weeks and no change in BFR at five weeks. This increase in bone formation in TSP2-null OVX mice was accompanied by a three-fold increase in osteoprogenitor number. Although these results provide a partial explanation for the maintenance of bone geometry post-OVX, TSP2-null mice five weeks post-OVX also showed a significantly lower level of bone resorption than OVX WT mice, as determined by serum levels of the amino-terminal telopeptide of type I collagen (NTx). We conclude that the absence of TSP2 protects against OVX-induced bone loss by two complementary processes: increased formation and decreased resorption.

  8. Effects of Neuropeptides and Mechanical Loading on Bone Cell Resorption in Vitro

    Directory of Open Access Journals (Sweden)

    Yeong-Min Yoo

    2014-04-01

    Full Text Available Neuropeptides such as vasoactive intestinal peptide (VIP and calcitonin gene-related peptide (CGRP are present in nerve fibers of bone tissues and have been suggested to potentially regulate bone remodeling. Oscillatory fluid flow (OFF-induced shear stress is a potent signal in mechanotransduction that is capable of regulating both anabolic and catabolic bone remodeling. However, the interaction between neuropeptides and mechanical induction in bone remodeling is poorly understood. In this study, we attempted to quantify the effects of combined neuropeptides and mechanical stimuli on mRNA and protein expression related to bone resorption. Neuropeptides (VIP or CGRP and/or OFF-induced shear stress were applied to MC3T3-E1 pre-osteoblastic cells and changes in receptor activator of nuclear factor kappa B (NF-κB ligand (RANKL and osteoprotegerin (OPG mRNA and protein levels were quantified. Neuropeptides and OFF-induced shear stress similarly decreased RANKL and increased OPG levels compared to control. Changes were not further enhanced with combined neuropeptides and OFF-induced shear stress. These results suggest that neuropeptides CGRP and VIP have an important role in suppressing bone resorptive activities through RANKL/OPG pathway, similar to mechanical loading.

  9. Osteoclast-specific inactivation of the Integrin-Linked Kinase (ILK) inhibits bone resorption

    Science.gov (United States)

    Dossa, Tanya; Arabian, Alice; Windle, Jolene J.; Dedhar, Shoukat; Teitelbaum, Steven L.; Ross, F. Patrick; Roodman, G. David; St-Arnaud, René

    2014-01-01

    Bone resorption requires the adhesion of osteoclasts to extracellular matrix (ECM) components, a process mediated by the αvβ3 integrin. Following engagement with the ECM, integrin receptors signal via multiple downstream effectors, including the Integrin-Linked Kinase (ILK). In order to characterize the physiological role of ILK in bone resorption, we generated mice with an osteoclast-specific Ilk gene ablation by mating mice with a floxed Ilk allele with TRAP-Cre transgenic mice. The TRAP-Cre mice specifically excised floxed alleles in osteoclasts, as revealed by crossing them with the ROSA26R reporter strain. Osteoclast-specific Ilk mutant mice appeared phenotypically normal, but histomorphometric analysis of the proximal tibia revealed an increase in bone volume and trabecular thickness. Osteoclast-specific Ilk ablation was associated with an increase in osteoclastogenesis both in vitro and in vivo. However, the mutant osteoclasts displayed a decrease in resorption activity as assessed by reduced pit formation on dentin slices in vitro and decreased serum concentrations of the C-terminal telopeptide of collagen in vivo. Interestingly, compound heterozygous mice in which one allele of Ilk and one allele of the β3 integrin gene were inactivated (ILK+/−; β3+/−) also had increased trabecular thickness, confirming that β3 integrin and Ilk form part of the same genetic cascade. Our results show that ILK is important for the function, but not the differentiation, of osteoclasts. PMID:20564195

  10. Mineral metabolism in isolated mouse long bones: Opposite effects of microgravity on mineralization and resorption

    Science.gov (United States)

    Veldhuijzen, Jean Paul; Vanloon, Jack J. W. A.

    1994-01-01

    An experiment using isolated skeletal tissues under microgravity, is reported. Fetal mouse long bones (metatarsals) were cultured for 4 days in the Biorack facility of Spacelab during the IML-1 (International Microgravity Laboratory) mission of the Space Shuttle. Overall growth was not affected, however glucose consumption was significantly reduced under microgravity. Mineralization of the diaphysis was also strongly reduced under microgravity as compared to the on-board 1 g group. In contrast, mineral resorption by osteoclasts was signficantly increased. These results indicate that these fetal mouse long bones are a sensitive and useful model to further study the cellular mechanisms involved in the changed mineral metabolism of skeletal tissues under microgravity.

  11. Apoptosis-associated uncoupling of bone formation and resorption in osteomyelitis

    Science.gov (United States)

    Marriott, Ian

    2013-01-01

    The mechanisms underlying the destruction of bone tissue in osteomyelitis are only now being elucidated. While some of the tissue damage associated with osteomyelitis likely results from the direct actions of bacteria and infiltrating leukocytes, perhaps exacerbated by bacterial manipulation of leukocyte survival pathways, infection-induced bone loss predominantly results from an uncoupling of the activities of osteoblasts and osteoclasts. Bacteria or their products can directly increase osteoclast formation and activity, and the inflammatory milieu at sites of infection can further promote bone resorption. In addition, osteoclast activity is critically regulated by osteoblasts that can respond to bacterial pathogens and foster both inflammation and osteoclastogenesis. Importantly, bone loss during osteomyelitis is also brought about by a decline in new bone deposition due to decreased bone matrix synthesis and by increased rates of osteoblast apoptosis. Extracellular bacterial components may be sufficient to reduce osteoblast viability, but the causative agents of osteomyelitis are also capable of inducing continuous apoptosis of these cells by activating intrinsic and extrinsic cell death pathways to further uncouple bone formation and resorption. Interestingly, bacterial internalization appears to be required for maximal osteoblast apoptosis, and cytosolic inflammasome activation may act in concert with autocrine/paracrine death receptor-ligand signaling to induce cell death. The manipulation of apoptotic pathways in infected bone cells could be an attractive new means to limit inflammatory damage in osteomyelitis. However, the mechanism that is the most important in bacterium-induced bone loss has not yet been identified. Furthermore, it remains to be determined whether the host would be best served by preventing osteoblast cell death or by promoting apoptosis in infected cells. PMID:24392356

  12. Screening of protein kinase inhibitors identifies PKC inhibitors as inhibitors of osteoclastic acid secretion and bone resorption

    Directory of Open Access Journals (Sweden)

    Boutin Jean A

    2010-10-01

    Full Text Available Abstract Background Bone resorption is initiated by osteoclastic acidification of the resorption lacunae. This process is mediated by secretion of protons through the V-ATPase and chloride through the chloride antiporter ClC-7. To shed light on the intracellular signalling controlling extracellular acidification, we screened a protein kinase inhibitor library in human osteoclasts. Methods Human osteoclasts were generated from CD14+ monocytes. The effect of different kinase inhibitors on lysosomal acidification in human osteoclasts was investigated using acridine orange for different incubation times (45 minutes, 4 and 24 hours. The inhibitors were tested in an acid influx assay using microsomes isolated from human osteoclasts. Bone resorption by human osteoclasts on bone slices was measured by calcium release. Cell viability was measured using AlamarBlue. Results Of the 51 compounds investigated only few inhibitors were positive in both acidification and resorption assays. Rottlerin, GF109203X, Hypericin and Ro31-8220 inhibited acid influx in microsomes and bone resorption, while Sphingosine and Palmitoyl-DL-carnitine-Cl showed low levels of inhibition. Rottlerin inhibited lysosomal acidification in human osteoclasts potently. Conclusions In conclusion, a group of inhibitors all indicated to inhibit PKC reduced acidification in human osteoclasts, and thereby bone resorption, indicating that acid secretion by osteoclasts may be specifically regulated by PKC in osteoclasts.

  13. Toll-Like Receptor 2 Stimulation of Osteoblasts Mediates Staphylococcus Aureus Induced Bone Resorption and Osteoclastogenesis through Enhanced RANKL

    Science.gov (United States)

    Kassem, Ali; Lindholm, Catharina; Lerner, Ulf H

    2016-01-01

    Severe Staphylococcus aureus (S. aureus) infections pose an immense threat to population health and constitute a great burden for the health care worldwide. Inter alia, S. aureus septic arthritis is a disease with high mortality and morbidity caused by destruction of the infected joints and systemic bone loss, osteoporosis. Toll-Like receptors (TLRs) are innate immune cell receptors recognizing a variety of microbial molecules and structures. S. aureus recognition via TLR2 initiates a signaling cascade resulting in production of various cytokines, but the mechanisms by which S. aureus causes rapid and excessive bone loss are still unclear. We, therefore, investigated how S. aureus regulates periosteal/endosteal osteoclast formation and bone resorption. S. aureus stimulation of neonatal mouse parietal bone induced ex vivo bone resorption and osteoclastic gene expression. This effect was associated with increased mRNA and protein expression of receptor activator of NF-kB ligand (RANKL) without significant change in osteoprotegerin (OPG) expression. Bone resorption induced by S. aureus was abolished by OPG. S. aureus increased the expression of osteoclastogenic cytokines and prostaglandins in the parietal bones but the stimulatory effect of S. aureus on bone resorption and Tnfsf11 mRNA expression was independent of these cytokines and prostaglandins. Stimulation of isolated periosteal osteoblasts with S. aureus also resulted in increased expression of Tnfsf11 mRNA, an effect lost in osteoblasts from Tlr2 knockout mice. S. aureus stimulated osteoclastogenesis in isolated periosteal cells without affecting RANKL-stimulated resorption. In contrast, S. aureus inhibited RANKL-induced osteoclast formation in bone marrow macrophages. These data show that S. aureus enhances bone resorption and periosteal osteoclast formation by increasing osteoblast RANKL production through TLR2. Our study indicates the importance of using different in vitro approaches for studies of how S

  14. {sup 3}H-tetracycline as a proxy for {sup 41}Ca for measuring dietary perturbations of bone resorption

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Connie [Department of Foods and Nutrition, Purdue University, 700 W. State Street, West Lafayette, IN 47906-2059 (United States)]. E-mail: weavercm@purdue.edu; Cheong, Jennifer [Department of Foods and Nutrition, Purdue University, 700 W. State Street, West Lafayette, IN 47906-2059 (United States); Jackson, George [PRIME Lab, Purdue University, West Lafayette, IN (United States); Elmore, David [PRIME Lab, Purdue University, West Lafayette, IN (United States); McCabe, George [Statistics, Purdue University, West Lafayette, IN (United States); Martin, Berdine [Department of Foods and Nutrition, Purdue University, 700 W. State Street, West Lafayette, IN 47906-2059 (United States)

    2007-06-15

    Our group is interested in evaluating early effects of dietary interventions on bone loss. Postmenopausal women lose bone following reduction in estrogen which leads to increased risk of fracture. Traditional means of monitoring bone loss and effectiveness of treatments include changes in bone density, which takes 6 months to years to observe effects, and changes in biochemical markers of bone turnover, which are highly variable and lack specificity. Prelabeling bone with {sup 41}Ca and measuring urinary {sup 41}Ca excretion with accelerator mass spectrometry provides a sensitive, specific, and rapid approach to evaluating effectiveness of treatment. To better understand {sup 41}Ca technology as a tool for measuring effective treatments on reducing bone resorption, we perturbed bone resorption by manipulating dietary calcium in rats. We used {sup 3}H-tetracycline ({sup 3}H-TC) as a proxy for {sup 41}Ca and found that a single dose is feasible to study bone resorption. Suppression of bone resorption, as measured by urinary {sup 3}H-TC, by dietary calcium was observed in rats stabilized after ovariectomy, but not in recently ovariectomized rats.

  15. 3H-tetracycline as a proxy for 41Ca for measuring dietary perturbations of bone resorption

    Science.gov (United States)

    Weaver, Connie; Cheong, Jennifer; Jackson, George; Elmore, David; McCabe, George; Martin, Berdine

    2007-06-01

    Our group is interested in evaluating early effects of dietary interventions on bone loss. Postmenopausal women lose bone following reduction in estrogen which leads to increased risk of fracture. Traditional means of monitoring bone loss and effectiveness of treatments include changes in bone density, which takes 6 months to years to observe effects, and changes in biochemical markers of bone turnover, which are highly variable and lack specificity. Prelabeling bone with 41Ca and measuring urinary 41Ca excretion with accelerator mass spectrometry provides a sensitive, specific, and rapid approach to evaluating effectiveness of treatment. To better understand 41Ca technology as a tool for measuring effective treatments on reducing bone resorption, we perturbed bone resorption by manipulating dietary calcium in rats. We used 3H-tetracycline (3H-TC) as a proxy for 41Ca and found that a single dose is feasible to study bone resorption. Suppression of bone resorption, as measured by urinary 3H-TC, by dietary calcium was observed in rats stabilized after ovariectomy, but not in recently ovariectomized rats.

  16. Early resorption of an artificial bone graft made of calcium phosphate for cranioplasty: case report

    Directory of Open Access Journals (Sweden)

    Monaco BA

    2013-11-01

    Full Text Available Bernardo Assumpção de Monaco, Erich Talamoni Fonoff, Manoel Jacobsen TeixeiraDivision of Functional Neurosurgery, Department of Neurology, Hospital das Clinicas, University of São Paulo Medical School, São Paulo, BrazilAbstract: The treatment of uncomplicated osteoma consists of an en bloc resection, or curettage, of the tumor, followed by cranioplasty. Here, we present a case report of a patient treated for a parietal osteoma, followed by a calcium phosphate cranioplasty, with early resorption after 3 months, which was presented by a sinking flap above the resection area. This case suggests that synthetic cranioplasty should be preferred, even in small skull-gap areas.Keywords: cranioplasty, bone cement, osteoma, calcium phosphate, resorption

  17. Study on bone resorption behavior of osteoclast under drug effect using {sup 41}Ca tracing

    Energy Technology Data Exchange (ETDEWEB)

    Dong Kejun [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Lu Liyan [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); CNNC Third Qinshan Nuclear Power Co. Ltd., Haiyan 314300 (China); He Ming; Ouyang Yinggen; Xue Yan; Li Chaoli; Wu Shaoyong [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Wang Xianggao [College of Physics Science and Technology, Guangxi University, Nanning 530004 (China); Shen Hongtao [College of Physics and Technology, Guangxi Normal University, Guilin 541004 (China); Gao Jianjun [Institute of Radiation Medicine, Fudan University, Shanghai 200032 (China); Wang Wei [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); China National Nuclear Corporation, Beijing 100822 (China); Chen Dafu; Xing Yonggang [Beijing Research Institute of Traumatology and Orthopaedics, Beijing 100035 (China); Jian, Yuan [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China); Jiang Shan, E-mail: jiangs@ciae.ac.cn [China Institute of Atomic Energy, P.O. Box 275(50), Beijing 102413 (China)

    2013-01-15

    The mechanisms governing calcium fluxes during bone remodeling processes in Osteoporosis (OP) patients are poorly known. Understanding the changes of Osteoclasts (OC) during this dynamic transition is important to prevent and cure OP. The exploration of long-lived {sup 41}Ca (T{sub 1/2} = 1.04 Multiplication-Sign 10{sup 5} years) tracer combined with AMS measurements leads to the possibility of monitoring the bone resorption behavior of OC in OP patients. In this work, the behavior of OC with the administration of Strontium Ranelate (SR), a drug for OP, was studied by using {sup 41}Ca labeled hydroxyapatite (HAP) to simulate the bone. AMS on the HI-13 tandem accelerator at CIAE was used to determine trace amounts of {sup 41}Ca. The results show that the technique of {sup 41}Ca tracing with AMS can be used to quantitatively monitor the behavior of OC in bone resorption under the effects of drugs. Experimental details and preliminary results will be presented.

  18. The inhibitory effect of vitamin K on RANKL-induced osteoclast differentiation and bone resorption.

    Science.gov (United States)

    Wu, Wei-Jie; Kim, Min Seuk; Ahn, Byung-Yong

    2015-10-01

    To further understand the correlation between vitamin K and bone metabolism, the effects of vitamins K1, menaquinone-4 (MK-4), and menaquinone-7 (MK-7) on RANKL-induced osteoclast differentiation and bone resorption were comparatively investigated. Vitamin K2 groups (MK-4 and MK-7) were found to significantly inhibit RANKL-medicated osteoclast cell formation of bone marrow macrophages (BMMs) in a dose-dependent manner, without any evidence of cytotoxicity. The mRNA expression of specific osteoclast differentiation markers, such as c-Fos, NFATc1, OSCAR, and TRAP, as well as NFATc1 protein expression and TRAP activity in RANKL-treated BMMs were inhibited by vitamin K2, although MK-4 exhibited a significantly greater efficiency compared to MK-7. In contrast, the same dose of vitamin K1 had no inhibitory effect on RANKL-induced osteoclast cell formation, but increased the expression of major osteoclastogenic genes. Interestingly, vitamins K1, MK-4 and MK-7 all strongly inhibited osteoclastic bone resorption (p vitamins K1, MK-4 and MK-7 have anti-osteoporotic properties, while their regulation effects on osteoclastogenesis are somewhat different.

  19. Follicle-stimulating hormone enhances alveolar bone resorption via upregulation of cyclooxygenase-2

    Science.gov (United States)

    Zhu, Chunxia; Ji, Yaoting; Liu, Shengbo; Bian, Zhuan

    2016-01-01

    This study aimed to investigate whether follicle-stimulating hormone (FSH)-induced alveolar bone resorption was mediated by a cyclooxygenase 2 (COX-2) enzyme related mechanism. Experimental periodontitis was induced in bilateral ovariectomized (OVX) rats, some of which were injected with triptorelin, an FSH inhibitor. After mandibles were collected, we performed micro-computed tomography to evaluate alveolar bone loss and immunohistochemical staining to assess COX-2 expression. As well, human periodontal ligament cells (PDLCs) were treated with FSH (30 ng/ml), and the COX-2 mRNA and protein expression levels were measured by quantitative real-time polymerase chain reaction (qPCR) and Western blotting, respectively; prostaglandin E2 (PGE2) levels were measured by enzyme-linked immunosorbent assay (ELISA). The results indicated that FSH significantly increased alveolar bone resorption and the expression of COX-2 in the bilateral OVX + Ligatured rats compared with the other treatment groups. FSH also increased the mRNA and protein expression of COX-2 and PGE2 (P < 0.01) in human PDLCs. Further, the analysis of signaling pathways revealed the activation of COX-2-mediated pathways including Erk, p38, and Akt. These data suggest that FSH aggravates alveolar bone loss via a COX-2-upregulation mechanism and that the Erk, p38, and Akt pathways are involved in this pathological process. PMID:27725865

  20. Influences of Fucoxanthin on Alveolar Bone Resorption in Induced Periodontitis in Rat Molars.

    Science.gov (United States)

    Kose, Oguz; Arabaci, Taner; Yemenoglu, Hatice; Kara, Adem; Ozkanlar, Seckin; Kayis, Sevki; Duymus, Zeynep Yesil

    2016-03-30

    The aim of this study was to evaluate the effects of systemic fucoxanthin treatment on alveolar bone resorption in rats with periodontitis. Thirty rats were divided into control, experimental periodontitis (EP), and experimental periodontitis-fucoxanthin (EP-FUCO) groups. Periodontitis was induced by ligature for four weeks. After removal of the ligature, the rats in the EP-FUCO group were treated with a single dose of fucoxanthin (200 mg/kg bw) per day for 28 consecutive days. At the end of the study, all of the rats were euthanized and intracardiac blood and mandible tissue samples were obtained for biochemical, immunohistochemical, and histometric analyses. Fucoxanthin treatment resulted in a slight decrease in tumor necrosis factor-α, interleukin-1β, and interleukin-6 levels and a significant decrease in oxidative stress index. It was observed that fucoxanthin caused a significant reduction in receptor activator of nuclear factor kappa-β ligand (RANKL) levels and a statistically non-significant elevation in osteoprotegerin and bone-alkaline phosphatase levels. There were no significant differences in alveolar bone loss levels between the EP and EP-FUCO groups. This experimental study revealed that fucoxanthin provides a limited reduction in alveolar bone resorption in rats with periodontitis. One of the mechanisms underlying the mentioned limited effect might be related to the ability of fucoxanthin to inhibit oxidative stress-related RANKL-mediated osteoclastogenesis.

  1. Effects of epidermal growth factor on bone formation and resorption in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Marie, P.J.; Hott, M.; Perheentupa, J. (Institut National de la Sante et de la Recherche Medicale, Paris (France))

    1990-02-01

    The effects of mouse epidermal growth factor (EGF) on bone formation and resorption were examined in male mice. EGF administration (2-200 ng.g-1.day-1 ip for 7 days) induced a dose-dependent rise in plasma EGF levels that remained within physiological range. Histomorphometric analysis of caudal vertebrae showed that EGF (20 and 200 ng.g-1.day-1) reduced the endosteal matrix and mineral appositional rates after 5 days of treatment as measured by double (3H)proline labeling and double tetracycline labeling, respectively. This effect was transitory and was not observed after 7 days of EGF administration. EGF administered for 7 days induced a dose-dependent increase in the periosteal osteoblastic and tetracycline double-labeled surfaces. At high dosage (200 ng.g-1.day-1) EGF administration increased the osteoclastic surface and the number of acid phosphatase-stained osteoclasts, although plasma calcium remained normal. The results show that EGF administration at physiological doses induces distinct effects on endosteal and periosteal bone formation and that the effects are dependent on EGF dosage and duration of treatment. This study indicates that EGF at physiological dosage stimulates periosteal bone formation and increases endosteal bone resorption in the growing mouse.

  2. From histology to micro-CT: Measuring and modeling resorption cavities and their relation to bone competence.

    Science.gov (United States)

    Vanderoost, Jef; van Lenthe, G Harry

    2014-09-28

    The process of bone remodelling plays an essential role in the emergence and maintenance of bone geometry and its internal structure. Osteoclasts are one of the three main bone cell types that play a crucial role in the bone remodelling cycle. At the microstructural level, osteoclasts create bone deficits by eroding resorption cavities. Understanding how these cavities impair the mechanical quality of the bone is not only relevant in quantifying the impact of resorption cavities in healthy bone and normal aging, but maybe even more so in quantifying their role in metabolic bone diseases. Metabolic bone diseases and their treatment are both known to affect the bone remodelling cycle; hence, the bone mechanical competence can and will be affected. However, the current knowledge of the precise dimensions of these cavities and their effect on bone competence is rather limited. This is not surprising considering the difficulties in deriving three-dimensional (3D) properties from two-dimensional (2D) histological sections. The measurement difficulties are reflected in the evaluation of how resorption cavities affect bone competence. Although detailed 3D models are generally being used to quantify the mechanical impact of the cavities, the representation of the cavities themselves has basically been limited to simplified shapes and averaged cavity properties. Qualitatively, these models indicate that cavity size and location are important, and that the effect of cavities is larger than can be expected from simple bone loss. In summary, the dimensions of osteoclast resorption cavities were until recently estimated from 2D measures; hence, a careful interpretation of resorption cavity dimensions is necessary. More effort needs to go into correctly quantifying resorption cavities using modern 3D imaging techniques like micro-computed tomography (micro-CT) and synchrotron radiation CT. Osteoclast resorption cavities affect bone competence. The structure-function relationships

  3. Effect of RGD-insulin on activities of bone resorption and the possible mechanism in human osteoclast-like cells in vitro.

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective: In this study, we explored the mechanism of anti-bone resorption of RGD-insulin using osteoclastlike cells(OLCs) from giant cell tumor of bone as an in vitro model. Methods: The function of bone resorption was observed and the staining for tartrate-resistant acid

  4. The effect of semelil (angipars® on bone resorption and bone formation markers in type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Hasani-Ranjbar Shirin

    2012-12-01

    Full Text Available Abstract Background and purpose of the study Diabetes mellitus has been recognized as a major risk factor for osteoporosis in which bone turnover is affected by different mechanisms. As the morbidity, mortality and financial cost related to osteoporosis are expected to rise in Iran in coming years, and considering the efficacy of Angipars® for improvement of different ulcers which made it a new herbal drug in diabetic foot ulcer, there is a need to evaluate the effect of this new drug on different organs including bone resorption and bone formation markers. Methods In this randomized, double- blind clinical trial, 61 diabetic patients were included. The subjects were randomly divided into intervention and control groups. Subjects of intervention group received 100 mg of Angipars® twice a day. Laboratory tests including bone resorption and bone formation markers were performed at baseline and after 3 months. Result 31 patients in study group and 30 patients in control group finished the study. The mean age of the study population and the mean disease duration was respectively 51.8 ± 6.2 and 7.5 ± 4.7 years with no significant differences between intervention and control patients. No statistically significant differences between patients and controls were observed in pyridinoline, osteocalcin, urine calcium, bone alkaline phosphatase and tumor necrosis factor (TNF-α. Only urine creatinine level significantly changed between two groups after 3 month of treatment (p-value: 0.029 Conclusion In conclusion, the findings of this study indicate that Semelil (Angipars® had no beneficial or harmful effects on bone. It might be other effects of this new component on bone turnover process which need more studies and more time to be discovered.

  5. Bone resorption and environmental exposure to cadmium in children: a cross - sectional study

    Directory of Open Access Journals (Sweden)

    Sughis Muhammad

    2011-12-01

    Full Text Available Abstract Background Exposure to cadmium has been associated with osteoporosis and fracture risk in women and elderly, but studies in children are lacking. In the present study we investigate the association between markers of bone demineralization [urinary calcium (Ca and deoxypyridinoline (DPD excretion] and urinary cadmium (Cd excretion (as an index of lifetime body burden. Methods 155 schoolchildren from 2 elementary schools in Lahore, Pakistan were included. Urinary Cd was measured as an index of lifetime exposure. We assessed the multivariate-adjusted association of exposure with markers of bone resorption, urinary DPD as well as with Ca excretion. Results Urinary Cd averaged 0.50 nmol/mmol creatinine and was not influenced by age, height, weight and socio-economic status (SES. Independent of gender, age, height, weight and SES a doubling of urinary Cd was associated with a 1.72 times (p Conclusions Even in young children, low-level environmental exposure to cadmium is associated with evidence of bone resorption, suggesting a direct osteotoxic effect with increased calciuria. These findings might have clinical relevance at older age.

  6. Comparison of Bone Resorption Rates after Intraoral Block Bone and Guided Bone Regeneration Augmentation for the Reconstruction of Horizontally Deficient Maxillary Alveolar Ridges.

    Science.gov (United States)

    Gultekin, B Alper; Bedeloglu, Elcin; Kose, T Emre; Mijiritsky, Eitan

    2016-01-01

    Purpose. Bone atrophy after tooth loss may leave insufficient bone for implant placement. We compared volumetric changes after autogenous ramus block bone grafting (RBG) or guided bone regeneration (GBR) in horizontally deficient maxilla before implant placement. Materials and Methods. In this retrospective study, volumetric changes at RBG or GBR graft sites were evaluated using cone-beam computed tomography. The primary outcome variable was the volumetric resorption rate. Secondary outcomes were bone gain, graft success, and implant insertion torque. Results. Twenty-four patients (28 grafted sites) were included (GBR, 15; RBG, 13). One patient (RBG) suffered mucosal dehiscence at the recipient site 6 weeks after surgery, which healed spontaneously. Mean volume reduction in the GBR and RBG groups was 12.48 ± 2.67% and 7.20 ± 1.40%, respectively. GBR resulted in significantly more bone resorption than RBG (P 0.05). Conclusions. Both RBG and GBR hard-tissue augmentation techniques provide adequate bone graft volume and stability for implant insertion. However, GBR causes greater resorption at maxillary augmented sites than RBG, which clinicians should consider during treatment planning.

  7. Inhibited osteoblastogenesis, enhanced bone resorption and disrupted vitamin d3 homeostasis in female c57bl/6 mice fed alcohol

    Science.gov (United States)

    Alcohol abuse is a well-known factor for increased risk of osteoporosis. Previous studies have shown that molecular mechanisms underlying alcohol-induced bone loss are complex, involving direct effects on both bone formation and resorption and additional indirect actions via endocrine disruption. Wh...

  8. Reduction in bone resorption by exogenous glucagon-like peptide-2 administration requires an intact gastrointestinal tract

    DEFF Research Database (Denmark)

    Gottschalck, Ida B; Jeppesen, Palle B; Holst, Jens Juul

    2008-01-01

    OBJECTIVE: Biochemical markers for bone resorption (s-CTX) are reduced by food intake, whereas markers for bone formation seem to be unaffected by meal status. Glucagon-like peptide-2 (GLP-2) is a peptide secreted from endocrine L cells in the intestinal mucosa in relation to food-intake. Subcuta...

  9. Influence of Baicalin on Alveolar Bone Resorption in Rat Experimental Periodontitis

    OpenAIRE

    Chen, Yue; Wu, Zhi-Fen; YANG, Lian-Jia

    2008-01-01

    Objective: In this study, the effects of baicalin – a flavonoid purified from Scutellaria baicalensis. Georgi, Scutellaria L. – on alveolar bone resorption in rat experimental periodontitis were examined. Method: 12 Sprague-Dawley rats (SD rats) were randomly divided into four groups: Group A1, A2, B and C. Except for Group C – the control group–, Group A1, A2 and B were used to establish the rat periodontitis model by repeat injection of Lipopolysaccharide (LPS). At the same time, Group A1 a...

  10. Computational biomechanics of bone's responses to dental prostheses - osseointegration, remodeling and resorption

    Science.gov (United States)

    Li, Wei; Rungsiyakull, Chaiy; Field, Clarice; Lin, Daniel; Zhang, Leo; Li, Qing; Swain, Michael

    2010-06-01

    Clinical and experimental studies showed that human bone has the ability to remodel itself to better adapt to its biomechanical environment by changing both its material properties and geometry. As a consequence of the rapid development and extensive applications of major dental restorations such as implantation and fixed partial denture (FPD), the effect of bone remodeling on the success of a dental restorative surgery is becoming critical for prosthetic design and pre-surgical assessment. This paper aims to provide a computational biomechanics framework to address dental bone's responses as a result of dental restoration. It explored three important issues of resorption, apposition and osseointegration in terms of remodeling simulation. The published remodeling data in long bones were regulated to drive the computational remodeling prediction for the dental bones by correlating the results to clinical data. It is anticipated that the study will provide a more predictive model of dental bone response and help develop a new design methodology for patient-specific dental prosthetic restoration.

  11. Decreased bone turnover with balanced resorption and formation prevent cortical bone loss during disuse (hibernation) in grizzly bears (Ursus arctos horribilis).

    Science.gov (United States)

    McGee, Meghan E; Maki, Aaron J; Johnson, Steven E; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2008-02-01

    Disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. However, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. Here we show decreased cortical bone turnover during hibernation with balanced formation and resorption in grizzly bear femurs. Hibernating grizzly bear femurs were less porous and more mineralized, and did not demonstrate any changes in cortical bone geometry or whole bone mechanical properties compared to active grizzly bear femurs. The activation frequency of intracortical remodeling was 75% lower during hibernation than during periods of physical activity, but the normalized mineral apposition rate was unchanged. These data indicate that bone turnover decreases during hibernation, but osteons continue to refill at normal rates. There were no changes in regional variation of porosity, geometry, or remodeling indices in femurs from hibernating bears, indicating that hibernation did not preferentially affect one region of the cortex. Thus, grizzly bears prevent bone loss during disuse by decreasing bone turnover and maintaining balanced formation and resorption, which preserves bone structure and strength. These results support the idea that bears possess a biological mechanism to prevent disuse osteoporosis.

  12. Dehydroepiandrosterone Inhibited the Bone Resorption through the Upregulation of OPG/RANKL

    Institute of Scientific and Technical Information of China (English)

    Yudong Wang; Ling Wang; Dajin Li; Wenjun Wang

    2006-01-01

    The plasma level of dehydroepiandrosterone (DHEA) is decreases gradually along with aging. The beneficial effects of DHEA as an anti-aging steroid, such as the stimulatory effect on immune system, anti-diabetes mellitus,anti-atherosclerosis, anti-dementia, anti-obesity and anti-osteoporosis have been demonstrated in experiment both in vitro and in vivo. It is important to investigate the effective mechanism of DHEA in therapeutics for postmenopausal osteoporosis. Having isolated and cultured osteoblasts (Obs) and osteoclasts (Ocs), we analysed the effect of DHEA on osteoblastic viability, regulation of DHEA on the expression of osteoprotegerin(OPG)/receptor activator of NF-κB ligand (RANKL) mRNA in Obs, and then observed the action of DHEA on bone resorption of Ocs in the presence or absence of Obs. The results showed that DHEA improved viability of Obs within the concentration range of 10-8-10-6 M, especially at the concentration of 10-7 M. DHEA could apparently increase the ratio of OPG/RANKL mRNA in Obs. In the presence of Obs, DHEA could decrease the number and area of absorption lacuna of specula. We concluded, therefore, only in the presence of Obs, DHEA could inhibit the bone resorption of Ocs, which may be mediated by OPG/RANKL of Obs.

  13. Reduction of bone resorption by the application of fibrin glue in the reconstruction of the alveolar cleft.

    Science.gov (United States)

    Segura-Castillo, José L; Aguirre-Camacho, Humberto; González-Ojeda, Alejandro; Michel-Perez, Jorge

    2005-01-01

    A major complication in 30% to 75% of cases of surgical treatment of alveolar cleft is resorption of the bone graft. A treatment alternative is the application of fibrin glue, which has the capacity to favor the integration of the graft. The main objective of the study was to evaluate if the use of the fibrin glue reduces bone resorption when it is applied locally. The authors designed a randomized clinical trial. Patients were divided into two groups: group 1, fibrin glue; and group 2, control. Pre- and postoperative graft volume, bone density, bone quality (Lekholm and Zarb, and Norton and Gamble classifications), and postoperative complications were evaluated. The follow-up for all patients was 3 months after discharge. Twenty-seven patients were surgically treated, 13 in group 1 and 14 in group 2. Group 1 had increased graft volume compared with group 2 (64.32 cm v 21.70 cm; P 0.076). Bone quality was type 1, 2 and 3 and 4 in group 1. Resorption in group 2 was 62.26%; in group 1, it was 29.72% (P > 0.081). The observed complications were infection and dehiscence of sutures (P > 0.537). The authors conclude that the fibrin glue significantly diminishes bone resorption, allowing improved graft integration and quality.

  14. From histology to micro-CT:Measuring and modeling resorption cavities and their relation to bone competence

    Institute of Scientific and Technical Information of China (English)

    Jef; Vanderoost; G; Harry; van; Lenthe

    2014-01-01

    The process of bone remodelling plays an essential role in the emergence and maintenance of bone geometry and its internal structure.Osteoclasts are one of the three main bone cell types that play a crucial role in the bone remodelling cycle.At the microstructural level,osteoclasts create bone deficits by eroding resorption cavities.Understanding how these cavities impair the mechanical quality of the bone is not only relevant in quantifying the impact of resorption cavities in healthy bone and normal aging,but maybe even more so in quantifying their role in metabolic bone diseases.Meta-bolic bone diseases and their treatment are both known to affect the bone remodelling cycle;hence,the bone mechanical competence can and will be affected.How-ever,the current knowledge of the precise dimensions of these cavities and their effect on bone competence is rather limited.This is not surprising considering the difficulties in deriving three-dimensional(3D)properties from two-dimensional(2D)histological sections.The measurement difficulties are reflected in the evalua-tion of how resorption cavities affect bone competence.Although detailed 3D models are generally being used to quantify the mechanical impact of the cavities,the representation of the cavities themselves has basicallybeen limited to simplified shapes and averaged cavityproperties.Qualitatively,these models indicate that cav-ity size and location are important,and that the effectof cavities is larger than can be expected from simplebone loss.In summary,the dimensions of osteoclastresorption cavities were until recently estimated from2D measures;hence,a careful interpretation of resorp-tion cavity dimensions is necessary.More effort needsto go into correctly quantifying resorption cavities usingmodern 3D imaging techniques like micro-computedtomography(micro-CT)and synchrotron radiation CT.Osteoclast resorption cavities affect bone competence.The structure-function relationships have been ana-lysed using

  15. Inhibition of bone resorption by Tanshinone VI isolated from Salvia miltiorrhiza Bunge

    Directory of Open Access Journals (Sweden)

    V. Nicolin

    2010-05-01

    Full Text Available During the last decade, a more detailed knowledge of molecular mechanisms involved in osteoclastogenesis has driven research efforts in the development and screening of compound libraries of several small molecules that specifically inhibit the pathway involved in the commitment of the osteoclast precursor cells. Natural compounds that suppress osteoclast differentiation may have therapeutic value in treating osteoporosis and other bone erosive diseases such as rheumatoid arthritis or metastasis associated with bone loss. In ongoing investigation into anti-osteoporotic compounds from natural products we have analyzed the effect of Tanshinone VI on osteoclasts differentiation, using a physiologic three-dimensional osteoblast/bone marrow model of cell co-culture. Tanshinone VI is an abietane diterpene extracted from the root of Salvia miltiorrhiza Bunge (Labiatae, a Chinese traditional crude drug, ‘’Tan-Shen’’. Tashinone has been widely used in clinical practice for the prevention of cardiac diseases, arthritis and other inflammation-related disorders based on its pharmacological actions in multiple tissues. Although Tanshinone VI A has been used as a medicinal agent in the treatment of many diseases, its role in osteoclast-related bone diseases remains unknown. We showed previously that Tanshinone VI greatly inhibits osteoclast differentiation and suppresses bone resorption through disruption of the actin ring; subsequently, we intended to examine the precise inhibitory mechanism of Tanshinone VI on osteoclast differentiating factor. This study shows, for the first time, that Tanshinone VI prevents osteoclast differentiation by inhibiting RANKL expression and NFkB induction.

  16. Prevention of bone resorption by intake of phytoestrogens in postmenopausal women: a meta-analysis.

    Science.gov (United States)

    Salari Sharif, Pooneh; Nikfar, Shekoufeh; Abdollahi, Mohammad

    2011-09-01

    Phytoestrogens as selective estrogen receptor modulators like compounds may consider as a therapeutic option in osteoporosis. In this regard, the effect of phytoestrogens on bone biomarkers was examined in several trials which their results are controversial. We aimed this meta-analysis to evaluate the net effect of phytoestrogens on bone markers. A thorough search was conducted from 2000 to 2010 in English articles. All randomized clinical trials were reviewed, and finally, 11 eligible randomized clinical trials were selected for meta-analysis. Totally 1,252 postmenopausal women were enrolled in the study by considering the changes of pyridinoline (Pyd), desoxypyridinoline (Dpyd), bone alkaline phosphatase, and osteocalcin concentrations in urine and serum after phytoestrogens consumption. The urine Pyd and Dpyd levels decreased significantly in phytoestrogens consumers. Effect size and effect size for weighted mean difference of urine Pyd levels showed -1.229171 (95% confidence interval (CI) = -1.927639 to -0.530703) and -9.780623 (95% CI = -14.240401 to -5.320845), respectively, a significant results in comparison to control group and significant results for Dpyd -0.520132 (95% CI = -0.871988 to -0.168275) and -0.818582 (95% CI = -1.247758 to -0.389407), respectively. Meta-analysis indicates that phytoestrogens intake can prevent bone resorption, but its benefits on bone formation are not significant. This favorable effect was observed in low doses and in at least 3 weeks of phytoestrogens intake.

  17. High Protein Intake Improves Insulin Sensitivity but Exacerbates Bone Resorption in Immobility (WISE Study)

    Science.gov (United States)

    Heer, Martina; Smith, Scott M.; Frings-Meuthen, Petra; Zwart, Sara R.; Baecker, Natalie

    2012-01-01

    Inactivity, like bed rest (BR), causes insulin resistance (IR) and bone loss even in healthy subjects. High protein intake seems to mitigate this IR but might exacerbate bone loss. We hypothesized that high protein intake (animal:vegetable protein ratio: 60:40), isocaloric, compared to the control group plus high potassium intake would prevent IR without affecting bone turnover. After a 20-day ambulatory adaptation to controlled confinement and diet, 16 women participated in a 60-day, 6 deg head-down-tilt BR and were assigned randomly to one of the two groups. Control subjects (CON, n=8) received 1g/kg body mass/d dietary protein. Nutrition subjects (NUT, n=8) received 1.45g/kg body mass/d dietary protein plus 7.2g branched chain amino acids per day during BR. All subjects received 1670 kcal/d. Bed rest decreased glucose disposal by 35% (pprotein intake prevented insulin resistance, but exacerbated bed rest induced increase in bone resorption markers C-telopeptide (> 30%) and Ntelopeptide (>20%) (both: pprotein intake. We conclude from these results that high protein intake might positively affect glucose tolerance, but might also foster bone loss. Further long-duration studies are mandatory before high protein intake for diabetic patients, who have an increased fracture risk, might be recommended.

  18. The Experimental Study on the Effect Calcitonin Gene-related Peptide on Bone Resorption Mediated by Interleukin-1

    Institute of Scientific and Technical Information of China (English)

    LIAN; Kai(

    2001-01-01

    [1]Suda T Udagawa I Nakamura T et al.Modulation of osteoclast? Differentiation by local factors.Bone 1995 17(suppl 2) :875[2]Kanehisa J Heersche J N M.Osteoclastic bone resorption:in vitro analysis of the rate of resorption and migration of individual osteoclasts.Bone 1988 9:73[3]高建军.破骨细胞成熟和活化以及骨吸收机制.内分泌学分册 1998 18(2):57[4]Cohen-Solal M E Granlet A M Denne M A et al.Peripheral blood monocyte culture supernatants of menopausel women can induce bone resorption:involvement of cytokines.J Clin Endocrinol Metab 1993 77:1648[5]Kimble R B Vannice J L Bloedow D C et al.Interleukin-1 receptor antagonist decreases bone loss and bone resorption in ovariectomized rats.J Clin Invest 1994 93:1959[6]Horowitz M C.Cytokines and estrogen in bone:Antiosteoporotic ettects.Science 1993 260:626[7]Thomson B M Saklatvala J Chambers T J et al.Osteoblasts mediate interleukin 1 stimulation of bone resorption by rat osteoclasts.J Exp Med 1986 164:104[8]Goltzman D Mitchell J.Interaction of calciton and CGRP at receptor sites in target tissue.Science 1985 227:1343[9]Millet I Vignery A.The neuropeptide CGRP inhibits TNF-α but poorly induces IL-6 production by fetal rat osteoblasts.Cytokine 1997 12(9):999[10]Taichman R S Hauschka P V.Effects of IL-1βand TNF-α on osteoblastic expression of osteocalcin and mineralized extracellular matrix in vitro.Inflammation.1992 16:587

  19. Transient bone resorption following finger replantation: a report of 3 cases

    Directory of Open Access Journals (Sweden)

    Lucchina Stefano

    2011-06-01

    Full Text Available 【Abstract】Radiographic changes consisting of al- terations in mineral content, osteopaenia or destructive neu- ropathy that occur following successful finger replantation have already been described. We report our experience about four fingers in three individuals in whom bone changes de- veloped in the first three months postoperatively with com- plete “restitution ad integrum”. Three patients, 21-49 years old (average 36 years sus- tained a clean-cut amputation of four fingers. The first pa- tient had an amputation at the base of the middle phalanx of the index finger and the second patient at the base of the proximal phalanx of the ring finger. The third had an ampu- tation at the base of the first metacarpal bone and the proxi- mal phalanx of the small finger in a five finger amputation. In the first case, two dorsal veins and two palmar digital arter- ies and nerves were repaired. In the second case, one pal- mar artery and one dorsal vein were reanastomosed. In the third case at the thumb, two dorsal veins and two palmar digital arteries and nerves were reconstructed. At the small finger, one dorsal vein, one palmar digital artery and two digital nerves were reconstructed. Bone fixation was achieved with two and three K-wires or tension-band wiring. Replantation was successful in all cases. Three weeks after replantation, the X-rays showed rapid development of osteopaenia in the juxtaarticular region and metaphyses of the bone. These changes were followed by subperiosteal, intracortical and endosteal bone resorption. No further sur- gical procedures or splintage were needed and hand therapy was not discontinued. At 10-13 weeks (average 12 weeks postoperatively, the X-rays showed a complete recovery with new periosteal bone formation. We suggest that the radiographic changes after finger replantation are transient, first evident subperiosteally and progressing centrally. They may reflect small-vessel com- promise and microinfarction

  20. Three-dimensional analysis of alveolar bone resorption by image processing of 3-D dental CT images

    Science.gov (United States)

    Nagao, Jiro; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Yamada, Shohzoh; Naitoh, Munetaka

    2006-03-01

    We have developed a novel system that provides total support for assessment of alveolar bone resorption, caused by periodontitis, based on three-dimensional (3-D) dental CT images. In spite of the difficulty in perceiving the complex 3-D shape of resorption, dentists assessing resorption location and severity have been relying on two-dimensional radiography and probing, which merely provides one-dimensional information (depth) about resorption shape. However, there has been little work on assisting assessment of the disease by 3-D image processing and visualization techniques. This work provides quantitative evaluation results and figures for our system that measures the three-dimensional shape and spread of resorption. It has the following functions: (1) measures the depth of resorption by virtually simulating probing in the 3-D CT images, taking advantage of image processing of not suffering obstruction by teeth on the inter-proximal sides and much smaller measurement intervals than the conventional examination; (2) visualizes the disposition of the depth by movies and graphs; (3) produces a quantitative index and intuitive visual representation of the spread of resorption in the inter-radicular region in terms of area; and (4) calculates the volume of resorption as another severity index in the inter-radicular region and the region outside it. Experimental results in two cases of 3-D dental CT images and a comparison of the results with the clinical examination results and experts' measurements of the corresponding patients confirmed that the proposed system gives satisfying results, including 0.1 to 0.6mm of resorption measurement (probing) error and fairly intuitive presentation of measurement and calculation results.

  1. Muramyl Dipeptide Enhances Lipopolysaccharide-Induced Osteoclast Formation and Bone Resorption through Increased RANKL Expression in Stromal Cells

    Directory of Open Access Journals (Sweden)

    Masahiko Ishida

    2015-01-01

    Full Text Available Lipopolysaccharide (LPS is bacterial cell wall component capable of inducing osteoclast formation and pathological bone resorption. Muramyl dipeptide (MDP, the minimal essential structural unit responsible for the immunological activity of peptidoglycans, is ubiquitously expressed by bacterium. In this study, we investigated the effect of MDP in LPS-induced osteoclast formation and bone resorption. LPS was administered with or without MDP into the supracalvariae of mice. The number of osteoclasts, the level of mRNA for cathepsin K and tartrate-resistant acid phosphatase (TRAP, the ratio of the bone destruction area, the level of tartrate-resistant acid phosphatase form 5b (TRACP 5b, and C-terminal telopeptides fragments of type I collagen as a marker of bone resorption in mice administrated both LPS and MDP were higher than those in mice administrated LPS or MDP alone. On the other hand, MDP had no effect on osteoclastogenesis in parathyroid hormone administrated mice. MDP enhanced LPS-induced receptor activator of NF-κB ligand (RANKL expression and Toll-like receptor 4 (TLR4 expression in vivo and in stromal cells in vitro. MDP also enhanced LPS-induced mitogen-activated protein kinase (MAPK signaling, including ERK, p38, and JNK, in stromal cells. These results suggest that MDP might play an important role in pathological bone resorption in bacterial infection diseases.

  2. Hyptis pectinata gel prevents alveolar bone resorption in experimental periodontitis in rats

    Directory of Open Access Journals (Sweden)

    Mônica S. Paixão

    2015-02-01

    Full Text Available Hyptis pectinata (L. Poit., Lamiaceae, is an aromatic, abundant and broadly used plant species in Sergipe to treat oral and gastrointestinal pain and inflammation. The aim of the present study was to analyze the relation between periodontitis and changes in the corporal mass and alveolar bone structure after induction of experimental periodontal disease in rat treated or not treated with H. pectinata gel at 5% (GS5% and 10% (GS10%, comparing their effects with doxycycline gel at 10% (D10%, positive control, vehicle gel (negative control and a group with experimental periodontal disease, but non-treated. The gels were locally applied in the gingival region immediately after the experimental periodontal disease induction by ligature (3×/day, 11 days. Bone destruction was determined through clinical exam, histopathological analysis and cone beam computed tomography of the experimental animals (n = 36. After 11 days of periodontitis induction, all groups that received ligature presented a decrease in the corporal mass, except to the naïve group (without experimental periodontal disease (p < 0.05. Computed tomography results have shown healthy bone structure in the group I and bone resorption for the test groups. Histopathological analysis confirmed the healthy bone structure for naïve group animals, while the test groups exhibited bone loss in several degrees. In particular, the non-treated group animals had an intense inflammatory process. When the periodontium of the animals treated with GS10% was histopathologically analyzed, insertion periodontium was preserved. The results for these groups were significantly different of the vehicle group (p < 0.05. According to the results, the gel based in the aqueous extract of H. pectinata at 10% can prevent bone loss in experimental periodontal disease similarly to doxycycline 10%.

  3. Resorption of monetite granules in alveolar bone defects in human patients.

    Science.gov (United States)

    Tamimi, Faleh; Torres, Jesus; Bassett, David; Barralet, Jake; Cabarcos, Enrique L

    2010-04-01

    Bone grafting is often required to restore mandibular or maxillary bone volume prior to prosthetic tooth root implantation. Preclinical animal models are often used to study the in vivo properties of new bone graft products designed for human use. Although animal studies may offer valuable data regarding bioperformance, materials do not necessarily perform the same in human patients. In this study we implanted bovine hydroxyapatite (BH), a widely used porous apatite granule, and dicalcium phosphate anhydrous (monetite) granules, bilaterally in human patients post extraction alveolar sockets. After six months, histomorphometrical analysis of the biopsies revealed that the amount of bone regenerated with monetite (59.5 +/- 13%) was significantly higher than that obtained with BH (33.1% +/- 4.9), while the amount of unresorbed graft was higher in the sockets treated with BH (37.8 +/- 6.1) than in those implanted with monetite (25.8 +/- 14.3). Resorption of calcium phosphate ceramics is discussed by applying the Hixon-Crowell dissolution model.

  4. Transient bone resorption following finger replantation: a report of 3 cases

    Institute of Scientific and Technical Information of China (English)

    Stefano Lucchina; Hillary A. Becker; Cesare Fusetti; Alexander Y. Shin

    2011-01-01

    Radiographic changes consisting of alterations in mineral content, osteopaenia or destructive neuropathy that occur following successful finger replantation have already been described. We report our experience about four fingers in three individuals in whom bone changes developed in the first three months postoperatively with complete "restitution ad integrum".Three patients, 21-49 years old (average 36 years) sustained a clean-cut amputation of four fingers. The first patient had an amputation at the base of the middle phalanx of the index finger and the second patient at the base of the proximal phalanx of the ring finger. The third had an amputation at the base of the first metacarpal bone and the proximal phalanx of the small finger in a five finger amputation. In the first case, two dorsal veins and two palmar digital arteries and nerves were repaired. In the second case, one palmar artery and one dorsal vein were reanastomosed. In the third case at the thumb, two dorsal veins and two palmar digital arteries and nerves were reconstructed. At the small finger, one dorsal vein, one palmar digital artery and two digital nerves were reconstructed. Bone fixation was achieved with two and three K-wires or tension-band wiring. Replantation was successful in all cases. Three weeks after replantation, the X-rays showed rapid development of osteopaenia in the juxtaartieular region and metaphyses of the bone. These changes were followed by subperiosteal,intracortical and endosteal bone resorption. No further surgical procedures or splintage were needed and hand therapy was not discontinued. At 10-13 weeks (average 12 weeks)postoperatively, the X-rays showed a complete recovery with new periosteal bone formation.We suggest that the radiographic changes after finger replantation are transient, first evident subperiosteally and progressing centrally. They may reflect small-vessel compromise and microinfarction and transient hyperemia secondary to neurovascular damage or to

  5. Calcium-41 as a long-term biological tracer for bone resorption

    Science.gov (United States)

    Elmore, David; Bhattacharyya, Maryka H.; Sacco-Gibson, Nancy; Peterson, David P.

    1990-12-01

    The use of 41Ca (half-life 1 × 10 5 yr) as a tracer for studying calcium metabolism in living systems is compared to the shorter-lived radionuclides 45Ca (165 d) and 47Ca (45 d) and the stable isotopes 42Ca and 44Ca. The feasibility of using accelerator mass spectrometry (AMS) measurements of 41Ca for studying multi-year calcium resorption in humans was tested as part of a companion study that used 45Ca to measure the effects of dietary cadmium on calcium metabolism in dogs. It was shown that Ca resorbed from prelabeled bones correlates well with 45Ca for a period of 28 weeks. The advantage of 41Ca is that, even with a negligible radiation dose, it can be measured by AMS long after the 45Ca becomes unmeasurable.

  6. Azanitrile Cathepsin K Inhibitors: Effects on Cell Toxicity, Osteoblast-Induced Mineralization and Osteoclast-Mediated Bone Resorption.

    Directory of Open Access Journals (Sweden)

    Zhong-Yuan Ren

    Full Text Available The cysteine protease cathepsin K (CatK, abundantly expressed in osteoclasts, is responsible for the degradation of bone matrix proteins, including collagen type 1. Thus, CatK is an attractive target for new anti-resorptive osteoporosis therapies, but the wider effects of CatK inhibitors on bone cells also need to be evaluated to assess their effects on bone. Therefore, we selected, among a series of synthetized isothiosemicarbazides, two molecules which are highly selective CatK inhibitors (CKIs to test their effects on osteoblasts and osteoclasts.Cell viability upon treatment of CKIs were was assayed on human osteoblast-like Saos-2, mouse monocyte cell line RAW 264.7 and mature mouse osteoclasts differentiated from bone marrow. Osteoblast-induced mineralization in Saos-2 cells and in mouse primary osteoblasts from calvaria, with or without CKIs,; were was monitored by Alizarin Red staining and alkaline phosphatase activity, while osteoclast-induced bone resorption was performed on bovine slices.Treatments with two CKIs, CKI-8 and CKI-13 in human osteoblast-like Saos-2, murine RAW 264.7 macrophages stimulated with RANKL and mouse osteoclasts differentiated from bone marrow stimulated with RANKL and MCSF were found not to be toxic at doses of up to 100 nM. As probed by Alizarin Red staining, CKI-8 did not inhibit osteoblast-induced mineralization in mouse primary osteoblasts as well as in osteoblast-like Saos-2 cells. However, CKI-13 led to a reduction in mineralization of around 40% at 10-100 nM concentrations in osteoblast-like Saos-2 cells while it did not in primary cells. After a 48-hour incubation, both CKI-8 and CKI-13 decreased bone resorption on bovine bone slices. CKI-13 was more efficient than the commercial inhibitor E-64 in inhibiting bone resorption induced by osteoclasts on bovine bone slices. Both CKI-8 and CKI-13 created smaller bone resorption pits on bovine bone slices, suggesting that the mobility of osteoclasts was slowed

  7. Fisetin antagonizes cell fusion, cytoskeletal organization and bone resorption in RANKL-differentiated murine macrophages.

    Science.gov (United States)

    Kim, Yun-Ho; Kim, Jung-Lye; Lee, Eun-Jung; Park, Sin-Hye; Han, Seon-Young; Kang, Soon Ah; Kang, Young-Hee

    2014-03-01

    Osteoclastogenesis is comprised of several stage s including progenitor survival, differentiation to mononuclear preosteoclasts, cell fusion to multinuclear mature osteoclasts, and activation to osteoclasts with bone resorbing activity. Botanical antioxidants are now being increasingly investigated for their health-promoting effects on bone. This study investigated that fisetin, a flavonol found naturally in many fruits and vegetables, suppressed osteoclastogenesis by disturbing receptor activator of nuclear factor (NF)-κB ligand (RANKL)-mediated signaling pathway and demoting osteoclastogenic protein induction. Nontoxic fisetin at ≤10 μM inhibited the induction of RANK, tumor necrosis factor receptor associated factor 6 (TRAF6) and the activation of NF-κB in RANKL-stimulated RAW 264.7 macrophages. In RANKL-differentiated osteoclasts cell fusion protein of E-cadherin was induced, which was dampened by fisetin. The formation of tartrate-resistance acid phosphatase-positive multinucleated osteoclasts was suppressed by adding fisetin to RANKL-exposed macrophages. It was also found that fisetin reduced actin ring formation and gelsolin induction of osteclasts enhanced by RANKL through disturbing c-Src-proline-rich tyrosine kinase 2 signaling. Fisetin deterred preosteoclasts from the cell-cell fusion and the organization of the cytoskeleton to seal the resorbing area and to secret protons for bone resorption. Consistently, the 5 day-treatment of fisetin diminished RANKL-induced cellular expression of carbonic anhydrase II and integrin β3 concurrently with a reduction of osteoclast bone-resorbing activity. Therefore, fisetin was a natural therapeutic agent retarding osteoclast fusion and cytoskeletal organization such as actin rings and ruffled boarder, which is a property of mature osteoclasts and is required for osteoclasts to resorb bone.

  8. 雷耐酸锶在骨吸收中的作用%Effect of strontium ranelate on bone resorption

    Institute of Scientific and Technical Information of China (English)

    万英明; 王景云; 王为民; 李婉

    2008-01-01

    BACKGROUND: Most of anti-osteoporosis drugs can only inhibit bone resorption, but can not improve the bone formation. So far, Strontium ranelate is the only anti-osteoporosis drug that has a dual effect on bone resorption and bone formation. Through the retrieval of related studies, the present review article evaluates the current understanding of strontium ranelate effects on bone resorption based on the pharmacologic experiments, clinical studies, action mechanisms. Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been widely used on clinic; however, there are still few reports addressing rhBMP-2-induced osteogenesis in intervertebral disc.%大多数抗骨质疏松药物只能抑制骨吸收而不能促进骨的形成.雷奈酸锶是目前为止唯一具有"双重作用"的抗骨质疏松药物,既能抑制骨的吸收又能促进骨的形成.通过检索文献,文章从药理实验、临床研究及作用机制3方面总结骨吸收中雷奈酸锶的作用和研究进展.

  9. Does collagen trigger the recruitment of osteoblasts into vacated bone resorption lacunae during bone remodeling?

    DEFF Research Database (Denmark)

    Abdelgawad, Mohamed Essameldin; Søe, Kent; Andersen, Thomas Levin;

    2014-01-01

    Osteoblast recruitment during bone remodeling is obligatory to re-construct the bone resorbed by the osteoclast. This recruitment is believed to be triggered by osteoclast products and is therefore likely to start early during the remodeling cycle. Several osteoclast products with osteoblast recr...

