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Sample records for alveolar bone remodeling

  1. [Bone and Calcium Metabolisms Associated with Dental and Oral-Maxillofacial Diseases. Bone remodeling and alveolar bone homeostasis].

    Science.gov (United States)

    Nakashima, Tomoki

    2015-08-01

    Bone, which support motile organ and periodontal tissue, is renewing throughout our life. This restructuring process is called "bone remodeling" , and osteoclasts and osteoblasts play a crucial role in this process. Bone remodeling is important not only for normal bone mass and strength, but also for mineral homeostasis. Bone remodeling is stringently regulated by communication between bone component cells such as osteoclasts, osteoblasts and osteocytes. An imbalance of this process is often linked to various bone diseases. Alveolar bone remodeling is directly influenced by occlusal force from the teeth. Thus, the elucidation of the regulatory mechanisms involved in alveolar bone remodeling is critical for a deeper understanding of the maintenance of healthy tooth and dental disease.

  2. Zanthoxylum piperitum reversed alveolar bone loss of periodontitis via regulation of bone remodeling-related factors.

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    Kim, Mi Hye; Lee, Hye Ji; Park, Jung-Chul; Hong, Jongki; Yang, Woong Mo

    2017-01-04

    Zanthoxylum piperitum (ZP) has been used to prevent toothache in East Asia. In this study, we investigated the effects of ZP on periodontitis along with alveolar bone loss. Twenty-eight male Sprague-Dawley rats were assigned into 4 groups; non-ligated (NOR), ligated and treated vehicle (CTR), ligated and treated 1mg/mL ZP (ZP1), and ligated and treated 100mg/mL ZP (ZP100). Sterilized 3-0 nylon ligature was placed into the subgingival sulcus around the both sides of mandibular first molar. After topical application of 1 and 100mg/mL ZP for 2 weeks, mandibles was removed for histology. In addition, SaOS-2 osteoblast cells were treated 1, 10 and 100μg/mL ZP for 24h to analyze the expressions of alveolar bone-related markers. Several alveolar bone resorption pits, which indicate cementum demineralization were decreased by ZP treatment. Topical ZP treatment inhibited periodontitis-induced alveolar bone loss. In addition, there were significant reduction of osteoclastic activities following topical ZP treatment in periodontium. The expression of RANKL was decreased in SaOS-2 osteoblast cells by treating ZP, while that of OPG was increased. ZP treatment increased the expressions of Runx2 and Osterix in SaOS-2 cells. In summary, ZP treatment inhibited alveolar bone loss as well as maintained the integrity of periodontal structures via regulation of bone remodeling. ZP may be a therapeutic target for treating periodontitis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. A possible etiology for the dilaceration and flexion of permanent tooth roots relative to bone remodeling gradients in alveolar bone

    OpenAIRE

    2014-01-01

    Introduction: Trauma, altered tooth germ position and delayed tooth eruption have been hypothesized as possible causes of tooth root dilacerations and flexion, however these anatomical variations appear more commonly associated with posterior teeth and absence of traumatic history. The Hypothesis: Postulated is that tooth root dilaceration or flexion may be a result of tooth root sheath displacement due to gradients of bone remodeling present within alveolar bone. Evaluation of the Hypothesis...

  4. A possible etiology for the dilaceration and flexion of permanent tooth roots relative to bone remodeling gradients in alveolar bone

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    Richard G Standerwick

    2014-01-01

    Full Text Available Introduction: Trauma, altered tooth germ position and delayed tooth eruption have been hypothesized as possible causes of tooth root dilacerations and flexion, however these anatomical variations appear more commonly associated with posterior teeth and absence of traumatic history. The Hypothesis: Postulated is that tooth root dilaceration or flexion may be a result of tooth root sheath displacement due to gradients of bone remodeling present within alveolar bone. Evaluation of the Hypothesis: Alveolar bone displays bone remodeling gradients between coronal, apical and basal sections which affect bone plasticity. As a tooth is erupting or experiences delayed eruption, there are other relative dento-skeletal alterations occurring, such as the mesial drift of the dentition and transverse growth of the maxilla. It is plausible that during the physiologic and growth related alteration of the alveolar and basal bones, portions of developing tooth could be found within one or more of the plasticity zones, contributing to alteration of the root sheath and tooth root dilaceration.

  5. A histomorphometric study of alveolar bone modeling and remodeling in mice fed a boron-deficient diet

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    Background and Objective: Emerging evidence indicates that boron (B) plays a role in bone formation and maintenance. Thus, a study was performed to determine whether dietary B-deficiency affects periodontal alveolar bone modeling and remodeling. Material and Methods: Weanling Swiss mice (n=30) were ...

  6. The osteogenetic rate in alveolar bone remodeling induced by distraction osteogenesis of the periodontal ligament

    Institute of Scientific and Technical Information of China (English)

    WANG Shuang; FENG Pei-xun; GUO Xiong; ZHOU Hong

    2006-01-01

    Objective: To observe osteogenetic rate of alveolar bone on the tension side in orthodontic tooth movement through distraction osteogenesis of the periodental ligament quantificationally. Methods:The experiment was carried in 6 dogs. The left side of jaws of each one was set as test or control side, and the other side was control or test side. On the control side, the first premorlar was moved by traditional method on the test side. A self-made distraction device was used on the test side. The newly formed alveolar bone on the tension side of moved tooth was labeled by serial tetracycline fluorochrome. Sections were observed by fluorescence microscope and pictured. Newly formed bone was measured by computer image analysis. Results: The quantity of newly formed bone was significantly different between the two methods. Newly formed bone in rapid tooth movement by distraction osteogenesis of the periodental ligament was more than that in traditional method. Conclusion: The distraction through periodental ligament could induce more rapid bone formation and excite higher osteogenetic activity than traditional method.

  7. Immunolocalization of CSF-1, RANKL and OPG in the enamel-related periodontium of the rat incisor and their implications for alveolar bone remodeling.

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    Neves, J S; Salmon, C R; Omar, N F; Narvaes, E A O; Gomes, J R; Novaes, P D

    2009-07-01

    The enamel-related periodontium (ERP) in rat incisors is related to bone resorption. In these teeth the face of the socket related to the enamel is continuously removed at the inner side and newly formed at the outer side. CSF-1, RANKL and OPG are regulatory molecules essential for osteoclastogenesis. To verify the effects of impeded eruption on bone remodeling, the tooth eruption was prevented by immobilization of lower rat incisor and CSF-1, RANKL and OPG distribution in the ERP was analyzed after 18 days of immobilization and in normal eruption. The region of the alveolar crest of the rat incisor was used. Immunohistochemistry and tartrate-resistant acid phosphatase (TRAP) were performed. The immunostaining of the dental follicle was quantified using Leica QWin software. Positive-TRAP osteoclasts were counted, and both groups were compared. In the normal incisor, the number of osteoclasts was significantly greater than in the immobilized tooth. In the dental follicle, there was no significant difference in the immunostaining intensity for CSF-1 and OPG between the groups (p > 0.05), but for RANKL the immobilized incisor group showed immunostaining intensity smaller than the normal incisor group (p incisor, modify the RANKL/OPG ratio, in the presence of CSF-1, altering the metabolism of cells that participate in the bone remodeling.

  8. Alveolar bone grafting

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    Lilja Jan

    2009-10-01

    Full Text Available In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft.

  9. Remodeling dynamics in the alveolar process in skeletally mature dogs.

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    Huja, Sarandeep S; Fernandez, Soledad A; Hill, Kara J; Li, Yan

    2006-12-01

    Bone turnover rates can be altered by metabolic and mechanical demands. Due to the difference in the pattern of loading, we hypothesized that there are differences in bone remodeling rates between the maxillary and mandibular alveolar processes. Furthermore, in a canine model, the alveolar process of teeth that lack contact (e.g., second premolars) would have a different turnover rate than bone supporting teeth with functional contact (e.g., first molars). Six skeletally mature male dogs were given a pair of calcein labels. After sacrifice, specimens representing the anterior and posterior locations of both jaws were prepared for examination by histomorphometric methods to evaluate the bone volume/total volume (BV/TV; %), bone volume (mm2), mineral apposition rate (MAR; microm/day), and bone formation rate (BFR; %/year) in the alveolar process. There were no significant differences (P>0.05) in the BV/TV within the jaws. The bone volume within the alveolar process of the mandible was 2.8-fold greater than in the maxilla. The MAR was not significantly different between the jaws and anteroposterior locations. However, the BFR was significantly (Parchitecture.

  10. Experiment K-310: The effect of space flight on ostenogenesis and dentinogenesis in the mandible of rats. Supplement 1: The effects of space flight on alveolar bone modeling and remodeling in the rat mandible

    Science.gov (United States)

    Van, P. T.; Vignery, A.; Bacon, R.

    1981-01-01

    The histomorphometric study of alveolar bone, a non-weight-bearing bone submitted mainly to the mechanical stimulations of mastication, showed that space flight decreases the remodeling activity but does not induce a negative balance between resorption and formation. The most dramatic effect of space flight has been observed along the periosteal surface, and especially in areas not covered with masticatory muscles, where bone formation almost stopped completely during the flight period. This bone, having been submitted to the same mechanical forces in the flight animals and the controls, leads to the conclusion that factors other than mechanical loading might be involved in the decreased bone formation during flight.

  11. Bmp2 and Bmp4 accelerate alveolar bone development.

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    Ou, Mingming; Zhao, Yibing; Zhang, Fangming; Huang, Xiaofeng

    2015-06-01

    Alveolar bone remodeling is a continuous process that takes place during development and in response to various physiological and pathological stimuli. However, detailed knowledge regarding the underlying mechanisms involved in alveolar bone development is still lacking. This study aims at improving our understanding of alveolar bone formation and the role of bone morphogenetic proteins (Bmps) in this process. Mice at embryonic (E) day 13.5 to postnatal (PN) day 15.5 were selected to observe the process of alveolar bone development. Alveolar bone development was found to be morphologically observable at E14.5. Molar teeth isolated from mice at PN7.5 were pretreated with Bmp2, Bmp4, Noggin, or BSA, and grafted subcutaneously into mice. The subcutaneously implanted tooth germs formed alveolar bone indicating the role of the dental follicle in alveolar bone development. Alveolar bone formation was increased after pretreatment with Bmp2 and Bmp4, but not with Noggin. Gene expression levels in dental follicle cells from murine molars were also determined by real-time RT-PCR. The expression levels of Runx2, Bsp, and Ocn were significantly higher in dental follicle cells cultured with Bmp2 or Bmp4, and significantly lower in those cultured with Noggin when compared with that of the BSA controls. Our results suggest that the dental follicle participates in alveolar bone formation and Bmp2/4 appears to accelerate alveolar bone development.

  12. Immunoregulation of bone remodelling.

    Science.gov (United States)

    Singh, Ajai; Mehdi, Abbass A; Srivastava, Rajeshwer N; Verma, Nar Singh

    2012-05-01

    Remodeling, a continuous physiological process maintains the strength of the bones, which maintains a delicate balance between bone formation and resorption process. This review gives an insight to the complex interaction and correlation between the bone remodeling and the corresponding changes in host immunological environment and also summarises the most recent developments occuring in the understanding of this complex field. T cells, both directly and indirectly increase the expression of receptor activator of nuclear factor kB ligand (RANKL); a vital step in the activation of osteoclasts, thus positively regulates the osteoclastogenesis. Though various cytokines, chemikines, transcription factors and co-stimulatory molecules are shared by both skeletal and immune systems, but researches are being conducted to establish and analyse their role and / or control on this complex but vital process. The understanding of this part of research may open new horizons in the management of inflammatory and autoimmune diseases, resulting into bone loss and that of osteoporosis also.

  13. Alveolar bone loss in osteoporosis: a loaded and cellular affair?

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    Jonasson, Grethe; Rythén, Marianne

    2016-01-01

    Maxillary and mandibular bone mirror skeletal bone conditions. Bone remodeling happens at endosteal surfaces where the osteoclasts and osteoblasts are situated. More surfaces means more cells and remodeling. The bone turnover rate in the mandibular alveolar process is probably the fastest in the body; thus, the first signs of osteoporosis may be revealed here. Hormones, osteoporosis, and aging influence the alveolar process and the skeletal bones similarly, but differences in loading between loaded, half-loaded, and unloaded bones are important to consider. Bone mass is redistributed from one location to another where strength is needed. A sparse trabeculation in the mandibular premolar region (large intertrabecular spaces and thin trabeculae) is a reliable sign of osteopenia and a high skeletal fracture risk. Having dense trabeculation (small intertrabecular spaces and well-mineralized trabeculae) is generally advantageous to the individual because of the low fracture risk, but may imply some problems for the clinician.

  14. Alveolar bone loss in osteoporosis: a loaded and cellular affair?

    Science.gov (United States)

    Jonasson, Grethe; Rythén, Marianne

    2016-01-01

    Maxillary and mandibular bone mirror skeletal bone conditions. Bone remodeling happens at endosteal surfaces where the osteoclasts and osteoblasts are situated. More surfaces means more cells and remodeling. The bone turnover rate in the mandibular alveolar process is probably the fastest in the body; thus, the first signs of osteoporosis may be revealed here. Hormones, osteoporosis, and aging influence the alveolar process and the skeletal bones similarly, but differences in loading between loaded, half-loaded, and unloaded bones are important to consider. Bone mass is redistributed from one location to another where strength is needed. A sparse trabeculation in the mandibular premolar region (large intertrabecular spaces and thin trabeculae) is a reliable sign of osteopenia and a high skeletal fracture risk. Having dense trabeculation (small intertrabecular spaces and well-mineralized trabeculae) is generally advantageous to the individual because of the low fracture risk, but may imply some problems for the clinician. PMID:27471408

  15. Biological Events in Periodontal Ligament and Alveolar Bone Associated with Application of Orthodontic Forces

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    L. Feller

    2015-01-01

    Full Text Available Orthodontic force-induced stresses cause dynamic alterations within the extracellular matrix and within the cytoskeleton of cells in the periodontal ligament and alveolar bone, mediating bone remodelling, ultimately enabling orthodontic tooth movement. In the periodontal ligament and alveolar bone, the mechanically induced tensile strains upregulate the expression of osteogenic genes resulting in bone formation, while mechanically induced compressive strains mediate predominantly catabolic tissue changes and bone resorption. In this review article we summarize some of the currently known biological events occurring in the periodontal ligament and in the alveolar bone in response to application of orthodontic forces and how these facilitate tooth movement.

  16. 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

  17. 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

  18. Tooth loss and alveolar remodeling in Sinosaurus triassicus (Dinosauria: Theropoda) from the Lower Jurassic strata of the Lufeng Basin, China

    Institute of Scientific and Technical Information of China (English)

    XING LiDa; BELL Phil R; ROTHSCHILD Bruce M; RAN Hao; ZHANG JianPing; DONG ZhiMing; ZHANG Wei

    2013-01-01

    Pathological or traumatic loss of teeth often results in the resorption and remodeling of the affected alveoli in mammals.However,instances of alveolar remodeling in reptiles are rare.A remodeled alveolus in the maxilla of the Chinese theropod Sinosaurus (Lower Jurassic Lower Lufeng Formation) is the first confirmed example of such dental pathology in a dinosaur.Given the known relationship between feeding behavior and tooth damage in theropods (teeth with spalled enamel,tooth crowns embedded in bone) and the absence of dentary,maxillary,and premaxillary osteomyelitis,traumatic loss of a tooth is most likely the cause of alveolar remodeling.Based on the extent of remodeling,the injury and subsequent tooth loss were non-fatal in this individual.

  19. 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.

  20. Bone remodeling as a spatial evolutionary game.

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    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.

  1. Silver Nanoparticles in Alveolar Bone Surgery Devices

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    Stefano Sivolella

    2012-01-01

    Full Text Available Silver (Ag ions have well-known antimicrobial properties and have been applied as nanostrategies in many medical and surgical fields, including dentistry. The use of silver nanoparticles (Ag NPs may be an option for reducing bacterial adhesion to dental implant surfaces and preventing biofilm formation, containing the risk of peri-implant infections. Modifying the structure or surface of bone grafts and membranes with Ag NPs may also prevent the risk of contamination and infection that are common when alveolar bone augmentation techniques are used. On the other hand, Ag NPs have revealed some toxic effects on cells in vitro and in vivo in animal studies. In this setting, the aim of the present paper is to summarize the principle behind Ag NP-based devices and their clinical applications in alveolar bone and dental implant surgery.

  2. 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

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

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    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.

  4. Histologic, Clinical, and Radiologic Findings of Alveolar Bone Expansion and Osteomyelitis of the Jaws in Cats.

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    Bell, C M; Soukup, J W

    2015-09-01

    The objective of this study was to characterize clinical, radiologic, and histologic patterns of alveolar bone expansion and osteomyelitis in cats. Based on case materials submitted as surgical biopsy specimens, alveolar bone pathology was diagnosed in 28 cats. These cats had a total of 37 oral lesions with clinical and radiologic changes that involved bone and/or teeth, including periodontitis, bone expansion, tooth resorption, and/or chronic osteomyelitis; 32 lesions were evaluated by histopathology. Canine teeth were affected in 19 cats (27 affected teeth), with bilateral lesions in 5 (26.3%) cats. The caudal premolar and/or molar regions were affected in 10 cats (10 affected sites). All biopsy sites evaluated by a review of clinical images and/or radiographs had evidence of periodontitis. Clinical photographs showed expansion of alveolar bone in 13 of 16 (81%) biopsy sites evaluated. Radiologically, rarifying osseous proliferation of alveolar bone was seen at 26 of 27 (96%) biopsy sites, and tooth resorption occurred at 15 of 18 (83%) sites. Histologically, the tissue samples from canine sites had compressed trabeculae of mature remodeled bone, loose fibrous stroma with paucicellular inflammation, and mild proliferation of woven bone. Tissue samples from the premolar/molar biopsy sites were often highly cellular with mixed lymphoplasmacytic and chronic suppurative inflammation, ulceration with granulation tissue, and robust proliferation of woven bone. Alveolar bone expansion and osteomyelitis in cats occurs in conjunction with periodontal inflammation and frequently with tooth resorption.

  5. 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...

  6. Horizontal alveolar bone loss: A periodontal orphan

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    Jayakumar A

    2010-01-01

    Full Text Available Background: Attempts to successfully regenerate lost alveolar bone have always been a clinician′s dream. Angular defects, at least, have a fairer chance, but the same cannot be said about horizontal bone loss. The purpose of the present study was to evaluate the prevalence of horizontal alveolar bone loss and vertical bone defects in periodontal patients; and later, to correlate it with the treatment modalities available in the literature for horizontal and vertical bone defects. Materials and Methods: The study was conducted in two parts. Part I was the radiographic evaluation of 150 orthopantomographs (OPGs (of patients diagnosed with chronic periodontitis and seeking periodontal care, which were digitized and read using the AutoCAD 2006 software. All the periodontitis-affected teeth were categorized as teeth with vertical defects (if the defect angle was ≤45° and defect depth was ≥3 mm or as having horizontal bone loss. Part II of the study comprised search of the literature on treatment modalities for horizontal and vertical bone loss in four selected periodontal journals. Results: Out of the 150 OPGs studied, 54 (36% OPGs showed one or more vertical defects. Totally, 3,371 teeth were studied, out of which horizontal bone loss was found in 3,107 (92.2% teeth, and vertical defects were found only in 264 (7.8% of the teeth, which was statistically significant (P<.001. Search of the selected journals revealed 477 papers have addressed the treatment modalities for vertical and horizontal types of bone loss specifically. Out of the 477 papers, 461 (96.3% have addressed vertical bone loss, and 18 (3.7% have addressed treatment options for horizontal bone loss. Two papers have addressed both types of bone loss and are included in both categories. Conclusion: Horizontal bone loss is more prevalent than vertical bone loss but has been sidelined by researchers as very few papers have been published on the subject of regenerative treatment

  7. Prevention of alveolar bone loss in an osteoporotic animal model via interference of semaphorin 4d.

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    Zhang, Y; Wei, L; Miron, R J; Zhang, Q; Bian, Z

    2014-11-01

    Semaphorin 4d (Sema4d) has been proposed as a novel target gene for the treatment of osteoporosis. Recently, we fabricated a site-specific bone-targeting system from polymeric nanoparticles that demonstrates an ability to prevent bone loss in an osteoporotic model by interfering with Sema4d gene expression using small interference RNA (siRNA) molecules. The aim of the present investigation was to determine the effects of this targeting system on the periodontium, an area of high bone turnover. We demonstrated, by single photon emission computed tomography, that intravenous injection of this molecule in ovariectomized Balb/C mice is able to target alveolar bone peaking 4 hr post-injection. We then compared, by histological analysis, the bone volume/total volume (BV/TV), alveolar bone height loss, immunohistochemical expression of Sema4d, and total number of osteoclasts in mandibular alveolar bone. Four treatment modalities were compared as follows: (1) sham-operated, (2) OVX-operated, (3) OVX+estrogen replacement therapy, and (4) OVX+siRNA-Sema4d animals. The results from the present study demonstrate that an osteoporotic condition significantly increases alveolar bone height loss, and that the therapeutic effects via bone-targeting systems featuring interference of Sema4d are able to partly counteract alveolar bone loss caused by osteoporosis. While the future therapeutic demand for the large number of patients suffering from osteoporosis faces many challenges, we demonstrate within the present study an effective drug-delivery moiety with anabolic effects on the bone remodeling cycle able to locate and target alveolar bone regeneration.

  8. Bone Remodelling Markers in Rheumatoid Arthritis

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    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.

  9. On the development of an integrated bone remodeling law for orthodontic tooth movements models using the Finite Element Method.

    OpenAIRE

    Mengoni, Marlène

    2012-01-01

    One of the guiding principles in orthodontics is to gradually impose progressive and irreversible bone deformations due to remodeling using specific force systems on the teeth. Bone remodeling leads the teeth into new positions with two tissues having a major influence: the periodontal ligament and the alveolar bone. Their mechanical and biological/physiological reactions to orthodontic forces are tightly linked. This mechanical biological coupling can be treated in biomechanical mod...

  10. Interactions between remodelling, architecture and tissue properties in cancellous bone

    OpenAIRE

    Linden, Jacqueline

    2003-01-01

    textabstractThe aim of the research projects described in this thesis was to gain more insight in the regulation of bone remodeling and in the interactions between bone remodeling, architecture and bone tissue properties. The most striking changes during aging and osteoporosis take place in cancellous bone. For this reason, the research presented in this thesis focussed on bone remodeling in cancellous bone. We used computer modeling, finite element calculations and in vivo labeled bone speci...

  11. Nostril Base Augmentation Effect of Alveolar Bone Graft

    Directory of Open Access Journals (Sweden)

    Woojin Lee

    2013-09-01

    Full Text Available BackgroundThe aims of alveolar bone grafting are closure of the fistula, stabilization of the maxillary arch, support for the roots of the teeth adjacent to the cleft on each side. We observed nostril base augmentation in patients with alveolar clefts after alveolar bone grafting. The purpose of this study was to evaluate the nostril base augmentation effect of secondary alveolar bone grafting in patients with unilateral alveolar cleft.MethodsRecords of 15 children with alveolar clefts who underwent secondary alveolar bone grafting with autogenous iliac cancellous bone between March of 2011 and May of 2012 were reviewed. Preoperative and postoperative worm's-eye view photographs and reconstructed three-dimensional computed tomography (CT scans were used for photogrammetry. The depression of the nostril base and thickness of the philtrum on the cleft side were measured in comparison to the normal side. The depression of the cleft side pyriform aperture was measured in comparison to the normal side on reconstructed three-dimensional CT.ResultsSignificant changes were seen in the nostril base (P=0.005, the philtrum length (P=0.013, and the angle (P=0.006. The CT measurements showed significant changes in the pyriform aperture (P<0.001 and the angle (P<0.001.ConclusionsAn alveolar bone graft not only fills the gap in the alveolar process but also augments the nostril base after surgery. In this study, only an alveolar bone graft was performed to prevent bias from other procedures. Nostril base augmentation can be achieved by performing alveolar bone grafts in children, in whom invasive methods are not advised.

  12. 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.

  13. Vestibuloplasty after secondary alveolar bone grafting.

    Science.gov (United States)

    Iino, M; Fukuda, M; Murakami, K; Horiuchi, T; Niitsu, K; Seto, K

    2001-11-01

    This paper introduces a surgical technique for vestibuloplasty after secondary alveolar bone grafting of patients with cleft lip and palate (CLP). This paper also reports on the patients who underwent this modified vestibuloplasty. The vestibuloplasty technique described in this paper consists of: (1) reduction of submucosal scar tissue of the upper lip, (2) V-Y plasty of the superficial mucosa, (3) placement of horizontal mattress sutures between nostril floor skin and freed marginal mucosa, (4) application of artificial skin to cover the exposed periosteal surface, and (5) use of a removable retention splint. This surgical procedure appears to be very useful for patients with CLP. The technique enables the surgeon to obtain an adequate sulcus depth around the graft area. In addition, this technique releases the mucosal scar contraction and improves the shape and mobility of the upper lip.

  14. Nostril Base Augmentation Effect of Alveolar Bone Graft

    Directory of Open Access Journals (Sweden)

    Woojin Lee

    2013-09-01

    Full Text Available Background The aims of alveolar bone grafting are closure of the fistula, stabilization ofthe maxillary arch, support for the roots of the teeth adjacent to the cleft on each side.We observed nostril base augmentation in patients with alveolar clefts after alveolar bonegrafting. The purpose of this study was to evaluate the nostril base augmentation effect ofsecondary alveolar bone grafting in patients with unilateral alveolar cleft.Methods Records of 15 children with alveolar clefts who underwent secondary alveolar bonegrafting with autogenous iliac cancellous bone between March of 2011 and May of 2012 werereviewed. Preoperative and postoperative worm’s-eye view photographs and reconstructedthree-dimensional computed tomography (CT scans were used for photogrammetry. Thedepression of the nostril base and thickness of the philtrum on the cleft side were measuredin comparison to the normal side. The depression of the cleft side pyriform aperture wasmeasured in comparison to the normal side on reconstructed three-dimensional CT.Results Significant changes were seen in the nostril base (P=0.005, the philtrum length(P=0.013, and the angle (P=0.006. The CT measurements showed significant changes in thepyriform aperture (P<0.001 and the angle (P<0.001.Conclusions An alveolar bone graft not only fills the gap in the alveolar process but alsoaugments the nostril base after surgery. In this study, only an alveolar bone graft was performedto prevent bias from other procedures. Nostril base augmentation can be achieved byperforming alveolar bone grafts in children, in whom invasive methods are not advised.

  15. [Distraction osteogenesis of deficient alveolar bone prior to dental rehabilitation].

    Science.gov (United States)

    Shilo, D; Emodi, O; Aizenbud, D; Rachmiel, A

    2015-07-01

    Implant supported rehabilitation has become very common in treatment plans nowadays, yet many patients lack the vertical and horizontal bone dimensions required for endosseous implant insertion. Distraction osteogenesis is a technique in which bone is generated by progressive elongation of two bone fragments following an osteotomy or corticotomy. Distraction osteogenesis of the alveolar ridge as a treatment modality in implant dentistry is a very useful technique that allows for adequate bone formation suitable for implant insertion. Alveolar distraction can be unidirectional, bidirectional, multidirectional or horizontal. Alveolar distraction osteogenesis can be performed by using intraosseous distraction devices, intraosseous distraction implants or by extraosseous devices which are the most prevalent today. Distraction osteogenesis has many advantages such as gradual lengthening of the bone with no need for an autogenous bone graft and lack of the associated donor site morbidity as well as distraction of the surrounding soft tissue together with the transported bone. One of the major challenges when using alveolar distraction osteogenesis is controlling the vector of distraction, this problem should be further addressed in future researches. We describe different methods for alveolar distraction osteogenesis, including the surgical procedure, latency period, lengthening and consolidation period. We also discuss the advantages, disadvantages and complications of the method. In this manuscript a case of mandibular alveolar deficiency following mandibular fracture and loss of teeth and the alveolar bone is presented. This patient was treated by alveolar distraction osteogenesis with excellent results. This patient was later rehabilitated . using endosseous implants as demonstrated by radiographs. Alveolar distraction osteogenesis provides a method to regain both hard tissue and soft tissue without additional grafting and is an efficient modality in cases of medium

  16. Osteoblast recruitment routes in human cancellous bone remodeling

    DEFF Research Database (Denmark)

    Kristensen, Helene B; Levin Andersen, Thomas; Marcussen, Niels

    2014-01-01

    It is commonly proposed that bone forming osteoblasts recruited during bone remodeling originate from bone marrow perivascular cells, bone remodeling compartment canopy cells, or bone lining cells. However, an assessment of osteoblast recruitment during adult human cancellous bone remodeling......-terminal peptide versus osterix, and (ii) canopy cell densities, found to decline with age, and canopy-capillary contacts above eroded surfaces correlated positively with osteoblast density on bone-forming surfaces. Furthermore, we showed that bone remodeling compartment canopies arise from a mesenchymal envelope...

  17. Postoperative morbidity after reconstruction of alveolar bone defects with chin bone transplants in cleft patients - 111 consecutive patients

    DEFF Research Database (Denmark)

    Andersen, Kristian; Nørholt, Sven Erik; Knudsen, Johan;

    Postoperative morbidity after reconstruction of alveolar bone defects with chin bone transplants in cleft patients - 111 consecutive patients......Postoperative morbidity after reconstruction of alveolar bone defects with chin bone transplants in cleft patients - 111 consecutive patients...