  10. Preliminary evidence of early bone resorption in a sheep model of acute burn injury: an observational study.

    Science.gov (United States)

    Klein, Gordon L; Xie, Yixia; Qin, Yi-Xian; Lin, Liangjun; Hu, Minyi; Enkhbaatar, Perenlei; Bonewald, Lynda F

    2014-03-01

    Treatment with bisphosphonates within the first 10 days of severe burn injury completely prevents bone loss. We therefore postulated that bone resorption occurs early post burn and is the primary explanation for acute bone loss in these patients. Our objective was to assess bone for histological and biomechanical evidence of early resorption post burn. We designed a randomized controlled study utilizing a sheep model of burn injury. Three sheep received a 40 % total body surface area burn under isoflurane anesthesia, and three other sheep received cotton-smoke inhalation and served as control. Burned sheep were killed 5 days post procedure and controls were killed 2 days post procedure. Backscatter scanning electron microscopy was performed on iliac crests obtained immediately postmortem along with quantitative histomorphometry and compression testing to determine bone strength (Young's modulus). Blood ionized Ca was also determined in the first 24 h post procedure as was urinary CTx. Three of three sheep killed at 5 days had evidence of scalloping of the bone surface, an effect of bone resorption, whereas none of the three sheep killed at 2 days post procedure had scalloping. One of the three burned sheep killed at 5 days showed quantitative doubling of the eroded surface and halving of the bone volume compared to sham controls. Mean values of Young's modulus were approximately one third lower in the burned sheep killed at 5 days compared to controls, p = 0.08 by unpaired t test, suggesting weaker bone. These data suggest early post-burn bone resorption. Urine CTx normalized to creatinine did not differ between groups at 24 h post procedure because the large amounts of fluids received by the burned sheep may have diluted urine creatinine and CTx and because the urine volume produced by the burned sheep was threefold that of the controls. We calculated 24 h urinary CTx excretion, and with this calculation CTx excretion/24 h in the burned sheep was

  11. Low dose pioglitazone does not affect bone formation and resorption markers or bone mineral density in streptozocin-induced diabetic rats.

    Science.gov (United States)

    Tsirella, E; Mavrakanas, T; Rager, O; Tsartsalis, S; Kallaras, K; Kokkas, B; Mironidou-Tzouveleki, M

    2012-04-01

    Our study aims to investigate the effect of a low-dose pioglitazone regimen on bone mineral density and bone formation-resorption markers in control and diabetic rats. Wistar rats were divided into 4 groups: non-diabetic controls, control rats receiving pioglitazone (3 mg/kg), streptozocin-treated diabetic rats (50 mg/kg), diabetic rats treated with pioglitazone (3 mg/kg). The duration of the experiment was 8 weeks. Diabetes in our rats was associated with weight loss, increased urinary calcium excretion and reduced plasma osteocalcin levels. Diabetes mellitus did not affect bone mineral density. Pioglitazone administration had no impact on bone formation and resorption markers levels and did not modify bone mineral density in the four studied groups. Pioglitazone at the 3 mg/kg dose was not associated with significant skeletal complications in our experimental model.

  12. Congenital adrenal hyperplasia: a case report with premature teeth exfoliation and bone resorption.

    Science.gov (United States)

    Angelopoulou, Matina V; Kontogiorgos, Elias; Emmanouil, Dimitris

    2015-06-01

    Congenital adrenal hyperplasia (CAH) is an inherited autosomal recessive disorder characterized by insufficient production of cortisol. The aim of this case report was to present a child with CAH, premature exfoliation of primary teeth and accelerated eruption of his permanent teeth related to bone resorption. A 4.5-year-old Caucasian boy with CAH and long-term administration of glucocorticoids was referred for dental restoration. Clinical examination revealed primary molars with worn stainless steel crowns, severe attrition of the upper canines, and absence of the upper incisors. Before the completion of treatment, abnormal mobility of the first upper primary molars and the lower incisors was detected, and a few days later the teeth exfoliated prematurely. Histologic examination revealed normal tooth structure. Alkaline phosphatase and blood cells values were normal. Eruption of the permanent dentition was also accelerated. Tooth mobility was noticed in the permanent teeth as soon as they erupted, along with bone destruction. Examination revealed an elevated level of receptor activator of nuclear factor-κB ligand and lower-than-normal osteoprotegerin and vitamin D levels. The patient was treated with vitamin D supplements, and his teeth have been stable ever since. CAH is a serious chronic disorder appearing in children with accelerated dental development and possibly premature loss of primary teeth.

  13. Biomechanical Loading Modulates Proinflammatory and Bone Resorptive Mediators in Bacterial-Stimulated PDL Cells

    Directory of Open Access Journals (Sweden)

    Andressa Vilas Boas Nogueira

    2014-01-01

    Full Text Available The present study aimed to evaluate in vitro whether biomechanical loading modulates proinflammatory and bone remodeling mediators production by periodontal ligament (PDL cells in the presence of bacterial challenge. Cells were seeded on BioFlex culture plates and exposed to Fusobacterium nucleatum ATCC 25586 and/or cyclic tensile strain (CTS of low (CTSL and high (CTSH magnitudes for 1 and 3 days. Synthesis of cyclooxygenase-2 (COX2 and prostaglandin E2 (PGE2 was evaluated by ELISA. Gene expression and protein secretion of osteoprotegerin (OPG and receptor activator of nuclear factor kappa-B ligand (RANKL were evaluated by quantitative RT-PCR and ELISA, respectively. F. nucleatum increased the production of COX2 and PGE2, which was further increased by CTS. F. nucleatum-induced increase of PGE2 synthesis was significantly (P<0.05 increased when CTSH was applied at 1 and 3 days. In addition, CTSH inhibited the F. nucleatum-induced upregulation of OPG at 1 and 3 days, thereby increasing the RANKL/OPG ratio. OPG and RANKL mRNA results correlated with the protein results. In summary, our findings provide original evidence that CTS can enhance bacterial-induced syntheses of molecules associated with inflammation and bone resorption by PDL cells. Therefore, biomechanical, such as orthodontic or occlusal, loading may enhance the bacterial-induced inflammation and destruction in periodontitis.

  14. Early Effects of Single and Low-Frequency Repeated Administration of Teriparatide, hPTH(1-34), on Bone Formation and Resorption in Ovariectomized Rats.

    Science.gov (United States)

    Isogai, Yukihiro; Takao-Kawabata, Ryoko; Takakura, Aya; Sugimoto, Emika; Nakazono, Osamu; Ikegaki, Ichiro; Kuriyama, Hiroshi; Ishizuya, Toshinori

    2015-10-01

    Intermittent repeated administration of teriparatide (TPTD) has potent anabolic effects on bones in vivo. However, TPTD has both anabolic and catabolic effects on osteoblasts in vitro, and the mechanisms underlying its promotion of bone formation are unclear. This study aimed to elucidate the time-dependent changes in bone formation and resorption by examining changes in bone turnover markers and bone tissue over time after TPTD administration with low frequency in ovariectomized rats. The amount of serum osteocalcin, a bone formation marker, was transiently reduced after single TPTD administration, but increased thereafter, remaining increased for several days. In contrast, the amount of excreted urinary C-telopeptide, a bone resorption marker, increased transiently after single TPTD administration, and subsequently returned to control levels on the day after administration. Tissue histomorphometric analyses conducted 8 h after administration showed no changes in bone formation or bone resorption parameters. However, at 48 h, the bone formation parameters OS/BS and Ob.S/BS were increased, while the bone resorption parameter ES/BS was decreased. After repeated TPTD administration for 4 weeks, OS/BS, Ob.S/BS, and MS/BS increased, while Oc.S/BS decreased. Serum osteocalcin at 4 weeks after repeated administration was significantly correlated with OS/BS and Ob.S/BS. These present findings indicate that TPTD has dual, time-dependent effects on bone resorption and bone formation. Immediately after single administration, there was transient promotion of bone resorption and suppression of bone formation. However, sustained stimulation of bone formation occurred thereafter. Furthermore, these data suggest that this sustained bone formation led to anabolic effects with repeated TPTD administration.

  15. Inhibitory effects of French pine bark extract, Pycnogenol®, on alveolar bone resorption and on the osteoclast differentiation.

    Science.gov (United States)

    Sugimoto, Hideki; Watanabe, Kiyoko; Toyama, Toshizo; Takahashi, Shun-suke; Sugiyama, Shuta; Lee, Masaichi-Chang-il; Hamada, Nobushiro

    2015-02-01

    Pycnogenol(®) (PYC) is a standardized bark extract from French maritime pine (Pinus pinaster Aiton). We examined the inhibitory effects of PYC on alveolar bone resorption, which is a characteristic feature of periodontitis, induced by Porphyromonas gingivalis (P. gingivalis) and osteoclast differentiation. In rat periodontitis model, rats were divided into four groups: group A served as the non-infected control, group B was infected orally with P. gingivalis ATCC 33277, group C was administered PYC in the diet (0.025%: w/w), and group D was infected with P. gingivalis and administered PYC. Administration of PYC along with P. gingivalis infection significantly reduced alveolar bone resorption. Treatment of P. gingivalis with 1 µg/ml PYC reduced the number of viable bacterial cells. Addition of PYC to epithelial cells inhibited adhesion and invasion by P. gingivalis. The effect of PYC on osteoclast formation was confirmed by tartrate-resistant acid phosphatase staining. PYC treatment significantly inhibited osteoclast formation. Addition of PYC (1-100 µg/ml) to purified osteoclasts culture induced cell apoptosis. These results suggest that PYC may prevent alveolar bone resorption through its antibacterial activity against P. gingivalis and by suppressing osteoclastogenesis. Therefore, PYC may be useful as a therapeutic and preventative agent for bone diseases such as periodontitis.

  16. Osteogenic protein 1 device increases bone formation and bone graft resorption around cementless implants

    DEFF Research Database (Denmark)

    Jensen, Thomas B; Overgaard, Søren; Lind, Martin;

    2002-01-01

    In each femoral condyle of 8 Labrador dogs, a non weight-bearing hydroxyapatite-coated implant was inserted surrounded by a 3 mm gap. Each gap was filled with bone allograft or ProOsteon with or without OP-1 delivered in a bovine collagen type I carrier (OP-1 device). 300 microg OP-1 was used in ...

  17. PPARG Post-translational Modifications Regulate Bone Formation and Bone Resorption

    Directory of Open Access Journals (Sweden)

    L.A. Stechschulte

    2016-08-01

    Full Text Available The peroxisome proliferator-activated receptor gamma (PPARγ regulates osteoblast and osteoclast differentiation, and is the molecular target of thiazolidinediones (TZDs, insulin sensitizers that enhance glucose utilization and adipocyte differentiation. However, clinical use of TZDs has been limited by side effects including a higher risk of fractures and bone loss. Here we demonstrate that the same post-translational modifications at S112 and S273, which influence PPARγ pro-adipocytic and insulin sensitizing activities, also determine PPARγ osteoblastic (pS112 and osteoclastic (pS273 activities. Treatment of either hyperglycemic or normoglycemic animals with SR10171, an inverse agonist that blocks pS273 but not pS112, increased trabecular and cortical bone while normalizing metabolic parameters. Additionally, SR10171 treatment modulated osteocyte, osteoblast, and osteoclast activities, and decreased marrow adiposity. These data demonstrate that regulation of bone mass and energy metabolism shares similar mechanisms suggesting that one pharmacologic agent could be developed to treat both diabetes and metabolic bone disease.

  18. Silicon supplementation improves the bone mineral density of calcium-deficient ovariectomized rats by reducing bone resorption.

    Science.gov (United States)

    Kim, Mi-Hyun; Bae, Yun-Jung; Choi, Mi-Kyeong; Chung, Yoon-Sok

    2009-06-01

    The purpose of this study was to investigate the effect of silicon (Si) supplementation on bone mineral density (BMD) and bone metabolism parameters relative to calcium (Ca) intake levels in ovariectomized rats. A total of 72 female Wistar rats (6 weeks) were ovariectomized (OVX) and divided into six groups, and Si (500 mg of Si per kilogram of feed) was or was not administered with diets containing various levels of Ca (0.1%, 0.5%, and 1.5%) for 10 weeks. The groups were as follows: (1) Ca-deficient group (0.1% Ca), (2) Ca-deficient with Si supplementation group, (3) adequate Ca group (0.5% Ca), (4) adequate Ca with Si supplementation group, (5) high Ca group (1.5% Ca), and (6) high Ca with Si supplementation group. Si supplementation significantly increased the BMD of the femur and tibia in Ca-deficient OVX rats, while no change was observed with Si supplementation in the BMD of the spine, femur, and tibia in the adequate and high Ca groups. Serum alkaline phosphatase and osteocalcin levels were not affected by Si supplementation or Ca intake levels. C-telopeptide type I collagen levels were significantly decreased as a result of Si supplementation in Ca-deficient OVX rats. In summary, Si supplementation produced positive effects on bone mineral density in Ca-deficient OVX rats by reducing bone resorption. Therefore, Si supplementation may also prove to be helpful in preventing osteoporosis in postmenopausal women whose calcium intake is insufficient.

  19. Mouse tail vertebrae adapt to cyclic mechanical loading by increasing bone formation rate and decreasing bone resorption rate as shown by time-lapsed in vivo imaging of dynamic bone morphometry.

    Science.gov (United States)

    Lambers, Floor M; Schulte, Friederike A; Kuhn, Gisela; Webster, Duncan J; Müller, Ralph

    2011-12-01

    It is known that mechanical loading leads to an increase in bone mass through a positive shift in the balance between bone formation and bone resorption. How the remodeling sites change over time as an effect of loading remains, however, to be clarified. The purpose of this paper was to investigate how bone formation and resorption sites are modulated by mechanical loading over time by using a new imaging technique that extracts three dimensional formation and resorption parameters from time-lapsed in vivo micro-computed tomography images. To induce load adaptation, the sixth caudal vertebra of C57BL/6 mice was cyclically loaded through pins in the adjacent vertebrae at either 8 N or 0 N (control) three times a week for 5 min (3000 cycles) over a total of 4 weeks. The results showed that mechanical loading significantly increased trabecular bone volume fraction by 20% (pbone formation rate was on average 23% greater (pbone resorption rate was on average 25% smaller (pbone formation rate for the 8 N group was mostly an effect of a significantly increased surface of bone formation sites (on average 16%, pbone formation packages was less affected (on average 5% greater, pbone resorption sites was significantly reduced (on average 15%, pbone increased significantly by 24% (pbone decreased significantly by 24% (ptail vertebrae adapt to mechanical loading by increasing the surface of formation sites and decreasing the surface of resorption sites, leading to an overall increase in bone strength. This new imaging technique will provide opportunities to investigate in vivo bone remodeling in the context of disease and treatment options, with the added value that both bone formation and bone resorption parameters can be nondestructively calculated over time.

  20. Cortical bone resorption rate in elderly persons: Estimates from long-term in vivo measurements of 90Sr in the skeleton

    Energy Technology Data Exchange (ETDEWEB)

    Shagina, N. B.; Tolstykh, E. I.; Degteva, M. O.; Anspaugh, L. R.; Napier, Bruce A.

    2012-06-01

    The rate of cortical bone resorption was assessed from long-term in vivo measurements of 90Sr content in the skeleton for men aged 50-80 years and for women 0-30 years after menopause. Measurements of 90Sr were conducted with a whole body counter for residents of the Techa Riverside communities (Southern Urals, Russia), who ingested large amounts of 90Sr as a result of releases of liquid radioactive wastes into the river from the Mayak plutonium facility in early 1950s. The results of this study showed an increase in the rate of cortical bone resorption in both men and women, as based on the use of accidentally ingested 90Sr as a tracer for bone metabolism. In men there was a continuous gradual increase in the rate of cortical bone resorption after 55 years from 2.8 to 4.5%/year by the age of 75 years. In women, there was a doubled increase in the rate of cortical bone resorption after menopause of up to 6%/year; then the rate remained unchanged for 10-12 years with a subsequent gradual decline down to 5-5.5%/year. Comparison of the rate of cortical bone resorption in men and women older than 55 years showed that women expressed significantly higher levels of cortical bone resorption.

  1. Stimulation of a Gs-like G protein in the osteoclast inhibits bone resorption but enhances tartrate-resistant acid phosphatase secretion.

    Science.gov (United States)

    Moonga, B S; Pazianas, M; Alam, A S; Shankar, V S; Huang, C L; Zaidi, M

    1993-01-29

    Previous studies have demonstrated that G-protein agonists induce quiescence (Q effect) or retraction (R effect) in isolated osteoclasts. We now report the functional effects of such agonists on osteoclastic bone resorption and enzyme release. Exposure of osteoclasts to tetrafluoro-aluminate anions (AlF4-), a universal G protein stimulator, resulted in a marked concentration-dependent inhibition of bone resorption. This was associated with a dramatic increase in the secretion of the osteoclast-specific enzyme, tartrate-resistant acid phosphatase (TRAP). Cholera toxin, a Gs stimulator and a selective Q effect agonist, similarly abolished bone resorption and enhanced TRAP secretion. In contrast, pertussis toxin, a Gi inhibitor and a selective R effect agonist, inhibited bone resorption significantly, but slightly reduced enzyme release. The results suggest an involvement of a Gs-like G protein in TRAP secretion from the osteoclast, possibly through a cyclic AMP-dependent mechanism.

  2. Comparison of osteoclastogenesis and resorption activity of human osteoclasts on tissue culture polystyrene and on natural extracellular bone matrix in 2D and 3D.

    Science.gov (United States)

    Kleinhans, C; Schmid, F F; Schmid, F V; Kluger, P J

    2015-07-10

    Bone homeostasis is maintained by osteoblasts (bone formation) and osteoclasts (bone resorption). While there have been numerous studies investigating mesenchymal stem cells and their potential to differentiate into osteoblasts as well as their interaction with different bone substitute materials, there is only limited knowledge concerning in vitro generated osteoclasts. Due to the increasing development of degradable bone-grafting materials and the need of sophisticated in vitro test methods, it is essential to gain deeper insight into the process of osteoclastogenesis and the resorption functionality of human osteoclasts. Therefore, we focused on the comparison of osteoclastogenesis and resorption activity on tissue culture polystyrene (TCPS) and bovine extracellular bone matrices (BMs). Cortical bone slices were used as two-dimensional (2D) substrates, whereas a thermally treated cancellous bone matrix was used for three-dimensional (3D) experiments. We isolated primary human monocytes and induced osteoclastogenesis by medium supplementation. Subsequently, the expression of the vitronectin receptor (αVβ3) and cathepsin K as well as the characteristic actin formation on TCPS and the two BMs were examined. The cell area of human osteoclasts was analyzed on TCPS and on BMs, whereas significantly larger osteoclasts could be detected on BMs. Additionally, we compared the diameter of the sealing zones with the measured diameter of the resorption pits on the BMs and revealed similar diameters of the sealing zones and the resorption pits. We conclude that using TCPS as culture substrate does not affect the expression of osteoclast-specific markers. The analysis of resorption activity can successfully be conducted on cortical as well as on cancellous bone matrices. For new in vitro test systems concerning bone resorption, we suggest the establishment of a 2D assay for high throughput screening of new degradable bone substitute materials with osteoclasts.

  3. A delivery system specifically approaching bone resorption surfaces to facilitate therapeutic modulation of microRNAs in osteoclasts.

    Science.gov (United States)

    Liu, Jin; Dang, Lei; Li, Defang; Liang, Chao; He, Xiaojuan; Wu, Heng; Qian, Airong; Yang, Zhijun; Au, Doris W T; Chiang, Michael W L; Zhang, Bao-Ting; Han, Quanbin; Yue, Kevin K M; Zhang, Hongqi; Lv, Changwei; Pan, Xiaohua; Xu, Jiake; Bian, Zhaoxiang; Shang, Peng; Tan, Weihong; Liang, Zicai; Guo, Baosheng; Lu, Aiping; Zhang, Ge

    2015-06-01

    Dysregulated microRNAs in osteoclasts could cause many skeletal diseases. The therapeutic manipulation of these pathogenic microRNAs necessitates novel, efficient delivery systems to facilitate microRNAs modulators targeting osteoclasts with minimal off-target effects. Bone resorption surfaces characterized by highly crystallized hydroxyapatite are dominantly occupied by osteoclasts. Considering that the eight repeating sequences of aspartate (D-Asp8) could preferably bind to highly crystallized hydroxyapatite, we developed a targeting system by conjugating D-Asp8 peptide with liposome for delivering microRNA modulators specifically to bone resorption surfaces and subsequently encapsulated antagomir-148a (a microRNA modulator suppressing the osteoclastogenic miR-148a), i.e. (D-Asp8)-liposome-antagomir-148a. Our results demonstrated that D-Asp8 could facilitate the enrichment of antagomir-148a and the subsequent down-regulation of miR-148a in osteoclasts in vivo, resulting in reduced bone resorption and attenuated deterioration of trabecular architecture in osteoporotic mice. Mechanistically, the osteoclast-targeted delivery depended on the interaction between bone resorption surfaces and D-Asp8. No detectable liver and kidney toxicity was found in mice after single/multiple dose(s) treatment of (D-Asp8)-liposome-antagomir-148a. These results indicated that (D-Asp8)-liposome as a promising osteoclast-targeting delivery system could facilitate clinical translation of microRNA modulators in treating those osteoclast-dysfunction-induced skeletal diseases.

  4. Serotonin Is Involved in Autoimmune Arthritis through Th17 Immunity and Bone Resorption.

    Science.gov (United States)

    Chabbi-Achengli, Yasmine; Coman, Tereza; Collet, Corinne; Callebert, Jacques; Corcelli, Michelangelo; Lin, Hilène; Rignault, Rachel; Dy, Michel; de Vernejoul, Marie-Christine; Côté, Francine

    2016-04-01

    Rheumatoid arthritis is a chronic disease that results in a disabling and painful condition as it progresses to destruction of the articular cartilage and ankylosis of the joints. Although the cause of the disease is still unknown, evidence argues that autoimmunity plays an important part. There are increasing but contradictory views regarding serotonin being associated with activation of immunoinflammatory pathways and the onset of autoimmune reactions. We studied serotonin's involvement during collagen-induced arthritis in wild-type and Tph1(-/-) mice, which have markedly reduced peripheral serotonin levels. In wild-type mice, induction of arthritis triggered a robust increase in serotonin content in the paws combined with less inflammation. In Tph1(-/-) mice with arthritis, a marked increase in the clinical and pathologic arthritis scores was noticed. Specifically, in Tph1(-/-) mice with arthritis, a significant increase in osteoclast differentiation and bone resorption was observed with an increase in IL-17 levels in the paws and in Th17 lymphocytes in the draining lymph nodes, whereas T-regulatory cells were dampened. Ex vivo serotonin and agonists of the 5-HT2A and 5-HT2B receptors restored IL-17 secretion from splenocytes and Th17 cell differentiation in Tph1(-/-) mice. These findings indicate that serotonin plays a fundamental role in arthritis through the regulation of the Th17/T-regulatory cell balance and osteoclastogenesis.

  5. A digital subtraction radiography based tool for periodontal bone resorption analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schiabel, Homero; Rodrigues, Eveline B., E-mail: homero@sc.usp.br [University of Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). Dept. of Electrical Engineering; Rubira-Bullen, Izabel R.F. [University of Sao Paulo (USP), Bauru, SP (Brazil). Bauru Dentistry School

    2011-07-01

    The aim of this paper was to describe an aided diagnosis scheme for periodontal bone resorption so that the dentist can make an early diagnosis of the periodontal disease and establish the best treatment plan to increase the success of healing. Three ways of displaying the results are provided: qualitative, simple quantitative and colored-percentage quantitative views. A total of 72 pairs of in vitro radiographic images were used. The main procedure registers the images perspective projection aimed to align them in rotation and translation, and is followed by the application of a contrast correction technique. The results from the subtraction were evaluated firstly by the comparison between the actual and the digital sizes corresponding to the holes made by drills in phantoms. The mean error was 4.2%. The method was also applied to actual tooth radiographic images and could detect clearly the effect of treatment of periodontal diseases. It is dependent on the reproducibility of the process of radiographs acquisition and digitization, but the calculated mean error allows to conclude its better efficacy compared to usual procedures in this field. (author)

  6. Sequential analysis of biochemical markers of bone resorption and bone densitometry in multiple myeloma

    DEFF Research Database (Denmark)

    Abildgaard, Niels; Brixen, Kim; Eriksen, Erik Fink

    2004-01-01

    less informative. In Cox analysis, ICTP showed the highest predictive value, but should be replaced with NTx in patients with nephropathy. Pretreatment low lumbar BMD was predictive of early vertebral fractures. INTERPRETATION AND CONCLUSIONS: Sequential DEXA-scans showed heterogeneous local BMD...... changes, and our data do not support routine use of sequential DEXA-scans. However, lumbar DEXA-scans at diagnosis can identify patients with increased risk of early vertebral collapses. Sequential analyses of serum ICTP and urinary NTx are useful for monitoring bone damage....

  7. Effect of local administration of platelet-rich plasma and guided tissue regeneration on the level of bone resorption in early dental implant insertion

    Directory of Open Access Journals (Sweden)

    Duka Miloš

    2008-01-01

    Full Text Available Background/Aim. Osseointegration is a result of cellular migration, differentiation, bone formation, and bone remodeling on the surface of an implant. Each of these processes depends on platelets and blood coagulum. Platelet-rich plasma (PRP is used to improve osseointegration and stability of implants. The aim of the research was to test the influence that PRP and guided tissue regeneration in bone defects have on bone defect filling and the level of bone resorption in early implant insertion. Methods. This experimental study included 10 dogs. A total of 40 BCT implants were inserted, 4 in each dog (two on the left side and two on the right side, with guided tissue regeneration. Radiologic analyses were done immediately after the insertion and 10 weeks after the insertion. Bone defect filling was measured by a graduated probe 10 weeks after the implant insertion. The following protocols were tested: I - PRP in combination with bovine deproteinized bone (BDB and resorptive membrane of bovine origin (RBDM, II - BDB + RBDM, III - PRP + RBDM and IV - RBDM. Results. The applied protocols affected differently the bone defect filling and the level of bone resorption. Significantly better results (the lowest bone resorption were achieved with protocol I (PRP + BDB + RBDM in comparison with protocols III (PRP + RBDM and IV (RBDM, but not with protocol II (BDB + RBDM. On the other hand, no significant difference was found among protocols II (BDB + RBDM, III (PRP + RBDM and IV (RBDM in the level of bone tissue resorption. Conslusion. The bone defect filling was largest and the level of bone resorption was lowest in the protocol with PRP applied in combination with BDB and RBDM.

  8. Angiopoietin-like 4 is over-expressed in rheumatoid arthritis patients: association with pathological bone resorption.

    Directory of Open Access Journals (Sweden)

    Catherine Swales

    Full Text Available Osteoclasts are responsible for the bone loss associated with rheumatoid arthritis (RA. The secreted adipokine angiopoietin-like 4 (ANGPTL4 specifically increases osteoclast-mediated bone resorption. We have investigated expression of ANGPTL4 and its regulatory transcription factor, hypoxia-inducible factor-1 alpha (HIF-1α, in osteoclasts and other cells within rheumatoid synovium. We have also examined whether circulating levels of ANGPTL4 differ in RA patients compared with that in normal controls or patients with osteoarthritis (OA.Immunohistochemical analysis revealed that bone-apposing osteoclasts within the rheumatoid synovium express both ANGPTL4 and HIF-1α. ANGPTL4 was also strongly expressed in synovial lining cells, endothelial cells, stromal cells, CD68+ macrophages and plasma cells within RA synovium. Little ANGPTL4 was evident in normal synovial tissue. This reflected the over-expression of HIF-1α in rheumatoid versus normal synovial tissue. The concentration of ANGPTL4 was higher in both the serum and the synovial fluid of RA patients than in patients with OA or normal controls. High serum ANGPTL4 associated with elevated levels of the serum marker of bone resorption, receptor activator for nuclear factor κB ligand (RANKL.Over-expression of ANGPTL4 in multiple cell types within the rheumatoid synovium potentially provides a local pool of ANGPTL4 to stimulate osteoclast-mediated bone resorption in RA. Additionally, correlation of high serum ANGPTL4 with circulating RANKL suggests that ANGPTL4 may represent a novel marker for bone destruction in RA.

  9. Preventive Effects of Drinking Hydrogen-Rich Water on Gingival Oxidative Stress and Alveolar Bone Resorption in Rats Fed a High-Fat Diet.

    Science.gov (United States)

    Yoneda, Toshiki; Tomofuji, Takaaki; Kunitomo, Muneyoshi; Ekuni, Daisuke; Irie, Koichiro; Azuma, Tetsuji; Machida, Tatsuya; Miyai, Hisataka; Fujimori, Kouhei; Morita, Manabu

    2017-01-13

    Obesity induces gingival oxidative stress, which is involved in the progression of alveolar bone resorption. The antioxidant effect of hydrogen-rich water may attenuate gingival oxidative stress and prevent alveolar bone resorption in cases of obesity. We examined whether hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption in obese rats fed a high-fat diet. Male Fischer 344 rats (n = 18) were divided into three groups of six rats each: a control group (fed a regular diet and drinking distilled water) and two experimental groups (fed a high-fat diet and drinking distilled water or hydrogen-rich water). The level of 8-hydroxydeoxyguanosine was determined to evaluate oxidative stress. The bone mineral density of the alveolar bone was analyzed by micro-computerized tomography. Obese rats, induced by a high-fat diet, showed a higher gingival level of 8-hydroxydeoxyguanosine and a lower level of alveolar bone density compared to the control group. Drinking hydrogen-rich water suppressed body weight gain, lowered gingival level of 8-hydroxydeoxyguanosine, and reduced alveolar bone resorption in rats on a high-fat diet. The results indicate that hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption by limiting obesity.

  10. Preventive Effects of Drinking Hydrogen-Rich Water on Gingival Oxidative Stress and Alveolar Bone Resorption in Rats Fed a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Toshiki Yoneda

    2017-01-01

    Full Text Available Obesity induces gingival oxidative stress, which is involved in the progression of alveolar bone resorption. The antioxidant effect of hydrogen-rich water may attenuate gingival oxidative stress and prevent alveolar bone resorption in cases of obesity. We examined whether hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption in obese rats fed a high-fat diet. Male Fischer 344 rats (n = 18 were divided into three groups of six rats each: a control group (fed a regular diet and drinking distilled water and two experimental groups (fed a high-fat diet and drinking distilled water or hydrogen-rich water. The level of 8-hydroxydeoxyguanosine was determined to evaluate oxidative stress. The bone mineral density of the alveolar bone was analyzed by micro-computerized tomography. Obese rats, induced by a high-fat diet, showed a higher gingival level of 8-hydroxydeoxyguanosine and a lower level of alveolar bone density compared to the control group. Drinking hydrogen-rich water suppressed body weight gain, lowered gingival level of 8-hydroxydeoxyguanosine, and reduced alveolar bone resorption in rats on a high-fat diet. The results indicate that hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption by limiting obesity.

  11. Decreased nitric oxide levels stimulate osteoclastogenesis and bone resorption both in vitro and in vivo on the chick chorioallantoic membrane in association with neoangiogenesis.

    Science.gov (United States)

    Collin-Osdoby, P; Rothe, L; Bekker, S; Anderson, F; Osdoby, P

    2000-03-01

    High nitric oxide (NO) levels inhibit osteoclast (OC)-mediated bone resorption in vivo and in vitro, and nitrate donors protect against estrogen-deficient bone loss in postmenopausal women. Conversely, decreased NO production potentiates OC bone resorption in vitro and is associated with in vivo bone loss in rats and humans. Previously, we reported that bone sections from rats administered aminoguanidine (AG), a selective inhibitor of NO production via inducible NO synthase, exhibited both increased OC resorptive activity as well as greater numbers of OC. Here, we investigated further whether AG promoted osteoclastogenesis, in addition to stimulating mature OC function, using a modified in vivo chick chorioallantoic membrane (CAM) system and an in vitro chick bone marrow OC-like cell developmental model. AG, focally administered in small agarose plugs placed directly adjacent to a bone chip implanted on the CAM, dose-dependently elicited neoangiogenesis while stimulating the number, size, and bone pit resorptive activity of individual OC ectopically formed in vivo. In addition to enhancing OC precursor recruitment via neoangiogenesis, AG also exerted other vascular-independent effects on osteoclastogenesis. Thus, AG promoted the in vitro fusion and formation from bone marrow precursor cells of larger OC-like cells that contained more nuclei per cell and exhibited multiple OC differentiation markers. AG stimulated development was inversely correlated with declining medium nitrite levels. In contrast, three different NO donors each dose-dependently inhibited in vitro OC-like cell development while raising medium nitrite levels. Therefore, NO sensitively regulates OC-mediated bone resorption through affecting OC recruitment (angiogenesis), formation (fusion and differentiation), and bone resorptive activity in vitro and in vivo. Possibly, the stimulation of neoangiogenesis and OC-mediated bone remodeling via AG or other pro-angiogenic agents may find clinical

  12. Effect of Cytokines on Osteoclast Formation and Bone Resorption during Mechanical Force Loading of the Periodontal Membrane

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    Hideki Kitaura

    2014-01-01

    Full Text Available Mechanical force loading exerts important effects on the skeleton by controlling bone mass and strength. Several in vivo experimental models evaluating the effects of mechanical loading on bone metabolism have been reported. Orthodontic tooth movement is a useful model for understanding the mechanism of bone remodeling induced by mechanical loading. In a mouse model of orthodontic tooth movement, TNF-α was expressed and osteoclasts appeared on the compressed side of the periodontal ligament. In TNF-receptor-deficient mice, there was less tooth movement and osteoclast numbers were lower than in wild-type mice. These results suggest that osteoclast formation and bone resorption caused by loading forces on the periodontal ligament depend on TNF-α. Several cytokines are expressed in the periodontal ligament during orthodontic tooth movement. Studies have found that inflammatory cytokines such as IL-12 and IFN-γ strongly inhibit osteoclast formation and tooth movement. Blocking macrophage colony-stimulating factor by using anti-c-Fms antibody also inhibited osteoclast formation and tooth movement. In this review we describe and discuss the effect of cytokines in the periodontal ligament on osteoclast formation and bone resorption during mechanical force loading.

  13. Extracorporeal shock waves alone or combined with raloxifene promote bone formation and suppress resorption in ovariectomized rats

    Science.gov (United States)

    Corrado, Bruno; Pirozzi, Claudio; Paciello, Orlando; Pagano, Teresa Bruna; Russo, Sergio; Calignano, Antonio; Mattace Raso, Giuseppina; Meli, Rosaria

    2017-01-01

    Osteoporosis is a metabolic skeletal disease characterized by an imbalance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation. We examined the beneficial effect of shock waves (SW) alone or in combination with raloxifene (RAL) on bone loss in ovariectomized rats (OVX). Sixteen weeks after surgery, OVX were treated for five weeks with SW at the antero-lateral side of the right hind leg, one session weekly, at 3 Hz (EFD of 0.33 mJ/mm2), or with RAL (5 mg/kg/die, per os) or with SW+RAL. Sera, femurs, tibiae and vertebrae were sampled for following biochemical and histological analysis. SW, alone or combined with RAL, prevented femur weight reduction and the deterioration of trabecular microarchitecture both in femur and vertebrae. All treatments increased Speed of Sound (SoS) values, improving bone mineral density, altered by OVX. Serum parameters involved in bone remodeling (alkaline phosphatase, receptor activator of nuclear factor kappa-B ligand, osteoprotegerin) and osteoblast proliferation (PTH), altered by ovariectomy, were restored by SW and RAL alone or in combination. In tibiae, SW+RAL significantly reduced cathepsin k and TNF-α levels, indicating the inhibition of osteoclast activity, while all treatments significantly increased runt-related transcription factor 2 and bone morphogenetic-2 expression, suggesting an increase in osteoblastogenic activity. Finally, in bone marrow from tibiae, SW or RAL reduced PPARγ and adiponectin transcription, indicating a shift of mesenchymal cells toward osteoblastogenesis, without showing a synergistic effect. Our data indicate SW therapy, alone and in combination with raloxifene, as an innovative strategy to limit the hypoestrogenic bone loss, restoring the balance between bone formation and resorption. PMID:28158228

  14. Analysis of correlation between initial alveolar bone density and apical root resorption after 12 months of orthodontic treatment without extraction

    Directory of Open Access Journals (Sweden)

    Paula Cabrini Scheibel

    2014-10-01

    Full Text Available OBJECTIVE: The aim of the present study was to investigate the correlation between initial alveolar bone density of upper central incisors (ABD-UI and external apical root resorption (EARR after 12 months of orthodontic movement in cases without extraction. METHODS: A total of 47 orthodontic patients 11 years old or older were submitted to periapical radiography of upper incisors prior to treatment (T1 and after 12 months of treatment (T2. ABD-UI and EARR were measured by means of densitometry. RESULTS: No statistically significant correlation was found between initial ABD-UI and EARR at T2 (r = 0.149; p = 0.157. CONCLUSION: Based on the present findings, alveolar density assessed through periapical radiography is not predictive of root resorption after 12 months of orthodontic treatment in cases without extraction.

  15. Blocking antibody to the beta-subunit of FSH prevents bone loss by inhibiting bone resorption and stimulating bone synthesis

    Science.gov (United States)

    Low estrogen levels undoubtedly underlie menopausal bone thinning. However, rapid and profuse bone loss begins three years prior to the last menstrual period, when serum estrogen is relatively normal. We have shown that the pituitary hormone FSH, the levels of which are high during the late peri-men...

  16. Osteoclast cytosolic calcium, regulated by voltage-gated calcium channels and extracellular calcium, controls podosome assembly and bone resorption

    Science.gov (United States)

    Miyauchi, A.; Hruska, K. A.; Greenfield, E. M.; Duncan, R.; Alvarez, J.; Barattolo, R.; Colucci, S.; Zambonin-Zallone, A.; Teitelbaum, S. L.; Teti, A.

    1990-01-01

    The mechanisms of Ca2+ entry and their effects on cell function were investigated in cultured chicken osteoclasts and putative osteoclasts produced by fusion of mononuclear cell precursors. Voltage-gated Ca2+ channels (VGCC) were detected by the effects of membrane depolarization with K+, BAY K 8644, and dihydropyridine antagonists. K+ produced dose-dependent increases of cytosolic calcium ([Ca2+]i) in osteoclasts on glass coverslips. Half-maximal effects were achieved at 70 mM K+. The effects of K+ were completely inhibited by dihydropyridine derivative Ca2+ channel blocking agents. BAY K 8644 (5 X 10(-6) M), a VGCC agonist, stimulated Ca2+ entry which was inhibited by nicardipine. VGCCs were inactivated by the attachment of osteoclasts to bone, indicating a rapid phenotypic change in Ca2+ entry mechanisms associated with adhesion of osteoclasts to their resorption substrate. Increasing extracellular Ca2+ ([Ca2+]e) induced Ca2+ release from intracellular stores and Ca2+ influx. The Ca2+ release was blocked by dantrolene (10(-5) M), and the influx by La3+. The effects of [Ca2+]e on [Ca2+]i suggests the presence of a Ca2+ receptor on the osteoclast cell membrane that could be coupled to mechanisms regulating cell function. Expression of the [Ca2+]e effect on [Ca2+]i was similar in the presence or absence of bone matrix substrate. Each of the mechanisms producing increases in [Ca2+]i, (membrane depolarization, BAY K 8644, and [Ca2+]e) reduced expression of the osteoclast-specific adhesion structure, the podosome. The decrease in podosome expression was mirrored by a 50% decrease in bone resorptive activity. Thus, stimulated increases of osteoclast [Ca2+]i lead to cytoskeletal changes affecting cell adhesion and decreasing bone resorptive activity.

  17. Porphyromonas gingivalis GroEL induces osteoclastogenesis of periodontal ligament cells and enhances alveolar bone resorption in rats.

    Directory of Open Access Journals (Sweden)

    Feng-Yen Lin

    Full Text Available Porphyromonas gingivalis is a major periodontal pathogen that contains a variety of virulence factors. The antibody titer to P. gingivalis GroEL, a homologue of HSP60, is significantly higher in periodontitis patients than in healthy control subjects, suggesting that P. gingivalis GroEL is a potential stimulator of periodontal disease. However, the specific role of GroEL in periodontal disease remains unclear. Here, we investigated the effect of P. gingivalis GroEL on human periodontal ligament (PDL cells in vitro, as well as its effect on alveolar bone resorption in rats in vivo. First, we found that stimulation of PDL cells with recombinant GroEL increased the secretion of the bone resorption-associated cytokines interleukin (IL-6 and IL-8, potentially via NF-κB activation. Furthermore, GroEL could effectively stimulate PDL cell migration, possibly through activation of integrin α1 and α2 mRNA expression as well as cytoskeletal reorganization. Additionally, GroEL may be involved in osteoclastogenesis via receptor activator of nuclear factor κ-B ligand (RANKL activation and alkaline phosphatase (ALP mRNA inhibition in PDL cells. Finally, we inoculated GroEL into rat gingiva, and the results of microcomputed tomography (micro-CT and histomorphometric assays indicated that the administration of GroEL significantly increased inflammation and bone loss. In conclusion, P. gingivalis GroEL may act as a potent virulence factor, contributing to osteoclastogenesis of PDL cells and resulting in periodontal disease with alveolar bone resorption.

  18. Effects of long-term alendronate treatment on bone mineralisation, resorption parameters and biomechanics of single human vertebral trabeculae

    Directory of Open Access Journals (Sweden)

    M Krause

    2014-09-01

    Full Text Available Due to their well-established fracture risk reduction, bisphosphonates are the most frequently used therapeutic agent to treat osteoporosis. Bisphosphonates reduce fracture risk by suppressing bone resorption, but the lower bone turnover could have a negative impact on bone quality at the tissue level. Here, we directly assess the structural and mechanical characteristics of cancellous bone from the lumbar vertebrae (L5 in non-treated osteoporotic controls (n = 21, mid-term alendronate-treated osteoporotic patients (n = 6, and long-term alendronate-treated osteoporotic patients (n = 7. The strength and toughness of single trabeculae were evaluated, while the structure was characterised through measurements of microdamage accumulation, mineralisation distribution, and histological indices. The alendronate-treated cases had a reduced eroded surface (ES/BS, p < 0.001 and a higher bone mineralisation in comparison to non-treated controls (p = 0.037, which is indicative of low turnover associated with treatment. However, the amount of microdamage and the mechanical properties were similar among the control and treatment groups. As the tissue mineral density (TMD increased significantly with alendronate treatment compared to non-treated osteoporotic controls, the reduction in resorption cavities could counterbalance the higher TMD allowing the alendronate-treated bone to maintain its mechanical properties and resist microdamage accumulation. A multivariate analysis of the possible predictors supports the theory that multiple factors (e.g., body mass index, TMD, and ES/BS can impact the mechanical properties. Our results suggest that long-term alendronate treatment shows no adverse impact on mechanical cancellous bone characteristics.

  19. Parthenolide reduces empty lacunae and osteoclastic bone surface resorption induced by polyethylene particles in a murine calvarial model of peri-implant osteolysis.

    Science.gov (United States)

    Zawawi, Muhamad S F; Marino, Victor; Perilli, Egon; Cantley, Melissa D; Xu, Jiake; Purdue, P Edward; Dharmapatni, Anak A S S K; Haynes, David R; Crotti, Tania N

    2015-11-01

    The study aimed to determine the effects of parthenolide (PAR) on bone volume (BV) and bone surface resorption as assessed by live-animal microcomputed tomography (μCT) and possible osteocyte death as indicated by empty lacunae histologically in polyethylene (PE) particle-induced calvarial osteolysis in mice. Baseline μCT scans were conducted 7 days preimplantation of 2 × 10(8) PE particles/mL over the calvariae (day 0). PAR at 1 mg/kg/day was subcutaneously injected on days 0, 4, 7, and 10. At day 14, BV and surface resorption was analyzed with μCT. Calvarial tissue was processed for histomorphometric osteocyte evaluation. Serum was analyzed for type-1 carboxy-terminal collagen crosslinks (CTX-1) and osteoclast associated receptor (OSCAR) levels by ELISA. PE significantly decreased BV (p = 0.0368), increased surface bone resorption area (p = 0.0022), and increased the percentage of empty lacunae (p = 0.0043). Interestingly, PAR significantly reduced the resorption surface area (p = 0.0022) and the percentage of empty osteocyte lacunae (p = 0.0087) in the PE-calvariae, but it did not affect BV, serum CTX-1 or OSCAR levels. The ability of PAR to inhibit PE-induced surface bone erosion may better reflect the in vivo situation, where bone resorption occurs on the surface at the bone-implant interface and may also be related to the role of osteocytes in this pathology.

  20. The carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen in serum as a marker of bone resorption

    DEFF Research Database (Denmark)

    Hassager, C; Jensen, L T; Pødenphant, J

    1994-01-01

    in postmenopausal women with mild osteoporosis, and assessed the effect of hormone replacement therapy (HRT) (2 mg 17 beta-estradiol plus 1 mg norethisterone daily) and anabolic steroid therapy (50 mg nandrolone decanoate (ND) i.m. every 3 weeks) on serum ICTP in two double-blind placebo-controlled studies with 55...... conclude that serum ICTP does reflect bone metabolism in postmenopausal osteoporosis, but it is not a sensitive marker of the changes in bone resorption induced by hormone replacement therapy, and it does not correspond with other measures of bone resorption during anabolic steroid therapy....

  1. Commercial Honeybush (Cyclopia spp.) Tea Extract Inhibits Osteoclast Formation and Bone Resorption in RAW264.7 Murine Macrophages-An in vitro Study.

    Science.gov (United States)

    Visagie, Amcois; Kasonga, Abe; Deepak, Vishwa; Moosa, Shaakirah; Marais, Sumari; Kruger, Marlena C; Coetzee, Magdalena

    2015-10-28

    Honeybush tea, a sweet tasting caffeine-free tea that is indigenous to South Africa, is rich in bioactive compounds that may have beneficial health effects. Bone remodeling is a physiological process that involves the synthesis of bone matrix by osteoblasts and resorption of bone by osteoclasts. When resorption exceeds formation, bone remodeling can be disrupted resulting in bone diseases such as osteoporosis. Osteoclasts are multinucleated cells derived from hematopoietic precursors of monocytic lineage. These precursors fuse and differentiate into mature osteoclasts in the presence of receptor activator of NF-kB ligand (RANKL), produced by osteoblasts. In this study, the in vitro effects of an aqueous extract of fermented honeybush tea were examined on osteoclast formation and bone resorption in RAW264.7 murine macrophages. We found that commercial honeybush tea extract inhibited osteoclast formation and TRAP activity which was accompanied by reduced bone resorption and disruption of characteristic cytoskeletal elements of mature osteoclasts without cytotoxicity. Furthermore, honeybush tea extract decreased expression of key osteoclast specific genes, matrix metalloproteinase-9 (MMP-9), tartrate resistant acid phosphatase (TRAP) and cathepsin K. This study demonstrates for the first time that honeybush tea may have potential anti-osteoclastogenic effects and therefore should be further explored for its beneficial effects on bone.

  2. Commercial Honeybush (Cyclopia spp. Tea Extract Inhibits Osteoclast Formation and Bone Resorption in RAW264.7 Murine Macrophages—An in vitro Study

    Directory of Open Access Journals (Sweden)

    Amcois Visagie

    2015-10-01

    Full Text Available Honeybush tea, a sweet tasting caffeine-free tea that is indigenous to South Africa, is rich in bioactive compounds that may have beneficial health effects. Bone remodeling is a physiological process that involves the synthesis of bone matrix by osteoblasts and resorption of bone by osteoclasts. When resorption exceeds formation, bone remodeling can be disrupted resulting in bone diseases such as osteoporosis. Osteoclasts are multinucleated cells derived from hematopoietic precursors of monocytic lineage. These precursors fuse and differentiate into mature osteoclasts in the presence of receptor activator of NF-kB ligand (RANKL, produced by osteoblasts. In this study, the in vitro effects of an aqueous extract of fermented honeybush tea were examined on osteoclast formation and bone resorption in RAW264.7 murine macrophages. We found that commercial honeybush tea extract inhibited osteoclast formation and TRAP activity which was accompanied by reduced bone resorption and disruption of characteristic cytoskeletal elements of mature osteoclasts without cytotoxicity. Furthermore, honeybush tea extract decreased expression of key osteoclast specific genes, matrix metalloproteinase-9 (MMP-9, tartrate resistant acid phosphatase (TRAP and cathepsin K. This study demonstrates for the first time that honeybush tea may have potential anti-osteoclastogenic effects and therefore should be further explored for its beneficial effects on bone.

  3. Predictive value of ridge dimensions on autologous bone graft resorption in staged maxillary sinus augmentation surgery using Cone-Beam CT.

    NARCIS (Netherlands)

    Klijn, R.J.; Beucken, J.J.J.P van den; Bronkhorst, E.M.; Berge, S.J.; Meijer, G.J.; Jansen, J.B.M.J.

    2012-01-01

    INTRODUCTION: No studies are available that provide predictive parameters regarding the expected amount of resorption after maxillary sinus augmentation surgery using autologous bone grafts. Therefore, the aim of this study was to determine parameters influencing the outcome of the bone graft resorp

  4. Inhibition of osteocyte apoptosis prevents the increase in osteocytic receptor activator of nuclear factor κB ligand (RANKL) but does not stop bone resorption or the loss of bone induced by unloading.

    Science.gov (United States)

    Plotkin, Lilian I; Gortazar, Arancha R; Davis, Hannah M; Condon, Keith W; Gabilondo, Hugo; Maycas, Marta; Allen, Matthew R; Bellido, Teresita

    2015-07-31

    Apoptosis of osteocytes and osteoblasts precedes bone resorption and bone loss with reduced mechanical stimulation, and receptor activator of NF-κB ligand (RANKL) expression is increased with unloading in mice. Because osteocytes are major RANKL producers, we hypothesized that apoptotic osteocytes signal to neighboring osteocytes to increase RANKL expression, which, in turn, increases osteoclastogenesis and bone resorption. The traditional bisphosphonate (BP) alendronate (Aln) or IG9402, a BP analog that does not inhibit resorption, prevented the increase in osteocyte apoptosis and osteocytic RANKL expression. The BPs also inhibited osteoblast apoptosis but did not prevent the increase in osteoblastic RANKL. Unloaded mice exhibited high serum levels of the bone resorption marker C-telopeptide fragments of type I collagen (CTX), elevated osteoclastogenesis, and increased osteoclasts in bone. Aln, but not IG9402, prevented all of these effects. In addition, Aln prevented the reduction in spinal and femoral bone mineral density, spinal bone volume/tissue volume, trabecular thickness, mechanical strength, and material strength induced by unloading. Although IG9402 did not prevent the loss of bone mass, it partially prevented the loss of strength, suggesting a contribution of osteocyte viability to strength independent of bone mass. These results demonstrate that osteocyte apoptosis leads to increased osteocytic RANKL. However, blockade of these events is not sufficient to restrain osteoclast formation, inhibit resorption, or stop bone loss induced by skeletal unloading.

  5. Influence of Material Properties on Rate of Resorption of Two Bone Graft Materials after Sinus Lift Using Radiographic Assessment

    Directory of Open Access Journals (Sweden)

    Fawzi Riachi

    2012-01-01

    Full Text Available Purpose. The aim of this study was to investigate the influence of chemical and physical properties of two graft materials on the rate of resorption. Materials and Methods. Direct sinus graft procedure was performed on 22 patients intended for implant placement. Two types of graft materials were used (Bio-Oss and Cerabone and after 8 months healing time the implants were inserted. Radiographic assessment was performed over the period of four years. Particle size, rate of calcium release, and size and type of crystal structure of each graft were evaluated. Results. The average particle size of Bio-Oss (1 mm was much smaller compared to Cerabone (2.7 mm. The amount of calcium release due to dissolution of material in water was much higher for Bio-oss compared to Cerabone. X-ray image analysis revealed that Bio-Oss demonstrated significantly higher volumetric loss (33.4 ± 3.1% of initial graft size compared to Cerabone (23.4 ± 3.6%. The greatest amount of vertical loss of graft material volume was observed after one year of surgery. Conclusion. The chemical and physical properties of bone graft material significantly influence resorption rate of bone graft materials used for sinus augmentation.

  6. Photoelastic stress analysis of endodontically treated teeth restored with different post systems: normal and alveolar bone resorption cases.

    Science.gov (United States)

    Ma, Jinbao; Miura, Hiroyuki; Okada, Daizo; Yusa, Koichiro

    2011-01-01

    The present study examined the influence of different post materials and their lengths on the mechanical stress of endodontically treated incisor roots in two alveolar bone conditions. Two-dimensional photoelastic models were fabricated to simulate the endodontically treated maxillary central incisors restored with three kinds of posts materials (low Young's modulus glass fiber post, high Young's modulus glass fiber post, and prefabricated stainless steel post) and two post lengths (8 and 4 mm). Completed models were placed in a transmission polariscope and loaded with a static force of 150 N at 45° to the tooth axis. Photoelastic photographs and the magnitudes of fringe order revealed stress distribution in the root, and suggest that the glass fiber post with a low Young's modulus and long length can reduce the stress concentration both in normal and alveolar bone resorption conditions.

  7. Actin-binding protein coronin 1A controls osteoclastic bone resorption by regulating lysosomal secretion of cathepsin K

    Science.gov (United States)

    Ohmae, Saori; Noma, Naruto; Toyomoto, Masayasu; Shinohara, Masahiro; Takeiri, Masatoshi; Fuji, Hiroaki; Takemoto, Kenji; Iwaisako, Keiko; Fujita, Tomoko; Takeda, Norihiko; Kawatani, Makoto; Aoyama, Mineyoshi; Hagiwara, Masatoshi; Ishihama, Yasushi; Asagiri, Masataka

    2017-01-01

    Osteoclasts degrade bone matrix proteins via the secretion of lysosomal enzymes. However, the precise mechanisms by which lysosomal components are transported and fused to the bone-apposed plasma membrane, termed ruffled border membrane, remain elusive. Here, we identified coronin 1A as a negative regulator of exocytotic release of cathepsin K, one of the most important bone-degrading enzymes in osteoclasts. The modulation of coronin 1A expression did not alter osteoclast differentiation and extracellular acidification, but strongly affected the secretion of cathepsin K and osteoclast bone-resorption activity, suggesting the coronin 1A-mediated regulation of lysosomal trafficking and protease exocytosis. Further analyses suggested that coronin 1A prevented the lipidation-mediated sorting of the autophagy-related protein LC3 to the ruffled border and attenuated lysosome–plasma membrane fusion. In this process, the interactions between coronin 1A and actin were crucial. Collectively, our findings indicate that coronin 1A is a pivotal component that regulates lysosomal fusion and the secretion pathway in osteoclast-lineage cells and may provide a novel therapeutic target for bone diseases. PMID:28300073

  8. Does the cortical bone resorption rate change due to 90Sr-radiation exposure? Analysis of data from Techa Riverside residents

    Energy Technology Data Exchange (ETDEWEB)

    Tolstykh, E I; Shagina, N B; Degteva, M O; Anspaugh, L R; Napier, Bruce A

    2011-08-01

    The Mayak Production Association released large amounts of 90Sr into the Techa River (Southern Urals, Russia) with peak amounts in 1950-1951. Techa Riverside residents ingested an average of about 3,000 kBq of 90Sr. The 90Sr-body burden of approximately 15,000 individuals has been measured in the Urals Research Center for Radiation Medicine in 1974-1997 with use of a special whole-body counter (WBC). Strontium-90 had mainly deposited in the cortical part of the skeleton by 25 years following intake, and 90Sr elimination occurs as a result of cortical bone resorption. The effect of 90Sr-radiation exposure on the rate of cortical bone resorption was studied. Data on 2,022 WBC measurements were selected for 207 adult persons, who were measured three or more times before they were 50-55 years old. The individual-resorption rates were calculated with the rate of strontium recirculation evaluated as 0.0018 year-1. Individual absorbed doses in red bone marrow (RBM) and bone surface (BS) were also calculated. Statistically significant negative relationships of cortical bone resorption rate were discovered related to 90Sr-body burden and dose absorbed in the RBM or the BS. The response appears to have a threshold of about 1.5-Gy RBM dose. The radiation induced decrease in bone resorption rate may not be significant in terms of health. However, a decrease in bone remodeling rate can be among several causes of an increased level of degenerative dystrophic bone pathology in exposed persons.

  9. Markers of bone resorption and calcium metabolism are related to dietary intake patterns in male and female bed rest subjects

    Science.gov (United States)

    Smith, Scott M.; Zwart, S. R.; Hargens, A. r.

    2006-01-01

    Dietary potassium and protein intakes predict net endogenous acid production in humans. Intracellular buffers, including exchangeable bone mineral, play a crucial role in balancing chronic acid-base perturbations in the body; subsequently, chronic acid loads can potentially contribute to bone loss. Bone is lost during space flight, and a dietary countermeasure would be desirable for many reasons. We studied the ability of diet protein and potassium to predict levels of bone resorption markers in males and females. Identical twin pairs (8 M, 7 F) were assigned to 2 groups: bed rest (sedentary, SED) or bed rest with supine treadmill exercise in a lower body negative pressure chamber (EX). Diet was controlled for 3 d before and 30 d of bed rest (BR). Urinary Ca, N-telopeptide (NTX), and pyridinium crosslinks (PYD) were measured before and on days 5, 12, 19, and 26 of BR. Data were analyzed by Pearson correlation (P<0.05). The ratio of dietary animal protein/potassium intake was not correlated with NTX before BR for males or females, but they were positively correlated in both groups of males during bed rest. Dietary animal protein/potassium and urine Ca were correlated before and during bed rest for the males, and only during bed rest for the females. Conversely, the ratio of dietary vegetable protein/potassium intake was negatively correlated with urinary calcium during bed rest for the females, but there was no relationship between vegetable protein/potassium intake and bone markers for the males. These data suggest that the ratio of animal protein/potassium intake may affect bone, particularly in bed rest subjects. These data show that the type of protein and gender may be additional factors that modulate the effect of diet on bone metabolism during bed rest. Altering this ratio may help prevent bone loss on Earth and during space flight.

  10. Markers of bone resorption and calcium metabolism are related to dietary intake patterns in male and female bed rest subjects

    Science.gov (United States)

    Smith, Scott M.; Zwart, S. R.; Hargens, A. r.

    2006-01-01

    Dietary potassium and protein intakes predict net endogenous acid production in humans. Intracellular buffers, including exchangeable bone mineral, play a crucial role in balancing chronic acid-base perturbations in the body; subsequently, chronic acid loads can potentially contribute to bone loss. Bone is lost during space flight, and a dietary countermeasure would be desirable for many reasons. We studied the ability of diet protein and potassium to predict levels of bone resorption markers in males and females. Identical twin pairs (8 M, 7 F) were assigned to 2 groups: bed rest (sedentary, SED) or bed rest with supine treadmill exercise in a lower body negative pressure chamber (EX). Diet was controlled for 3 d before and 30 d of bed rest (BR). Urinary Ca, N-telopeptide (NTX), and pyridinium crosslinks (PYD) were measured before and on days 5, 12, 19, and 26 of BR. Data were analyzed by Pearson correlation (Pdietary animal protein/potassium intake was not correlated with NTX before BR for males or females, but they were positively correlated in both groups of males during bed rest. Dietary animal protein/potassium and urine Ca were correlated before and during bed rest for the males, and only during bed rest for the females. Conversely, the ratio of dietary vegetable protein/potassium intake was negatively correlated with urinary calcium during bed rest for the females, but there was no relationship between vegetable protein/potassium intake and bone markers for the males. These data suggest that the ratio of animal protein/potassium intake may affect bone, particularly in bed rest subjects. These data show that the type of protein and gender may be additional factors that modulate the effect of diet on bone metabolism during bed rest. Altering this ratio may help prevent bone loss on Earth and during space flight.

  11. A supra-cellular model for coupling of bone resorption to formation during remodeling

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Pennypacker, Brenda L

    2014-01-01

    by the osteoclasts. However, the osteoclasts are separated from the mature bone forming osteoblasts in time and space. Therefore the target cell of these osteoclastic factors has remained unknown. Recent explorations of the physical microenvironment of osteoclasts revealed a cell layer lining the bone marrow......The bone matrix is maintained functional through the combined action of bone resorbing osteoclasts and bone forming osteoblasts, in so-called bone remodeling units. The coupling of these two activities is critical for securing bone replenishment and involves osteogenic factors released...

  12. Effects of treatment with glucagon-like peptide-2 on bone resorption in colectomized patients with distal ileostomy or jejunostomy and short-bowel syndrome

    DEFF Research Database (Denmark)

    Gottschalck, I.B.; Jeppesen, Palle Bekker; Hartmann, B.;

    2008-01-01

    OBJECTIVE: The gut hormone GLP-2 (glucagon-like peptide-2) seems to be involved in the circadian pattern of bone resorption, whereas parathyroid hormone (PTH) is an established key hormone in bone turnover. Endogenous GLP-2 secretion is lacking in colectomized patients with short-bowel syndrome (...... and therefore precludes treatment of their osteopenia with GLP-2. The anti-resorptive response to GLP-2 seems to require an intact small intestine and may involve suppression of PTH secretion Udgivelsesdato: 2008......OBJECTIVE: The gut hormone GLP-2 (glucagon-like peptide-2) seems to be involved in the circadian pattern of bone resorption, whereas parathyroid hormone (PTH) is an established key hormone in bone turnover. Endogenous GLP-2 secretion is lacking in colectomized patients with short-bowel syndrome...... (SBS) and they have reduced bone mineral density (BMD). The aim of the study was to investigate the anti-resorptive effect (assessed by s-CTX) of 14 days of GLP-2 treatment in these patients and to determine whether 56 days of treatment would improve BMD. PTH secretion in response to GLP-2 was also...

  13. Effects of treatment with glucagon-like peptide-2 on bone resorption in colectomized patients with distal ileostomy or jejunostomy and short-bowel syndrome

    DEFF Research Database (Denmark)

    Gottschalck, Ida B; Jeppesen, Palle B; Hartmann, Bolette;

    2008-01-01

    OBJECTIVE: The gut hormone GLP-2 (glucagon-like peptide-2) seems to be involved in the circadian pattern of bone resorption, whereas parathyroid hormone (PTH) is an established key hormone in bone turnover. Endogenous GLP-2 secretion is lacking in colectomized patients with short-bowel syndrome (...... and therefore precludes treatment of their osteopenia with GLP-2. The anti-resorptive response to GLP-2 seems to require an intact small intestine and may involve suppression of PTH secretion.......OBJECTIVE: The gut hormone GLP-2 (glucagon-like peptide-2) seems to be involved in the circadian pattern of bone resorption, whereas parathyroid hormone (PTH) is an established key hormone in bone turnover. Endogenous GLP-2 secretion is lacking in colectomized patients with short-bowel syndrome...... (SBS) and they have reduced bone mineral density (BMD). The aim of the study was to investigate the anti-resorptive effect (assessed by s-CTX) of 14 days of GLP-2 treatment in these patients and to determine whether 56 days of treatment would improve BMD. PTH secretion in response to GLP-2 was also...

  14. Evidence that treatment with monophasic oral contraceptive formulations containing ethinylestradiol plus gestodene reduces bone resorption in young women.

    Science.gov (United States)

    Paoletti, A M; Orrù, M; Floris, S; Mannias, M; Vacca, A M; Ajossa, S; Guerriero, S; Melis, G B

    2000-04-01

    The aim of the study was to evaluate if a pill containing the same dose of the same type of progestin compound (gestodene, GES, 75 microg) but different doses of ethinylestradiol (EE2) (20 or 30 microg) differently influences specific markers of bone resorption (urinary levels of pyridinoline (PYR) and dexoxypyridinoline (D-PYR)). During the 12 months of the study a significant decrease of urinary levels of PYR and D-PYR was found in 2 groups of young post-adolescent women taking the pills with 20 and 30 microg of EE2 in comparison with control women (subjects of the same age group with normal menstrual cycle who did not use contraception). In women taking pills with 20 or 30 microg EE2, the levels of sex hormone-binding globulin (SHBG) significantly increased during treatment in comparison with baseline, whereas in the same time period no changes occurred in control women. These findings suggest that similar to the pill containing 30 microg EE2, the lower dosage of the EE2 pill (20 microg) is also capable of reducing bone resorption. Twenty and 30 microg EE2 pills exert the same biological estrogenic effect. In fact, SHBG levels significantly increased with both pills. However, an additional effect of the progestin compound that could act directly on progestin or estrogen receptors of bone cannot be excluded. Since contraception with a pill containing the lowest estrogen dose is associated with the lowest incidence of side effects, these findings further suggest a pill containing 20 microg EE2 for young post-adolescent women would be the best choice.

  15. 破骨细胞骨吸收功能的检测方法%The detection methods of bone resorption function of osteoclasts

    Institute of Scientific and Technical Information of China (English)

    李鹏辉; 田宗成; 商澎

    2012-01-01

    Osteoclast, which is multinucleated bone tissue cell, plays a significant role in the process of bone resorption. The dysfunction of bone resorption of osteoclast could result in a series of clinical diseases, such as osteoporosis, prosthesis loose after joint replacement, osteosclerosis and periodontal disease, etc. Further research on bone resorption function of osteoclast is essential for the prevention and cure of bone diseases. The detection method of bone resorption function of osteoclast is considered to be a limiting factor for the research on osteoclast. For this reason, this paper reviewed the detection methods of bone resorption function of osteoclast.%破骨细胞是一种多核的,具有骨吸收功能的骨组织细胞,在骨吸收过程中起着至关重要的作用.破骨细胞骨吸收功能的异常会引发一系列的临床病症,如骨质疏松症、关节置换术后假体松动、骨硬化症和牙周病变等.破骨细胞骨吸收功能的进一步研究对于各类骨疾病的防治具有重要的意义.然而破骨细胞骨吸收功能的检测方法一直以来是制约破骨细胞研究的瓶颈之一.为此,围绕破骨细胞骨吸收功能的检测方法做一综述.

  16. Prevention of wear particle-induced osteolysis by a novel V-ATPase inhibitor saliphenylhalamide through inhibition of osteoclast bone resorption.

    Directory of Open Access Journals (Sweden)

    An Qin

    Full Text Available Wear particle-induced peri-implant loosening (Aseptic prosthetic loosening is one of the most common causes of total joint arthroplasty. It is well established that extensive bone destruction (osteolysis by osteoclasts is responsible for wear particle-induced peri-implant loosening. Thus, inhibition of osteoclastic bone resorption should prevent wear particle induced osteolysis and may serve as a potential therapeutic avenue for prosthetic loosening. Here, we demonstrate for the first time that saliphenylhalamide, a new V-ATPase inhibitor attenuates wear particle-induced osteolysis in a mouse calvarial model. In vitro biochemical and morphological assays revealed that the inhibition of osteolysis is partially attributed to a disruption in osteoclast acidification and polarization, both a prerequisite for osteoclast bone resorption. Interestingly, the V-ATPase inhibitor also impaired osteoclast differentiation via the inhibition of RANKL-induced NF-κB and ERK signaling pathways. In conclusion, we showed that saliphenylhalamide affected multiple physiological processes including osteoclast differentiation, acidification and polarization, leading to inhibition of osteoclast bone resorption in vitro and wear particle-induced osteolysis in vivo. The results of the study provide proof that the new generation V-ATPase inhibitors, such as saliphenylhalamide, are potential anti-resorptive agents for treatment of peri-implant osteolysis.

  17. Dietary Zinc Reduces Osteoclast Resorption Activities and Increases Markers of Osteoblast Differentiation, Matrix Maturation, and Mineralization in the Long Bones of Growing Rats

    Science.gov (United States)

    The nutritional influence of zinc (Zn) on markers of bone extracellular matrix (ECM) resorption and mineralization was investigated in growing rats. Thirty male weanling rats were randomly assigned to consume AIN-93G based diets containing 2.5, 5, 7.5, 15, or 30 µg Zn/g diet for 24 d. Femur Zn incre...

  18. Phosphorylated Peptides from Antarctic Krill (Euphausia superba) Prevent Estrogen Deficiency Induced Osteoporosis by Inhibiting Bone Resorption in Ovariectomized Rats.

    Science.gov (United States)

    Xia, Guanghua; Zhao, Yanlei; Yu, Zhe; Tian, Yingying; Wang, Yiming; Wang, Shanshan; Wang, Jingfeng; Xue, Changhu

    2015-11-04

    In the current study, we investigated the improvement of phosphorylated peptides from Antarctic krill Euphausia superba (PP-AKP) on osteoporosis in ovariectomized rats. PP-AKP was supplemented to ovariectomized Sprague-Dawley rats for 90 days. The results showed that PP-AKP treatment remarkably prevented the reduction of bone mass and improved cancellous bone structure and biochemical properties. PP-AKP also significantly decreased serum contents of tartrate-resistant acid phosphatase (TRACP), cathepsin K (Cath-k), matrix metalloproteinases-9 (MMP-9), deoxypyridinoline (DPD), C-terminal telopeptide of collagen I (CTX-1), Ca, and P. Mechanism investigation revealed that PP-AKP significantly increased the osteoprotegerin (OPG)/receptor activator of nuclear factor κB ligand (RANKL) ratio in mRNA expression, protein expression, and serum content. Further research suggested that NF-κB signaling pathways were inhibited by suppressing the mRNA and protein expressions of nuclear factor of activated T-cells (NFATc1) and tumor necrosis factor receptor-associated factor 6 (TRAF6), diminishing the mRNA expression and phosphorylation of nuclear factor κB p65 (NF-κB p65), three key transcription factors in NF-κB pathways. These results suggest that PP-AKP can improve osteoporosis by inhibiting bone resorption via suppressing the activation of osteoclastogenesis related NF-κB pathways.

  19. Effects of a Mikania laevigata extract on bone resorption and RANKL expression during experimental periodontitis in rats

    Directory of Open Access Journals (Sweden)

    Bruno B. Benatti

    2012-06-01

    Full Text Available OBJECTIVES: The Mikania laevigata extract (MLE (popularly known in Brazil as "guaco" possesses anti-inflammatory properties. In the present study we tested the effects of MLE in a periodontitis experimental model in rats. We also investigated possible mechanisms underlying such effects. MATERIAL AND METHODS: Periodontal disease was induced by a ligature placed around the mandibular first molars of each animal. Male Wistar rats were divided into 4 groups: non-ligated animals treated with vehicle; non-ligated animals treated with MLE (10 mg/kg, daily; ligature-induced animals treated with vehicle and ligature-induced animals treated with MLE (10 mg/kg, daily. Thirty days after the induction of periodontal disease, the animals were euthanized and mandibles and gingival tissues removed for further analysis. RESULTS: Morphometric analysis of alveolar bone loss demonstrated that MLE-treated animals presented a decreased alveolar bone loss and a lower expression of the activator of nuclear factor-κB ligand (RANKL measured by immunohistochemistry. Moreover, gingival tissues from the MLE-treated group showed decreased neutrophil migration myeloperoxidase (MPO assay. CONCLUSIONS: These results indicate that MLE may be useful to control bone resorption during progression of experimental periodontitis in rats.

  20. Feeding blueberry diets dose-dependently inhibits bone resorption in young rats

    Science.gov (United States)

    Nutritional status is a critical factor that influences bone development. We previously reported that weanling rats fed AIN-93G semi-purified diets supplemented with 10% whole blueberry (BB) powder for only two weeks beginning on postnatal day 21 (PND21) significantly promoted bone formation. Howeve...

  1. Expression of metastasin S100A4 is essential for bone resorption and regulates osteoclast function

    DEFF Research Database (Denmark)

    Erlandsson, Malin C; Svensson, M; Jonsson, Ing-Marie

    2013-01-01

    S100A4 is a Ca-binding protein that regulates cell growth, survival, and motility. The abundant expression of S100A4 in rheumatiod arthritis contributes to the invasive growth of joint tissue and to bone damage. In the present study, we analysed the role of S100A4 in bone homeostasis....

  2. Correlation between Density and Resorption of Fresh-Frozen and Autogenous Bone Grafts

    Directory of Open Access Journals (Sweden)

    Simone Lumetti

    2014-01-01

    Full Text Available Trial Design. This analysis compared the outcome of fresh-frozen versus autologous bone block grafts for horizontal ridge augmentation in patients with Cawood and Howell class IV atrophies. Methods. Seventeen patients received autologous grafts and 21 patients received fresh-frozen bone grafts. Patients underwent CT scans 1 week and 6 months after surgery for graft volume and density analysis. Results. Two autologous and 3 fresh-frozen grafts failed. Autologous and fresh-frozen grafts lost, respectively, 28% and 46% of their initial volume (P=0.028. It is noteworthy that less dense fresh-frozen blocks lost more volume than denser grafts (61% versus 16%. Conclusions. According to these 6-month results, only denser fresh-frozen bone graft may be an acceptable alternative to autologous bone for horizontal ridge augmentation. Further studies are needed to investigate its behaviour at longer time points.

  3. Progress on Action of Cathepsin K in Bone Resorption%组织蛋白酶K在骨吸收中的作用研究进展

    Institute of Scientific and Technical Information of China (English)

    王东; 顾建红; 刘宗平

    2014-01-01

    组织蛋白酶 K(Cathepsin K,CK)是一种溶酶体半胱氨酸蛋白酶,属于番木瓜蛋白酶超家族。在破骨细胞(osteoclast,OC)介导的骨吸收过程中有效降解骨组织中的基质蛋白,在骨吸收过程中发挥重要作用。研究 CK 在骨吸收中的重要性,为治疗骨代谢疾病开辟了新的途径。论文就组织蛋白酶 K 的结构和功能及在骨吸收过程中与破骨细胞的相互作用和表达水平的调控机制进行了阐述。%Cathepsin K is one of lysosomal cysteine proteases,belongs to the papaya protease superfamily,highly expressed in the process of bone resorption mediated by osteoclasts and degrade matrix proteins in bone tissue ef-fectively,plays a significant role in the process on bone resorption.Study of the importance of cathepsin k in bone resorption opened up a new approach to metabolic bone disease treatment.In this mini-review,we mainly focused on the structure and function of cathepsin K and the interaction with osteoclast,the regulation mechanisms of ex-pression levels in the process of bone resorption.

  4. Methanol Extract of Euchelus asper Prevents Bone Resorption in Ovariectomised Mice Model

    Directory of Open Access Journals (Sweden)

    Babita Balakrishnan

    2014-01-01

    Full Text Available Marine molluscs are widely distributed throughout the world and many bioactive compounds exhibiting antiviral, antitumor, antileukemic, and antibacterial activity have been reported worldwide. The present study was designed to investigate the beneficial effect of methanol extract of Euchelus asper (EAME on estrogen deficiency induced osteoporosis in ovariectomised mice model. Forty-two female Swiss albino mice were randomly assigned into Sham operated (Sham group and six ovariectomised (OVX subgroups such as OVX with vehicle (OVX; OVX with estradiol (2 mg/kg/day; OVX with EAME of graded doses (25, 50, 100, and 200 mg/kg/day. Bone turnover markers like serum alkaline phosphatase (ALP, serum acid phosphatase (ACP, serum calcium, and histological investigations of tibia and uterus were analysed. Metaphyseal DNA content of the femur bone was also studied. Antiosteoclastogenic activity of EAME was examined. Administration of EAME was able to reduce the increased bone turnover markers in the ovariectomised mice. Histomorphometric analysis revealed an increase in bone trabeculation and restoration of trabecular separation by EAME treatment. Metaphyseal DNA content of the femur of the OVX mice was increased by EAME administration. EAME also showed a potent antiosteoclastogenic behaviour. Thus, the present study reveals that EAME was able to successfully reduce the estrogen deficiency induced bone loss.

  5. Methanol Extract of Euchelus asper Prevents Bone Resorption in Ovariectomised Mice Model

    Science.gov (United States)

    Balakrishnan, Babita; Chiplunkar, Shubhada Vivek; Indap, Madhavi Manohar

    2014-01-01

    Marine molluscs are widely distributed throughout the world and many bioactive compounds exhibiting antiviral, antitumor, antileukemic, and antibacterial activity have been reported worldwide. The present study was designed to investigate the beneficial effect of methanol extract of Euchelus asper (EAME) on estrogen deficiency induced osteoporosis in ovariectomised mice model. Forty-two female Swiss albino mice were randomly assigned into Sham operated (Sham) group and six ovariectomised (OVX) subgroups such as OVX with vehicle (OVX); OVX with estradiol (2 mg/kg/day); OVX with EAME of graded doses (25, 50, 100, and 200 mg/kg/day). Bone turnover markers like serum alkaline phosphatase (ALP), serum acid phosphatase (ACP), serum calcium, and histological investigations of tibia and uterus were analysed. Metaphyseal DNA content of the femur bone was also studied. Antiosteoclastogenic activity of EAME was examined. Administration of EAME was able to reduce the increased bone turnover markers in the ovariectomised mice. Histomorphometric analysis revealed an increase in bone trabeculation and restoration of trabecular separation by EAME treatment. Metaphyseal DNA content of the femur of the OVX mice was increased by EAME administration. EAME also showed a potent antiosteoclastogenic behaviour. Thus, the present study reveals that EAME was able to successfully reduce the estrogen deficiency induced bone loss. PMID:24995144

  6. Minodronic acid induces morphological changes in osteoclasts at bone resorption sites and reaches a level required for antagonism of purinergic P2X2/3 receptors.

    Science.gov (United States)

    Tanaka, Makoto; Hosoya, Akihiro; Mori, Hiroshi; Kayasuga, Ryoji; Nakamura, Hiroaki; Ozawa, Hidehiro

    2017-02-27

    Minodronic acid is an aminobisphosphonate that is an antagonist of purinergic P2X2/3 receptors involved in pain. The aim of this study was to investigate the action and distribution of minodronic acid and the potential for P2X2/3 receptor antagonism based on the estimated concentration of minodronic acid. Microlocalization of radiolabeled minodronic acid was examined in the femur of neonatal rats. The bone-binding characteristics of minodronic acid and morphological changes in osteoclasts were analyzed in vitro. The minodronic acid concentration around bone resorption lacunae was predicted based on bone binding and the shape of lacunae. In microautoradiography, radioactive silver grains were abundant in bone-attached osteoclasts and were detected in calcified and ossification zones and in the cytoplasm of osteoclasts but not in the hypertrophic cartilage zone. In an osteoclast culture with 1 µM minodronic acid, 65% of minodronic acid was bound to bone, and C-terminal cross-linking telopeptide release was inhibited by 96%. Cultured osteoclasts without minodronic acid treatment formed ruffled borders and bone resorption lacunae and had rich cytoplasm, whereas those treated with 1 µM minodronic acid were not multinucleated, stained densely with toluidine blue, and were detached from the bone surface. In the 1 µM culture, the estimated minodronic acid concentration in resorption lacunae was 880 µM, which is higher than the IC50 for minodronic acid antagonism of P2X2/3 receptors. Thus, inhibition of P2X2/3 receptors around osteoclasts may contribute to the analgesic effect of minodronic acid.

  7. Staphylococcus aureus Biofilms Decrease Osteoblast Viability, Inhibits Osteogenic Differentiation, and Increases Bone Resorption in vitro

    Science.gov (United States)

    2013-06-01

    oxidation was the only variable modification considered. Maximum missed cleavages for trypsin was set at 1, peptide charge at 2+ and 3+, peptide tolerance...been shown to be strong predictors of rapid and persistent bone loss in rheumatoid arthritis, osteoporosis , and periodontal disease [22,54...FA: Osteomyelitis. Lancet 2004, 364:369–379. 2. Conterno LO, da Silva Filho CR: Antibiotics for treating chronic osteomyelitis in adults . Cochrane

  8. Nondigestible oligosaccharides increase calcium absorption and suppress bone resorption in ovariectomized rats.

    Science.gov (United States)

    Zafar, Tasleem A; Weaver, Connie M; Zhao, Yongdong; Martin, Berdine R; Wastney, Meryl E

    2004-02-01

    Nondigestible oligosaccharides (NDO) including inulin and fructooligosaccharides (FOS) have been reported to stimulate calcium absorption. Here we report the effect of a mixture of inulin and FOS (Raftilose Synergy 1, Orafti) on calcium and bone metabolism in ovariectomized (OVX) rats. OVX rats (6 mo old) were fed a semipurified diet for 3 mo in our animal care laboratory for stabilization after ovariectomy. They were then divided into two groups (n = 13/group) and fed either a control or a NDO-supplemented diet (55 g/kg) for 21 d. Catheters were placed in their jugular veins. After 2 d, a tracer ((45)Ca) was administered by gavage or i.v. and blood was sampled for up to 300 min. Urine and fecal samples were collected for 4 d after (45)Ca administration. Femurs were measured for bone mineral density (BMD), breaking strength, and total calcium. Calcium absorption, femoral calcium content, BMD, and bone balance (V(bal)) were significantly increased (P calcium absorption and retention in ovariectomized rats.

  9. Effect of microgravity and mechanical stimulation on the in vitro mineralization and resorption of fetal mouse long bones (7-IML-1)

    Science.gov (United States)

    Veldhuijzen, J. Paul

    1992-01-01

    Mechanical forces play an important role in the differentiation, growth, and remodeling of skeletal tissues. An increase in the normal loading pattern of the skeleton leads to an increase in bone mass. An overall decrease in the functional load exerted on the skeleton produces mineral loss and osteoporosis. However, the responses of the skeletal tissue cells to various loading conditions are still largely unresolved, as is the mechanism of the cellular response to changed mechanical environment. Using an in vitro approach, we hope to avoid some problems encountered in the use of in vivo animal and man models, which have been extensively used in the past. In a number of experiments we have demonstrated that 16 and 17 day old fetal mouse long bone rudiments (metatarsalia), cultured in a liquid culture medium, are very suitable to study mineralization and resorption, respectively. We have also demonstrated that under hydrostatic compression, mineralization is increased while resorption is decreased. Culture of long bone rudiments under noncompressed control conditions can be regarded as a situation of partial unloading, showing some phenomena of a disuse situation. Under microgravity conditions, responses of osteoblasts and chondrocytes (involved in mineralization) and osteoclasts (involved in mineral resorption), to culture with and without compression, may be much more outspoken. This will have advantages for the study and the interpretation of the role of cellular events in the process of mineralization and resorption of developing skeletal tissues under various loading conditions. The BONES Experiment is carried out in four type I/O and four type I/E containers. Various aspects of the investigation are discussed.

  10. Phytoestrogens directly inhibit TNF-α-induced bone resorption in RAW264.7 cells by suppressing c-fos-induced NFATc1 expression.

    Science.gov (United States)

    Karieb, Sahar; Fox, Simon W

    2011-02-01

    TNF-α-induced osteoclastogenesis is central to post-menopausal and inflammatory bone loss, however, the effect of phytoestrogens on TNF-α-induced bone resorption has not been studied. The phytoestrogens genistein, daidzein, and coumestrol directly suppressed TNF-α-induced osteoclastogenesis and bone resorption. TRAP positive osteoclast formation and resorption area were significantly reduced by genistein (10(-7)  M), daidzein (10(-5)  M), and coumestrol (10(-7)  M), which was prevented by the estrogen antagonist ICI 182,780. TRAP expression in mature TNF-α-induced osteoclasts was also significantly reduced by these phytoestrogen concentrations. In addition, in the presence of ICI 182,780 genistein and coumestrol (10(-5) -10(-6)  M) augmented TNF-α-induced osteoclast formation and resorption. However, this effect was not observed in the absence of estrogen antagonist indicating that genistein's and coumestrol's ER-dependent anti-osteoclastic action normally negates this pro-osteoclastic effect. To determine the mechanism mediating the anti-osteoclastic action we examined the effect of genistein, coumestrol, and daidzein on caspase 3/7 activity, cell viability and expression of key genes regulating osteoclast differentiation and fusion. While anti-osteoclastic phytoestrogen concentrations had no effect on caspase 3/7 activity or cell viability they did significantly reduce TNF-α-induced c-fos and NFATc1 expression in an ER dependent manner and also inhibited NFATc1 nuclear translocation. Significant decreases in NFκB and DC-STAMP levels were also noted. Interestingly, constitutive c-fos expression prevented the anti-osteoclastic action of phytoestrogens on differentiation, resorption and NFATc1. This suggests that phytoestrogens suppress TNF-α-induced osteoclastogenesis via inhibition of c-fos-dependent NFATc1 expression. Our data provides further evidence that phytoestrogens have a potential role in the treatment of post-menopausal and inflammatory

  11. Polyphosphate-mediated inhibition of tartrate-resistant acid phosphatase and suppression of bone resorption of osteoclasts.

    Directory of Open Access Journals (Sweden)

    Kana Harada

    Full Text Available Inorganic polyphosphate (poly(P has recently been found to play an important role in bone formation. In this study, we found that tartrate-resistant acid phosphatase (TRAP, which is abundantly expressed in osteoclasts, has polyphosphatase activity that degrades poly(P and yields Pi as well as shorter poly(P chains. Since the TRAP protein that coprecipitated with anti-TRAP monoclonal antibodies exhibited both polyphosphatase and the original phosphatase activity, poly(P degradation activity is dependent on TRAP and not on other contaminating enzymes. The ferrous chelator α, α'-bipyridyl, which inhibits the TRAP-mediated production of reactive oxygen species (ROS, had no effect on such poly(P degradation, suggesting that the degradation is not dependent on ROS. In addition, shorter chain length poly(P molecules were better substrates than longer chains for TRAP, and poly(P inhibited the phosphatase activity of TRAP depending on its chain length. The IC50 of poly(P against the original phosphatase activity of TRAP was 9.8 µM with an average chain length more than 300 phosphate residues, whereas the IC50 of poly(P with a shorter average chain length of 15 phosphate residues was 8.3 mM. Finally, the pit formation activity of cultured rat osteoclasts differentiated by RANKL and M-CSF were markedly inhibited by poly(P, while no obvious decrease in cell number or differentiation efficiency was observed for poly(P. In particular, the inhibition of pit formation by long chain poly(P with 300 phosphate residues was stronger than that of shorter chain poly(P. Thus, poly(P may play an important regulatory role in osteoclastic bone resorption by inhibiting TRAP activity, which is dependent on its chain length.

  12. Human calcium metabolism including bone resorption measured with {sup 41}Ca tracer

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, S.P.H.T. [Lawrence Livermore National Lab., CA (United States); King, J.C. [California Univ., Berkeley, CA (United States). Dept. of Nutritional Science; Vieira, N.E. [National Inst. of Child Health and Human Development, Bethesda, MD (United States); Woodhouse, L.R. [California Univ., Berkeley, CA (United States). Dept. of Nutritional Science; Yergey, A.L. [National Inst. of Child Health and Human Development, Bethesda, MD (United States)

    1996-08-01

    Accelerator mass spectrometry is so sensitive to small quantities of {sup 41}Ca that it might be used as a tracer in the study of human calcium kinetics to generate unique kinds of data. In contrast with the use of other Ca isotopic tracers, {sup 41}Ca tracer can be so administered that the tracer movements between the various body pools achieve a quasi steady state. Resorbing bone may thus be directly measured. We have tested such a protocol against a conventional stable isotope experiment with good agreement.

  13. DNA aptamer beacon assay for C-telopeptide and handheld fluorometer to monitor bone resorption.

    Science.gov (United States)

    Bruno, John Gordon; Carrillo, Maria P; Phillips, Taylor; Hanson, Douglas; Bohmann, Jonathan A

    2011-09-01

    A novel DNA aptamer beacon is described for quantification of a 26-amino acid C-telopeptide (CTx) of human type I bone collagen. One aptamer sequence and its reverse complement dominated the aptamer pool (31.6% of sequenced clones). Secondary structures of these aptamers were examined for potential binding pockets. Three-dimensional computer models which analyzed docking topologies and binding energies were in agreement with empirical fluorescence experiments used to select one candidate loop for beacon assay development. All loop structures from the aptamer finalists were end-labeled with TYE 665 and Iowa Black quencher for comparison of beacon fluorescence levels as a function of CTx concentration. The optimal beacon, designated CTx 2R-2h yielded a low ng/ml limit of detection using a commercially available handheld fluorometer. The CTx aptamer beacon bound full-length 26-amino acid CTx peptide, but not a shorter 8-amino acid segment of CTx peptide which is a common target for commercial CTx ELISA kits. The prototype assay was shown to detect CTx peptide from human urine after creatinine and urea were removed by size-exclusion chromatography to prevent nonspecific denaturing of the aptamer beacon. This work demonstrates the potential of aptamer beacons to be utilized for rapid and sensitive bone health monitoring in a handheld or point-of-care format.

  14. Obesity induced by high dietary fat leads to increased bone resorption marker, TRAP, and decreased bone mass in mice

    Science.gov (United States)

    Obesity, which is growing in prevalence, is a risk factor for such chronic health disorders as diabetes and cardiovascular diseases. However, it is thought to be a protective factor for osteoporosis and bone fractures in humans. Accumulating data in humans suggest that fat mass has a negative effect...

  15. Early changes in bone density, microarchitecture, bone resorption, and inflammation predict the clinical outcome 12 weeks after conservatively treated distal radius fractures: an exploratory study.

    Science.gov (United States)

    Meyer, Ursina; de Jong, Joost J; Bours, Sandrine G P; Keszei, András P; Arts, Jacobus J; Brink, Peter R G; Menheere, Paul; van Geel, Tineke A C M; van Rietbergen, Bert; van den Bergh, Joop P W; Geusens, Piet P; Willems, Paul C

    2014-09-01

    Fracture healing is an active process with early changes in bone and inflammation. We performed an exploratory study evaluating the association between early changes in densitometric, structural, biomechanical, and biochemical bone parameters during the first weeks of fracture healing and wrist-specific pain and disability at 12 weeks in postmenopausal women with a conservatively treated distal radius fracture. Eighteen patients (aged 64 ± 8 years) were evaluated at 1 to 2 and 3 to 4 weeks postfracture, using high-resolution peripheral quantitative computed tomography (HR-pQCT), micro-finite element analysis, serum procollagen type-I N-terminal propeptide (P1NP), carboxy-terminal telopeptide of type I collagen (ICTP), and high-sensitive C-reactive protein (hsCRP). After 12 weeks, patients rated their pain and disability using Patient Rated Wrist Evaluation (PRWE) questionnaire. Additionally, Quick Disability of the Arm Shoulder and Hand (QuickDASH) questionnaire and active wrist range of motion was evaluated. Linear regression models were used to study the relationship between changes in bone parameters and in hsCRP from visit 1 to 2 and PRWE score after 12 weeks. A lower PRWE outcome, indicating better outcome, was significantly related to an early increase in trabecular bone mineral density (BMD) (β -0.96 [95% CI -1.75 to -0.16], R(2)  = 0.37), in torsional stiffness (-0.14 [-0.28 to -0.004], R(2)  = 0.31), and to an early decrease in trabecular separation (209 [15 to 402], R(2)  = 0.33) and in ICTP (12.1 [0.0 to 24.1], R(2)  = 0.34). Similar results were found for QuickDASH. Higher total dorsal and palmar flexion range of motion was significantly related to early increase in hsCRP (9.62 [3.90 to 15.34], R(2)  = 0.52). This exploratory study indicates that the assessment of early changes in trabecular BMD, trabecular separation, calculated torsional stiffness, bone resorption marker ICTP, and hsCRP after a distal radius fracture provides

  16. The experiment in rat model with alendronate inhibiting abnormal alve olar bone resorption%Alendronate阻止牙槽骨骨吸收的实验研究

    Institute of Scientific and Technical Information of China (English)

    王晓敏; 杨宗萍; 于世凤

    2001-01-01

    Objective.Osteoporosis and periodontal disease animal models were used to evaluate the anti-resorption effect of alendr onate on bone.Methods.To establish osteoporosis and alveo lar bone resorption animal models.The experimental groups (ovariectomized dental ligature group and simple dental ligature group) were given alendronate in 0. 5mg/kg BW by subcutaneous injection after six weeks of ovariectomy and dental ligature,three times a week for 6 weeks.All the animals were sacrifised 12 weeks after the operation.The blood samples were collected for determination of bioch emical indexes.The left femora and jaw bone were processed for histomorphometry. The right femora and mendibles were prepared for determination of bone density and bone biodynamics.Results.As compared with the control groups (without alendronate),the values of experimental groups (with alendronate ) were all significantly improved on bone density and bone anti-curve power.The alkaline phosphatase,calcium in serum of ovariectomy groups (without alendronate ) were obviously increased.In the alendronate group,however,these indexes werec lose to normal levels.In histomorphometry,there were little inflammation in gingiva and less level alveolar bone resorption in the experimental groups;but there was obvious gingivitis and level alveolar bone resorption in the control groups .Conclusion.Alendronate can effectively treat osteoporosis,increase bone volume and prevent bone lose in ovariectomized female rats and inhibit pathological alveolar bone resorption.%目的 评价双膦酸盐Alendronate抑制牙槽骨骨吸收的作用。方法 建立骨质疏松及牙槽骨吸收动物模型,建模术后六周,给实验组皮下注射Alendronate每周3次,共6周;用血生化指标骨生物力学、骨密度测量、组织形态学等方法进行药效评价。结果 股骨骨密度对照 组与用药组相比明显降低(P<0.01);血清碱性磷酸酶对照组与用药组相比明显升

  17. Further significant effects of eldecalcitol on bone resorption markers and bone mineral density in postmenopausal osteoporosis patients having undergone long-term bisphosphonate treatment.

    Science.gov (United States)

    Iba, Kousuke; Sonoda, Tomoko; Takada, Junichi; Dohke, Takayuki; Yamashita, Toshihiko

    2017-03-01

    We investigated whether eldecalcitol has further significant effects on bone metabolic markers and bone mineral density (BMD) in osteoporosis patients having undergone long-term bisphosphonate treatment. Eldecalcitol treatment was initiated in 48 postmenopausal osteoporosis patients who had undergone bisphosphonate treatment with or without alfacalcidol treatment for more than 2 years (average period 6.3 years). Age, height, weight, total muscle volume, total fat volume, estimated glomerular filtration rate, and BMD at the lumbar spine, total hip, and distal third of the radius were measured as background data for each patient. Serum alkaline phosphatase, tartrate-resistant acid phosphatase 5b, calcium, and phosphate levels were measured at the baseline and 3 and 12 months after the initiation of eldecalcitol treatment, and BMD was measured at the baseline and 12 months after the initiation of eldecalcitol treatment. Tartrate-resistant acid phosphatase 5b level was significantly decreased at 3 and 12 months after the initiation of eldecalcitol treatment in comparison with the baseline level. There were no significant changes in alkaline phosphatase, calcium, or phosphate levels in comparison with the baseline levels. In addition, the lumbar spine BMD at 12 months after the initiation of treatment was significantly increased in comparison with the baseline level, although no significant changes in BMD at the total hip and distal third of the radius were observed. Eldecalcitol demonstrated significant effects in additionally decreasing the level of the bone resorption marker tartrate-resistant acid phosphatase 5b and increasing BMD at the lumbar spine, even in osteoporosis patients having undergone long-term bisphosphonate treatment.

  18. Root resorption

    DEFF Research Database (Denmark)

    Kjaer, Inger

    2014-01-01

    Introduction: This paper summarizes the different conditions, which have a well-known influence on the resorption of tooth roots, exemplified by trauma and orthodontic treatment. The concept of the paper is to summarize and explain symptoms and signs of importance for avoiding resorption during...... orthodontic treatment. The Hypothesis: The hypothesis in this paper is that three different tissue layers covering the root in the so-called periroot sheet can explain signs and symptoms of importance for avoiding root resorption during orthodontic treatment. These different tissue layers are; outermost...... processes provoked by trauma and orthodontic pressure. Inflammatory reactions are followed by resorptive processes in the periroot sheet and along the root surface. Evaluation of the Hypothesis: Different morphologies in the dentition are signs of abnormal epithelium or an abnormal mesodermal layer. It has...

  19. Higher bone resorption excretion in South Asian women vs. White Caucasians and increased bone loss with higher seasonal cycling of vitamin D: Results from the D-FINES cohort study.

    Science.gov (United States)

    Darling, A L; Hart, K H; Gossiel, F; Robertson, F; Hunt, J; Hill, T R; Johnsen, S; Berry, J L; Eastell, R; Vieth, R; Lanham-New, S A

    2017-03-07

    Few data exist on bone turnover in South Asian women and it is not well elucidated as to whether Western dwelling South Asian women have different bone resorption levels to that of women from European ethnic backgrounds. This study assessed bone resorption levels in UK dwelling South Asian and Caucasian women as well as evaluating whether seasonal variation in 25-hydroxyvitamin D [25(OH)D] is associated with bone resorption in either ethnic group. Data for seasonal measures of urinary N-telopeptide of collagen (uNTX) and serum 25(OH)D were analysed from n=373 women (four groups; South Asian postmenopausal n=44, South Asian premenopausal n=50, Caucasian postmenopausal n=144, Caucasian premenopausal n=135) (mean (±SD) age 48 (14) years; age range 18-79years) who participated in the longitudinal D-FINES (Diet, Food Intake, Nutrition and Exposure to the Sun in Southern England) cohort study (2006-2007). A mixed between-within subjects ANOVA (n=192) showed a between subjects effect of the four groups (PD was predictive of uNTX, with estimate (SD)=0.213 (0.015) and 95% CI (0.182, 0.245; PD, adjusted for overall 25(OH)D concentration, showed increased levels of uNTX. Although the effect size was smaller than for the amplitude/mesor ratio, the mesor for 25(OH)D concentration was also predictive of uNTX, with estimate (SD)=-0.035 (0.004), and 95% CI (-0.043, -0.028; PD concentration showed an increased bone resorption, an association which was larger than that of the 25(OH)D yearly average, suggesting it may be as important clinically to ensure a stable and steady 25(OH)D concentration, as well as one that is high enough to be optimal for bone health.

  20. A comparative study of the effects of daily minodronate and weekly alendronate on upper gastrointestinal symptoms, bone resorption, and back pain in postmenopausal osteoporosis patients.

    Science.gov (United States)

    Yoshioka, Toru; Okimoto, Nobukazu; Okamoto, Ken; Sakai, Akinori

    2013-03-01

    The purpose of the present study was to precisely compare both the efficacy and abdominal symptom-related quality of life after treatment with daily minodronate and weekly alendronate in patients with primary postmenopausal osteoporosis. The efficacy of the two drugs was assessed based on improvements in a bone turnover marker, back pain, and gastrointestinal symptoms that impair quality of life, which was assessed using the Izumo scale questionnaire. In the minodronate group, there were no significant changes during the treatment period in the specific scores for heartburn, epigastralgia and epigastric fullness, whereas all of the scores were significantly elevated at some time point after drug administration in the alendronate group. Urinary N-telopeptide of type I collagen (uNTX), a bone resorption marker, and bone-specific alkaline phosphatase, a bone formation marker, significantly decreased in both groups, but decreases in uNTX in the minodronate group was observed significantly earlier compared with those in the alendronate group. The back pain scores, which were obtained using a visual analog scale, were significantly reduced in both groups. However, analgesic effects were detected earlier in the minodronate group. In conclusion, compared with weekly alendronate, daily minodronate improved bone turnover and back pain more promptly without causing upper gastrointestinal symptoms.

  1. Systemic effects of fluoxetine on the amount of tooth movement, root resorption, and alveolar bone remodeling during orthodontic force application in rat

    Directory of Open Access Journals (Sweden)

    Mehdi Rafiei

    2015-01-01

    Full Text Available Background: Antidepressant drugs such as fluoxetine are of the most commonly used drugs among the public. These drugs may impact the regulation of bone cell functioning, and thus affect orthodontic tooth movement. The aim of this study was to determine the effect of fluoxetine on tooth movements during orthodontic treatment in rats. Materials and Methods: In this study, 30 male rats were randomly assigned into two groups and injected with fluoxetine 10 mg/kg (experimental group and normal saline (control group for a period of 1-month intraperitoneally 5 times/week. Then, the rats were anesthetized and a nickel-titanium closed-coil spring was placed between the left maxillary first molar and left maxillary central incisors of all samples, and then fluoxetine (experimental group and normal saline (control group were injected for another 3 weeks by the same method. After measuring tooth movements, rats were sacrificed, and histomorphometric analyses were conducted and the obtained data were statistically analyzed using independent t-test and the significance was set at 0.05. Results: Following the fluoxetine injection, the mean amount of tooth movements in the experimental group was reduced compared to the control group, which was not statistically significant (P = 0.14. There was no significant difference between the two groups regarding bone apposition rate (P = 0.83, external root resorption rate (P = 0.1, and mean number of root resorption lacunae (P = 0.16. Conclusion: Within the limitations of this study, systemic use of fluoxetine may cause insignificant reduction of tooth movement rate in rats; however, this subject needs more evaluations.

  2. 阿仑膦酸钠与雷洛昔芬对牙槽骨吸收的影响*%Alendronate and raloxifene affect alveolar bone resorption

    Institute of Scientific and Technical Information of China (English)

    陈锦波; 刘铁玉; 阎美凤; 曲晓娟

    2013-01-01

      背景:研究证明阿仑膦酸钠与雷洛昔芬对骨质疏松有抑制作用。目的:建立实验性大鼠骨质疏松及牙槽骨吸收模型,评价阿仑膦酸钠与雷洛昔芬对骨吸收的防治作用。方法:56只雌性 SD 大鼠建立骨质疏松及牙槽骨吸收的动物模型,实验动物分组:①去势+结扎组和单纯结扎组又分别分为3个亚组:阿仑膦酸钠组、雷洛昔芬组和非用药组。②单纯去势非用药组。③假手术组做空白对照。建模手术后第5日开始灌胃给药,1次/d,治疗3个月。用血生化指标、骨密度测量及组织形态学方法进行药效评价。结果与结论:阿仑膦酸钠治疗组较雷洛昔芬组有更强的降低去势组碱性磷酸酶和血钙的作用;提高去势组骨密度。结果证实阿仑膦酸钠与雷洛昔芬均能减少骨质丢失,从而可以防止骨质疏松及病理性牙槽骨骨吸收,且阿仑膦酸钠作用较好。%BACKGROUND: Studies have shown that alendronate and raloxifene can suppress osteoporosis. OBJECTIVE: To evaluate the anti-osteoporosis effect of alendronate and raloxifene in rat models of osteoporosis and alveolar bone resorption. METHODS: Total y 56 female Sprague-Dawley rats were enrol ed to establish animal models of osteoporosis and alveolar bone resorption. Ovariectomized+ligation group and ligation group were respectively divided into three subgroups: alendronate, raloxifene and non-drug groups. Ovariectomized group and sham operation group (blank control) were set. Intragastric administration was performed at 5 days after modeling, once a day, total y for 3 months. Blood biochemical markers, bone mineral density measurement and histomorphological method were done for evaluation of drug effectiveness. RESULTS AND CONCLUSION: As compared with the raloxifene groups, alendronate groups could significantly reduce alkaline phosphatase and serum calcium levels and promote bone mineral density in the

  3. Transforming growth factor-β synthesized by stromal cells and cancer cells participates in bone resorption induced by oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Ryosuke [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Kayamori, Kou [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Oue, Erika [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Sakamoto, Kei [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Harada, Kiyoshi [Department of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Yamaguchi, Akira, E-mail: akira.mpa@tmd.ac.jp [Department of Oral Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan)

    2015-03-20

    Transforming growth factor beta (TGF-β) plays a significant role in the regulation of the tumor microenvironment. To explore the role of TGF-β in oral cancer-induced bone destruction, we investigated the immunohistochemical localization of TGF-β and phosphorylated Smad2 (p-Smad2) in 12 surgical specimens of oral squamous cell carcinoma (OSCC). These studies revealed TGF-β and p-Smad2 expression in cancer cells in all tested cases. Several fibroblasts located between cancer nests and resorbing bone expressed TGF-β in 10 out of 12 cases and p-Smad2 in 11 out of 12 cases. Some osteoclasts also exhibited p ∼ Smad2 expression. The OSCC cell line, HSC3, and the bone marrow-derived fibroblastic cell line, ST2, synthesized substantial levels of TGF-β. Culture media derived from HSC3 cells could stimulate Tgf-β1 mRNA expression in ST2 cells. Recombinant TGF-β1 could stimulate osteoclast formation induced by receptor activator of nuclear factor kappa-B ligand (RANKL) in RAW264 cells. TGF-β1 could upregulate the expression of p-Smad2 in RAW264 cells, and this action was suppressed by the addition of a neutralizing antibody against TGF-β or by SB431542. Transplantation of HSC3 cells onto the calvarial region of athymic mice caused bone destruction, associated with the expression of TGF-β and p-Smad2 in both cancer cells and stromal cells. The bone destruction was substantially inhibited by the administration of SB431542. The present study demonstrated that TGF-β synthesized by both cancer cells and stromal cells participates in the OSCC-induced bone destruction. - Highlights: • Cancer cell, fibroblastic cells, and osteoclasts at bone resorbing area by oral cancer exhibited TGF-β and p-Smad2. • TGF-β1 stimulated osteoclastogenesis induced by RAKL in RAW264 cell. • Xenograft model of oral cancer-induced bone resorption was substantially inhibited by SB431542. • TGF-β synthesized by both cancer cells and stromal cells participates in the OSCC

  4. Loss of functional NADPH oxidase-2 protects against alcohol-induced bone resorption in female p47phox-/- mice

    Science.gov (United States)

    In bone, oxidant signaling through NADPH oxidase (NOX)-derived reactive oxygen species (ROS) is an important stimulus for osteoclast differentiation and activity. We have previously demonstrated that chronic alcohol abuse produces bone loss through NOX-dependent mechanisms. In the current study, s...

  5. Serum Bone Resorption Markers after Parathyroidectomy for Renal Hyperparathyroidism: Correlation Analyses for the Cross-Linked N-telopeptide of Collagen I and Tartrate-Resistant Acid Phosphatase

    Directory of Open Access Journals (Sweden)

    Kuo-Chin Hung

    2012-01-01

    Full Text Available Patients on long-term dialysis may develop secondary hyperparathyroidism (SHPT with increased serum concentrations of bone resorption markers such as the cross-linked N-telopeptide of type I collagen (NTX and type-5b tartrate-resistant acid phosphatase (TRAP. When SHPT proves refractory to treatment, parathyroidectomy (PTX may be needed. Renal patients on maintenance HD who received PTX for refractory SHPT (n=23 or who did not develop refractory SHPT (control subjects; n=25 were followed prospectively for 4 weeks. Serum intact parathyroid hormone (iPTH, NTX, TRAP, and bone alkaline phosphatase (BAP concentrations were measured serially and correlation analyses were performed. iPTH values decreased rapidly and dramatically. BAP values increased progressively with peak increases observed at 2 weeks after surgery. NTX and TRAP values decreased concurrently and progressively through 4 weeks following PTX. A significant correlation between TRAP and NTX values was observed before PTX but not at 4 weeks after PTX. Additionally, the fractional changes in serum TRAP were larger than those in serum NTX at all times examined after PTX. Serum iPTH, TRAP, and NTX values declined rapidly following PTX for SHPT. Serum TRAP values declined to greater degrees than serum NTX values throughout the 4-week period following PTX.

  6. Enhancement of Osteoclastic Bone Resorption and Suppression of Osteoblastic Bone Formation in Response to Reduced Mechanical Stress Do Not Occur in the Absence of Osteopontin

    OpenAIRE

    Ishijima, Muneaki; Rittling, Susan R.; Yamashita, Teruhito; Tsuji, Kunikazu; Kurosawa, Hisashi; Nifuji, Akira; Denhardt, David T.; Noda, Masaki

    2001-01-01

    Reduced mechanical stress to bone in bedridden patients and astronauts leads to bone loss and increase in fracture risk which is one of the major medical and health issues in modern aging society and space medicine. However, no molecule involved in the mechanisms underlying this phenomenon has been identified to date. Osteopontin (OPN) is one of the major noncollagenous proteins in bone matrix, but its function in mediating physical-force effects on bone in vivo has not been known. To investi...

  7. BEGO种植体不同种植深度的骨吸收的对比研究%Comparative study on bone resorption of different planting depths of BEGO implant

    Institute of Scientific and Technical Information of China (English)

    冯建国; 李慧; 张春梅

    2016-01-01

    目的:本项目通过测定BEGO种植体不同种植深度的骨吸收的长度,探讨BEGO种植体不同种植深度的骨吸收的程度。方法选取于医院就诊并植入BEGO种植体的120例患者,于术前拍口腔曲面断层片,测定颌骨高度,确定种植的深度,按骨面上1mm、骨面平齐、骨下1mm分为a、b、c三组,术后立即、3个月、6个月、1年、1.5年拍曲面断层片,测定种植体尖部到牙槽骨平面的距离并记录数据进行对比分析。结果经研究表明种植体的种植深度为骨面上1mm骨吸收程度较小、骨面平齐骨吸收程度最小、骨下1mm骨吸收程度较大。结论 BEGO种植体不同种植深度的骨吸收的程度不同,种植深度与骨面平齐骨吸收程度最小,其次是骨面上1mm,程度较大的是骨面下1mm。%Objective To explore the extent of bone resorption of different planting depths of BEGO implant by measuring the length of bone resorption of different planting depths of BEGO implant. Methods 120 patients implanted BEGO implant cured in the hospital were selected.They were treated with preoperative oral shoot panoramic radiographs,measuring the height of the jaw to determine the depth of planting.According to the bone surface 1mm, facial flush,lower bone 1mm, they were divided into group a,group b,and group c.They were filmed panoramic radiographs immediately after operation,3 months,6 months,1 year,1.5 years to measure tip of the implant from the plane to the alveolar bone.And the recorded data were analyzed. Results The extent of planting depth for implant bone resorption surface 1mm was smaller,the minimum degree of bone resorption was flush, and the extent of lower bone resorption 1mm was larger. Conclusion The extent of bone resorption of different planting depths of BEGO implant is different.The planting depth was flush with the bone resorption minimum level,followed by the bone surface 1mm, and the larger is the extent of the bone

  8. Pathogenetic analysis and treatment of bone resorption after chin augmentation with prostheses%假体隆颏术后骨吸收的原因分析及治疗

    Institute of Scientific and Technical Information of China (English)

    唐晓军; 张智勇; 石蕾; 尹琳; 刘伟

    2014-01-01

    Objective To analyze and discuss the possible reasons of the bone resorption beneath the prostheses after chin augmentation.Methods Twelve patients were admitted to our department for further correction after chin augmentation with materials.The bone resorption was observed through the clinical research and X-ray examination.Results All the patients were underwent the removal of the materials,genioplasty was performed in 8 patients,and two patients were treated by chin augmentation with polyethylene.All the patients were satisfied with their facial contouring.Mild bone resorption was found in seven patients (depth of bone resorption ≤2 mm),in which five patients were used with silicone materials,two patients were performed with expanded polytetrafluoroethylene implants.Moderate bone resorption was seen in three cases.All of them were used with silicone implants (2 mm < depth of bone resorption ≤4 mm).Severe bone resorption happened in two patients (depth of bone resorption >4 mm).One was used with silicone implant,and the other one was carried out with expanded polytetrafluoroethylene implant.Conclusions The imbalance among mentalis muscle,materials and underlying bone might be one of the key reasons.Thus for mild and moderate microgenia cases,chin augmentation with material is suitable,while long-term fellow-up study is necessary.But for the cases of severe mirogenia or microgenia and micrognathia with dentofacial deformity or mentalis muscle hyperactivity,genioplasty might be performed as well to correct their deformities.%目的 探讨假体隆颏术后颏部骨吸收的可能原因及治疗.方法 分析假体隆颏术后因骨吸收进一步治疗患者12例,通过临床手术所见和放射学检查结果,观察局部颏骨吸收情况.结果 发生轻度或无骨吸收者7例骨吸收(≤2 mm),其中硅橡胶假体5例,膨体聚四氟乙烯假体2例.发生中度骨吸收者3例(骨吸收>2 mm,而≤4 mm),均为硅橡胶

  9. Alterations in osteoclast function and phenotype induced by different inhibitors of bone resorption--implications for osteoclast quality

    DEFF Research Database (Denmark)

    Neutzsky-Wulff, Anita V; Sørensen, Mette Guldmann; Kocijancic, Dino;

    2010-01-01

    Normal osteoclasts resorb bone by secretion of acid and proteases. Recent studies of patients with loss of function mutations affecting either of these processes have indicated a divergence in osteoclastic phenotypes. These difference in osteoclast phenotypes may directly or indirectly have secon...

  10. Feeding blueberry diets to young rats dose-dependently inhibits bone resorption through suppression of rankl in stromal cells

    Science.gov (United States)

    Previous studies have demonstrated that weanling rats fed AIN-93G semi-purified diets supplemented with 10% whole blueberry (BB) powder for two weeks beginning on postnatal day 21 (PND21) significantly increased bone formation at PND35. However, the minimal level of dietary BB needed to produce thes...

  11. Topical HPMC/S-Nitrosoglutathione Solution Decreases Inflammation and Bone Resorption in Experimental Periodontal Disease in Rats.

    Directory of Open Access Journals (Sweden)

    Conceição S Martins

    Full Text Available S-nitrosoglutathione (GSNO is a nitric oxide (NO donor, which exerts antioxidant, anti-inflammatory, and microbicidal actions. Intragingival application of GSNO was already shown to decrease alveolar bone loss, inflammation and oxidative stress in an experimental periodontal disease (EPD model. In the present study, we evaluated the potential therapeutic effect of topical applications of hydroxypropylmethylcellulose (HPMC/GSNO solutions on EPD in Wistar rats. EPD was induced by placing a sterilized nylon (3.0 thread ligature around the cervix of the second left upper molar of the animals, which received topical applications of a HPMC solutions containing GSNO 2 or 10 mM or vehicle (HPMC solution, 1 h prior to the placement of the ligature and then twice daily until sacrifice on day 11. Treatment with HPMC/GSNO 10 mM solution significantly reduced alveolar bone loss, oxidative stress and TNF-α e IL-1β levels in the surrounding gingival tissue, and led to a decreased transcription of RANK and TNF-α genes and elevated bone alkaline phosphatase, compared to the HPMC group. In conclusion, topical application of HPMC/GSNO solution is a potential treatment to reduce inflammation and bone loss in periodontal disease.

  12. Topical HPMC/S-Nitrosoglutathione Solution Decreases Inflammation and Bone Resorption in Experimental Periodontal Disease in Rats

    Science.gov (United States)

    Martins, Conceição S.; Leitão, Renata F. C.; Costa, Deiziane V. S.; Melo, Iracema M.; Santos, Glaylton S.; Lima, Vilma; Baldim, Victor; Wong, Deysi V. T.; Bonfim, Luana E.; Melo, Cíntia B.; Brito, Gerly A. C.

    2016-01-01

    S-nitrosoglutathione (GSNO) is a nitric oxide (NO) donor, which exerts antioxidant, anti-inflammatory, and microbicidal actions. Intragingival application of GSNO was already shown to decrease alveolar bone loss, inflammation and oxidative stress in an experimental periodontal disease (EPD) model. In the present study, we evaluated the potential therapeutic effect of topical applications of hydroxypropylmethylcellulose (HPMC)/GSNO solutions on EPD in Wistar rats. EPD was induced by placing a sterilized nylon (3.0) thread ligature around the cervix of the second left upper molar of the animals, which received topical applications of a HPMC solutions containing GSNO 2 or 10 mM or vehicle (HPMC solution), 1 h prior to the placement of the ligature and then twice daily until sacrifice on day 11. Treatment with HPMC/GSNO 10 mM solution significantly reduced alveolar bone loss, oxidative stress and TNF-α e IL-1β levels in the surrounding gingival tissue, and led to a decreased transcription of RANK and TNF-α genes and elevated bone alkaline phosphatase, compared to the HPMC group. In conclusion, topical application of HPMC/GSNO solution is a potential treatment to reduce inflammation and bone loss in periodontal disease. PMID:27116554

  13. Progression of cartilage degradation, bone resorption and pain in rat temporomandibular joint osteoarthritis induced by injection of iodoacetate.

    Directory of Open Access Journals (Sweden)

    Xue-Dong Wang

    Full Text Available BACKGROUND: Osteoarthritis (OA is an important subtype of temporomandibular disorders. A simple and reproducible animal model that mimics the histopathologic changes, both in the cartilage and subchondral bone, and clinical symptoms of temporomandibular joint osteoarthritis (TMJOA would help in our understanding of its process and underlying mechanism. OBJECTIVE: To explore whether injection of monosodium iodoacetate (MIA into the upper compartment of rat TMJ could induce OA-like lesions. METHODS: Female rats were injected with varied doses of MIA into the upper compartment and observed for up to 12 weeks. Histologic, radiographic, behavioral, and molecular changes in the TMJ were evaluated by light and electron microscopy, MicroCT scanning, head withdrawal threshold test, real-time PCR, immunohistochemistry, and TUNEL assay. RESULTS: The intermediate zone of the disc loosened by 1 day post-MIA injection and thinned thereafter. Injection of an MIA dose of 0.5 mg or higher induced typical OA-like lesions in the TMJ within 4 weeks. Condylar destruction presented in a time-dependent manner, including chondrocyte apoptosis in the early stages, subsequent cartilage matrix disorganization and subchondral bone erosion, fibrosis, subchondral bone sclerosis, and osteophyte formation in the late stages. Nociceptive responses increased in the early stages, corresponding to severe synovitis. Furthermore, chondrocyte apoptosis and an imbalance between anabolism and catabolism of cartilage and subchondral bone might account for the condylar destruction. CONCLUSIONS: Multi-level data demonstrated a reliable and convenient rat model of TMJOA could be induced by MIA injection into the upper compartment. The model might facilitate TMJOA related researches.

  14. Novel antioxidative nanotherapeutics in a rat periodontitis model: Reactive oxygen species scavenging by redox injectable gel suppresses alveolar bone resorption.

    Science.gov (United States)

    Saita, Makiko; Kaneko, Junya; Sato, Takenori; Takahashi, Shun-suke; Wada-Takahashi, Satoko; Kawamata, Ryota; Sakurai, Takashi; Lee, Masaichi-Chang-il; Hamada, Nobushiro; Kimoto, Katsuhiko; Nagasaki, Yukio

    2016-01-01

    The excessive production of reactive oxygen species (ROS) has been implicated in a variety of disorders, but to date, ROS scavengers have not been widely used for local treatment of inflammation, because they are rapidly eliminated from the inflamed site. We have designed a novel redox injectable gel (RIG) that is formed at 37 °C after disintegration of nano-assembled flower micelles allowing nitroxide radicals to act locally as specific ROS scavengers for the treatment of periodontitis. In the present study, we have confirmed retention of the RIG in the periodontal region, along with its antioxidant-related anti-inflammatory effects, and we have subsequently evaluated the inhibitory effect of the RIG against Porphyromonas gingivalis (P. gingivalis)-induced alveolar bone loss attributed to ROS. Alveolar bone loss was estimated by morphometry, gingival blood flow was measured using laser Doppler flowmetry, and osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase staining. The results show that the RIG can inhibit P. gingivalis-induced bone loss by antioxidant-related anti-inflammatory actions, and this suggests that the RIG is a promising novel therapeutic agent for the treatment of P. gingivalis-induced periodontitis.