  18. Hydroxyapatite-calcium sulfate-hyaluronic acid composite encapsulated with collagenase as bone substitute for alveolar bone regeneration.

    Science.gov (United States)

    Subramaniam, Sadhasivam; Fang, Yen-Hsin; Sivasubramanian, Savitha; Lin, Feng-Huei; Lin, Chun-pin

    2016-01-01

    Periodontitis is a very severe inflammatory condition of the periodontium that progressively damages the soft tissue and destroys the alveolar bone that supports the teeth. The bone loss is naturally irreversible because of limited reparability of the teeth. Advancement in tissue engineering provides an effective regeneration of osseous defects with suitable dental implants or tissue-engineered constructs. This study reports a hydroxyapatite, calcium sulfate hemihydrate and hyaluronic acid laden collagenase (HAP/CS/HA-Col) as a bone substitute for the alveolar bone regeneration. The composite material was mechanically tested and the biocompatibility was evaluated by WST-1 assay. The in vivo bone formation was assessed in rat with alveolar bone defects and the bone augmentation by the HAP/CS/HA-Col composite was confirmed by micro-CT images and histological examination. The mechanical strength of 6.69 MPa with excellent biocompatibility was obtained for the HAP/CS/HA-Col composite. The collagenase release profile had facilitated the acceleration of bone remodeling process and it was confirmed by the findings of micro-CT and H&E staining. The bone defects implanted with HAP/CS/HA composite containing 2 mg/mL type I collagenase have shown improved new bone formation with matured bone morphology in comparison with the HAP/CS/HA composite that lacks the collagenase and the porous hydroxyapatite (p-HAP) granules. The said findings demonstrated that the collagenase inclusion in HAP/CS/HA composite is a feasible approach for the alveolar bone regeneration and the same design can also be applied to other defective tissues.

  19. Alveolar cleft closure with iliac bone graft: A case report.

    Directory of Open Access Journals (Sweden)

    Tichvy Tammama

    2017-04-01

    Conclusion: The timing of alveolar bone grafting usually associated with the state of the developing of dentition. Post operative management is important to get a good result, and to prevent any complications.

  20. Impact of the Oral Commensal Flora on Alveolar Bone Homeostasis

    OpenAIRE

    Irie, K; Novince, C.M.; Darveau, R. P.

    2014-01-01

    Homeostasis of healthy periodontal tissues is affected by innate and adaptive immunosurveillance mechanisms in response to the normal oral flora. Recent comparisons of germ-free (GF) and normal specific-pathogen-free (SPF) mice have revealed the impact of host immunosurveillance mechanisms in response to the normal oral flora on alveolar bone height. Prior reports that alveolar bone height is significantly less in normal SPF mice compared with their age- and strain-matched GF counterparts sug...

  1. Is there a relation between local bone quality as assessed on panoramic radiographs and alveolar bone level?

    Science.gov (United States)

    Nackaerts, Olivia; Gijbels, Frieda; Sanna, Anna-Maria; Jacobs, Reinhilde

    2008-03-01

    The aim was to explore the relation between radiographic bone quality on panoramic radiographs and relative alveolar bone level. Digital panoramic radiographs of 94 female patients were analysed (mean age, 44.5; range, 35-74). Radiographic density of the alveolar bone in the premolar region was determined using Agfa Musica software. Alveolar bone level and bone quality index (BQI) were also assessed. Relationships between bone density and BQI on one hand and the relative loss of alveolar bone level on the other were assessed. Mandibular bone density and loss of alveolar bone level were weakly but significantly negatively correlated for the lower premolar area (r = -.27). The BQI did not show a statistically significant relation to alveolar bone level. Radiographic mandibular bone density on panoramic radiographs shows a weak but significant relation to alveolar bone level, with more periodontal breakdown for less dense alveolar bone.

  2. Osteoclastogenesis in Local Alveolar Bone in Early Decortication-Facilitated Orthodontic Tooth Movement

    Science.gov (United States)

    Liu, Chang; Jiang, Yu-Xi; Qu, Hong; Li, Cui-Ying; Jiang, Jiu-Hui

    2016-01-01

    Objective In the current study, we aimed to investigate the effects of alveolar decortication on local bone remodeling, and to explore the possible mechanism by which decortication facilitates tooth movement. Materials and Methods Forty rabbits were included in the experiment. The left mandible was subjected to decortication-facilitated orthodontics, and the right mandible underwent traditional orthodontics as a control. The animals were sacrificed on the days 1, 3, 5, 7 and 14, after undergoing orthodontic procedures. Tooth movement was measured by Micro-CT, and the local periodontal tissues were investigated using H&E, Masson's trichrome and tartrate-resistant acid phosphatase (TRAP) staining. The mRNA levels of genes related to bone remodeling in the alveolar bone were analyzed using real-time PCR. Result On days 3, 5, 7 and 14, tooth movement was statistically accelerated by decortication (P < 0.05) and was accompanied by increased hyperemia. Despite the lack of new bone formation in both groups, more osteoclasts were noted in the decorticated group, with two peak counts (P < 0.05). The first peak count was consistent with the maximum values of ctsk and TRAP expression, and the second peak counts accompanied the maximum nfatc1 and jdp2 expression. The increased fra2 expression and the ratio of rankl/opg also accompanied the second peak counts. Conclusions Following alveolar decortication, osteoclastogenesis was initially induced to a greater degree than the new bone formation which was thought to have caused a regional acceleratory phenomenon (RAP). The amount of steoclastogenesis in the decorticated alveolar bone was found to have two peaks, perhaps due to attenuated local resistance. The first peak count in osteoclasts may have been due to previously existing osteoclast precursors, whereas the second may represent the differentiation of peripheral blood mononuclear cells which came from circulation as the result of hyperemia. PMID:27096621

  3. Segment distraction to reduce a wide alveolar cleft before alveolar bone grafting.

    NARCIS (Netherlands)

    Binger, T.; Katsaros, C.; Rucker, M.; Spitzer, W.J.

    2003-01-01

    OBJECTIVE: To demonstrate a method for reduction of wide alveolar clefts prior to bone grafting. This method aims to facilitate bone grafting and achieve adequate soft tissue coverage of the graft with attached gingiva. CASE REPORT: Treatment of a patient with bilateral cleft lip and palate with a s

  4. Development of Bone Remodeling Model for Spaceflight Bone Physiology Analysis

    Science.gov (United States)

    Pennline, James A.; Werner, Christopher R.; Lewandowski, Beth; Thompson, Bill; Sibonga, Jean; Mulugeta, Lealem

    2015-01-01

    Current spaceflight exercise countermeasures do not eliminate bone loss. Astronauts lose bone mass at a rate of 1-2% a month (Lang et al. 2004, Buckey 2006, LeBlanc et al. 2007). This may lead to early onset osteoporosis and place the astronauts at greater risk of fracture later in their lives. NASA seeks to improve understanding of the mechanisms of bone remodeling and demineralization in 1g in order to appropriately quantify long term risks to astronauts and improve countermeasures. NASA's Digital Astronaut Project (DAP) is working with NASA's bone discipline to develop a validated computational model to augment research efforts aimed at achieving this goal.

  5. Histamine in regulation of bone remodeling processes

    Directory of Open Access Journals (Sweden)

    Marek Wiercigroch

    2013-08-01

    Full Text Available Bone remodeling is under autocrine, paracrine, endocrine and central nervous system control. One of the potential endogenous factors affecting bone remodeling is histamine, an endogenous amine which acts as a mediator of allergic reactions and neuromediator, and induces production of gastric acid. Histamine H1 receptor antagonists are widely used in the treatment of allergic conditions, H2 receptor antagonists in peptic ulcer disease, and betahistine (an H3 receptor antagonist and H1 receptor agonist is used in the treatment of Ménière’s disease.Excess histamine release in mastocytosis and allergic diseases may lead to development of osteoporosis. Clinical and population-based studies on the effects of histamine receptor antagonists on the skeletal system have not delivered unequivocal results.Expression of mRNA of histamine receptors has been discovered in bone cells (osteoblasts and osteoclasts. Histamine synthesis has been demonstrated in osteoclast precursors. Histamine increases bone resorption both by direct effects on osteoclast precursors and osteoclasts, and indirectly, by increasing the expression of RANKL in osteoblasts. In in vivo studies, H1 and H2 receptor antagonists exerted protective effects on the bone tissue, although not in all experimental models. In the present article, in vitro and in vivo studies conducted so far, concerning the effects of histamine and drugs modifying its activity on the skeletal system, have been reviewed.

  6. Chondromodulin I Is a Bone Remodeling Factor

    Science.gov (United States)

    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 respect to formation was unexpectedly found in adult ChM-I−/− mice. Thus, the present study established that ChM-I is a bone remodeling factor. PMID:12509461

  7. 3D-CT evaluation of secondary alveolar bone grafts in alveolar clefts

    Energy Technology Data Exchange (ETDEWEB)

    Naitoh, Hiroshi; Nishimura, Yoshihiko [Kyoto Univ. (Japan). Graduate School of Medicine; Yamawaki, Yoshiroh [Kyoto Katsura Hospital (Japan); Morimoto, Naoki [Kobe City General Hospital (Japan)

    2002-07-01

    From 1994 to 2000, we treated 116 patients with cleft alveolus by secondary alveolar bone grafts, and 48 of them were evaluated morphologically with 3D-CT. The frequency of successful bony bridging was significantly higher in the group whose grafts were completely enveloped (including the anterior alveolar ridge) with a mucoperiosteal flap. The frequency was also significantly higher in the group who underwent bone grafts at the age of 13 or less, and canine eruptions did not influence the ratio. Some cases showed such an improved growth pattern of grafted bone that the shape of the affected maxilla resembled that of the normal side, after long-term follow-up observations. The growth increment was remarkable in anterior maxillary height. Orthodontic management guides the canine or incisor into the reconstructed area of the previous cleft. We surmise that the new occlusal position puts pressure on the grafted bone and promotes further osteogenesis. These findings show that it is important to produce sufficient bony bridge to guide the canine or incisor, not the volume of grafted bone, in secondary alveolar bone grafts. Long-term follow-up observation, after more than 2-3 years, is also necessary to evaluate secondary alveolar bone grafts. (author)

  8. 牙弓/牙槽骨弓的塑形矫治——基于牙弓形态发育不良的儿童错(拾)畸形诊断与阻断治疗%Dental alveolar bone and dental arch remodeling in children: orthodontic diagnosis and treatments based on individual child arch development

    Institute of Scientific and Technical Information of China (English)

    李小兵

    2016-01-01

    The etiology of malocclusions basically involves both congenital and environmental factors. Malocclusion is the result of the abnormal development of the orofacial complex (including tooth, dental alveolar bone, upper and lower jaws). Early orthodontic interceptive treatments involve the elimination of all congenital and environmental factors that contribute to the malformation of the orofacial complex, as well as interrupt the deviated development of the orofacial complex and the occlusion. Early orthodontic interceptive treatments mainly aim to use children's growth potential to correct abnormal develop-ments of occlusions and orthodontically treat malocclusions more efficiently. The early orthodontic interceptive treatments include correcting the child's bad oral habits, training the abnormal functioned para-oral muscles, maintaining the normal eruptions of succeeding permanent teeth, applying interceptive treatments to the mal-developed teeth, and employing functional orthopedic treatments for abnormal growths of the upper and lower jaws. In orthodontics, correcting mal-positioned teeth is called orthodontic treatment, while rectifying the abnormal relationships of the upper and lower jaws is called functional orthopedic treatment. However, no clear definition is available as regards to the early orthodontic interceptive treatment of malocclusions caused by the deviated development of the dental alveolar bone. This new theory of "early dental alveolar bone and dental arch remodeling technique" was proposed by Professor Li Xiaobing of the Department of Pediatric Dentistry, Faculty of Pediatric Dentistry and Orthodontics in West China Hospital of Stomatology through his clinical analyses and investigation of his early orthodontic interceptive treatments. He defined the early orthodontic corrections of abnormal growth of dental alveolar bone as "remodel". The "early dental alveolar bone and dental arch remodeling theory and technique" is proved useful in

  9. Alveolar bone loss: mechanisms, potential therapeutic targets, and interventions.

    Science.gov (United States)

    Intini, G; Katsuragi, Y; Kirkwood, K L; Yang, S

    2014-05-01

    This article reviews recent research into mechanisms underlying bone resorption and highlights avenues of investigation that may generate new therapies to combat alveolar bone loss in periodontitis. Several proteins, signaling pathways, stem cells, and dietary supplements are discussed as they relate to periodontal bone loss and regeneration. RGS12 is a crucial protein that mediates osteoclastogenesis and bone destruction, and a potential therapeutic target. RGS12 likely regulates osteoclast differentiation through regulating calcium influx to control the calcium oscillation-NFATc1 pathway. A working model for RGS10 and RGS12 in the regulation of Ca(2+) oscillations during osteoclast differentiation is proposed. Initiation of inflammation depends on host cell-microbe interactions, including the p38 mitogen-activated protein kinase (MAPK) signaling pathway. Oral p38 inhibitors reduced lipopolysaccharide (LPS)-induced bone destruction in a rat periodontitis model but showed unsatisfactory safety profiles. The p38 substrate MK2 is a more specific therapeutic target with potentially superior tolerability. Furthermore, MKP-1 shows anti-inflammatory activity, reducing inflammatory cytokine biosynthesis and bone resorption. Multipotent skeletal stem cell (SSC) populations exist within the bone marrow and periosteum of long bones. These bone-marrow-derived SSCs and periosteum-derived SSCs have shown therapeutic potential in several applications, including bone and periodontal regeneration. The existence of craniofacial bone-specific SSCs is suggested based on existing studies. The effects of calcium, vitamin D, and soy isoflavone supplementation on alveolar and skeletal bone loss in post-menopausal women were investigated. Supplementation resulted in stabilization of forearm bone mass density and a reduced rate of alveolar bone loss over 1 yr, compared with placebo. Periodontal attachment levels were also well-maintained and alveolar bone loss suppressed during 24 wk of

  10. Locally Produced BDNF Promotes Sclerotic Change in Alveolar Bone after Nerve Injury

    Science.gov (United States)

    Ida-Yonemochi, Hiroko; Yamada, Yurie; Yoshikawa, Hiroyuki

    2017-01-01

    Brain-derived neurotrophic factor (BDNF), which is released due to nerve injury, is known to promote the natural healing of injured nerves. It is often observed that damage of mandibular canal induces local sclerotic changes in alveolar bone. We reported that peripheral nerve injury promotes the local production of BDNF; therefore, it was possible to hypothesize that peripheral nerve injury affects sclerotic changes in the alveolar bone. This study aimed to evaluate the effect of BDNF on osteogenesis using in vitro osteoblast-lineage cell culture and an in vivo rat osteotomy model. MC3T3-E1 cells were cultured with BDNF and were examined for cell proliferative activity, chemotaxis and mRNA expression levels of osteoblast differentiation markers. For in vivo study, inferior alveolar nerve (IAN) injury experiments and mandibular cortical osteotomy were performed using a rat model. In the osteotomy model, exogenous BDNF was applied to bone surfaces after corticotomy of the mandible, and we morphologically analyzed the new bone formation. As a result, mRNA expression of osteoblast differentiation marker, osteocalcin, was significantly increased by BDNF, although cell proliferation and migration were not affected. In the in vivo study, osteopontin-positive new bone formation was significantly accelerated in the BDNF-grafted groups, and active bone remodeling, involving trkB-positive osteoblasts and osteocytes, continued after 28 days. In conclusion, BDNF stimulated the differentiation of MC3T3-E1 cells and it promoted new bone formation and maturation. These results suggested that local BDNF produced by peripheral nerve injury contributes to accelerating sclerotic changes in the alveolar bone. PMID:28072837

  11. Classification of Alveolar Bone Destruction Patterns on Maxillary ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... The aim of this research was to classify alveolar bone defects in the ... 669 maxillary molars of 243 patients with periodontal bone loss were investigated on four aspects ...... about one-third (35.2%) of all defects.[28,29] Our ...

  12. Interactions between remodelling, architecture and tissue properties in cancellous bone

    NARCIS (Netherlands)

    J.C. van der Linden (Jacqueline)

    2003-01-01

    textabstractThe aim of the research projects described in this thesis was to gain more insight in the regulation of bone remodeling and in the interactions between bone remodeling, architecture and bone tissue properties. The most striking changes during aging and osteoporosis take place in cancello

  13. Interactions between remodelling, architecture and tissue properties in cancellous bone

    NARCIS (Netherlands)

    J.C. van der Linden (Jacqueline)

    2003-01-01

    textabstractThe aim of the research projects described in this thesis was to gain more insight in the regulation of bone remodeling and in the interactions between bone remodeling, architecture and bone tissue properties. The most striking changes during aging and osteoporosis take place in cancello

  14. Alveolar bone grafting with simultaneous cleft lip rhinoplasty.

    Science.gov (United States)

    Kim, Young-Eun; Han, Jihyeon; Baek, Rong-Min; Kim, Baek-Kyu

    2016-11-01

    Optimal timing for cleft lip rhinoplasty is controversial. Definitive rhinoplasty is deferred until facial skeletal growth is completed. Intermediate rhinoplasty is performed after stabilization of the grafted alveolar bone, because the grafted bone tends to be absorbed over several months postoperatively, distorting the nasal profile. Here, we report our experience with simultaneous rhinoplasty during alveolar bone grafting for indicated patients, describe our surgical technique that ensures long-term bone graft survival, and report graft take rates and nasal profile changes. This retrospective chart review included a total of 54 patients; 44 underwent alveolar bone grafting only, and 10 underwent simultaneous cleft lip rhinoplasty. All surgeries were conducted with a judicious mucosal incision for tensionless wound closure. Bone graft take was evaluated with dental radiographs by the Bergland classification. Further, nasal aesthetic outcome was evaluated with medical photographs, based on nostril height and width and alar base width. In total, 96.3% of clefts showed graft success with Type I (66.7%) or Type II (27.8%) classifications; only 3.7% of clefts showed unfavorable results classified as Type III, and no clefts showed Type IV failure. The nasal shape was flatter with a decreased nostril height and increased nostril width after alveolar bone grafting, while nostril height was increased and nostril width was decreased in patients who underwent simultaneous rhinoplasty. With surgical techniques ensuring alveolar bone graft survival, simultaneous cleft lip rhinoplasty can result in nasal aesthetic improvement for patients with severe nasal deformities, decreasing the number of operations. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Parallel mechanisms suppress cochlear bone remodeling to protect hearing.

    Science.gov (United States)

    Jáuregui, Emmanuel J; Akil, Omar; Acevedo, Claire; Hall-Glenn, Faith; Tsai, Betty S; Bale, Hrishikesh A; Liebenberg, Ellen; Humphrey, Mary Beth; Ritchie, Robert O; Lustig, Lawrence R; Alliston, Tamara

    2016-08-01

    Bone remodeling, a combination of bone resorption and formation, requires precise regulation of cellular and molecular signaling to maintain proper bone quality. Whereas osteoblasts deposit and osteoclasts resorb bone matrix, osteocytes both dynamically resorb and replace perilacunar bone matrix. Osteocytes secrete proteases like matrix metalloproteinase-13 (MMP13) to maintain the material quality of bone matrix through perilacunar remodeling (PLR). Deregulated bone remodeling impairs bone quality and can compromise hearing since the auditory transduction mechanism is within bone. Understanding the mechanisms regulating cochlear bone provides unique ways to assess bone quality independent of other aspects that contribute to bone mechanical behavior. Cochlear bone is singular in its regulation of remodeling by expressing high levels of osteoprotegerin. Since cochlear bone expresses a key PLR enzyme, MMP13, we examined whether cochlear bone relies on, or is protected from, osteocyte-mediated PLR to maintain hearing and bone quality using a mouse model lacking MMP13 (MMP13(-/-)). We investigated the canalicular network, collagen organization, lacunar volume via micro-computed tomography, and dynamic histomorphometry. Despite finding defects in these hallmarks of PLR in MMP13(-/-) long bones, cochlear bone revealed no differences in these markers, nor hearing loss as measured by auditory brainstem response (ABR) or distortion product oto-acoustic emissions (DPOAEs), between wild type and MMP13(-/-) mice. Dynamic histomorphometry revealed abundant PLR by tibial osteocytes, but near absence in cochlear bone. Cochlear suppression of PLR corresponds to repression of several key PLR genes in the cochlea relative to long bones. These data suggest that cochlear bone uniquely maintains bone quality and hearing independent of MMP13-mediated osteocytic PLR. Furthermore, the cochlea employs parallel mechanisms to inhibit remodeling by osteoclasts and osteoblasts, and by

  16. Dental implants placed on bone subjected to vertical alveolar distraction show the same performance as those placed on primitive bone

    OpenAIRE

    Pérez Sayáns, Mario; León Camacho, María De Los Ángeles; Somoza Martín, José Manuel; Fernández González, Beatriz; Blanes-Vázquez-Gundín, Silvia; Gándara Rey, José Manuel; García García, Abel

    2013-01-01

    Introduction: Vertical osteogenic alveolar distraction (VOAD) allows for the augmentation of the alveolar ridge for the placement of dental implants in atrophic alveolar ridges. The goal of this paper is to assess long-term peri-implant bone resorption in implants placed on bones subjected to VOAD, comparing it with a group of patients who had implants placed directly on the alveolar bone without previous bone regeneration. Material and Methods: We conducted a follow-up study on 32 patients w...

  17. The behavior of adaptive bone-remodeling simulation models

    NARCIS (Netherlands)

    H.H. Weinans (Harrie); R. Huiskes (Rik); H.J. Grootenboer

    1992-01-01

    textabstractThe process of adaptive bone remodeling can be described mathematically and simulated in a computer model, integrated with the finite element method. In the model discussed here, cortical and trabecular bone are described as continuous materials with variable density. The remodeling rule

  18. New regenerative treatment for tooth and periodontal bone defect associated with posttraumatic alveolar bone crush fracture.

    Science.gov (United States)

    Kiyokawa, Kensuke; Kiyokawa, Munekatsu; Takagi, Mikako; Rikimaru, Hideaki; Fukaya, Takuji

    2009-05-01

    We developed a new regenerative treatment of tooth and periodontal defect and tooth dislocation associated with posttraumatic alveolar bone crush fracture in the region of the maxillary anterior teeth. Using this method, dislocated teeth are first extracted and crushed alveolar bone is debrided. The dislocated teeth are then reimplanted, and cancellous iliac bone (bone marrow) is grafted to the area surrounding the teeth to regenerate periodontal bone. Tooth reimplantation was completely successful in 2 cases, and periodontal bone regenerated to a sufficient height with the iliac bone graft. Compared with the general method of treatment with a prosthesis (bridge), when using this method to treat cases such as these, there is no sacrifice of healthy teeth adjacent to the defect, and sufficient esthetic and functional recovery is possible. It is thought that this method could be applied as a new treatment of alveolar bone fracture in the future.

  19. Multiscale Bone Remodelling with Spatial P Systems

    CERN Document Server

    Cacciagrano, Diletta; Merelli, Emanuela; Tesei, Luca; 10.4204/EPTCS.40.6

    2010-01-01

    Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as ...

  20. Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Gulshan B., E-mail: gbsharma@ucalgary.ca [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States); University of Calgary, Schulich School of Engineering, Department of Mechanical and Manufacturing Engineering, Calgary, Alberta T2N 1N4 (Canada); Robertson, Douglas D., E-mail: douglas.d.robertson@emory.edu [Emory University, Department of Radiology and Imaging Sciences, Spine and Orthopaedic Center, Atlanta, Georgia 30329 (United States); University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213 (United States)

    2013-07-01

    Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respond over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula’s material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element’s remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater than

  1. Does Orthodontic Treatment Affect the Alveolar Bone Density?

    Science.gov (United States)

    Yu, Jian-Hong; Huang, Heng-Li; Liu, Chien-Feng; Wu, Jay; Li, Yu-Fen; Tsai, Ming-Tzu; Hsu, Jui-Ting

    2016-03-01

    Few studies involving human participants have been conducted to investigate the effect of orthodontic treatment on alveolar bone density around the teeth. Our previous study revealed that patients who received 6 months of active orthodontic treatment exhibited an ∼24% decrease in alveolar bone density around the teeth. However, after an extensive retention period following orthodontic treatment, whether the bone density around the teeth can recover to its original state from before the treatment remains unclear, thus warranting further investigation.The purpose of this study was to assess the bone density changes around the teeth before, during, and after orthodontic treatment.Dental cone-beam computed tomography (CBCT) was used to measure the changes in bone density around 6 teeth in the anterior maxilla (maxilla central incisors, lateral incisors, and canines) of 8 patients before and after orthodontic treatment. Each patient underwent 3 dental CBCT scans: before treatment (T0); at the end of 7 months of active orthodontic treatment (T1); after several months (20-22 months) of retention (T2). The Friedman test was applied to evaluate the changes in the alveolar bone density around the teeth according to the 3 dental CBCT scans.From T0 to T1, a significant reduction in bone density was observed around the teeth (23.36 ± 10.33%); by contrast, a significant increase was observed from T1 to T2 (31.81 ± 23.80%). From the perspective of the overall orthodontic treatment, comparing the T0 and T2 scans revealed that the bone density around the teeth was relatively constant (a reduction of only 0.75 ± 19.85%). The results of the statistical test also confirmed that the difference in bone density between T0 and T2 was nonsignificant.During orthodontic tooth movement, the alveolar bone density around the teeth was reduced. However, after a period of bone recovery, the reduced bone density recovered to its previous state from before the orthodontic treatment

  2. Estrogen effects on interleukin-1 expression in alveolar bone remodeling of osteoporotic rats%雌激素干预骨质疏松大鼠牙槽骨改建过程中白细胞介素1的表达

    Institute of Scientific and Technical Information of China (English)

    王袖和; 王长庆; 朱玉平; 张晓东

    2013-01-01

    BACKGROUND:Currently rats are the most frequently used animal for the models of osteoporosis and ovariectomized rat models have been widely applied due to ovariectomized female rats are similar to human body in bone mineral density changes and response after estrogen administration. OBJECTIVE:To establish rat models of osteoporotic tooth extraction wound healing, and to investigate the effect of estrogen on the interleukin-1 expression and distribution in the remodeling of osteoporotic alveolar bone. METHODS:Sixty-five purebred female rats, 3 months old, were randomly divided into two groups:osteoporosis model group (n=40;ovariectomy under general anesthesia) and sham operation group (n=25;fat tissue around ovary was removed). After 8-week feeding, osteoporosis models were established and the left upper molar was pul ed out under general anesthesia. Histomorphomeric parameters test was performed on the jaw bone. In osteoporosis model group, 15 rats were randomly selected to give subcutaneous injection of estradiol benzoate, as the estrogen treatment group. Immunohistochemical method was applied to observe the interleukin-1 expression in the remodeling of osteoporotic alveolar bone. RESULTS AND CONCLUSION:After ovariotomy, the amount of trabecula decreased and the medul ary cavity of the bone became larger, the jaw bone intensity decreased. After administration of estrogen, the positive expression of interleukin-1 was reduced as compared with osteoporosis model group. Experimental findings indicate that, osteoporosis can be detected in Sprague-Dawley female rats aged 3 months at 8 weeks after ovariotomy, and administration of estrogen can obviously decrease interleukin-1 positive expression in the remodeling of osteoporotic alveolar bone.%背景:目前大鼠是骨质疏松研究中使用最多的模型动物,其中大鼠去卵巢动物模型应用最广泛,雌性大鼠在卵巢切除后,其骨质变化和给予雌激素后的反应与人相似。

  3. Premature loss of bone remodeling compartment canopies is associated with deficient bone formation

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Søe, Kent;

    2011-01-01

    A remarkable property of bone remodeling is that osteoblasts form bone matrix exactly where and when osteoclasts have removed it. The bone remodeling compartment (BRC) canopies that cover bone surfaces undergoing remodeling, were proposed to be critical players in this mechanism. Here, we provide...... support to this hypothesis by analyzing the changes in prevalence of BRC canopies during the progress of the remodeling cycle in a cohort of healthy individuals and in patients with endogenous Cushing's syndrome (CS), and by relating these changes in prevalence with the extent of bone forming surfaces...

  4. Skeletal Site-specific Effects of Zoledronate on in vivo Bone Remodeling and in vitro BMSCs Osteogenic Activity

    Science.gov (United States)

    Gong, Xue; Yu, Wanlu; Zhao, Hang; Su, Jiansheng; Sheng, Qing

    2017-01-01

    Bisphosphonate-related osteonecrosis of the jaw (BRONJ) has been associated with long-term oral or intravenous administration of nitrogen-containing bisphosphonates (BPs). However, the pathogenesis of BRONJ remains unknown, and definitively effective treatment has not yet been established. Bisphosphonate-related osteonecrosis (BRON) tends to occur in maxillofacial bones. Why this occurs is still unclear. Here we show that zoledronate (Zol) treatment suppresses alveolar bone remodeling after tooth typical clinical and radiographic hallmarks of the human BRONJ, whereas enhances peripheral bone quantity in bone remodeling following injury in the same individuals, shown as increased cortical bone thickness, increased trabecular bone formation and accelerated bone defect repair. We find that the RANKL/OPG ratio and Wnt-3a expression are suppressed at the extracted alveolar sites in Zol-treated rats compared with those at the injured sites of peripheral bones. We also show that Zol-treated bone marrow stromal cell (BMSCs) derived from jaw and peripheral bones exhibit differences in cell proliferation, alkaline phosphatase (ALP) activity, expression of osteogenic and chondrogenic related marker genes, and in vivo bone formation capacity. Hopefully, this study will help us better understand the pathogenesis of BRONJ, and deepen the theoretical research. PMID:28139685

  5. 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

  6. Correlation between absence of bone remodeling compartment canopies, reversal phase arrest, and deficient bone formation in post-menopausal osteoporosis

    DEFF Research Database (Denmark)

    Levin Andersen, Thomas; Hauge, Ellen M; Rolighed, Lars;

    2014-01-01

    Bone remodeling compartments (BRCs) were recently recognized to be present in patients with primary hyperparathyroidism and critical for bone reconstruction in multiple myeloma and endogenous Cushing's syndrome. The BRCs are outlined by a cellular canopy separating the bone remodeling events...