  15. Retroperitoneal hematoma with bone resorption around the acetabular component after total hip arthroplasty: a case report and review of the literature

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    Uchida Kenzo

    2012-09-01

    Full Text Available Abstract Introduction Vascular complications related to cup-fixating screws penetrating the medial acetabular wall during total hip arthroplasty are not uncommon but rarely are associated with serious adverse events in the late post-operative period. Case presentation We present the case of a 77-year-old Japanese woman who developed progressive extensive bone resorption and large hematoma in the acetabulum 13 years after total hip arthroplasty. On admission to our hospital, she was on oral warfarin (1.5mg/day for atrial fibrillation. About 5 months after the initiation of anticoagulant therapy, she suffered a major fall followed by massive subcutaneous and pelvic girdle bleeding, predominantly on the medial side of the right thigh, but a fracture or damage of total hip arthroplasty was not evident on an emergency orthopedic evaluation. One year after the accident, a routine follow-up examination showed an asymptomatic osteolytic lesion in the acetabulum on the right pelvis, and 2 years later our patient noticed progressive pain in her right hip during walking. A large osteolytic lesion was noted in the right acetabulum on a plain radiograph. On high-resolution computed tomography and magnetic resonance imaging, a huge granulomatous lesion in the acetabulum was suggestive of chronic hematoma in intrapelvic and extrapelvic gluteal regions. A closer computed tomography examination showed that one of the screws used for fixation of the acetabular component in the total hip arthroplasty had penetrated the acetabular bone and had reached the pelvic cavity. Surgery was performed in a single session by means of two approaches: anterior midline transperitoneal address to resect the low-density mass lesion followed by posterolateral acetabular implant re-settlement. Conclusions Though rare, total hip arthroplasty-related late vascular complications could be serious and potentially affect the limb and quality of life.

  16. Effects of a herbal gel containing carvacrol and chalcones on alveolar bone resorption in rats on experimental periodontitis.

    Science.gov (United States)

    Botelho, Marco Antonio; Rao, Vietla Satyanarayana; Montenegro, Danusa; Bandeira, Mary Anne Menezes; Fonseca, Said Gonçalves Cruz; Nogueira, Nadia Accioly Pinto; Ribeiro, Ronaldo Albuquerque; Brito, Gerly Anne Castro

    2008-04-01

    Carvacrol and dimeric chalcones are the respective bioactive components of Lippia sidoides and Myracrodruon urundeuva, popular medicinal plants of Northeastern Brazil with proven antimicrobial and antiinflammatory properties. Periodontal disease is associated with inflammation and microbiological proliferation, thus the study aimed to investigate the effect of a topical gel based on carvacrol and chalcones in the experimental periodontal disease (EPD) in rats. Animals were treated with carvacrol and/or chalcones gel, immediately after EPD induction, three times a day for 11 days. Appropriate controls were included in the study. Animals were weighed daily. They were killed on day 11, the mandibles dissected and alveolar bone loss was measured. The periodontium were examined at histopathology and the neutrophil influx into the gingiva was assayed using myeloperoxidase activity. The bacterial flora were assessed through culture of the gingival tissue. Alveolar bone loss was significantly (p gel, compared with the vehicle and non-treated groups. The treatment with the combined gel reduced tissue lesion at histopathology, decreased myeloperoxidase activity in gingival tissue and inhibited the growth of oral microorganisms as well as the weight loss. Carvacrol and chalcones combination gel has a beneficial effect upon EPD in this model.

  17. Green Tea Modulates Cytokine Expression in the Periodontium and Attenuates Alveolar Bone Resorption in Type 1 Diabetic Rats.

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    Gabriela Gennaro

    Full Text Available Diabetes mellitus comprises a heterogeneous group of disorders with the main feature of hyperglycemia. Chronic hyperglycemia increases the severity of periodontal disease via an exacerbated inflammatory response, activated by advanced glycation end products and their receptor, RAGE. Therefore, anti-inflammatory agents represent potential inhibitors of this pathological interaction. In particular, green tea has been shown to possess anti-inflammatory properties mediated by its polyphenol content.This study investigated the mechanisms by which green tea attenuates the spontaneous onset of diabetes-induced periodontitis.Diabetes was induced in rats via a single intraperitoneal injection of streptozotocin (STZ. Diabetic and control animals were divided into water-treated and green tea-treated subgroups and were analyzed at 15, 30, 60 and 90 days after diabetes induction. Immunohistochemistry was performed to quantitatively evaluate tumor necrosis factor-α (TNF-α, receptor activator of nuclear factor kappa-B ligand (RANKL, osteoprotegerin (OPG, interleukin-10 (IL-10 and runt-related transcription factor 2 (RUNX-2 expression in serial sections of each hemimaxilla. Morphometric measurements of the distance from the cementum-enamel junction (CEJ of the superior distal root of the first molar to the alveolar bone crest (ABC were performed to assess bone loss.Diabetes resulted in significant bone loss and alterations in the number of cells that stained positive for inflammatory mediators. In the diabetic rats treated with green tea, we observed a decreased number of cells expressing RANKL and TNF-α compared with that observed in the diabetic rats treated with water. Additionally, green tea increased the numbers of cells that stained positive for OPG, RUNX-2 and IL-10 in the diabetic rats.Green tea intake reduces expression of the pro-inflammatory cytokine TNF-α and the osteoclastogenic mediator RANKL to normal levels while increasing expression of the

  18. [Calcitonin as an alternative treatment for root resorption].

    Science.gov (United States)

    Pierce, A; Berg, J O; Lindskog, S

    1989-01-01

    Inflammatory root resorption is a common finding following trauma and will cause eventual destruction of the tooth root if left untreated. This study examined the effects of intrapulpal application of calcitonin, a hormone known to inhibit osteoclastic bone resorption, on experimental inflammatory root resorption induced in monkeys. Results were histologically evaluated using a morphometric technique and revealed that calcitonin was an effective medicament for the treatment of inflammatory root resorption. It was concluded that this hormone could be a useful therapeutic adjunct in difficult cases of external root resorption.

  19. Effect of osthol on apoptosis and bone resorption of osteoclasts cultured in vitro%蛇床子素对体外培养破骨细胞骨吸收及细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    明磊国; 王鸣刚; 陈克明; 周建; 韩桂秋; 朱瑞清

    2012-01-01

    This study is to investigate the effect of osthol on osteoclasts' activity, bone resorption as well as apoptosis in vitro, and explore the mechanism of osthol in preventing osteoporosis. Osteoclasts were separated from long-limb bones of new born rabbits, cultured in 24-well plate with glass slices and bone slices, and treated by l×l0-5 mol·L-1 osthol. Osteoclasts were identified by observing live cells with phase contrast microscope, HE staining, TRAP staining and toluidine blue staining of bone resorption pits. The numbers of bone resorption pits were counted as well as the surface area of bone resorption on bone slice. Osteoclasts were stained with acridine orange to detect the cell apoptosis. The ratio of apoptotic osteoclasts was observed under fluorescence microscope. The gene expression of RANKL, OPG, TRAP and p-JNKl/2 protein expression were examined using real time PCR and Western blotting, respectively. Comparing with the control group without osthol, the rates of apoptotic osteoclasts increased obviously and the number and area of bone resorption pits decreased evidently with l×l0-5 mol·L-1 osthol. There is significant difference between control group and experiment group treated by l×l0-5 mol·L-1 osthol. Therefore, the osthol through RANK+RANKL/TRAF6/Mkk/JNK signal pathway inhibits the osteoclasts activity, enhances osteoclasts apoptotic and inhibits the bone resorption.%研究蛇床子素对破骨细胞骨吸收的影响及其分子机制.采用体外分离、培养兔破骨细胞,与盖玻片及骨磨片共同培养,使用1× 10-5 mol·L-1蛇床子素刺激破骨细胞,观察活体细胞并依据HE、TRAP、骨陷窝甲苯胺蓝染色鉴定破骨细胞;进行骨吸收陷窝和面积定量分析,吖啶橙染色统计凋亡细胞;real time PCR及Western blotting法检测相关基因和蛋白.与空白对照组比较,1×10-5 mol·L-1蛇床子素能够明显提高破骨细胞凋亡率并通过抑制RANKL和TRAP等相关基因及JNK1/2磷酸化水

  20. Study on bone resorption of ANKYLOS implant and XIVE implant%骨水平种植体与软组织水平种植体的临床疗效比较

    Institute of Scientific and Technical Information of China (English)

    刘健; 葛自力; 惠建华; 朱丽; 周黎娜

    2012-01-01

    目的 探讨骨水平种植体(ANKYLOS)和软组织水平种植体(XIVE)在种植完成负重后的短期、中长期骨稳定性的差异.方法 采用牙片和曲面断层片观察50例XIVE和68例ANKYLOS单牙种植患者在修复完成后3、6、12个月的植体周围牙槽骨高度的变化,比较骨吸收高度的差异.结果 XIVE种植体在植入后1年内,种植体周围牙槽骨呈进行性吸收,ANKYLOS种植体在植入后1年内,种植体周围牙槽骨有缓慢吸收,吸收速度呈匀速状;两种种植体在不同观察期,骨吸收水平ANKYLOS优于XIVE.结论 在排除了表面处理技术和负重条件等重要影响条件下,在种植体周围骨吸收的环节上,骨水平种植体ANKYLOS要优于软组织水平种植体XIVE.%Objective To explore the short-term, medium-and long-term bone stability difference between bone level implant (ANKYLOS) and soft tissue level implant (XIVE) . Methods Dental films and panoramic radiographs in 50 cases of XIVE and 68 cases of ANKYLOS single dental implant were used for observation of the height changes of the alveolar bones around the implant bones implanted for 3, 6 and 12 months, in single dental implants restration in 50 cases of XIVE and 68 cases of ANKYLOS. The observation was also made for bone resorption with statistical analysis. Results One year after implantation, alveolar bone around the XIVE implant made absorption progressively and alveolar bone a-round the ANKYLOS implant did evenly and slowly; Observation and analysis on two kinds of implants in different observation period were made, the level of bone resorption in ANKYLOS was better in ANKYLOS implant than that in XIVE. Conclusion With exception of the surface treatment technology and impact loading conditions, and other important conditions, in bone resorption areas around the implant, the bone level implant is superior to the soft tissue level implants.

  1. Research progress on mechanisms and regulations of bone resorption in orthodontic tooth movement%正畸牙移动中骨吸收机制及其调控的研究进展

    Institute of Scientific and Technical Information of China (English)

    包幸福

    2012-01-01

    破骨细胞在正畸牙移动压力侧骨吸收过程中发挥着重要的作用,针对破骨细胞分化成熟及其发挥功能的调控研究,能为正畸治疗中控制牙齿移动提供新的思路,同时有助于防治正畸治疗中出现的牙根外吸收等.%Osteoclast is responsible for bone resorption in the compression side of orthodontic tooth movement. Regulations to differentiation and mature of osteoclast may provide new horizons of tooth movement control in orthodontic treatment. At the same time, it is helpful to know the similar mechanisms of root resorption.

  2. 阿仑膦酸钠防治牙槽骨吸收的实验研究%The treatment of osteoporosis and bone resorption of alveoli with alendronate in rat model

    Institute of Scientific and Technical Information of China (English)

    王晓敏; 杨宗萍; 于世凤

    2001-01-01

    目的用骨质疏松及牙槽骨吸收动物模型评价阿仑膦酸盐对骨吸收的防治作用。方法建立骨质疏松及牙槽骨吸收的动物模型,建模手术次日,给实验组皮下注射阿仑膦酸钠液,每周3次,共6周。用血生化指标、骨生物力学、骨密度测量及组织形态学方法进行药效评价。结果股骨密度:对照组(0.123 g/cm2)与实验组(0.151 g/cm2)相比明显降低(P<0.01);血清碱性磷酸酶:对照组(259.63 U/L)与实验组(151.13 U/L)相比明显升高(P<0.01);骨生物力学各项指标,实验组与对照组也有明显差异。组织形态学:实验组牙龈轻度炎症,牙槽嵴顶未见明显吸收;对照组牙龈乳突炎症明显,上皮钉突增生,炎细胞浸润,牙槽嵴顶明显吸收。结论阿仑膦酸钠能减少骨质丢失从而可以防止骨质疏松及病理性牙槽骨骨吸收。%Objective To evaluate the anti-osteoporosis effect of alendronate on bone in rat model. Methods The osteoporosis and alveolar bone resorption animal model were established in rats. The experimental groups were given alendronate in 5 mg/kg BW by subcutaneous injection after first day of ovariectomy and dental ligature, three times a week for 6 weeks. All the animals were sacrifised 12 weeks after the operation. The blood samples were collected for determination of biochemical indices. The left femora and jaw bones were processed for histomorphometry. The right femora and mendibles were prepared for determination of bone density and bone biodynamics. Results As compared with the control groups(without alendronate), the values of experimental groups (with alendronate) were all significantly improved on bone density, bone anti-flexure ability and body weight. The alkaline phosphatase, calcium in serum of ovariectomy groups(without alendronate) were obviously increased. In the experimental group, however, these indices were close to normal levels. In

  3. Antioxidant alpha-lipoic acid inhibits osteoclast differentiation by reducing nuclear factor-kappaB DNA binding and prevents in vivo bone resorption induced by receptor activator of nuclear factor-kappaB ligand and tumor necrosis factor-alpha.

    Science.gov (United States)

    Kim, Hyon Jong; Chang, Eun-Ju; Kim, Hyun-Man; Lee, Seung Bok; Kim, Hyun-Duck; Su Kim, Ghi; Kim, Hong-Hee

    2006-05-01

    The relationship between oxidative stress and bone mineral density or osteoporosis has recently been reported. As bone loss occurring in osteoporosis and inflammatory diseases is primarily due to increases in osteoclast number, reactive oxygen species (ROS) may be relevant to osteoclast differentiation, which requires receptor activator of nuclear factor-kappaB ligand (RANKL). Tumor necrosis factor-alpha (TNF-alpha) frequently present in inflammatory conditions has a profound synergy with RANKL in osteoclastogenesis. In this study, we investigated the effects of alpha-lipoic acid (alpha-LA), a strong antioxidant clinically used for some time, on osteoclast differentiation and bone resorption. At concentrations showing no growth inhibition, alpha-LA potently suppressed osteoclastogenesis from bone marrow-derived precursor cells driven either by a high-dose RANKL alone or by a low-dose RANKL plus TNF-alpha (RANKL/TNF-alpha). alpha-LA abolished ROS elevation by RANKL or RANKL/TNF-alpha and inhibited NF-kappaB activation in osteoclast precursor cells. Specifically, alpha-LA reduced DNA binding of NF-kappaB but did not inhibit IKK activation. Furthermore, alpha-LA greatly suppressed in vivo bone loss induced by RANKL or TNF-alpha in a calvarial remodeling model. Therefore, our data provide evidence that ROS plays an important role in osteoclast differentiation through NF-kappaB regulation and the antioxidant alpha-lipoic acid has a therapeutic potential for bone erosive diseases.

  4. 雌激素对绝经后妇女牙槽骨吸收的影响机制%The mechanisms of estrogen involved in the alveolar bone resorption

    Institute of Scientific and Technical Information of China (English)

    潘央央

    2011-01-01

    Estrogen is involved in the process of alveolar bone resorption. The biological actions may carry out through two pathways: 1)direct action through estrogen receptors on cell membrane; 2)indirect action through cytokines' effects. This paper discussed the mechanisms of estrogen involved in the alveolar bone resorption through the two possible ways mentioned before.%雌激素水平能影响牙槽骨吸收,其生物学效应可能主要通过2种途径实现:1)直接通过细胞表面的雌激素受体介导,主要包括经典的基因组途径和雌激素受体介导的非基因组途径;2)调节细胞因子表达,通过它们的作用调节骨代谢,本文就雌激素作用于牙槽骨影响其代谢的这2种可能途径的研究进展作一综述.

  5. 上颌中切牙种植体的应力改变及骨吸收变化%Cervical Zone of Cortical Bone with the Obvious Resorption of the Bone

    Institute of Scientific and Technical Information of China (English)

    宋涛; 蔡国平; 徐培成

    2011-01-01

    目的:观察上颌中切牙种植体植入方向在与牙冠长轴不同夹角情况下,种植体骨界面应力变化值和最大安全角度的临界值,以此来指导种植前设计.方法:应用有限元法分析不同倾斜角度对种植体骨界面应力峰值影响.结合临床病例,使用X线头影测量分析,测算出患者理想牙冠长轴的位置,以此轴线与种植体长轴的夹角作为倾斜角度分析在不同角度下种植体的骨界面应力变化和中切牙种植病例的周围骨吸收情况.倾斜角0°-20°范围内边缘骨吸收值和种植体骨界面应力值均在正常范围内,适合使用角度基台修复;倾斜角大于20°或25°以上时,应力值有明显升高趋势,种植体唇侧颈部应力集中区骨吸收明显.结论:建议做牙槽骨改建手术,改变种植体植入角度.%Objective:To observe the change of he stress on implant and bone interface and the critical point of the maximum security angle under the condition of different angles of the implants direction and dental crowns long axis of the maxillary central incisor so as to guide the implant designs.Methods: The finite element method was used to analyze the change of the stress on implant and bone interface under different angles of the implants direction.We found the ideal position of the long axis of the maxillary central incisors with combining clinical cases and cephalographs.The stress change of implant and bone interface and the marginal bone loss around implants are both analyzed when the angle between the implant and the ideal location of the incisors changes.Results: When the abutment angulations of the maxillary central incisor were between 0 to 20, the marginal bone resorption and the implant-bone-interface stress were normal.But when the abutment angulations of the maxillary central incisor increased to 20 or 25,the implant stress increases sharply.Peak tensile stresses were focused in labial.Conclusions: It is suggested that the

  6. Research prowess on reduction of bone resorption through alveolar ridge preservation after tooth extraction%应用牙槽窝保存技术减少拔牙后骨吸收的研究进展

    Institute of Scientific and Technical Information of China (English)

    张勇

    2011-01-01

    口腔种植作为一种缺失牙的修复方式已经被临床广泛地接受,然而,成功的种植修复需要有足够的牙槽骨骨量和良好的牙槽嵴外形.患者的牙齿拔除后,骨吸收会造成牙槽嵴体积和外形的变化.若这种变化在临床上较为明显,可以对种植修复或传统修复造成困难.牙槽嵴保存技术则可以使拔牙后的牙槽嵴吸收最小化,可以保持足够的牙槽骨量,从而有助于获得理想的美学和功能修复.本文对牙槽窝保存技术、微创拔牙技术、拔牙后的牙槽窝愈合模式以及骨移植材料和屏障膜的使用作一综述.%Implant therapy has become a widely recognized treatment alternative for replacing missing teeth.While successful implant therapy requires sufficient alveolar bone volume and favorable ridge architecture. After tooth extraction, dimensional changes of the alveolar ridge often occur due to bone resorption. These changes are usually clinically significant and can complicate restorations with implant or conventional prostheses. Preservation of alveolar dimension can minimize residual ridge resorption and can be essential to maintain adequate bone volume, thus be crucial to achieve optimal esthetic and functional prosthodontic results. This article reviewed the literature, presents socket preservation techniques, atraumatic tooth extraction, healing pattern of socket after tooth extraction as well as the use of bone grafting materials and barrier membranes.

  7. Apical External Root Resorption and Repair in Orthodontic Tooth Movement: Biological Events

    Directory of Open Access Journals (Sweden)

    Liviu Feller

    2016-01-01

    Full Text Available Some degree of external root resorption is a frequent, unpredictable, and unavoidable consequence of orthodontic tooth movement mediated by odontoclasts/cementoclasts originating from circulating precursor cells in the periodontal ligament. Its pathogenesis involves mechanical forces initiating complex interactions between signalling pathways activated by various biological agents. Resorption of cementum is regulated by mechanisms similar to those controlling osteoclastogenesis and bone resorption. Following root resorption there is repair by cellular cementum, but factors mediating the transition from resorption to repair are not clear. In this paper we review some of the biological events associated with orthodontically induced external root resorption.

  8. Dental Cone Beam Computed Tomography Analyses of Resorption of Labial Bone in Maxillary Anterior Implant by Bone Splitting Technique%CBCT技术研究前牙区骨劈开术种植修复的骨吸收特点

    Institute of Scientific and Technical Information of China (English)

    王文君; 马敏

    2015-01-01

    目的:采用CBCT技术分析骨劈开手术后种植体唇侧骨板垂直骨吸收特点及与水平向厚度的关系.方法:选取19例上前牙种植患者,共26个种植牙位,牙槽嵴宽度均在3~5 mm之间,采用骨劈开手术联合引导骨组织再生术(GBR)种植Ankylos种植体,患者种植修复完成时和2年后复诊时均拍摄锥形束CT,观察唇侧骨板吸收特点,并根据统计学分析唇侧垂直骨吸收与牙龈退缩的相关性,及与骨板水平向厚度的相关性.结果:种植体唇侧骨板垂直骨吸收与牙龈的退缩有明显的相关性,与唇侧骨板颈部水平向厚度也有相关性.结论:种植治疗时骨劈开技术能够有效增宽牙槽嵴宽度,种植体颈部唇侧骨板水平向厚度是唇侧骨板垂直骨吸收与牙龈退缩的一个重要影响因素.%Objective:To evaluate the vertical bone resorption of labial bone in anterior maxillary implant by bone splitting technique.Methods:19 patients (8 men,11 women) whose ages ranged from 22 to 65 years,were included in this study.The labial-lingual thickness of alveolar was from 3.0 to 5.0mm for everybody,26 Ankylos implants (3.5mm)were placed after splitting the bone immediately and constructed with the operation of guided bone regeneration,CBCT were taken after crown setted immediately and two years later to observe the labial bone resorption.The value of the labial bone resorption and gingival recession were calculated and analysed and the correlation between these changes were detected in SPSS 11.0.Results:Both vertical bone resorption and gingival recession showed a significant negative correlation to cervical width.As expected,vertical bone resorption and gingival recession showed a significant positive correlation.Conclusion:It is suggested that alveolar bone thickness after implant placement in the anterior region could be negatively associated with the level of alveolar bone resorption at the labial aspect as well as gingival recession.

  9. OPG/RANKL/RANK系统参与牙槽骨吸收及重建过程作用初探%Role of OPG/RANKL/RANK system during alveolar bone resorption and remodeling

    Institute of Scientific and Technical Information of China (English)

    陈莉丽; 黄玫; 雷利红; 吴燕岷

    2013-01-01

    目的 初步探讨护骨素OPG、核因子κB受体活化因子配体RANKL、核因子κB活化因子RANK在牙周炎牙槽骨吸收及骨重建过程中的作用.方法 对小鼠单核巨噬细胞白血病细胞株RAW264.7实验组进行体外诱导培养,对照组为完全培养基培养;小鼠成骨样细胞株MC3T3-E1实验组采用前期实验收集的骨吸收上清处理,对照组采用完全培养基培养;以免疫荧光等方法检测细胞OPG、RANKL、RANK的表达.30只8周龄雄性SD大鼠建立实验性牙槽骨吸收模型,研究其吸收重建规律.以免疫组化S-P法检测OPG、RANKL、RANK的表达情况.结果 实验组MC3T3-E细胞经骨吸收上清处理7d后,OPG蛋白平均荧光强度为(29.636±5.652),对照组为(15.568±1.229),表达显著上调(P<0.01);但实验组RANKL蛋白平均荧光强度为(6.806±1.738),对照组为(18.082±2.732),表达被显著抑制(P<0.01),OPG/RANKL比值在上清处理后高于对照组(P<0.05).采用大肠杆菌内毒素E-LPS注射法成功制备大鼠牙槽骨吸收模型.在牙槽骨吸收区域OPG水平较无骨吸收区域有所降低,RANKL的表达则相反.结论 OPG、RANKL、RANK参与了大鼠实验性骨吸收活动;破骨细胞骨吸收上清可能通过改变OPG与RANKL的比值,从而影响骨重建中骨形成与骨吸收的动态平衡.%Objective To investigate the potential role of a system containing osteoprotegerin (OPG) , receptor activator of NF-kB ligand ( RANKL) , and receptor activator of nuclear factor-kappa B ( RANK) , also as, OPG/RANKL/RANK system in the resorption and remodeling mechanisms of alveolar bone. Methods Mouse RAW264. 7 cell line was induced to osteoclasts in vitro, and mouse MC3T3-E1 cell line was treated with bone resorption supernatant. The control cells was cultured with regular medium. The expression levels of OPG, RANKL and RANK in the cells was detected by immunofluorescence assay. Thirty 8-week-old male SD rats were used to establish the

  10. Orchestration of bone remodeling

    NARCIS (Netherlands)

    Moester, Martiene Johanna Catharina

    2014-01-01

    In healthy individuals, a balance exists between bone formation and resorption. Disruption of this balance can lead to higher or lower bone mass, and disease such as osteoporosis. Treatment for osteoporosis generally inhibits bone resorption, but does not rebuild bone to a healthy strength. More kno

  11. Invasive cervical root resorption: Engineering the lost tissue by regeneration

    Directory of Open Access Journals (Sweden)

    Dexton Antony Johns

    2013-01-01

    Full Text Available Invasive cervical resorption (ICR is a localized resorptive process that commences on the surface of the root below the epithelial attachment and the coronal aspect of the supporting alveolar process, namely the zone of the connective tissue attachment′ early diagnosis, elimination of the resorption and restorative management are the keys to a successful outcome. Treatment done was a combined non-surgical root canal therapy, surgical treatment to expose the resorptive defect and the resorptive defect was filled up with reverse sandwich technique and finally the bony defect filled with platelet rich fibrin (PRF, hydroxylapatite and PRF membrane. Significant bone fill was obtained in our case after a 2 year follow-up period. This case report presents a treatment strategy that might improve the healing outcomes for patients with ICR.

  12. Frequency of the external resorptions of root apex

    Directory of Open Access Journals (Sweden)

    Opačić-Galić Vanja

    2004-01-01

    Full Text Available Root resorptions present a significant problem in endodontic therapy of the affected teeth and in dentistry in general. The objective of this study was to analyze, based on epidemiological and statistical research, the frequency of clinical incidence of pathological root resorptions in everyday practice related to localization, type of tooth, age and sex of patients. Radiographie documentation of patients treated from 1997 till 2002 at the Department of Conservative Dentistry and Endodontics, Faculty of Stomatology in Belgrade, was used as baseline for this study. Retroalveolar radiographs of teeth with visible signs of resorptions were singled out from 15654 patients' clinical records used for this study. The external resorptions were shown as radiolucent areas localized on various outer root surfaces, followed by significant or less significant resorption of lamina dura and alveolar bone. Out of all teeth analyzed in this study, 594 (3.79% showed some kind of resorption. The external resorptions were found to be more present in the upper jaw (55.10% and molars (50.30% than in the lower jaw (44.90% and single root teeth (49.70%, but in both cases without significant statistical differences. The most frequent localization of resorptions was root apex (82.44%. In regard to age, the most frequent resorptions were recorded in patients aged between 21 and 30 years (28.40%, and the lowest incidence was found in the youngest population (5.51%. The results also showed that resorptions were more frequent among the female population (59.04% than among the male population (40.96%. Based on these results, we may conclude that the external root resorptions are not a frequent clinical phenomenon. Proper and early diagnostics of such tissue pathology is one of the basic prerequisites for successful endodontic therapy of the affected root.

  13. Influence of Bushenguchiwan on Alveolar Bone Resorption of Rats with Experimental Periodontitis%补肾固齿丸对大鼠实验性牙周炎牙槽骨吸收的影响

    Institute of Scientific and Technical Information of China (English)

    杨恒; 丁一; 文钦

    2012-01-01

    目的 观察补肾固齿丸对大鼠实验性牙周炎牙槽骨吸收的影响,进一步探讨补肾固齿丸对牙周炎的治疗机理.方法 建立大鼠牙周炎模型,给予补肾固齿丸治疗,采用放射免疫法测定血清骨钙蛋白与Ⅰ型胶原交联C端肽浓度,同时采用体式显微镜进行牙槽骨吸收分析,以评价补肾固齿丸对大鼠实验性牙周炎的治疗作用.结果 经过补肾固齿丸治疗30d后,补肾固齿丸高中低剂量组血清中骨钙蛋白与Ⅰ型胶原交联C端肽的浓度均低于牙周炎模型组(P<0.05),同时体式显微镜观察高中低剂量大鼠牙槽骨吸收总值明显低于牙周炎模型组(P<0.05),而三个剂量组之间无显著性差异(P>0.05).结论 补肾固齿丸能改善牙周炎大鼠牙槽骨代谢状况,减少牙槽骨的吸收.%Objective To explore the influence of Bushenguchiwan on alveolar bone resorption of rats with experimental periodontitis, and to discuss the treatment mechanism of Bushenguchiwan. Methods The model of experimental periodontitis of rats were established. Bushenguchi-wan were used to treat experimental periodontitis of rats. The content variation of osteocalcin ( OC1N) and pyridinoline cross-linked carboxy-terminal telopeptide of type 1 collagen ( ICTP) in serum were observed by radioimmunoassay { RIA). Alveolar bone loss was measured aa the distance from the cemento-enamel junction to the alveolar crest. Results After 30 days treatment of Bushenguchiwan with the level of OCN and ICTP in serum was decreased in three treatment groups, compared with model control group (P 0. 05). Conclusion Bushenguehiwan could reduce alveolar bone resorption of rats with experimental periodontitis.

  14. Clinical Observation of Bone Resorption in the Combination of Natural Teeth and Dental Implant%自然牙与种植联合修复体基牙的骨吸收临床观察

    Institute of Scientific and Technical Information of China (English)

    苗美娜

    2016-01-01

    Objective To study the effect of bone resorption of natural teeth and dental implant on abutment.Methods 11 cases of patients with dental dentition defect who need to ifx partial denture were selected as observation group with a total of 11 molar area implant (6 pieces of maxillary, 5 pieces of mandibular). At the same time, 14 cases of patients with molar porcelain tooth that single crown body were selected as control group. Observation group was used about the implant and natural teeth. The mesial and distal bone resorption of implants and natural teeth were compared between two groups after planting load 1, 6, 12 months. The loosening and fracture of the combined retainer and prosthesis were observed.ResultsAt the follow-up of 12 months, the far natural root height of bone resorption in observation group was significantly higher than that in control group (P0.05). The prosthesis loosening and fracture in observation group and control group were occurred.Conclusion Implant and the natural tooth joint retention are the common means to repair teeth, which can effectively solve the problem of bone augmentation and complicated operation rejection patients’ growing demand.%目的:探讨自然牙与种植联合固位对基牙的骨吸收的影响。方法收集11例牙列缺损、要求固定义齿修复患者,共11个磨牙区种植体(上颌6枚,下颌5枚)设置为观察组,选择同时期14例磨牙区烤瓷牙单冠修复体作为对照组。观察组采用种植牙与自然牙联合固位。比较两组观察种植负载1、6、12个月时种植体及自然牙近中、远中骨吸收情况。观察联合固位体及修复体松动和折断情况。结果随访12个月中,观察组自然牙根远中骨吸收高度明显大于对照组自然牙根(P<0.05)。观察组中种植体骨吸收高度与对照组骨吸收高度比较无统计学差异(P>0.05)。联合组固位体和对照组修复体均未出现修复体松动、折断情况。

  15. Anti-bone resorption activity of deer antler aqua-acupunture, the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe (Nokyong) in adjuvant-induced arthritic rats.

    Science.gov (United States)

    Kim, Kyung-Ho; Kim, Kap-Sung; Choi, Byeong-Joon; Chung, Kang-Hyun; Chang, Young-Chae; Lee, Seung-Duk; Park, Kwan-Kyu; Kim, Hyung-Min; Kim, Cheorl-Ho

    2005-01-15

    Effect of deer antler aqua-acupunture (DAA), prepared from the pilose antler of Cervus korean TEMMINCK var. mantchuricus Swinhoe, a traditional immunosuppressive acupuncture, was evaluated to assess the reductions in bone mass, strength, and turnover in adjuvant-induced arthritic rats. For measuring the above parameters, a 20-day dosing experiment was performed using 6-week-old female Lewis rats. Arthritis was induced by injecting the adjuvant into the hind paw of the Lewis rats. The age-dependent increases in the body weight, lumbar bone mineral content and density (BMC and BMD) and compressive strength were disturbed in the arthritic rats. At 10 days, the histomorphometric parameters of bone formation (BFR/BS and BFR/BV) and the serum osteocalcin levels were significantly reduced compared with the baseline controls of Lewis rats. However, the BMC values corrected for body weight did not differ significantly between the arthritic and normal rats, and the bone minerals were not reduced when they were compared with the baseline controls. At 20 days, the parameters of bone minerals and strength of the lumbar body in the arthritic rats, both with and without correction for body weight, were significantly reduced compared with the baseline controls. The trabecular mineralizing surface remained significantly reduced and the osteoclast numbers were increased. DAA at the doses of 10, 20, 50 and 100 microg/kg, administered by Shinsu (B23) acupuncture daily from the start of the experiment, significantly prevented the development of the chronic paw edema at 20 days. The reductions in the parameters such as bone minerals, strength, and trabecular bone formation, and the increase in osteoclast number were alleviated by this DAA. Age-dependent increases in the lumbar height, disturbed by the adjuvant injection, were also maintained. These results indicated that a 20-day-period is necessary to obtain sufficient reductions in the bone mass and strength of the lumbar body

  16. Effects of the natural and artificial menstrual cycle on the production of osteoprotegerin and the bone resorptive cytokines IL-1beta and IL-6

    DEFF Research Database (Denmark)

    Abrahamsen, Bo; Stilgren, L S; Rettmer, E;

    2003-01-01

    .1) without cycle irregularities. Postmenopausal women (n = 11, mean age 56.8 y +/- 3.6) receiving cyclic HRT (estradiol and noretisterone acetate). Luteal and follicular phase blood samples were diluted and cultured for 24 hours with and without lipopolysaccharide (LPS). The supernatant was assayed for IL-1...... in serum OPG. An increased cytokine secretory capacity of blood cells may be an epiphenomenon particular to the luteal phase but unrelated to bone metabolism....

  17. Mesenchymal dental pulp cells attenuate dentin resorption in homeostasis.

    Science.gov (United States)

    Zheng, Y; Chen, M; He, L; Marão, H F; Sun, D M; Zhou, J; Kim, S G; Song, S; Wang, S L; Mao, J J

    2015-06-01

    Dentin in permanent teeth rarely undergoes resorption in development, homeostasis, or aging, in contrast to bone that undergoes periodic resorption/remodeling. The authors hypothesized that cells in the mesenchymal compartment of dental pulp attenuate osteoclastogenesis. Mononucleated and adherent cells from donor-matched rat dental pulp (dental pulp cells [DPCs]) and alveolar bone (alveolar bone cells [ABCs]) were isolated and separately cocultured with primary rat splenocytes. Primary splenocytes readily aggregated and formed osteoclast-like cells in chemically defined osteoclastogenesis medium with 20 ng/mL of macrophage colony-stimulating factor (M-CSF) and 50 ng/mL of receptor activator of nuclear factor κB ligand (RANKL). Strikingly, DPCs attenuated osteoclastogenesis when cocultured with primary splenocytes, whereas ABCs slightly but significantly promoted osteoclastogenesis. DPCs yielded ~20-fold lower RANKL expression but >2-fold higher osteoprotegerin (OPG) expression than donor-matched ABCs, yielding a RANKL/OPG ratio of 41:1 (ABCs:DPCs). Vitamin D3 significantly promoted RANKL expression in ABCs and OPG in DPCs. In vivo, rat maxillary incisors were atraumatically extracted (without any tooth fractures), followed by retrograde pulpectomy to remove DPCs and immediate replantation into the extraction sockets to allow repopulation of the surgically treated root canal with periodontal and alveolar bone-derived cells. After 8 wk, multiple dentin/root resorption lacunae were present in root dentin with robust RANKL and OPG expression. There were areas of dentin resoprtion alternating with areas of osteodentin formation in root dentin surface in the observed 8 wk. These findings suggest that DPCs of the mesenchymal compartment have an innate ability to attenuate osteoclastogenesis and that this innate ability may be responsible for the absence of dentin resorption in homeostasis. Mesenchymal attenuation of dentin resorption may have implications in internal

  18. Diets based on virgin olive oil or fish oil but not on sunflower oil prevent age-related alveolar bone resorption by mitochondrial-related mechanisms.

    Directory of Open Access Journals (Sweden)

    Pedro Bullon

    Full Text Available BACKGROUND/OBJECTIVES: Aging enhances frequency of chronic diseases like cardiovascular diseases or periodontitis. Here we reproduced an age-dependent model of the periodontium, a fully physiological approach to periodontal conditions, to evaluate the impact of dietary fat type on gingival tissue of young (6 months old and old (24 months old rats. METHODS/FINDINGS: Animals were fed life-long on diets based on monounsaturated fatty acids (MUFA as virgin olive oil, n-6 polyunsaturated fatty acids (n-6PUFA, as sunflower oil, or n-3PUFA, as fish oil. Age-related alveolar bone loss was higher in n-6PUFA fed rats, probably as a consequence of the ablation of the cell capacity to adapt to aging. Gene expression analysis suggests that MUFA or n-3PUFA allowed mitochondria to maintain an adequate turnover through induction of biogenesis, autophagy and the antioxidant systems, and avoiding mitochondrial electron transport system alterations. CONCLUSIONS: The main finding is that the enhanced alveolar bone loss associated to age may be targeted by an appropriate dietary treatment. The mechanisms involved in this phenomenon are related with an ablation of the cell capacity to adapt to aging. Thus, MUFA or n-3PUFA might allow mitochondrial maintaining turnover through biogenesis or autophagy. They might also be able to induce the corresponding antioxidant systems to counteract age-related oxidative stress, and do not inhibit mitochondrial electron transport chain. From the nutritional and clinical point of view, it is noteworthy that the potential treatments to attenuate alveolar bone loss (a feature of periodontal disease associated to age could be similar to some of the proposed for the prevention and treatment of cardiovascular diseases, a group of pathologies recently associated with age-related periodontitis.

  19. Invasive cervical resorption: treatment challenges

    OpenAIRE

    2012-01-01

    Invasive cervical resorption is a relatively uncommon form of external root resorption. It is characterized by invasion of cervical region of the root by fibrovascular tissue derived from the periodontal ligament. This case presents an invasive cervical resorption occurring in maxillary lateral incisor, following damage in cervical cementum from avulsion and intracoronal bleaching procedure. Flap reflection, debridement and restoration with glass ionomer cement were performed in an attempt to...

  20. Nutrient resorption from seagrass leaves

    NARCIS (Netherlands)

    Stapel, J.; Hemminga, M.A.

    1997-01-01

    The resorption of nutrients (C, N and P) from senescent leaves of six seagrass species from nine different locations in tropical (Indonesia and Kenya), Mediterranean (Spain) and temperate (The Netherlands) regions has been investigated. Resorption was quantitatively assessed by calculating the diffe

  1. Osteoclasts secrete non-bone derived signals that induce bone formation

    DEFF Research Database (Denmark)

    Karsdal, Morten A; Neutzsky-Wulff, Anita V; Dziegiel, Morten Hanefeld

    2008-01-01

    Bone turnover is a highly regulated process, where bone resorption in the normal healthy individual always is followed by bone formation in a manner referred to as coupling. Patients with osteopetrosis caused by defective acidification of the resorption lacuna have severely decreased resorption, ...... secrete non-bone derived factors, which induce preosteoblasts to form bone-like nodules, potentially explaining the imbalanced coupling seen in osteopetrotic patients....

  2. A comparison of osteoclast-rich and osteoclast-poor osteopetrosis in adult mice sheds light on the role of the osteoclast in coupling bone resorption and bone formation

    DEFF Research Database (Denmark)

    Thudium, Christian S; Moscatelli, Ilana; Flores, Carmen

    2014-01-01

    that osteoclasts are important for regulating osteoblast activity. To illuminate the role of the osteoclast in controlling bone remodeling, we transplanted irradiated skeletally mature 3-month old wild-type mice with hematopoietic stem cells (HSCs) to generate either an osteoclast-rich or osteoclast-poor adult...... osteopetrosis model. We used fetal liver HSCs from (1) oc/oc mice, (2) RANK KO mice, and (3) compared these to wt control cells. TRAP5b activity, a marker of osteoclast number and size, was increased in the oc/oc recipients, while a significant reduction was seen in the RANK KO recipients. In contrast, the bone...

  3. Chapter 5 : Deciduous Tooth Resorption after Overfilling of Root Canal Filler: Function and Nature of Multinucleated Giant Cells

    OpenAIRE

    Hasegawa, Hiromasa; ANTOH, MOTOYOSHI; TAKEI, NORIYUYKI; OCHIAI, TAKANAGA

    2012-01-01

    There are numerous reports on physiological root resorption claiming that the root resorption process of primary teeth is regulated in a manner similar to bone remodeling [28]. However, complex histological changes occur under several pathological conditions. Abnormal tooth resorption could be found in primary teeth due to certain causes until the completion of the permanent dentition. In Japan and eastern Asia, calcium hydroxide paste with silicon oil added iodoform is widely used for endodo...

  4. Study on the correlations of alveolar bone resorption with the levels of IL-6, TNF-α and PGE2 in elderly patients with periodontitis%老年牙周病患者牙槽骨吸收与IL-6、TNF-α、PGE2水平相关性研究

    Institute of Scientific and Technical Information of China (English)

    韩建国; 王丽; 韩斐斐; 丁志江; 李健

    2011-01-01

    Objective To investigate the correlations of alveolar bone resorption with the levels of IL - 6, TNF - α and PGE2 in gingival crevicular fluid in elderly patient with periodontitis. Methods 40 periodontitis patients aged between 60 and 74 were selected as subjects with another 40 healthy elderly people as controls. The resorption percentages of alveolar bone were detected, and meanwhile the levels of the IL - 6, TNF - α and PGE2 in gingival crevicular fluid were determined by radiommunoassay. Results Compared to the healthy controls, the level of alveolar bone resorption were remarkably higher ( P < 0.01 ), and the level of IL - 6, TNF - α and PGE2 in gingival crevicular fluid significantly increased ( P < 0.05 or P < 0.01 ). Conclusion The alveolar resorption is positively correlated with the levels of IL - 6, TNF - α and PGE2 in gingival crevicular fluid.%目的探讨老年牙周病患者牙槽骨吸收与龈沟液白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、前列腺素E2(PGE2)水平的相关性.方法 选择60~74岁的牙周病患者40例,并选择牙周组织健康老人40例作为对照,测定牙槽骨骨吸收度情况,同时应用放射免疫法检测龈沟液中IL-6、TNF-α、PGE2含量.结果 与健康老年人比较,老年牙周病患者牙槽骨骨吸收度值明显升高(P<0.01),龈沟液中IL-6、TNF-α、PGE2含量均明显升高(P<0.05或P<0.01).结论 老年牙周病患者牙槽骨吸收与龈沟液内IL-6、TNF-α、PGE2水平呈正相关.

  5. Biocompatibility and resorption of a brushite calcium phosphate cement.

    Science.gov (United States)

    Theiss, Felix; Apelt, Detlef; Brand, Bastian; Kutter, Annette; Zlinszky, Katalin; Bohner, Marc; Matter, Sandro; Frei, Christian; Auer, Joerg A; von Rechenberg, Brigitte

    2005-07-01

    A hydraulic calcium phosphate cement with beta-tricalcium phosphate (TCP) granules embedded in a matrix of dicalcium phosphate dihydrate (DCPD) was implanted in experimentally created defects in sheep. One type of defect consisted of a drill hole in the medial femoral condyle. The other, partial metaphyseal defect was located in the proximal aspect of the tibia plateau and was stabilized using a 3.5 mm T-plate. The bone samples of 2 animals each per group were harvested after 2, 4, 6 and 8 weeks. Samples were evaluated for cement resorption and signs of immediate reaction, such as inflammation, caused by the cement setting in situ. Differences regarding these aspects were assessed for both types of defects using macroscopical, radiological, histological and histomorphometrical evaluations. In both defects the brushite matrix was resorbed faster than the beta-TCP granules. The resorption front was followed directly by a front of new bone formation, in which residual beta-TCP granules were embedded. Cement resorption occurred through (i) extracellular liquid dissolution with cement disintegration and particle formation, and (ii) phagocytosis of the cement particles through macrophages. Signs of inflammation or immunologic response leading to delayed new bone formation were not noticed at any time. Cement degradation and new bone formation occurred slightly faster in the femur defects.

  6. 正畸力作用下垂直型骨吸收牙周炎大鼠牙槽骨改建的实验研究%Periodontitis with vertical bone resorption under orthodontic force bone remodeling in rats

    Institute of Scientific and Technical Information of China (English)

    姚霜; 刘晓君; 周治; 杨鸘; 季娟娟; 沈勇

    2016-01-01

    目的:观察正畸力作用下牙周炎大鼠垂直吸收的牙槽骨改建,为牙周炎的临床正畸治疗提供依据。方法:将75只10周龄雄性SD大鼠,随机分为3组,正常加力对照组( A)、牙周炎垂直骨吸收对照组( B)、牙周炎垂直骨吸收加力实验组( C),每组各25只,各组动物分别于加力后8 h,1、7、14、21 d处死,取动物模型上颌左侧第一磨牙近中牙槽骨进行组织学及免疫学检测,所得结果进行对比研究。结果:正畸加力至7d时,实验组大鼠垂直吸收侧牙周膜纤维排列紊乱,出现无细胞结构,结缔组织可见少量炎症细胞,牙槽骨表面还可见功能活跃的多核破骨细胞,与对照组相比较无显著差异,实验组大鼠牙周组织中IGF⁃1表达达到峰值,光密度值最高,与对照组比较有显著差异( P<0.05);加力至14 d时,实验组大鼠垂直吸收侧牙周组织中RUNX2的表达达到峰值,其光密度值最高,明显高于正常加力对照组,其变化有统计学意义(P<0.05)。结论:控制牙周炎症和消除咬合创伤后,正畸力能刺激牙周炎大鼠垂直缺损牙槽骨区域的RUNX2和IGF⁃1的表达增强,合成骨胶原和骨基质的能力增强,从而促进牙槽骨的改建。%Objective:To observe the remodeling of alveolar bone in rats with the vertical absorption after loading orthodontic force, and to provide evidence for clinical orthodontic treatment. Methods:75 SD rats ( 10⁃week⁃old ,male) were randomly divided into three groups(25 in each group):loading force control group (A), control group of periodontitis with vertical bone absorption (B), loading force group to periodontitis with vertical bone absorption (C). With loading force on for 8 hours, 1d,7d, 14d and 21d,the alveolar bone of the first molar of left maxillary were taken to do the histological and immunological detection. Results:On the 7th day, the de

  7. Ion transporters involved in acidification of the resorption lacuna in osteoclasts

    DEFF Research Database (Denmark)

    Henriksen, K.; Sorensen, M.G.; Jensen, V.K.;

    2008-01-01

    Osteoclasts possess a large amount of ion transporters, which participate in bone resorption; of these, the vacuolar-adenosine trisphosphatase (V-ATPase) and the chloride-proton antiporter ClC-7 acidify the resorption lacuna. However, whether other ion transporters participate in this process...... is currently not well understood. We used a battery of ion channel inhibitors, human osteoclasts, and their subcellular compartments to perform an unbiased analysis of the importance of the different ion transporters for acidification of the resorption lacuna in osteoclasts. CD14(+) monocytes from human...... peripheral blood were isolated, and mature osteoclasts were generated using RANKL and M-CSF. The human osteoclasts were (1) used for acridine orange assays for evaluation of lysosomal acidification, (2) used for bone resorption assays, (3) used for generation of osteoclasts membranes for acid influx...

  8. Preeruptive intracoronal resorption observed in 13 patients

    DEFF Research Database (Denmark)

    Kjær, Inger; Steiniche, Kirsten; Kortegaard, Ulla;

    2012-01-01

    The literature on preeruptive intracoronal resorption is sparse, comprising mainly reports of single patients. This study includes 13 patients with preeruptive intracoronal resorption, forwarded for consultation regarding diagnostics and etiology. The purposes were to determine which teeth are af...

  9. 成人上颌牙牙根吸收及牙槽骨改建的 CBCT分析%Evaluation for apical root resorption and alveolar bone reconstruction in-duced by orthodontic treatment of maxillary in adult patients by CBCT

    Institute of Scientific and Technical Information of China (English)

    杨亚欣; 杨亚普; 王晨曦; 王鹿鸣; 张月兰

    2016-01-01

    目的:探讨正畸治疗的上颌前突患者上颌牙牙根吸收及牙槽骨改建情况。方法:选取上颌前突患者15例,均拔除上下颌第一前磨牙进行治疗。治疗前及拔牙间隙关闭后分别拍摄CBCT,观察牙根吸收及中切牙区牙槽骨改建情况。结果:拔牙间隙关闭后,所有患者均被检测出有牙根吸收,中切牙、侧切牙、尖牙和第二前磨牙吸收量分别为(0.415±0.118)、(0.972±0.288)、(0.466±0.718)和(0.283±0.339) mm。在中切牙颈部唇侧、根尖舌侧牙槽骨增厚,颈部舌侧、根中唇侧、根尖唇侧牙槽骨变薄,牙齿倾斜移动;在颈部、根中部以及根尖部水平总牙槽骨厚度的改变不具有统计学意义(P>0.05)。结论:正畸治疗后几乎所有牙齿均有一定程度的牙根吸收。前牙在内收过程中倾斜移动。%Aim:To evaluate orthodontically induced apical root resorption and alveolar bone reconstruction in maxil -lary teeth.Methods:A total of 15 patients receiving standardized orthodontic fixed appliance treatment with straight wire technique and first premolar extraction .Cone beam computed tomography ( CBCT ) examination was performed before and after closing the extraction space to observe the prevalence and severity of apical root resorption and alveolar bone recon -struction of central incisor .Results: After closing the spaces , apical root resorption was detected in all the patients; the apical root resorption values of central incisor , lateral incisor, canine and second premolar were ( 0.415 ±0.118 ), (0.972 ±0.288),(0.466 ±0.718) and (0.283 ±0.339) mm, respectively.Alveolar bone width increased significantly at the coronal level of labial side and the apical level of lingual side , decreased at the coronal level of lingual side and the apical level of labial side , and the teeth tipping moved;but the total alveolar bone width changes had no significance at co

  10. Orthopantomographic study of the alveolar bone level on periodontal disease

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ki Sik; You, Dong Soo [College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1972-11-15

    The author had measured the alveolar bone level of periodontal disease on 50 cases of orthopantomogram to detect the degree of alveolar bone resorption of both sexes of Korean. The results were obtained as follows; 1. Alveolar bone resorption of mesial and distal portion was similar in same patient. 2. The order of alveolar bone resorption was mandibular anterior region, posterior region, canine and premolar region of both jaws. 3. The degree of alveolar bone destruction was severe in shorter root length than longer one. 4. The degree of alveolar bone resorption was severe in fourth decades.

  11. Influence of anatomical barriers on maxillary incisor root resorption after orthodontic treatment with premolar extractions

    OpenAIRE

    2012-01-01

    INTRODUCTION: Apical root resorption is a frequent and occasionally critical problem in orthodontic patients undergoing induced tooth movement. One of the factors that might influence prognosis, especially in maxillary incisors, which most frequently present resorptions, are the so-called the anatomical barriers; that is, proximity of the buccal and palatal cortical bones to the maxillary incisor roots. OBJECTIVE: The purpose of this research was to investigate whether patients with excessive...

  12. Influence of anatomical barriers on maxillary incisor root resorption after orthodontic treatment with premolar extractions

    Directory of Open Access Journals (Sweden)

    Antonio Geraldo de Oliveira

    2012-04-01

    Full Text Available INTRODUCTION: Apical root resorption is a frequent and occasionally critical problem in orthodontic patients undergoing induced tooth movement. One of the factors that might influence prognosis, especially in maxillary incisors, which most frequently present resorptions, are the so-called the anatomical barriers; that is, proximity of the buccal and palatal cortical bones to the maxillary incisor roots. OBJECTIVE: The purpose of this research was to investigate whether patients with excessive vertical growth really present a small distance between the alveolar cortical bones and the maxillary incisor roots, and whether there is a correlation between this distance and the root resorption index in comparison with patients presenting horizontal growth. METHODS: The sample comprised orthodontic records of 18 patients with extraction planning of first maxillary premolars and treatment by the standard and/or preadjusted edgewise brackets. Their initial and final periapical radiographs were evaluated to determine the amount of root resorption that occurred. RESULTS: On the palatal side, patients with excessive vertical growth (Group 2 - SN-GoGn > 43º showed a narrower alveolar bone than the horizontal growth patients (Group 1 - SN-GoGn < 29º. However, the distance between the buccal cortical bone and the central incisor root apex showed no significant difference between Groups 1 and 2; CONCLUSIONS: It was concluded that there are no correlations between the proximity of buccal cortical bone, maxillary incisor roots and the root resorption index.

  13. The role of calcium and nicotinic acid adenine dinucleotide phosphate (NAADP) in human osteoclast formation and resorption.

    Science.gov (United States)

    Cheng, X; Hookway, E S; Kashima, T; Oppermann, U; Galione, A; Athanasou, N A

    2015-01-01

    Osteoclasts are specialised bone resorbing cells which form by fusion of circulating mononuclear phagocyte precursors. Bone resorption results in the release of large amounts of calcium into the extracellular fluid (ECF), but it is not certain whether changes in extracellular calcium concentration [Ca(2+)]e influence osteoclast formation and resorption. In this study, we sought to determine the effect of [Ca(2+)]e and NAADP, a potent calcium mobilising messenger that induces calcium uptake, on human osteoclast formation and resorption. CD14+ human monocytes were cultured with M-CSF and RANKL in the presence of different concentrations of calcium and NAADP and the effect on osteoclast formation and resorption evaluated. We found that the number of TRAP+ multinucleated cells and the extent of lacunar resorption were reduced when there was an increase in extracellular calcium and NAADP. This was associated with a decrease in RANK mRNA expression by CD14+ cells. At high concentrations (20 mM) of [Ca(2+)]e mature osteoclast resorption activity remained unaltered relative to control cultures. Our findings indicate that osteoclast formation is inhibited by a rise in [Ca(2+)]e and that RANK expression by mononuclear phagocyte osteoclast precursors is also [Ca(2+)]e dependent. Changes in NAADP also influence osteoclast formation, suggesting a role for this molecule in calcium handling. Osteoclasts remained capable of lacunar resorption, even at high ECF [Ca(2+)]e, in keeping with their role in physiological and pathological bone resorption.

  14. Clinical technique for invasive cervical root resorption

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Machado Silveira

    2011-01-01

    Full Text Available This clinical case report describes the diagnosis and treatment of an external invasive cervical resorption. A 17-year-old female patient had a confirmed diagnosis of invasive cervical resorption class 4 by cone beam computerized tomography. Although, there was no communication with the root canal, the invasive resorption process was extending into the cervical and middle third of the root. The treatment of the cervical resorption of the lateral incisor interrupted the resorptive process and restored the damaged root surface and the dental functions without any esthetic sequelae. Both the radiographic examination and computed tomography are imperative to reveal the extent of the defect in the differential diagnosis.

  15. O papel do Fator de Necrose Tumoral Alfa (TNF-alfa no processo de erosão óssea presente no colesteatoma adquirido da orelha média The role of Tumor Necrosis Factor -Alpha (TNF- alpha in bone resorption present in middle ear cholesteatoma

    Directory of Open Access Journals (Sweden)

    Rodrigo Faller Vitale

    2007-02-01

    Full Text Available O colesteatoma adquirido da orelha média causa erosão óssea, com altas taxas de morbidade e mortalidade. O TNF-alfa (TNF-alfa lambda uma das principais citocinas envolvidas neste processo. OBJETIVO: Avaliar o papel do TNF-alfa na reabsorsão óssea e a ação dele no colesteatoma. MATERIAL E MÉTODOS: Foi realizado um levantamento e uma revisão crítica da literatura. RESULTADOS: Todos os autores estudados concordam com a importância do TNF-alfa no processo de reabsorção óssea presente no colesteatoma e com o grau de destruição observado. Diferentes trabalhos demonstraram que o TNF-alfa é capaz de provocar erosão óssea, através de diferentes vias de ação. Ele pode estimular a diferenciação e a maturação dos osteoclastos ou, ainda, agir na matriz óssea expondo-a à ação dos osteoclastos. Existe a possibilidade de inibir a ação do TNF-alfa, diminuindo seus efeitos e prevenindo a perda óssea em doenças como a artrite reumatóide. Não existe, entretanto, trabalhos específicos em colesteatoma. Não existe consenso sobre a sua localização. Estas diferenças, provavelmente, ocorrem devido à distribuição dos receptores. CONCLUSÃO: O TNF-alfa, presente no colesteatoma promove a reabsorsão óssea, juntamente com outras citocinas (RANKL e IL-1, estando relacionado com a presença de complicações.Cholesteatoma may cause bone erosion, with high morbidity and mortality rates. Tumor Necrosis Factor -Alpha (TNF-a is one of the main cytokines involved in this process. Our goal was to evaluate the role of TNF-a in Bone Resorption and its effect on cholesteatoma. MATERIAL AND METHODS: analysis and critical literature review. RESULTS: Different studies have demonstrated that TNF-a is capable of causing bone erosion. It may stimulate the differentiation and maturation of osteoclasts or it may act on the bone matrix, exposing it to the action of the osteoclasts. It is possible to inhibit TNF-a, reducing its effects and prevent

  16. The four mechanisms of dental resorption initiation

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    2013-06-01

    Full Text Available The aim of this study is to present a classification with a clinical application for root resorption, so that diagnosis will be more objective and immediately linked to the source of the problem, leading the clinician to automatically develop the likely treatment plan with a precise prognosis. With this purpose, we suggest putting together all diagnosed dental resorptions into one of these four criteria: 1 Root resorption caused by cementoblast cell death, with preservation of the Malassez epithelial rests. 2 Root resorption by cementoblasts and Malassez epithelial rests death. 3 Dental resorption by odontoblasts cell death with preservation of pulp vitality. 4 Dental resorption by direct exposure of dentin to gingival connective tissue at the cementoenamel junction gaps.

  17. Operating protocols of external root cervical resorption

    OpenAIRE

    Luca Venuti

    2015-01-01

    Aim: Theme of this report is the external cervical root resorption and the sequence of clinical procedures to be implemented during the phases of treatment. The external cervical root resorption (ICR) presents particular pathological conditions such as to classify between resorption of inflammatory origin.1–3 It is generally presented as a complex clinical situation both in the diagnosis in a predictable prognosis.3–6 It's often associated with loss of calcified tissue: dentin, cementum, a...