  7. Novel bioceramic-reinforced hydrogel for alveolar bone regeneration.

    Science.gov (United States)

    Iviglia, Giorgio; Cassinelli, Clara; Torre, Elisa; Baino, Francesco; Morra, Marco; Vitale-Brovarone, Chiara

    2016-10-15

    The osseointegration of dental implants and their consequent long-term success is guaranteed by the presence, in the extraction site, of healthy and sufficient alveolar bone. Bone deficiencies may be the result of extraction traumas, periodontal disease and infection. In these cases, placement of titanium implants is contraindicated until a vertical bone augmentation is obtained. This goal is achieved using bone graft materials, which should simulate extracellular matrix (ECM), in order to promote osteoblast proliferation and fill the void, maintaining the space without collapsing until the new bone is formed. In this work, we design, develop and characterize a novel, moldable chitosan-pectin hydrogel reinforced by biphasic calcium phosphate particles with size in the range of 100-300μm. The polysaccharide nature of the hydrogel mimics the ECM of natural bone, and the ceramic particles promote high osteoblast proliferation, assessed by Scanning Electron Microscopy analysis. Swelling properties allow significant adsorption of water solution (up to 200% of solution content) so that the bone defect space can be filled by the material in an in vivo scenario. The incorporation of ceramic particles makes the material stable at different pH and increases the compressive elastic modulus, toughness and ultimate tensile strength. Furthermore, cell studies with SAOS-2 human osteoblastic cell line show high cell proliferation and adhesion already after 72h, and the presence of ceramic particles increases the expression of alkaline phosphatase activity after 1week. These results suggest a great potential of the developed moldable biomaterials for the regeneration of the alveolar bone. The positive fate of a surgical procedure involving the insertion of a titanium screw still depends on the quality and quantity of alveolar bone which is present in the extraction site. Available materials are basically hard scaffold materials with un-predictable behavior in different condition

  8. 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.

  9. 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...

  10. Alveolar bone measurement precision for phosphor-plate images

    Science.gov (United States)

    HILDEBOLT, CHARLES F.; COUTURE, REX; GARCIA, NATHALIA M.; DIXON, DEBRA; SHANNON, WILLIAM DOUGLAS; LANGENWALTER, ERIC; CIVITELLI, ROBERTO

    2009-01-01

    Objectives To demonstrate methods for determining measurement precision and to determine the precision of alveolar-bone measurements made with a vacuum-coupled, positioning device and phosphor-plate images. Study design Subjects were rigidly attached to the x-ray tube by means of a vacuum coupling device and custom, cross-arch, bite plates. Original and repeat radiographs (taken within minutes of each other) were obtained of the mandibular posterior teeth of 51 subjects, and cementoenamel-junction-alveolar-crest (CEJ-AC) distances were measured on both sets of images. In addition, x-ray-transmission (radiodensity) and alveolar-crest-height differences were determined by subtracting one image from the other. Image subtractions and measurements were performed twice. Based on duplicate measurements, the root-mean-square standard deviation (precision) and least-significant change (LSC) were calculated. LSC is the magnitude of change in a measurement needed to indicate that a true biological change has occurred. Results The LSCs were 4% for x-ray transmission, 0.49 mm for CEJ-AC distance, and 0.06 mm for crest-height 0.06 mm. Conclusion The LSCs for our CEJ-AC and x-ray transmission measurements are similar to what has been reported. The LSC for alveolar-crest height (determined with image subtraction) was less than 0.1 mm. Compared with findings from previous studies, this represents a highly precise measurement of alveolar crest height. The methods demonstrated for calculating LSC can be used by investigators to determine how large changes in radiographic measurements need to be before the changes can be considered (with 95% confidence) true biological changes and not noise (that is, equipment/observer error). PMID:19716499

  11. Hydroxyapatite-coated uncemented hip stems and bone remodeling

    NARCIS (Netherlands)

    Wal, B.C.H. van der

    2010-01-01

    In this thesis the clinical results, the periprosthetic bone remodeling and histological analysis of an anatomical designed proximally hydroxyapatite-coated hip prosthesis were investigated to answer several research questions. In our first prospective study the characteristics of the bone remodelin

  12. De novo alveolar bone formation adjacent to endosseous implants.

    Science.gov (United States)

    Berglundh, Tord; Abrahamsson, Ingemar; Lang, Niklaus P; Lindhe, Jan

    2003-06-01

    To describe a model for the investigation of different phases of wound healing that are involved in the process resulting in osseointegration. The implants used for the study of early healing had a geometry that corresponded to that of a solid screw implant with an SLA surface configuration. A circumferential trough had been prepared within the thread region (intra-osseous portion) that established a geometrically well-defined wound compartment. Twenty Labrador dogs received 160 experimental devices totally to allow the evaluation of healing between 2 h and 12 weeks. Both ground sections and decalcified sections were prepared from different implant sites. The experimental chamber used appeared to be conducive for the study of early phases of bone formation. The ground sections provided an overview of the various phases of soft and hard tissue formation, while the decalcified, thin sections enabled a more detailed study of events involved in bone tissue modeling and remodeling. The initially empty wound chamber became occupied with a coagulum and a granulation tissue that was replaced by a provisional matrix. The process of bone formation started already during the first week. The newly formed bone present at the lateral border of the cut bony bed appeared to be continuous with the parent bone, but woven bone was also found on the SLA surface at a distance from the parent bone. This primary bone that included trabeculae of woven bone was replaced by parallel-fibered and/or lamellar bone and marrow. Between 1 and 2 weeks, the bone tissue immediately lateral to the pitch region, responsible for primary mechanical stability of the device, became resorbed and replaced with newly formed viable bone. Despite this temporary loss of hard tissue contact, the implants remained clinically stable at all times. Osseointegration represents a dynamic process both during its establishment and its maintenance. In the establishment phase, there is a delicate interplay between bone

  13. Role of Cannabinoids in the Regulation of Bone Remodelling

    Directory of Open Access Journals (Sweden)

    Aymen I Idris

    2012-11-01

    Full Text Available The endocannabinoid system plays a key role in regulating a variety of physiological processes such as appetite control and energy balance, pain perception, and immune responses. Recent studies have implicated the endocannabinoid system in the regulation of bone cell activity and bone remodelling. These studies showed that endogenous cannabinoid ligands, cannabinoid receptors and the enzymes responsible for ligand synthesis and breakdown all play important roles in bone mass and in the regulation of bone disease. These findings suggest that the endocannabinoid pathway could be of value as a therapeutic target for the prevention and treatment of bone diseases. Here, we review the role of the skeletal endocannabinoid system in the regulation of bone remodelling in health and disease.

  14. Plasma cell gingivitis with severe alveolar bone loss.

    Science.gov (United States)

    Kumar, Vivek; Tripathi, Amitandra Kumar; Saimbi, Charanjit Singh; Sinha, Jolly

    2015-01-16

    Plasma cell gingivitis is a rare benign condition of the gingiva characterised by sharply demarcated erythaematous and oedematous gingiva often extending up to the muco gingival junction. It is considered a hypersensitive reaction. It presents clinically as a diffuse, erythaematous and papillary lesion of the gingiva, which frequently bleeds, with minimal trauma. This paper presents a case of a 42-year-old man who was diagnosed with plasma cell gingivitis, based on the presence of plasma cells in histological sections, and severe alveolar bone loss at the affected site, which was managed by surgical intervention.

  15. Changes in alveolar bone support induced by the Herbst appliance: a tomographic evaluation

    Directory of Open Access Journals (Sweden)

    João Paulo Schwartz

    2016-04-01

    Full Text Available ABSTRACT Objective: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. Methods: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years, Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0 and after Herbst treatment (T1. Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B, lingual (L and total (T bone thicknesses were assessed at crestal (1, midroot (2 and apical (3 levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. Results: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. Conclusions: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance.

  16. The role of microRNAs in bone remodeling

    Institute of Scientific and Technical Information of China (English)

    Dian Jing; Jin Hao; Yu Shen; Ge Tang; Mei-Le Li; Shi-Hu Huang; Zhi-He Zhao

    2015-01-01

    Bone remodeling is balanced by bone formation and bone resorption as well as by alterations in the quantities and functions of seed cells, leading to either the maintenance or deterioration of bone status. The existing evidence indicates that microRNAs (miRNAs), known as a family of short non-coding RNAs, are the key post-transcriptional repressors of gene expression, and growing numbers of novel miRNAs have been verified to play vital roles in the regulation of osteogenesis, osteoclastogenesis, and adipogenesis, revealing how they interact with signaling molecules to control these processes. This review summarizes the current knowledge of the roles of miRNAs in regulating bone remodeling as well as novel applications for miRNAs in biomaterials for therapeutic purposes.

  17. A Computational Model for Simulating Spaceflight Induced Bone Remodeling

    Science.gov (United States)

    Pennline, James A.; Mulugeta, Lealem

    2014-01-01

    An overview of an initial development of a model of bone loss due to skeletal unloading in weight bearing sites is presented. The skeletal site chosen for the initial application of the model is the femoral neck region because hip fractures can be debilitating to the overall performance health of astronauts. The paper begins with the motivation for developing such a model of the time course of change in bone in order to understand the mechanism of bone demineralization experienced by astronauts in microgravity, to quantify the health risk, and to establish countermeasures. Following this, a general description of a mathematical formulation of the process of bone remodeling is discussed. Equations governing the rate of change of mineralized bone volume fraction and active osteoclast and osteoblast are illustrated. Some of the physiology of bone remodeling, the theory of how imbalance in remodeling can cause bone loss, and how the model attempts to capture this is discussed. The results of a preliminary validation analysis that was carried out are presented. The analysis compares a set of simulation results against bone loss data from control subjects who participated in two different bed rest studies. Finally, the paper concludes with outlining the current limitations and caveats of the model, and planned future work to enhance the state of the model.

  18. Localized tissue mineralization regulated by bone remodelling: A computational approach

    Science.gov (United States)

    Decco, Oscar; Adams, George; Cook, Richard B.; García Aznar, José Manuel

    2017-01-01

    Bone is a living tissue whose main mechanical function is to provide stiffness, strength and protection to the body. Both stiffness and strength depend on the mineralization of the organic matrix, which is constantly being remodelled by the coordinated action of the bone multicellular units (BMUs). Due to the dynamics of both remodelling and mineralization, each sample of bone is composed of structural units (osteons in cortical and packets in cancellous bone) created at different times, therefore presenting different levels of mineral content. In this work, a computational model is used to understand the feedback between the remodelling and the mineralization processes under different load conditions and bone porosities. This model considers that osteoclasts primarily resorb those parts of bone closer to the surface, which are younger and less mineralized than older inner ones. Under equilibrium loads, results show that bone volumes with both the highest and the lowest levels of porosity (cancellous and cortical respectively) tend to develop higher levels of mineral content compared to volumes with intermediate porosity, thus presenting higher material densities. In good agreement with recent experimental measurements, a boomerang-like pattern emerges when plotting apparent density at the tissue level versus material density at the bone material level. Overload and disuse states are studied too, resulting in a translation of the apparent–material density curve. Numerical results are discussed pointing to potential clinical applications. PMID:28306746

  19. Microtomography of the human tooth-alveolar bone complex

    Science.gov (United States)

    Dalstra, Michel; Cattaneo, Paolo M.; Beckmann, Felix; Sakima, Maurício T.; Lemor, Carsten; Laursen, Morten G.; Melsen, Birte

    2006-08-01

    In this study the structure of the adult human dentoalveolar process is examined using conventional and synchrotron radiation-based microtomography (SRμCT). Mandibular and maxillary segments containing two to five adjacent teeth were harvested at autopsy from 49 adult donors. These segments were embedded in blocks of methylmetacrylate and scanned using a conventional table-top μCT-scanner at a pixel size and slice thickness of 35 μm. A few segments were also scanned at a synchrotron facility at an initial pixel size of 16.4 μm, which was binned by a factor 2 to result in an effective voxel size of almost 32.8 μm. The three-dimensional reconstructions revealed how intricately the teeth are supported by the alveolar bone. Furthermore, this support is highly inhomogeneous with respect to the buccal, mesial, lingual and distal quadrants. Reflecting their various degrees of mineralization, tissues like bone, dentine, enamel and cementum, could well be identified, especially in the scans made with SRμCT. Despite comparable voxel sizes, the reconstructed data-sets obtained with conventional μCT were less detailed and somewhat fuzzy in appearance compared to the data-sets of SRμCT. However, for quantification of macroscopical features like the thickness of the alveolar wall or the presence of dehiscences/fenestrations this seemed sufficient.

  20. An "S-shaped" relationship between smoking duration and alveolar bone loss : generating a hypothesis

    NARCIS (Netherlands)

    Schuller, A A; Holst, D

    2001-01-01

    BACKGROUND: A number of epidemiological studies have shown that smoking is a risk factor for periodontal disease. Little is known about the relationship between smoking duration and alveolar bone loss. The purpose of this research was to describe the prevalence of alveolar bone loss according to smo

  1. Morbidity of chin bone transplants used for reconstructing alveolar defects in cleft patients

    NARCIS (Netherlands)

    Booij, A; Raghoebar, GM; Jansma, J; Kalk, WWI; Vissink, A

    2005-01-01

    Objective: The aim of this study was to evaluate the objective and subjective morbidity of symphyseal chin bone harvesting used for reconstruction of alveolar defects in young cleft patients. Design: All patients who had undergone chin bone harvesting for alveolar cleft reconstruction in the period

  2. Morbidity of chin bone transplants used for reconstructing alveolar defects in cleft patients

    NARCIS (Netherlands)

    Booij, A; Raghoebar, GM; Jansma, J; Kalk, WWI; Vissink, A

    Objective: The aim of this study was to evaluate the objective and subjective morbidity of symphyseal chin bone harvesting used for reconstruction of alveolar defects in young cleft patients. Design: All patients who had undergone chin bone harvesting for alveolar cleft reconstruction in the period

  3. Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate

    NARCIS (Netherlands)

    Guo, J.; Li, C.; Zhang, Q.; Wu, G.; Deacon, S.A.; Chen, J.; Hu, H.; Zou, S.; Ye, Q.

    2011-01-01

    BACKGROUND: Secondary alveolar bone grafting has been widely used to reconstruct alveolar cleft. However, there is still some controversy. OBJECTIVES: To compare the effectiveness and safety of different secondary bone grafting methods. SEARCH STRATEGY: The final electronic and handsearches were car

  4. Alveolar Ridge Preservation Using Xenogeneic Collagen Matrix and Bone Allograft

    Directory of Open Access Journals (Sweden)

    Andreas O. Parashis

    2014-01-01

    Full Text Available Alveolar ridge preservation (ARP has been shown to prevent postextraction bone loss. The aim of this report is to highlight the clinical, radiographic, and histological outcomes following use of a bilayer xenogeneic collagen matrix (XCM in combination with freeze-dried bone allograft (FDBA for ARP. Nine patients were treated after extraction of 18 teeth. Following minimal flap elevation and atraumatic extraction, sockets were filled with FDBA. The XCM was adapted to cover the defect and 2-3 mm of adjacent bone and flaps were repositioned. Healing was uneventful in all cases, the XCM remained in place, and any matrix exposure was devoid of further complications. Exposed matrix portions were slowly vascularized and replaced by mature keratinized tissue within 2-3 months. Radiographic and clinical assessment indicated adequate volume of bone for implant placement, with all planned implants placed in acceptable positions. When fixed partial dentures were placed, restorations fulfilled aesthetic demands without requiring further augmentation procedures. Histological and immunohistochemical analysis from 9 sites (4 patients indicated normal mucosa with complete incorporation of the matrix and absence of inflammatory response. The XCM + FDBA combination resulted in minimal complications and desirable soft and hard tissue therapeutic outcomes, suggesting the feasibility of this approach for ARP.

  5. Transcriptional regulation of bone and joint remodeling by NFAT

    OpenAIRE

    2010-01-01

    Osteoporosis and arthritis are highly prevalent diseases and a significant cause of morbidity and mortality worldwide. These diseases result from aberrant tissue remodeling leading to weak, fracture-prone bones or painful, dysfunctional joints. The nuclear factor of activated T cells (NFAT) transcription factor family controls diverse biologic processes in vertebrates. Here, we review the scientific evidence that links NFAT-regulated gene transcription to bone and joint pathology. A particula...

  6. Bone remodeling around cementless tantalum cups

    NARCIS (Netherlands)

    Grillo, J. -C.; Flecher, X.; Bouvenot, J.; Argenson, J. -N.

    2008-01-01

    Purpose of the study.-Most studies have reported a significant decrease in periacetabular bone stock one year after implantation of a cementless cup. The purpose of this work was to study the bone-implant interface of the tantalum cup using plain X-rays and dual-energy X-ray absorptiometry (DEXA). M

  7. Bone remodelling around a cementless glenoid component

    NARCIS (Netherlands)

    Suarez, D.R.; Weinans, H.; Van Keulen, F.

    2012-01-01

    Post-operative change in the mechanical loading of bone may trigger its (mechanically induced) adaptation and hamper the mechanical stability of prostheses. This is especially important in cementless components, where the final fixation is achieved by the bone itself. The aim of this study is,

  8. Bone remodelling around a cementless glenoid component

    NARCIS (Netherlands)

    D.R. Suárez (Daniel); H.H. Weinans (Harrie); F. van Keulen (Fred)

    2012-01-01

    textabstractPost-operative change in the mechanical loading of bone may trigger its (mechanically induced) adaptation and hamper the mechanical stability of prostheses. This is especially important in cementless components, where the final fixation is achieved by the bone itself. The aim of this

  9. The Digital Astronaut Project Bone Remodeling Model

    Science.gov (United States)

    Pennline, James A.; Mulugeta, Lealem; Lewandowski, Beth E.; Thompson, William K.; Sibonga, Jean D.

    2014-01-01

    Under the conditions of microgravity, astronauts lose bone mass at a rate of 1% to 2% a month, particularly in the lower extremities such as the proximal femur: (1) The most commonly used countermeasure against bone loss has been prescribed exercise, (2) However, current exercise countermeasures do not completely eliminate bone loss in long duration, 4 to 6 months, spaceflight, (3,4) leaving the astronaut susceptible to early onset osteoporosis and a greater risk of fracture later in their lives. The introduction of the Advanced Resistive Exercise Device, coupled with improved nutrition, has further minimized the 4 to 6 month bone loss. But further work is needed to implement optimal exercise prescriptions, and (5) In this light, NASA's Digital Astronaut Project (DAP) is working with NASA physiologists to implement well-validated computational models that can help understand the mechanisms of bone demineralization in microgravity, and enhance exercise countermeasure development.

  10. Bone remodeling induced by dental implants of functionally graded materials.

    Science.gov (United States)

    Lin, Daniel; Li, Qing; Li, Wei; Swain, Michael

    2010-02-01

    Functionally graded material (FGM) had been developed as a potential implant material to replace titanium for its improved capability of initial osseointegration. The idea behind FGM dental implant is that its properties can be tailored in accordance with the biomechanical needs at different regions adapting to its hosting bony tissues, therefore creating an improved overall integration and stability in the entire restoration. However, there have been very few reports available so far on predicting bone remodeling induced by FGM dental implants. This article aims to evaluate bone remodeling when replacing the titanium with a hydroxyapatite/collagen (HAP/Col) FGM model. A finite element model was constructed in the buccal-lingual section of a dental implant-bone structure generated from in vivo CT scan images. The remodeling simulation was performed over a 4 year healing period. Comparisons were made between the titanium implant and various FGM implants of this model. The FGM implants showed an improved bone remodeling outcome. The study is expected to provide a basis for future development of FGM implants.

  11. 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

  12. Skoog Primary Periosteoplasty versus Secondary Alveolar Bone Grafting in Unilateral Cleft Lip and Alveolus: Long-Term Effects on Alveolar Bone Formation and Maxillary Growth.

    Science.gov (United States)

    Jabbari, Fatima; Hakelius, Malin M; Thor, Andreas L I; Reiser, Erika A; Skoog, Valdemar T; Nowinski, Daniel J

    2017-01-01

    Clefts involving the alveolus are treated using one of two strategies: primary periosteoplasty at the time of lip repair or secondary alveolar bone grafting at mixed dentition. Most teams favor secondary alveolar bone grafting because of its high success rate, and concerns have been raised that primary periosteoplasty may interfere with maxillary growth. However, primary periosteoplasty may obviate the need for future bone grafting and is still practiced in some centers. Few studies compare the long-term outcomes of these two strategies. Fifty-seven consecutive patients born with unilateral cleft lip and alveolus were studied retrospectively. All patients underwent primary lip repair using Skoog's method; 28 patients underwent primary periosteoplasty at the time of lip repair and the remaining 29 underwent secondary alveolar bone grafting at mixed dentition. Occlusal radiographs obtained at ages 10 and 16 years were analyzed for alveolar bone height. Cephalometric analysis assessed growth at ages 5, 10, and 18 years. Seventeen of 28 patients treated using primary periosteoplasty required later secondary bone grafting, and the bone height at age 16 years was lower in the primary periosteoplasty group (p < 0.0001). There was a more pronounced decrease in maxillary protrusion from ages 5 to 10 years in the primary periosteoplasty group (p < 0.03). However, at age 18 there was no significant difference in maxillary growth between the two groups. Primary periosteoplasty did not seem to inhibit long-term maxillary growth but was ineffective as a method of reconstructing the alveolar cleft. Therapeutic, III.

  13. Oral administration of 5-hydroxytryptophan aggravated periodontitis-induced alveolar bone loss in rats.

    Science.gov (United States)

    Li, Xianxian; Wu, Xiangnan; Ma, Yuanyuan; Hao, Zhichao; Chen, Shenyuan; Fu, Taozi; Chen, Helin; Wang, Hang

    2015-05-01

    5-Hydroxytryptophan (5-HTP) is the precursor of serotonin and 5-HTP has been widely used as a dietary supplement to raise serotonin level. Serotonin has recently been discovered to be a novel and important player in bone metabolism. As peripheral serotonin negatively regulates bone, the regular take of 5-HTP may affect the alveolar bone metabolism and therefore influence the alveolar bone loss induced by periodontitis. The aim of this study was to investigate the effect of 5-HTP on alveolar bone destruction in periodontitis. Male Sprague-Dawley rats were randomly divided into the following four groups: (1) the control group (without ligature); (2) the 5-HTP group (5-HTP at 25 mg/kg/day without ligature); (3) the L group (ligature+saline placebo); and (4) the L+5-HTP group (ligature+5-HTP at 25 mg/kg/day). Serum serotonin levels were determined by ELISA. The alveolar bones were evaluated with micro-computed tomography and histology. Tartrate-resistant acid phosphatase staining was used to assess osteoclastogenesis. The receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG) expression in the periodontium as well as the interleukin-6 positive osteocytes were analysed immunohistochemically. 5-HTP significantly increased serum serotonin levels. In rats with experimental periodontitis, 5-HTP increased alveolar bone resorption and worsened the micro-structural destruction of the alveolar bone. 5-HTP also stimulated osteoclastogenesis and increased RANKL/OPG ratio and the number of IL-6 positive osteocytes. However, 5-HTP treatment alone did not cause alveolar bone loss in healthy rats. The present study showed that 5-HTP aggravated alveolar bone loss, deteriorated alveolar bone micro-structure in the presence of periodontitis, which suggests 5-HTP administration may increase the severity of periodontitis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. 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...

  15. Effects of oestrogen deficiency on the alveolar bone of rats with experimental periodontitis

    OpenAIRE

    Xu, Xin-chen; Chen, Hui; Zhang, Xi; ZHAI, ZAN-JING; Liu, Xu-qiang; ZHENG, XIN-YI; Zhang, Jun; Qin, An; Lu, Er-yi

    2015-01-01

    Periodontitis is an inflammatory disease characterized by loss of connective tissue and alveolar bone, and osteoporosis is a common disease characterized by a systemic impairment of bone mass and microarchitecture. To date, the association between periodontitis and osteoporosis has remained to be fully elucidated. In the present study, an experimental rat model of periodontitis was used to explore the effects of oestrogen deficiency-induced osteoporosis on the maxillary alveolar bone. Forty-f...

  16. Inflammatory and bone remodeling responses to the cytolethal distending toxins.

    Science.gov (United States)

    Belibasakis, Georgios N; Bostanci, Nagihan

    2014-04-04

    The cytolethal distending toxins (CDTs) are a family of exotoxins produced by a wide range of Gram-negative bacteria. They are known for causing genotoxic stress to the cell, resulting in growth arrest and eventually apoptotic cell death. Nevertheless, there is evidence that CDTs can also perturb the innate immune responses, by regulating inflammatory cytokine production and molecular mediators of bone remodeling in various cell types. These cellular and molecular events may in turn have an effect in enhancing local inflammation in diseases where CDT-producing bacteria are involved, such as Aggregatibacter actinomycetemcomitans, Haemophilus ducreyi, Campylobacter jejuni and Helicobacter hepaticus. One special example is the induction of pathological bone destruction in periodontitis. The opportunistic oral pathogen Aggregatibatcer actinoycemetemcomitans, which is involved in the aggressive form of the disease, can regulate the molecular mechanisms of bone remodeling in a manner that favors bone resorption, with the potential involvement of its CDT. The present review provides an overview of all known to-date inflammatory or bone remodeling responses of CDTs produced by various bacterial species, and discusses their potential contribution to the pathogenesis of the associated diseases.

  17. Inflammatory and Bone Remodeling Responses to the Cytolethal Distending Toxins

    Directory of Open Access Journals (Sweden)

    Georgios N. Belibasakis

    2014-04-01

    Full Text Available The cytolethal distending toxins (CDTs are a family of exotoxins produced by a wide range of Gram-negative bacteria. They are known for causing genotoxic stress to the cell, resulting in growth arrest and eventually apoptotic cell death. Nevertheless, there is evidence that CDTs can also perturb the innate immune responses, by regulating inflammatory cytokine production and molecular mediators of bone remodeling in various cell types. These cellular and molecular events may in turn have an effect in enhancing local inflammation in diseases where CDT-producing bacteria are involved, such as Aggregatibacter actinomycetemcomitans, Haemophilus ducreyi, Campylobacter jejuni and Helicobacter hepaticus. One special example is the induction of pathological bone destruction in periodontitis. The opportunistic oral pathogen Aggregatibatcer actinoycemetemcomitans, which is involved in the aggressive form of the disease, can regulate the molecular mechanisms of bone remodeling in a manner that favors bone resorption, with the potential involvement of its CDT. The present review provides an overview of all known to-date inflammatory or bone remodeling responses of CDTs produced by various bacterial species, and discusses their potential contribution to the pathogenesis of the associated diseases.

  18. Bone Replacement Materials and Techniques Used for Achieving Vertical Alveolar Bone Augmentation

    Directory of Open Access Journals (Sweden)

    Zeeshan Sheikh

    2015-05-01

    Full Text Available Alveolar bone augmentation in vertical dimension remains the holy grail of periodontal tissue engineering. Successful dental implant placement for restoration of edentulous sites depends on the quality and quantity of alveolar bone available in all spatial dimensions. There are several surgical techniques used alone or in combination with natural or synthetic graft materials to achieve vertical alveolar bone augmentation. While continuously improving surgical techniques combined with the use of auto- or allografts provide the most predictable clinical outcomes, their success often depends on the status of recipient tissues. The morbidity associated with donor sites for auto-grafts makes these techniques less appealing to both patients and clinicians. New developments in material sciences offer a range of synthetic replacements for natural grafts to address the shortcoming of a second surgical site and relatively high resorption rates. This narrative review focuses on existing techniques, natural tissues and synthetic biomaterials commonly used to achieve vertical bone height gain in order to successfully restore edentulous ridges with implant-supported prostheses.

  19. Identification of molecular markers related to human alveolar bone cells and pathway analysis in diabetic patients.

    Science.gov (United States)

    Sun, X; Ren, Q H; Bai, L; Feng, Q

    2015-10-28

    Alveolar bone osteoblasts are widely used in dental and related research. They are easily affected by systemic diseases such as diabetes. However, the mechanism of diabetes-induced alveolar bone absorption remains unclear. This study systematically explored the changes in human alveolar bone cell-related gene expression and biological pathways, which may facilitate the investigation of its mechanism. Alveolar bone osteoblasts isolated from 5 male diabetics and 5 male healthy adults were cultured. Total RNA was extracted from these cells and subjected to gene microarray analysis. Differentially expressed genes were screened, and a gene interaction network was constructed. An enrichment pathway analysis was simultaneously performed on differentially expressed genes to identify the biological pathways associated with changes in the alveolar bone cells of diabetic humans. In total, we identified 147 mRNAs that were differentially expressed in diabetic alveolar bone cells (than in the normal cells; 91 upregulated and 36 downregulated mRNAs). The constructed co-expression network showed 3 pairs of significantly-expressed genes. High-enrichment pathway analysis identified 8 pathways that were affected by changes in gene expression; three of the significant pathways were related to metabolism (inositol phosphate metabolism, propanoate metabolism, and pyruvate metabolism). Here, we identified a few potential genes and biological pathways for the diagnosis and treatment of alveolar bone cells in diabetic patients.

  20. 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

  1. The potential of mangosteen (Garcinia mangostana peel extract, combined with demineralized freeze-dried bovine bone xenograft, to reduce ridge resorption and alveolar bone regeneration in preserving the tooth extraction socket

    Directory of Open Access Journals (Sweden)

    Utari Kresnoadi

    2017-01-01

    Conclusion: The induction of MPEs and DFBBX is effective in reducing inflammation, lowering osteoclasts, decreasing alveolar bone resorption, and also increasing BMP2 expression and alveolar bone regeneration.

  2. Phase field approaches of bone remodeling based on TIP

    Science.gov (United States)

    Ganghoffer, Jean-François; Rahouadj, Rachid; Boisse, Julien; Forest, Samuel

    2016-01-01

    The process of bone remodeling includes a cycle of repair, renewal, and optimization. This adaptation process, in response to variations in external loads and chemical driving factors, involves three main types of bone cells: osteoclasts, which remove the old pre-existing bone; osteoblasts, which form the new bone in a second phase; osteocytes, which are sensing cells embedded into the bone matrix, trigger the aforementioned sequence of events. The remodeling process involves mineralization of the bone in the diffuse interface separating the marrow, which contains all specialized cells, from the newly formed bone. The main objective advocated in this contribution is the setting up of a modeling and simulation framework relying on the phase field method to capture the evolution of the diffuse interface between the new bone and the marrow at the scale of individual trabeculae. The phase field describes the degree of mineralization of this diffuse interface; it varies continuously between the lower value (no mineral) and unity (fully mineralized phase, e.g. new bone), allowing the consideration of a diffuse moving interface. The modeling framework is the theory of continuous media, for which field equations for the mechanical, chemical, and interfacial phenomena are written, based on the thermodynamics of irreversible processes. Additional models for the cellular activity are formulated to describe the coupling of the cell activity responsible for bone production/resorption to the kinetics of the internal variables. Kinetic equations for the internal variables are obtained from a pseudo-potential of dissipation. The combination of the balance equations for the microforce associated to the phase field and the kinetic equations lead to the Ginzburg-Landau equation satisfied by the phase field with a source term accounting for the dissipative microforce. Simulations illustrating the proposed framework are performed in a one-dimensional situation showing the evolution of

  3. Long-term outcome of secondary alveolar bone grafting in cleft lip and palate patients

    DEFF Research Database (Denmark)

    Meyer, Steffen; Pedersen, Kirsten Mølsted

    2013-01-01

    The objective was to assess the long-term outcome of secondary alveolar bone grafting (SABG) in cleft lip and palate patients and to examine relationships between preoperative and postoperative factors and overall long-term bone graft success. The records of 97 patients with cleft lip and palate......, who had secondary alveolar bone grafting of 123 alveolar clefts, were examined. Interalveolar bone height was assessed radiographically a minimum of 10 years after grafting using a 4-point scale (I-IV), where types I and II were considered a success. After an average follow-up of 16 years after SABG...... to the cleft. No significant differences were found with regard to the other parameters investigated. The timing of secondary alveolar bone grafting is critical with regard to the age of the patient and the stage of eruption of the tooth distal to the cleft....

  4. 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

  5. Presurgical orthodontic decompensation alters alveolar bone condition around mandibular incisors in adults with skeletal Class III malocclusion.

    Science.gov (United States)

    Sun, Boyang; Tang, Jun; Xiao, Ping; Ding, Ying

    2015-01-01

    This study is to use cone beam computed tomography (CBCT) to acquire accurate radiographic images for alveolar bone in lower incisors and the change after presurgical orthodontic treatment. Seventeen patients with skeletal Class III malocclusion, ten normal occlusion subjects, and fifteen patients treated with orthodontic treatment and orthognathic surgery were included. CBCT images were obtained. The labial and lingual inclinations of mandibular incisors, the thickness of alveolar bone, the vertical alveolar height and root length were measured. Alveolar bone thickness at the apex in patients with skeletal Class III malocclusion was thinner than normal subjects. The vertical alveolar bone heights at labial and lingual sides in patients with skeletal Class III malocclusion were both reduced compared with normal subjects, especially at the labial side. There were statistically significant correlations between lower incisor inclination and alveolar bone morphology. After orthodontics, the incisors root apex was closer to the lingual side of alveolar bone. The alveolar bone thickness at apex was not statistically changed. The vertical alveolar bone heights at the labial and lingual sides were both significantly reduced especially the lingual side after presurgical orthodontic treatment. The root length was not significantly changed. In conclusion, the alveolar bone thickness at apex is thinner and the vertical alveolar height is reduced at the labial side. Forward movement of lower incisors during presurgical orthodontic treatment can render the lower incisors root apex closer to the lingual side and the vertical alveolar height is reduced.

  6. Can experimental data in humans verify the finite element-based bone remodeling algorithm?

    DEFF Research Database (Denmark)

    Wong, C.; Gehrchen, P.M.; Kiaer, T.

    2008-01-01

    STUDY DESIGN: A finite element analysis-based bone remodeling study in human was conducted in the lumbar spine operated on with pedicle screws. Bone remodeling results were compared to prospective experimental bone mineral content data of patients operated on with pedicle screws. OBJECTIVE......: The validity of 2 bone remodeling algorithms was evaluated by comparing against prospective bone mineral content measurements. Also, the potential stress shielding effect was examined using the 2 bone remodeling algorithms and the experimental bone mineral data. SUMMARY OF BACKGROUND DATA: In previous studies......, in the human spine, the bone remodeling algorithms have neither been evaluated experimentally nor been examined by comparing to unsystematic experimental data. METHODS: The site-specific and nonsite-specific iterative bone remodeling algorithms were applied to a finite element model of the lumbar spine...

  7. A RETROSPECTIVE STUDY OF BILATERAL ALVEOLAR BONE GRAFTING

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective. To evaluate the treatment results of bilateral alveolar bone grafting (BABG) in patients with bilateral complete clefts of lip and palate.Methods. A retrospective study was performed in 66 bilateral complete cleft lip and palate patients who received the procedure of BABG, among them 15 were primary BABG and 51 were secondary BABG. The patients were further divided into three groups according to age and eruption stage of the canine at the time of surgery. The result of BABG was evaluated on the radiographs. Results. (1)The overall success rate of BABG was 75.0%, with 83.3% and 72.5% for primary and secondary BABG respectively; (2)The marginal bone level was found to be significantly higher in the youngest age group than in the other groups both for primary and secondary BABG; (3)For both primary and secondary BABG, Group C (patients' age more than 16 years) had the least optimal success rate, with 66.7% and 65.4% respectively. Conclusion. Simultaneous primary palate repair and BABG is safe and feasible procedure for treating unoperated bilateral complete cleft lip and cleft palate patients. For both primary and secondary BABG, significantly better results can be achieved if the operation is performed before eruption of the canine.

  8. 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.

  9. Probabilistic Study of Bone Remodeling Using Finite Element Analysis

    Science.gov (United States)

    Werner, C.; Gorla, R. S. R.

    2013-08-01

    The dynamic bone remodeling process is a computationally challenging research area that struggles to understand the actual mechanisms. It has been observed that a mechanical stimulus in the bone greatly affects the remodeling process. A 3D finite element model of a femur is created and a probabilistic analysis is performed on the model. The probabilistic analysis measures the sensitivities of various parameters related to the material properties, geometric properties, and the three load cases defined as Single Leg Stance, Abduction, and Adduction. The sensitivity of each parameter is based on the calculated maximum mechanical stimulus and analyzed at various values of probabilities ranging from 0.001 to 0.999. The analysis showed that the parameters associated with the Single Leg Stance load case had the highest sensitivity with a probability of 0.99 and the angle of the force applied to the joint of the proximal femur had the overall highest sensitivity

  10. Computed tomography of the alveolar bone; Computertomographie des Alveolarkammes

    Energy Technology Data Exchange (ETDEWEB)

    Schueller, H. [Bonn Univ. (Germany). Radiologische Klinik

    1996-03-01

    In addition to the conventional radiological methods used in odontology, computed tomography (CT) provides superposition-free images of the mandible and maxilla. Its value has been proved not only in cases of malignancy but also in many other problems. If an examination is performed with a slice thickness of less than 1.5 mm, the form and position of retained teeth in the alveolar bone, as well as subsequent lesions of neighboring permanent teeth, can be visualized so that early treatment can be planned. If the parodontal space of a retained tooth is visible, orthodontic intervention is possible. Precise assessment of horizontal or vertical bone loss is essential in inflammatory dental diseases. The morphology and extent of benign cystic lesions are also shown by CT. With CT surgical strategy of an intended implant therapy can take into account the remaining bone substance and the exact position of nerves and foramina. If such therapy is possible, the location, form and number of implants are easily defined. (orig.) [Deutsch] Die Computertomographie ermoeglicht in Ergaenzung zu den in der Zahnheilkunde gebraeuchlichen radiologischen Untersuchungsverfahren eine ueberlagerungsfreie Darstellung von Ober- und Unterkiefer. Neben der bereits etablierten Anwendung der CT bei malignen Erkrankungen hat sich ihr Einsatz bei weiteren Fragestellungen bewaehrt. Wird die Untersuchung mit einer Schichtdicke von weniger als 1,5 mm durchgefuehrt, lassen sich Form und Lage retinierter Zaehne im Kieferknochen und die durch die retinierten Zaehne verursachten Schaeden an bleibenden Zaehnen beurteilen, so dass eine fruehzeitige Therapie moeglich ist. Laesst sich der Parodontalspalt des retinierten Zahnes abgrenzen, ist eine kieferorthopaedische Einordnung moeglich. Bei entzuendlichen Zahnerkrankungen ist der horizontale und vertikale Knochenabbau genau zu bestimmen. Die Morphologie und Ausdehnung von benignen zystischen Raumforderungen ist mit der CT erfassbar. Vor einer beabsichtigten

  11. Is bone transplantation the gold standard for repair of alveolar bone defects?

    Directory of Open Access Journals (Sweden)

    Cassio Eduardo Raposo-Amaral

    2014-01-01

    Full Text Available New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate, compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7 defects were repaired with autogenous bone grafts; Group 2 (n = 5 defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5 defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5 defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6 defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01 and 38.35% ± 19.59% (p = 0.06 of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30 and 61.80% ± 2.14% (p = 0.88 of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone.

  12. Is bone transplantation the gold standard for repair of alveolar bone defects?

    Science.gov (United States)

    Raposo-Amaral, Cassio Eduardo; Bueno, Daniela Franco; Almeida, Ana Beatriz; Jorgetti, Vanda; Costa, Cristiane Cabral; Gouveia, Cecília Helena; Vulcano, Luiz Carlos; Fanganiello, Roberto D; Passos-Bueno, Maria Rita

    2014-01-01

    New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone. PMID:24551445

  13. Inflammatory and Bone Remodeling Responses to the Cytolethal Distending Toxins

    OpenAIRE

    2014-01-01

    The cytolethal distending toxins (CDTs) are a family of exotoxins produced by a wide range of Gram-negative bacteria. They are known for causing genotoxic stress to the cell, resulting in growth arrest and eventually apoptotic cell death. Nevertheless, there is evidence that CDTs can also perturb the innate immune responses, by regulating inflammatory cytokine production and molecular mediators of bone remodeling in various cell types. These cellular and molecular events may in turn have an...

  14. Inflammatory and bone remodeling responses to the cytolethal distending toxins

    OpenAIRE

    2014-01-01

    The cytolethal distending toxins (CDTs) are a family of exotoxins produced by a wide range of Gram-negative bacteria. They are known for causing genotoxic stress to the cell, resulting in growth arrest and eventually apoptotic cell death. Nevertheless, there is evidence that CDTs can also perturb the innate immune responses, by regulating inflammatory cytokine production and molecular mediators of bone remodeling in various cell types. These cellular and molecular events may in turn have an e...

  15. Bone marrow metastases from alveolar rhabdomyosarcoma with impressive FDG PET/CT finding but less-revealing bone scintigraphy.

    Science.gov (United States)

    Yang, Jigang; Zhen, Lishi; Zhuang, Hongming

    2013-12-01

    An 18F-FDG PET/CT scan was performed in a 26-year-old man with a known alveolar rhabdomyosarcoma for staging. The PET/CT scan showed abnormally increased FDG activity involving almost all bones in the imaged regions. In contrast, 99mTc-MDP whole-body bone scan demonstrated only very limited bone metastases.

  16. External bone remodeling after injectable calcium-phosphate cement in benign bone tumor: two cases in the hand.

    Science.gov (United States)

    Ichihara, S; Vaiss, L; Acciaro, A L; Facca, S; Liverneaux, P

    2015-12-01

    Bone remodeling commonly occurred after fracture and curettage benign bone tumor. A lot of previous articles reported "internal" trabecular bone remodeling. There were no previous clinical reports about "external" cortical bone remodeling. We present here 2 clinical cases of "external" bone remodeling after injectable calcium-phosphate in benign bone tumor in the hand. In two cases of benign bone tumor, we performed complete removal of the tumor and immediate filling of the metacarpal bone with injectable calcium-phosphate cement Arexbone(®) from the mechanical viewpoint. With respect to the shape of the calcium-phosphate, by using an injection-type, calcium-phosphate is adhered uniformly to the bone cortex by injecting, remodeling has been promoted. After 5 and 8years, both cases were no recurrences, and the shape of the metacarpal looked close to the contralateral side. These findings supposed to be concerned with potential self-healing and self-protection mechanism in human body.

  17. Augmentation of residual alveolar bone height with tissue engineering for dental implant placement

    Directory of Open Access Journals (Sweden)

    S M Balaji

    2014-01-01

    Full Text Available The challenge of correcting deficient vertical alveolar height for dental implant placement has been there since dental implants came in to regular clinical placement. The ability of various methods to increase the residual alveolar height has met with varying results. The primary reason is that the techniques were not quite successful in maintaining the required residual alveolar height. Use of Bone Morphogentic Protein, especially rhBMP-2 has been met with high degree of success in deficient vertical alveolar height in a mandibular ridge. The demonstration of this using a case has been presented here.

  18. Contour changes in human alveolar bone following tooth extraction of the maxillary central incisor.

    Science.gov (United States)

    Li, Bei; Wang, Yao

    2014-12-01

    The purpose of this study was to apply cone-beam computed tomography (CBCT) to observe contour changes in human alveolar bone after tooth extraction of the maxillary central incisor and to provide original morphological evidence for aesthetic implant treatment in the maxillary anterior area. Forty patients were recruited into the study. Each patient had two CBCT scans (CBCT I and CBCT II), one taken before and one taken three months after tooth extraction of maxillary central incisor (test tooth T). A fixed anatomic reference point was used to orient the starting axial slice of the two scans. On three CBCT I axial slices, which represented the deep, middle, and shallow layers of the socket, labial and palatal alveolar bone widths of T were measured. The number of sagittal slices from the start point to the pulp centre of T was recorded. On three CBCT II axial slices, the pulp centres of extracted T were oriented according to the number of moved sagittal slices recorded in CBCT I. Labial and palatal alveolar bone widths at the oriented sites were measured. On the CBCT I axial slice which represented the middle layer of the socket, sagittal slices were reconstructed. Relevant distances of T on the sagittal slice were measured, as were the alveolar bone width and tooth length of the opposite central incisor. On the CBCT II axial slice, which represented the middle layer of the socket, relevant distances recorded in CBCT I were transferred on the sagittal slice. The height reduction of alveolar bone on labial and palatal sides was measured, as were the alveolar bone width and tooth length of the opposite central incisor at the oriented site. Intraobserver reliability assessed by intraclass correlation coefficients (ICCs) was high. Paired sample t-tests were performed. The alveolar bone width and tooth length of the opposite central incisor showed no statistical differences (P<0.05). The labial alveolar bone widths of T at the deep, middle, and shallow layers all showed

  19. Early reversal cells in adult human bone remodeling

    DEFF Research Database (Denmark)

    Abdelgawad, Mohamed Essameldin; Delaissé, Jean-Marie; Hinge, Maja

    2016-01-01

    The mechanism coupling bone resorption and formation is a burning question that remains incompletely answered through the current investigations on osteoclasts and osteoblasts. An attractive hypothesis is that the reversal cells are likely mediators of this coupling. Their nature is a big matter...... of debate. The present study performed on human cancellous bone is the first one combining in situ hybridization and immunohistochemistry to demonstrate their osteoblastic nature. It shows that the Runx2 and CD56 immunoreactive reversal cells appear to take up TRAcP released by neighboring osteoclasts...... demonstrates that reversal cells colonizing bone surfaces right after resorption are osteoblast-lineage cells, and extends to adult human bone remodeling their role in rendering eroded surfaces osteogenic....

  20. Effects of oestrogen deficiency on the alveolar bone of rats with experimental periodontitis.

    Science.gov (United States)

    Xu, Xin-Chen; Chen, Hui; Zhang, Xi; Zhai, Zan-Jing; Liu, Xu-Qiang; Zheng, Xin-Yi; Zhang, Jun; Qin, An; Lu, Er-Yi

    2015-09-01

    Periodontitis is an inflammatory disease characterized by loss of connective tissue and alveolar bone, and osteoporosis is a common disease characterized by a systemic impairment of bone mass and microarchitecture. To date, the association between periodontitis and osteoporosis has remained to be fully elucidated. In the present study, an experimental rat model of periodontitis was used to explore the effects of oestrogen deficiency‑induced osteoporosis on the maxillary alveolar bone. Forty‑four female, six‑month‑old Sprague‑Dawley rats were randomly divided into four groups: Control, ligature, ovariectomized (OVX), and OVX + ligature. One month after ovariectomy, rats in the ligature and OVX + ligature groups received ligatures on their first and second maxillary molars for 1 month. Fluorescent labelling was performed prior to sacrificing the animals. At the end of the experiment, the maxillae and serum were collected and subjected to micro‑computed tomography analysis, confocal laser‑scanning microscopic observation, Van Gieson's fuchsin staining, tartrate‑resistant acid phosphatase staining and ELISA. Ligatures slightly reduced the alveolar bone mineral density (BMD) and bone formation rate, but significantly reduced alveolar crest height (ACH). Ovariectomy reduced the alveolar BMD, impaired the trabecular structure, reduced the bone formation rate and increased the serum levels of bone resorption markers. Animals in the OVX + ligature group exhibited a lower alveolar BMD, a poorer trabecular structure, a reduced ACH, a lower bone formation rate and higher serum levels of bone resorption markers compared with those in the control group. The results of the present study showed that ovariectomy enhanced alveolar bone loss and reduced the ACH of rats with experimental periodontitis. Thus, post‑menopausal osteoporosis may influence the progression of periodontitis.

  1. 3D computed tomographic evaluation of secondary alveolar bone grafts in cleft lip and palate patients

    Energy Technology Data Exchange (ETDEWEB)

    Ohkubo, Fumio; Akai, Hidemi; Hosaka, Yoshiaki [Showa Univ., Tokyo (Japan). School of Medicine

    2001-04-01

    Alveolar bone grafting in patients with cleft lip and palate has becomes a routine part of most treatment regimes. This study was undertaken to estimate how much bone needs to be grafted into the cleft cavity and to evaluate the grafted bone using 3-DCT over a period from the early postoperative stage to after one year. Seventy-five patients divided into four groups according to the type of cleft were studied. All patients underwent secondary alveolar bone grafting using particulate cancellous bone from the anterior iliac crest. The bone graft areas were divided into two regions: the extra-cleft region and the intra-cleft region. The weight and the volume of the grafted bone were correlated and the average density was 1.5 g/ml regardless of the cleft type. The bone in the extra-cleft region could be seen in almost all slices of the CT scans, from the lower alveolar process to the piriform aperture. The extra-cleft graft ratio of unilateral and bilateral cleft lip and palate is higher than that of cleft lip and alveolus. The extra-cleft grafting is necessary to restore facial symmetry. The grafted bone was decreased in both height and volume following three months and adequate bone bridging was maintained for one year. We concluded that 3-DCT findings are one of the most valuable methods to evaluate postoperative conditions after alveolar bone grafting. (author)

  2. A contemporary perspective on techniques for the clinical assessment of alveolar bone

    Energy Technology Data Exchange (ETDEWEB)

    Hausmann, E. (State Univ. of New York, Buffalo (USA))

    1990-03-01

    Radiographic techniques, traditional ones as well as newer ones under development, for clinically assessing alveolar bone are critically assessed. Traditional intraoral radiography is reexamined, in particular with regard to the accuracy with which the alveolar crest is seen. Evidence is presented for a more accurate representation of the alveolar crest on bitewings rather than periapical films. Application in periodontics of newer radiographic techniques, subtraction radiography, and single and dual photon aborptiometry presently under clinical development are discussed in regard to their potential and limitations. Similarly, radiopharmaceuticals to evaluate the metabolic status of alveolar bone are discussed as well as the potential for using analyses of gingival crevice fluid as a window for assessment of alveolar crest metabolism. 46 references.

  3. 上颌快速扩弓对小型猪后牙颊侧骨板改建影响的锥体束CT研究%Cone-beam computerized tomography evaluation of the effects of RME on buccal alveolar bone remodeling of maxillary posterior teeth in mini-pigs

    Institute of Scientific and Technical Information of China (English)

    付鼎; 厉松; 马玉洁; 刘鹏飞

    2013-01-01

    目的 通过定期拍摄锥体束CT(CBCT,Cone-Beam CT)观察小型猪扩弓前后及保持期的后牙颊侧骨板变化,了解扩弓力如何影响后牙颊侧骨板的改建.方法 选用10月龄雄性巴马小型猪8只,随机分为实验组5只,对照组3只.分别在扩弓前(T1),扩弓10天后(T2),保持3个月(T3)后拍摄CBCT,测量后牙颊侧牙槽骨高度和厚度的变化(△BMBL,△BBT).结果 上颌后牙颊侧牙槽骨高度指标BMBL和厚度指标BBT在T2期与对照组相比均出现明显变化(P<0.05),T3期与T2期相比,BMBL和BBT均无明显改变(P>0.05);△BMBL与△BBT之间存在显著性相关(γ=-0.96,P<0.01),扩弓前BBT与△BBT、△BMBL之间存在显著性相关(γ=-0.90,P<0.05;γ=-0.84,P<0.05).结论 上颌快速扩弓后颊侧牙槽骨高度、厚度均发生明显减小;扩弓前颊侧牙槽骨厚度与发生牙槽骨吸收的可能性存在负相关,能为临床选择扩弓方式提供一定参考依据.%Objective To explore the changes of maxillary buccal bone before RME,after RME and post retention using CBCT 3-dimensional imaging.Methods Eight male Bama mini-pigs at 10 months of age were randomly divided into two groups:Five pigs were in the experimental group and 3 in the control group.Before RME (T1),after RME (T2),3 months after retention (T3),all pigs were scanned using CBCT to analyze the thickness and height changes of buccal bone (BBT,△BMBL).Results BMBL,BBT representing the maxillary buccal alveolar bone height and thickness had significant changes at T2 compared with control group (P < 0.05).BMBL and BBT had no significant change between T3 and T2 (P>0.05).Significant corrlation was found between △BMBL and △BBT (γ=-0.96,P<0.01),between BBT at T1 and △MBBT (γ=-0.90,P<0.05),between BBT at T1 and △BMBL (γ=-0.84,P<0.05).Conclusions Alveolar bone height and thickness decreased significantly after RME and the buccal alveolar bone thickness before RME had negative correlation with the

  4. Alteration of proteoglycan sulfation affects bone growth and remodeling.

    Science.gov (United States)

    Gualeni, Benedetta; de Vernejoul, Marie-Christine; Marty-Morieux, Caroline; De Leonardis, Fabio; Franchi, Marco; Monti, Luca; Forlino, Antonella; Houillier, Pascal; Rossi, Antonio; Geoffroy, Valerie

    2013-05-01

    Diastrophic dysplasia (DTD) is a chondrodysplasia caused by mutations in the SLC26A2 gene, leading to reduced intracellular sulfate pool in chondrocytes, osteoblasts and fibroblasts. Hence, proteoglycans are undersulfated in the cartilage and bone of DTD patients. To characterize the bone phenotype of this skeletal dysplasia we used the Slc26a2 knock-in mouse (dtd mouse), that was previously validated as an animal model of DTD in humans. X-rays, bone densitometry, static and dynamic histomorphometry, and in vitro studies revealed a primary bone defect in the dtd mouse model. We showed in vivo that this primary bone defect in dtd mice is due to decreased bone accrual associated with a decreased trabecular and periosteal appositional rate at the cell level in one month-old mice. Although the osteoclast number evaluated by histomorphometry was not different in dtd compared to wild-type mice, urine analysis of deoxypyridinoline cross-links and serum levels of type I collagen C-terminal telopeptides showed a higher resorption rate in dtd mice compared to wild-type littermates. Electron microscopy studies showed that collagen fibrils in bone were thinner and less organized in dtd compared to wild-type mice. These data suggest that the low bone mass observed in mutant mice could possibly be linked to the different bone matrix compositions/organizations in dtd mice triggering changes in osteoblast and osteoclast activities. Overall, these results suggest that proteoglycan undersulfation not only affects the properties of hyaline cartilage, but can also lead to unbalanced bone modeling and remodeling activities, demonstrating the importance of proteoglycan sulfation in bone homeostasis. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. The osteocyte as an orchestrator of bone remodeling: an engineer’s perspective

    NARCIS (Netherlands)

    van Oers, R.F.M.; Klein-Nulend, J.; Bacabac, R.G.

    2014-01-01

    Bone is adapted to mechanical loading. The trabeculae in cancellous bone and the osteons in cortical bone are aligned to the mechanical loading direction. Our bones are constantly remodeled by bone-resorbing osteoclasts and bone-forming osteoblasts, cooperating in so-called basic multicellular units

  6. An Experimental Study of Radiographic Density of Alveolar Bone and Cortical Thickness of Mandible by Osteoporosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byeong Do [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Wonkwang University, Iksan (Korea, Republic of)

    2000-12-15

    To evaluate the effect of the systemic osteoporosis on radiographic density of alveolar bone and cortical thickness of mandible. The bone mineral density values of lumbar and femur were measured by dual-energy X-ray absorptiometry and T scores of lumbar, femur were obtained respectively. Radiographic densities of alveolar bones and panorama mandibular index (PMI, represents as cortical thickness) were analysed statistically according to age and T score variavles. The radiographic density of alveolar bone of maxillary molar showed significant difference by age and femur T group. That of mandibular molar showed significant difference between femur T group. Panorama mandibular index showed significant difference between age groups. The radiographic density of alvealar bones was more dependent on age femur T than lumbar T. Cortical thickness of mandible was correlated with increasing age.

  7. Influence of alcohol consumption on alveolar bone level associated with ligature-induced periodontitis in rats

    Directory of Open Access Journals (Sweden)

    Daniela Martins de Souza

    2009-09-01

    Full Text Available Alcohol consumption is a risk indicator for periodontal disease. The purpose of this study was to morphometrically evaluate the influence of alcohol consumption on alveolar bone level associated with ligature-induced periodontitis in rats. Thirty-six female rats (Wistar, 120 days-old were randomly divided into three groups that received a daily administration of a water diet (control, n = 12, a 10% alcohol diet (10% ethanol, n = 12 or a 20% alcohol diet (20% ethanol, n = 12. Four weeks after the onset of the experiment, cotton ligatures were placed around the cervix of the upper right second molar in six rats. The other 6 rats in each group remained unligated. The rats were sacrificed four weeks after ligature placement. The maxillary bones were removed and alveolar bone loss was analyzed by measuring the distance between the cementoenamel junction and the alveolar bone crest at 2 buccal and 2 palatal sites on the upper right second molar. Analyses between the ligated and unligated groups showed that the presence of ligature induced alveolar bone loss (p 0.05. In the ligated groups, rats receiving 20% ethanol showed significantly greater bone loss compared to control rats or rats receiving 10% ethanol. These results demonstrate that alcohol consumption may increase alveolar bone loss in female rats in a dose-dependent manner.

  8. Interstitial fluid flow in canaliculi as a mechanical stimulus for cancellous bone remodeling: in silico validation.

    Science.gov (United States)

    Kameo, Yoshitaka; Adachi, Taiji

    2014-08-01

    Cancellous bone has a dynamic 3-dimensional architecture of trabeculae, the arrangement of which is continually reorganized via bone remodeling to adapt to the mechanical environment. Osteocytes are currently believed to be the major mechanosensory cells and to regulate osteoclastic bone resorption and osteoblastic bone formation in response to mechanical stimuli. We previously developed a mathematical model of trabecular bone remodeling incorporating the possible mechanisms of cellular mechanosensing and intercellular communication in which we assumed that interstitial fluid flow activates the osteocytes to regulate bone remodeling. While the proposed model has been validated by the simulation of remodeling of a single trabecula, it remains unclear whether it can successfully represent in silico the functional adaptation of cancellous bone with its multiple trabeculae. In the present study, we demonstrated the response of cancellous bone morphology to uniaxial or bending loads using a combination of our remodeling model with the voxel finite element method. In this simulation, cancellous bone with randomly arranged trabeculae remodeled to form a well-organized architecture oriented parallel to the direction of loading, in agreement with the previous simulation results and experimental findings. These results suggested that our mathematical model for trabecular bone remodeling enables us to predict the reorganization of cancellous bone architecture from cellular activities. Furthermore, our remodeling model can represent the phenomenological law of bone transformation toward a locally uniform state of stress or strain at the trabecular level.