  18. TGF-β in cancer and bone: implications for treatment of bone metastases.

    Science.gov (United States)

    Juárez, Patricia; Guise, Theresa A

    2011-01-01

    Bone metastases are common in patients with advanced breast, prostate and lung cancer. Tumor cells co-opt bone cells to drive a feed-forward cycle which disrupts normal bone remodeling to result in abnormal bone destruction or formation and tumor growth in bone. Transforming growth factor-beta (TGF-β) is a major bone-derived factor, which contributes to this vicious cycle of bone metastasis. TGF-β released from bone matrix during osteoclastic resorption stimulates tumor cells to produce osteolytic factors further increasing bone resorption adjacent to the tumor cells. TGF-β also regulates 1) key components of the metastatic cascade such as epithelial-mesenchymal transition, tumor cell invasion, angiogenesis and immunosuppression as well as 2) normal bone remodeling and coupling of bone resorption and formation. Preclinical models demonstrate that blockade of TGF-β signaling is effective to treat and prevent bone metastases as well as to increase bone mass.

  19. COMPUTED TOMOGRAPHY OF TOOTH RESORPTION IN CATS.

    Science.gov (United States)

    Lang, Linda G; Wilkinson, Thomas E; White, Tammy L; Farnsworth, Raelynn K; Potter, Kathleen A

    2016-09-01

    Tooth resorption is the most common dental disease in cats and can be a source of oral pain. The current clinical gold standard for diagnosis includes a combination of oral exam and dental radiography, however early lesions are not always detected. Computed tomography (CT) of the skull, including the dental arches, is a commonly performed diagnostic procedure, however the appearance of tooth resorption on CT and the diagnostic ability of CT to detect tooth resorption have not been evaluated. The purpose of this prospective, descriptive, diagnostic accuracy study was to characterize the CT appearance of tooth resorption in a sample of affected cats and to evaluate the sensitivity and specificity of CT for tooth resorption compared to the clinical gold standard of oral exam and intraoral dental radiography. Twenty-eight cat cadaver specimens were recruited for inclusion. Each specimen was evaluated using oral exam, intraoral dental radiography, and computed tomography (four different slice thicknesses). Each tooth was evaluated for the presence or absence of tooth resorption. Teeth with lesions and a subset of normal teeth were evaluated with histopathology. On CT, tooth resorption appeared as irregularly marginated hypoattenuating defects in the mineral attenuating tooth components, most commonly involving the root or cementoenamel junction. Sensitivity for CT detection of tooth resorption was fair to poor (42.2-57.7%) and specificity was good to excellent (92.8-96.3%). Findings from this study indicated that CT has high specificity but low sensitivity for detection of tooth resorption in cats.

  20. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  1. 用尿脱氧吡啶啉及羟脯氨酸排泄率评价肾病综合征患儿骨吸收功能状况%Evaluation bone resorption activity of childhood nephrotic syndrome with urinary deoxypyridinoline and hydroxyproline

    Institute of Scientific and Technical Information of China (English)

    窦志艳; 张会丰; 田秀巧; 耿佩琛; 刘艳平; 王丽芳

    2001-01-01

    目的 观察糖皮质激素(激素)对肾病综合征(肾病)患儿骨吸收功能的影响。方法 采用酶联免疫竞争法和分光光度比色法,对68例泼尼松治疗不同阶段的肾病患儿及同龄健康儿童16例尿脱氧吡啶啉(DPD)及羟脯氨酸(HOP)进行检测。结果 (1)激素足量治疗组DPD/肌酐(Cr)为(30±17) nmol/mmol,较正常对照组[(21±5) nmol/mmol]、初发激素治疗前组[(20±8) nmol/mmol]及激素减量治疗组[(20±11) nmol/mmol]均有升高(P均<0.05);(2)与DPD/Cr值变化趋势一致,激素足量治疗组HOP/Cr为[(5.3±2.7)mg/mmol],与正常对照组[(3.2±1.2)mg/mmol]、初发激素治疗前组[(3.5±0.9)mg/mmol]及激素减量治疗组[(3.7±1.7)mg/mmol]比较差异均有显著意义(P<0.05, <0.01, <0.05);(3)DPD/Cr与HOP/Cr两指标在正常对照组及肾病各组均呈明显正相关(r=0.64、0.65、0.76、0.78,P均<0. 01)。结论 超生理剂量的泼尼松治疗能使肾病患儿骨吸收功能增强,易导致骨质疏松。%Osteoporosis is one of the major side -effects in the treatment of nephritic syndrome with glucocorticoids, but the exact mechanism of osteopenia is not completely understood. Excess glucocorticoids will induce a reduction of bone formation as well as an increase of bone resorption on the other hand. Objective  To analyze the effect of glucocorticoid on the bone resorption activity of childhood nephrotic syndrome (CNS). Methods The bone resorption activities in 68 cases of CNS were evaluated by measuring urinary deoxypyridinoline (DPD) and urinary hydroxyproline (HOP). The patients were divided into three groups. The prednisone-pretreatment group included 25 children (19 boys and 6 girls) aged 4-11 years old without the prednisone treatment. The full dose prednisone group included 25 children (17 boys and 8 girls) aged 4-12 years old with the prednisone treatment [2 mg/(kg*d)] of 4-6 weeks. The

  2. Conservative Management of Invasive Cervical Resorption: A Case Report

    Directory of Open Access Journals (Sweden)

    Farhan Raza Khan

    2013-01-01

    Full Text Available Invasive cervical resorption is a condition that affects the root surface area below the epithelial attachment. Multiple treatment modalities are advocated, involving exposure of the invasive defect, removal of the granulation tissue and sealing with various restorative materials. This report demonstrates conservative treatment of a patient presenting with peri-apical periodontitis in upper right central and lateral incisors, along with Class II invasive resorption defect cervically on the mesial aspect of the central incisor, as a result of trauma. As the patient was not willing for any surgical intervention, only ortho-grade root canal treatment was carried out in both teeth, with Calcium hydroxide as intra-canal medicament. At three year follow-up, the patient remains asymptomatic demonstrating radiographic evidence of infilling of defect with bone-like tissue.Within the limitations of this report, it was seen that this conservative method for halting the progression of invasive cervical resorption could be under taken in patients who are un-willing for surgical intervention or in whom surgery is contra-indicated.

  3. Variation in nutrient resorption by desert shrubs

    Science.gov (United States)

    Plant nutrient resorption prior to leaf senescence is an important nutrient conservation mechanism for aridland plant species. However, little is known regarding the phylogenetic and environmental factors influencing this trait. Our objective was to compare nitrogen and phosphorus resorption in a ...

  4. Bone metabolism in advanced cholestatic liver disease : Analysis by bone histomorphometry

    NARCIS (Netherlands)

    Guichelaar, MMJ; Malinchoc, M; Sibonga, J; Clarke, BL; Hay, JE

    2002-01-01

    Despite the clinical importance of cholestatic osteopenia, little is known about its pathophysiologic mechanism. By tetracycline-labeled histomorphometric analysis of bone biopsies taken at the time of liver transplantation, we prospectively evaluated bone resorption and formation in 50 consecutive

  5. The Effect of Root Coating with Titanium on Prevention of Root Resorption in Avulsed Teeth: An Animal Study

    Science.gov (United States)

    Heydari, Azar; Tahmasbi, Soodeh; Badiee, Mohammadreza; Izadi, SeyedSadra; Mashhadi Abbas, Fatemeh; Mokhtari, Sepideh

    2016-01-01

    Introduction: Tooth avulsion is a real dental emergency. If immediate replantation is not performed, the avulsed tooth may be lost due to inflammatory or replacement resorption. This animal study aimed to evaluate the bone response to the titanium coating of the root surface as an artificial barrier, and prevention of resorption of avulsed teeth. Methods and Materials: This experimental study was conducted on four male dogs. The dogs were randomly divided into two groups for assessment at two and eight weeks. Four teeth were extracted in each animal. The root surfaces of the test group were coated with a titanium layer using the Electron Beam Deposition system. After 24 h, replantation of the teeth was performed. Two animals were sacrificed after two weeks and the remaining dogs were killed after eight weeks. The presence of inflammation, inflammatory resorption, replacement resorption, periodontal regeneration, periapical granuloma and ankylosis were evaluated through histological analyses. Results: Inflammatory root resorption was not present in any tooth except one tooth in the coated group after eight weeks. Replacement resorption was noted just in three of the non-coated teeth after two weeks and two teeth after eight weeks. The McNemar's test revealed that the frequency of replacement resorption in the non-coated group was significantly higher than the coated group (P=0.031). Conclusion: Based on the results of this study, it seems that coating the root surfaces of avulsed teeth with titanium may control the replacement root resorption. PMID:27790261

  6. In vitro degradation and in vivo resorption of dicalcium phosphate cement based grafts.

    Science.gov (United States)

    Sheikh, Zeeshan; Zhang, Yu Ling; Grover, Liam; Merle, Géraldine E; Tamimi, Faleh; Barralet, Jake

    2015-10-01

    There are two types of DCP: dihydrated (brushite) and anhydrous (monetite). After implantation, brushite converts to hydroxyapatite (HA) which resorbs very slowly. This conversion is not observed after implantation of monetite cements and result in a greater of resorption. The precise mechanisms of resorption and degradation however of these ceramics remain uncertain. This study was designed to investigate the effect of: porosity, surface area and hydration on in vitro degradation and in vivo resorption of DCP. Brushite and two types of monetite cement based grafts (produced by wet and dry thermal conversion) were aged in phosphate buffered saline (PBS) and bovine serum solutions in vitro and were implanted subcutaneously in rats. Here we show that for high relative porosity grafts (50-65%), solubility and surface area does not play a significant role towards in vitro mass loss with disintegration and fragmentation being the main factors dictating mass loss. For grafts having lower relative porosity (35-45%), solubility plays a more crucial role in mass loss during in vitro ageing and in vivo resorption. Also, serum inhibited dissolution and the formation of HA in brushite cements. However, when aged in PBS, brushite undergoes phase conversion to a mixture of octacalcium phosphate (OCP) and HA. This phase conversion was not observed for monetite upon ageing (in both serum and PBS) or in subcutaneous implantation. This study provides greater understanding of the degradation and resorption process of DCP based grafts, allowing us to prepare bone replacement materials with more predictable resorption profiles.

  7. Osteoclast resorption of beta-tricalcium phosphate controlled by surface architecture.

    Science.gov (United States)

    Davison, Noel L; ten Harkel, Bas; Schoenmaker, Ton; Luo, Xiaoman; Yuan, Huipin; Everts, Vincent; Barrère-de Groot, Florence; de Bruijn, Joost D

    2014-08-01

    A resorbable bone graft substitute should mimic native bone in its capacity to support bone formation and be remodeled by osteoclasts (OCl) or other multinucleated cells such as foreign body giant cells (FBGC). We hypothesize that by changing the scale of surface architecture of beta-tricalcium phosphate (TCP), cellular resorption can be influenced. CD14(+) monocyte precursors were isolated from human peripheral blood (n = 4 independent donors) and differentiated into OCl or FBGC on the surface of TCP discs comprising either submicron- or micron-scale surface topographical features (TCPs and TCPb, respectively). On submicrostructured TCPs, OCl survived, fused, differentiated, and extensively resorbed the substrate; however, on microstructured TCPb, OCl survival, TRAP activation, and fusion were attenuated. Importantly, no resorption was observed on microstructured TCPb. By confocal microscopy, OCl formed on TCPs contained numerous actin rings allowing for resorption, but not on TCPb. In comparison, FBGC could not resorb either TCP material, suggesting that osteoclast-specific machinery is necessary to resorb TCP. By tuning surface architecture, it appears possible to control osteoclast resorption of calcium phosphate. This approach presents a useful strategy in the design of resorbable bone graft substitutes.

  8. Trabecular architecture can remain intact for both disuse and overload enhanced resorption characteristics.

    NARCIS (Netherlands)

    Tanck, E.J.M.; Ruimerman, R.; Huiskes, R.

    2006-01-01

    The paradigm that bone metabolic processes are controlled by osteocyte signals have been the subject of investigation in many recent studies. One hypothesis is that osteoblast formation is enhanced by these signals, and that osteoclast resorption is enhanced by the lack of them. Reduced, or absent,

  9. Root resorption during orthodontic tooth movements.

    Science.gov (United States)

    Ramanathan, C; Hofman, Z

    2009-12-01

    The aim of the study was to compare the extent of maxillary incisor root resorption during different orthodontic tooth movements using three different techniques, namely the basal intrusion arch, the three component arch, and levelling of the upper dental arch with the straightwire appliance. The radiographs of 49 subjects (20 males and 29 females) with a mean age of 14.5 years were taken at two time points: in groups 1 and 2 after the levelling phase and in group 3 immediately after placement of the archwire (T1) and in all groups after a period of 6 months (T2). The amount of root resorption of the central incisors was determined at T2. The average incisor resorption was different in the three groups, with group 2 (three component arch) showing greater resorption (0.46 mm) than groups 1 (basal arch) and 3 (straightwire) of 0.26 and 0.25 mm, respectively. Analysis of variance (ANOVA) demonstrated that differences in root resorption in the three groups were not significant. Wilcoxon paired test showed that the root resorption occurring between T1 and T2 in the three groups was not significant. There was also no significant difference among the rates of resorption in the three groups. Grouping the subjects on the basis of the extent of root resorption and the biomechanics used showed differences in the percentage of subjects with the least (resorption between the three groups. This again showed that the technique of three component intrusion arch resulted in the greatest increase in root resorption.

  10. Estrogen directly attenuates human osteoclastogenesis, but has no effect on resorption by mature osteoclasts

    DEFF Research Database (Denmark)

    Sørensen, M G; Henriksen, K; Dziegiel, Morten Hanefeld;

    2006-01-01

    Estrogen deficiency arising with the menopause promotes marked acceleration of bone resorption, which can be restored by hormone replacement therapy. The inhibitory effects of estrogen seem to involve indirect cytokine- mediated effects via supporting bone marrow cells, but direct estrogen......-receptor mediated effects on the bone-resorbing osteoclasts have also been proposed. Little information is available on whether estrogens modulate human osteoclastogenesis or merely inhibit the functional activity of osteoclasts. To clarify whether estrogens directly modulate osteoclastic activities human CD14...... not affect bone resorption or TRACP activity. We investigated expression of the estrogen receptors, using immunocytochemistry and Western blotting. We found that ER-alpha is expressed in osteoclast precursors, whereas ER- beta is expressed at all stages, indicating that the inhibitory effect of estrogen...

  11. Notch2 signaling promotes osteoclast resorption via activation of PYK2.

    Science.gov (United States)

    Jin, Won Jong; Kim, Bongjun; Kim, Jung-Wook; Kim, Hong-Hee; Ha, Hyunil; Lee, Zang Hee

    2016-05-01

    Notch signaling plays a central role in various cell fate decisions, including skeletal development. Recently, Notch signaling was implicated in osteoclast differentiation and maturation, including the resorption activity of osteoclasts. However, the specific involvement of notch signaling in resorption activity was not fully investigated. Here, we investigated the roles of Notch signaling in the resorption activity of osteoclasts by use of the gamma-secretase inhibitor dibenzazepine (DBZ). Attenuating Notch signaling by DBZ suppressed the expression of NFATc1, a master transcription factor for osteoclast differentiation. However, overexpression of a constitutively active form of NFATc1 did not fully rescue the effects of DBZ. DBZ suppressed the autophosphorylation of PYK2, which is essential for the formation of the podosome belt and sealing zone, with reduced c-Src/PYK2 interaction. We found that RANKL increases PYK2 activation accompanied by increased NICD2 production in osteoclasts. Overexpression of NICD2 in osteoclasts rescued DBZ-mediated suppression of resorption activity with promotion of PYK2 autophosphorylation and microtubule acetylation. Consistent with the in vitro results, DBZ strongly suppressed bone destruction in an interleukin-1-induced bone loss model. Collectively, these results demonstrate that Notch2 in osteoclasts plays a role in the control of resorption activity via the PYK2-c-Src-microtubule signaling pathway.

  12. Prevention and management of external inflammatory resorption following trauma to teeth.

    Science.gov (United States)

    Abbott, P V

    2016-03-01

    External inflammatory resorption is one of the potential consequences of trauma to the teeth. It occurs when there has been loss of cementum due to damage to the external surface of the tooth root during trauma, plus the root canal system has become infected with bacteria. It is characterized by the radiographic appearance of loss of tooth substance with a radiolucency in the adjacent periodontal ligament and bone. The loss of cementum allows the intracanal bacteria and/or their endotoxins to reach the periodontal ligament more readily and this can lead to the development of the inflammatory resorptive process. External inflammatory resorption can ultimately lead to loss of the tooth if it is not managed in a timely manner. There are some injuries that are very likely to develop this type of resorption and a preventive approach can be adopted by commencing root canal treatment immediately as part of the emergency management of such cases. In cases where the resorptive process is already established, root canal treatment can arrest the resorption and encourage hard tissue repair. The use of a corticosteroid-antibiotic intracanal medicament has been shown to be particularly useful in the prevention and management of external inflammatory resorption. Calcium hydroxide should not be used as an immediate medicament because of its inherent toxicity and irritant properties but it is valuable as a subsequent medicament to encourage hard tissue repair where required. This review outlines the external inflammatory resorptive process and the management strategies that can be employed to prevent it from occurring, and to treat it if already present.

  13. A diet high in meat protein and potential renal acid load increases fractional Ca absorption and urinary Ca excretion, without affecting markers of bone resorption or formation in postmenopausal women

    Science.gov (United States)

    Objective: The objective was to determine the effects of high dietary protein (mostly meat) and high potential renal acid load (PRAL) on calcium (Ca) balance and markers of bone metabolism. Methods: In a randomized crossover design, sixteen healthy postmenopausal women consumed two diets: one with l...

  14. [Decoronation: treatment protocol for ankylotic root resorption as a consequence of dental trauma].

    Science.gov (United States)

    Lin, S; Fuss, Z; Wigler, R; Karawani, M; Ashkenazi, M

    2013-10-01

    Severe dental traumatic injuries, such as the complete displacement of a tooth from its socket (Avulsion) or the displacement of a tooth within its socket (Intrusive Luxation), may result in extensive injury to the root surface. As a result, the root surface injury heals without cementum and there is fusion between the alveolar bone and the exposed dentin or anorganic exposed cementum, without any attachment apparatus between them. This phenomenon is known as "dento-alveolar ankylosis" and is accompanied by ankylotic resorption of the root. In a process that results subsequent to the ankylosis, the root surface resorbs, and this is part of the remodeling of the alveolar bone (ankylotic resorption). When the traumatic injury occurs at a young age, lateral and apical growth of the alveolar bone continues without continued physiological eruption of the tooth. As a result, the position of the ankylotic tooth does not change, and with time thetooth appears infra-occluded resulting in severe esthetic and functional consequences. Extraction of the ankylotic tooth is difficult and sometimes even impossible due to the rigid fusion between the bone and the tooth. In addition, attempted extraction of the ankylotic tooth may lead to fracture of the buccal plate and resorption of the alveolar bone. Retention of the ankylotic tooth may lead to damage in bone deposition in the verticaldimension, leading to difficulties in future prosthodonticrehabilitation, research-based information has been incorporated

  15. Glucose-dependent insulinotropic polypeptide (GIP) dose-dependently reduces osteoclast differentiation and resorption.

    Science.gov (United States)

    Mabilleau, Guillaume; Perrot, Rodolphe; Mieczkowska, Aleksandra; Boni, Sébastien; Flatt, Peter R; Irwin, Nigel; Chappard, Daniel

    2016-10-01

    A role for glucose-dependent insulinotropic polypeptide (GIP) in controlling bone resorption has been suspected. However uncertainty remains to identify whether GIP act directly on osteoclasts. The aim of the present study were (i) to identify in different osteoclast differentiation models (human peripheral blood mononuclear cells-PBMC, murine bone marrow macrophage-BMM and murine Raw 264.7 cells) whether GIP was capable of reducing osteoclast formation and resorption; (ii) ascertain whether the highly potent GIP analogue N-AcGIP was capable of inducing a response at lower concentrations and (iii) to decipher the molecular mechanisms responsible for such effects. [d-Ala(2)]-GIP dose-dependently reduced osteoclast formation at concentration as low as 1nM in human PBMC and 10nM in murine BMM cultures. Furthermore, [d-Ala(2)]-GIP also reduced the extent of osteoclast resorption at concentration as low as 1nM in human PBMC and murine BMM cultures. The mechanism of action of [d-Ala(2)]-GIP appeared to be mediated by reduction in intracellular calcium concentration and oscillation that subsequently inhibited calcineurin activity and NFATc1 nuclear translocation. The potency of the highly potent N-AcGIP was determined and highlighted an effect on osteoclast formation and resorption at concentration ten times lower than observed with [d-Ala(2)]-GIP in vitro. Furthermore, N-AcGIP was also capable of reducing the number of osteoclast in ovariectomized mice as well as the circulating level of type I collagen C-telopeptide. Pharmacological concentrations required for reducing osteoclast formation and resorption provide the impetus to design and exploit enzymatically stable GIP analogues for the treatment of bone resorption disorders in humans.

  16. Animal Models of Bone Loss in Inflammatory Arthritis: from Cytokines in the Bench to Novel Treatments for Bone Loss in the Bedside—a Comprehensive Review

    NARCIS (Netherlands)

    C.H. Alves (Celso Henrique); E. Farrell (Eric); M. Vis (M.); E.M. Colin (Edgar); E.W. Lubberts (Erik)

    2016-01-01

    textabstractThroughout life, bone is continuously remodelled. Bone is formed by osteoblasts, from mesenchymal origin, while osteoclasts induce bone resorption. This process is tightly regulated. During inflammation, several growth factors and cytokines are increased inducing osteoclast differentiati

  17. Osteoarthritis, osteoarthrosis, and idiopathic condylar resorption.

    Science.gov (United States)

    Mercuri, Louis G

    2008-05-01

    The term "osteoarthritis" has classically been defined as a low-inflammatory arthritic condition. The term "osteoarthrosis," a synonym for osteoarthritis in the medical orthopedic literature, has recently come to be identified in the dental/temporomandibular joint (TMJ) disorders literature with any noninflammatory arthritic condition that results in similar degenerative changes as in osteoarthritis. The term "idiopathic condylar resorption," also known as "progressive condylar resorption," is described as a dysfunctional remodeling of the TMJ manifested by morphologic change, decreased ramal height, progressive mandibular retrusion in the adult, or decreased mandibular growth in the juvenile. This article discusses the diagnosis and management of osteoarthritic TMJ disorders and idiopathic condylar resorption.

  18. Ion transporters involved in acidification of the resorption lacuna in osteoclasts

    DEFF Research Database (Denmark)

    Henriksen, Kim; Sørensen, Mette G; Jensen, Vicki K;

    2008-01-01

    is currently not well understood. We used a battery of ion channel inhibitors, human osteoclasts, and their subcellular compartments to perform an unbiased analysis of the importance of the different ion transporters for acidification of the resorption lacuna in osteoclasts. CD14(+) monocytes from human...... peripheral blood were isolated, and mature osteoclasts were generated using RANKL and M-CSF. The human osteoclasts were (1) used for acridine orange assays for evaluation of lysosomal acidification, (2) used for bone resorption assays, (3) used for generation of osteoclasts membranes for acid influx...

  19. Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells.

    Science.gov (United States)

    Florencio-Silva, Rinaldo; Sasso, Gisela Rodrigues da Silva; Sasso-Cerri, Estela; Simões, Manuel Jesus; Cerri, Paulo Sérgio

    2015-01-01

    Bone tissue is continuously remodeled through the concerted actions of bone cells, which include bone resorption by osteoclasts and bone formation by osteoblasts, whereas osteocytes act as mechanosensors and orchestrators of the bone remodeling process. This process is under the control of local (e.g., growth factors and cytokines) and systemic (e.g., calcitonin and estrogens) factors that all together contribute for bone homeostasis. An imbalance between bone resorption and formation can result in bone diseases including osteoporosis. Recently, it has been recognized that, during bone remodeling, there are an intricate communication among bone cells. For instance, the coupling from bone resorption to bone formation is achieved by interaction between osteoclasts and osteoblasts. Moreover, osteocytes produce factors that influence osteoblast and osteoclast activities, whereas osteocyte apoptosis is followed by osteoclastic bone resorption. The increasing knowledge about the structure and functions of bone cells contributed to a better understanding of bone biology. It has been suggested that there is a complex communication between bone cells and other organs, indicating the dynamic nature of bone tissue. In this review, we discuss the current data about the structure and functions of bone cells and the factors that influence bone remodeling.

  20. Clinical application of site preservation in posterior area in order to prevent alveolar bone resorption after tooth extraction%应用位点保存技术预防拔牙后牙槽骨吸收的临床疗效观察

    Institute of Scientific and Technical Information of China (English)

    李景辉; 杨瑛; 张方明

    2016-01-01

    目的:观察和评价应用位点保存技术预防拔牙后牙槽骨吸收的临床疗效。方法选取需要拔除下颌磨牙的患者40例,随机分为两组。实验组20例患者拔牙后即刻在拔牙窝内植入 Bio - Oss骨粉,创口表面覆盖 Bio -Gide胶原膜,对照组20例患者拔牙后进行常规处理。定期复查观察两组患者拔牙窝愈合情况,于拔牙后即刻与拔牙后6个月拍摄锥形束 CT(CBCT),观察和测量牙槽骨垂直向吸收量、牙槽骨高度与宽度、骨密度和新骨轮廓的变化,评价位点保存的临床效果。结果拔牙后6个月实验组牙槽骨垂直向吸收量明显小于对照组;实验组骨密度、新骨轮廓明显优于对照组,两组之间具有统计学差异( P <0.05)。CBCT 测量统计学分析后证实两组间牙槽骨高度与宽度的变化具有显著性差异( P <0.05)。结论位点保存技术可以有效减少因拔牙而造成的牙槽骨吸收,很好地维持拔牙位点的骨量,从而为后期的种植牙修复提供良好的位点条件,值得临床推广。%Objective To observe the clinical effect of site preservation in posterior area in order to prevent alveolar bone resorption after tooth extraction. Methods Forty patients with posterior sick teeth were selected for this study,and they were randomly divided into two groups, 20 patients in trial group were implanted with Bio - Oss in the alveolar socket immediately after tooth extraction,the wound surface covered by Bio- Gide collagen membrane,and the tooth extraction in 20 patients of control group had been performed by conventional treatment. The results of patients in these two groups were observed The changes in alveolar bone density,height,width and new bone contour were observed by CBCTscan-ning in patients of these 2 groups after 6 months. Results In comparison with these two groups,new bone contour and bone density in patients of trial group were significantly

  1. Repair of microdamage in osteonal cortical bone adjacent to bone screw.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available Up to date, little is known about the repair mode of microdamage in osteonal cortical bone resulting from bone screw implantation. In this study, self-tapping titanium cortical bone screws were inserted into the tibial diaphyses of 24 adult male rabbits. The animals were sacrificed at 1 day, 2 weeks, 1 month and 2 months after surgery. Histomorphometric measurement and confocal microscopy were performed on basic fuchsin stained bone sections to examine the morphological characteristics of microdamage, bone resorption activity and spatial relationship between microdamage and bone resorption. Diffuse and linear cracks were coexisted in peri-screw bone. Intracortical bone resorption was significantly increased 2 weeks after screw installation and reach to the maximum at 1 month. There was no significant difference in bone resorption between 1-month and 2-months groups. Microdamage was significantly decreased within 1 month after surgery. Bone resorption was predisposed to occur in the region of <100 µm from the bone-screw interface, where had extensive diffuse damage mixed with linear cracks. Different patterns of resorption cavities appeared in peri-screw bone. These data suggest that 1 the complex microdamage composed of diffuse damage and linear cracks is a strong stimulator for initiating targeted bone remodeling; 2 bone resorption activities taking place on the surfaces of differently oriented Haversian and Volkmann canals work in a team for the repair of extensive microdamage; 3 targeted bone remodeling is a short-term reaction to microdamage and thereby it may not be able to remove all microdamage resulting from bone screw insertion.

  2. Apical root resorption in orthodontically treated adults.

    Science.gov (United States)

    Baumrind, S; Korn, E L; Boyd, R L

    1996-09-01

    This study analyzed the relationship in orthodontically treated adults between upper central incisor displacement measured on lateral cephalograms and apical root resorption measured on anterior periapical x-ray films. A multiple linear regression examined incisor displacements in four directions (retraction, advancement, intrusion, and extrusion) as independent variables, attempting to account for observed differences in the dependent variable, resorption. Mean apical resorption was 1.36 mm (sd +/- 1.46, n = 73). Mean horizontal displacement of the apex was -0.83 mm (sd +/- 1.74, n = 67); mean vertical displacement was 0.19 mm (sd +/- 1.48, n = 67). The regression coefficients for the intercept and for retraction were highly significant; those for extrusion, intrusion, and advancement were not. At the 95% confidence level, an average of 0.99 mm (se = +/- 0.34) of resorption was implied in the absence of root displacement and an average of 0.49 mm (se = +/- 0.14) of resorption was implied per millimeter of retraction. R2 for all four directional displacement variables (DDVs) taken together was only 0.20, which implied that only a relatively small portion of the observed apical resorption could be accounted for by tooth displacement alone. In a secondary set of univariate analyses, the associations between apical resorption and each of 14 additional treatment-related variables were examined. Only Gender, Elapsed Time, and Total Apical Displacement displayed statistically significant associations with apical resorption. Additional multiple regressions were then performed in which the data for each of these three statistically significant variables were considered separately, with the data for the four directional displacement variables. The addition of information on Elapsed Time or Total Apical Displacement did not explain a significant additional portion of the variability in apical resorption. On the other hand, the addition of information on Gender to the

  3. Melatonin: Bone Metabolism in Oral Cavity

    Directory of Open Access Journals (Sweden)

    Fanny López-Martínez

    2012-01-01

    Full Text Available Throughout life, bone tissue undergoes a continuous process of resorption and formation. Melatonin, with its antioxidant properties and its ability to detoxify free radicals, as suggested by Conconi et al. (2000 may interfere in the osteoclast function and thereby inhibit bone resorption, as suggested by Schroeder et al. (1981. Inhibition of bone resorption may be enhanced by a reaction of indoleamine in osteoclastogenesis. That it has been observed melatonin, at pharmacological doses, decrease bone mass resorption by suppressing through down regulation of the RANK-L, as suggested by Penarrocha Diago et al. (2005 and Steflik et al. (1994. These data point an osteogenic effect towards that may be of melatonin of clinical importance, as it could be used as a therapeutic agent in situations in which would be advantageous bone formation, such as in the treatment of fractures or osteoporosis or their use as, a bioactive surface on implant as suggested by Lissoni et al. (1991.

  4. Effect of Nanocrystalline Hydroxyapatite Socket Preservation on Orthodontically Induced Inflammatory Root Resorption

    Science.gov (United States)

    Seifi, Massoud; Arayesh, Ali; Shamloo, Nafise; Hamedi, Roya

    2015-01-01

    Objective Orthodontically induced inflammatory root resorption (OIIRR) is considered to be an important sequel associated with orthodontic tooth movement (OTM). OTM after Socket preservation enhances the periodontal condition before orthodontic space closure. The purpose of this study is to investigate the histologic effects of NanoBone®, a new highly nonsintered porous nano-crystalline hydroxyapatite bone on root resorption following OTM. Materials and Methods This experimental study was conducted on four male dogs. In each dog, four defects were created at the mesial aspects of the maxillary and mandibular first premolars. The defects were filled with NanoBone®. We used the NiTi closed coil for mesial movement of the first premolar tooth. When the experimental teeth moved approximately halfway into the defects, after two months, the animals were sacrificed and we harvested the area of interest. The first premolar root and adjacent tissues were histologically evaluated. The three-way ANOVA statistical test was used for comparison. Results The mean root resorption in the synthetic bone substitute group was 22.87 ± 11.25×10-4mm2 in the maxilla and 21.41 ± 11.25×10-4mm2 in the mandible. Statistically, there was no significant difference compared to the control group (p>0.05). Conclusion The use of a substitution graft in the nano particle has some positive effects in accessing healthy periodontal tissue following orthodontic procedures without significant influence on root resorption (RR). Histological evaluation in the present study showed osteoblastic activity and remodeling environment of nanoparticles in NanoBone®. PMID:25685742

  5. Bone Biochemistry on the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Heer, Martina; Zwart, Sara R.

    2016-01-01

    Bone biochemical measures provide valuable insight into the nature and time course of microgravity effects on bone during space flight, where imaging technology cannot be employed. Increased bone resorption is a hallmark of space flight, while markers of bone formation are typically unchanged or decreased. Recent studies (after the deployment to ISS of the advanced resistive exercise device, ARED), have documented that astronauts with good nutritional intake (e.g., maintenance of body mass), good vitamin D status, and exercise maintained bone mineral density. These data are encouraging, but crewmembers exercising on the ARED do have alterations in bone biochemistry, specifically, bone resorption is still increased above preflight levels, but bone formation is also significantly increased. While this bone remodeling raises questions about the strength of the resulting bone, however documents beneficial effects of nutrition and exercise in counteracting bone loss of space flight.

  6. Apical root resorption after orthodontic treatment -- a retrospective study.

    Science.gov (United States)

    Apajalahti, Satu; Peltola, Jaakko Sakari

    2007-08-01

    The purpose of the study was to compare the incidence and severity of apical root resorption in patients treated with different orthodontic appliances and to evaluate the effect of treatment duration on the degree of apical root resorption. A further aim was to analyse the degree of apical root resorption in different tooth groups in patients presenting with root resorption. The sample consisted of 625 patients (269 males, 356 females) aged 8-16 years at the beginning of treatment. Active removable plates and fixed appliances were used most frequently. Following exclusion of poor quality radiographs, the final sample included 601 patients (348 females, 253 males). Root resorption in all tooth groups, except third molars, was evaluated from pre- and post-treatment panoramic radiographs. The correlation of root resorption with treatment modality and duration was studied using multinomial logistic regression analysis. Of the tooth groups, maxillary incisors showed apical root resorption most frequently, followed by the mandibular incisors. Root resorption was significantly correlated with fixed appliance treatment (P resorption. The mean duration of treatment in patients without root resorption was 1.5 years, whereas in those with severe resorption was 2.3 years. The most severe resorption was seen in the maxillary incisors and premolars. It is concluded that with a long duration of fixed appliance treatment, the risk of severe resorption increases. In patients where treatment is prolonged, a 6-month radiographic follow-up is recommended.

  7. The Effect of Ovariectomy and Orchiectomy on Orthodontic Tooth Movement and Root Resorption in Wistar Rats

    Science.gov (United States)

    Seifi, Massoud; Ezzati, Baharak; Saedi, Sara; Hedayati, Mehdi

    2015-01-01

    Statement of the Problem Root resorption (RR) after orthodontic tooth movement (OTM) is known as a multifactorial complication of orthodontic treatments. Hormonal deficiencies and their effect on bone turnover are reported to have influences on the rate of tooth movement and root resorption. Purpose This study was designed to evaluate the effect of female and male steroid sex hormones on tooth movement and root resorption. Materials and Method Orthodontic appliances were placed on the right maxillary first molars of 10 ovariectomized female and 10 orchiectomized male Wistar rats as experimental groups and 10 female and 10 male healthy Wistar rats as control groups. NiTi closed-coil springs (9mm, Medium, 011"×.030", Ortho Technology®; Tampa, Florida) were placed between the right incisors and the first right maxillary molars to induce tipping movement in the first molars with the application of a 60g force. After 21 days, the rats were sacrificed and tooth movement was measured by using a digital caliper (Guanglu, China). Orthodontic induced root resorption (OIRR) was assessed by histomorphometric analysis after hematoxylin and eosin staining of sections of the mesial root. Results The rate of tooth movement was significantly higher in all female rats, with the root resorption being lower in the experimental group. The rate of tooth movement in experimental male rats was significantly higher than the control group (p= 0.001) and the rate of root resorption was significantly lower in the experimental group (p= 0.001). Conclusion It seems that alterations in plasma levels of estrogen, progesterone, and testosterone hormones can influence the rate of OTM and RR. The acceleration in tooth movement increased OTM and decreased RR. PMID:26636117

  8. Thyroxine Induced Resorption of Xenopus Laevis Tail Tissue in Vitro.

    Science.gov (United States)

    Scadding, Steven R.

    1984-01-01

    A simple method of studying thyroxine-induced resorption of tadpole tails in vitro is described. This procedure demonstrates that resorption is dependent on thyroxine and requires protein synthesis. It introduces students to the use of tissue culture methods. (Author)

  9. Effects of Tai Ji Exercise on Bone Structure and Function

    Institute of Scientific and Technical Information of China (English)

    Xu Hong; David Lawson

    2005-01-01

    To evaluated the effects of the 24 movements Tai Ji exercise on bone structure and function. Broadband Ultrsonic Attenuation (BUA) and velocity of sound (VOS), bone formation marker Osteocalcin (OSTN) and bone resorption markers urinary Pyridum crosslinks (PYR and D-PYR) were studied before and after four months of Tai Ji exercise. Improved bone structure and increased bone density in menopausal women were reflected by BUA results. The increased BUA appears to be associated with increased bone formation rather than decreased bone resorption.

  10. External cervical resorption: diagnostic and treatment tips

    Science.gov (United States)

    Consolaro, Alberto

    2016-01-01

    ABSTRACT External cervical resorption is caused, almost exclusively, by dental trauma - especially those characterized by concussion - and is a dental disease to be diagnosed and treated accurately by endodontists. However, the vast majority of the cases is initially diagnosed by an orthodontist, due to the imaging possibilities in standardized documentations. Among the causes of external cervical resorption, it is common to mistakenly attribute it to orthodontic treatment, traumatic occlusion or even to chronic inflammatory periodontal disease. External cervical resorption is associated to dental trauma in several situations mentioned in this paper. In old cases, and eventually still nowadays, it may have been induced by internal tooth bleaching, which is increasingly less frequent in endodontically treated teeth. There are some tips to be followed and some care that must be taken during the diagnosis and treatment of external cervical resorption clinical cases. The present study lists foundations that will allow the professional to perform safely and accurately in each specific case. Some of these tips and care measures are of orthodontic nature. PMID:27901225

  11. Root resorption after orthodontic intrusion and extrusion:.

    NARCIS (Netherlands)

    Han, G.; Huang, S.; Hoff, J.W. Von den; Zeng, X.; Kuijpers-Jagtman, A.M.

    2005-01-01

    The aim of this investigation was to compare root resorption in the same individual after application of continuous intrusive and extrusive forces. In nine patients (mean age 15.3 years), the maxillary first premolars were randomly intruded or extruded with a continuous force of 100 cN for eight wee

  12. External cervical resorption: diagnostic and treatment tips

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    Full Text Available ABSTRACT External cervical resorption is caused, almost exclusively, by dental trauma - especially those characterized by concussion - and is a dental disease to be diagnosed and treated accurately by endodontists. However, the vast majority of the cases is initially diagnosed by an orthodontist, due to the imaging possibilities in standardized documentations. Among the causes of external cervical resorption, it is common to mistakenly attribute it to orthodontic treatment, traumatic occlusion or even to chronic inflammatory periodontal disease. External cervical resorption is associated to dental trauma in several situations mentioned in this paper. In old cases, and eventually still nowadays, it may have been induced by internal tooth bleaching, which is increasingly less frequent in endodontically treated teeth. There are some tips to be followed and some care that must be taken during the diagnosis and treatment of external cervical resorption clinical cases. The present study lists foundations that will allow the professional to perform safely and accurately in each specific case. Some of these tips and care measures are of orthodontic nature.

  13. Internal root resorption in the maxillary central incisor

    OpenAIRE

    2010-01-01

    Introduction: Internal root resorption is a chronic inflammatory process initiated within the pulp space with the loss of dentin. The clastic cells present in the pulp tissue trigger a progressive resorption phenomenon. Case report and conclusion: This paper reports a clinical case of an internal root resorption in the permanent central incisor, at the middle third of the root canal. Because it is asymptomatic,internal root resorption needs an early diagnosis in order to institute the endodon...

  14. Inhibition of TNF-α Reverses the Pathological Resorption Pit Profile of Osteoclasts from Patients with Acute Charcot Osteoarthropathy

    Directory of Open Access Journals (Sweden)

    Nina L. Petrova

    2015-01-01

    Full Text Available We hypothesised that tumour necrosis factor-α (TNF-α may enhance receptor activator of nuclear factor-κβ ligand- (RANKL- mediated osteoclastogenesis in acute Charcot osteoarthropathy. Peripheral blood monocytes were isolated from 10 acute Charcot patients, 8 diabetic patients, and 9 healthy control subjects and cultured in vitro on plastic and bone discs. Osteoclast formation and resorption were assessed after treatment with (1 macrophage-colony stimulating factor (M-CSF and RANKL and (2 M-CSF, RANKL, and neutralising antibody to TNF-α (anti-TNF-α. Resorption was measured on the surface of bone discs by image analysis and under the surface using surface profilometry. Although osteoclast formation was similar in M-CSF + RANKL-treated cultures between the groups (p>0.05, there was a significant increase in the area of resorption on the surface (p<0.01 and under the surface (p<0.01 in Charcot patients compared with diabetic patients and control subjects. The addition of anti-TNF-α resulted in a significant reduction in the area of resorption on the surface (p<0.05 and under the surface (p<0.05 only in Charcot patients as well as a normalisation of the aberrant erosion profile. We conclude that TNF-α modulates RANKL-mediated osteoclastic resorption in vitro in patients with acute Charcot osteoarthropathy.

  15. Radiographic evaluation of apical root resorption following fixed orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Sina Haghanifar

    2012-01-01

    Full Text Available Background and Aims: Apical root resorption is an adverse side effect of fixed orthodontic treatment which cannot be repaired. The aim of this study was to use panoramic radiographs to compare the root resorption before and after the orthodontic treatment with standard edgewise .018 appliance.Materials and Methods: The before and after treatment panoramic views of sixty-three patients needed fixed orthodontic treatment included 1520 teeth were categorized into 3 Grades (G0: without resorption, G1: mild resorption with blunt roots or ≤ 1/4 of root length, G2: moderate to severe resorption or > 1/4 to 1/2 of root length. Relationship between root resorption and sex and treatment duration was analyzed with Mann-whitney and Spearman's correlation coefficient, respectively.Results: The findings showed that 345 teeth were categorized as Grade 1. Grade 2 of root resorption was not found in this study. The highest amount of root resorption was recorded for the mandibular lateral incisor. In both gender, the root resorption of the mandible was more than that of the maxilla. The males showed significantly higher rate of resorption than the females (P0.05.Conclusion: The mandible and male patients showed higher amount of root resorption. In addition, root resorption was not related to the treatment duration and the side of the jaws.

  16. Regional Aggressive Root Resorption Caused by Neuronal Virus Infection

    Directory of Open Access Journals (Sweden)

    Inger Kjær

    2012-01-01

    Full Text Available During orthodontic treatment, root resorption can occur unexplainably. No clear distinction has been made between resorption located within specific regions and resorption occurring generally in the dentition. The purpose is to present cases with idiopathic (of unknown origin root resorption occurring regionally. Two cases of female patients, 26 and 28 years old, referred with aggressive root resorption were investigated clinically and radiographically. Anamnestic information revealed severe virus diseases during childhood, meningitis in one case and whooping cough in the other. One of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface against resorption. Therefore, the normal nerve pattern is important for diagnostics and for predicting the course of severe unexpected root resorption.

  17. Tooth resorption in cats: contribution of vitamin D and inflammation

    NARCIS (Netherlands)

    Vrieling, H.E.

    2010-01-01

    Tooth resorption in cats Tooth resorption affecting several teeth is a painful disease with a prevalence of up to 75% in household cats and is often accompanied by periodontitis. Tooth resorption is caused by an increased number and activity of tooth-resorbing odontoclasts, cells that share function

  18. ASSESSMENT OF ROOT RESORPTION DEGREE OF INCISORS AFTER ORTHODONTIC TREATMENT IN ADULTS

    Directory of Open Access Journals (Sweden)

    I. Luchian

    2012-03-01

    Full Text Available The main iatrogenic effects associated with orthodontic treatment refer to: influence of orthodontic rings on the periodontal tissue; gum retractions; the effect of the orthodontic treatment on dental root (root resorption; the effect of the orthodontic treatment on alveolar bone height; mobility and pain associated with orthodontic treatment. AIM of the study: To assess the degree of root resorption of incisors, after orthodontic treatment, on a group of 48 adults with dental-maxillary abnormalities. Materials and method: The study included 48 young adult patients, 35 women and 13 men aged 18 to 30 years, who had received fixed orthodontic treatment. To assess the degree of root resorption (changes at root level and apical contour length, apical radiographies were taken in the maxillary incisors and jaw both at the beginning and end of the orthodontic treatment. Results: Out of the 239 incisors examined at the beginning of orthodontic treatment, 163 showed code 0, meaning 88.1%, and 50 showed a slight squash apex (code 1, respectively 10.9%. Only 1% of all incisors assessed presented mild and severe root resorption. Conclusions: The results of the study show that, generally, an adult orthodontic treatment, applied for functional and aesthetic objectives, may have clinically acceptable iatrogenic effects.

  19. Effect of gingival fibroblasts and ultrasound on dogs' root resorption during orthodontic treatment

    Science.gov (United States)

    Crossman, Jacqueline; Hassan, Ali H; Saleem, Ali; Felemban, Nayef; Aldaghreer, Saleh; Fawzi, Elham; Farid, Mamdouh; Abdel-Ghaffar, Khaled; Gargoum, Ausama; El-Bialy, Tarek

    2017-01-01

    Objectives: To investigate the effect of using osteogenic induced gingival fibroblasts (OIGFs) and low intensity pulsed ultrasound (LIPUS) on root resorption lacunae volume and cementum thickness in beagle dogs that received orthodontic tooth movement. Materials and Methods: Seven beagle dogs were used, from which gingival cells (GCs) were obtained and were induced osteogenically to produce OIGFs. Each third and fourth premolar was randomly assigned to one of the five groups, namely, LIPUS, OIGFs, bone morphogenetic protein-2 (BMP-2), OIGFs + LIPUS, and control. All groups received 4 weeks of bodily tooth movement, then LIPUS-treated groups received LIPUS for 20 min/day for 4 weeks, and OIGFs groups received an injection of OIGFs near the root apex. Microcomputed tomography analysis was used to calculate root resorption lacunae volume and histomorphometric analysis was performed to measure the cementum thickness of each root at 3 root levels on compression and tension sides. Results: There was no significant difference in resorption volume between the treatment groups. OIGFs + LIPUS increased cementum thickness (P > 0.05) in third premolars near the apex, and LIPUS increased cementum thickness (P > 0.05) in fourth premolars near the apex. Furthermore, BMP2 increased cementum thickness at the coronal third at the compression side. Conclusion: OIGFs, LIPUS, and BMP-2 can be potential treatments for orthodontically induced root resorption, however, improvements in experimental design and treatment parameters are required to further investigate these repair modalities. PMID:28197400

  20. Strontium ranelate improved tooth anchorage and reduced root resorption in orthodontic treatment of rats.

    Science.gov (United States)

    Kirschneck, Christian; Wolf, Michael; Reicheneder, Claudia; Wahlmann, Ulrich; Proff, Peter; Roemer, Piero

    2014-12-05

    The anchorage mechanisms currently used in orthodontic treatment have various disadvantages. The objective of this study was to determine the applicability of the osteoporosis medication strontium ranelate in pharmacologically induced orthodontic tooth anchorage. In 48 male Wistar rats, a constant orthodontic force of 0.25 N was reciprocally applied to the upper first molar and the incisors by means of a Sentalloy(®) closed coil spring for two to four weeks. 50% of the animals received strontium ranelate at a daily oral dosage of 900 mg per kilogramme of body weight. Bioavailability was determined by blood analyses. The extent of tooth movement was measured both optometrically and cephalometrically (CBCT). Relative alveolar gene expression of osteoclastic markers and OPG-RANKL was assessed by qRT-PCR and root resorption area and osteoclastic activity were determined in TRAP-stained histologic sections of the alveolar process. Compared to controls, the animals treated with strontium ranelate showed up to 40% less tooth movement after four weeks of orthodontic treatment. Gene expression and histologic analyses showed significantly less osteoclastic activity and a significantly smaller root resorption area. Blood analyses confirmed sufficient bioavailability of strontium ranelate. Because of its pharmacologic effects on bone metabolism, strontium ranelate significantly reduced tooth movement and root resorption in orthodontic treatment of rats. Strontium ranelate may be a viable agent for inducing tooth anchorage and reducing undesired root resorption in orthodontic treatment. Patients under medication of strontium ranelate have to expect prolonged orthodontic treatment times.

  1. Novel use of a Dektak 150 surface profiler unmasks differences in resorption pit profiles between control and Charcot patient osteoclasts.

    Science.gov (United States)

    Petrova, Nina L; Petrov, Peter K; Edmonds, Michael E; Shanahan, Catherine M

    2014-04-01

    We hypothesized that newly formed osteoclasts from patients with acute Charcot osteoarthropathy can resorb surfaces of bone more extensively compared with controls. Peripheral blood monocytes, isolated from eight Charcot patients and nine controls, were cultured in vitro on 24-well plates and bovine bone discs in duplicate with macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κβ ligand (RANKL). Osteoclast formation was assessed by tartrate-resistant acid phosphatase staining (TRAcP) at day 17. Resorption was measured at day 21 after toluidine blue staining by two methods: (1) area of resorption at the surface by image analysis (%) and (2) area of resorption under the surface (μm(2)) measured by a Dektak 150 Surface Profiler. Ten 1,000 μm-long scans were performed per disc. Pits were classified as unidented, bidented, and multidented according to their shape. Although the number of newly formed TRAcP positive multinucleated cells (>3 nuclei) was similar in M-CSF + RANKL-treated cultures between controls and Charcot patients, the latter exhibited increased resorbing activity. The area of resorption on the surface by image analysis was significantly greater in Charcot patients compared with controls (21.1 % [14.5-26.2] vs. 40.8 % [35.4-46.0], median [25-75th percentile], p Charcot patients pits were deeper and wider and more frequently presented as multidented pits. This application of the Dektak 150 Surface Profiler revealed novel differences in resorption pit profile from osteoclasts derived from Charcot patients compared with controls. Resorption in Charcot patients was mediated by highly aggressive newly formed osteoclasts from monocytes eroding large and deep areas of bone.

  2. Regional aggressive root resorption caused by neuronal virus infection

    DEFF Research Database (Denmark)

    Kjær, Inger; Strøm, Carsten; Worsaae, Nils

    2012-01-01

    of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process...... stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface...

  3. Stoichiometric patterns in foliar nutrient resorption across multiple scales

    Science.gov (United States)

    Reed, Sasha C.; Townsend, Alan R.; Davidson, Eric A.; Cleveland, Cory C.

    2012-01-01

    *Nutrient resorption is a fundamental process through which plants withdraw nutrients from leaves before abscission. Nutrient resorption patterns have the potential to reflect gradients in plant nutrient limitation and to affect a suite of terrestrial ecosystem functions. *Here, we used a stoichiometric approach to assess patterns in foliar resorption at a variety of scales, specifically exploring how N : P resorption ratios relate to presumed variation in N and/or P limitation and possible relationships between N : P resorption ratios and soil nutrient availability. *N : P resorption ratios varied significantly at the global scale, increasing with latitude and decreasing with mean annual temperature and precipitation. In general, tropical sites (absolute latitudes resorption ratios of resorption ratios. Resorption ratios also varied with forest age along an Amazonian forest regeneration chronosequence and among species in a diverse Costa Rican rain forest. *These results suggest that variations in N : P resorption stoichiometry offer insight into nutrient cycling and limitation at a variety of spatial scales, complementing other metrics of plant nutrient biogeochemistry. The extent to which the stoichiometric flexibility of resorption will help regulate terrestrial responses to global change merits further investigation.

  4. Role of purinergic receptor polymorphisms in human bone

    DEFF Research Database (Denmark)

    Wesselius, Anke; Bours, Martijn J L; Agrawal, Ankita;

    2011-01-01

    receptor subtypes have been identified on bone cells. Several cellular functions in bone tissue are coupled to P2-receptor activation, including bone resorption, cytokine release, apoptosis, bone formation, and mineral deposition. Furthermore, ATP release and P2 purinergic signalling is a key pathway...

  5. Etiology and sequelae of root resorption.

    Science.gov (United States)

    Vlaskalic, V; Boyd, R L; Baumrind, S

    1998-06-01

    This article reviews the current status of investigation into apical root resorption within the context of orthodontic treatment. Treatment and patient factors that have traditionally been investigated are discussed, along with the results of current research in this area. The need for rethinking traditional research strategies in the quest for identifying both control and causative mechanisms is explored. Finally, proposals for key areas of future interest are highlighted.

  6. Donepezil prevents RANK-induced bone loss via inhibition of osteoclast differentiation by downregulating acetylcholinesterase

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    Tsuyoshi Sato

    2015-09-01

    Conclusions: AChE promotes osteoclast differentiation in vitro. Donepezil inhibits osteoclast function in vitro and prevents bone loss by suppressing bone resorption in vivo, suggesting the possibility that donepezil reduces fracture risk in patients with Alzheimer's disease.

  7. Passive and active in vitro resorption of calcium and magnesium phosphate cements by osteoclastic cells.

    Science.gov (United States)

    Grossardt, Christian; Ewald, Andrea; Grover, Liam M; Barralet, Jake E; Gbureck, Uwe

    2010-12-01

    Biocements are clinically applied materials for bone replacement in non-load-bearing defects. Depending on their final composition, cements can be either resorbed or remain stable at the implantation site. Degradation can occur by two different mechanisms, by simple dissolution (passive) or after osteoclastic bone remodeling (active). This study investigated both the passive and active in vitro resorption behavior of brushite (CaHPO₄ · 2H₂O), monetite (CaHPO₄), calcium-deficient hydroxyapatite (CDHA; Ca₉(PO₄)₅HPO₄OH), and struvite (MgNH₄PO₄ · 6H₂O) cements. Passive resorption was measured by incubating the cement samples in a cell culture medium, whereas active resorption was determined during the surface culture of multinuclear osteoclastic cells derived from RAW 264.7 macrophages. Osteoclast formation was confirmed by showing tartrate resistant acid phosphatase (TRAP) activity on CDHA, brushite, and monetite surfaces, as well as by measuring calcitonin receptor (CT-R) expression as an osteoclast-specific protein by Western blot analysis for struvite ceramics. An absence of passive degradation and only marginally active degradation of struvite cement was the most degradable with a passive (active) release of 9.26 (2.92) Mg²+ ions and a total weight loss of 4.7% over 13 days of the study.

  8. The Effect of An Angiogenic Cytokine on Orthodontically Induced Inflammatory Root Resorption

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    Massoud Seifi

    2016-07-01

    Full Text Available Objective Orthodontically induced inflammatory root resorption (OIIRR is an undesirable sequel of tooth movement after sterile necrosis that takes place in periodontal ligament due to blockage of blood vessels following exertion of orthodontic force. This study sought to assess the effect of an angiogenic cytokine on OIIRR in rat model. Materials and Methods In this experimental animal study, 50 rats were randomly divided into 5 groups of 10 each: E10, E100 and E1000 receiving an injection of 10, 100 and 1000 ng of basic fibroblast growth factor (bFGF, respectively, positive control group (CP receiving an orthodontic appliance and injection of phosphate buffered saline (PBS and the negative control group (CN receiving only the anesthetic agent. A nickel titanium coil spring was placed between the first molar and the incisor on the right side of maxilla. Twenty-one days later, the rats were sacrificed. Histopathological sections were made to assess the number and area of resorption lacunae, number of blood vessels, osteoclasts and Howship’s lacunae. Data were statistically analyzed using ANOVA and Tukey’s honest significant difference (HSD test. Results Number of resorption lacunae and area of resorption lacunae in E1000 (0.97 ± 0.80 and 1. 27 ± 0.01×10-3, respectively were significantly lower than in CP (4.17 ± 0.90 and 2.77 ± 0.01×10-3, respectively, P=0.000. Number of blood vessels, osteoclasts and Howship’s lacunae were significantly higher in E1000 compared to CP (P<0.05. Conclusion Tooth movement as the outcome of bone remodeling is concomitant with the formation of sterile necrosis in the periodontal ligament following blocked blood supply. Thus, bFGF can significantly decrease the risk of root resorption by providing more oxygen and angiogenesis.

  9. Oxytocin and bone

    Science.gov (United States)

    Sun, Li; Zaidi, Mone; Zallone, Alberta

    2014-01-01

    One of the most meaningful results recently achieved in bone research has been to reveal that the pituitary hormones have profound effect on bone, so that the pituitary-bone axis has become one of the major topics in skeletal physiology. Here, we discuss the relevant evidence about the posterior pituitary hormone oxytocin (OT), previously thought to exclusively regulate parturition and breastfeeding, which has recently been established to directly regulate bone mass. Both osteoblasts and osteoclasts express OT receptors (OTR), whose stimulation enhances bone mass. Consistent with this, mice deficient in OT or OTR display profoundly impaired bone formation. In contrast, bone resorption remains unaffected in OT deficiency because, even while OT stimulates the genesis of osteoclasts, it inhibits their resorptive function. Furthermore, in addition to its origin from the pituitary, OT is also produced by bone marrow osteoblasts acting as paracrine-autocrine regulator of bone formation modulated by estrogens. In turn, the power of estrogen to increase bone mass is OTR-dependent. Therefore, OTR−/− mice injected with 17β-estradiol do not show any effects on bone formation parameters, while the same treatment increases bone mass in wild-type mice. These findings together provide evidence for an anabolic action of OT in regulating bone mass and suggest that bone marrow OT may enhance the bone-forming action of estrogen through an autocrine circuit. This established new physiological role for OT in the maintenance of skeletal integrity further suggests the potential use of this hormone for the treatment of osteoporosis. PMID:25209411

  10. Frequency of root resorption following trauma to permanent teeth.

    Science.gov (United States)

    Soares, Adriana J; Souza, Gustavo A; Pereira, Andrea C; Vargas-Neto, Julio; Zaia, Alexandre A; Silva, Emmanuel J N L

    2015-06-01

    This retrospective study evaluated the frequency of development of root resorption in dental trauma cases involving supporting tissue. For 249 traumatized teeth of 125 patients aged between 7 and 51 years, we collected data on the gender and age of the patient, the teeth involved, the type of trauma, and the period between dental injury and initial examination. Radiographic parameters examined in relation to root resorption included the presence of inflammatory external root resorption, internal root resorption, replacement resorption, and canal calcification. Data were analyzed by chi-squared test, Fisher's exact test, and mult iple logistic regression (P resorption (P = 0.0199), as well as the type of injury (P = 0.0406). Furthermore, external resorption was most frequently associated with intrusive luxation (92.8%), followed by avulsion (89.0%), lateral luxation (80.2%), and extrusive luxation (77.4%). Among the types of dental injury, replacement resorption was observed more frequently in cases of avulsion (87.2%). The only factor that was significantly associated with this type of resorption was the type of injury (P resorption is observed more frequently and its risk of development is higher in cases of severe trauma, especially avulsion and intrusive luxation.