  9. Can experimental data in humans verify the finite element-based bone remodeling algorithm?

    DEFF Research Database (Denmark)

    Wong, Christian; Gehrchen, P Martin; Kiaer, Thomas

    2008-01-01

    A finite element analysis-based bone remodeling study in human was conducted in the lumbar spine operated on with pedicle screws. Bone remodeling results were compared to prospective experimental bone mineral content data of patients operated on with pedicle screws....

  10. Simulating Bone Loss in Microgravity Using Mathematical Formulations of Bone Remodeling

    Science.gov (United States)

    Pennline, James A.

    2009-01-01

    Most mathematical models of bone remodeling are used to simulate a specific bone disease, by disrupting the steady state or balance in the normal remodeling process, and to simulate a therapeutic strategy. In this work, the ability of a mathematical model of bone remodeling to simulate bone loss as a function of time under the conditions of microgravity is investigated. The model is formed by combining a previously developed set of biochemical, cellular dynamics, and mechanical stimulus equations in the literature with two newly proposed equations; one governing the rate of change of the area of cortical bone tissue in a cross section of a cylindrical section of bone and one governing the rate of change of calcium in the bone fluid. The mechanical stimulus comes from a simple model of stress due to a compressive force on a cylindrical section of bone which can be reduced to zero to mimic the effects of skeletal unloading in microgravity. The complete set of equations formed is a system of first order ordinary differential equations. The results of selected simulations are displayed and discussed. Limitations and deficiencies of the model are also discussed as well as suggestions for further research.

  11. Effects of loading frequency on the functional adaptation of trabeculae predicted by bone remodeling simulation.

    Science.gov (United States)

    Kameo, Yoshitaka; Adachi, Taiji; Hojo, Masaki

    2011-08-01

    The process of bone remodeling is regulated by metabolic activities of many bone cells. While osteoclasts and osteoblasts are responsible for bone resorption and formation, respectively, activities of these cells are believed to be controlled by a mechanosensory system of osteocytes embedded in the extracellular bone matrix. Several experimental and theoretical studies have suggested that the strain-derived interstitial fluid flow in lacuno-canalicular porosity serves as the prime mover for bone remodeling. Previously, we constructed a mathematical model for trabecular bone remodeling that interconnects the microscopic cellular activities with the macroscopic morphological changes in trabeculae through the mechanical hierarchy. This model assumes that fluid-induced shear stress acting on osteocyte processes is a driving force for bone remodeling. The validity of this model has been demonstrated with a remodeling simulation using a two-dimensional trabecular model. In this study, to investigate the effects of loading frequency, which is thought to be a significant mechanical factor in bone remodeling, we simulated morphological changes of a three-dimensional single trabecula under cyclic uniaxial loading with various frequencies. The results of the simulation show the trabecula reoriented to the loading direction with the progress of bone remodeling. Furthermore, as the imposed loading frequency increased, the diameter of the trabecula in the equilibrium state was enlarged by remodeling. These results indicate that our simulation model can successfully evaluate the relationship between loading frequency and trabecular bone remodeling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. 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.

  13. In vitro culture and characterization of alveolar bone osteoblasts isolated from type 2 diabetics

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Dao-Cai [Department of Implant Dentistry, School of Stomatology, Fourth Military Medical University, Xi' an (China); Department of Stomatology, The 291st Hospital of P.L.A, Baotou (China); Li, De-Hua [Department of Implant Dentistry, School of Stomatology, Fourth Military Medical University, Xi' an (China); Ji, Hui-Cang [Military Sanatorium of Retired Cadres, Baotou (China); Rao, Guo-Zhou [Center of Laboratory, School of Stomatology, Xi' an Jiaotong University, Xi' an (China); Liang, Li-Hua [Department of Implant Dentistry, School of Stomatology, Fourth Military Medical University, Xi' an (China); Ma, Ai-Jie [Xi' an Technology University, Xi' an (China); Xie, Chao; Zou, Gui-Ke; Song, Ying-Liang [Department of Implant Dentistry, School of Stomatology, Fourth Military Medical University, Xi' an (China)

    2012-04-05

    In order to understand the mechanisms of poor osseointegration following dental implants in type 2 diabetics, it is important to study the biological properties of alveolar bone osteoblasts isolated from these patients. We collected alveolar bone chips under aseptic conditions and cultured them in vitro using the tissue explants adherent method. The biological properties of these cells were characterized using the following methods: alkaline phosphatase (ALP) chemical staining for cell viability, Alizarin red staining for osteogenic characteristics, MTT test for cell proliferation, enzyme dynamics for ALP contents, radio-immunoassay for bone gla protein (BGP) concentration, and ELISA for the concentration of type I collagen (COL-I) in the supernatant. Furthermore, we detected the adhesion ability of two types of cells from titanium slices using non-specific immunofluorescence staining and cell count. The two cell forms showed no significant difference in morphology under the same culture conditions. However, the alveolar bone osteoblasts received from type 2 diabetic patients had slower growth, lower cell activity and calcium nodule formation than the normal ones. The concentration of ALP, BGP and COL-I was lower in the supernatant of alveolar bone osteoblasts received from type 2 diabetic patients than in that received from normal subjects (P < 0.05). The alveolar bone osteoblasts obtained from type 2 diabetic patients can be successfully cultured in vitro with the same morphology and biological characteristics as those from normal patients, but with slower growth and lower concentration of specific secretion and lower combining ability with titanium than normal ones.

  14. Sclerostin Promotes Bone Remodeling in the Process of Tooth Movement

    Science.gov (United States)

    Shu, Rui; Bai, Ding; Sheu, Tzongjen; He, Yao; Yang, Xianrui; Xue, Chaoran; He, Yiruo; Zhao, Mengyuan; Han, Xianglong

    2017-01-01

    Tooth movement is a biological process of bone remodeling induced by mechanical force. Sclerostin secreted by osteocytes is mechanosensory and important in bone remodeling. However, little is known regarding the role of sclerostin in tooth movement. In this study, models of experimental tooth movement were established in rats and mice. Sclerostin expression was investigated with immunohistochemistry staining, and osteoclastic activity was analyzed with tartrate-resistant acid phosphatase (TRAP) staining. MLO-Y4 osteocyte-like cells underwent uniaxial compression and tension stress or were cultured in hypoxia conditions. Expression of sclerostin was assessed by RT-qPCR and ELISA. MLO-Y4 cells were cultured with recombinant human sclerostin (rhSCL) interference and then co-cultured with RAW264.7 osteoclast precursor cells. Expressions of RANKL and OPG were analyzed by RT-qPCR, and osteoclastic activity was assessed by TRAP staining. During tooth movement, sclerostin was expressed differently in compression and tension sites. In SOST knock-out mice, there were significantly fewer TRAP-positive cells than in WT mice during tooth movement in compression sites. In-vitro studies showed that the expression of sclerostin in MLO-Y4 osteocyte-like cells was not different under a uniaxial compression and tension force, whereas hypoxia conditions significantly increased sclerostin expression in MLO-Y4 cells. rhSCL interference increased the expression of RANKL and the RANKL/OPG ratio in MLO-Y4 cells and the osteoclastic induction ability of MLO-Y4 cells in experimental osteocyte-osteoclast co-culture. These data suggest that sclerostin plays an important role in the bone remodeling of tooth movement. PMID:28081119

  15. 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.

  16. The Ovariectomized Rat as a Model for Studying Alveolar Bone Loss in Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Bryan D. Johnston

    2015-01-01

    Full Text Available In postmenopausal women, reduced bone mineral density at the hip and spine is associated with an increased risk of tooth loss, possibly due to a loss of alveolar bone. In turn, having fewer natural teeth may lead to compromised food choices resulting in a poor diet that can contribute to chronic disease risk. The tight link between alveolar bone preservation, tooth retention, better nutritional status, and reduced risk of developing a chronic disease begins with the mitigation of postmenopausal bone loss. The ovariectomized rat, a widely used preclinical model for studying postmenopausal bone loss that mimics deterioration of bone tissue in the hip and spine, can also be used to study mineral and structural changes in alveolar bone to develop drug and/or dietary strategies aimed at tooth retention. This review discusses key findings from studies investigating mandible health and alveolar bone in the ovariectomized rat model. Considerations to maximize the benefits of this model are also included. These include the measurement techniques used, the age at ovariectomy, the duration that a rat is studied after ovariectomy and habitual diet consumed.

  17. The Ovariectomized Rat as a Model for Studying Alveolar Bone Loss in Postmenopausal Women

    Science.gov (United States)

    Johnston, Bryan D.; Ward, Wendy E.

    2015-01-01

    In postmenopausal women, reduced bone mineral density at the hip and spine is associated with an increased risk of tooth loss, possibly due to a loss of alveolar bone. In turn, having fewer natural teeth may lead to compromised food choices resulting in a poor diet that can contribute to chronic disease risk. The tight link between alveolar bone preservation, tooth retention, better nutritional status, and reduced risk of developing a chronic disease begins with the mitigation of postmenopausal bone loss. The ovariectomized rat, a widely used preclinical model for studying postmenopausal bone loss that mimics deterioration of bone tissue in the hip and spine, can also be used to study mineral and structural changes in alveolar bone to develop drug and/or dietary strategies aimed at tooth retention. This review discusses key findings from studies investigating mandible health and alveolar bone in the ovariectomized rat model. Considerations to maximize the benefits of this model are also included. These include the measurement techniques used, the age at ovariectomy, the duration that a rat is studied after ovariectomy and habitual diet consumed. PMID:26060817

  18. VEGF inhibition as possible therapy in spondyloarthritis patients: Targeting bone remodelling.

    Science.gov (United States)

    Lacout, Alexis; Carlier, Robert Yves; El Hajjam, Mostafa; Marcy, Pierre Yves

    2017-04-01

    Spondyloarthritis refers to a group of chronic inflammatory rheumatic diseases that predominantly affects the axial skeleton, causing pain and stiffness. Human bone is highly dynamic organ that interacts with a wide array cells and tissues. Process of bone remodelling relies on a delicate balance between bone formation and bone resorption, orchestrated by osteoblasts and osteoclasts. Disruption of this homeostatic balance of bone removal and replacement can manifest as inappropriate new bone formation found in spondylarthritis. We hypothesize that VEGF may promote bone remodelling, stimulate angiogenesis, and both osteoclastic and osteoblastic activity. Anti VEGF may be tested as a dedicated therapy to prevent bone remodelling in spondyloarthritis patients, namely in cases of aggressive disease. Bone remodelling could be monitored by using [18F]Fluoride PET scan.

  19. RETINOID RECEPTORS IN BONE AND THEIR ROLE IN BONE REMODELING

    Directory of Open Access Journals (Sweden)

    Petra eHenning

    2015-03-01

    Full Text Available Vitamin A (retinol is a necessary and important constituent of the body which is provided by food intake of retinyl esters and carotenoids. Vitamin A is known best for being important for vision, but in addition to the eye, vitamin A is necessary in numerous other organs in the body, including the skeleton. Vitamin A is converted to an active compound, all-trans-retinoic acid (ATRA, which is responsible for most of its biological actions. ATRA binds to intracellular nuclear receptors called retinoic acid receptors (RAR, RAR, RAR. RARs and closely related retinoid X receptors (RXR, RXR, RXR form heterodimers which bind to DNA and function as ligand activated transcription factors. It has been known for many years that hypervitaminosis A promotes skeleton fragility by increasing osteoclast formation and decreasing cortical bone mass. Some epidemiological studies have suggested that increased intake of vitamin A and increased serum levels of retinoids may decrease bone mineral density and increase fracture rate, but the literature on this is not conclusive. The current review summarizes how vitamin A is taken up by the intestine, metabolized, stored in the liver and processed to ATRA. ATRA’s effects on formation and activity of osteoclasts and osteoblasts are outlined, and a summary of clinical data pertaining to vitamin A and bone is presented.

  20. Relationship between alveolar bone measured by /sup 125/I absorptiometry with analysis of standardized radiographs: 1. Magiscan

    Energy Technology Data Exchange (ETDEWEB)

    Hausmann, E.; Ortman, L.F.; McHenry, K.; Fallon, J.

    1982-05-01

    Previous studies have shown that /sup 125/I absorptiometry gives an accurate and sensitive measure of alveolar bone mass. The purpose of this study was to determine the relationship between alveolar bone mass determined by /sup 125/I absorptiometry and bone density obtained by analysis of standardized intraoral radiographs by the Magiscan System. A defect of increasing size was made at one site of the alveolar bone in a human skull. The amount of bone remaining at each step was calculated using /sup 125/I absorptiometry. Standardized radiographs were also taken at each step and the relative density in the area of the defect was determined by the Magiscan System. The Magiscan's System Computer Memory permits analysis of identical areas on a longitudinal series of films of the same alveolar bone location. The results indicate that in estimating amounts of alveolar bone the Magiscan analysis of standardized intraoral radiography is similar in sensitivity and accuracy to /sup 125/I absorptiometry.

  1. Platelet-Rich Fibrin Promotes Periodontal Regeneration and Enhances Alveolar Bone Augmentation

    Directory of Open Access Journals (Sweden)

    Qi Li

    2013-01-01

    Full Text Available In the present study we have determined the suitability of platelet-rich fibrin (PRF as a complex scaffold for periodontal tissue regeneration. Replacing PRF with its major component fibrin increased mineralization in alveolar bone progenitors when compared to periodontal progenitors, suggesting that fibrin played a substantial role in PRF-induced osteogenic lineage differentiation. Moreover, there was a 3.6-fold increase in the early osteoblast transcription factor RUNX2 and a 3.1-fold reduction of the mineralization inhibitor MGP as a result of PRF application in alveolar bone progenitors, a trend not observed in periodontal progenitors. Subcutaneous implantation studies revealed that PRF readily integrated with surrounding tissues and was partially replaced with collagen fibers 2 weeks after implantation. Finally, clinical pilot studies in human patients documented an approximately 5 mm elevation of alveolar bone height in tandem with oral mucosal wound healing. Together, these studies suggest that PRF enhances osteogenic lineage differentiation of alveolar bone progenitors more than of periodontal progenitors by augmenting osteoblast differentiation, RUNX2 expression, and mineralized nodule formation via its principal component fibrin. They also document that PRF functions as a complex regenerative scaffold promoting both tissue-specific alveolar bone augmentation and surrounding periodontal soft tissue regeneration via progenitor-specific mechanisms.

  2. Platelet-rich fibrin promotes periodontal regeneration and enhances alveolar bone augmentation.

    Science.gov (United States)

    Li, Qi; Pan, Shuang; Dangaria, Smit J; Gopinathan, Gokul; Kolokythas, Antonia; Chu, Shunli; Geng, Yajun; Zhou, Yanmin; Luan, Xianghong

    2013-01-01

    In the present study we have determined the suitability of platelet-rich fibrin (PRF) as a complex scaffold for periodontal tissue regeneration. Replacing PRF with its major component fibrin increased mineralization in alveolar bone progenitors when compared to periodontal progenitors, suggesting that fibrin played a substantial role in PRF-induced osteogenic lineage differentiation. Moreover, there was a 3.6-fold increase in the early osteoblast transcription factor RUNX2 and a 3.1-fold reduction of the mineralization inhibitor MGP as a result of PRF application in alveolar bone progenitors, a trend not observed in periodontal progenitors. Subcutaneous implantation studies revealed that PRF readily integrated with surrounding tissues and was partially replaced with collagen fibers 2 weeks after implantation. Finally, clinical pilot studies in human patients documented an approximately 5 mm elevation of alveolar bone height in tandem with oral mucosal wound healing. Together, these studies suggest that PRF enhances osteogenic lineage differentiation of alveolar bone progenitors more than of periodontal progenitors by augmenting osteoblast differentiation, RUNX2 expression, and mineralized nodule formation via its principal component fibrin. They also document that PRF functions as a complex regenerative scaffold promoting both tissue-specific alveolar bone augmentation and surrounding periodontal soft tissue regeneration via progenitor-specific mechanisms.

  3. The effects of proteasome inhibitors on bone remodeling in multiple myeloma.

    Science.gov (United States)

    Zangari, Maurizio; Suva, Larry J

    2016-05-01

    Bone disease is a characteristic feature of multiple myeloma, a malignant plasma cell dyscrasia. In patients with multiple myeloma, the normal process of bone remodeling is dysregulated by aberrant bone marrow plasma cells, resulting in increased bone resorption, prevention of new bone formation, and consequent bone destruction. The ubiquitin-proteasome system, which is hyperactive in patients with multiple myeloma, controls the catabolism of several proteins that regulate bone remodeling. Clinical studies have reported that treatment with the first-in-class proteasome inhibitor bortezomib reduces bone resorption and increases bone formation and bone mineral density in patients with multiple myeloma. Since the introduction of bortezomib in 2003, several next-generation proteasome inhibitors have also been used clinically, including carfilzomib, oprozomib, ixazomib, and delanzomib. This review summarizes the available preclinical and clinical evidence regarding the effect of proteasome inhibitors on bone remodeling in multiple myeloma. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Ozone treatment of alveolar bone in the cape chacma baboon does not enhance healing following trauma.

    Science.gov (United States)

    Kotze, Marthinus; Bütow, Kürt-W; Olorunju, Steve A; Kotze, Harry F

    2014-06-01

    In the international literature, the role of Ozone (O3) in the advancement in alveolar bone healing in the absence of bone pathology was not tested before. The purpose of this study was to evaluate alveolar bone regeneration after a bone defect was created and treated with a single topical administration of O3. Alveolar bone defects were created on five healthy chacma baboons. One side of the maxilla and mandible was topically treated with a single treatment of an O3/O2 mixture (3,5-4 % O3), while the opposite sides were not treated and thus served as control. Regeneration was measured radiologically, using a standardized gray scale, as the increase in bone density in the treatment area at 3 and 6 weeks post-operative and was statistically analyzed using multivariate analysis of variance (MANOVA). There were no significant differences in densities observed between the O3/O2 mixture treatment and the control (p > 0.05). A single O3 treatment did not increase alveolar bone healing over a 3- and 6-week period in the mandible and the maxilla.

  5. Bone regeneration by octacalcium phosphate collagen composites in a dog alveolar cleft model.

    Science.gov (United States)

    Matsui, K; Matsui, A; Handa, T; Kawai, T; Suzuki, O; Kamakura, S; Echigo, S

    2010-12-01

    Octacalcium phosphate (OCP) and porcine atelocollagen sponge composites (OCP/Col) markedly enhanced bone regeneration in a rat cranial defect model. To assess clinical application, the authors examined whether OCP/Col would enhance bone regeneration in an alveolar cleft model in an adult dog, which was assumed to reflect patients with alveolar cleft. Disks of OCP/Col or collagen were implanted into the defect and bone regeneration by OCP/Col or collagen was investigated 4 months after implantation. Macroscopically, the OCP/Col-treated alveolus was obviously augmented and occupied by radio-opacity, and the border between the original bone and the defect was indistinguishable. Histological analysis revealed it was filled and bridged with newly formed bone; a small quantity of the remaining implanted OCP was observed. X-ray diffraction patterns of the area of implanted OCP/Col indicated no difference from those of dog bone. In the collagen-treated alveolus, the hollowed alveolus was mainly filled with fibrous connective tissue, and a small amount of new bone was observed at the defect margin. These results suggest that bone was obviously repaired when OCP/Col was implanted into the alveolar cleft model in a dog, and OCP/Col would be a significant bone regenerative material to substitute for autogeneous bone.

  6. 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.

  7. 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.

  8. Bone remodelling in Neanderthal mandibles from the El Sidrón site (Asturias, Spain).

    Science.gov (United States)

    Martinez-Maza, Cayetana; Rosas, Antonio; García-Vargas, Samuel; Estalrrich, Almudena; de la Rasilla, Marco

    2011-08-23

    Skull morphology results from the bone remodelling mechanism that underlies the specific bone growth dynamics. Histological study of the bone surface from Neanderthal mandible specimens of El Sidrón (Spain) provides information about the distribution of the remodelling fields (bone remodelling patterns or BRP) indicative of the bone growth directions. In comparison with other primate species, BRP shows that Neanderthal mandibles from the El Sidrón (Spain) sample present a specific BRP. The interpretation of this map allows inferences concerning the growth directions that explain specific morphological traits of the Neanderthal mandible, such as its quadrangular shape and the posterior location of the mental foramen.

  9. Bone remodelling in Neanderthal mandibles from the El Sidrón site (Asturias, Spain)

    Science.gov (United States)

    Martinez-Maza, Cayetana; Rosas, Antonio; García-Vargas, Samuel; Estalrrich, Almudena; de la Rasilla, Marco

    2011-01-01

    Skull morphology results from the bone remodelling mechanism that underlies the specific bone growth dynamics. Histological study of the bone surface from Neanderthal mandible specimens of El Sidrón (Spain) provides information about the distribution of the remodelling fields (bone remodelling patterns or BRP) indicative of the bone growth directions. In comparison with other primate species, BRP shows that Neanderthal mandibles from the El Sidrón (Spain) sample present a specific BRP. The interpretation of this map allows inferences concerning the growth directions that explain specific morphological traits of the Neanderthal mandible, such as its quadrangular shape and the posterior location of the mental foramen. PMID:21307043

  10. Alveolar Ridge Conservation by Early Bone Formation After Tooth Extraction in Rabbits. A Histomorphological Study

    Science.gov (United States)

    Cantín, Mario; Olate, Sergio; Fuentes, Ramón; Vásquez, Bélgica

    2016-01-01

    SUMMARY Alveolar ridge volume loss is an irreversible process. To prevent this physiological event, which typically result in significant local anatomical changes in both the horizontal and the vertical dimension, some strategies are indicated to minimize the loss of ridge volume that typically follows tooth extraction. The purpose of this study was to evaluate if three different bone grafts could promote new bone formation in the alveolar socket following tooth extraction for the alveolar ridge conservation. First mandibular molars of male adults rabbits were extracted and the extraction sockets were randomly treated with three different bone grafts, one xenograft and two alloplastic grafts, and a group that received no treatment (blood clot). The extraction sockets of selected rabbits from each group were evaluated at 4, 6, or 8-week post-extraction. The results indicated that the extraction sockets treated with alloplastic graft (biphasic calcium phosphate) exhibited lamellar bone formation (6.5%) as early as four weeks after the extraction was performed. Moreover, the degree of new bone formation was significantly higher (P<0.05) in the extraction sockets treated with biphasic calcium phosphate at 8-week post-extraction than that in the other study groups. In this study, we demonstrated that the proposed animal model is useful to evaluate the bone formation after tooth extraction and the alveolar ridge conservation is feasible. The new bone formation and alveolar ridge preservation with bone graft after extraction of molar teeth, could result in the maintenance of sufficient bone volume to place an implant in an ideal restorative position without the need for ancillary implant site development procedures. PMID:27840551

  11. 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.

  12. Responses of tooth eruption and alveolar bone subject to somatic growth retardation in the rat.

    Science.gov (United States)

    Park, A W

    1981-06-01

    The morphogenesis and regression of the osteodental fissure formed by alveolar bone in the maxillary and mandibular regions has been investigated in relation to eruption of the dentition during and following a period of somatic retardation stemming from nutritional suppression. Fissural formation occurred above the first and second molars of the maxilla and mandible, morphologically within normal limits but retarded by two days. During eruption a sequence of cuspal perforations of the alveolar bone took place behind the edge of the alveolar crest which later disintegrated as the bulk of the crown moved upwards. The appearance of the specific cusps of the experimental animals was two days behind that of the controls. Eruption through the oral mucosa was fairly rapid and the deficit noted in the bone emergence phase was reduced to one day. As in control animals, fissural formation did not occur over the third molars which were totally encapsulated by bone. Eruption of third molars in experimental animals was similar to control observations- no difference in timing and the removal of the encapsulating bone being achieved by the rapid enlarging of a wedge-shaped area at the mesio-occlusal aspect. Observation of eruption through alveolar bone is regarded as a more accurate assessment of changes in the early phases.

  13. 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...... recruitment potential are already known. Here we draw the attention on the osteoblast recruitment potential of the collagen that is freshly demineralized by the osteoclast. Our evidence is based on observations on adult human cancellous bone, combined with in vitro assays. First, freshly eroded surfaces where...... osteoblasts have to be recruited show the presence of non-degraded demineralized collagen and close cell-collagen interactions, as revealed by electron microscopy, while surface-bound collagen strongly attracts osteoblast lineage cells in a transmembrane migration assay. Compared with other extracellular...

  14. Effect of obesity on alveolar bone loss in experimental periodontitis in Wistar rats

    Directory of Open Access Journals (Sweden)

    Giliano Nicolini Verzeletti

    2012-04-01

    Full Text Available Obesity has been linked to higher inflammatory status and periodontal breakdown. OBJECTIVE: The purpose of this study was to investigate the effect of obesity on alveolar bone loss in experimental periodontitis in rats. MATERIAL AND METHODS: Twenty-four female Wistar rats were randomly divided into two groups: obese (n=13, which were fed with "cafeteria diet" (CAF diet - high amounts of sucrose and fat for 90 days in order to gain weight, and non-obese (n=11 regularly fed rats. Ligature-induced experimental periodontitis was created in all animals. Body weight differed statistically between obese and non-obese groups (277.59 and 223.35 g, respectively at the moment of the ligature placement. Morphometric registration of alveolar bone loss was carried out after 30 days of ligature placement to determine the effect of obesity on the progression of experimental periodontitis. RESULTS: Intra-group comparisons showed significantly higher alveolar bone loss mean values in maxillary teeth with ligature (P<0.05. Alveolar bone loss [mean (SD, mm] was not statistically different between obese and non-obese groups [0.71 (0.09 and 0.65 (0.07 mm, respectively]. However, when palatal sides are analyzed separately, obese group presented significantly higher alveolar bone loss (P<0.05 as compared to non-obese [0.68 (0.12 and 0.53 (0.13 mm, respectively]. CONCLUSIONS: In spite of the weak differences, it is possible to conclude that the progression of alveolar bone loss in ligature-induced periodontitis can be potentially influenced by body weight in rats.

  15. Bone response to buccal tooth movements-with and without flapless alveolar decortication.

    Science.gov (United States)

    Ruso, Stephen; Campbell, Phillip M; Rossmann, Jeffrey; Opperman, Lynne A; Taylor, Reginald W; Buschang, Peter H

    2014-12-01

    To evaluate the biological response of alveolar bone surrounding maxillary second premolars to flapless alveolar decortication and moderate, continuous forces in a buccal direction. Using a randomized split-mouth experimental design, unilateral alveolar decortication was performed with a piezosurgery unit around the maxillary second premolars of six female dogs. The contralateral side received a sham surgery. The maxillary second premolars were moved buccally with archwires (initial 163.9 cN expansive force) for 9 weeks, followed by 2 weeks of consolidation. Intraoral, radiographic, and model measurements were performed to evaluate tooth movements; the amount and quality of surrounding bone were quantified using micro-CT; bone formation was evaluated histologically. The experimental premolars were expanded and tipped significantly (P < 0.05) more than the control premolars (1.35 times and 2.05 times as much, respectively). Peak rates of tooth movement occurred around 5 weeks. Dehiscenses were observed on both the experimental and control sides, with no statistically significant side differences in buccal bone height (BBH). Micro-CT analyses showed less mature bone in the apico-buccal and cervico-lingual regions around the experimental teeth. Hematoxylin and eosin sections demonstrated fenestrations on the cervico-buccal bone on both sides. The experimental side showed substantially more new bone formation and modeling of apico-buccal, cervico-lingual, and buccal bone than the control side. Archwire expansion resulted in reductions in BBH. Piezosurgical flapless alveolar decortication, in combination with archwire expansion, increased tooth movements and tipping and produced less bone, less dense bone, and less mature bone. © The Author 2013. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. Alveolar bone mass in pre- and postmenopausal women with serum calcium as a marker: A comparative study

    Directory of Open Access Journals (Sweden)

    Amitha Ramesh

    2011-01-01

    Conclusion: Postmenopausal women exhibit a reduced alveolar bone mass and lowered levels of serum total calcium with the increasing age. These changes may be useful indicators for low skeletal bone mineral density or osteoporosis.

  17. Complications related to bone augmentation procedures of localized defects in the alveolar ridge. A retrospective clinical study

    DEFF Research Database (Denmark)

    Jensen, Anders Torp; Jensen, Simon Storgård; Worsaae, Nils

    2016-01-01

    PURPOSE: This retrospective clinical study aims to evaluate complications after augmentation of localized bone defects of the alveolar ridge. METHODS: From standardized registrations, the following complications related to bone augmentation procedures were recorded: soft tissue dehiscence, infect...