  11. Investigations into Changes in Bone Turnover with Acute, Weight-Bearing Exercise in Healthy, Young Men

    Science.gov (United States)

    2009-10-01

    after the menopause . Subsequently, in the newly increased number of resorption spaces, bone formation occurs that is reflected by an increase in...specific BTM, new insights into the acute effects of exercise on bone resorption and formation are possible. 1.4 Nutrition , energy availability and...normal bone metabolism While the importance of appropriate nutrition in maintaining normal bone turnover has long been recognised, it is only with the

  12. Exploring the Bone Proteome to Help Explain Altered Bone Remodeling and Preservation of Bone Architecture and Strength in Hibernating Marmots.

    Science.gov (United States)

    Doherty, Alison H; Roteliuk, Danielle M; Gookin, Sara E; McGrew, Ashley K; Broccardo, Carolyn J; Condon, Keith W; Prenni, Jessica E; Wojda, Samantha J; Florant, Gregory L; Donahue, Seth W

    2016-01-01

    Periods of physical inactivity increase bone resorption and cause bone loss and increased fracture risk. However, hibernating bears, marmots, and woodchucks maintain bone structure and strength, despite being physically inactive for prolonged periods annually. We tested the hypothesis that bone turnover rates would decrease and bone structural and mechanical properties would be preserved in hibernating marmots (Marmota flaviventris). Femurs and tibias were collected from marmots during hibernation and in the summer following hibernation. Bone remodeling was significantly altered in cortical and trabecular bone during hibernation with suppressed formation and no change in resorption, unlike the increased bone resorption that occurs during disuse in humans and other animals. Trabecular bone architecture and cortical bone geometrical and mechanical properties were not different between hibernating and active marmots, but bone marrow adiposity was significantly greater in hibernators. Of the 506 proteins identified in marmot bone, 40 were significantly different in abundance between active and hibernating marmots. Monoaglycerol lipase, which plays an important role in fatty acid metabolism and the endocannabinoid system, was 98-fold higher in hibernating marmots compared with summer marmots and may play a role in regulating the changes in bone and fat metabolism that occur during hibernation.

  13. Dehydroepiandrosterone indirectly inhibits human osteoclastic resorption via activating osteoblastic viability by the MAPK pathway

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-dong; TAO Min-fang; CHENG Wei-wei; LIU Xiao-hua; WAN Xiao-ping; KeMi Cui

    2012-01-01

    Background Dehydroepiandrosterone (DHEA) is widely known for its beneficial effect on postmenopausal osteoporosis,although the underlying mechanisms remain mainly unclear.In this study,we tried to determine the activation of mitogen-activated protein kinase signal pathways during DHEA treatment and the indirect role of osteoblasts (OBs) on osteoclasts under the DHEA treatment of postmenopausal osteoporosis.@@Methods Primary human OBs and osteoclast-like cells were cultured and,we pretreated OBs with or without U0126 (a highly selective inhibitor of both MEK1 and MEK2).The OBs were treated with DHEA.We then tested the effects of DHEA on human osteoblastic viability,osteoprotegerin production and the expression of phosphor-ERK1/2 (extracellular signal-regulated kinase).In the presence or absence of OBs,the function of osteoclastic resorption upon DHEA treatment was calculated.@@Results DHEA promoted the human osteoblastic proliferation and inhibited the osteoblastic apoptosis within the concentration range of 108-10-6 mol/L (P <0.05,P <0.01,respectively).Within the effective concentration range,the expression of phosphor-ERK1/2 and osteoprotegerin was increased by DHEA and blocked by U0126.In the presence of OBs,DHEA could significantly decrease the number and the area of bone resorption lacuna (P <0.05 and P <0.01,respectively).Without OBs,however,the effects of DHEA on the bone resorption lacuna were almost completely abolished.@@Conclusions DHEA could indirectly inhibit the human osteoclastic resorption through promoting the osteoblastic viability and osteoprotegerin production,which is mediated by mitogen-activated protein kinases signal pathway involving the phosphor-ERK1/2.

  14. Idiopathic internal resorption: Report of a case with unusual features

    Directory of Open Access Journals (Sweden)

    Santosh Hunasgi

    2012-01-01

    Full Text Available Tooth resorption can occur from the internal surface of a tooth or from the external surface of a tooth. Internal resorption is commonly termed to be "idiopathic" because of unknown cause. The aim is to report a case of idiopathic internal resorption showing unusual features. A 25-year-old female patient complains of mobility of tooth in right lower back tooth region since 2 months. Clinically, there was slight mobility in 48. Radiographically a resorptive area was seen in crown region of 48. The crown part was removed with gentle pressure using probe. A hollow crown with resorbed dentin and intact thin enamel was seen in gross specimen. A final diagnosis of idiopathic internal resorption was given. Early detection is essential for successful management of idiopathic internal resorption. This prevents further weakening of remaining tooth structure leading to crown or root perforations.

  15. Amelogenesis Imperfecta with Coronal Resorption: Report of Three Cases.

    Science.gov (United States)

    Bhatia, Shannu K; Hunter, M Lindsay; Ashley, Paul F

    2015-12-01

    Intracoronal resorption of the permanent dentition in cases of amelogenesis imperfecta (AI) is a rare finding which poses an added complication to the already complex management of this condition. This paper presents three cases of AI associated with delayed eruption of permanent teeth in which asymptomatic intracoronal resorption occurred. CPD/Clinical Relevance: This paper highlights the fact that teeth affected with amelogenesis imperfecta may undergo asymptomatic intracoronal resorption which is only identifiable radiographically.

  16. Biomarkers of bone and mineral metabolism following bone marrow transplantation.

    Science.gov (United States)

    Baek, Ki Hyun; Kang, Moo Il

    2009-01-01

    The loss of bone mass often occurs after patients undergo bone marrow transplantation (BMT). The rapid impairment of bone formation and the increase in bone resorption, as mirrored by the biochemical markers of bone turnover, might play a role in this bone loss, and especially during the immediate post-BMT period. The possible direct causes for this paradoxical uncoupling are exposure to immunosuppressants, hypogonadism, the changes of cytokines, the changes of the bone growth factors, and the damage to the osteoprogenitor cells because of myeloablative therapy. In this chapter, we discuss the general aspects of post-BMT bone loss with a peculiar focus on the remodeling imbalance of bone and its relation to the use of immunosuppressants and the changes of sex hormones, growth factors, and cytokines.

  17. Characteristics of alveolar bone associated with physiological movement of molar in mice: a histological and histochemical study.

    Science.gov (United States)

    Matsuda, Kie; Haga-Tsujimura, Maiko; Yoshie, Sumio; Shimomura-Kuroki, Junko

    2014-01-01

    Mouse molars undergo distal movement, during which new bone is formed at the mesial side of the tooth root whereas the preexisting bone is resorbed at the distal side of the root. However, there is little detailed information available regarding which of the bones that surround the tooth root are involved in physiological tooth movement. In the present study, we therefore aimed to investigate the precise morphological differences of the alveolar bone between the bone formation side of the tooth root, using routine histological procedures including silver impregnation, as well as by immunohistochemical analysis of alkaline phosphatase and tartrate-resistant acid phosphatase activity, and immunohistochemical analysis of the expression of the osteocyte markers dentin matrix protein 1, sclerostin, and fibroblast growth factor 23. Histochemical analysis indicated that bone formation by osteoblasts and bone resorption by osteoclasts occurred at the bone formation side and the bone resorption side, respectively. Osteocyte marker immunoreactivity of osteocytes at the surface of the bone close to the periodontal ligament differed at the bone formation and bone resorption sides. We also showed different specific features of osteocytic lacunar canalicular systems at the bone formation and bone resorption sides by using silver staining. This study suggests that the alveolar bone is different in the osteocyte nature between the bone formation side and the bone resorption side due to physiological distal movement of the mouse molar.

  18. Ossicular bone modeling in acute otitis media

    DEFF Research Database (Denmark)

    Salomonsen, Rasmus Lysholdt; Hermansson, Ann; Cayé-Thomasen, Per

    2010-01-01

    A number of middle ear diseases are associated with pathologic bone modeling, either formative or resorptive. As such, the pathogenesis of a sclerotic mastoid has been controversial for decades. Experimental studies on acute middle ear infection have shown progressive osteoneogenesis in the bone ...

  19. Bone is not essential for osteoclast activation.

    Directory of Open Access Journals (Sweden)

    Karen Fuller

    Full Text Available BACKGROUND: The mechanism whereby bone activates resorptive behavior in osteoclasts, the cells that resorb bone, is unknown. It is known that α(vβ(3 ligands are important, because blockade of α(vβ(3 receptor signaling inhibits bone resorption, but this might be through inhibition of adhesion or migration rather than resorption itself. Nor is it known whether α(vβ(3 ligands are sufficient for resorption the consensus is that bone mineral is essential for the recognition of bone as the substrate appropriate for resorption. METHODOLOGY/PRINCIPAL FINDINGS: Vitronectin- but not fibronectin-coated coverslips induced murine osteoclasts to secrete tartrate-resistant acid phosphatase, as they do on bone. Osteoclasts incubated on vitronectin, unlike fibronectin, formed podosome belts on glass coverslips, and these were modulated by resorption-regulating cytokines. Podosome belts formed on vitronectin-coated surfaces whether the substrates were rough or smooth, rigid or flexible. We developed a novel approach whereby the substrate-apposed surface of cells can be visualized in the scanning electron microscope. With this approach, supported by transmission electron microscopy, we found that osteoclasts on vitronectin-coated surfaces show ruffled borders and clear zones characteristic of resorbing osteoclasts. Ruffles were obscured by a film if cells were incubated in the cathepsin inhibitor E64, suggesting that removal of the film represents substrate-degrading behavior. Analogously, osteoclasts formed resorption-like trails on vitronectin-coated substrates. Like bone resorption, these trails were dependent upon resorbogenic cytokines and were inhibited by E64. Bone mineral induced actin rings and surface excavation only if first coated with vitronectin. Fibronectin could not substitute in any of these activities, despite enabling adhesion and cell spreading. CONCLUSIONS/SIGNIFICANCE: Our results show that ligands α(vβ(3 are not only necessary but

  20. Bone Metabolism on ISS Missions

    Science.gov (United States)

    Smith, S. M.; Heer, M. A.; Shackelford, L. C.; Zwart, S. R.

    2014-01-01

    Spaceflight-induced bone loss is associated with increased bone resorption (1, 2), and either unchanged or decreased rates of bone formation. Resistive exercise had been proposed as a countermeasure, and data from bed rest supported this concept (3). An interim resistive exercise device (iRED) was flown for early ISS crews. Unfortunately, the iRED provided no greater bone protection than on missions where only aerobic and muscular endurance exercises were available (4, 5). In 2008, the Advanced Resistive Exercise Device (ARED), a more robust device with much greater resistance capability, (6, 7) was launched to the ISS. Astronauts who had access to ARED, coupled with adequate energy intake and vitamin D status, returned from ISS missions with bone mineral densities virtually unchanged from preflight (7). Bone biochemical markers showed that while the resistive exercise and adequate energy consumption did not mitigate the increased bone resorption, bone formation was increased (7, 8). The typical drop in circulating parathyroid hormone did not occur in ARED crewmembers. In 2014, an updated look at the densitometry data was published. This study confirmed the initial findings with a much larger set of data. In 42 astronauts (33 male, 9 female), the bone mineral density response to flight was the same for men and women (9), and those with access to the ARED did not have the typical decrease in bone mineral density that was observed in early ISS crewmembers with access to the iRED (Figure 1) (7). Biochemical markers of bone formation and resorption responded similarly in men and women. These data are encouraging, and represent the first in-flight evidence in the history of human space flight that diet and exercise can maintain bone mineral density on long-duration missions. However, the maintenance of bone mineral density through bone remodeling, that is, increases in both resorption and formation, may yield a bone with strength characteristics different from those

  1. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available BACKGROUND: Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. MATERIALS AND METHODS: The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests. RESULTS: The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony

  2. High-dose therapy improved the bone remodelling compartment canopy and bone formation in multiple myeloma

    DEFF Research Database (Denmark)

    Hinge, Maja; Delaissé, Jean-Marie; Plesner, Torben;

    2015-01-01

    . Loss of this canopy has been associated with bone loss. This study addresses whether the bone remodelling in MM is improved by high-dose therapy. Bone marrow biopsies obtained from 20 MM patients, before and after first-line treatment with high-dose melphalan followed by autologous stem cell...... transplantation, and from 20 control patients with monoclonal gammopathy of undetermined significance were histomorphometrically investigated. This investigation confirmed that MM patients exhibited uncoupled bone formation to resorption and reduced canopy coverage. More importantly, this study revealed......Bone loss in multiple myeloma (MM) is caused by an uncoupling of bone formation to resorption trigged by malignant plasma cells. Increasing evidence indicates that the bone remodelling compartment (BRC) canopy, which normally covers the remodelling sites, is important for coupled bone remodelling...

  3. External resorption presenting as an intracoronal radiolucent lesion in a pre-eruptive tooth.

    LENUS (Irish Health Repository)

    McNamara, C M

    1997-09-01

    A large intracoronal radiolucent lesion in an unerupted permanent molar was found during the routine assessment of a young male Caucasian prior to orthodontic treatment. The tooth was extracted. Histological examination indicated the lesion was caused by external resorption. The defect extended widely into the enamel and dentine, and was repaired in part by bone. The pulp chamber was not involved. The aetiology of these lesions is often obscure but in this case it appeared to have originated in the floor of two developmental pits on the occlusal surface of the tooth.

  4. Negative effects of fertilization on plant nutrient resorption.

    Science.gov (United States)

    Yuan, Z Y; Chen, Han Y H

    2015-02-01

    Plants in infertile habitats are thought to have a high rate of nutrient resorption to enable them reuse nutrients more efficiently than those in fertile habitats. However, there is still much debate on how plant nutrient resorption responds to nutrient availability. Here we used a meta-analysis from a global data set of 9703 observations at 306 sites from 508 published articles to examine the effects of nitrogen (N) and phosphorus (P) fertilization on plant foliar N and P concentrations and resorption efficiency. We found that N fertilization enhanced N concentration in green leaves by 27% and P fertilization enhanced green-leaf P by 73% on average. The N and P concentrations in senesced leaves also increased with respective nutrient fertilization. Resorption efficiencies (percentage of nutrient recovered from senescing leaves) of both N and P declined in response to respective nutrient fertilization. Combined N and P fertilization also had negative effects on both N and P resorption efficiencies. Whether nutrient resorption efficiency differs among plant growth types and among ecosystems, however, remains uncertain due to the limited sample sizes when analyzed by plant growth types or ecosystem types. Our analysis indicates that fertilization decreases plant nutrient resorption and the view that nutrient resorption is a critical nutrient conservation strategy for plants in nutrient-poor environments cannot be abandoned. The response values to fertilization presented in our analysis can help improve biogeochemical models.

  5. Generalized cervical root resorption associated with periodontal disease

    NARCIS (Netherlands)

    Beertsen, W; Piscaer, M; Van Winkelhoff, AJ; Everts, P. A. M.

    2001-01-01

    Background and description of case: The etiology and pathogenesis of generalized cervical root resorptions is not well understood. In the present report, a case of severe cervical root resorption involving 24 anterior and posterior teeth is presented. The lesions developed within a period of 2 years

  6. Finite element analysis of bone loss around failing implants

    NARCIS (Netherlands)

    Wolff, J.; Narra, N.; Antalainen, A.K.; Valášek, J.; Kaiser, J.; Sandór, G.K.; Marcián, P.

    2014-01-01

    Dental implants induce diverse forces on their surrounding bone. However, when excessive unphysiological forces are applied, resorption of the neighbouring bone may occur. The aim of this study was to assess possible causes of bone loss around failing dental implants using finite element analysis. A

  7. Bone Remodelling Markers in Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Patrice Fardellone

    2014-01-01

    Full Text Available Bone loss in rheumatoid arthritis (RA patients results from chronic inflammation and can lead to osteoporosis and fractures. A few bone remodeling markers have been studied in RA witnessing bone formation (osteocalcin, serum aminoterminal propeptide of type I collagen (PINP, serum carboxyterminal propeptide of type I collagen (ICTP, bone alkaline phosphatase (BAP, osteocalcin (OC, and bone resorption: C-terminal telopeptide of type 1 collagen (I-CTX, N-terminal telopeptide of type 1 collagen (I-NTX, pyridinolines (DPD and PYD, and tartrate-resistant acid phosphatase (TRAP. Bone resorption can be seen either in periarticular bone (demineralization and erosion or in the total skeleton (osteoporosis. Whatever the location, bone resorption results from activation of osteoclasts when the ratio between osteoprotegerin and receptor activator of nuclear factor kappa-B ligand (OPG/RANKL is decreased under influence of various proinflammatory cytokines. Bone remodeling markers also allow physicians to evaluate the effect of drugs used in RA like biologic agents, which reduce inflammation and exert a protecting effect on bone. We will discuss in this review changes in bone markers remodeling in patients with RA treated with biologics.

  8. Management of internal resorption of central incisor using hybrid technique.

    Science.gov (United States)

    Gayathri, Prabakaran; Pandey, Ramesh Kumar; Jain, Eesha

    2014-01-28

    Internal inflammatory root resorption is characterised by progressive destruction of intraradicular dentin and dentinal tubules along the root canal wall. A number of theories have been proposed as a possible cause for internal resorption. It is usually asymptomatic and detected during routine radiographic investigations. Prompt diagnosis and early management of such defects is essential to maintain the integrity of the tooth. Non-surgical and surgical methods are the two main strategies involved in the management of internal resorption. The non-surgical method is usually preferred, but in cases of extensive resorption with external root perforation, surgical intervention has been advocated. The present case illustrates repair of perforating internal resorption by hybrid method, using mineral trioxide aggregate and gutta-percha, following surgical exposure. After a 10-month follow-up, no clinical and radiographic abnormalities were observed. Additionally, there was also marked reduction in periodontal pocket depth.

  9. Clinical Management of Two Root Resorption Cases in Endodontic Practice

    Directory of Open Access Journals (Sweden)

    Jozef Mincik

    2016-01-01

    Full Text Available Root resorption is a pathological process involving loss of hard dental tissues. It may occur as a consequence of dental trauma, orthodontic treatment, and bleaching, and occasionally it accompanies periodontal disease. Although the mechanism of resorption process is examined in detail, its etiology is not fully understood. Wide open apical foramen is more difficult to manage and the root canal may often overfill. In this report we present two cases of root resorption and describe means for its clinical management. We conclude that useful measure of a success or failure in managing root resorption is the persistence of the resorption process. It is a clear sign of an active ongoing inflammatory process and shows the clinical need for retreatment.

  10. Microstimulation at the bone-implant interface upregulates osteoclast activation pathways.

    Science.gov (United States)

    Stadelmann, Vincent A; Terrier, Alexandre; Pioletti, Dominique P

    2008-02-01

    Peri-implant bone resorption after total joint arthroplasty is a key parameter in aseptic loosening. Implant wear debris and biomechanical aspects have both been demonstrated to be part of the bone resorption process. However, neither of these two parameters has been clearly identified as the primary initiator of peri-implant bone resorption. For the biomechanical parameters, micromotions were measured at the bone-implant interface during normal gait cycles. The amplitude of the micromotions was shown to trigger differentiation of bone tissues. So far no data exists directly quantifying the effect of micromotion and compression on human bone. We hypothesize that micromotion and compression at the bone-implant interface may induce direct activation of bone resorption around the implant through osteoblasts-osteoclasts cell signaling in human bone. This hypothesis was tested with an ex vivo loading system developed to stimulate trabecular bone cores and mimic the micromotions arising at the bone-implant interface. Gene expression of RANKL, OPG, TGFB2, IFNG and CSF-1 was analyzed after no mechanical stimulation (control), exposure to compression or exposure to micromotions. We observed an 8-fold upregulation of RANKL after exposure to micromotions, and downregulation of OPG, IFNG and TGFB2. The RANKL:OPG ratio was upregulated 24-fold after micromotions. This suggests that the micromotions arising at the bone-implant interface during normal gait cycles induce a bone resorption response after only 1 h, which occurs before any wear debris particles enter the system.

  11. ['Door de beugel': resorption at dental elements].

    Science.gov (United States)

    Leunisse, M; Barendrecht, D S

    2015-09-01

    A twenty-year-old man was referred to an orthodontist for orthodontic re-treatment of dental element 32 by his dentist and a periodontist. At the buccal surface of the dental element a significant gingival resorption had occurred and the root of the element was located outside of the processus alveolaris buccally. This case will be presented at the thematic tour 'Door de beugel: team up' on 27 October 2015, which is organised by the Nederlandse Vereniging van Tandartsen (Dutch Dentists' Society) and will be held at 4 different locations in the Netherlands. Readers of the Nederlands Tijdschrift voor Tandheelkunde get an exclusive preview of the case. The treatment of choice will be published in the December 2015 issue.

  12. Quantification of Condylar Resorption in TMJ Osteoarthritis

    Science.gov (United States)

    Cevidanes, LHS; Hajati, A-K; Paniagua, B; Lim, PF; Walker, DG; Palconet, G; Nackley, AG; Styner, M; Ludlow, JB; Zhu, H; Phillips, C

    2010-01-01

    OBJECTIVE This study was performed to determine the condylar morphological variation of osteoarthritic (OA) and asymptomatic temporomandibular joints (TMJ) and to determine its correlation with pain intensity and duration. STUDY DESIGN Three dimensional surface models of mandibular condyles were constructed from Cone-Beam CT images of 29 female patients with TMJ OA (Research Diagnostic Criteria for Temporomandibular Disorders Group III) and 36 female asymptomatic subjects. Shape Correspondence was used to localize and quantify the condylar morphology. Statistical analysis was performed with MANCOVA analysis using Hotelling T2 metric based on covariance matrices, and Pearson correlation. RESULTS OA condylar morphology was statistically significantly different from the asymptomatic condyles (p<0.05). 3D morphological variation of the OA condyles was significantly correlated with pain intensity and duration. CONCLUSION 3D quantification of condylar morphology revealed profound differences between OA and asymptomatic condyles and the extent of the resorptive changes paralleled pain severity and duration. PMID:20382043

  13. 含高钙和维生素D的强化奶能有效提高健康的绝经后的中国女性体内的维生素D水平并减少骨吸收%High-calcium and vitamin D fortified milk is effective on improving vitamin D status and reducing bone resorption in Chinese healthy postmenopausal women

    Institute of Scientific and Technical Information of China (English)

    Marlena C Kruger; PengCheng Ha; Joanne M Todd; Barbara Kuhn-Sherlock; Linda M Schollum; Jiliang Ma; George Qin; Edith Lau

    2013-01-01

    目的 钙摄入水平低以及体内维生素D不足是导致亚洲女性罹患骨质疏松的危险因素.此项研究的目的 是评估高钙维生素D强化牛奶(HCM)对健康的中国绝经后妇女的体内维生素D状态和骨吸收标志物进行干预的影响.方法 本试验对象为55岁以上,绝经至少5年的女性.共有124名女性进行了总体健康状况和骨密度检查筛选.63名女性被随机分为对照组和试验组,试验组在12 w内每日饮用两次高钙/维生素D强化奶(含900 mg钙、96 mg镁、2.4 mg锌和6.4 μg维生素D).2组分别在试验开始、试验2 w、8 w和12 w时测量血矿物质、25(OH)维生素D3和Ⅰ型胶原C端肽(CTX)水平.结果 对照组女性平均年龄为63±4.6岁,高钙强化奶(HCM)组女性平均年龄为62±3.8岁.所测得的每日钙摄入量的基线值为HCM组260~482 mg,对照组为252~692 mg.12 w后HCM组的平均身体质量指数(BMI)显著降低(P<0.05).HCM组的血25(OH)维生素D3水平显著提高(33.13~39.49 nmol/L),而对照组则维持不变(29.27~28.21 nmol/L).HCM组的血CTX水平在0 w和2 w之间下降了25%,并保持不变直至第12w.从第2w开始HCM组和对照组相比血CTX水平就出现了显著差异(P<0.001).结论 通过饮用含高钙和维生素D的强化奶(HCM),在2至4w内能显著提高中国绝经妇女体内维生素D水平,并减少骨吸收破坏.如果长期持续地饮用含高钙和维生素D的强化奶(HCM),能减少骨吸收和骨量丢失的风险,从而减少患骨质疏松和由此引起骨折的风险.%Background Low calcium intake and insufficient vitamin D status are risk factors for osteoporosis amongst Asian women. The purpose of this study was to evaluate the effect of high-calcium and vitamin D fortified milk ( HCM ) intervention on vitamin D status and bone resorption markers in Chinese healthy postmenopausal women. Methods Women over 55 years old, and with at least a 5-year postmenopausal period were recruited. A total

  14. Patterns of distribution of phosphomono-esterases on surfaces of demineralized bone

    DEFF Research Database (Denmark)

    Kirkeby, S; Vilmann, H

    1979-01-01

    be an indication of differential processes of bone transformations in such a way that bone surfaces corresponding to areas of enzyme reactions are depository whereas bone surfaces corresponding to areas of lack of enzyme reaction are resorptive. New experimental designs are, however, necessary before...... to resorptive surfaces and weak reaction of cells adjacent to depository surfaces. When, however, Fast dark blue R was used all surface cells reacted markedly. This method also revealed certain cell types with nuclear reaction....

  15. Bone Remodeling Monitor

    Science.gov (United States)

    Foucar, Charlie; Goldberg, Leslie; Hon, Bodin; Moore, Shannon; Williams, Evan

    2009-01-01

    The impact of bone loss due to different mechanical loadings in microgravity is a major concern for astronauts upon reintroduction to gravitational forces in exploration missions to the Moon and Mars. it has been shown that astronauts not only lose bone at differing rates, with levels up to 2% per month, but each astronaut will respond to bone loss treatments differently. Pre- and post-flight imaging techniques and frozen urine samples for post-flight laboratory immunoassays To develop a novel, non-invasive, highly . sensitive, portable, intuitive, and low-powered device to measure bone resorption levels in 'real time' to provide rapid and Individualized feedback to maximize the efficacy of bone loss countermeasures 1. Collect urine specimen and analyze the level of bone resorption marker, DPD (deoxypridinoline) excreted. 2. Antibodies specific to DPD conjugated with nanoshells and mixed with specimen, the change in absorbance from agglutination is measured by an optical device. 3. The concentration of DPD is displayed and recorded on a PDA

  16. Remodelling of bone and bones. Effects of altered mechanical stress on anlages.

    Science.gov (United States)

    Storey, E; Feik, S A

    1982-04-01

    Tails from 4-day-old Sprague-Dawley rats were bent in situ or skinned bent tail segments were transplanted s.c. into 50 g hosts. Tissue changes were studied for up to 24 weeks by radiographic and histological techniques. The early changes in situ resulted largely from limited translation of bones within their encasing tissues with resorption on the leading (pressure) side inducing thinning, and on the trailing (tension) side thickening of bone. The changes in transplanted anlages occurred in 3 stages: initially, bending of the anlages, with tension between the stretched periosteum and the outer bone surface inducing formation, and compression of cartilage and bone on the inner aspect leading to resorption; then resumption of longitudinal growth and expansion of the bent loop leading to translation of bones within the encasing soft tissues with resorption and thinning of bone on the leading pressure side and formation, with thickening of the inner shaft, on the trailing tension side; and finally with cessation of growth and translation, a reversal to the previous phase. The results support the hypothesis that 2 processes are involved: first, internal stress, and second, translation of bones with, in all instances, pressure inducing resorption and tension inducing formation of bone.

  17. Effects of Resveratrol Supplementation on Bone Growth in Young Rats and Microarchitecture and Remodeling in Ageing Rats

    OpenAIRE

    Lee, Alice M. C.; Tetyana Shandala; Long Nguyen; Beverly S Muhlhausler; Ke-Ming Chen; Peter R Howe; Xian, Cory J.

    2014-01-01

    Osteoporosis is a highly prevalent skeletal disorder in the elderly that causes serious bone fractures. Peak bone mass achieved at adolescence has been shown to predict bone mass and osteoporosis related risk fracture later in life. Resveratrol, a natural polyphenol compound, may have the potential to promote bone formation and reduce bone resorption. However, it is unclear whether it can aid bone growth and bone mass accumulation during rapid growth and modulate bone metabolism during ageing...

  18. Androgen and bone mass in men

    Institute of Scientific and Technical Information of China (English)

    AnnieW.C.Kung

    2003-01-01

    Androgens have multiple actions on the skeleton throughout life. Androgens promote skeletal growth and accumulation of minerals during puberty and adolescence and stimulate osteoblast but suppress osteoclast function,activity and lifespan through complex mechanisms. Also androgens increase periosteal bone apposition, resulting in larger bone size and thicker cortical bone in men. There is convincing evidence to show that aromatization to estrogens was an important pathway for mediating the action of testosterone on bone physiology. Estrogen is probably the dominant sex steroid regulating bone resorption in men, but both testosterone and estrogen are important in maintaining bone formation. ( Asian J Androl 2003 Jun; 5: 148-154)

  19. Trafficking of Metastatic Breast Cancer Cells in Bone

    Science.gov (United States)

    2006-08-01

    visualized in the intact bone (i.e., the bone is not cut, but has been stripped of surrounding muscle ) 1 hour following intracardiac injection using...bone deposition and resorption could be altered as well by reducing osteoblast number or differentiation and/or activity (33). In vitro coculture of...Direct resorption of bone by human monocytes . Sci- ence1977;196:1109^11. 49.Hall CL,BaficoA,DaiJ,AaronsonSA,Keller ET.Pros- tate cancer cells promote

  20. An evaluation of root resorption after orthodontic treatment.

    Science.gov (United States)

    Thomas, E; Evans, W G; Becker, P

    2012-08-01

    Root resorption is commonly seen, albeit in varying degrees, in cases that have been treated orthodontically. In this retrospective study the objective was to compare the amount of root resorption observed after active orthodontic treatment had been completed with one of three different appliance systems, namely, Tip Edge, Modified Edgewise and Damon. The sample consisted of pre and post-treatment cephalograms of sixty eight orthodontic cases. Root resorption of the maxillary central incisor was assessed from pre- and post- treatment lateral ce phalograms using two methods. In the first, overall tooth length from the incisal edge to the apex was measured on both pre and post-treatment lateral cephalograms and root resorption was recorded as an actual millimetre loss of tooth length. There was a significant upward linear trend (p = 0.052) for root resorption from the Tip Edge Group to the Damon Group. In the second method root resorption was visually evaluated by using the five grade ordinal scale of Levander and Malmgren (1988). It was found that the majorty of cases in the sample came under Grade 1 and Grade 2 category of root resorption. Statistical evaluation tested the extent of agree ment in this study between visual measurements and actual measurements and demonstrated a significant association (p = 0.018) between the methods.

  1. Root resorption in relation to orthodontic tooth movement.

    Science.gov (United States)

    Ramanathan, Chaitra; Hofman, Zdenĕk

    2006-01-01

    Root resorption is an undesirable sequela of orthodontic tooth movement. The odontoclasts are responsible for root resorption and the process of hyalinization is known to preceed the orthodontic root resorption. It is found that there are several predisposing factors, therefore an evaluation of these factors should be done by careful examination of personal medical history, severity of malocclusion and dental treatment (if any due to previous history of trauma), anterior crossbite etc. The evaluation becomes an essential factor as it helps the orthodontists in detecting the occurance and severity of the root resorption and thereby plan out the treatment more effectively. Orthodontic tooth movements especially intrusion and other movements like tipping, torque are all known to influence the root resorption, therefore the detection using radiographs and repair of root resorption is of utmost significance as root resorption is a more serious problem from a medicolegal stand point of view. However some studies have shown that the repair process is known to occur after the cessation of orthodontic treatment by the deposition of cementum of cellular type. In the light of orthodontist's liability of what is basically an unpredictable phenomenon, it is necessary that the speciality define this uncertainity and protect its members against unnecessary and unjustified litigation.

  2. Dental root periapical resorption caused by orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Pinandi Sri Pudyani

    2006-03-01

    Full Text Available Dental root resorption especially in maxillary incisive region almost always happens simultaneously with orthodontic treatment, and it gained researchers attention, in particular after the use of periapical radiography. However, the fundamental etiology of dental root resorption is still dubious. Multifactoral causes are mentioned, among others are hormonal, nutritition, trauma, dental root form and dental root structure anomalies, genetic, while from treatment side are duration, types, strength scale and dental movement types. Based on these findings, orthodontic treatment was proven to cause dental root resorption in maxillary incisive teeth.

  3. Early and unusual incisor resorption due to impacted maxillary canines.

    Science.gov (United States)

    Otto, Ronald L

    2003-10-01

    A very early and severe case of maxillary incisor resorption caused by impacted canines is reported. An estimated 50,000 cases of ectopic eruption and impaction of maxillary canines occur each year in the United States. Although incisor resorption due to ectopically positioned permanent maxillary canines can be swift, silent, and devastating, an effective protocol has been developed for early detection and management of this condition. Palpation and, if indicated, radiographic evaluation are combined with primary canine removal in selected cases. These strategies--particularly when used early--can prevent the vast majority of palatally impacted maxillary canines and the potentially devastating resorption of adjacent incisors.

  4. Prevalence of dental resorptive lesions in Swedish cats.

    Science.gov (United States)

    Pettersson, A; Mannerfelt, T

    2003-09-01

    Ninety-six, randomly selected Swedish cats were evaluated for the presence of dental resorptive lesions. All cats were examined while receiving general anesthesia. Diagnosis was based on oral examination and full-mouth, intraoral dental radiographs. Information concerning age, sex, vaccination status, eating habits, food type, environment (indoor or outdoor housing), oral, discomfort, dental care, and medical treatment was recorded. Hematologic samples included analysis for FeLV, FIV, and calcivirus. Of the cats examined in this study, 32% had gross or radiographic signs of dental resorptive lesions. There was a positive relationship between the occurrence of dental resorptive lesions and increasing age.

  5. Bifunctional Bisphosphonates for Delivering Biomolecules to Bone

    Science.gov (United States)

    2012-01-13

    Osteoporosis primarily affects women after menopause (11). In general, menopause limits estrogen , which has an anti-resorptive characteristic, in the...several bone diseases. Since bisphosphonates (BPs) are known to have high affinity to bone mineral and are being widely used in treatment of osteoporosis ...diseases. Since bisphosphonates (BPs) are known to have high affinity to bone mineral and are being widely used in treatment of osteoporosis , they are well

  6. Androgens and bone.

    Science.gov (United States)

    Vanderschueren, Dirk; Vandenput, Liesbeth; Boonen, Steven; Lindberg, Marie K; Bouillon, Roger; Ohlsson, Claes

    2004-06-01

    Loss of estrogens or androgens increases the rate of bone remodeling by removing restraining effects on osteoblastogenesis and osteoclastogenesis, and also causes a focal imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, androgens, as well as estrogens, maintain cancellous bone mass and integrity, regardless of age or sex. Although androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs), can exert these effects, their relative contribution remains uncertain. Recent studies suggest that androgen action on cancellous bone depends on (local) aromatization of androgens into estrogens. However, at least in rodents, androgen action on cancellous bone can be directly mediated via AR activation, even in the absence of ERs. Androgens also increase cortical bone size via stimulation of both longitudinal and radial growth. First, androgens, like estrogens, have a biphasic effect on endochondral bone formation: at the start of puberty, sex steroids stimulate endochondral bone formation, whereas they induce epiphyseal closure at the end of puberty. Androgen action on the growth plate is, however, clearly mediated via aromatization in estrogens and interaction with ERalpha. Androgens increase radial growth, whereas estrogens decrease periosteal bone formation. This effect of androgens may be important because bone strength in males seems to be determined by relatively higher periosteal bone formation and, therefore, greater bone dimensions, relative to muscle mass at older age. Experiments in mice again suggest that both the AR and ERalpha pathways are involved in androgen action on radial bone growth. ERbeta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and

  7. 健康管理对老年人口腔微创种植体边缘骨稳定性的影响%Effects of health management of stomatology on the marginal bone resorption of minimally invasive implant in the elderly

    Institute of Scientific and Technical Information of China (English)

    栗洪师; 李冬霞; 冯岩; 臧晓霞

    2015-01-01

    Objective To evaluate the effects of health management of stomatology on the marginal bone resorption of minimally invasive implant in the elderly.Method Tottally 54 implants were placed in 37 elderly patients of missing teeth in maxillary molar areas and the patients were randomly divided into health management group and control group.Patients in the group of health management were guided to master the proper techniques of oral hygiene practices before and after the implantation and periodontal maintenance were carried out carefully until 1 year after loading of restoration.In the control group, oral hygiene was applied. X-ray and CBCT examinations were made and implant marginal alveolar bone loss (MBL) was measured 3, 6, 9, 12 months after loading with Planmeca PROMAX3D software. Besides, 3, 6, 9, 12 months after loading, improved plaque index (iPLI), modified bleeding index (mBI) and probing depth (PD) were also recorded. SPSS 15.0 was applied to analyze the data. Result Differences in diastolic and systolic blood pressure and changes in heart rate in patients during the intraoperative period were (8.86 ± 0.31) mmHg(1 mmHg=0.133 kPa), (19.18 ± 0.22) mmHg, (20.19 ± 1.84) times/min, which were significantly lower than those of the control group values [(16.55±1.08) mmHg, (28.31±2.30) mmHg, (20.19±1.84) times/min] (P<0.05 or 0.01);at 12 months after the load around the implant in oral health management group, the values of MBL and mSBI were 2.6 (2, 4), 2.1 (2, 4), which were significantly better than control group [4.3(3, 7), 4.3(3, 7)] (P<0.01);simultaneously, there was significant difference in the values of MBL and PD between experimental group (1.42 ± 0.03, 0.77 ± 0.24) and control group (1.59 ± 0.04, 0.54 ± 0.17) (P<0.01). Conclusion Well-performed health management of peri-implant could reduce the MBL and keep healthy soft tissue environment around implants.%目的:探讨口腔健康管理对于老年人围种植手术调节作用和种植修复

  8. What is the best balance of benefits and risks among anti-resorptive therapies for postmenopausal osteoporosis?

    Science.gov (United States)

    Miller, P D; Derman, R J

    2010-11-01

    Pharmacologic osteoporosis therapy, particularly anti-resorptives, is recommended in postmenopausal women with clinical risk factors for fracture. Treatment decisions should be made based on the relative benefit-risk profile in different patient populations. Emerging options [e.g., selective estrogen receptor modulators (SERMs) and denosumab] may hold promise for providing protection from bone loss and for fracture risk reduction.Osteoporosis, the most common clinical disorder of bone metabolism, is characterized by low bone mineral density, deterioration of microarchitecture, and a consequent increase in bone fragility and risk of fracture. Pharmacologic therapy is recommended in postmenopausal women with clinical risk factors for fracture and includes anti-resorptive agents such as bisphosphonates, hormone therapy, SERMs, and calcitonin. The anabolic agent teriparatide (parathyroid hormone) is usually reserved for high-risk patients or those with glucocorticoid-induced osteoporosis. Strontium ranelate, available outside the USA, has both anti-resorptive and anabolic properties. Supplementation with calcium and vitamin D is recommended for all women aged 50 years and older. Bisphosphonates are often considered first-line therapy for osteoporosis and have the largest base of clinical trial data showing efficacy for global fracture risk reduction. Low-dose hormone therapy is appropriate for younger women who are experiencing other menopausal symptoms. In women for whom bisphosphonates are not appropriate or not tolerated or in younger postmenopausal women who have a low risk for hip fracture, SERMs are a suitable treatment option. Calcitonin is designated for patients who are unable or unwilling to tolerate other osteoporosis agents. Emerging options, including newer SERMs (e.g., bazedoxifene and lasofoxifene) and the monoclonal antibody denosumab, may hold promise for providing protection from bone loss and for fracture risk reduction. Because no single agent is

  9. The significance of a differential distribution of phosphomonoesterases on bone surfaces after prolonged demineralization

    DEFF Research Database (Denmark)

    Vilmann, H; Kirkeby, S

    1979-01-01

    with the patterns of apposition and resorption on the periosteal surfaces of this bone, revealed by in vivo staining with alizarin red S. Presence of reaction to acid phosphatase is, as shown before, an indication of resorptive surfaces, while the presence of reaction to alkaline phosphatase is an indication...

  10. In vivo monitoring of bone architecture and remodeling after implant insertion: The different responses of cortical and trabecular bone.

    Science.gov (United States)

    Li, Zihui; Kuhn, Gisela; von Salis-Soglio, Marcella; Cooke, Stephen J; Schirmer, Michael; Müller, Ralph; Ruffoni, Davide

    2015-12-01

    The mechanical integrity of the bone-implant system is maintained by the process of bone remodeling. Specifically, the interplay between bone resorption and bone formation is of paramount importance to fully understand the net changes in bone structure occurring in the peri-implant bone, which are eventually responsible for the mechanical stability of the bone-implant system. Using time-lapsed in vivo micro-computed tomography combined with new composite material implants, we were able to characterize the spatio-temporal changes of bone architecture and bone remodeling following implantation in living mice. After insertion, implant stability was attained by a quick and substantial thickening of the cortical shell which counteracted the observed loss of trabecular bone, probably due to the disruption of the trabecular network. Within the trabecular compartment, the rate of bone formation close to the implant was transiently higher than far from the implant mainly due to an increased mineral apposition rate which indicated a higher osteoblastic activity. Conversely, in cortical bone, the higher rate of bone formation close to the implant compared to far away was mostly related to the recruitment of new osteoblasts as indicated by a prevailing mineralizing surface. The behavior of bone resorption also showed dissimilarities between trabecular and cortical bone. In the former, the rate of bone resorption was higher in the peri-implant region and remained elevated during the entire monitoring period. In the latter, bone resorption rate had a bigger value away from the implant and decreased with time. Our approach may help to tune the development of smart implants that can attain a better long-term stability by a local and targeted manipulation of the remodeling process within the cortical and the trabecular compartments and, particularly, in bone of poor health.

  11. Acidosis, hypoxia and bone.

    Science.gov (United States)

    Arnett, Timothy R

    2010-11-01

    Bone homeostasis is profoundly affected by local pH and oxygen tension. It has long been recognised that the skeleton contains a large reserve of alkaline mineral (hydroxyapatite), which is ultimately available to neutralise metabolic H(+) if acid-base balance is not maintained within narrow limits. Bone cells are extremely sensitive to the direct effects of pH: acidosis inhibits mineral deposition by osteoblasts but it activates osteoclasts to resorb bone and other mineralised tissues. These reciprocal responses act to maximise the availability of OH(-) ions from hydroxyapatite in solution, where they can buffer excess H(+). The mechanisms by which bone cells sense small pH changes are likely to be complex, involving ion channels and receptors in the cell membrane, as well as direct intracellular effects. The importance of oxygen tension in the skeleton has also long been known. Recent work shows that hypoxia blocks the growth and differentiation of osteoblasts (and thus bone formation), whilst strongly stimulating osteoclast formation (and thus bone resorption). Surprisingly, the resorptive function of osteoclasts is unimpaired in hypoxia. In vivo, tissue hypoxia is usually accompanied by acidosis due to reduced vascular perfusion and increased glycolytic metabolism. Thus, disruption of the blood supply can engender a multiple negative impact on bone via the direct actions of reduced pO(2) and pH on bone cells. These observations may contribute to our understanding of the bone disturbances that occur in numerous settings, including ageing, inflammation, fractures, tumours, anaemias, kidney disease, diabetes, respiratory disease and smoking.

  12. Apical root resorption in patients wearing orthodontic appliances.

    Science.gov (United States)

    Ousehal, L; Lazrak, L; Essmaali, F E; Ngom, P I

    2012-09-01

    The aim of our study was to evaluate the incidence of orthodontically induced root resorption during the tooth alignment and leveling phase, and to assess the impact of the variables age, sex and degree and direction of incisor displacement. We studied a consulting population at the dentofacial orthopaedics unit of the Dental Consultation and Treatment Centre (DCTC), Casablanca. Our sample was composed of 30 exposed cases and 30 non-exposed cases, followed up for a period of 8 months. A survey document was drawn up for data collection, and retro-alveolar radiographic imaging was used to evaluate resorption. Our results showed that the patients receiving orthodontic treatment all developed minor root resorptions during the alignment and levelling phase in the incisor group. We found that the central incisors underwent greater resorption than the lateral incisors.

  13. Condylar resorption in orthognathic surgery. The role of intermaxillary fixation.

    Science.gov (United States)

    Bouwman, J P; Kerstens, H C; Tuinzing, D B

    1994-08-01

    Condylar resorption that occurs after orthognathic surgery was investigated in a large sample of patients treated in the Department of Oral and Maxillofacial Surgery of the Free University in Amsterdam, the Netherlands. The findings correspond with previous publications on this subject. In a 1-year follow-up study the role of intermaxillary fixation was investigated radiologically. In a group of 158 patients prone to show occurrence of condylar resorption, 24 (26.4%) of the 91 patients treated with intermaxillary fixation showed signs of condylar resorption. In the group of 67 patients treated without intermaxillary fixation only eight (11.9%) of the patients showed signs of reduced volume of the condyle. Avoidance of intermaxillary fixation seems to reduce the incidence of condylar resorption after orthognathic surgery in patients with a mandibular deficiency with high mandibular plane angle.

  14. Nutrient resorption is associated with leaf vein density and growth performance of dipterocarp tree species

    NARCIS (Netherlands)

    Zhang, J.L.; Zhang, S.B.; Chen, Y.J.; Zhang, Y.P.; Poorter, L.

    2015-01-01

    1.Nutrient resorption is important for the nutrient budget of plants, but little is known about which plant traits mediate nutrient resorption, how resorption efficiency is associated with other leaf traits and whether nutrient resorption has an impact on plant growth. 2.In this study, 17 dipterocar

  15. Glucocorticoids maintain human osteoclasts in the active mode of their resorption cycle

    DEFF Research Database (Denmark)

    Søe, Kent; Delaissé, Jean-Marie

    2010-01-01

    as a negative-feedback loop, switching resorptive activity off and promoting migration to a new resorption site, thereby generating an additional resorption pit. We conclude that glucocorticoids change the osteoclastic resorption mode from intermittent to continuous and speculate that this change may contribute...

  16. Treatment with eldecalcitol positively affects mineralization, microdamage, and collagen crosslinks in primate bone.

    Science.gov (United States)

    Saito, Mitsuru; Grynpas, Marc D; Burr, David B; Allen, Matthew R; Smith, Susan Y; Doyle, Nancy; Amizuka, Norio; Hasegawa, Tomoka; Kida, Yoshikuni; Marumo, Keishi; Saito, Hitoshi

    2015-04-01

    Eldecalcitol (ELD), an active form of vitamin D analog approved for the treatment of osteoporosis in Japan, increases lumbar spine bone mineral density (BMD), suppresses bone turnover markers, and reduces fracture risk in patients with osteoporosis. We have previously reported that treatment with ELD for 6 months improved the mechanical properties of the lumbar spine in ovariectomized (OVX) cynomolgus monkeys. ELD treatment increased lumbar BMD, suppressed bone turnover markers, and reduced histomorphometric parameters of both bone formation and resorption in vertebral trabecular bone. In this study, we elucidated the effects of ELD on bone quality (namely, mineralization, microarchitecture, microdamage, and bone collagen crosslinks) in OVX cynomolgus monkeys in comparison with OVX-vehicle control monkeys. Density fractionation of bone powder prepared from lumbar vertebrae revealed that ELD treatment shifted the distribution profile of bone mineralization to a higher density, and backscattered electron microscopic imaging showed improved trabecular bone connectivity in the ELD-treated groups. Higher doses of ELD more significantly reduced the amount of microdamage compared to OVX-vehicle controls. The fractionated bone powder samples were divided according to their density, and analyzed for collagen crosslinks. Enzymatic crosslinks were higher in both the high-density (≥2.0 mg/mL) and low-density (mineralization, but prevented non-enzymatic reaction of collagen crosslinks and accumulation of bone microdamage. Bone anti-resorptive agents such as bisphosphonates slow down bone remodeling so that bone mineralization, bone microdamage, and non-enzymatic collagen crosslinks all increase. Bone anabolic agents such as parathyroid hormone decrease bone mineralization and bone microdamage by stimulating bone remodeling. ELD did not fit into either category. Histological analysis indicated that the ELD treatment strongly suppressed bone resorption by reducing the number of

  17. Inducible models of bone loss.

    Science.gov (United States)

    Doucette, Casey R; Rosen, Clifford J

    2014-12-11

    Bone is an essential organ that not only confers structural stability to the organism, but also serves as a reservoir for hematopoietic elements and is thought to affect systemic homeostasis through the release of endocrine factors as well as calcium. The loss of bone mass due to an uncoupling of bone formation and bone resorption leads to increased fragility that can result in devastating fractures. Further understanding of the effects of environmental stimuli on the development of bone disease in humans is needed, and they can be studied using animal models. Here, we present established and novel methods for the induction of bone loss in mice, including manipulation of diet and environment, administration of drugs, irradiation, and surgically induced hormone deficiency. All of these models are directly related to human cases, and thus, can be used to investigate the causes of bone loss resulting from these interventions.

  18. Resorption Rate Tunable Bioceramic: Si, Zn-Modified Tricalcium Phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Xiang [Iowa State Univ., Ames, IA (United States)

    2006-01-01

    This dissertation is organized in an alternate format. Several manuscripts which have already been published or are to be submitted for publication have been included as separate chapters. Chapter 1 is a general introduction which describes the dissertation organization and introduces the human bone and ceramic materials as bone substitute. Chapter 2 is the background and literature review on dissolution behavior of calcium phosphate, and discussion of motivation for this research. Chapter 3 is a manuscript entitled ''Si,Zn-modified tricalcium phosphate: a phase composition and crystal structure study'', which was published in ''Key Engineering Materials'' [1]. Chapter 4 gives more crystal structure details by neutron powder diffraction, which identifies the position for Si and Zn substitution and explains the stabilization mechanism of the structure. A manuscript entitled ''Crystal structure analysis of Si, Zn-modified Tricalcium phosphate by Neutron Powder Diffraction'' will be submitted to Biomaterials [2]. Chapter 5 is a manuscript, entitled ''Dissolution behavior and cytotoxicity test of Si, Zn-modified tricalcium phosphate'', which is to be submitted to Biomaterials [3]. This paper discusses the additives effect on the dissolution behavior of TCP, and cytotoxicity test result is also included. Chapter 6 is the study of hydrolysis process of {alpha}-tricalcium phosphate in the simulated body fluid, and the phase development during drying process is discussed. A manuscript entitled ''Hydrolysis of {alpha}-tricalcium phosphate in simulated body fluid and phase transformation during drying process'' is to be submitted to Biomaterials [4]. Ozan Ugurlu is included as co-authors in these two papers due to his TEM contributions. Appendix A is the general introduction of the materials synthesis, crystal structure and preliminary dissolution result. A manuscript entitled

  19. Inflammatory root resorption in primary molars: prevalence and associated factors

    Directory of Open Access Journals (Sweden)

    Raquel Gonçalves Vieira-Andrade

    2012-08-01

    Full Text Available This study aimed at determining the prevalence of inflammatory root resorption and associated factors in 1068 primary mandibular molars in 453 children 3 to 12 years of age. Age, dental history and medical history were recorded using a questionnaire administered to the children's parents/caregivers. Previously trained and calibrated examiners assessed radiographic images of the primary molars by direct observation, with the aid of a viewing box. Root resorption (physiological or inflammatory, dental crown status (healthy, carious with no pulp involvement, carious with pulp involvement and evidence of restoration, and pulpotomy or pulpectomy were determined. Data analysis involved descriptive statistics, the chi-square test and a multiple logistic regression (p < 0.05. The prevalence of inflammatory root resorption was 16.2% (n = 173. The male gender (OR: 1.4; 95% CI, the 3-to-7-years age bracket (OR: 1.5; 95% CI, an unhealthy dental crown (OR: 8.7; 95% CI, caries with pulp involvement (OR: 7.4; 95% CI, pulpotomy (OR: 3.1; 95% CI, and pulpectomy (OR: 5.4; 95% CI were risk factors for the occurrence of inflammatory root resorption in primary molars. In conclusion, the prevalence of inflammatory root resorption in the present sample was 16.2%. Gender, age, an unhealthy tooth, caries with pulp involvement, pulpotomy, pulpectomy, and the absence of a restoration were associated with a higher occurrence of inflammatory root resorption in primary molars.

  20. Serum markers of bone metabolism show bone loss in hibernating bears

    Science.gov (United States)

    Donahue, S.W.; Vaughan, M.R.; Demers, L.M.; Donahue, H.J.

    2003-01-01

    Disuse osteopenia was studied in hibernating black bears (Ursus americanus) using serum markers of bone metabolism. Blood samples were collected from male and female, wild black bears during winter denning and active summer periods. Radioimmunoassays were done to determine serum concentrations of cortisol, the carboxy-terminal cross-linked telopeptide, and the carboxy-terminal propeptide of Type I procollagen, which are markers of hone resorption and formation, respectively. The bone resorption marker was significantly higher during winter hibernation than it was in the active summer months, but the bone formation marker was unchanged, suggesting an imbalance in bone remodeling and a net bone loss during disuse. Serum cortisol was significantly correlated with the bone resorption marker, but not with the bone formation marker. The bone formation marker was four- to fivefold higher in an adolescent and a 17-year-old bear early in the remobilization period compared with the later summer months. These findings raise the possibility that hibernating black bears may minimize bone loss during disuse by maintaining osteoblastic function and have a more efficient compensatory mechanism for recovering immobilization-induced bone loss than that of humans or other animals.

  1. Bone formation is not impaired by hibernation (disuse) in black bears Ursus americanus

    Science.gov (United States)

    Donahue, S.W.; Vaughan, M.R.; Demers, L.M.; Donahue, H.J.

    2003-01-01

    Disuse by bed rest, limb immobilization or space flight causes rapid bone loss by arresting bone formation and accelerating bone resorption. This net bone loss increases the risk of fracture upon remobilization. Bone loss also occurs in hibernating ground squirrels, golden hamsters, and little brown bats by arresting bone formation and accelerating bone resorption. There is some histological evidence to suggest that black bears Ursus americanus do not lose bone mass during hibernation (i.e. disuse). There is also evidence suggesting that muscle mass and strength are preserved in black bears during hibernation. The question of whether bears can prevent bone loss during hibernation has not been conclusively answered. The goal of the current study was to further assess bone metabolism in hibernating black bears. Using the same serum markers of bone remodeling used to evaluate human patients with osteoporosis, we assayed serum from five black bears, collected every 10 days over a 196-day period, for bone resorption and formation markers. Here we show that bone resorption remains elevated over the entire hibernation period compared to the pre-hibernation period, but osteoblastic bone formation is not impaired by hibernation and is rapidly accelerated during remobilization following hibernation.

  2. The Rho-GEF Kalirin regulates bone mass and the function of osteoblasts and osteoclasts

    OpenAIRE

    2013-01-01

    Bone homeostasis is maintained by the balance between bone resorption by osteoclasts and bone formation by osteoblasts. Dysregulation in the activity of the bone cells can lead to osteoporosis, a disease characterized by low bone mass and an increase in bone fragility and risk of fracture. Kalirin is a novel GTP-exchange factor protein that has been shown to play a role in cytoskeletal remodeling and dendritic spine formation in neurons. We examined Kalirin expression in skeletal tissue and f...

  3. Calcium enriched mixture cement for primary molars exhibiting root perforations and extensive root resorption: report of three cases.

    Science.gov (United States)

    Tavassoli-Hojjati, Sara; Kameli, Somayeh; Rahimian-Emam, Sara; Ahmadyar, Maryam; Asgary, Saeed

    2014-01-01

    In primary molars with root perforations of endodontic origin, tooth extraction and space maintainer are recommended. Calcium-enriched mixture (CEM) cement is a new biomaterial demonstrating favorable sealability/biocompatibility. This report presents a novel treatment modality for cases of primary molar teeth with root perforations associated with a periodontal lesion due to extensive inflammatory root resorption, whereby CEM was used as a perforation repair/pulpotomy biomaterial. Three cases of primary molar root perforations due to inflammatory resorption were selected; all cases were associated with furcal lesions of endodontic origin. Pulp chambers were accessed/irrigated with NaOCl; the root canal orifices were filled with CEM and restored with stainless steel crowns. Clinical/radiographic examinations up to 17 months revealed that all teeth were functional and free of signs/symptoms of infection and all had complete bone healing. Further trials are suggested to confirm CEM use for management of root perforations in primary molars exhibiting root perforation.

  4. Three-Dimensional Quantification of Calcium Salt-Composite Resorption (CSC) In Vitro by Micro-computed Tomography (Micro-CT)

    Science.gov (United States)

    Winkler, T.; Dai, X. Y.; Mielke, G.; Vogt, S.; Buechner, H.; Schantz, J. T.; Harder, Y.; Machens, H. G.; Morlock, M. M.; Schilling, A. F.

    2014-04-01

    The commonly applied cell-based, two-dimensional (2D) in vitro resorption assays for biomaterials are limited in a variety of cases, including high initial roughness of material surface, uncontrollable solubilization (or resorption) of the entire material surface, or complex three-dimensional (3D) structure of the bioactive material itself. All these make the accurate assessment and successful selection of the optimal bone substitute material difficult. In vivo, micro-computed tomography (micro-CT) has been widely applied for the analysis of bone physiology and pathology, as well as for the 3D analysis of scaffolds for bone tissue engineering. In this study, we show that micro-CT can also be applied for the in vitro analysis of osteoclast-mediated resorption of biomaterials. For our experiments, we chose a calcium salt-composite (composite of calcium sulphate (CSC), calcium carbonate, glycerin-1,2,3-tripalmiate), which evades common 2D in vitro resorption analysis as a result of its high surface roughness and material composition. Human osteoclasts were differentiated from precursor cells on the surface of the material for 28 days. Cells were analyzed for expression of tartrate-resistant acid phosphatase 5b (TRAP5b), multinuclearity, and size. Volumetric analysis of resorption was performed by micro-CT. Multinucleated osteoclasts developed on the surface of the material. TRAP5b expression of the cells on CSC was comparable with TRAP5b expression of cells cultivated on dentin for the first 3 weeks of culture. At day 28, TRAP5b expression, cell number, and size of the TRAP+ cells were reduced on the CSC when compared with cells on dentin. Volumetric anaylsis by micro-CT showed a strong cellular effect on resorption of CSC. We consider micro-CT to be a promising technique for 3D quantification of cell-based resorption that will allow the study of cellular resorption of materials in vitro, which were up to now confined to animal experimental analysis.

  5. Low bone turnover phenotype in Rett syndrome

    DEFF Research Database (Denmark)

    Roende, Gitte; Petersen, Janne; Ravn, Kirstine;

    2014-01-01

    Background:Patients with Rett syndrome (RTT) are at risk of having low bone mass and low-energy fractures.Methods:We characterised bone metabolism by both bone formation and resorption markers in blood in a RTT population of 61 girls and women and 122 well-matched healthy controls. Levels of N...... of the lumbar spine (vBMADspine) and femoral neck (vBMADneck). We examined biochemical bone marker levels overall, and stratified to persons younger than age 25 years or equal to or older than age 25 years.Results:The RTT patients had reduced levels of all biochemical bone markers (p...