  18. Bone mineral density, Bone mineral contents, MMP-8 and MMP-9 levels in Human Mandible and alveolar bone: Simulated microgravity

    Science.gov (United States)

    Rai, Balwant; Kaur, Jasdeep; Catalina, Maria

    Exposure to microgravity has been associated with several physiological changes in astronauts and cosmonauts, including an osteoporosis-like loss of bone mass. It has been reported that head-down tilt bed-rest studies mimic many of the observations seen in flights. There is no study on the correlation on effects of mandibular bone and alveolar bone loss in both sex in simulating microgravity. This study was designed to determine the Bone mineral density and GCF MMP-8 MMP-9 in normal healthy subject of both sexes in simulated microgravity condition of -6 head-down-tilt (HDT) bed rest. The subjects of this investigation were 10 male and 10 female volunteers participated in three weeks 6 HDT bed-rest exposure. The Bone density and bone mineral contents were measured by dual energy X-ray absorptiometry before and in simulated microgravity. The GCF MMP-8 MMP-8 were measured by Enzyme-linked immunosorbent assays (Human Quantikine MMP-8,-9 ELISA kit). The bone mineral density and bone mineral contents levels were significantly decreased in simulated microgravity condition in both genders, although insignificantly loss was higher in females as compared to males. MMP-8 MMP-9 levels were significantly increased in simulated microgravity as compared to normal condition although insignificantly higher in females as compared to males. Further study is required on large samples size including all factors effecting in simulated microgravity and microgravity. Keys words-Simulated microgravity condition, head-down-tilt, Bone loss, MMP-8, MMP-9, Bone density, Bone mineral contents.

  19. 3D-Printed Scaffolds and Biomaterials: Review of Alveolar Bone Augmentation and Periodontal Regeneration Applications

    Directory of Open Access Journals (Sweden)

    Farah Asa’ad

    2016-01-01

    Full Text Available To ensure a successful dental implant therapy, the presence of adequate vertical and horizontal alveolar bone is fundamental. However, an insufficient amount of alveolar ridge in both dimensions is often encountered in dental practice due to the consequences of oral diseases and tooth loss. Although postextraction socket preservation has been adopted to lessen the need for such invasive approaches, it utilizes bone grafting materials, which have limitations that could negatively affect the quality of bone formation. To overcome the drawbacks of routinely employed grafting materials, bone graft substitutes such as 3D scaffolds have been recently investigated in the dental field. In this review, we highlight different biomaterials suitable for 3D scaffold fabrication, with a focus on “3D-printed” ones as bone graft substitutes that might be convenient for various applications related to implant therapy. We also briefly discuss their possible adoption for periodontal regeneration.

  20. Alveolar bone preservation subsequent to miniscrew implant placement in a canine model

    DEFF Research Database (Denmark)

    Melsen, Birte; Huja, Sarandeep; Chien, Hua-Hong

    2015-01-01

    on the control side. The bone volume within the cylinders was quantified. An insertion of a dental implant was simulated bilaterally at the insertion site. The height of the clinical crown and the alveolar crest were determined on both sides. The bone turnover was assessed histomorphometrically on un...... across the healing alveolar process results in increased density not only adjacent to the screws, but also in the region where a potential dental implant would be inserted. In humans, the insertion of transcortical screws may maintain bone when for various reasons insertion of a permanent dental implant......-decalcified bucco-lingual sections stained with basic fuchsine and toluidine blue. RESULTS: Comparison of the two sides revealed a significant difference both with regard to the bone volume and morphology. The transcortical screw caused an increase in bone density and less ridge atrophy. When simulating a dental...

  1. 3D-Printed Scaffolds and Biomaterials: Review of Alveolar Bone Augmentation and Periodontal Regeneration Applications

    Science.gov (United States)

    Asa'ad, Farah; Giannì, Aldo Bruno; Giannobile, William V.; Rasperini, Giulio

    2016-01-01

    To ensure a successful dental implant therapy, the presence of adequate vertical and horizontal alveolar bone is fundamental. However, an insufficient amount of alveolar ridge in both dimensions is often encountered in dental practice due to the consequences of oral diseases and tooth loss. Although postextraction socket preservation has been adopted to lessen the need for such invasive approaches, it utilizes bone grafting materials, which have limitations that could negatively affect the quality of bone formation. To overcome the drawbacks of routinely employed grafting materials, bone graft substitutes such as 3D scaffolds have been recently investigated in the dental field. In this review, we highlight different biomaterials suitable for 3D scaffold fabrication, with a focus on “3D-printed” ones as bone graft substitutes that might be convenient for various applications related to implant therapy. We also briefly discuss their possible adoption for periodontal regeneration. PMID:27366149

  2. Three-dimensional microstructure of human alveolar trabecular bone: a micro-computed tomography study

    Science.gov (United States)

    2017-01-01

    Purpose The microstructural characteristics of trabecular bone were identified using micro-computed tomography (micro-CT), in order to develop a potential strategy for implant surface improvement to facilitate osseointegration. Methods Alveolar bone specimens from the cadavers of 30 humans were scanned by high-resolution micro-CT and reconstructed. Volumes of interest chosen within the jaw were classified according to Hounsfield units into 4 bone quality categories. Several structural parameters were measured and statistically analyzed. Results Alveolar bone specimens with D1 bone quality had significantly higher values for all structural parameters than the other bone quality categories, except for trabecular thickness (Tb.Th). The percentage of bone volume, trabecular separation (Tb.Sp), and trabecular number (Tb.N) varied significantly among bone quality categories. Tb.Sp varied markedly across the bone quality categories (D1: 0.59±0.22 mm, D4: 1.20±0.48 mm), whereas Tb.Th had similar values (D1: 0.30±0.08 mm, D4: 0.22±0.05 mm). Conclusions Bone quality depended on Tb.Sp and number—that is, endosteal space architecture—rather than bone surface and Tb.Th. Regardless of bone quality, Tb.Th showed little variation. These factors should be taken into account when developing individualized implant surface topographies. PMID:28261521

  3. Combined local application of tetracycline and bisphosphonate reduces alveolar bone resorption in rats.

    Science.gov (United States)

    Yaffe, A; Herman, A; Bahar, H; Binderman, I

    2003-07-01

    Recent animal studies have shown that a combination of chemically-modified tetracyclines together with bisphosphonates, when delivered systemically, are synergistically effective in suppressing periodontal bone loss. In the present study, we explored the combined efficacy of local delivery of alendronate and tetracyclines in reducing alveolar bone loss. Eighty-six (86) male Wistar rats were used in these experiments. The flap was elevated using a special periosteal elevator, on both sides of the mandible, as described previously. A gelfoam pellet containing the drugs was applied between the alveolar bone and the mucoperiosteal flap, according to the experimental protocol. The rats were divided into 5 treatment groups: 1) alendronate; 2) doxycycline hyclate 10% (DOXY); 3) tetracycline hydrochloride 1% (TET); 4) alendronate + DOXY; and 5) alendronate + TET. In the operated control sites (C), saline was applied. The rats were sacrificed 21 days following the flap procedure. Sections of the mandibles (1.5 mm), in a buccal-lingual direction, underwent microradiography and were analyzed for bone loss. DOXY alone was most effective in reducing bone loss. Alendronate was also effective in reducing bone loss as shown in previous reports. TET did not reduce bone loss significantly when used alone. In combination with alendronate TET was synergistically effective. The combined local treatment of alendronate + DOXY showed no additive effect. In the present study, we found that tetracyclines can be most effective in reducing alveolar bone loss when applied locally. The combined local treatment of alendronate and tetracycline may have a synergistic effect.

  4. [Telmisartan effect's on remodelling bone markers in hypertensive patients].

    Science.gov (United States)

    Pérez-Castrillón, J L; De Luis, D; Inglada, L; Olmos Martínez, J M; Pinacho, F; Conde, R; González-Sagrado, M; Dueñas-Laita, A

    2012-01-01

    The telmisartan is an angiotensin II receptor blocker (ARB) with a few own characteristics that it allows us to obtain a few additional benefits. It displays the ability to act as a partial agonist of PPARgamma. On the other hand, PPAR gamma intervenes in the control of bone remodelling though with not concordant results. The objective of this study to value the effect of telmisartan on bone markers in hypertensive patients. A sample of 31 hypertensive patients with hypertension were included. The dose of telmisartan was of 80 mg/24 h and the period of follow-up was 12 weeks. The control group included 32 hypertensive patients treated before with IECA (enalapril-20 mg/24 h - or quinapril - 40 mg/24 hours). The following parameters were determined P1NP, β-CTX, 25OHD and PTH , osteocalcin, insulin and adiponectin. The patients treated with Telmisartan shown a significantly decrease in systolic blood pressure (156 ± 19 mmHg vs 133 ± 15 mmHg, p = 0.001) and diastolic blood pressure (92 ± 9 mmHg vs 82 ± 6 mmHg, p = 0.01) . Changes were not observed in other parameter, PTHi (48 ± 22 pg/ml vs 45 ± 22 pg/ml, p > 0.05) and 25-vitamin D (21 ± 10 ng/ml vs 25 ± 8 ng/ml, p > 0.05), CTX (0.195 ± 0.12 ng/ml vs 0.221 ± 0.13 ng/ml, p > 0.05), PINP (39 ± 20 ng/ml vs 40 ± 19 ng/ml, p > 0.05), osteocalcin (11 ± 9 ng/ml vs 11 ± 5 ng/ml, p > 0.05), glucose, adiponectin, insulin and HOMA. When the patients divided in two groups depending on the levels of vitamin D (insufficient and not insufficient), with a cut of 20 ng/ml, there was changes on bone markers but a decrease of the glucose was observed in patients with levels of vitamin D over 20 ng/ml (135 ± 53 mg/dl vs 119 ± 39 mg/dl, p = 0.01). The patients treated with IECAS decreases the systolic blood pressure but the diastolic blood pressure values of arterial systolic does not show changes. Telmisartan has a neutral effect to level of the bone markers of bone remodelling.

  5. CBX7 deficiency plays a positive role in dentin and alveolar bone development.

    Science.gov (United States)

    Zhou, Zhixuan; Yin, Ying; Jiang, Fei; Niu, Yuming; Wan, Shujian; Chen, Ning; Shen, Ming

    2016-08-01

    To clarify the role of CBX7 deficiency in dentin and alveolar bone development, the dental and mandibular phenotypes of homozygous CBX7-knockout (CBX7(-/-)) mice were compared with their wild-type (WT) counterparts at 3 weeks age. In contrast to WT littermates, dental volume and dentin sialoprotein-positive area were significantly increased, whereas the area ratio of predentin to dentin was decreased markedly in CBX7(-/-) mice. Mineral density, cortical thickness, alveolar bone volume, type I collagen and osterix-immunopositive area, osteoblast number and activity, protein expression and mRNA level of Runt-related transcription factor 2 (Runx2), alkaline phosphatase, osteocalcin, osteopontin and bone morphogenetic protein 2 (BMP2) were all remarkably increased, while osteoclast number and activity, and mRNA expression ratio of NF-κB ligand (RANKL) to osteoprotegerin (opg) were all decreased significantly in the alveolar bone of CBX7(-/-) mice compared with their WT counterparts. Moreover, proliferating cell nuclear antigen (PCNA)-positive cells were found more in Hertwig' s epithelial root sheath of CBX7(-/-) mice, and their protein level of cyclin E1, cyclin-dependent kinase 2 (CDK2) were correspondingly increased in contrast to WT mice. Taken together, these results of this study suggest that CBX7 deficiency plays a positive role in dentin and alveolar bone formation.

  6. Effects of simvastatin gel on bone regeneration in alveolar defects in miniature pigs

    Institute of Scientific and Technical Information of China (English)

    CHEN Shan; YANG Jun-ying; ZHANG Sheng-yan; FENG Lei; REN Jing

    2011-01-01

    Background Currently,the most commonly used treatment methods for repairing alveolar furcation defects are periodontal guided tissue regeneration (GTR) and bone grafting.The objective of this study was to investigate the effects of simvastatin/methylcellulose gel on bone regeneration in alveolar defects in miniature pigs.Methods Alveolar defects were produced in 32 teeth (the third and fourth premolars) of 4 miniature pigs.The 32 experimental teeth were divided into 5 groups comprising control (C) and treatment (T) teeth:(1) empty defects without gel (group C0,n=4); (2) defects injected with methylcellulose gel (group C1,n=4); (3) defects injected with 0.5 mg/50 μl simvastatin/methylcellulose gel (group T1,n=8); (4) defects injected with 1.5 mg/50 μl simvastatin/methylcellulose gel (group T2,n=8); and (5) defects injected with 2.2 mg/50 μl simvastatin/methylcellulose gel (group T3,n=8).Every week after surgery,the furcation sites were injected once with gel.At the eighth week after surgery,the 4 pigs were sacrificed and underwent macroscopic observation,descriptive histologic examination,and regenerate bone quantitative histologic examination.Results At 8 weeks after surgery,the defect sites in the treatment groups were completely filled in with new bone and fibrous tissue.There was little new bone in the C0 and C1 groups,and only a small number of osteoblasts and proliferative vessels could be seen on microscopic examination.Conclusions Miniature pigs are an ideal experimental animal for establishing a model of alveolar defects using a surgical method.Local application of simvastatin/methylcellulose gel can stimulate the regeneration of alveolar bone in furcation defect sites,because it promotes the proliferation of osteoblasts.The best dose of simvastatin gel to stimulate bone regeneration is 0.5 mg.

  7. Orthodontically guided bone transport in the treatment of alveolar cleft: A case report

    Science.gov (United States)

    Gómez, Elena; Otero, Marta; Berraquero, Rosario; Wucherpfennig, Begona; Hernández-Godoy, Juan; Guiñales, Jorge; Vincent, Germán; Burgueño, Miguel

    2016-01-01

    Introduction Conventional treatments are sometimes not possible in certain alveolar cleft cases due to the severity of the gap which separates the fragments. Various management strategies have been proposed, including sequential surgical interventions or delaying treatment until adulthood to then carry out maxillary osteotomies. A further alternative approach has also been proposed, involving the application of bone transport techniques to mobilise the osseous fragments and thereby reduce the gap between lateral fragments and the premaxilla. Case Report We introduce the case of a 10-year-old patient who presented with a bilateral alveolar cleft and a severe gap. Stable occlusion between the premaxilla and the mandible was achieved following orthodontic treatment, making it inadvisable to perform a retrusive osteotomy of the premaxilla in order to close the alveolar clefts. Faced with this situation, it was decided we would employ a bone transport technique under orthodontic guidance using a dental splint. This would enable an osseous disc to be displaced towards the medial area and reduce the interfragmentary distance. During a second surgical intervention, closure of the soft tissues was performed and the gap was filled in using autogenous bone. Conclusions The use of bone transport techniques in selected cases allows closure of the osseous defect, whilst also preserving soft tissues and reducing the amount of bone autograft required. In our case, we were able to respect the position of the premaxilla and, at the same time, generate new tissues at both an alveolar bone and soft tissue level with results which have remained stable over the course of time. Key words:Alveolar cleft, bone transport, graft. PMID:26855699

  8. Effects of implant drilling parameters for pilot and twist drills on temperature rise in bone analog and alveolar bones.

    Science.gov (United States)

    Chen, Yung-Chuan; Hsiao, Chih-Kun; Ciou, Ji-Sih; Tsai, Yi-Jung; Tu, Yuan-Kun

    2016-11-01

    This study concerns the effects of different drilling parameters of pilot drills and twist drills on the temperature rise of alveolar bones during dental implant procedures. The drilling parameters studied here include the feed rate and rotation speed of the drill. The bone temperature distribution was analyzed through experiments and numerical simulations of the drilling process. In this study, a three dimensional (3D) elasto-plastic dynamic finite element model (DFEM) was proposed to investigate the effects of drilling parameters on the bone temperature rise. In addition, the FE model is validated with drilling experiments on artificial human bones and porcine alveolar bones. The results indicate that 3D DFEM can effectively simulate the bone temperature rise during the drilling process. During the drilling process with pilot drills or twist drills, the maximum bone temperature occurred in the region of the cancellous bones close to the cortical bones. The feed rate was one of the important factors affecting the time when the maximum bone temperature occurred. Our results also demonstrate that the elevation of bone temperature was reduced as the feed rate increased and the drill speed decreased, which also effectively reduced the risk region of osteonecrosis. These findings can serve as a reference for dentists in choosing drilling parameters for dental implant surgeries.

  9. Meshless methods in biomechanics bone tissue remodelling analysis

    CERN Document Server

    Belinha, Jorge

    2014-01-01

    This book presents the complete formulation of a new advanced discretization meshless technique: the Natural Neighbour Radial Point Interpolation Method (NNRPIM). In addition, two of the most popular meshless methods, the EFGM and the RPIM, are fully presented. Being a truly meshless method, the major advantages of the NNRPIM over the FEM, and other meshless methods, are the remeshing flexibility and the higher accuracy of the obtained variable field. Using the natural neighbour concept, the NNRPIM permits to determine organically the influence-domain, resembling the cellulae natural behaviour. This innovation permits the analysis of convex boundaries and extremely irregular meshes, which is an advantage in the biomechanical analysis, with no extra computational effort associated.   This volume shows how to extend the NNRPIM to the bone tissue remodelling analysis, expecting to contribute with new numerical tools and strategies in order to permit a more efficient numerical biomechanical analysis.

  10. 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.

  11. Alcoholic and isocaloric diet, but not ovariectomy, influence the apoptosis of bone cells within the alveolar bone crest of rats.

    Science.gov (United States)

    Marchini, Adriana Mathias Pereira da Silva; Gonçalves, Lucélia Lemes; Salgado, Miriane Carneiro Machado; do Prado, Renata Falchete; Marchini, Leonardo; Carvalho, Yasmin Rodarte; da Rocha, Rosilene Fernandes

    2014-04-01

    Studies suggest that chronic alcoholism as well as oestrogen deficiencies may affect bones in general, including alveolar bone and, by doing so, increase individuals' susceptibility to develop progressive periodontal disease. This paper aims to verify the influence of chronic alcoholism and/or oestrogen deficiencies in the apoptosis of bone cells of the alveolar bone crest region in rats. Initially, 54 rats were divided into ovariectomized (Ovx) and Sham operated (Sham) groups. Thirty days after surgery, these two groups were equally sub-divided, and received, for 56 days, the following dietary intervention: alcoholic diet (with 20% alcohol solution,), isocaloric diet and ad libitum diet (free diet). Analysis was undertaken by immunohistochemistry, using an antibody to detect apoptosis (anti PARP p-85). When comparing the six experimental groups, no significant differences were observed in the apoptosis of bone cells. Also, there was no significant difference in the quantity of cells undergoing apoptosis when the animals from Ovx groups were compared with those from Sham groups. However, when comparing only different dietary groups, differences were observed between the groups ad libitum and isocaloric, to osteoblasts (p=0.045); and ad libitum and alcohol, to osteocytes (p=0.007). It is concluded that ovariectomy was not able to influence the rate of apoptosis of bone cells of the alveolar bone crest region in rats and that a possible influence of diet on apoptosis of osteoblasts and osteocytes cannot be ruled out. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Nardosinone Suppresses RANKL-Induced Osteoclastogenesis and Attenuates Lipopolysaccharide-Induced Alveolar Bone Resorption

    Science.gov (United States)

    Niu, Chenguang; Xiao, Fei; Yuan, Keyong; Hu, XuChen; Lin, Wenzhen; Ma, Rui; Zhang, Xiaoling; Huang, Zhengwei

    2017-01-01

    Periodontitis is a chronic inflammatory disease that damages the integrity of the tooth-supporting tissues, known as the periodontium, and comprising the gingiva, periodontal ligament and alveolar bone. In this study, the effects of nardosinone (Nd) on bone were tested in a model of lipopolysaccharide (LPS)-induced alveolar bone loss, and the associated mechanisms were elucidated. Nd effectively suppressed LPS-induced alveolar bone loss and reduced osteoclast (OC) numbers in vivo. Nd suppressed receptor activator of nuclear factor-κB ligand (RANKL)-mediated OC differentiation, bone resorption, and F-actin ring formation in a dose-dependent manner. Further investigation revealed that Nd suppressed osteoclastogenesis by suppressing the ERK and JNK signaling pathways, scavenging reactive oxygen species, and suppressing the activation of PLCγ2 that consequently affects the expression and/or activity of the OC-specific transcription factors, c-Fos and nuclear factor of activated T-cells cytoplasmic 1 (NFATc1). In addition, Nd significantly reduced the expression of OC-specific markers in mouse bone marrow-derived pre-OCs, including c-Fos, cathepsin K (Ctsk), VATPase d2, and Nfatc1. Collectively, these findings suggest that Nd has beneficial effects on bone, and the suppression of OC number implies that the effect is exerted directly on osteoclastogenesis. PMID:28955231

  13. Comparison of the buccolingual inclination in alveolar bone and tooth using dental CBCT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Eun; Kim, Jin Soo; Kim, Jae Duk [Chosun University, Gwangju (Korea, Republic of)

    2008-03-15

    It is important to determine the bucco-lingual inclination of implants on radiographs before the implant surgery. The purpose of this study was to compare the buccolingual inclination in alveolar bone and the tooth with dental cone beam CT and to prepare the standard for the buccolingual inclination of implant. Axial, panoramic, and buccolingually sectioned images of 80 implant cases with stent including straight marker using CB Mercuray{sup TM} (Hitachi, Japan) were evaluated. The comparison of the buccolingual inclination of remained alveolar bone with the tooth and the marker on buccolingually sectioned views was performed statistically. The average buccolingual inclination of remained alveolar bone and tooth was 82.8 {+-} 4.6 .deg. C and 85.8 {+-} 4.7 .deg. C (p<0.05, r=0.96) at the 1st molar area and 76.4 {+-} 1.7 .deg. C and 82.7 {+-} 1.7 .deg. C respectively (p>0.05, r=0.12) at the 2nd premolar area in upper jaw. The average buccolingual inclination of remained alveolar bone and tooth was 81.3 {+-} 8.3 .deg. C and 87.5 {+-} 6.3 .deg. C (p>0.05, r=0.85) at the lower 2nd premolar area and 94.3 {+-} 6.6 .deg. C and 93.3 {+-} 7.2 .deg. C respectively (p>0.05, r=0.91) at the 1st molar area in lower jaw. The inclinations of markers were very different from those of remained bone at the most of areas except the upper 2nd premolar area (r=0.79). We recommend dental CBCT analysis for determining the buccolingual inclination of dental implant, because of significant difference, in average, between the buccolingual inclination of remained alveolar bone and tooth.

  14. In vitro culture and characterization of alveolar bone osteoblasts isolated from type 2 diabetics

    Directory of Open Access Journals (Sweden)

    Dao-Cai Sun

    2012-06-01

    Full Text Available In order to understand the mechanisms of poor osseointegration following dental implants in type 2 diabetics, it is important to study the biological properties of alveolar bone osteoblasts isolated from these patients. We collected alveolar bone chips under aseptic conditions and cultured them in vitro using the tissue explants adherent method. The biological properties of these cells were characterized using the following methods: alkaline phosphatase (ALP chemical staining for cell viability, Alizarin red staining for osteogenic characteristics, MTT test for cell proliferation, enzyme dynamics for ALP contents, radio-immunoassay for bone gla protein (BGP concentration, and ELISA for the concentration of type I collagen (COL-I in the supernatant. Furthermore, we detected the adhesion ability of two types of cells from titanium slices using non-specific immunofluorescence staining and cell count. The two cell forms showed no significant difference in morphology under the same culture conditions. However, the alveolar bone osteoblasts received from type 2 diabetic patients had slower growth, lower cell activity and calcium nodule formation than the normal ones. The concentration of ALP, BGP and COL-I was lower in the supernatant of alveolar bone osteoblasts received from type 2 diabetic patients than in that received from normal subjects (P < 0.05. The alveolar bone osteoblasts obtained from type 2 diabetic patients can be successfully cultured in vitro with the same morphology and biological characteristics as those from normal patients, but with slower growth and lower concentration of specific secretion and lower combining ability with titanium than normal ones.

  15. 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.

  16. Decoronation of an ankylosed tooth for preservation of alveolar bone prior to implant placement.

    Science.gov (United States)

    Filippi, A; Pohl, Y; von Arx, T

    2001-04-01

    A 12-year-old patient sustained avulsions of both permanent maxillary central incisors. Subsequently, both teeth developed replacement resorption. The left incisor was extracted alio loco. The right incisor was treated by decoronation (removal of crown and pulp, but preservation of the root substance). Comparison of both sites demonstrated complete preservation of the height and width of the alveolar bone at the decoronation site, whereas the tooth extraction site showed considerable bone loss. In addition, some vertical bone apposition was found on top of the decoronated root. Decoronation is a simple and safe surgical procedure for preservation of alveolar bone prior to implant placement. It must be considered as a treatment option for teeth affected by replacement resorption if tooth transplantation is not feasible.

  17. Congenital Bone Fractures in Spinal Muscular Atrophy: Functional Role for SMN Protein in Bone Remodeling

    Science.gov (United States)

    Shanmugarajan, Srinivasan; Swoboda, Kathryn J.; Iannaccone, Susan T.; Ries, William L.; Maria, Bernard L.; Reddy, Sakamuri V.

    2009-01-01

    Spinal muscular atrophy is the second most common fatal childhood disorder. Core clinical features include muscle weakness caused by degenerating lower motor neurons and a high incidence of bone fractures and hypercalcemia. Fractures further compromise quality of life by progression of joint contractures or additional loss of motor function. Recent observations suggest that bone disease in spinal muscular atrophy may not be attributed entirely to lower motor neuron degeneration. The presence of the spinal muscular atrophy disease-determining survival motor neuron gene (SMN), SMN expression, and differential splicing in bone-resorbing osteoclasts was recently discovered. Its ubiquitous expression and the differential expression of splice variants suggest that SMN has specific roles in bone cell function. SMN protein also interacts with osteoclast stimulatory factor. Mouse models of human spinal muscular atrophy disease suggest a potential role of SMN protein in skeletal development. Dual energy x-ray absorptiometry analysis demonstrated a substantial decrease in total bone area and poorly developed caudal vertebra in the mouse model. These mice also had pelvic bone fractures. Studies delineating SMN signaling mechanisms and gene transcription in a cell-specific manner will provide important molecular insights into the pathogenesis of bone disease in children with spinal muscular atrophy. Moreover, understanding bone remodeling in spinal muscular atrophy may lead to novel therapeutic approaches to enhance skeletal health and quality of life. This article reviews the skeletal complications associated with spinal muscular atrophy and describes a functional role for SMN protein in osteoclast development and bone resorption activity. PMID:17761651

  18. 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

  19. Validation of a dental image analyzer tool to measure alveolar bone loss in periodontitis patients

    NARCIS (Netherlands)

    Teeuw, W.J.; Coelho, L.; de Silva, A.; van der Palen, C.J.N.M.; Lessmann, F.G.J.M.; van der Velden, U.; Loos, B.G.

    2009-01-01

    Background and Objective:  Radiographs are an essential adjunct to the clinical examination for periodontal diagnoses. Over the past few years, digital radiographs have become available for use in clinical practice. Therefore, the present study investigated whether measuring alveolar bone loss, usin

  20. B Cell IgD Deletion Prevents Alveolar Bone Loss Following Murine Oral Infection

    Directory of Open Access Journals (Sweden)

    Pamela J. Baker

    2009-01-01

    and CD4+ T cells in immune normal mice compared to IgD deficient mice. These data suggest that IgD is an important mediator of alveolar bone resorption, possibly through antigen-specific coactivation of B cells and CD4+ T cells.

  1. Validation of a dental image analyzer tool to measure alveolar bone loss in periodontitis patients

    NARCIS (Netherlands)

    Teeuw, W.J.; Coelho, L.; de Silva, A.; van der Palen, C.J.N.M.; Lessmann, F.G.J.M.; van der Velden, U.; Loos, B.G.

    2009-01-01

    Background and Objective:  Radiographs are an essential adjunct to the clinical examination for periodontal diagnoses. Over the past few years, digital radiographs have become available for use in clinical practice. Therefore, the present study investigated whether measuring alveolar bone loss, usin

  2. Hounsfield Unit Change in Root and Alveolar Bone during Canine Retraction

    Science.gov (United States)

    Jiang, Feifei; Liu, Sean Y.; Xia, Zeyang; Li, Shuning; Chen, Jie; Kula, Katherine S.; Eckert, George

    2014-01-01

    Objectives The objective of this study was to determine the Hounsfield unit (HU) changes in the alveolar bone and root surface during controlled canine retractions. Methods Eighteen maxillary canine retraction patients were selected for this split mouth design clinical trial. The canines in each patient were randomly assigned to receive either translation or controlled tipping treatment strategy. Pre- and post-treatment cone beam computed tomography scans of each patient were used to determine tooth movement direction and HU changes. The alveolar bone and root surface were divided into 108 divisions, respectively. The HU in each division was measured. The Mixed-model ANOVA was applied to test the HU change distribution at the p<0.05 significant level. Results The HU changes varied with the directions relative to the canine movement. The HU reduction occurred at the root surface. Larger reductions occurred in the divisions that were perpendicular to the moving direction. However, HU decreased in the alveolar bone in the moving direction. The highest HU reduction was at the coronal level. Conclusions HU reduction occurs on the root surface in the direction perpendicular to the tooth movement and in the alveolar bone in the direction of tooth movement when a canine is retracted. PMID:25836004

  3. Development and characterization of a rabbit alveolar bone nonhealing defect model.

    NARCIS (Netherlands)

    Young, S.; Bashoura, A.G.; Borden, T.; Baggett, L.S.; Jansen, J.A.; Wong, M.; Mikos, A.G.

    2008-01-01

    The aim of this study was to develop an easily accessible and reproducible, nonhealing alveolar bone defect in the rabbit mandible. Twenty-four adult male New Zealand white rabbits underwent unilateral mandibular defect surgery. Two types of defect in the premolar/molar region were compared: (1) a 1

  4. Use of Three-Dimensional Computed Tomography to Classify Filling of Alveolar Bone Grafting

    Directory of Open Access Journals (Sweden)

    Antonio Jorge V. Forte

    2012-01-01

    Full Text Available Several authors have proposed classifications to analyze the quality over time of secondary alveolar bone grafting. However, little discussion has been held to quantitatively measure the secondary bone grafting for correction of nasal deformity associated to cleft palate and lip. Twenty patients with unilateral alveolar cleft, who underwent secondary alveolar bone grafting, were studied with 3D computer tomography. The height between the inferior portion of the pyriform aperture and the incisal border of the unaffected side (height A and the affected side (height B was measured using a software Mirror. A percentage was then obtained dividing the height B by the height A and classified into grades I, II, and III if the value was greater than 67%, between 34% and 66%, or less than 33%. Age, time of followup, initial operation, and age of canine eruption were also recorded. All patients presented appropriate occlusion and function. Mean time of followup was 7 years, and mean initial age for operation was 10 years old. 16 patients were rated as grade I and 4 patients as grade II. No cases had grade III. We present a new grading system that can be used to assess the success of secondary bone grafting in patients who underwent alveolar cleft repair.

  5. 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.

  6. Determinants of ovine compact bone viscoelastic properties: effects of architecture, mineralization, and remodeling.

    Science.gov (United States)

    Les, C M; Spence, C A; Vance, J L; Christopherson, G T; Patel, B; Turner, A S; Divine, G W; Fyhrie, D P

    2004-09-01

    Significant decreases in ovine compact bone viscoelastic properties (specifically, stress-rate sensitivity, and damping efficiency) are associated with three years of ovariectomy and are particularly evident at higher frequencies [Proc. Orthop. Res. Soc. 27 (2002) 89]. It is unclear what materials or architectural features of bone are responsible for either the viscoelastic properties themselves, or for the changes in those properties that were observed with estrogen depletion. In this study, we examined the relationship between these viscoelastic mechanical properties and features involving bone architecture (BV/TV), materials parameters (ash density, %mineralization), and histologic evidence of remodeling (%remodeled, cement line interface). The extent of mineralization was inversely proportional to the material's efficiency in damping stress oscillations. The damping characteristics of bone material from ovariectomized animals were significantly more sensitive to variation in mineralization than was bone from control animals. At low frequencies (6 Hz or less), increased histologic evidence of remodeling was positively correlated with increased damping efficiency. However, the dramatic decreases in stress-rate sensitivity that accompanied 3-year ovariectomy were seen throughout the bone structure and occurred even in areas with little or no secondary Haversian remodeling as well as in areas of complete remodeling. Taken together, these data suggest that, while the mineral component may modify the viscoelastic behavior of bone, the basic mechanism underlying bone viscoelastic behavior, and of the changes in that behavior with estrogen depletion, reside in a non-mineral component of the bone that can be significantly altered in the absence of secondary remodeling.

  7. The effects of replacing collagen fibers with carbon nanotubes on the rate of bone remodeling process.

    Science.gov (United States)

    Jamilpour, Nima; Fereidoon, Abdolhosein; Rouhi, Gholamreza

    2011-08-01

    Application of carbon nanotubes (CNTs) instead of collagen fibers (CFs) in bone tissue is one of the proposed avenues for the enhancement of bone's mechanical properties. The mechanical behavior improvement caused by such a replacement is somehow guaranteed because of the superior mechanical properties of CNTs compared to those of CFs. But on the other side, bone is a very active and dynamic tissue, which is maintained through a lifelong coupled process of resorption and formation in order to reach an optimal configuration. Hence, the well accepted fact of the bone remodeling dependency on mechanical stimuli besides the differences in mechanical behavior of CNTs and CFs under loading can encourage one to hypothesize that such a replacement would cause an imbalance in the normal rate of bone remodeling process. Results of our finite element analysis indicate that the application of CNTs instead of CFs can cause a significant reduction in strain energy density, assumed here as the mechanical stimulus to initiate the bone remodeling process. Our results also show that this replacement may change the strain energy distribution within the bone. Based on a semi-mechanistic bone remodeling theory, it is speculated that this alteration in strain energy distribution in artificial bone can destabilize normal bone remodeling process, and therefore it is likely to cause some abnormalities in bone's mechanical and biological functions.

  8. Correlation analysis of alveolar bone loss in buccal/palatal and proximal surfaces in rats

    Directory of Open Access Journals (Sweden)

    Carolina Barrera de Azambuja

    2012-12-01

    Full Text Available The aim was to correlate alveolar bone loss in the buccal/palatal and the mesial/distal surfaces of upper molars in rats. Thirty-three, 60-day-old, male Wistar rats were divided in two groups, one treated with alcohol and the other not treated with alcohol. All rats received silk ligatures on the right upper second molars for 4 weeks. The rats were then euthanized and their maxillae were split and defleshed with sodium hypochlorite (9%. The cemento-enamel junction (CEJ was stained with 1% methylene blue and the alveolar bone loss in the buccal/palatal surfaces was measured linearly in 5 points on standardized digital photographs. Measurement of the proximal sites was performed by sectioning the hemimaxillae, restaining the CEJ and measuring the alveolar bone loss linearly in 3 points. A calibrated and blinded examiner performed all the measurements. Intraclass Correlation Coefficient revealed values of 0.96 and 0.89 for buccal/lingual and proximal surfaces, respectively. The Pearson Correlation Coefficient (r between measurements in buccal/palatal and proximal surfaces was 0.35 and 0.05 for the group treated with alcohol, with and without ligatures, respectively. The best correlations between buccal/palatal and proximal surfaces were observed in animals not treated with alcohol, in sites both with and without ligatures (r = 0.59 and 0.65, respectively. A positive correlation was found between alveolar bone loss in buccal/palatal and proximal surfaces. The correlation is stronger in animals that were not treated with alcohol, in sites without ligatures. Areas with and without ligature-induced periodontal destruction allow detection of alveolar bone loss in buccal/palatal and proximal surfaces.

  9. Adaptive Bone Remodeling of the Femoral Bone After Tumor Resection Arthroplasty With an Uncemented Proximally Hydroxyapatite-Coated Stem

    DEFF Research Database (Denmark)

    Andersen, Mikkel R; Petersen, Michael M

    2015-01-01

    Loss of bone stock and stress shielding is a significant challenge in limb salvage surgery. This study investigates the adaptive bone remodeling of the femoral bone after implantation of a tumor prosthesis with an uncemented press fit stem. We performed a prospective 1 yr follow-up of 6 patients ...

  10. Intracortical bone remodeling variation shows strong genetic effects.

    Science.gov (United States)

    Havill, L M; Allen, M R; Harris, J A K; Levine, S M; Coan, H B; Mahaney, M C; Nicolella, D P

    2013-11-01

    Intracortical microstructure influences crack propagation and arrest within bone cortex. Genetic variation in intracortical remodeling may contribute to mechanical integrity and, therefore, fracture risk. Our aim was to determine the degree to which normal population-level variation in intracortical microstructure is due to genetic variation. We examined right femurs from 101 baboons (74 females, 27 males; aged 7-33 years) from a single, extended pedigree to determine osteon number, osteon area (On.Ar), haversian canal area, osteon population density, percent osteonal bone (%On.B), wall thickness (W.Th), and cortical porosity (Ct.Po). Through evaluation of the covariance in intracortical properties between pairs of relatives, we quantified the contribution of additive genetic effects (heritability [h (2)]) to variation in these traits using a variance decomposition approach. Significant age and sex effects account for 9 % (Ct.Po) to 21 % (W.Th) of intracortical microstructural variation. After accounting for age and sex, significant genetic effects are evident for On.Ar (h (2) = 0.79, p = 0.002), %On.B (h (2) = 0.82, p = 0.003), and W.Th (h (2) = 0.61, p = 0.013), indicating that 61-82 % of the residual variation (after accounting for age and sex effects) is due to additive genetic effects. This corresponds to 48-75 % of the total phenotypic variance. Our results demonstrate that normal, population-level variation in cortical microstructure is significantly influenced by genes. As a critical mediator of crack behavior in bone cortex, intracortical microstructural variation provides another mechanism through which genetic variation may affect fracture risk.

  11. Analogy of strain energy density based bone-remodeling algorithm and structural topology optimization.

    Science.gov (United States)

    Jang, In Gwun; Kim, Il Yong; Kwak, Byung Ban

    2009-01-01

    In bone-remodeling studies, it is believed that the morphology of bone is affected by its internal mechanical loads. From the 1970s, high computing power enabled quantitative studies in the simulation of bone remodeling or bone adaptation. Among them, Huiskes et al. (1987, "Adaptive Bone Remodeling Theory Applied to Prosthetic Design Analysis," J. Biomech. Eng., 20, pp. 1135-1150) proposed a strain energy density based approach to bone remodeling and used the apparent density for the characterization of internal bone morphology. The fundamental idea was that bone density would increase when strain (or strain energy density) is higher than a certain value and bone resorption would occur when the strain (or strain energy density) quantities are lower than the threshold. Several advanced algorithms were developed based on these studies in an attempt to more accurately simulate physiological bone-remodeling processes. As another approach, topology optimization originally devised in structural optimization has been also used in the computational simulation of the bone-remodeling process. The topology optimization method systematically and iteratively distributes material in a design domain, determining an optimal structure that minimizes an objective function. In this paper, we compared two seemingly different approaches in different fields-the strain energy density based bone-remodeling algorithm (biomechanical approach) and the compliance based structural topology optimization method (mechanical approach)-in terms of mathematical formulations, numerical difficulties, and behavior of their numerical solutions. Two numerical case studies were conducted to demonstrate their similarity and difference, and then the solution convergences were discussed quantitatively.

  12. 双维控制牙槽骨牵张器的成骨效应%A bidirectional alveolar bone distraction device for osteogenesis of alveolar bone

    Institute of Scientific and Technical Information of China (English)

    黄代营; 聂二民; 孙明; 黎炽彬

    2011-01-01

    背景:牵张成骨增高牙槽嵴在基础研究及临床已有很多成功报道,双维控制垂直牙槽骨牵张器可有效防止单向直线牵张器行牙槽骨牵张发生轴向移位.目的:研制双维控制的牙槽骨牵张器,并通过动物实验观察其成骨效应.方法:选择杂种犬4只,拔除一侧下颌前磨牙形成萎缩牙槽骨模型.1个月后行骨切开放置双维牵张器,7 d后垂直牵张 (1 mm/d,共5 d).完成垂直牵张后,利用双维牵张器颊向控制功能将移动骨块颊向牵出(大约2.4 mm),固定2个月后行大体观察及组织学检查.结果与结论:4只犬中2只黏膜伤口愈合良好,2只黏膜出现裂开,行二次缝合后愈合,牵张器固位良好,未出现松动、脱落.牵张骨块向垂直向及颊向的位移量满足实验目的要求,牙槽骨垂直向高度平均增加(5.0±0.2) mm,颊向宽度平均增加(2.4±0.3) mm.大体观察及组织学检查均证实牵张成骨的骨块新骨形成良好.说明双维控制垂直牙槽骨牵张器能较好的控制移动骨块垂直或颊向的移动方向,并且新骨形成良好.%BACKGROUND: Alveolar bone augmentation using a unidirectional dist raction device may lead to axial displacement. Abidirectional distraction device can control the vertical and buccal-lingual directions. But studies regarding this have been rarelyreported.OBJECTIVE: To develop a bidirectional alveolar bone distraction device and to investigate its effects on osteogenic effectsthrough an animal experiment.METHODS: Four adult mongrel dogs were established into models of alveolar bone atrophy by extraction of unilateral mandiblepremolars. After 1 month, alveolar bone was cut open and a bilateral distraction device was placed. Seven days later, thedistraction was started at a rate of 1 mm/day for 5 days. At last, buccal-lingual direction distraction (approximately 2.4 mm) wastaken for once, followed by a consolidation period of 2 months. Subsequently, gross observation and

  13. Digital radiographic evaluation of alveolar bone loss, density and lamina dura integrity on post splinting mandibular anterior with chronic periodontitis

    Science.gov (United States)

    Rafini, F.; Priaminiarti, M.; Sukardi, I.; Lessang, R.

    2017-08-01

    The healing of periodontal splinting can be detected both with clinical and radiographic examination. In this study, the alveolar bone was evaluated by radiographic digital periapical analysis. Periodontal tooth splinting is periodontal support therapy used to prevent periodontal injury during repair and regeneration of periodontal therapy. Radiographic digital periapical analysis of alveolar bone in the mandibular anterior region with chronic periodontitis and 2/3 cervical bone loss after three months of periodontal splinting. Eighty four proximal site (43 mesial and 41 distal) from 16 patients with chronic periodontitis and treated with spinting were examined by taking periapical digital radiographic at day 1 and 91. The bone loss, bone density and utility of lamina dura were evaluated. The statistical analysis after three months evaluation using T-test for bone loss, Wilcoxon sign rank test for bone density and utility lamina dura showed no significantly differences (pperiodontitis with 2/3 alveolar bone loss after three months splinting.

  14. The Digital Astronaut Project Computational Bone Remodeling Model (Beta Version) Bone Summit Summary Report

    Science.gov (United States)

    Pennline, James; Mulugeta, Lealem

    2013-01-01

    changes in bone cell populations that remove and replace bone in packets within the bone region. The DAP bone model is unique in several respects. In particular in takes former models of volume fraction changes one step higher in fidelity and separates BVF into separate equations for mineralized and osteoid volume fractions governed by a mineralization rate. This more closely follows the physiology of the remodeling unit cycles where bone is first resorbed and then followed by the action of osteoblasts to lay down collagen matrix which eventually becomes mineralized. In another respect, the modules allow the functional description of the time rate of change of other parameters and variables in the model during a computational simulation. More detailed description of the model, preliminary validation results, current limitation and caveats, and planned advancements are provided in sections 2 through 5. The DAP bone model is being developed primarily as a research tool, and not as a clinical tool like QCT. Even if it transitions to a clinical tool, it is not intended to replace QCT or any other clinical tool. Moreover, the DAP bone model does not predict bone fracture. Its purpose is to provide valuable additional data via "forward prediction" simulations for during and after spaceflight missions to gain insight on, (1) mechanisms of bone demineralization in microgravity, and (2) the volumetric changes at the various bone sites in response to in-flight and post-flight exercise countermeasures. This data can then be used as input to the Keyak [8] (or equivalent) FE analysis method to gain insight on how bone strength may change during and after flight. This information can also be useful to help optimize exercise countermeasure protocols to minimize changes in bone strength during flight, and improve regain of bone strength post-flight. To achieve this goal, the bone model will be integrated with DAP's exercise countermeasure models to simulate the effect of exercise

  15. Biodegradable effect of PLGA membrane in alveolar bone regeneration on beagle dog.

    Science.gov (United States)

    Hua, Nan; Ti, Vivian Lao; Xu, Yuanzhi

    2014-11-01

    Guided bone regeneration (GBR) is a principle adopted from guided tissue regeneration (GTR). Wherein, GBR is used for the healing of peri-implant bony dehiscences, for the immediate placement of implants into extraction sockets and for the augmentation of atrophic alveolar ridges. This procedure is done by the placement of a resorbable or non-resorbable membrane that will exclude undesirable types of tissue growth between the extraction socket and the soft tissue to allow only bone cells to regenerate in the surgically treated lesion. Here, we investigated the biodegradable effect of polylactic-co-glycolic acid (PLGA) membrane in the alveolar bone on Beagle dogs. Results show that both collagen and PLGA membrane had been fully resorbed, biodegraded, at four weeks post-operative reentry into the alveolar bone. Histological results under light microscopy revealed formation of new bone trabeculae in the extraction sites on both collagen and PLGA membrane. In conclusion, PLGA membrane could be a potential biomaterials for use on GBR and GTR. Nevertheless, further studies will be necessary to elucidate the efficiency and cost effectiveness of PLGA as GBR membrane in clinical.

  16. Fusobacterium nucleatum and Tannerella forsythia induce synergistic alveolar bone loss in a mouse periodontitis model.

    Science.gov (United States)

    Settem, Rajendra P; El-Hassan, Ahmed Taher; Honma, Kiyonobu; Stafford, Graham P; Sharma, Ashu

    2012-07-01

    Tannerella forsythia is strongly associated with chronic periodontitis, an inflammatory disease of the tooth-supporting tissues, leading to tooth loss. Fusobacterium nucleatum, an opportunistic pathogen, is thought to promote dental plaque formation by serving as a bridge bacterium between early- and late-colonizing species of the oral cavity. Previous studies have shown that F. nucleatum species synergize with T. forsythia during biofilm formation and pathogenesis. In the present study, we showed that coinfection of F. nucleatum and T. forsythia is more potent than infection with either species alone in inducing NF-κB activity and proinflammatory cytokine secretion in monocytic cells and primary murine macrophages. Moreover, in a murine model of periodontitis, mixed infection with the two species induces synergistic alveolar bone loss, characterized by bone loss which is greater than the additive alveolar bone losses induced by each species alone. Further, in comparison to the single-species infection, mixed infection caused significantly increased inflammatory cell infiltration in the gingivae and osteoclastic activity in the jaw bones. These data show that F. nucleatum subspecies and T. forsythia synergistically stimulate the host immune response and induce alveolar bone loss in a murine experimental periodontitis model.

  17. MicroRNAs: Potential Biomarkers and Therapeutic Targets for Alveolar Bone Loss in Periodontal Disease

    Directory of Open Access Journals (Sweden)

    Tadayoshi Kagiya

    2016-08-01

    Full Text Available Periodontal disease is an inflammatory disease caused by bacterial infection of tooth-supporting structures, which results in the destruction of alveolar bone. Osteoclasts play a central role in bone destruction. Osteoclasts are tartrate-resistant acid phosphatase (TRAP-positive multinucleated giant cells derived from hematopoietic stem cells. Recently, we and other researchers revealed that microRNAs are involved in osteoclast differentiation. MicroRNAs are novel, single-stranded, non-coding, small (20–22 nucleotides RNAs that act in a sequence-specific manner to regulate gene expression at the post-transcriptional level through cleavage or translational repression of their target mRNAs. They regulate various biological activities such as cellular differentiation, apoptosis, cancer development, and inflammatory responses. In this review, the roles of microRNAs in osteoclast differentiation and function during alveolar bone destruction in periodontal disease are described.

  18. Large-scale microstructural simulation of load-adaptive bone remodeling in whole human vertebrae

    NARCIS (Netherlands)

    Badilatti, Sandro D.; Christen, Patrik; Levchuk, Alina; Hazrati Marangalou, Javad; Rietbergen, van Bert; Parkinson, Ian; Müller, Ralph

    2016-01-01

    Identification of individuals at risk of bone fractures remains challenging despite recent advances in bone strength assessment. In particular, the future degradation of the microstructure and load adaptation has been disregarded. Bone remodeling simulations have so far been restricted to small-volu

  19. The Effect of Irradiation on Bone Remodelling and the Structural Integrity of the Vertebral Column

    Science.gov (United States)

    1990-01-01

    1965. Schantz, A, AL Schiller and SP Kadish. Localized aplasia in irradiated vertebral bone marrow: A frequently overlooked gross observation. Arch...undergo the bone remodelling sequence together bone marrow-the soft, fatty substance filling the medullary cavaties and spongy extremities of the long

  20. Cola beverage consumption delays alveolar bone healing: a histometric study in rats

    Directory of Open Access Journals (Sweden)

    Juliana Mazzonetto Teófilo

    2010-06-01

    Full Text Available Epidemiological studies have suggested that cola beverage consumption may affect bone metabolism and increase bone fracture risk. Experimental evidence linking cola beverage consumption to deleterious effects on bone is lacking. Herein, we investigated whether cola beverage consumption from weaning to early puberty delays the rate of reparative bone formation inside the socket of an extracted tooth in rats. Twenty male Wistar rats received cola beverage (cola group or tap water (control group ad libitum from the age of 23 days until tooth extraction at 42 days and euthanasia 2 and 3 weeks later. The neoformed bone volume inside the alveolar socket was estimated in semi-serial longitudinal sections using a quantitative differential point-counting method. Histological examination suggested a decrease in the osteogenic process within the tooth sockets of rats from both cola groups, which had thinner and sparser new bone trabeculae. Histometric data confirmed that alveolar bone healing was significantly delayed in cola-fed rats at three weeks after tooth extraction (ANOVA, p = 0.0006, followed by Tukey's test, p < 0.01. Although the results of studies in rats cannot be extrapolated directly to human clinical dentistry, the present study provides evidence that cola beverage consumption negatively affect maxillary bone formation.

  1. Particulate bioglass in the regeneration of alveolar bone in dogs: clinical, surgical and radiographic evaluations

    Directory of Open Access Journals (Sweden)

    Alexandre Couto Tsiomis

    2011-04-01

    Full Text Available Bone loss, either by trauma or other diseases, generates an increasing need for substitutes of this tissue. This study evaluated Bioglass as a bone substitute in the regeneration of the alveolar bone in mandibles of dogs by clinical, surgical and radiological analysis. Twenty-eight adult dogs were randomly separated into two equal groups. In each animal, a bone defect was created on the vestibular surface of the alveolar bone between the roots of the fourth right premolar tooth. In the treated group, the defect was immediately filled with bioglass, while in the control, it remained unfilled. Clinical evaluations were performed daily for a week, as well as x-rays immediately after surgery and at 8, 14, 21, 42, 60, 90 and 120 days post-operative. Most animals in both groups showed no signs of inflammation and wound healing was similar. Radiographic examination revealed a gradual increase of radiopacity in the region of the defect in the control group. In the treated group, initial radiopacity was higher than that of adjacent bone, decreasing until 21 days after surgery. Then it gradually increased until 120 days after surgery, when the defect became undetectable. The results showed that Bioglass integrates into bone tissue, is biocompatible and reduced the period for complete bone regeneration.

  2. Measurement of maxillary sinus volume and available alveolar bone height using computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Hak; Han, Won Jeong; Choi, Young Hi; Kim, Eun Kyung [Dankook University College of Medicine, Seoul (Korea, Republic of)

    2003-03-15

    To aid in determining the volume of graft bone required before a maxillary sinus lift procedure and compare the alveolar bone height measurements taken by panoramic radiographs to those by CT images. Data obtained by both panoramic radiographs and CT examination of 25 patients were used in this study. Maxillary sinus volumes from the antral floor to heights of 5 mm, 10 mm, 15 mm, and 20 mm , were calculated. Alveolar bone height was measured on the panoramic images at each maxillary tooth site and corrected by magnification rate (PBH). Available bone height (ABH) and full bone height (FBH) was measured on reconstructed CT images. PBH was compared with ABH and FBH at the maxillary incisors, canines, premolars, and molars. Volumes of the inferior portion of the sinuses were 0.55 {+-} 0.41 cm{sup 3} for 5 mm lifts, 2.11 {+-} 0.68 cm{sup 3} for 10 mm, 4.26 {+-} 1.32 cm{sup 3} for 15 mm, 6.95 {+-} 2.01 cm{sup 3} for 20 mm. For the alveolar bone measurement, measurements by panoramic images were longer than available bone heights determined by CT images at the incisor and canine areas, and shorter than full bone heights on CT images at incisor, premolar, and molar areas (p<0.001). In bone grafting of the maxillary sinus floor, 0,96 cm{sup 3} or more is required for a 5 mm - lift, 2.79 cm{sup 3} or more for a 10 mm - lift, 5.58 cm{sup 3} or more for a 15 mm - lift, and 8.96 cm{sup 3} or more for a 20 mm - lift. Maxillary implant length determined using panoramic radiograph alone could result in underestimation or overestimation, according to the site involved.

  3. Histological Features and Biocompatibility of Bone and Soft Tissue Substitutes in the Atrophic Alveolar Ridge Reconstruction

    Directory of Open Access Journals (Sweden)

    Carlo Maiorana

    2016-01-01

    Full Text Available The reconstruction of the atrophic alveolar ridges for implant placement is today a common procedure in dentistry daily practice. The surgical reconstruction provides for the optimization of the supporting bone for the implants and a restoration of the amount of keratinized gingiva for esthetic and functional reasons. In the past, tissue regeneration has been performed with autogenous bone and free gingival or connective tissue grafts. Nowadays, bone substitutes and specific collagen matrix allow for a complete restoration of the atrophic ridge without invasive harvesting procedures. A maxillary reconstruction of an atrophic ridge by means of tissue substitutes and its histological features are then presented.

  4. The zebrafish as a model for tissue regeneration and bone remodelling

    NARCIS (Netherlands)

    Sharif, Faiza

    2011-01-01

    The aim of this thesis was to investigate the expression, and function of genes associated with remodelling and regeneration in the zebrafish model species. Here, we studied the role of cell populations, defined by their expression of markers, in bone regeneration and remodelling in zebrafish embryo

  5. Alveolar bone grafting in association with polyostotic fibrous dysplasia and bisphosphonate-induced abnormal bone turnover in a bilateral cleft lip and palate patient: a case report.

    Science.gov (United States)

    Kodama, Yasumitsu; Ogose, Akira; Oguri, Yoshimitsu; Ubaidus, Sobhan; Iizuka, Tateyuki; Takagi, Ritsuo

    2012-09-01

    A case is presented of extensive alveolar bone grafting in a patient with bilateral cleft lip and palate and polyostotic fibrous dysplasia. The patient previously underwent bisphosphonate therapy. Because of an abnormal and often decreased bone turnover caused by the fibrous dysplasia and the bisphosphonate therapy, bone grafting in such a patient poses several potential difficulties. In addition, the histomorphometric analysis of the bone grafts showed markedly decreased bone turnover. However, alveolar bone grafting using the iliac crest was performed successfully. Sufficient occlusion was achieved by postoperative low-loading orthodontic treatment.

  6. Effect of the interaction between periodontitis and type 1 diabetes mellitus on alveolar bone, mandibular condyle and tibia.

    Science.gov (United States)

    Kim, Ji-Hye; Lee, Dong-Eun; Gunawardhana, K S Niluka Darshani; Choi, Seong-Ho; Woo, Gye-Hyeong; Cha, Jeong-Heon; Bak, Eun-Jung; Yoo, Yun-Jung

    2014-05-01

    This study examined the effect of the interaction between periodontitis and type 1 diabetes mellitus on alveolar bone, mandibular condyle and tibia in animal models. Rats were divided into normal, periodontitis, diabetic and diabetic with periodontitis groups. After injection of streptozotocin to induce diabetes, periodontitis was induced by ligation of both lower-side first molars for 30 days. Alveolar bone loss and trabecular bone volume fraction (BVF) of the mandibular condyle and tibia were estimated via hematoxylin and eosin staining and micro-computed tomography, respectively. Osteoclastogenesis of bone marrow cells isolated from tibia and femur was assayed using tartrate-resistant acid phosphatase staining. The cemento-enamel junction to the alveolar bone crest distance and ratio of periodontal ligament area in the diabetic with periodontitis group were significantly increased compared to those of the periodontitis group. Mandibular condyle BVF did not differ among groups. The BVF of tibia in the diabetic and diabetic with periodontitis groups was lower than that of the normal and periodontitis groups. Osteoclastogenesis of bone marrow cells in the diabetic groups was higher than that in the non-diabetic groups. However, the BVF of tibia and osteoclastogenesis in the diabetic with periodontitis group were not significantly different than those in the diabetic group. Type 1 diabetes mellitus aggravates alveolar bone loss induced by periodontitis, but periodontitis does not alter the mandibular condyle and tibia bone loss induced by diabetes. Alveolar bone, mandibular condyle and tibia may have different responses to bone loss stimuli in the diabetic environment.

  7. An integrative approach for comparing microcirculation between normal and alveolar cleft gingiva in children scheduled for secondary bone grafting procedures

    NARCIS (Netherlands)

    D.M.J. Milstein; Y.W. Cheung; L. Ziukaite; C. Ince; H.P. van den Akker; J.A.H. Lindeboom

    2013-01-01

    Objective The aim of this study was to compare microcirculatory parameters in normal versus alveolar cleft gingiva in children selected for secondary bone grafting procedures. Study Design This study included 11 consecutive patients with complete unilateral alveolar clefts who required secondary bon

  8. 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.