  6. Hypercalciuric Bone Disease

    Science.gov (United States)

    Favus, Murray J.

    2008-09-01

    Hypercalciuria plays an important causal role in many patients with calcium oxalate (CaOx) stones. The source of the hypercalciuria includes increased intestinal Ca absorption and decreased renal tubule Ca reabsorption. In CaOx stone formers with idiopathic hypercalciuria (IH), Ca metabolic balance studies have revealed negative Ca balance and persistent hypercalciuria in the fasting state and during low dietary Ca intake. Bone resorption may also contribute to the high urine Ca excretion and increase the risk of bone loss. Indeed, low bone mass by DEXA scanning has been discovered in many IH patients. Thiazide diuretic agents reduce urine Ca excretion and may increase bone mineral density (BMD), thereby reducing fracture risk. Dietary Ca restriction that has been used unsuccessfully in the treatment of CaOx nephrolithiasis in the past may enhance negative Ca balance and accelerate bone loss. DEXA scans may demonstrate low BMD at the spine, hip, or forearm, with no predictable pattern. The unique pattern of bone histologic changes in IH differs from other causes of low DEXA bone density including postmenopausal osteoporosis, male hypogonadal osteoporosis, and glucocorticoid-induced osteoporosis. Hypercalciuria appears to play an important pathologic role in the development of low bone mass, and therefore correction of urine Ca losses should be a primary target for treatment of the bone disease accompanying IH.

  7. [Cytokines in bone diseases. Cytokine and postmenopausal osteoporosis].

    Science.gov (United States)

    Inada, Masaki; Miyaura, Chisato

    2010-10-01

    Bone resorption is regulated by various cytokines. In postmenopausal osteoporosis, bone loss due to estrogen deficiency is closely related to the production of bone-resorbing cytokine. Especially, the increased production of IL-1, IL-6 and TNF-α could induce the expression of RANKL in bone tissues to enhance osteoclastogenesis. Relationship between estrogen deficiency and various cytokines is important to clarify the pathogenesis of postmenopausal osteoporosis.

  8. Tissue reaction and material biodegradation of a calcium sulfate/apatite biphasic bone substitute in rat muscle

    Directory of Open Access Journals (Sweden)

    Jian-Sheng Wang

    2016-07-01

    Conclusion: Calcium sulfate hydroxyapatite bone substitute can be used as a carrier for antibiotics or other drugs, without adverse reaction due to the fast resorption of the calcium sulfate. No bone formation was seen despite treating the bone substitute with autologous bone marrow.

  9. In vitro osteoclast formation and resorption of silicon-substituted hydroxyapatite ceramics.

    Science.gov (United States)

    Friederichs, Robert J; Brooks, Roger A; Ueda, Masato; Best, Serena M

    2015-10-01

    Materials that participate in bone remodeling at the implant/tissue interface represent a modern tissue engineering approach with the aim of balancing implant resorption and nascent tissue formation. Silicon-substituted hydroxyapatite (SiHA) ceramics are capable of stimulating new bone formation, but little is known about their interaction with osteoclasts (OC). The effects of soluble silicate and SiHA on OCs were investigated in this study. Soluble silicate below 500 μM did not stimulate cell metabolism at 4 days or alter resorption area at 7 days on calcium phosphate discs. On sintered ceramics, OC numbers were similar on HA, Si0.3 HA (0.5 wt % Si) and Si0.5 HA (1.2 wt % Si) after 21 days in vitro, but actin ring sealing zone morphology on SiHA resembled that commonly found on bone or on carbonate-substituted hydroxyapatite (CHA). Smaller and thicker actin rings on SiHA as compared to HA were probably the result of altered surface chemistry and solubility differences. The more stable sealing zones and increased lattice solubility likely contributed to increased individual pit volumes observed on Si0.5 HA. The delayed formation of OCs on Si0.5 HA (lower numbers at day 14) excludes earlier differentiation as a possible mechanism of increased individual OC pit volumes at later times (day 21). Materials characterization of Si containing biomaterials remains paramount as the Si type and amounts can subsequently impact downstream OC behaviour in a complex manner.

  10. USE OF PANORAMIC RADIOGRAPHS FOR EVALUATION OF MAXILLARY AND MANDIBULAR RESIDUAL RIDGE RESORPTION: IN VITRO STUDY

    Directory of Open Access Journals (Sweden)

    Priyanka

    2014-11-01

    Full Text Available : INTRODUCTION: Progressive ridge resorption is one of the main causes of loss of stability and retention of mandibular complete dentures. The location of the mental foramen can be identified easily on panoramic radiographs, and radiographic examinations are considered an important component of Prosthodontics diagnostic and treatment planning. Also the location of maxillary landmark is important to known how much resorption is there. Aim: To determine the average ratio of bone height with nearest constant anatomical landmarks in maxilla and in mandible. OBJECTIVE: To find out the association between radiographic findings & prosthodontics, such as measurements of the amount of resorption and the variation in the treatment planning of edentulous patients. METHODS: The subjects OPG was taken using standard radiographic procedural parameters. The measurement was done for distance ‘c’, ‘a’, ‘x’, ‘y’, ‘z’. Then the calculations from measurements were done to calculate the ratio of c/a, to calculate the ratio of x/y, to calculate the ratio of x/z. RESULT: The descriptive statistics was done. The C/a ratio mean is 2.71 ± 0.31. The X/Y ratio mean is 1.49 ± 0.34 and the X/Z ratio mean is 1.51 ± 0.24. CONCLUSION: This ratio can be assessed in edentulous patients and then there further treatment plan can be decided according to the ratio. The implant placement can be assessed by using the measurements in this study.

  11. Diabetes mellitus related bone metabolism and periodontal disease

    Institute of Scientific and Technical Information of China (English)

    Ying-Ying Wu; E Xiao; Dana T Graves

    2015-01-01

    Diabetes mellitus and periodontal disease are chronic diseases affecting a large number of populations worldwide. Changed bone metabolism is one of the important long-term complications associated with diabetes mellitus. Alveolar bone loss is one of the main outcomes of periodontitis, and diabetes is among the primary risk factors for periodontal disease. In this review, we summarise the adverse effects of diabetes on the periodontium in periodontitis subjects, focusing on alveolar bone loss. Bone remodelling begins with osteoclasts resorbing bone, followed by new bone formation by osteoblasts in the resorption lacunae. Therefore, we discuss the potential mechanism of diabetes-enhanced bone loss in relation to osteoblasts and osteoclasts.

  12. Bone histomorphometry in children with newly diagnosed acute lymphoblastic leukemia

    NARCIS (Netherlands)

    Leeuw, JA; Koudstaal, J; Wiersema-Buist, J; Kamps, WA; Timens, W

    2003-01-01

    The objective of this study was to obtain insight into bone formation and resorption in children with newly diagnosed untreated acute lymphoblastic leukemia (ALL). In 23 consecutive children with ALL, a bone biopsy was taken from the crista iliaca posterior under ketamine anesthesia, together with t

  13. The effect of photobiomodulation on root resorption during orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Nimeri G

    2014-01-01

    Full Text Available Ghada Nimeri, Chung H Kau, Rachel Corona, Jeffery Shelly Department of Orthodontics, University of Alabama, Birmingham, AL, USA Abstract: Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm2 continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little's Irregularity Index (>2 mm in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little's Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little's Irregularity Index and root resorption was detected. Keywords: photobiomodulation, root resorption, accelerate tooth movement, orthodontics, cone beam computed tomography

  14. Spontaneous resorption of a large cervical herniated nucleus pulposus.

    Science.gov (United States)

    Cvetanovich, Gregory L; Hsu, Andrew R; Frank, Rachel M; An, Howard S; Andersson, Gunnar B

    2014-07-01

    The majority of patients with symptomatic herniated discs can be successfully and conservatively managed and can achieve clinical improvement without surgical intervention. Resorption of the herniated nucleus pulposus (HNP) is 1 conservative mechanism for clinical improvement. We present the case of a 76-year-old healthy man with acute cervical radicular right arm pain and positive Spurling test. Magnetic resonance imaging (MRI) showed a large disc extrusion behind the C6 vertebral body, causing severe central canal stenosis and right-greater-than-left foraminal stenosis. The patient did not want surgical intervention, and his symptoms resolved with conservative treatment. A follow-up MRI 7 months after his initial presentation showed almost complete resorption of the herniated disc. The patient returned to his normal activities and has not had recurrence of symptoms for 2 years. This report provides an interesting example of complete resorption of a large, extruded cervical herniated disc in a symptomatic patient and a review of the literature on resorption of herniated discs. The review suggests that larger herniations with an epidural location (penetration of the posterior longitudinal ligament) have a greater chance of resorption.

  15. Deciduous canine and permanent lateral incisor differential root resorption.

    Science.gov (United States)

    Davies, K R; Schneider, G B; Southard, T E; Hillis, S L; Wertz, P W; Finkelstein, M; Hogan, M M

    2001-10-01

    When a permanent maxillary canine erupts apical to the permanent lateral incisor and the deciduous canine, resorption typically takes place only on the deciduous canine root. An understanding of this differential resorption could provide insight into the reasons for excessive iatrogenic root resorption during orthodontic tooth movement. The purpose of the present study was to examine the response of roots of permanent lateral incisors and deciduous canines to simulated resorption, and to acid and enzyme attack, reflecting the physiologic environment of an erupting permanent canine. Groups of maxillary permanent lateral incisor and deciduous canine roots were exposed to 5 combinations of Ten Cate demineralizing solution, Ten Cate demineralizing solution with EDTA, and a Type I collagenase solution. Sections of the roots were examined under a polarized light microscope. Analysis of variation of the resulting root lesions demonstrated that the lesion depths for deciduous canines were greater than those for permanent lateral incisors when averaged across 4 of the conditions (F(1,24) = 7.49, P =.0115). On average, deciduous canine roots demonstrated lesions 10% deeper than did permanent lateral incisor roots. We concluded that when deciduous canine and permanent lateral incisor roots are subjected to acid and enzyme attack, reflecting the physiologic environment of an erupting permanent canine, significantly deeper demineralized lesions are seen in the deciduous roots compared with the permanent roots. This finding may partially explain the differential root resorption during permanent tooth eruption.

  16. Bone phenotypes of P2 receptor knockout mice

    DEFF Research Database (Denmark)

    Orriss, Isabel; Syberg, Susanne; Wang, Ning;

    2011-01-01

    The action of extracellular nucleotides is mediated by ionotropic P2X receptors and G-protein coupled P2Y receptors. The human genome contains 7 P2X and 8 P2Y receptor genes. Knockout mice strains are available for most of them. As their phenotypic analysis is progressing, bone abnormalities have...... been observed in an impressive number of these mice: distinct abnormalities in P2X7-/- mice, depending on the gene targeting construct and the genetic background, decreased bone mass in P2Y1-/- mice, increased bone mass in P2Y2-/- mice, decreased bone resorption in P2Y6-/- mice, decreased bone...... formation and bone resorption in P2Y13-/- mice. These findings demonstrate the unexpected importance of extracellular nucleotide signalling in the regulation of bone metabolism via multiple P2 receptors and distinct mechanisms involving both osteoblasts and osteoclasts....

  17. Effect of prostaglandins E1, E2, and F2 alpha on osteoclast formation in mouse bone marrow cultures

    Energy Technology Data Exchange (ETDEWEB)

    Collins, D.A.; Chambers, T.J. (St. George' s Hospital Medical School, London (United Kingdom))

    1991-02-01

    Prostaglandins (PG) act as direct inhibitors of mature osteoclasts, but although resorption-inhibition is also observed initially PG increase bone resorption in organ culture. This suggests that PG influence bone resorption in organ culture through actions on cell types other than mature osteoclasts. We have therefore tested the effects of PG E1, E2, and F2 alpha on the differentiation of osteoclastic phenotype in mouse bone marrow cultures using bone resorption and calcitonin receptors (CTR) as markers of osteoclastic differentiation. We found that PGE2 (10{sup {minus} 6}-10{sup {minus} 9} M) and PGE1 (10{sup {minus} 6} - 10{sup {minus} 7} M) induced a significant increase in CTR-positive cell numbers, to levels five to eight times those seen in controls and similar to the number induced by 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). Bone resorption was increased (10{sup {minus} 7} M PGE2 and 10{sup {minus} 6} M PGE1) in association with the increased CTR-positive cell numbers, suggesting that the PG also induced resorptive function. 1,25-(OH)2D3 increased both the number of CTR-positive cells and the extent of resorption per cell; the additional presence of PG did not affect the number of CTR-positive cells but did reduce bone resorption compared with 1,25-(OH)2D3 alone. PGF2 alpha had no significant effect on CTR-positive cell induction or bone resorption. The results suggest that PGE1 and E2 induce osteoclastic differentiation in mouse bone marrow cultures and inhibit the function of the osteoclasts thus formed.

  18. Biochemical Bone Turnover Markers and Osteoporosis in Older Men: Where Are We?

    Directory of Open Access Journals (Sweden)

    Pawel Szulc

    2011-01-01

    Full Text Available In men aged less than 60, the association of serum and urinary levels of biochemical bone turnover markers (BTMs and bone mineral density (BMD is weak or not significant. After this age, higher BTM levels are correlated weakly, but significantly, with lower BMD and faster bone loss. Limited data from the cohort studies suggest that BTM measurement does not improve the prediction of fragility fractures in older men in comparison with age, BMD, history of falls and fragility fractures. Testosterone replacement therapy (TRT decreases bone resorption. During TRT, bone formation markers slightly increase (direct effect on osteoblasts, then decrease (slowdown of bone turnover. Bisphosphonates (alendronate, risedronate, ibandronate, zoledronate induce a rapid decrease in bone resorption followed by a milder decrease in bone formation. In men receiving antiresorptive therapy for prostate cancer, zoledronate, denosumab and toremifene decrease significantly levels of bone resorption and bone formation markers. Teriparatide induced a rapid increase in serum concentrations of bone formation markers followed by an increase in bone resorption. We need more studies on the utility of BTM measurement for the improvement of the persistence and adherence to the anti-osteoporotic treatment in men.

  19. Sex steroids and bone.

    Science.gov (United States)

    Manolagas, S C; Kousteni, S; Jilka, R L

    2002-01-01

    The adult skeleton is periodically remodeled by temporary anatomic structures that comprise juxtaposed osteoclast and osteoblast teams and replace old bone with new. Estrogens and androgens slow the rate of bone remodeling and protect against bone loss. Conversely, loss of estrogen leads to increased rate of remodeling and tilts the balance between bone resorption and formation in favor of the former. Studies from our group during the last 10 years have elucidated that estrogens and androgens decrease the number of remodeling cycles by attenuating the birth rate of osteoclasts and osteoblasts from their respective progenitors. These effects result, in part, from the transcriptional regulation of genes responsible for osteoclastogenesis and mesenchymal cell replication and/or differentiation and are exerted through interactions of the ligand-activated receptors with other transcription factors. However, increased remodeling alone cannot explain why loss of sex steroids tilts the balance of resorption and formation in favor of the former. Estrogens and androgens also exert effects on the lifespan of mature bone cells: pro-apoptotic effects on osteoclasts but anti-apoptotic effects on osteoblasts and osteocytes. These latter effects stem from a heretofore unexpected function of the classical "nuclear" sex steroid receptors outside the nucleus and result from activation of a Src/Shc/extracellular signal-regulated kinase signal transduction pathway probably within preassembled scaffolds called caveolae. Strikingly, estrogen receptor (ER) alpha or beta or the androgen receptor can transmit anti-apoptotic signals with similar efficiency, irrespective of whether the ligand is an estrogen or an androgen. More importantly, these nongenotropic, sex-nonspecific actions are mediated by the ligand-binding domain of the receptor and can be functionally dissociated from transcriptional activity with synthetic ligands. Taken together, these lines of evidence strongly suggest that

  20. Vascularized tail bone grafts in rats.

    Science.gov (United States)

    Sempuku, T; Tamai, S; Mizumoto, S; Yajima, H

    1993-03-01

    A new experimental model for vascularized corticocancellous bone grafts was established by investigation of vascular anatomy of the tail in 15 adult Fischer 344 rats and determination of the viability of vascularized tail bone grafts into the abdominal wall in 22 7-week-old rats. The tail bones of 40 rats were then raised on the pedicle of the caudal artery and its venae comitantes, transferred to a resected portion in the femur, and observed for 16 weeks. The vascularized graft showed marked reactive periosteal bone formation during the first and second weeks following transfer, and thereafter, the graft continued to show active bone formation. In transverse section, the sharp processes became rounded. In the cancellous bone, both bone resorption and bone formation were noticeably activated early after transfer, although resorption predominated and the amount of the cancellous bone consequently diminished. The nonvascularized grafts showed "creeping substitution." The results suggest that morphologic adaptation occurs if living (i.e., vascularized) tail bones are transferred to long-bone femurs.

  1. Bone remodeling as a spatial evolutionary game.

    Science.gov (United States)

    Ryser, Marc D; Murgas, Kevin A

    2017-04-07

    Bone remodeling is a complex process involving cell-cell interactions, biochemical signaling and mechanical stimuli. Early models of the biological aspects of remodeling were non-spatial and focused on the local dynamics at a fixed location in the bone. Several spatial extensions of these models have been proposed, but they generally suffer from two limitations: first, they are not amenable to analysis and are computationally expensive, and second, they neglect the role played by bone-embedded osteocytes. To address these issues, we developed a novel model of spatial remodeling based on the principles of evolutionary game theory. The analytically tractable framework describes the spatial interactions between zones of bone resorption, bone formation and quiescent bone, and explicitly accounts for regulation of remodeling by bone-embedded, mechanotransducing osteocytes. Using tools from the theory of interacting particle systems we systematically classified the different dynamic regimes of the spatial model and identified regions of parameter space that allow for global coexistence of resorption, formation and quiescence, as observed in physiological remodeling. In coexistence scenarios, three-dimensional simulations revealed the emergence of sponge-like bone clusters. Comparison between spatial and non-spatial dynamics revealed substantial differences and suggested a stabilizing role of space. Our findings emphasize the importance of accounting for spatial structure and bone-embedded osteocytes when modeling the process of bone remodeling. Thanks to the lattice-based framework, the proposed model can easily be coupled to a mechanical model of bone loading.

  2. Management of Root Resorption Using Chemical Agents: A Review

    Science.gov (United States)

    Mohammadi, Zahed; C. Cehreli, Zafer; Shalavi, Sousan; Giardino, Luciano; Palazzi, Flavio; Asgary, Saeed

    2016-01-01

    Root resorption (RR) is defined as the loss of dental hard tissues because of clastic activity inside or outside of tooth the root. In the permanent dentition, RR is a pathologic event; if untreated, it might result in the premature loss of the affected tooth. Several hypotheses have been suggested as the mechanisms of root resorption such as absence of the remnants of Hertwig's epithelial root sheath (HERS) and the absence of some intrinsic factors in cementum and predentin such as amelogenin or osteoprotegerin (OPG). It seems that a barrier is formed by the less-calcified intermediate cementum or the cementodentin junction that prevents external RR. There are several chemical strategies to manage root resorption. The purpose of this paper was to review several chemical agents to manage RR such as tetracycline, sodium hypochlorite, acids (citric acid, phosphoric acid, ascorbic acid and hydrochloric acid), acetazolamide, calcitonin, alendronate, fluoride, Ledermix and Emdogain. PMID:26843869

  3. [Root resorption associated to orthodontic treatment: a clinical case].

    Science.gov (United States)

    Houb-Dine, Afaf; Rerhrhaye, Mariam; Ismaili, Zouheir; Rerhrhaye, Wiam

    2011-12-01

    Root resorption associated to orthodontic treatment is of multiple etiologies and a non intentional iatrogenic side effect which exists in almost all the orthodontic treatment. This clinical case of an apparently healthy patient illustrates the occurrence during the orthodontic treatment of a root resorption interesting the left central incisor, victims of previous traumatism and presenting a moderate periodontal attachment loss. The orthodontic treatment was carried out with light and continuous forces and a per-orthodontic periodontal maintenance in respect of periodontal requirements. As soon as the root resorption on the left central incisive was diagnosed, the active orthodontic treatment was interrupted in order to stabilize the lesion and a regular clinical and radiological monitoring was established.

  4. An unusual case of idiopathic multiple invasive cervical resorption

    Directory of Open Access Journals (Sweden)

    Sathya Prakash Reddy Kesary

    2014-01-01

    Full Text Available Invasive cervical resorption is a rare form of root resorption, characterized by destruction of the cervical region of teeth resulting from the action of tooth resorbing cells. Being an asymptomatic condition, it is often discovered on routine radiographic examination. This multifactorial disease process can most commonly occur as a sequel to orthodontic treatment, dental trauma, bleaching procedures, and less commonly, as an outcome of segmental orthognathic surgery, periodontal root planning, tetracycline conditioning of the root canal, bruxism, transplantation of tooth, guided tissue regeneration, cementoenamel disjunction. In the absence of these predisposing factors, it can be labeled as ′idiopathic multiple cervical resorption′. This article describes the case of a medically fit Indian male, who displayed idiopathic invasive cervical resorption in multiple teeth.

  5. Bone Canopies in Pediatric Renal Osteodystrophy

    DEFF Research Database (Denmark)

    Pereira, Renata C; Levin Andersen, Thomas; Friedman, Peter A;

    2016-01-01

    Pediatric renal osteodystrophy (ROD) is characterized by changes in bone turnover, mineralization, and volume that are brought about by alterations in bone resorption and formation. The resorptive and formative surfaces on the cancellous bone are separated from the marrow cavity by canopies...... and their association with biochemical and bone histomorphometric parameters in 106 pediatric chronic kidney disease (CKD) patients (stage 2-5) across the spectrum of ROD. Canopies in CKD patients often appeared as thickened multilayered canopies, similar to previous reports in patients with primary hyperparathyroidism....... This finding contrasts with the thin appearance reported in healthy individuals with normal kidney function. Furthermore, canopies in pediatric CKD patients showed immunoreactivity to the PTH receptor (PTHR1) as well as to the receptor activator of nuclear factor kappa-B ligand (RANKL). The number of surfaces...

  6. Management of invasive cervical resorption in a maxillary central incisor.

    Science.gov (United States)

    Kumar, S Senthil; Kumar, N S Mohan; Karunakaran, J V; Nagendran, S

    2015-08-01

    Invasive cervical resorption is often not diagnosed properly, leading to improper treatment or unnecessary loss of the tooth structure. Early diagnosis and appropriate treatment are the keys to a successful outcome of therapy. Invasive cervical resorption is often seen in the cervical area of the tooth, but because it is initiated apical to the epithelial attachment, it can present anywhere in the root. In the early stages, it may be symmetrical, but larger lesions have the tendency to be asymmetrical. It can expand apically or coronally.

  7. Monosodium glutamate-sensitive hypothalamic neurons contribute to the control of bone mass

    Science.gov (United States)

    Elefteriou, Florent; Takeda, Shu; Liu, Xiuyun; Armstrong, Dawna; Karsenty, Gerard

    2003-01-01

    Using chemical lesioning we previously identified hypothalamic neurons that are required for leptin antiosteogenic function. In the course of these studies we observed that destruction of neurons sensitive to monosodium glutamate (MSG) in arcuate nuclei did not affect bone mass. However MSG treatment leads to hypogonadism, a condition inducing bone loss. Therefore the normal bone mass of MSG-treated mice suggested that MSG-sensitive neurons may be implicated in the control of bone mass. To test this hypothesis we assessed bone resorption and bone formation parameters in MSG-treated mice. We show here that MSG-treated mice display the expected increase in bone resorption and that their normal bone mass is due to a concomitant increase in bone formation. Correction of MSG-induced hypogonadism by physiological doses of estradiol corrected the abnormal bone resorptive activity in MSG-treated mice and uncovered their high bone mass phenotype. Because neuropeptide Y (NPY) is highly expressed in MSG-sensitive neurons we tested whether NPY regulates bone formation. Surprisingly, NPY-deficient mice had a normal bone mass. This study reveals that distinct populations of hypothalamic neurons are involved in the control of bone mass and demonstrates that MSG-sensitive neurons control bone formation in a leptin-independent manner. It also indicates that NPY deficiency does not affect bone mass.

  8. Impact of lanthanum carbonate on cortical bone in dialysis patients with adynamic bone disease.

    Science.gov (United States)

    Yajima, Aiji; Inaba, Masaaki; Tominaga, Yoshihiro; Tanaka, Motoko; Otsubo, Shigeru; Nitta, Kosaku; Ito, Akemi; Satoh, Shigeru

    2013-04-01

    Among the most serious problems in patients with chronic kidney disease (CKD) is fragility of cortical bone caused by cortical thinning and increased cortical porosity; the cortical fragility is sometimes irreversible, with fractures generally initiating from cortical bone. Therefore, development of treatments for problems of cortical bone is urgently desired. Cortical bone has the three surfaces, including the periosteal surface, intracortical spaces and endocortical surface. Bone turnover at the endocortical surface and intracortical resorption spaces are increased as compared with that at cancellous surface. Bone growth sometimes depends on apposition at the periosteal surface. We treated hyperphosphatemia in two hemodialysis patients with adynamic bone disease with 750-1500 mg/day of lanthanum carbonate, which is a non-calcium containing phosphate binder; the treatment resulted in a decrease of the serum phosphorus levels (P levels), without significant change of the serum intact parathyroid hormone levels. We now report that treatment of these patients with lanthanum carbonate increased mineralization of the periosteal surface, increased bone mass within the intracortical resorption spaces and increased mineralization of the minimodeling surface at the endocortical surface. In addition, woven bone volume in cortical bone was decreased and mineralization of bone units, namely, osteons, was increased. Although these findings were not observed across all surfaces of the cortical bone in the patients, it is expected that lanthanum carbonate would increase the cortical stability in CKD patients, with consequent reduction in the fracture rate in these patients.

  9. Bone pathology inpsoriatic arthritis

    Directory of Open Access Journals (Sweden)

    V. V. Badokin

    2007-01-01

    Full Text Available Objective. To study different variants of osteolysis in pts with psoriatic arthritis (PA and to reveal their relationship with other clinico-radiological features of joint damage. Material and methods. 370 pts with definite PA having different variants of joint damage were included. Radiological examination of bones and joints (in some cases large picture frame was performed. Morphological evaluation of synovial biopsies was done in 34 pts with PA and 10 pts with rheumatoid arthritis (RA. Results. Different types of osteolysis were revealed in 80 (21,6% pts. Osteolytic variant of joint damage was present in 29 pts. 33 pts had acral, 48 — intra-articular osteolysis and 16 - true bone atrophy. Frequency and intensity of bone resorption were associated with severity of PA. Acral osteolysis correlated with arthritis of distal interphalangeal joints and onychodystrophy. Intra-articular osteolysis was most often present in distal interphalangeal joints of hands and metacarpophalangeal joints (39,6% and 41,7% respectively. Characteristic feature of PA was combination of prominent resorption with formation of bone ankylosis and periosteal reaction. Ankylosis was present in 33,3% of pts with intra-articular osteolysis and in 60% of pts with combination of different osteolysis variants. Systemic reaction of microcirculation in synovial biopsies was most prominent in osteolytic variant: marked thickening of capillary and venule basal membrane with high level of acid phosphatase, increased capillary and precapillary blood flow with stasis features, vascular lymphocyte and macrophage infiltration, productive vasculitis with annular wall thickening, thrombovasculitis and villi deep layer sclerosis. Conclusion. Different variants of osteolysis show bone involvement in PA. Acral and intra- articular osteolysis association with bone ankylosis and periostitis proves their common pathogenetic entity.

  10. Probiotics protect mice from ovariectomy-induced cortical bone loss.

    Directory of Open Access Journals (Sweden)

    Claes Ohlsson

    Full Text Available The gut microbiota (GM modulates the hosts metabolism and immune system. Probiotic bacteria are defined as live microorganisms which when administered in adequate amounts confer a health benefit on the host and can alter the composition of the GM. Germ-free mice have increased bone mass associated with reduced bone resorption indicating that the GM also regulates bone mass. Ovariectomy (ovx results in bone loss associated with altered immune status. The purpose of this study was to determine if probiotic treatment protects mice from ovx-induced bone loss. Mice were treated with either a single Lactobacillus (L strain, L. paracasei DSM13434 (L. para or a mixture of three strains, L. paracasei DSM13434, L. plantarum DSM 15312 and DSM 15313 (L. mix given in the drinking water during 6 weeks, starting two weeks before ovx. Both the L. para and the L. mix treatment protected mice from ovx-induced cortical bone loss and bone resorption. Cortical bone mineral content was higher in both L. para and L. mix treated ovx mice compared to vehicle (veh treated ovx mice. Serum levels of the resorption marker C-terminal telopeptides and the urinary fractional excretion of calcium were increased by ovx in the veh treated but not in the L. para or the L. mix treated mice. Probiotic treatment reduced the expression of the two inflammatory cytokines, TNFα and IL-1β, and increased the expression of OPG, a potent inhibitor of osteoclastogenesis, in cortical bone of ovx mice. In addition, ovx decreased the frequency of regulatory T cells in bone marrow of veh treated but not probiotic treated mice. In conclusion, treatment with L. para or the L. mix prevents ovx-induced cortical bone loss. Our findings indicate that these probiotic treatments alter the immune status in bone resulting in attenuated bone resorption in ovx mice.

  11. Magnesium incorporation into β-TCP reduced its in vivo resorption by decreasing parathormone production.

    Science.gov (United States)

    Yassuda, Debora H; Costa, Neusa F M; Fernandes, Gustavo O; Alves, Gutemberg G; Granjeiro, José M; Soares, Glória de A

    2013-07-01

    Beta-tricalcium phosphate (β-TCP), one of the most widely used bioresorbable materials for bone therapy, can be doped with magnesium ions, generating β-TCMP. The objectives of this work were to evaluate, on a murine dental alveolus grafting model, the biocompatibility of β-TCP and β-TMCP granules by histomorphometric analysis, as well as the impact on plasmatic levels of receptor activator of nuclear factor κB ligand (RANK-L), osteoprotegerin (OPG), osteocalcin, osteopontin, and parathormone (PTH) during bone repair, using Luminex multiplexing technology. After grafting for 42 days, β-TCP grafted group presented higher bioresorption and induced more newly formed bone than β-TCMP (p TCP grafting also induced higher plasmatic levels of RANK-L, compared to β-TCMP and control (blood clot) groups at 21st day (p TCP by the 42nd day (p TCP group and attained a peak on the 21st day. In conclusion, β-TCP granules were more bioresorbable and osteogenic than β-TCMP granules, and the resorption of both materials might have been affected by osteoclastogenesis modulated by changes in the plasmatic levels of PTH and RANK-L.

  12. The effect of photobiomodulation on root resorption during orthodontic treatment.

    Science.gov (United States)

    Nimeri, Ghada; Kau, Chung H; Corona, Rachel; Shelly, Jeffery

    2014-01-01

    Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm(2) continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little's Irregularity Index (>2 mm) in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little's Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little's Irregularity Index and root resorption was detected.

  13. Mice deficient in 11beta-hydroxysteroid dehydrogenase type 1 lack bone marrow adipocytes, but maintain normal bone formation

    DEFF Research Database (Denmark)

    Justesen, Jeannette; Mosekilde, Lis; Holmes, Megan

    2004-01-01

    and regenerates active cortisol (corticosterone) from circulating inert 11-keto forms. The aim of the present study was to investigate the role of this intracrine activation of GCs on normal bone physiology in vivo using mice deficient in 11betaHSD1 (HSD1(-/-)). The HSD1(-/-) mice exhibited no significant changes...... in cortical or trabecular bone mass compared with wild-type (Wt) mice. Aged HSD1(-/-) mice showed age-related bone loss similar to that observed in Wt mice. Histomorphometric analysis showed similar bone formation and bone resorption parameters in HSD1(-/-) and Wt mice. However, examination of bone marrow...

  14. The effect of ovalbumin on orthodontic induced root resorption

    Directory of Open Access Journals (Sweden)

    Hosseinagha Aghili

    2013-01-01

    Full Text Available Background: This randomized trial was undertaken to investigate the effect of experimentally induced allergy on orthodontic induced root resorption. Materials and Methods: A total of 30 Wistar rats were divided randomly into test and control groups. Starting from the first 3 days, the rats in the test group were injected intra-peritoneally by 2 mg ovalbumin as allergen and 0.5 mg Alume as adjuvant. Afterward only allergen was injected once a week. The control group was injected by normal saline. After 21 days, Wistar immunoglobulin E was measured and peripheral matured eosinophil was counted. A total of 50 g nickel-titanium closed coil spring was ligated between right incisor and first molar. All animals were sacrificed after 14 days. The mesial root of the right and left first molar was dissected in a horizontal plane. The specimens were divided into four groups considering whether force and/or ovalbumin was applied or not. Root resorption was measured and compared among these groups. Repeated measures analysis of variance (ANOVA, and Bonferoni tests were used to analyze the data. The level of significance was determined at 0.05. Results: In general, the differences were insignificant (P > 0.05. As the only exception, the group in which both ovalbumin and force were applied had significantly more root resorption than the group in which neither force nor ovalbumin was applied (P < 0.001. Conclusion: Allergy may increase the susceptibility to root resorption. Application of light force, periodical monitoring of root resorption and control of allergy are advisable.

  15. Lanthanum carbonate stimulates bone formation in a rat model of renal insufficiency with low bone turnover.

    Science.gov (United States)

    Fumoto, Toshio; Ito, Masako; Ikeda, Kyoji

    2014-09-01

    Control of phosphate is important in the management of chronic kidney disease with mineral and bone disorder (CKD-MBD), for which lanthanum carbonate, a non-calcium phosphate-binding agent, has recently been introduced; however, it remains to be determined whether it has any beneficial or deleterious effect on bone remodeling. In the present study, the effects of lanthanum carbonate were examined in an animal model that mimics low turnover bone disease in CKD, i.e., thyroparathyroidectomized (TPTX) and 5/6 nephrectomized (NX) rats undergoing a constant infusion of parathyroid hormone (PTH) and thyroxine injections (TPTX-PTH-5/6NX). Bone histomorphometry at the second lumbar vertebra and tibial metaphysis revealed that both bone formation and resorption were markedly suppressed in the TPTX-PTH-5/6NX model compared with the sham-operated control group, and treatment with lanthanum carbonate was associated with the stimulation of bone formation but not an acceleration of bone resorption. Lanthanum treatment caused a robust stimulation of bone formation with an activation of osteoblasts on the endosteal surface of femoral diaphysis, leading to an increase in cortical bone volume. Thus, lanthanum carbonate has the potential to stimulate bone formation in cases of CKD-MBD with suppressed bone turnover.

  16. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor; Bone tumor - benign ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  17. Biochemical markers of bone metabolism reflect osteoclastic and osteoblastic activity in multiple myeloma

    DEFF Research Database (Denmark)

    Abildgaard, N; Glerup, H; Rungby, Jørgen;

    2000-01-01

    In order to evaluate the use of recently developed assays of bone metabolism in multiple myeloma we performed a histomorphometric study of bone biopsies in 16 myeloma patients. Furthermore, we measured the levels of interleukin-6 (IL-6), soluble IL-6 receptor (IL-6sR), IL-1beta, tumour necrosis...... factor (TNF) alpha, TNFbeta, and transforming growth factor (TGF) beta in marrow plasma aspirated from the biopsy area. MARKERS OF BONE RESORPTION: The N-terminal telopeptide of collagen I (Ntx) in urine showed a strong positive correlation with the dynamic histomorphometric indices of bone resorption (r......=0.68-0.72). Slightly weaker correlations were observed between the dynamic indices of bone resorption and the C-terminal telopeptide of collagen I (ICTP) in serum (r= 0.57-0.62) and deoxypyridinoline (Dpyr) in urine (r= 0.54), whereas urinary pyridinoline (Pyr) did not correlate...

  18. Seasonal Variation of Nutrient Resorption in Nine Canopy Trees of a Wet Tropical Forest

    Science.gov (United States)

    Wood, T. E.; Lawrence, D.

    2006-12-01

    Withdrawal of nutrients at the time of leaf abscission (nutrient resorption) is a nutrient conserving mechanism that could play an important role in stand-level nutrient economy. Currently data on nutrient resorption in wet tropical forests and on how this process varies temporally are sparse. We evaluated the N and P resorption efficiency of nine rain forest canopy tree species in both wet and dry season months. In addition, we measured short-term (bi-weekly) variation in nutrient resorption in the two dominant tree species, Pentaclethra macroloba and Laetia procera, over a 4-month period. We hypothesized that nutrient resorption would be more efficient during the dry season months and that resorption would be low during periods of high rainfall. Contrary to expectations, P resorption efficiency was higher in the wet season for four of the nine canopy tree species, while N resorption did not differ seasonally. The low dry season P resorption efficiency found in this study may be the result of drought stress during short periods of low rainfall, leading to incomplete nutrient resorption from senescing leaves. Nutrient resorption also varied significantly over the short-term. Both P and N resorption efficiency increased in P. macroloba and L. procera as the wet season progressed. The variability in resorption was not related to rainfall or temperature. Instead, the senesced leaf concentrations were a simple proportion of green leaf nutrient concentrations, with short punctuated periods of high resorption efficiency that may be reflective of species-specific phenological events, such as fruit and leaf production. The different timing of the seasonal increase in nutrient resorption between L. procera and P. macroloba supports this hypothesis, deserving of further study.

  19. Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography.

    Science.gov (United States)

    Xiao, W-L; Zhang, D-Z; Chen, X-J; Yuan, C; Xue, L-F

    2016-06-01

    Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis.

  20. Mechanisms of multiple myeloma bone disease

    Science.gov (United States)

    Galson, Deborah L; Silbermann, Rebecca; Roodman, G David

    2012-01-01

    Multiple myeloma is the second most common hematological malignancy and the most frequent cancer to involve the skeleton. Multiple myeloma bone disease (MMBD) is characterized by abnormal bone remodeling with dysfunction of both bone resorption and bone formation, and thus can be used as a paradigm for other inflammatory bone diseases, and the regulation of osteoclasts and osteoblasts in malignancy. Studies of MMBD have identified novel regulators that increase osteoclastogenesis and osteoclast function, repress osteoblast differentiation, increase angiogenesis, or permanently alter stromal cells. This review will discuss the current understanding of mechanisms of osteoclast and osteoblast regulation in MMBD, and therapeutic approaches currently in use and under development that target mediators of bone destruction and blockade of bone formation for myeloma patients, including new anabolic therapies. PMID:23951515

  1. Relationships among maxillofacial morphologies, bone properties, and bone metabolic markers in patients with jaw deformities.

    Science.gov (United States)

    Saito, D; Mikami, T; Oda, Y; Hasebe, D; Nishiyama, H; Saito, I; Kobayashi, T

    2016-08-01

    The aim of this study was to determine the relationships among bone properties, bone metabolic markers, and types of jaw deformity. The subjects were 55 female patients with jaw deformities. Skeletal morphology was examined using lateral cephalograms, and the patients were divided into three groups according to the type of anteroposterior skeletal pattern. Serum osteocalcin, bone alkaline phosphatase, and tartrate-resistant acid phosphatase isoform 5b, as well as deoxypyridinoline in urine, were measured as bone metabolic markers. Quantitative ultrasound (QUS) measurements were used to assess bone properties at the calcaneal bone. The bone volume and bone density of the condylar process were measured in 43 patients by computed tomography. There were no significant differences in bone metabolic markers and QUS parameters between the groups, although bone formation and resorption markers tended to be higher in patients with a protrusive mandible. On the other hand, patients with mandibular retrusion had a higher tendency to have small and dense condylar processes. In conclusion, the results suggest that growth depression or a degenerative change in the mandibular condyle is involved in the pathogenesis of mandibular retrusion, although risk factors for progressive condylar resorption were not determined.

  2. Multiple idiopathic external and internal resorption: Case report with cone-beam computed tomography findings

    Energy Technology Data Exchange (ETDEWEB)

    Celikten, Berkan; Uzuntas, Ceren Feriha; Kurt, Hakan [Faculty of Dentistry, Ankara University, Ankara (Turkmenistan)

    2014-12-15

    Root resorption is loss of dental hard tissue as a result of clastic activities. The dental hard tissue of permanent teeth does not normally undergo resorption, except in cases of inflammation or trauma. However, there are rare cases of tooth resorption of an unknown cause, known as 'idiopathic root resorption.' This report would discuss a rare case of multiple idiopathic resorption in the permanent maxillary and mandibular teeth of an otherwise healthy 36-year-old male patient. In addition to a clinical examination, the patient was imaged using conventional radiography and cone-beam computed tomography (CBCT). The examinations revealed multiple external and internal resorption of the teeth in all four quadrants of the jaws with an unknown cause. Multiple root resorption is a rare clinical phenomenon that should be examined using different radiographic modalities. Cross-sectional CBCT is useful in the diagnosis and examination of such lesions.

  3. Multiple idiopathic external and internal resorption: Case report with cone-beam computed tomography findings.

    Science.gov (United States)

    Celikten, Berkan; Uzuntas, Ceren Feriha; Kurt, Hakan

    2014-12-01

    Root resorption is loss of dental hard tissue as a result of clastic activities. The dental hard tissue of permanent teeth does not normally undergo resorption, except in cases of inflammation or trauma. However, there are rare cases of tooth resorption of an unknown cause, known as "idiopathic root resorption." This report would discuss a rare case of multiple idiopathic resorption in the permanent maxillary and mandibular teeth of an otherwise healthy 36-year-old male patient. In addition to a clinical examination, the patient was imaged using conventional radiography and cone-beam computed tomography (CBCT). The examinations revealed multiple external and internal resorption of the teeth in all four quadrants of the jaws with an unknown cause. Multiple root resorption is a rare clinical phenomenon that should be examined using different radiographic modalities. Cross-sectional CBCT is useful in the diagnosis and examination of such lesions.

  4. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis.

  5. Bone modeling and remodeling: potential as therapeutic targets for the treatment of osteoporosis.

    Science.gov (United States)

    Langdahl, Bente; Ferrari, Serge; Dempster, David W

    2016-12-01

    The adult skeleton is renewed by remodeling throughout life. Bone remodeling is a process where osteoclasts and osteoblasts work sequentially in the same bone remodeling unit. After the attainment of peak bone mass, bone remodeling is balanced and bone mass is stable for one or two decades until age-related bone loss begins. Age-related bone loss is caused by increases in resorptive activity and reduced bone formation. The relative importance of cortical remodeling increases with age as cancellous bone is lost and remodeling activity in both compartments increases. Bone modeling describes the process whereby bones are shaped or reshaped by the independent action of osteoblast and osteoclasts. The activities of osteoblasts and osteoclasts are not necessarily coupled anatomically or temporally. Bone modeling defines skeletal development and growth but continues throughout life. Modeling-based bone formation contributes to the periosteal expansion, just as remodeling-based resorption is responsible for the medullary expansion seen at the long bones with aging. Existing and upcoming treatments affect remodeling as well as modeling. Teriparatide stimulates bone formation, 70% of which is remodeling based and 20-30% is modeling based. The vast majority of modeling represents overflow from remodeling units rather than de novo modeling. Denosumab inhibits bone remodeling but is permissive for modeling at cortex. Odanacatib inhibits bone resorption by inhibiting cathepsin K activity, whereas modeling-based bone formation is stimulated at periosteal surfaces. Inhibition of sclerostin stimulates bone formation and histomorphometric analysis demonstrated that bone formation is predominantly modeling based. The bone-mass response to some osteoporosis treatments in humans certainly suggests that nonremodeling mechanisms contribute to this response and bone modeling may be such a mechanism. To date, this has only been demonstrated for teriparatide, however, it is clear that

  6. Experimental study of diamond resorption during mantle metasomatism

    Science.gov (United States)

    Fedorchuk, Yana; Schmidt, Max W.; Liebske, Christian

    2014-05-01

    Many of kimberlite-derived diamonds are partially dissolved to various degree but show similar resorption style. This resorption style has been observed in experiments with aqueous fluid at the conditions corresponding to kimberlite emplacement (1-2 GPa). At the same time, each diamond population has more than ten percent of diamond crystals with several drastically different resorption styles, which have not been observed in experiments, and may represent partial dissolution of diamonds during metasomatism in different mantle domains. Metasomatic processes modify the composition of subcratonic mantle, may trigger the formation of kimberlite magma, and result in the growth and partial dissolution of diamonds. Composition of metasomatic agents as constrained from studies of the reaction rims on mantle minerals (garnet, clinopyroxene) and experimental studies vary between carbonatitic melt, aqueous silicate melt, and CHO fluid. However, complex chemical pattern of mantle minerals and estimates of redox regime in subcratonic mantle allow different interpretations. Here we explore diamond dissolution morphology as an indicator of the composition of mantle metasomatic agents. Towards this end we examine diamond dissolution morphologies developed in experiments at the conditions of mantle metasomatism in different reacting media and compare them to the mantle-derived dissolution features of natural diamonds. The experiments were conducted in multi-anvil (Walker-Type) apparatus at 6 GPa and 1200-1500oC. Dissolution morphology of natural octahedral diamond crystals (0.5 mg) was examined in various compositions in synthetic system MgO-CaO- SiO2-CO2-H2O. The runs had the following phases present: solid crystals with fluid (various ratio of H2O-CO2-SiO2, and in the air), carbonate melt, carbonate-silicate melt, and carbonate melt with CHO fluid. Experiments produced three different styles of diamond resorption. In the presence of a fluid phase with variable proportions of H2O

  7. Root resorption related to orthodontics and other factors: a review of the literature.

    Science.gov (United States)

    Rupp, R

    1995-09-01

    Each patient (and parents or guardian) should be clearly informed that there is a real possibility of one or more teeth undergoing root resorption during orthodontic procedures. They should sign an Information and Consent Form arranged by the dentist that they understand these risks before treatment is begun. Open bite cases possess significantly great degrees of resorption. Since trauma is closely associated with root resorption, the patient (and parents or guardian) should be questioned concerning previous traumatic occurrences that involved blows or accidents involving the teeth. Periapical radiographs are an important part of orthodontic records. They are useful to compare pretreatment and posttreatment root resorption. Maxillary incisors are affected more frequently and to a greater degree than the rest of the teeth during active treatment. Also, root resorption of the upper incisors during the initial 6-9 months of treatment with fixed appliances gives a high risk for continued resorption during the subsequent treatment. Therefore, it would be prudent to take periapical radiographs periodically during treatment. When root resorption is detected during active treatment, a decision must be made as to whether to continue, modify or discontinue the treatment. Extremely heavy forces should be avoided, since they have been shown to produce greater resorption activity. The ectopic eruption of canines causes a significant number of resorptions in lateral incisors. Habits adversely affect root resorption and should be eliminated if possible. Pathological lesions increase the risk of resorption. Periodontal disease increases the risk of resorption. The practitioner contemplating doing orthodontics should be cognizant of the above factors in evaluating the risk of root resorption. Patients (and parents or guardians) should be made clearly aware that any type of orthodontic treatment carries with it the risk of root tip blunting or resorption during orthodontic therapy.

  8. Anti-resorptive effect of pilose antler blood (Cervus nippon Temminck) in ovariectomized rats.

    Science.gov (United States)

    Yang, Jian-Hong; Cao, Yi; Wang, Rui-Lin; Fei, Yu-Rong; Zhang, Hui; Feng, Pu; Liu, Jing

    2010-06-01

    Anti-bone resorption activity of pilose antler blood (Cervus nippon Temminck) were evaluated in ovariectomized Wistar rats. The rats were randomly divided into sham operated group (SHAM), ovariectomized group (OVX) and pilose antler blood treated group. The ovariectomized rats were treated with pilose antler blood orally in 4000 microl/kg daily doses for 10 weeks. Compared with SHAM group, serum 17 beta-estradiol level decreased significantly and osteocalcin level increased significantly in OVX group, indicating successful model of osteoporosis. The experiments showed that the bone mineral density of the lumbar spine and left femur in OVX group decreased remarkably compared to SHAM group but normalized by treatment with pilose antler blood. Additionally, serum levels of insulin-like growth factor-land testosterone were lower obviously in OVX group than those in SHAM group but preserved by pilose antler blood treatment. However, no obvious changes in serum levels of calcium, phosphorus, total alkaline phosphatase and osteoprotegerin were observed among three groups. These results suggested that administration of pilose antler blood was effective in alleviating osteoporosis in ovariectomized rats.

  9. A histological evaluation on osteogenesis and resorption of methotrexate-loaded calcium phosphate cement in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Li Dong; Yang Zhiping; Li Xin; Li Zhenfeng; Li Jianmin [Department of Orthopedics, Qilu Hospital of Shandong University, Shandong (China); Yang Jingyan, E-mail: yangzhiping@medmail.com.c [Department of Pathology, 2nd Affiliated Hospital of Shandong University, Shandong (China)

    2010-04-15

    In this study, we investigated the resorption of in vivo methotrexate-loaded calcium phosphate cement (MTX-CPC) implants and their effect on osteogenesis. MTX-CPC implants containing 1% methotrexate (MTX) (weight/weight) were preset and implanted into the femoral condyle of rabbits. Calcium phosphate cement (CPC) without MTX was used as the control. The femurs were harvested at day 1 and at 1, 3 and 6 months after implantation and radiological examination were performed. Decalcified sections were examined by hematoxylin and eosin (HE) staining, alkaline phosphatase (ALPase) immunohistochemistry and tartrate-resistant acid phosphatase (TRAPase) enzyme histochemistry. Then, we performed histomorphometric analysis, including determination of the percentage of newly formed bone and osteoblast and osteoclast counts. The results indicated that MTX-CPC implants were biocompatible, biodegradable and osteoconducive. However, MTX release from the implantation site inhibited osteogenesis in the initial period; this inhibition weakened with time, and no difference was observed between CPC and MTX-CPC at 6 months after implantation. Hence, MTX-CPC is an excellent material for filling defects and can be used for preparing effective drug delivery systems to achieve local control of invasive bone tumors.

  10. Connecting mechanics and bone cell activities in the bone remodeling process: an integrated finite element modeling.

    Science.gov (United States)

    Hambli, Ridha

    2014-01-01

    Bone adaptation occurs as a response to external loadings and involves bone resorption by osteoclasts followed by the formation of new bone by osteoblasts. It is directly triggered by the transduction phase by osteocytes embedded within the bone matrix. The bone remodeling process is governed by the interactions between osteoblasts and osteoclasts through the expression of several autocrine and paracrine factors that control bone cell populations and their relative rate of differentiation and proliferation. A review of the literature shows that despite the progress in bone remodeling simulation using the finite element (FE) method, there is still a lack of predictive models that explicitly consider the interaction between osteoblasts and osteoclasts combined with the mechanical response of bone. The current study attempts to develop an FE model to describe the bone remodeling process, taking into consideration the activities of osteoclasts and osteoblasts. The mechanical behavior of bone is described by taking into account the bone material fatigue damage accumulation and mineralization. A coupled strain-damage stimulus function is proposed, which controls the level of autocrine and paracrine factors. The cellular behavior is based on Komarova et al.'s (2003) dynamic law, which describes the autocrine and paracrine interactions between osteoblasts and osteoclasts and computes cell population dynamics and changes in bone mass at a discrete site of bone remodeling. Therefore, when an external mechanical stress is applied, bone formation and resorption is governed by cells dynamic rather than adaptive elasticity approaches. The proposed FE model has been implemented in the FE code Abaqus (UMAT routine). An example of human proximal femur is investigated using the model developed. The model was able to predict final human proximal femur adaptation similar to the patterns observed in a human proximal femur. The results obtained reveal complex spatio-temporal bone

  11. Effect of Epimedium-derived Phytoestrogen on Bone Turnover and Bone Microarchitecture in OVX-induced Osteoporotic Rats

    Institute of Scientific and Technical Information of China (English)

    Songlin PENG; Renyun XIA; Huang FANG; Feng LI; Anmin CHEN; Ge ZHANG; Ling QIN

    2008-01-01

    To investigate the preventive effect of epimedium-defivod phytoestrogen (PE) on osteoporosis induced by ovariectomy (OVX) in rats, 11-month-old female Wistar rats were randomly di- vided into Sham, OVX and PE groups. One week after OVX, daily oral administration of PE (0.4 g·kg-1·day·-1) started in PE group, and rats in Sham and OVX groups were given vehicle accordingly. The administrations lasted for 12 weeks. The biological markers including serum osteocalcin (OC) and urinary deoxypyridinoline (DPD) for bone turnover were evaluated at the end of the 12th week. On the 13th week, all the rats were sacrificed. The right proximal tibiae were removed, subjected to micro CT for determination of trabeonlar bone structure and then bone histomorphometry was per- formed to assess bone remodeling. The OVX rats were in a high bone turnover status as evidenced by increased bone formation markers and bone resorption markers. Treatment with PE could suppress the high bone turnover rate in OVX rats. Micro CT data revealed that PE treatment could ameliorate the deterioration of the micro-architecture of proximal tibiae induced by OVX, as demonstrated by greater bone volume, increased trabecular thickness and less trahecular separation in PE group in comparison with OVX group. The static and dynamic parameters of bone histomorphometry indi- cated that there were significant increases in bone formation variables and significant decreases in bone resorption variables between PE and OVX groups. The findings suggest that PE has a beneficial effect on trabecular bone in OVX rat model and this effect is possibly associated with stimulation of bone formation as well as inhibition of bone resorption.

  12. Peptide-induced de novo bone formation after tooth extraction prevents alveolar bone loss in a murine tooth extraction model.

    Science.gov (United States)

    Arai, Yuki; Aoki, Kazuhiro; Shimizu, Yasuhiro; Tabata, Yasuhiko; Ono, Takashi; Murali, Ramachandran; Mise-Omata, Setsuko; Wakabayashi, Noriyuki

    2016-07-05

    Tooth extraction causes bone resorption of the alveolar bone volume. Although recombinant human bone morphogenetic protein 2 (rhBMP-2) markedly promotes de novo bone formation after tooth extraction, the application of high-dose rhBMP-2 may induce side effects, such as swelling, seroma, and an increased cancer risk. Therefore, reduction of the necessary dose of rhBMP-2 which can still obtain sufficient bone mass is necessary by developing a new osteogenic reagent. Recently, we showed that the systemic administration of OP3-4 peptide, which was originally designed as a bone resorption inhibitor, had osteogenic ability both in vitro and in vivo. This study evaluated the ability of the local application of OP3-4 peptide to promote bone formation in a murine tooth extraction model with a very low-dose of BMP. The mandibular incisor was extracted from 10-week-old C57BL6/J male mice and a gelatin hydrogel containing rhBMP-2 with or without OP3-4 peptide (BMP/OP3-4) was applied to the socket of the incisor. Bone formation inside the socket was examined radiologically and histologically at 21 days after the extraction. The BMP/OP3-4-group showed significant bone formation inside the mandibular extraction socket compared to the gelatin-hydrogel-carrier-control group or rhBMP-2-applied group. The BMP/OP3-4-applied mice showed a lower reduction of alveolar bone and fewer osteoclast numbers, suggesting that the newly formed bone inside the socket may prevent resorption of the cortical bone around the extraction socket. Our data revealed that OP3-4 peptide promotes BMP-mediated bone formation inside the extraction socket of mandibular bone, resulting in preservation from the loss of alveolar bone.

  13. Spontaneous resorption of sub-retinal cortical lens material

    Directory of Open Access Journals (Sweden)

    Salil S Gadkari

    2014-01-01

    Full Text Available We report a rare case of retained sub-retinal cortical material, which underwent spontaneous resorption. Patient presented with a left eye traumatic retinal detachment with a large retinal tear and posteriorly dislocated cataractous lens. Vitrectomy, lensectomy, silicone oil injection, and endolaser were performed. A good visual result was achieved. The report draws attention to this condition and highlights possible technique for minimizing risk of this complication in similar cases.

  14. Rhus javanica Gall Extract Inhibits the Differentiation of Bone Marrow-Derived Osteoclasts and Ovariectomy-Induced Bone Loss

    Directory of Open Access Journals (Sweden)

    Tae-Ho Kim

    2016-01-01

    Full Text Available Inhibition of osteoclast differentiation and bone resorption is a therapeutic strategy for the management of postmenopausal bone loss. This study investigated the effects of Rhus javanica (R. javanica extracts on bone marrow cultures to develop agents from natural sources that may prevent osteoclastogenesis. Extracts of R. javanica (eGr cocoons spun by Rhus javanica (Bell. Baker inhibited the osteoclast differentiation and bone resorption. The effects of aqueous extract (aeGr or 100% ethanolic extract (eeGr on ovariectomy- (OVX- induced bone loss were investigated by various biochemical assays. Furthermore, microcomputed tomography (µCT was performed to study bone remodeling. Oral administration of eGr (30 mg or 100 mg/kg/day for 6 weeks augmented the inhibition of femoral bone mineral density (BMD, bone mineral content (BMC, and other factors involved in bone remodeling when compared to OVX controls. Additionally, eGr slightly decreased bone turnover markers that were increased by OVX. Therefore, it may be suggested that the protective effects of eGr could have originated from the suppression of OVX-induced increase in bone turnover. Collectively, the findings of this study indicate that eGr has potential to activate bone remodeling by inhibiting osteoclast differentiation and bone loss.

  15. Severe destruction of the temporomandibular joint with complete resorption of the condyle associated with synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome.

    Science.gov (United States)

    Kodama, Yasumitsu; Tanaka, Ray; Kurokawa, Akira; Ohnuki, Hisashi; Sultana, Sara; Hayashi, Takafumi; Iizuka, Tateyuki; Takagi, Ritsuo

    2013-08-01

    The synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome consists of a combination of inflammatory bone disorders and dermatologic pathology. Bone lesions as a form of diffuse sclerosing osteomyelitis in the mandible occur in the posterior body and ramus. Bone lesions rarely spread to the temporomandibular joint (TMJ) where ankylosis may result. Herein we present an unusual case of SAPHO syndrome with TMJ involvement in which severe destruction of the TMJ occurred. We observed an extension of the invasive soft tissue lesion into the infratemporal fossa from the TMJ with complete resorption of the condyle. In contrast to other previously reported cases, in our case the condyle was strongly suspected as the primary site of the bone lesion with subsequent extension to the ramus and infratemporal fossa. The destructive nature and related symptoms resembled a malignant tumor.

  16. Chondromodulin I Is a Bone Remodeling Factor

    OpenAIRE

    NAKAMICHI, YUKO; Shukunami, Chisa; Yamada, Takashi; Aihara, Ken-ichi; Kawano, Hirotaka; Sato, Takashi; Nishizaki, Yuriko; Yamamoto, Yoko; Shindo, Masayo; Yoshimura, Kimihiro; Nakamura, Takashi; Takahashi, Naoyuki; Kawaguchi, Hiroshi; Hiraki, Yuji; Kato, Shigeaki

    2003-01-01

    Chondromodulin I (ChM-I) was supposed from its limited expression in cartilage and its functions in cultured chondrocytes as a major regulator in cartilage development. Here, we generated mice deficient in ChM-I by targeted disruption of the ChM-I gene. No overt abnormality was detected in endochondral bone formation during embryogenesis and cartilage development during growth stages of ChM-I−/− mice. However, a significant increase in bone mineral density with lowered bone resorption with re...

  17. Compression-absorption (resorption) refrigerating machinery. Modeling of reactors; Machine frigorifique a compression-absorption (resorption). Modelisation des reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Lottin, O.; Feidt, M.; Benelmir, R. [LEMTA-UHP Nancy-1, 54 - Vandoeuvre-les-Nancy (France)

    1997-12-31

    This paper is a series of transparencies presenting a comparative study of the thermal performances of different types of refrigerating machineries: di-thermal with vapor compression, tri-thermal with moto-compressor, with ejector, with free piston, adsorption-type, resorption-type, absorption-type, compression-absorption-type. A prototype of ammonia-water compression-absorption heat pump is presented and modeled. (J.S.)

  18. Cannabinoids and bone: friend or foe?

    Science.gov (United States)

    Idris, Aymen I; Ralston, Stuart H

    2010-10-01

    The endocannabinoid system is recognized to play an important role in regulating a variety of physiological processes, including appetite control and energy balance, pain perception, and immune responses. The endocannabinoid system has also recently been implicated in the regulation of bone metabolism. Endogenously produced cannabinoids are hydrophobic molecules derived from hydrolysis of membrane phospholipids. These substances, along with plant-derived and synthetic cannabinoids, interact with the type 1 (CB(1)) and 2 (CB(2)) cannabinoid receptors and the GPR55 receptor to regulate cellular function through a variety of signaling pathways. Endocannabinoids are produced in bone, but the mechanisms that regulate their production are unclear. Skeletal phenotyping of mice with targeted inactivation of cannabinoid receptors and pharmacological studies have shown that cannabinoids play a key role in the regulation of bone metabolism. Mice with CB(1) deficiency have high peak bone mass as a result of an osteoclast defect but develop age-related osteoporosis as a result of impaired bone formation and accumulation of bone marrow fat. Mice with CB(2) deficiency have relatively normal peak bone mass but develop age-related osteoporosis as a result of increased bone turnover with uncoupling of bone resorption from bone formation. Mice with GPR55 deficiency have increased bone mass as a result of a defect in the resorptive activity of osteoclasts, but bone formation is unaffected. Cannabinoids are also produced within synovial tissues, and preclinical studies have shown that cannabinoid receptor ligands are effective in the treatment of inflammatory arthritis. These data indicate that cannabinoid receptors and the enzymes responsible for ligand synthesis and breakdown play important roles in bone remodeling and in the pathogenesis of joint disease.

  19. Effect of load on the bone around bone-anchored amputation prostheses.

    Science.gov (United States)

    Stenlund, Patrik; Trobos, Margarita; Lausmaa, Jukka; Brånemark, Rickard; Thomsen, Peter; Palmquist, Anders

    2016-06-24

    Osseointegrated transfemoral amputation prostheses have proven successful as an alternative method to the conventional socket-type prostheses. The method improves prosthetic use and thus increases the demands imposed on the bone-implant system. The hypothesis of the present study was that the loads applied to the bone-anchored implant system of amputees would result in locations of high stress and strain transfer to the bone tissue and thus contribute to complications such as unfavourable bone remodeling and/or elevated inflammatory response and/or compromised sealing function at the tissue-abutment interface. In the study, site-specific loading measurements were made on amputees and used as input data in finite element analyses to predict the stress and strain distribution in the bone tissue. Furthermore, a tissue sample retrieved from a patient undergoing implant revision was characterized in order to evaluate the long-term tissue response around the abutment. Within the limit of the evaluated bone properties in the present experiments, it is concluded that the loads applied to the implant system may compromise the sealing function between the bone and the abutment, contributing to resorption of the bone in direct contact with the abutment at the most distal end. This was supported by observations in the retrieved clinical sample of bone resorption and the formation of a soft tissue lining along the abutment interface. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

  20. Responses of plant nutrient resorption to phosphorus addition in freshwater marsh of Northeast China.

    Science.gov (United States)

    Mao, Rong; Zeng, De-Hui; Zhang, Xin-Hou; Song, Chang-Chun

    2015-01-29

    Anthropogenic activities have increased phosphorus (P) inputs to most aquatic and terrestrial ecosystems. However, the relationship between plant nutrient resorption and P availability is still unclear, and much less is known about the underlying mechanisms. Here, we used a multi-level P addition experiment (0, 1.2, 4.8, and 9.6 g P m(-2) year(-1)) to assess the effect of P enrichment on nutrient resorption at plant organ, species, and community levels in a freshwater marsh of Northeast China. The response of nutrient resorption to P addition generally did not vary with addition rates. Moreover, nutrient resorption exhibited similar responses to P addition across the three hierarchical levels. Specifically, P addition decreased nitrogen (N) resorption proficiency, P resorption efficiency and proficiency, but did not impact N resorption efficiency. In addition, P resorption efficiency and proficiency were linearly related to the ratio of inorganic P to organic P and organic P fraction in mature plant organs, respectively. Our findings suggest that the allocation pattern of plant P between inorganic and organic P fractions is an underlying mechanism controlling P resorption processes, and that P enrichment could strongly influence plant-mediated biogeochemical cycles through altered nutrient resorption in the freshwater wetlands of Northeast China.

  1. Responses of plant nutrient resorption to phosphorus addition in freshwater marsh of Northeast China

    Science.gov (United States)

    Mao, Rong; Zeng, De-Hui; Zhang, Xin-Hou; Song, Chang-Chun

    2015-01-01

    Anthropogenic activities have increased phosphorus (P) inputs to most aquatic and terrestrial ecosystems. However, the relationship between plant nutrient resorption and P availability is still unclear, and much less is known about the underlying mechanisms. Here, we used a multi-level P addition experiment (0, 1.2, 4.8, and 9.6 g P m-2 year-1) to assess the effect of P enrichment on nutrient resorption at plant organ, species, and community levels in a freshwater marsh of Northeast China. The response of nutrient resorption to P addition generally did not vary with addition rates. Moreover, nutrient resorption exhibited similar responses to P addition across the three hierarchical levels. Specifically, P addition decreased nitrogen (N) resorption proficiency, P resorption efficiency and proficiency, but did not impact N resorption efficiency. In addition, P resorption efficiency and proficiency were linearly related to the ratio of inorganic P to organic P and organic P fraction in mature plant organs, respectively. Our findings suggest that the allocation pattern of plant P between inorganic and organic P fractions is an underlying mechanism controlling P resorption processes, and that P enrichment could strongly influence plant-mediated biogeochemical cycles through altered nutrient resorption in the freshwater wetlands of Northeast China.

  2. Using Natural Stable Calcium Isotopes to Rapidly Assess Changes in Bone Mineral Balance Using a Bed Rest Model to Induce Bone Loss

    Science.gov (United States)

    Morgan, J. L. L.; Skulan, J. L.; Gordon, G. E.; Smith, Scott M.; Romaniello, S. J.; Anbar, A. D.

    2012-01-01

    Metabolic bone diseases like osteoporosis result from the disruption of normal bone mineral balance (BMB) resulting in bone loss. During spaceflight astronauts lose substantial bone. Bed rest provides an analog to simulate some of the effects of spaceflight; including bone and calcium loss and provides the opportunity to evaluate new methods to monitor BMB in healthy individuals undergoing environmentally induced-bone loss. Previous research showed that natural variations in the Ca isotope ratio occur because bone formation depletes soft tissue of light Ca isotopes while bone resorption releases that isotopically light Ca back into soft tissue (Skulan et al, 2007). Using a bed rest model, we demonstrate that the Ca isotope ratio of urine shifts in a direction consistent with bone loss after just 7 days of bed rest, long before detectable changes in bone mineral density (BMD) occur. The Ca isotope variations tracks changes observed in urinary N-teleopeptide, a bone resorption biomarker. Bone specific alkaline phosphatase, a bone formation biomarker, is unchanged. The established relationship between Ca isotopes and BMB can be used to quantitatively translate the changes in the Ca isotope ratio to changes in BMD using a simple mathematical model. This model predicts that subjects lost 0.25 0.07% ( SD) of their bone mass from day 7 to day 30 of bed rest. Given the rapid signal observed using Ca isotope measurements and the potential to quantitatively assess bone loss; this technique is well suited to study the short-term dynamics of bone metabolism.

  3. WHI-131 Promotes Osteoblast Differentiation and Prevents Osteoclast Formation and Resorption in Mice.

    Science.gov (United States)

    Cheon, Yoon-Hee; Kim, Ju-Young; Baek, Jong Min; Ahn, Sung-Jun; Jun, Hong Young; Erkhembaatar, Munkhsoyol; Kim, Min Seuk; Lee, Myeung Su; Oh, Jaemin

    2016-02-01

    levels of genes related to osteoblast differentiation, and induced the phosphorylation of Akt, p38, and Smad1/5/8. Furthermore, 5-week-old ICR mice treated with WHI-131 exhibited antiresorbing effects in a lipopolysaccharide-induced calvaria bone loss model in vivo and increased bone-forming activity in a calvarial bone formation model. Therefore, the results of this study show that WHI-131 plays a dual role by inhibiting osteoclast differentiation and promoting osteoblast differentiation. Thus, WHI-131 could be a useful pharmacological agent to treat osteoporosis by promoting bone growth and inhibiting resorption.

  4. Osteobiology: newest bone organ topics and the platelet-rich plasma treatment.

    Directory of Open Access Journals (Sweden)

    Ananias García Cardona

    2007-11-01

    Full Text Available The bone is a dynamic tissue taht provides mechanical support, physical protection, storage site for minerals, and enables genesis movement. The bone biology (osteobiology is regulated by the balance betqeen osteoblastic formation and osteoclatic resorption. the skeletal bone homeostasis is influenced by components of the bone marrow organ, neuroendocrine system and hemato-inmmune system. The purpose of this review is to describe the biodynamic of the bone organ, and actual terapeutics with platelet-rich plasma in guide bone regeneration, a co-surgical method employed to increase the quantity and quality of the bone.

  5. RECENT ADVANCES IN PATHO-BIOLOGY OF MYELOMA BONE DISEASE: CLINICOPATHOLOGY AND LITERATURE OF REVIEW

    Directory of Open Access Journals (Sweden)

    Lohit Kumar

    2016-03-01

    Full Text Available Bone disease is a hallmark of multiple myeloma, presenting as lytic lesions associated with bone pain, pathological fractures requiring surgery and/or radiation to bone, spinal cord compression and hypercalcaemia. Increased osteoclastic activity unaccompanied by a compensatory increase in osteoblast function, leading to enhanced bone resorption results in bone disease. The interaction of plasma cells with the bone marrow microenvironment has been shown to play a vital role. Also, interactions of myeloma cells with osteoclasts enhance myeloma growth and survival, and thereby create a vicious cycle leading to extensive bone destruction and myeloma cell expansion.

  6. 骨生化指标在骨肿瘤中的临床应用进展%Clinical application progress of bone biochemical markers in bone tumors

    Institute of Scientific and Technical Information of China (English)

    周定; 张琪琪; 胡勇

    2014-01-01

    Bone tumors refer to benign and malignant tumors which originate from mesenchymal stem cells and occur in bone tissues and their accessory structures. The pathogenesis and etiology of bone tumors still remain unclear, and the diagnosis methods of bone tumors are stagnating now. X-ray, computed tomography ( CT ) and magnetic resonance imaging ( MRI ) are important in diagnosing and evaluating bone tumors, but they cannot detect the lesions until the bone destruction reaches a certain degree. Isotope bone scan can detect the microscopic lesions of bone, whereas it is too expensive and the speciifcity is poor, with high false positive rates. At present, the golden standard for the diagnosis of bone tumors is the histopathological examination of bone. However, it is dififcult to achieve early diagnosis, and it is likely to miss the best treatment period. Every disease is inevitably accompanied by molecular biological changes in the body. Biochemical markers can promptly detect the property changes of bone tumor cells, including unlimited proliferation, apoptosis, active neoangiogenesis, inifltrative growth, metastatic growth and so on. Therefore, it is of great signiifcance for the diagnosis of bone tumors to detect appropriate biochemical markers in the patients. The normal bone metabolism is maintained by the dynamic balance of bone resorption and bone formation. When bone tumors occur, the balance will be disturbed. The bone biochemical markers which relfect bone resorption and bone formation are sensitive indicators of early abnormal bone metabolism. Recently, a large number of studies have explored the significance of bone biochemical markers in patients with bone tumors. The functions of bone biochemical markers in patients with bone tumors mainly include making an early detection of microscopic tumor lesions to start early treatment ( diagnostic effects ), evaluating the effects ( therapeutic monitoring ), evaluating the prognosis and predicting the risk of

  7. Computer-simulated bone architecture in a simple bone-remodeling model based on a reaction-diffusion system.

    Science.gov (United States)

    Tezuka, Ken-ichi; Wada, Yoshitaka; Takahashi, Akiyuki; Kikuchi, Masanori

    2005-01-01

    Bone is a complex system with functions including those of adaptation and repair. To understand how bone cells can create a structure adapted to the mechanical environment, we propose a simple bone remodeling model based on a reaction-diffusion system influenced by mechanical stress. Two-dimensional bone models were created and subjected to mechanical loads. The conventional finite element method (FEM) was used to calculate stress distribution. A stress-reactive reaction-diffusion model was constructed and used to simulate bone remodeling under mechanical loads. When an external mechanical stress was applied, stimulated bone formation and subsequent activation of bone resorption produced an efficient adaptation of the internal shape of the model bone to a given stress, and demonstrated major structures of trabecular bone seen in the human femoral neck. The degree of adaptation could be controlled by modulating the diffusion constants of hypothetical local factors. We also tried to demonstrate the deformation of bone structure during osteoporosis by the modulation of a parameter affecting the balance between formation and resorption. This simple model gives us an insight into how bone cells can create an architecture adapted to environmental stress, and will serve as a useful tool to understand both physiological and pathological states of bone based on structural information.

  8. Bone metabolism and renal stone risk during International Space Station missions.

    Science.gov (United States)

    Smith, Scott M; Heer, Martina; Shackelford, Linda C; Sibonga, Jean D; Spatz, Jordan; Pietrzyk, Robert A; Hudson, Edgar K; Zwart, Sara R

    2015-12-01

    Bone loss and renal stone risk are longstanding concerns for astronauts. Bone resorption brought on by spaceflight elevates urinary calcium and the risk of renal stone formation. Loss of bone calcium leads to concerns about fracture risk and increased long-term risk of osteoporosis. Bone metabolism involves many factors and is interconnected with muscle metabolism and diet. We report here bone biochemistry and renal stone risk data from astronauts on 4- to 6-month International Space Station missions. All had access to a type of resistive exercise countermeasure hardware, either the Advanced Resistance Exercise Device (ARED) or the Interim Resistance Exercise Device (iRED). A subset of the ARED group also tested the bisphosphonate alendronate as a potential anti-resorptive countermeasure (Bis+ARED). While some of the basic bone marker data have been published, we provide here a more comprehensive evaluation of bone biochemistry with a larger group of astronauts. Regardless of exercise, the risk of renal stone formation increased during spaceflight. A key factor in this increase was urine volume, which was lower during flight in all groups at all time points. Thus, the easiest way to mitigate renal stone risk is to increase fluid consumption. ARED use increased bone formation without changing bone resorption, and mitigated a drop in parathyroid hormone in iRED astronauts. Sclerostin, an osteocyte-derived negative regulator of bone formation, increased 10-15% in both groups of astronauts who used the ARED (p<0.06). IGF-1, which regulates bone growth and formation, increased during flight in all 3 groups (p<0.001). Our results are consistent with the growing body of literature showing that the hyper-resorptive state of bone that is brought on by spaceflight can be countered pharmacologically or mitigated through an exercise-induced increase in bone formation, with nutritional support. Key questions remain about the effect of exercise-induced alterations in bone

  9. Mechanisms for the bone anabolic effect of parathyroid hormone treatment in humans

    DEFF Research Database (Denmark)

    Aslan, Derya; Dahl Andersen, Mille; Gede, Lene Bjerring;

    2012-01-01

    Intermittent low-dose treatment with parathyroid hormone (PTH) analogues has become widely used in the treatment of severe osteoporosis. During normal physiological conditions, PTH stimulates both bone formation and resorption, and in patients with primary hyperparathyroidism, bone loss is frequent...

  10. Dissolution of the inorganic phase of bone leading to release of calcium regulates osteoclast survival

    DEFF Research Database (Denmark)

    Nielsen, Rasmus H; Karsdal, Morten A; Sørensen, Mette G;

    2007-01-01

    Osteoclasts are the sole cells possessing the ability to resorb calcified bone matrix. This occurs via secretion of hydrochloric acid mediated by the V-ATPase and the chloride channel ClC-7. Loss of acidification leads to osteopetrosis characterized by ablation of bone resorption and increased os...

  11. The Role of Osteoblast-Derived Inflammatory Cytokines in Bone Metastatic Breast Cancer

    Science.gov (United States)

    2008-03-01

    examination, approximately 70% of patients who die from breast or prostate cancer have bone metastases [1]. The incidences from thyroid, kidney , and lung...The adipocyte has been found to secrete tumor necrosis factor- alpha (TNF-α), IL-6, and leptin , which stimulate bone resorption and inhibit

  12. Osteocyte-viability-based simulations of trabecular bone loss and recovery in disuse and reloading

    NARCIS (Netherlands)

    Wang, H.; Ji, B.; Liu, X.S.; van Oers, R.F.M.; Guo, X.E.; Huang, Y.; Hwang, K.C.

    2014-01-01

    Osteocyte apoptosis is known to trigger targeted bone resorption. In the present study, we developed an osteocyte-viability-based trabecular bone remodeling (OVBR) model. This novel remodeling model, combined with recent advanced simulation methods and analysis techniques, such as the element-by-ele

  13. Improvement of Lumbar Bone Mass after Infliximab Therapy in Crohn’s Disease Patients

    Directory of Open Access Journals (Sweden)

    Marina Mauro

    2007-01-01

    Full Text Available BACKGROUND: Patients with Crohn’s disease (CD have a high risk of developing osteoporosis, but the mechanisms underlying bone mass loss are unclear. Elevated proinflammatory cytokines, such as tumour necrosis factor-alpha (TNFα, have been implicated in the pathogenesis of bone resorption.

  14. Bone replacement following dental trauma prior to implant surgery - present status

    NARCIS (Netherlands)

    Hallman, Mats; Mordenfeld, Arne; Strandkvist, Tomas

    2009-01-01

    Dento-alveolar trauma often leads to a need for reconstruction of the alveolar crest before an implant can be placed. Although autogenous bone grafts is considered the 'gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has i

  15. Expression of RANKL/OPG during bone remodeling in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H., E-mail: tnk@ymghp.jp [Department of Orthopedic Surgery, Yamaguchi Grand Medical Center, 77 Ohsaki, Hofu, Yamaguchi 747-8511 (Japan); Gerontology Research Center, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224 (United States); Mine, T. [Department of Orthopedic Surgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Ogasa, H. [Gerontology Research Center, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224 (United States); Department of Orthopedic Surgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Taguchi, T. [Department of Orthopedic Surgery, Yamaguchi University School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Liang, C.T. [Gerontology Research Center, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224 (United States); National Health Research Institutes, Taipei 115, Taiwan (China)

    2011-08-12

    Highlights: {yields} This is the first study to determine the relationship between osteogenic differentiation and RANKL/OPG expression during bone remodeling in vivo. {yields} The OPG expression peak occurred during the bone formation phase, whereas the marked elevation of RANKL expression was observed during the bone resorption phase. {yields} Histological analysis showed that RANKL/OPG immunoreactivity was predominantly associated with bone marrow cells in the marrow cavity. {yields} The present study confirmed that RANKL/OPG are key factors linking bone formation to resorption during the bone remodeling process. -- Abstract: The interaction between receptor activator of nuclear factor {kappa}B ligand (RANKL) and osteoprotegerin (OPG) plays a dominant role in osteoclastogenesis. As both proteins are produced by osteoblast lineage cells, they are considered to represent a key link between bone formation and resorption. In this study, we investigated the expression of RANKL and OPG during bone remodeling in vivo to determine the relationship between osteoclastogenic stimulation and osteoblastic differentiation. Total RNA was prepared from rat femurs after marrow ablation on days 0, 3, 6, and 9. The temporal activation patterns of osteoblast-related genes (procollagen {alpha}1 (I), alkaline phosphatase, osteopontin, and osteocalcin) were examined by Northern blot analysis. An appreciable increase in the expression of these osteoblast markers was observed on day 3. The peak increase in gene expression was observed on day 6 followed by a slight reduction by day 9. Real-time PCR analysis showed that the OPG mRNA expression was markedly upregulated on day 6 and slightly decreased on day 9. In contrast, RANKL mRNA expression was increased by more than 20-fold on day 9. The RANKL/OPG ratio, an index of osteoclastogenic stimulation, peaked on day 9. Histological analysis showed that RANKL and OPG immunoreactivity were predominantly associated with bone marrow cells. The

  16. Human stem cell osteoblastogenesis mediated by novel glycogen synthase kinase 3 inhibitors induces bone formation and a unique bone turnover biomarker profile in rats

    Energy Technology Data Exchange (ETDEWEB)

    Gilmour, Peter S., E-mail: Peter.Gilmour@astrazeneca.com [New Opportunities Innovative Medicines group, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); O' Shea, Patrick J.; Fagura, Malbinder [New Opportunities Innovative Medicines group, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); Pilling, James E. [Discovery Sciences, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); Sanganee, Hitesh [New Opportunities Innovative Medicines group, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); Wada, Hiroki [R and I IMed, AstraZeneca R and D, Molndal (Sweden); Courtney, Paul F. [DMPK, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); Kavanagh, Stefan; Hall, Peter A. [Safety Assessment, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom); Escott, K. Jane [New Opportunities Innovative Medicines group, AstraZeneca R and D, Alderley Park, Cheshire SK10 4TF (United Kingdom)

    2013-10-15

    Wnt activation by inhibiting glycogen synthase kinase 3 (GSK-3) causes bone anabolism in rodents making GSK-3 a potential therapeutic target for osteoporotic and osteolytic metastatic bone disease. To understand the wnt pathway related to human disease translation, the ability of 3 potent inhibitors of GSK-3 (AZD2858, AR79, AZ13282107) to 1) drive osteoblast differentiation and mineralisation using human adipose-derived stem cells (hADSC) in vitro; and 2) stimulate rat bone formation in vivo was investigated. Bone anabolism/resorption was determined using clinically relevant serum biomarkers as indicators of bone turnover and bone formation assessed in femurs by histopathology and pQCT/μCT imaging. GSK-3 inhibitors caused β-catenin stabilisation in human and rat mesenchymal stem cells, stimulated hADSC commitment towards osteoblasts and osteogenic mineralisation in vitro. AZD2858 produced time-dependent changes in serum bone turnover biomarkers and increased bone mass over 28 days exposure in rats. After 7 days, AZD2858, AR79 or AZ13282107 exposure increased the bone formation biomarker P1NP, and reduced the resorption biomarker TRAcP-5b, indicating increased bone anabolism and reduced resorption in rats. This biomarker profile was differentiated from anabolic agent PTH{sub 1–34} or the anti-resorptive Alendronate-induced changes. Increased bone formation in cortical and cancellous bone as assessed by femur histopathology supported biomarker changes. 14 day AR79 treatment increased bone mineral density and trabecular thickness, and decreased trabecular number and connectivity assessed by pQCT/μCT. GSK-3 inhibition caused hADSC osteoblastogenesis and mineralisation in vitro. Increased femur bone mass associated with changes in bone turnover biomarkers confirmed in vivo bone formation and indicated uncoupling of bone formation and resorption. - Highlights: • Wnt modulation with 3 novel GSK-3 inhibitors alters bone growth. • Human stem cell osteoblastogenesis

  17. Impact and risk factors of post-stroke bone fracture.

    Science.gov (United States)

    Huo, Kang; Hashim, Syed I; Yong, Kimberley L Y; Su, Hua; Qu, Qiu-Min

    2016-02-20

    Bone fracture occurs in stroke patients at different times during the recovery phase, prolonging recovery time and increasing medical costs. In this review, we discuss the potential risk factors for post-stroke bone fracture and preventive methods. Most post-stroke bone fractures occur in the lower extremities, indicating fragile bones are a risk factor. Motor changes, including posture, mobility, and balance post-stroke contribute to bone loss and thus increase risk of bone fracture. Bone mineral density is a useful indicator for bone resorption, useful to identify patients at risk of post-stroke bone fracture. Calcium supplementation was previously regarded as a useful treatment during physical rehabilitation. However, recent data suggests calcium supplementation has a negative impact on atherosclerotic conditions. Vitamin D intake may prevent osteoporosis and fractures in patients with stroke. Although drugs such as teriparatide show some benefits in preventing osteoporosis, additional clinical trials are needed to determine the most effective conditions for post-stroke applications.

  18. Microelements for bone boost: the last but not the least

    Science.gov (United States)

    Pepa, Giuseppe Della; Brandi, Maria Luisa

    2016-01-01

    Summary Osteoporosis is a major public health problem affects many millions of people around the world. It is a metabolic bone disease characterized by loss of bone mass and strength, resulting in increased risk of fractures. Several lifestyle factors are considered to be important determinants of it and nutrition can potentially have a positive impact on bone health, in the development and maintenance of bone mass and in the prevention of osteoporosis. There are potentially numerous nutrients and dietary components that can influence bone health, and these range from the macronutrients to micronutrients. In the last decade, epidemiological studies and clinical trials showed micronutrients can potentially have a positive impact on bone health, preventing bone loss and fractures, decreasing bone resorption and increasing bone formation. Consequently, optimizing micronutrients intake might represent an effective and low-cost preventive measure against osteoporosis. PMID:28228778

  19. Effect of epimedium pubescen flavonoid on bone mineral status and bone turnover in male rats chronically exposed to cigarette smoke

    Directory of Open Access Journals (Sweden)

    Gao Shu-guang

    2012-06-01

    Full Text Available Abstract Background Epimedii herba is one of the most frequently used herbs in formulas that are prescribed for the treatment of osteoporosis in China and its main constituent is Epimedium pubescen flavonoid (EPF. However, it is unclear whether EPF during chronic exposure to cigarette smoke may have a protective influence on the skeleton. The present study investigated the effect of EPF on bone mineral status and bone turnover in a rat model of human relatively high exposure to cigarette smoke. Methods Fifty male Wistar rats were randomized into five groups: controls, passive smoking groups and passive smoking rats administered EPF at three dosage levels (75, 150 or 300 mg/kg/day in drinking water for 4 months. A rat model of passive smoking was prepared by breeding male rats in a cigarette-smoking box. Bone mineral content (BMC, bone mineral density (BMD, bone turnover markers, bone histomorphometric parameters and biomechanical properties were examined. Results Smoke exposure decreased BMC and BMD, increased bone turnover (inhibited bone formation and stimulated its resorption, affected bone histomorphometry (increased trabecular separation and osteoclast surface per bone surface; decreased trabecular bone volume, trabecular thickness, trabecular number, cortical thickness, bone formation rate and osteoblast surface per bone surface, and reduced mechanical properties. EPF supplementation during cigarette smoke exposure prevented smoke-induced changes in bone mineral status and bone turnover. Conclusion The results suggest that EPF can prevent the adverse effects of smoke exposure on bone by stimulating bone formation and inhibiting bone turnover and bone resorption.

  20. The correlation between postmenopausal osteoporosis and inflammatory periodontitis regarding bone loss in experimental models.

    Science.gov (United States)

    Kobayashi, Megumi; Matsumoto, Chiho; Hirata, Michiko; Tominari, Tsukasa; Inada, Masaki; Miyaura, Chisato

    2012-01-01

    We have invented a mouse model of periodontitis associated with alveolar bone loss induced by lipopolysaccharide. Ovariectomized (OVX) animals are widely used as a model for osteoporosis due to estrogen deficiency. To define the relationship between periodontitis and osteoporosis, we examined the influence of estrogen deficiency on the mouse alveolar bone mass. In OVX mice, bone loss was detected not only in the femur, but also in the alveolar bone, indicating that estrogen deficiency could induce resorption in alveolar bone. In experiments using a combination of osteoporosis and periodontitis models, OVX significantly enhanced the alveolar bone loss in the model of periodontitis. Therefore, postmenopausal osteoporosis may enhance the risk of periodontitis associated with inflammatory alveolar bone resorption.

  1. Clinical indications for digital imaging in dento-alveolar trauma. Part 2: root resorption.

    Science.gov (United States)

    Cohenca, Nestor; Simon, James H; Mathur, Aeshna; Malfaz, Jose Maria

    2007-04-01

    Common complications of dento-alveolar trauma are pulp necrosis, pulp canal obliteration, periapical pathosis and root resorption. Different types of root resorption have been identified with traumatic injuries. Repair-related (surface), infection-related (inflammatory), ankylosis-related (osseous replacement) or extraradicular invasive cervical resorption are among the most common. Recent developments in imaging systems have enabled clinicians to visualize structural changes effectively. The diagnosis and three-dimensional imaging assessment of the resorption is important in order to determine the treatment complexity and expected outcome based on the location and extension of the root defect. This article discusses and illustrates the clinical application of cone beam computed tomography for diagnosis and treatment plan of root resorption. Four clinical cases are presented to illustrate the potential use of the NewTom 3G for root resorption.

  2. Orthodontic treatment in patient with idiopathic root resorption: A case report

    Directory of Open Access Journals (Sweden)

    Diego Rey

    2015-02-01

    Full Text Available Multiple idiopathic external root resorption is a rare pathological condition usually detected as an incidental radiographic finding. External root resorption of permanent teeth is a multifactorial process related to several local and systemic factors. If an etiological factor cannot be identified for root resorption, the term "idiopathic" is applied. This report presents a case of multiple idiopathic apical root resorption. The condition was found in a young female patient seeking orthodontic treatment due to malocclusion. This kind of resorption starts apically and progresses coronally, causing a gradual shortening and rounding of the remaining root. Patients with this condition are not the ideal candidates for orthodontic treatment; however, the aim of this report is to describe an unusual case of idiopathic root resorption involving the entire dentition, and to present the orthodontic treatment of this patient. It describes the progress and completion of orthodontic therapy with satisfactory end results.

  3. Nonsurgical Endodontic Retreatment of Advanced Inflammatory External Root Resorption Using Mineral Trioxide Aggregate Obturation

    OpenAIRE

    2012-01-01

    Inflammatory external root resorption is one of the major complications after traumatic dental injury. In this case report, we describe treatment of a maxillary central incisor affected by severe, perforating external root resorption. An 18-year-old patient presented with a previously traumatized, root-filled maxillary central incisor associated with pain and sinus tract. Radiographic examination revealed periradicular lesion involving pathologic resorption of the apical region of the root an...

  4. Using waste heat for cooling with compact resorption plants; Kompakte Resorptionsanlagen zum Kuehlen mit Abwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, Thomas [Makatec GmbH, Bondorf (Germany); Helle, Kirsten [Institut fuer Energie- und Umwelttechnik (IUTA) e.V. Energy Conversion and Energy Storage, Duisburg (Germany)

    2012-03-15

    Cooling technologies gain an increasing importance in the industrialized world. Ammonia based absorption chillers can be employed for air conditioning and refrigeration, using waste heat as driving force. With using the resorption technology for ammonia based absorption chillers gas cleaning is needless. Resorption systems consist of two solvent cycles exchanging refrigerant, both with absorber, desorber and solvent heat exchanger. Plate heat exchangers or new membrane contactors used as desorber and absorber lead to compact resorption chillers. (orig.)

  5. Case report - Root resorption and ankylosis associated with guided tissue regeneration

    OpenAIRE

    Cury, PR; Furuse, C; Martins, MT; Sallum, EA; de Araujo, NS

    2005-01-01

    Background. Root resorption and ankylosis have been reported rarely as sequelae to guided tissue regeneration (GTR). The authors describe a clinical case of root resorption following GTR that involved the use of a bioabsorbable membrane. Case Description. Two years after GTR was performed on a Class II furcation defect, the clinical examination revealed root resorption reaching the pulp chamber. The furcation defect was filled with epithelium and connective tissue, which contained inflammator...

  6. TGF-β and Physiological Root Resorption of Deciduous Teeth

    Science.gov (United States)

    Shimazaki, Emi; Karakida, Takeo; Yamamoto, Ryuji; Kobayashi, Saeko; Fukae, Makoto; Yamakoshi, Yasuo; Asada, Yoshinobu

    2016-01-01

    The present study was performed to examine how transforming growth factor β (TGF-β) in root-surrounding tissues on deciduous teeth regulates the differentiation induction into odontoclasts during physiological root resorption. We prepared root-surrounding tissues with (R) or without (N) physiological root resorption scraped off at three regions (R1–R3 or N1–N3) from the cervical area to the apical area of the tooth and measured both TGF-β and the tartrate-resistant acid phosphatase (TRAP) activities. The TGF-β activity level was increased in N1–N3, whereas the TRAP activity was increased in R2 and R3. In vitro experiments for the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-mediated osteoclast differentiation revealed that proteins from N1–N3 and R1–R3 enhanced the TRAP activity in RAW264 cells. A genetic study indicated that the mRNA levels of TGF-β1 in N1 and N2 were significantly increased, and corresponded with levels of osteoprotegerin (OPG). In contrast, the expression level of RANKL was increased in R2 and R3. Our findings suggest that TGF-β is closely related to the regulation of OPG induction and RANKL-mediated odontoclast differentiation depending on the timing of RANKL and OPG mRNA expression in the root-surrounding tissues of deciduous teeth during physiological root resorption. PMID:28035998

  7. Disruption of bone and skeletal muscle in severe burns

    Institute of Scientific and Technical Information of China (English)

    Gordon L Klein

    2015-01-01

    Severe burn injury triggers the body’s nonspecific adaptive responses to acute insult, including the systemic inflammatory and stress responses, as well as the sympathetic response to immobilization. These responses trigger inflammatory bone resorption followed by glucocorticoid-induced apoptosis of osteoblasts and probably osteocytes. Because these patients are catabolic, they suffer concomitant muscle wasting and negative nitrogen balance. The use of anabolic agents such as recombinant human growth hormone and oxandrolone results in improved bone mineral content and muscle strength after approximately 1 year. Use of bisphosphonates within the first 10 days of a severe burn completely blocks the resorptive bone loss and has the added advantage of appearing to preserve muscle protein from excessive breakdown. The mechanism for the protective effect on muscle is not currently known. However, if the effect of bisphosphonates on muscle can be confirmed, it raises the possibility that bone communicates with muscle.

  8. Biogeographic patterns of nutrient resorption from Quercus variabilis Blume leaves across China.

    Science.gov (United States)

    Sun, X; Kang, H; Chen, H Y H; Björn, B; Samuel, B F; Liu, C

    2016-05-01

    The variation in nutrient resorption has been studied at different taxonomic levels and geographic ranges. However, the variable traits of nutrient resorption at the individual species level across its distribution are poorly understood. We examined the variability and environmental controls of leaf nutrient resorption of Quercus variabilis, a widely distributed species of important ecological and economic value in China. The mean resorption efficiency was highest for phosphorus (P), followed by potassium (K), nitrogen (N), sulphur (S), magnesium (Mg) and carbon (C). Resorption efficiencies and proficiencies were strongly affected by climate and respective nutrients concentrations in soils and green leaves, but had little association with leaf mass per area. Climate factors, especially growing season length, were dominant drivers of nutrient resorption efficiencies, except for C, which was strongly related to green leaf C status. In contrast, green leaf nutritional status was the primary controlling factor of leaf nutrient proficiencies, except for C. Resorption efficiencies of N, P, K and S increased significantly with latitude, and were negatively related to growing season length and mean annual temperature. In turn, N, P, K and S in senesced leaves decreased with latitude, likely due to their efficient resorption response to variation in climate, but increased for Mg and did not change for C. Our results indicate that the nutrient resorption efficiency and proficiency of Q. variabilis differed strongly among nutrients, as well as growing environments. Our findings provide important insights into understanding the nutrient conservation strategy at the individual species level and its possible influence on nutrient cycling.

  9. Orthodontic and nonorthodontic root resorption: their impact on clinical dental practice.

    Science.gov (United States)

    Kokich, Vincent G

    2008-08-01

    Occasionally, general dentists are challenged with providing restorative treatment for a postorthodontic patient who has had moderate to severe root resorption. When this happens, a number of questions about the cause of such resorption and the appropriate treatment arise in the dentist's mind. This article will describe the orthodontic and restorative management of three patients with severe maxillary incisor root resorption, provide a thorough discussion of the currently available literature on the topic of root resorption, and answer clinical questions regarding this relatively infrequent but devastating sequel to orthodontic treatment.

  10. Management of external perforating root resorption by intentional replantation followed by Biodentine restoration.

    Science.gov (United States)

    Pruthi, Preeti Jain; Dharmani, Umesh; Roongta, Ruchika; Talwar, Sangeeta

    2015-01-01

    Resorption of tooth structures can occur as a result of physiological, pathological, and idiopathic factors. Early diagnosis and appropriate treatment can prevent its serious complications. This case report presents surgical endodontic management of a trauma-induced perforating external root resorption, which was diagnosed with the help of cone beam computed tomography. Following root canal treatment, intentional replantation of the tooth was performed so as to expose the opening of the resorption defect to allow for complete debridement and closure. Eighteen months follow-up showed arrest of root resorption, and progressive healing of the defect.

  11. Primary tooth radicular resorption as a consequence of self-corrected ectopic eruption: 2 unusual cases.

    Science.gov (United States)

    Guzeler, Irem; Sara, Sezgi; Cehreli, Zafer C; Uysal, Serdar; Musselman, Robert J

    2011-01-01

    Resorption of the distal root of primary second molars is a common consequence of ectopically erupting permanent first molars. Here, we report 2 unusual cases of primary molar root resorption caused by reversible (self-correcting) ectopic eruption of premolar and canine teeth. In both cases, severe pathological resorption of the mesial roots of primary molars was detected on routine dental radiographs, and the affected molars remained asymptomatic until exfoliation. The purpose of this paper was, using 2 case studies, to highlight the possibility of primary root resorption as a sequel of self-corrected ectopic eruption in locations not frequently diagnosed or reported.

  12. Physiological and pathological factors and mechanisms in the process of root resorption in primary teeth

    Directory of Open Access Journals (Sweden)

    Bianca Zimmermann Santos

    2010-07-01

    Full Text Available Introduction: Tooth resorption is essential in the process of root resorption in primary teeth. However, pathological root resorption, mainly the inflammatory one, is a consequence and/or complication of several clinical conditions, such as dental trauma and periapical inflammatory lesions from dental caries, thus becoming a common cause of tooth loss. Objective: To present and discuss a literature review regarding the mechanisms of physiological and inflammatory pathological root resorption in primary teeth, emphasizing their biochemical and cellular events. Literature review: The odontoclasts cells are responsible for resorption of dental tissues, and they are influenced by several stimuli and molecular signals derived from cytokines, neuropeptides, hormones and degradation products released when tissue is injured. However, so far it is not clear what leads to the differentiation of the precursor cells of odontoclasts, what gives them the signal to start the resorption in a specific place and time (especially in primary teeth and why they are activated in some pathological conditions,but not in others.Conclusion: The knowledge regarding molecular mechanisms and factors that regulate the process of root resorption is still meager.Research in this area is of great relevance,since new knowledge about the molecular pathway(s involved in root resorption may allow the development of different therapies, more biological ones, in order to control or prevent resorption, thus preventing tooth loss and its consequences.

  13. Identification of factors associated with pathological root resorption in traumatized primary teeth.

    Science.gov (United States)

    Cardoso, Mariane; Rocha, Maria José de Carvalho

    2008-06-01

    The aim of this study was to determine the factors associated with the development of pathological root resorptions in traumatized primary teeth. Based on Dental Reports on Traumatism from the Assistance Program for the Traumatized Patient, 90 children were selected. Among these children, 45 did not present pathological root resorption, while 45 did (23 replacement root resorptions and 22 external inflammatory root resorptions). Possible factors associated with the development of the pathological resorption include: (i) over 18 months or over 52 months of age, (ii) complicated trauma, and (iii) presence of more than one trauma in the same tooth. Using the chi-squared test, it was verified that trauma recurrence was considered to be a factor associated with the development of pathological root resorption (chi(2) = 3.636; P children with trauma recurrence present a 2.6 times higher chance of developing pathological root resorptions when compared with children that did not report trauma recurrence. Through the univaried logistic regression test, it was also observed that the association of two or three factors caused the chances of pathological root resorption development to increase by 3.8 times in 18-month-old children or older (95% CI: 1.5-9.7) and by 5.1 times in 52-month-old children or older (95% CI: 1.5-17). Trauma recurrence in the same primary tooth is associated with pathological root resorption, and the interaction among two or three factors increases the chance of developing such sequelae.

  14. Bone Biopsy

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Biopsy Bone biopsy uses a needle and imaging ... the limitations of Bone Biopsy? What is a Bone Biopsy? A bone biopsy is an image-guided ...

  15. Short Anabolic Peptides for Bone Growth.

    Science.gov (United States)

    Amso, Zaid; Cornish, Jillian; Brimble, Margaret A

    2016-07-01

    Loss of bone occurs in the age-related skeletal disorder, osteoporosis, leading to bone fragility and increased incidence of fractures, which are associated with enormous costs and substantial morbidity and mortality. Recent data indicate that osteoporotic fractures are more common than other diseases, which usually attract public attention (e.g., heart attack and breast cancer). The prevention and treatment of this skeletal disorder are therefore of paramount importance. Majority of osteoporosis medications restore skeletal balance by reducing osteoclastic activity, thereby reducing bone resorption. These agents, however, do not regenerate damaged bone tissue, leaving limited options for patients once bone loss has occurred. Recently, attention has turned to bone-anabolic agents. Such agents have the ability to increase bone mass and strength, potentially reversing structural damage. To date, only one bone-anabolic drug is available in the market. The discovery of more novel, cost-effective bone anabolic agents is therefore a priority to treat those suffering from this disabling condition. Short peptides offer an important alternative for the development of novel bone-anabolic agents given their high target binding specificity, which translates into potent activity with limited side effects. This review summarizes attempts in the identification of bone-anabolic peptides, and their development for promoting bone growth.

  16. Artificial Gravity: Effects on Bone Turnover

    Science.gov (United States)

    Heer, M.; Zwart, S /R.; Baecker, N.; Smith, S. M.

    2007-01-01

    The impact of microgravity on the human body is a significant concern for space travelers. Since mechanical loading is a main reason for bone loss, artificial gravity might be an effective countermeasure to the effects of microgravity. In a 21-day 6 head-down tilt bed rest (HDBR) pilot study carried out by NASA, USA, the utility of artificial gravity (AG) as a countermeasure to immobilization-induced bone loss was tested. Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density was determined by DXA and pQCT before and after bed rest. Urinary excretion of bone resorption markers (n-telopeptide and helical peptide) were increased from pre-bed rest, but there was no difference between the control and the AG group. The same was true for serum c-telopeptide measurements. Bone formation markers were affected by bed rest and artificial gravity. While bone-specific alkaline phosphatase tended to be lower in the AG group during bed rest (p = 0.08), PINP, another bone formation marker, was significantly lower in AG subjects than CN before and during bed rest. PINP was lower during bed rest in both groups. For comparison, artificial gravity combined with ergometric exercise was tested in a 14-day HDBR study carried out in Japan (Iwase et al. J Grav Physiol 2004). In that study, an exercise regime combined with AG was able to significantly mitigate the bed rest-induced increase in the bone resorption marker deoxypyridinoline. While further study is required to more clearly differentiate bone and muscle effects, these initial data demonstrate the potential effectiveness of short-radius, intermittent AG as a countermeasure to the bone deconditioning that occurs during bed rest and spaceflight. Future studies will need to optimize not only the AG prescription (intensity and duration), but will likely need to include the use of exercise or other combined treatments.

  17. Progesterone and Bone: Actions Promoting Bone Health in Women

    Directory of Open Access Journals (Sweden)

    Vanadin Seifert-Klauss

    2010-01-01

    Full Text Available Estradiol (E2 and progesterone (P4 collaborate within bone remodelling on resorption (E2 and formation (P4. We integrate evidence that P4 may prevent and, with antiresorptives, treat women's osteoporosis. P4 stimulates osteoblast differentiation in vitro. Menarche (E2 and onset of ovulation (P4 both contribute to peak BMD. Meta-analysis of 5 studies confirms that regularly cycling premenopausal women lose bone mineral density (BMD related to subclinical ovulatory disturbances (SODs. Cyclic progestin prevents bone loss in healthy premenopausal women with amenorrhea or SOD. BMD loss is more rapid in perimenopause than postmenopause—decreased bone formation due to P4 deficiency contributes. In 4 placebo-controlled RCTs, BMD loss is not prevented by P4 in postmenopausal women with increased bone turnover. However, 5 studies of E2-MPA co-therapy show greater BMD increases versus E2 alone. P4 fracture data are lacking. P4 prevents bone loss in pre- and possibly perimenopausal women; progesterone co-therapy with antiresorptives may increase bone formation and BMD.

  18. Histologic diagnosis of metabolic bone diseases: bone histomorphometry

    Directory of Open Access Journals (Sweden)

    L. Dalle Carbonare

    2011-09-01

    Full Text Available Histomorphometry or quantitative histology is the analysis on histologic sections of bone resorption parameters, formation and structure. It is the only technique that allows a dynamic evaluation of the activity of bone modelling after labelling with tetracycline. Moreover, the new measurement procedures through the use of the computer allow an assessment of bone microarchitecture too. Histomorphometric bone biopsy is a reliable and well-tolerated procedure. Complications are reported only in 1% of the subjects (hematoma, pain, transient neuralgia. Histomorphometry is used to exclude or confirm the diagnosis of osteomalacia. It is employed in the evaluation of bone damage associated with particular treatments (for example, anticonvulsants or in case of rare bone diseases (osteogenesis imperfecta, systemic mastocytosis. It is also an essential approach when clinical, biochemical and other diagnostic data are not consistent. Finally, it is a useful method to understand the pathophysiologic mechanisms of drugs. The bone sample is taken at the level of iliac crest under local anesthesia. It is then put into methyl-metacrilate resin where the sections are prepared for the microscopic analysis of the various histomorphometric parameters.

  19. Influence of ingrowth regions on bone remodelling around a cementless hip resurfacing femoral implant.

    Science.gov (United States)

    Haider, Ifaz T; Speirs, Andrew D; Beaulé, Paul E; Frei, Hanspeter

    2015-01-01

    Hip resurfacing arthroplasty is an alternative to traditional hip replacement that can conserve proximal bone stock and has gained popularity but bone resorption may limit implant survival and remains a clinical concern. The goal of this study was to analyze bone remodelling patterns around an uncemented resurfacing implant and the influence of ingrowth regions on resorption. A computed tomography-derived finite element model of a proximal femur with a virtually implanted resurfacing component was simulated under peak walking loads. Bone ingrowth was simulated by six interface conditions: fully bonded; fully friction; bonded cap with friction stem; a small bonded region at the stem-cup intersection with the remaining surface friction; fully frictional, except for a bonded band along the distal end of the cap and superior half of the cap bonded with the rest frictional. Interface condition had a large influence on remodelling patterns. Bone resorption was minimized when no ingrowth occurred at the bone-implant interface. Bonding only the superior half of the cap increased bone resorption slightly but allowed for a large ingrowth region to improve secondary stability.

  20. Myricetin Prevents Alveolar Bone Loss in an Experimental Ovariectomized Mouse Model of Periodontitis

    Directory of Open Access Journals (Sweden)

    Jialiang Huang

    2016-03-01

    Full Text Available Periodontitis is a common chronic inflammatory disease, which leads to alveolar bone resorption. Healthy and functional alveolar bone, which can support the teeth and enable their movement, is very important for orthodontic treatment. Myricetin inhibited osteoclastogenesis by suppressing the expression of some genes, signaling pathways, and cytokines. This study aimed to investigate the effects of myricetin on alveolar bone loss in an ovariectomized (OVX mouse model of periodontitis as well as in vitro osteoclast formation and bone resorption. Twenty-four healthy eight-week-old C57BL/J6 female mice were assigned randomly to four groups: phosphate-buffered saline (PBS control (sham OVX + ligature + PBS (vehicle, and OVX + ligature + low or high (2 or 5 mg∙kg−1∙day−1, respectively doses of myricetin. Myricetin or PBS was injected intraperitoneally (i.p. every other day for 30 days. The maxillae were collected and subjected to further examination, including micro-computed tomography (micro-CT, hematoxylin and eosin (H&E staining, and tartrate-resistant acid phosphatase (TRAP staining; a resorption pit assay was also performed in vitro to evaluate the effects of myricetin on receptor activator of nuclear factor κ-B ligand (RANKL-induced osteoclastogenesis. Myricetin, at both high and low doses, prevented alveolar bone resorption and increased alveolar crest height in the mouse model and inhibited osteoclast formation and bone resorption in vitro. However, myricetin was more effective at high dose than at low dose. Our study demonstrated that myricetin had a positive effect on alveolar bone resorption in an OVX mouse model of periodontitis and, therefore, may be a potential agent for the treatment of periodontitis and osteoporosis.

  1. Myricetin Prevents Alveolar Bone Loss in an Experimental Ovariectomized Mouse Model of Periodontitis.

    Science.gov (United States)

    Huang, Jialiang; Wu, Chuanlong; Tian, Bo; Zhou, Xiao; Ma, Nian; Qian, Yufen

    2016-03-22

    Periodontitis is a common chronic inflammatory disease, which leads to alveolar bone resorption. Healthy and functional alveolar bone, which can support the teeth and enable their movement, is very important for orthodontic treatment. Myricetin inhibited osteoclastogenesis by suppressing the expression of some genes, signaling pathways, and cytokines. This study aimed to investigate the effects of myricetin on alveolar bone loss in an ovariectomized (OVX) mouse model of periodontitis as well as in vitro osteoclast formation and bone resorption. Twenty-four healthy eight-week-old C57BL/J6 female mice were assigned randomly to four groups: phosphate-buffered saline (PBS) control (sham) OVX + ligature + PBS (vehicle), and OVX + ligature + low or high (2 or 5 mg∙kg(-1)∙day(-1), respectively) doses of myricetin. Myricetin or PBS was injected intraperitoneally (i.p.) every other day for 30 days. The maxillae were collected and subjected to further examination, including micro-computed tomography (micro-CT), hematoxylin and eosin (H&E) staining, and tartrate-resistant acid phosphatase (TRAP) staining; a resorption pit assay was also performed in vitro to evaluate the effects of myricetin on receptor activator of nuclear factor κ-B ligand (RANKL)-induced osteoclastogenesis. Myricetin, at both high and low doses, prevented alveolar bone resorption and increased alveolar crest height in the mouse model and inhibited osteoclast formation and bone resorption in vitro. However, myricetin was more effective at high dose than at low dose. Our study demonstrated that myricetin had a positive effect on alveolar bone resorption in an OVX mouse model of periodontitis and, therefore, may be a potential agent for the treatment of periodontitis and osteoporosis.

  2. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Densitometry (DEXA) Bone densitometry, also called dual-energy ... limitations of DEXA Bone Densitometry? What is a Bone Density Scan (DEXA)? Bone density scanning, also called ...

  3. Equine Odontoclastic Tooth Resorption and Hypercementosis: Histopathologic Features.

    Science.gov (United States)

    Smedley, R C; Earley, E T; Galloway, S S; Baratt, R M; Rawlinson, J E

    2015-09-01

    Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a painful progressive condition of older horses that involves multiple teeth, including canines and incisors. EOTRH is uncommonly recognized by veterinary pathologists and in some cases may be misdiagnosed as cementoblastoma. The cause is unknown. The goals of this study were to describe the histopathologic features of EOTRH in 17 affected horses from the United States and to increase awareness of this condition. Samples ranged from affected tooth to the entire rostral mandible and maxilla. Affected teeth exhibited cemental hyperplasia and lysis. The marked proliferation of cementum in severe cases caused bulbous enlargement of the intra-alveolar portions of affected teeth. Several teeth contained necrotic debris, bacteria, and plant material in the regions of cemental lysis. All horses exhibited dentinal lysis in at least affected tooth, and several contained necrotic debris in these regions. Endodontic disease was often present with inflammation, lysis, necrotic debris, fibrosis, and/or a thin rim of atubular mineralized tissue in the pulp cavity. Periodontal disease was a common feature that was primarily characterized by moderate lymphoplasmacytic inflammation. Resorption with secondary hypercementosis appears to begin on the external surface of the teeth rather than within the pulp cavity. Distinguishing EOTRH from other diseases requires a complete history that includes the number and location of affected teeth, a gross description of regional hard/soft tissue health, and radiographic findings.

  4. Condylar Resorption After Orthognathic Surgery: A Systematic Review

    Science.gov (United States)

    de Moraes, Paulo Hemerson; Rizzati-Barbosa, Célia Marisa; Olate, Sergio; Moreira, Roger Willian Fernandes; de Moraes, Márcio

    2016-01-01

    Summary The aim of this research was to evaluate the risk factors related to condylar resorption (CR) after orthognathic surgery. Was realized a systematic review with a search of the literature performed in the electronic databases PubMed, MedLine, Ovid, Cochrane Library for current evidence in the world literature as conducted, and relevant articles were selected in according to inclusion and exclusion criteria and the findings were compared. Eight papers, (follow-up 12 months to 69 months) were including. A sample of 2567 patient with mandible or bi maxillary surgery with an age range from 14 to 46 year old was observed. In 137 patients (5.3%) CR was observed, with a 97.6% (122) female. CR was related to 118 cases with mandibular deficiencies with high mandibular plane (advancement surgery). CR were present principally in bi maxillary surgery with a 103 cases (75.2%) and only two papers show any analysis to the relation with TMJ dysfunction. Current evidence in CR is poor but supports those female patients with mandibular deficiency and high mandibular plane angle submitted to bi maxillary surgery with change in occlusal plane (counterclockwise) are associated with condylar resorption after orthognathic surgery. PMID:28066126

  5. [Effects of SERMs on bone health. Mechanisms of bone mass control by selective estrogen receptor modulator].

    Science.gov (United States)

    Imai, Yuuki; Kato, Shigeaki

    2010-03-01

    The bone mass, which is controlled by the balances between bone formation and bone resorption can be reduced by estrogen deficiency in post-menopausal osteoporosis. Reduced bone mass can be recovered by hormone replacement therapy (HRT) , however, HRT has various side effects. Although SERMs can rescue the bone mass with less side effect compared to HRT, the precise mechanisms of this effect is still elusive. From the results of the analyses for osteoclast specific estrogen receptor (ER) alphaknockout mice and the genome wide approach of ERalphabinding site, estrogen and SERMs can, at least in part, protect the bone mass by inducing the expression of Fas ligand and controling the life span of osteoclasts. More precise molecular mechanisms of the effect of SERM, especially in tissue/cell type specificity, may help to investigate new SERM, which is more specific and effective to treat post-menopausal osteoporosis.

  6. Osteoprotegerin-deficient male mice as a model for severe alveolar bone loss: comparison with RANKL-overexpressing transgenic male mice.

    Science.gov (United States)

    Koide, Masanori; Kobayashi, Yasuhiro; Ninomiya, Tadashi; Nakamura, Midori; Yasuda, Hisataka; Arai, Yoshinori; Okahashi, Nobuo; Yoshinari, Nobuo; Takahashi, Naoyuki; Udagawa, Nobuyuki

    2013-02-01

    Periodontitis, an inflammatory disease of periodontal tissues, is characterized by excessive alveolar bone resorption. An increase in the receptor activator of nuclear factor-κB ligand (RANKL) to osteoprotegerin (OPG) ratio is thought to reflect the severity of periodontitis. Here, we examined alveolar bone loss in OPG-deficient (OPG(-/-)) mice and RANKL-overexpressing transgenic (RANKL-Tg) mice. Alveolar bone loss in OPG(-/-) mice at 12 weeks was significantly higher than that in RANKL-Tg mice. OPG(-/-) but not RANKL-Tg mice exhibited severe bone resorption especially in cortical areas of the alveolar bone. An increased number of osteoclasts was observed in the cortical areas in OPG(-/-) but not in RANKL-Tg mice. Immunohistochemical analyses showed many OPG-positive signals in osteocytes but not osteoblasts. OPG-positive osteocytes in the cortical area of alveolar bones and long bones were abundant in both wild-type and RANKL-Tg mice. This suggests the resorption in cortical bone areas to be prevented by OPG produced locally. To test the usefulness of OPG(-/-) mice as an animal model for screening drugs to prevent alveolar bone loss, we administered an antimouse RANKL antibody or risedronate, a bisphosphonate, to OPG(-/-) mice. They suppressed alveolar bone resorption effectively. OPG(-/-) mice are useful for screening therapeutic agents against alveolar bone loss.

  7. Role of osteocytes in multiple myeloma bone disease

    Science.gov (United States)

    Delgado-Calle, Jesus; Bellido, Teresita; Roodman, G. David

    2014-01-01

    Purpose of review Despite the increased knowledge of osteocyte biology, the contribution of this most abundant bone cell to the development and progression of multiple myeloma in bone is practically unexplored. Recent findings Multiple myeloma bone disease is characterized by exacerbated bone resorption and the presence of osteolytic lesions that do not heal because of a concomitant reduction in bone formation. Osteocytes produce molecules that regulate both bone formation and resorption. Recent findings suggest that the life span of osteocytes is compromised in multiple myeloma patients with bone lesions. In addition, multiple myeloma cells affect the transcriptional profile of osteocytes by upregulating the production of pro-osteoclastogenic cytokines, stimulating osteoclast formation and activity. Further, patients with active multiple myeloma have elevated circulating levels of sclerostin, a potent inhibitor of bone formation which is specifically expressed by osteocytes in bone. Summary Understanding the contribution of osteocytes to the mechanisms underlying the skeletal consequences of multiple myeloma bone disease has the potential to provide important new therapeutic strategies that specifically target multiple myeloma–osteocyte interactions. PMID:25289928

  8. The Effect of Estrogen on the Restoration of Bone Mass and Bone Quality in Ovariectomized Rats

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To evaluate the effect of estrogen on its ability to restore the bone mass and bone quality in ovariectomized rats by examining the changes of bone morphology and histomorphometry, 3month-old rats were divided randomly into 4 groups: normal control, ovariectomized (OVX), shamoperated (Sham-O) and OVX plus estrogen (OVX+E2). Treatment initiated from the day 8 weeks after operation and continued for 12 weeks. Bone morphology and histomorphometry were examined afterwards. Results showed that comparing to control group, the trabecular bone in OVX appeared thinner and reduced in the amount. The connectivity between trabecula was decreased and the structure disordered. The free-end of trabecula was increased. The cavity of bone marrow enlarged. After treatment with estrogen, above changes improved remarkably by different degree, although did not reach the normal face. The bone histomorphometry results damonstrated that estrogen treatment increased bone mass and the amount of trabecula by 129% and 132% respectively (P<0. 05). The activity of bone resorption decreased significantly and the rate of bone formation increased to 203 %. These results suggest that treatment of ovariectomized rats with estrogen can not only increase bone mass, also improve the bone structure and enhance the property of bone mechanics.

  9. Longitudinal assessment of in vivo bone dynamics in a mouse tail model of postmenopausal osteoporosis.

    Science.gov (United States)

    Lambe