  9. Rac-null leukocytes are associated with increased inflammation-mediated alveolar bone loss.

    Science.gov (United States)

    Sima, Corneliu; Gastfreund, Shoshi; Sun, Chunxiang; Glogauer, Michael

    2014-02-01

    Periodontitis is characterized by altered host-biofilm interactions that result in irreversible inflammation-mediated alveolar bone loss. Genetic and epigenetic factors that predispose to ineffective control of biofilm composition and maintenance of tissue homeostasis are not fully understood. We elucidated how leukocytes affect the course of periodontitis in Rac-null mice. Mouse models of acute gingivitis and periodontitis were used to assess the early inflammatory response and patterns of chronicity leading to loss of alveolar bone due to inflammation in Rac-null mice. Leukocyte margination was differentially impaired in these mice during attachment in conditional Rac1-null (granulocyte/monocyte lineage) mice and during rolling and attachment in Rac2-null (all blood cells) mice. Inflammatory responses to subgingival ligatures, assessed by changes in peripheral blood differential leukocyte numbers, were altered in Rac-null compared with wild-type mice. In response to persistent subgingival ligature-mediated challenge, Rac-null mice had increased loss of alveolar bone with patterns of resorption characteristic of aggressive forms of periodontitis. These findings were partially explained by higher osteoclastic coverage of the bone-periodontal ligament interface in Rac-null compared with wild-type mice. In conclusion, this study demonstrates that leukocyte defects, such as decreased endothelial margination and tissue recruitment, are rate-limiting steps in the periodontal inflammatory process that lead to more aggressive forms of periodontitis.

  10. Melanocortin agonism as a viable strategy to control alveolar bone loss induced by oral infection.

    Science.gov (United States)

    Madeira, Mila F M; Queiroz-Junior, Celso M; Montero-Melendez, Trinidad; Werneck, Silvia M C; Corrêa, Jôice D; Soriani, Frederico M; Garlet, Gustavo P; Souza, Daniele G; Teixeira, Mauro M; Silva, Tarcilia A; Perretti, Mauro

    2016-12-01

    Alveolar bone loss is a result of an aggressive form of periodontal disease (PD) associated with Aggregatibacter actinomycetemcomitans (Aa) infection. PD is often observed with other systemic inflammatory conditions, including arthritis. Melanocortin peptides activate specific receptors to exert antiarthritic properties, avoiding excessing inflammation and modulating macrophage function. Recent work has indicated that melanocortin can control osteoclast development and function, but whether such protection takes place in infection-induced alveolar bone loss has not been investigated. The purpose of this study was to evaluate the role of melanocortin in Aa-induced PD. Mice were orally infected with Aa and treated with the melanocortin analog DTrp(8)-γMSH or vehicle daily for 30 d. Then, periodontal tissue was collected and analyzed. Aa-infected mice treated with DTrp(8)-γMSH presented decreased alveolar bone loss and a lower degree of neutrophil infiltration in the periodontium than vehicle-treated animals; these actions were associated with reduced periodontal levels of TNF-α, IFN-γ, and IL-17A. In vitro experiments with cells differentiated into osteoclasts showed that osteoclast formation and resorptive activity were attenuated after treatment with DTrp(8)-γMSH. Thus, melanocortin agonism could represent an innovative way to tame overexuberant inflammation and, at the same time, preserve bone physiology, as seen after Aa infection.-Madeira, M. F. M., Queiroz-Junior, C. M., Montero-Melendez, T., Werneck, S. M. C., Corrêa, J. D., Soriani, F. M., Garlet, G. P., Souza, D. G., Teixeira, M. M., Silva, T. A., Perretti, M. Melanocortin agonism as a viable strategy to control alveolar bone loss induced by oral infection. © FASEB.

  11. Modalities for Visualization of Cortical Bone Remodeling: The Past, Present, and Future.

    Science.gov (United States)

    Harrison, Kimberly D; Cooper, David M L

    2015-01-01

    Bone's ability to respond to load-related phenomena and repair microdamage is achieved through the remodeling process, which renews bone by activating groups of cells known as basic multicellular units (BMUs). The products of BMUs, secondary osteons, have been extensively studied via classic two-dimensional techniques, which have provided a wealth of information on how histomorphology relates to skeletal structure and function. Remodeling is critical in maintaining healthy bone tissue; however, in osteoporotic bone, imbalanced resorption results in increased bone fragility and fracture. With increasing life expectancy, such degenerative bone diseases are a growing concern. The three-dimensional (3D) morphology of BMUs and their correlation to function, however, are not well-characterized and little is known about the specific mechanisms that initiate and regulate their activity within cortical bone. We believe a key limitation has been the lack of 3D information about BMU morphology and activity. Thus, this paper reviews methodologies for 3D investigation of cortical bone remodeling and, specifically, structures associated with BMU activity (resorption spaces) and the structures they create (secondary osteons), spanning from histology to modern ex vivo imaging modalities, culminating with the growing potential of in vivo imaging. This collection of papers focuses on the theme of "putting the 'why' back into bone architecture." Remodeling is one of two mechanisms "how" bone structure is dynamically modified and thus an improved 3D understanding of this fundamental process is crucial to ultimately understanding the "why."

  12. 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...

  13. Osteocytic Sclerostin Expression in Alveolar Bone in Rats With Diabetes Mellitus and Ligature-Induced Periodontitis.

    Science.gov (United States)

    Kim, Ji-Hye; Lee, Dong-Eun; Woo, Gye-Hyeong; Cha, Jeong-Heon; Bak, Eun-Jung; Yoo, Yun-Jung

    2015-08-01

    Osteocytic sclerostin inhibits bone formation, and its expression is stimulated by tumor necrosis factor (TNF)-α. This study investigates sclerostin and TNF-α expression in rats with diabetes mellitus (DM) and periodontitis. Rats were divided into control (C), periodontitis (P), and DM + periodontitis (DP) groups. After induction of DM by streptozotocin, periodontitis was induced by ligature. At day 0 (control) and at days 3 and 20 after induction of periodontitis, alveolar bone, osteoclasts, osteoid area, and TNF-α and sclerostin expression were evaluated. The distance between the cemento-enamel junction and the alveolar bone crest of the DP group was longer than that of the P group at day 20 after induction of periodontitis, but the number of osteoclasts was not different. Osteoid area decreased in both the P and DP groups by day 3, but whereas sustained osteoid suppression was observed in the DP group at day 20, osteoid formation was increased in the P group. The number of sclerostin-positive osteocytes increased in both groups at day 3, but the increased number of sclerostin-positive osteocytes was maintained only in the DP group through day 20. The number of TNF-α-positive cells increased more in the DP group than in the P group. Enhanced alveolar bone loss, suppressed bone formation, and prevalent TNF-α expression were characteristic of the DP group compared with the P group. Suppressed bone formation in the DP group was observed simultaneously with increased sclerostin and TNF-α expression. These results suggest that upregulated osteocytic sclerostin expression in periodontitis accompanied by DM may play a role in suppressed bone formation.

  14. Radiographic evaluation of the effect of obesity on alveolar bone in rats with ligature-induced periodontal disease.

    Science.gov (United States)

    do Nascimento, Cassiane Merigo; Cassol, Tiago; da Silva, Fernanda Soares; Bonfleur, Maria Lucia; Nassar, Carlos Augusto; Nassar, Patricia Oehlmeyer

    2013-01-01

    There is evidence that the lack of metabolic control of obese patients may accelerate periodontitis. The aim of this study was to evaluate radiographically the effect of cafeteria-diet-induced obesity on alveolar bone loss in rats subjected to periodontal disease. Twenty male Wistar rats were randomly divided into four groups: 1) control group, 2) control and ligature group; 3) cafeteria group; and 4) cafeteria and ligature group. The animals were evaluated for obesity and euthanized, and the mandible of each rat was removed to perform a radiographic evaluation of alveolar bone loss and its effect on diet-induced obesity. The results showed greater alveolar bone loss in the mice in Group 4 (P<0.01). Thus, we concluded that obese mice, on average, showed greater radiographic evidence of alveolar bone loss than mice undergoing induction of obesity.

  15. 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.

  16. Effects of boric acid on experimental periodontitis and alveolar bone loss in rats.

    Science.gov (United States)

    Demirer, Serhat; Kara, M Isa; Erciyas, Kamile; Ozdemir, Hakan; Ozer, Hatice; Ay, Sinan

    2012-01-01

    The goal of the present study was to evaluate the histopathologic and morphometric effects of systemic boric acid in a rat periodontitis model. Twenty-four Wistar rats were divided into three groups of eight animals each: non-ligated (NL), ligature only (LO), and ligature and treated with boric acid (BA) (3mg/kg per day for 11 days). A 4/0 silk suture was placed in a subgingival position around the mandibular first molars; after 11 days the rats were sacrificed, and changes in alveolar bone levels were measured clinically and tissues were histopathologically examined to assess the differences amongst the study groups. The ratio of presence of inflammatory cell infiltration (ICI) and osteoclast number in the LO group was significantly higher than that of the NL and BA groups (pboric acid reduced periodontal inflammation and alveolar bone loss in periodontal disease in rats. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Alveolar bone loss associated to periodontal disease in lead intoxicated rats under environmental hypoxia.

    Science.gov (United States)

    Terrizzi, Antonela R; Fernandez-Solari, Javier; Lee, Ching M; Bozzini, Clarisa; Mandalunis, Patricia M; Elverdin, Juan C; Conti, María Ines; Martínez, María Pilar

    2013-10-01

    Previously reported studies from this laboratory revealed that rats chronically intoxicated with lead (Pb) under hypoxic conditions (HX) impaired growth parameters and induced damages on femoral and mandibular bones predisposing to fractures. We also described periodontal inflammatory processes under such experimental conditions. Periodontitis is characterised by inflammation of supporting tissues of the teeth that result in alveolar bone loss. The existence of populations living at high altitudes and exposed to lead contamination aimed us to establish the macroscopic, biochemical and histological parameters consistent with a periodontal disease in the same rat model with or without experimental periodontitis (EP). Sixty female rats were divided into: Control; Pb (1000ppm of lead acetate in drinking water); HX (506mbar) and PbHX (both treatments simultaneously). EP was induced by placing ligatures around the molars of half of the rats during the 14 days previous to the autopsy. Hemi-mandibles were extracted to evaluate bone loss by histomorphometrical techniques. TNFα plasmatic concentration was greater (palveolar bone loss, while Pb showed spontaneous bone loss also. In conclusion, these results show that lead intoxication under hypoxic environment enhanced not only alveolar bone loss but also systemic and oral tissues inflammatory parameters, which could aggravate the physiopathological alterations produced by periodontal disease.

  18. Sclerostin antibody treatment causes greater alveolar crest height and bone mass in an ovariectomized rat model of localized periodontitis.

    Science.gov (United States)

    Chen, Hui; Xu, Xinchen; Liu, Min; Zhang, Wen; Ke, Hua-zhu; Qin, An; Tang, Tingting; Lu, Eryi

    2015-07-01

    Periodontitis and osteoporosis are bone destructive diseases with a high prevalence in the adult population. The concomitant presence of osteoporosis may be a risk factor of progression of periodontal destruction. We studied the effect of sclerostin-neutralizing monoclonal antibody (Scl-Ab) on alveolar bone endpoints in an ovariectomized (OVX) rat model of induced experimental periodontitis. Sixty female, 4-month-old Sprague-Dawley rats underwent sham operation or bilateral OVX and were left untreated for 2 months. Experimental periodontitis (ligature) was established by placing silk sutures subgingival to the right maxillary first and second molar teeth for 4 weeks, and feeding the rats food and high-sugar drinking water during this period. Thereafter, ligatures were removed and 25mg/kg vehicle or Scl-Ab was administered subcutaneously twice weekly for 6 weeks. Rats were randomized into four groups: (1) Control (Sham+Vehicle), (2) Sham+Ligature+Vehicle, (3) OVX+Ligature+Vehicle, and (4) OVX + Ligature + Scl-Ab. Terminal blood and right maxilla specimens were collected for analyses. Group 3 rats showed lower bone volume fraction (BVF) of alveolar bone with higher bone resorption and lower bone formation than Group 2 rats. Group 4 rats had higher alveolar crest height, as assessed by linear distance of cementoenamel junction to the alveolar bone crest and greater alveolar bone mass using Micro CT, than Group 3 rats. Significantly higher values of mineral apposition rate (MAR) and mineralizing surface/bone surface (MS/BS) were also observed in Group 4 rats by analyzing polychrome sequential labeling data. Increased serum osteocalcin and osteoprotegerin, and deceased serum tartrate-resistant acid phosphatase and CTx-1 illustrate the ability of Scl-Ab to increase alveolar bone mass by enhancing bone formation and decreasing bone resorption in an animal model of estrogen deficiency osteopenia plus periodontitis. Scl-Ab could be a potential bone anabolic agent for

  19. Resolving of deficit alveolar ridges by induced bone regeneration- case report

    OpenAIRE

    2012-01-01

    The aim was to show illustrative, indication of alveolar augmentation before insertion of endoosseous dental implants. In our case report we have shown the indication for ridge augmentation prior to the placement of endoosseous dental implant. The local process of bone regeneration was thus stimulated and the chances of a good clinical output were increased. Case report: Female patient (27 years old) visited our clinic. Diagnosis was periodontitis of 46 and indication to remove the tooth, ...

  20. Modalities for visualization of cortical bone remodeling: the past, present and near future

    Directory of Open Access Journals (Sweden)

    Kimberly Dawn Harrison

    2015-08-01

    Full Text Available Bone’s ability to respond to load-related phenomena and repair microdamage is achieved through the remodeling process which renews bone by activating groups of cells known as Basic Multicellular Units (BMUs. The products of BMUs, secondary osteons, have been extensively studied via classic two-dimensional (2D techniques which have provided a wealth of information on how histomorphology relates to skeletal structure and function. Remodeling is critical in maintaining healthy bone tissue; however, in osteoporotic bone imbalanced resorption results in increased bone fragility and fracture. With increasing life expectancy, such degenerative bone diseases are a growing concern. The three-dimensional (3D morphology of BMUs and their correlation to function, however, are not well characterized and little is known about the specific mechanisms that initiate and regulate their activity within cortical bone. We believe a key limitation has been the lack 3D information about BMU morphology and activity. Thus, this paper reviews methodologies for 3D investigation of cortical bone remodeling and, specifically, structures associated with BMU activity (resorption spaces and the structures they create (secondary osteons, spanning from histology to modern ex vivo imaging modalities, culminating with the growing potential of in vivo imaging. This collection of papers focuses on the theme of putting the why back into bone archytecture. Remodeling is one of two mechanisms how bone structure is dynamically modified and thus an improved 3D understanding of this fundamental process is crucial to ultimately understanding the why.

  1. Instrumental and laboratory assessment of stressful remodelling processes in bone tissue at total hip replacement

    Directory of Open Access Journals (Sweden)

    E.V. Karjakina

    2010-06-01

    Full Text Available Research objective is to estimate stressful remodelling features of bone tissue according to the densitometry data and to the level of biochemical markers of bone resorption and formation in total hip replacement (THR. Bone tissue mineral density (BTMD, condition of calcium-phosphoric metabolism and biochemical markers of bone formation (osteocalcin and bone isoenzyme of alkaline phosphatase and resorption (С-terminal bodypeptide of the I type collagen have been determined in 52 patients with coxarthrosis of ll-lll stages with marked joint dysfunction before and after THR. The control group included 24 donors. The data were considered to be reliable when the probability index was р<0,05. The reliable (р<0,05 change of BTMD was determined only in 3-6 months after the operation, whereas the change of biochemical markers of remodeling had already been done after 1,5-3 months, allowing to define the group of patients with obvious negative bone balance: strong predominance of resorption processes without compensation of the subsequent adequate osteogenesis, that subsequently could lead to significant bone tissue deficiency in the area adjacent to the endoprosthesis. Changes of indices of calcium-phosphoric metabolism were not certain during the investigation term. ln conclusion it is to state that biochemical markers of remodeling in comparison with BTMD allow to estimate objectively features of adaptive bone tissue remodeling after THR in earlier periods and to define group of patients with sharp intensification of metabolism and obvious negative bone balance

  2. Boric acid inhibits alveolar bone loss in rats by affecting RANKL and osteoprotegerin expression.

    Science.gov (United States)

    Sağlam, M; Hatipoğlu, M; Köseoğlu, S; Esen, H H; Kelebek, S

    2014-08-01

    The goal of the present study was to evaluate the effects of systemic boric acid on the levels of expression of RANKL and osteoprotegerin (OPG) and on histopathologic and histometric changes in a rat periodontitis model. Twenty-four Wistar rats were divided into three groups of eight animals each: nonligated (NL); ligature only (LO); and ligature plus treatment with boric acid (BA) (3 mg/kg per day for 11 d). A 4/0 silk suture was placed in a subgingival position around the mandibular right first molars; after 11 d the rats were killed, and alveolar bone loss in the first molars was histometrically determined. Periodontal tissues were examined histopathologically to assess the differences among the study groups. RANKL and OPG were detected immunohistochemically. Alveolar bone loss was significantly higher in the LO group than in the BA and NL groups (p boric acid may reduce alveolar bone loss by affecting the RANKL/OPG balance in periodontal disease in rats. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. The influence of root surface distance to alveolar bone and periodontal ligament on periodontal wound healing

    Science.gov (United States)

    2016-01-01

    Purpose The purpose of this animal study was to perform a 3-dimensional micro-computed tomography (micro-CT) analysis in order to investigate the influence of root surface distance to the alveolar bone and the periodontal ligament on periodontal wound healing after a guided tissue regeneration (GTR) procedure. Methods Three adult Sus scrofa domesticus specimens were used. The study sample included 6 teeth, corresponding to 2 third mandibular incisors from each animal. After coronectomy, a circumferential bone defect was created in each tooth by means of calibrated piezoelectric inserts. The experimental defects had depths of 3 mm, 5 mm, 7 mm, 9 mm, and 11 mm, with a constant width of 2 mm. One tooth with no defect was used as a control. The defects were covered with a bioresorbable membrane and protected with a flap. After 6 months, the animals were euthanised and tissue blocks were harvested and preserved for micro-CT analysis. Results New alveolar bone was consistently present in all experimental defects. Signs of root resorption were observed in all samples, with the extent of resorption directly correlated to the vertical extent of the defect; the medial third of the root was the most commonly affected area. Signs of ankylosis were recorded in the defects that were 3 mm and 7 mm in depth. Density and other indicators of bone quality decreased with increasing defect depth. Conclusions After a GTR procedure, the periodontal ligament and the alveolar bone appeared to compete in periodontal wound healing. Moreover, the observed decrease in bone quality indicators suggests that intrabony defects beyond a critical size cannot be regenerated. This finding may be relevant for the clinical application of periodontal regeneration, since it implies that GTR has a dimensional limit. PMID:27800213

  4. Deoxypyridinoline level in gingival crevicular fluid as alveolar bone loss biomarker in periodontal disease

    Directory of Open Access Journals (Sweden)

    Agustin Wulan Suci Dharmayanti

    2012-06-01

    Full Text Available Background: Periodontal diseases have high prevalence in Indonesia. They are caused by bacteria plaque that induced host response to release pro inflammatory mediator. Pro inflammatory mediators and bacteria product cause degradation of collagen fibers in periodontal tissue. Deoxypyridinoline is one of pyridinoline cross-link of collagen type I that can be used as biomarker in bone metabolic diseases, however, their contribution to detect alveolar bone loss in periodontal diseases remains unclear. Purpose: This study was to evaluate deoxypyridinoline level in gingival crevicular fluid as alveolar bone loss biomarker on periodontal disease. Methods: This study used 24 subjects with periodontal diseases and 6 healthy subjects. Dividing of periodontal disease was based on index periodontal. Gingival crevicular fluid was taken at mesial site of maxillary posterior tooth by paper point and deoxypyridinoline be measured by ELISA technique. Results: We found increasing of deoxypyridinoline level following of the severity of periodontal diseases. There was also significant difference between healthy subjects and periodontal diseases subjects (p<0.05. Conclusion: Deoxypyridinoline level in gingiva crevicular fluid can be used as alveolar bone loss biomarker in periodontal disease subjects.Latar belakang: Prevalensi penyakit periodontal di Indonesia cukup tinggi. Ini disebabkan oleh bakteri plak yang merangsang respon tubuh untuk mengeluarkan mediator keradangan. Mediator keradangan dan produk bakteri menyebabkan degradasi serat kolagen jaringan periodontal. Deoksipiridinolin merupakan salah satu ikatan piridinium dari kolagen tipe I yang dapat digunakan sebagai biomarker penyakit metabolisme tubuh. Akan tetapi, penggunaan deoksipiridinolin untuk mendeteksi kehilangan tulang alveolar pada penyakit periodontal masih belum jelas. Tujuan: Tujuan penelitian ini untuk mengetahui bahwa kadar deoksipiridinolin pada cairan krevikular gingival dapat digunakan

  5. On a new law of bone remodeling based on damage elasticity: a thermodynamic approach

    Directory of Open Access Journals (Sweden)

    Idhammad Ahmed

    2012-11-01

    Full Text Available Abstract Background Bone tissue is the main element of the human skeleton and is a dynamic tissue that is continuously renewed by bone-resorbing osteoclasts and bone-forming osteoblasts. The bone is also capable of repairing itself and adapting its structure to changes in its load environment through the process of bone remodeling. Therefore, this phenomenon has been gaining increasing interest in the last years and many laws have been developed in order to simulate this process. Results In this paper, we develop a new law of bone remodeling in the context of damaged elastic by applying the thermodynamic approach in the case of small perturbations. The model is solved numerically by a finite difference method in the one-dimensional bone structure of a n-unit elements model. Conclusion In addition, several numerical simulations are presented that confirm the accuracy and effectiveness of the model.

  6. A multiscale analytical approach for bone remodeling simulations: linking scales from collagen to trabeculae.

    Science.gov (United States)

    Colloca, Michele; Blanchard, Romane; Hellmich, Christian; Ito, Keita; van Rietbergen, Bert

    2014-07-01

    Bone is a dynamic and hierarchical porous material whose spatial and temporal mechanical properties can vary considerably due to differences in its microstructure and due to remodeling. Hence, a multiscale analytical approach, which combines bone structural information at multiple scales to the remodeling cellular activities, could form an efficient, accurate and beneficial framework for the prognosis of changes in bone properties due to, e.g., bone diseases. In this study, an analytical formulation of bone remodeling integrated with multiscale micromechanical models is proposed to investigate the effects of structural changes at the nanometer level (collagen scale) on those at higher levels (tissue scale). Specific goals of this study are to derive a mechanical stimulus sensed by the osteocytes using a multiscale framework, to test the accuracy of the multiscale model for the prediction of bone density, and to demonstrate its multiscale capabilities by predicting changes in bone density due to changes occurring at the molecular level. At each different level, the bone composition was modeled as a two-phase material which made it possible to: (1) find a closed-form solution for the energy-based mechanical stimulus sensed by the osteocytes and (2) describe the anisotropic elastic properties at higher levels as a function of the stiffness of the elementary components (collagen, hydroxyapatite and water) at lower levels. The accuracy of the proposed multiscale model of bone remodeling was tested first by comparing the analytical bone volume fraction predictions to those obtained from the corresponding μFE-based computational model. Differences between analytical and numerical predictions were less than 1% while the computational time was drastically reduced, namely by a factor of 1 million. In a further analysis, the effects of changes in collagen and hydroxyapatite volume fractions on the bone remodeling process were simulated, and it was found that such changes

  7. Computation of bone remodelling after Duracon knee arthroplasty using a thermodynamic-based model.

    Science.gov (United States)

    Bougherara, H; Nazgooei, S; Sayyidmousavi, A; Marsik, F; Marík, I A

    2011-07-01

    The present study utilizes a recently developed literature model for the bone remodelling process to predict the evolution of bone density following Duracon total knee arthroplasty (TKA). In this model, which is based on chemical kinetics and irreversible thermodynamics, bone is treated as a self-organizing system capable of exchanging matter, energy, and entropy with its surroundings. Unlike previous models in which mechanical loading is regarded as the only stimulus for bone remodelling, the present model establishes a unique coupling between mechanical loading and the chemical reactions involved in the process of bone remodelling. This model was incorporated into the finite element software ANSYS by means of a macro to compute density distribution in distal femoral bone both before and after TKA. Consistent with dual-energy X-ray absorptiometry (DEXA) scans reported in the literature, the results showed that the most severe bone loss occurs in the anterior region of the distal femur and that there is more bone resorption in the lateral than the medial condyle following TKA. Furthermore, the bone density distribution predicted using the present model showed a gradual and uniform pattern and thus a more realistic bone evolution contrary to the strain energy density model, where there is no gradual bone density evolution.

  8. A randomized controlled evaluation of alveolar ridge preservation following tooth extraction using deproteinized bovine bone mineral and demineralized freeze-dried bone allograft

    Directory of Open Access Journals (Sweden)

    Rokhsareh Sadeghi

    2016-01-01

    Conclusion: Based on the findings of this study, both materials have positive effect on alveolar ridge preservation after tooth extraction, but there was more new bone formation and less residual graft particles in DFDBA group than in DBBM group.

  9. The potentiation of Mangifera casturi bark extract on interleukin- 1β and bone morphogenic protein-2 expressions during bone remodeling after tooth extraction

    Directory of Open Access Journals (Sweden)

    Bayu Indra Sukmana

    2017-03-01

    Full Text Available Background: The main oral health problem in Indonesia is the high number of tooth decay. Tooth extraction is the treatment often received by patients who experience tooth decay and the wound caused by alveolar bone resorption. Bark of Mangifera casturi has been studied and proven to contain secondary metabolite which has the ability to increase osteoblast’s activity and suppress osteoclast’s activity. Purpose: The purpose of this study was to analyze interleukin-1 beta (IL-1β and bone morphogenic protein-2 (BMP-2 activities during bone remodeling after Mangifera casturi’s bark extract treatment. Method: This study was laboratory experimental research with randomized post-test only control group design. The Mangifera casturi bark was extracted using 96% ethanol maceration and n-hexane fractionation. This study used 40 male Wistar rats which are divided into 4 groups and the tooth extraction was performed on the rats’ right mandible incisive tooth. The four groups consisted of 6.35%, 12.7%, 25.4% extract treatment group, and a control group. Wistar’s mandibles were decapitated on the 7th and 14th day after extraction. Antibody staining on preparations for the examination of IL-1β and BMP-2 expressions was done using immunohistochemistry. Result: There was a significant difference of IL-1β and BMP-2 expressions in 6,35%, 12,7%, and 25,4% treatment groups compared to control group with p<0.05. Conclusion: Mangifera casturi’s bark extract was able to suppress the IL-1β expression and increase the BMP-2 expression during bone remodeling after tooth extraction.

  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. A periodontal attachment mechanism without alveolar bone. Case report.

    Science.gov (United States)

    Novak, M J; Polson, A M; Caton, J; Freeman, E; Meitner, S

    1983-02-01

    A 22-year-old black male was referred for periodontal therapy because of radiographic evidence of advanced bone loss associated with the posterior teeth. Clinical examination revealed gingivitis, normal sulcus depths, and minimal loss of clinical attachment. Complete blood counts, serum chemistry, and neutrophil function were within normal limits. Histological, histochemical and ultrastructural analysis of an extracted tooth revealed no loss of attachment; large areas of the cementum were collagen-poor and, ultrastructurally, resembled afibrillar cementum. It is proposed that the periodontal attachment mechanism present in this case was associated with a localized failure in normal periodontal development.

  12. Action of Calciotropic Hormones on Bone Metabolism-Role of Vitamin D3 in Bone Remodeling Events

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    Catharine Andresen

    2006-01-01

    Full Text Available Vitamin D3 is known to have immunosuppressive effects that can be beneficial for treatment of immune disorders and transplant rejection, however therapeutic application is limited due to hypercalcemia and hypercalcuria. The goal of our studies was to explore both the acute and steady state effects of vitamin D3 on bone remodeling as potential limiting factors to broader use of vitamin D3 in the clinic. Vitamin D3 was evaluated for its skeletal effects in both thyroparathyroidectomized (TPTx and intact rat models. In TPTx rats, deprivation of thyroid and parathyroid hormones and calcitonin creates a low state of bone modeling and remodeling ideal for evaluation of changes imposed by drug intervention. The use of both models allowed for discrimination of individual (TPTx versus combined (intact effects of calciotropic hormones on bone and calcium metabolism. Our studies have confirmed the limitations of using vitamin D3 for treatment/co- treatment of immune disease in humans due to the intrinsic hypercalcemic properties of the hormone, and also highlighted the potential of vitamin D3 to negatively impact skeletal integrity due to excessive bone remodeling driven by bone resorption. Taken together our data emphasize the importance of including biomarkers of bone remodeling as an integral part of clinical and preclinical studies using vitamin D3 to treat immune disorders and suggest the need for co-treatment with an antiresorptive agent to counteract hypercalcemia and deterioration of bone.

  13. LRP6 in mesenchymal stem cells is required for bone formation during bone growth and bone remodeling

    Institute of Scientific and Technical Information of China (English)

    Changjun Li; Bart O Williams; Xu Cao; Mei Wan

    2014-01-01

    Lipoprotein receptor-related protein 6 (LRP6) plays a critical role in skeletal development and homeostasis in adults. However, the role of LRP6 in mesenchymal stem cells (MSCs), skeletal stem cells that give rise to osteoblastic lineage, is unknown. In this study, we generated mice lacking LRP6 expression specifically in nestin1 MSCs by crossing nestin-Cre mice with LRP6flox mice and investigated the functional changes of bone marrow MSCs and skeletal alterations. Mice with LRP6 deletion in nestin1 cells demonstrated reductions in body weight and body length at 1 and 3 months of age. Bone architecture measured by microCT (mCT) showed a significant reduction in bone mass in both trabecular and cortical bone of homozygous and heterozygous LRP6 mutant mice. A dramatic reduction in the numbers of osteoblasts but much less significant reduction in the numbers of osteoclasts was observed in the mutant mice. Osterix1 osteoprogenitors and osteocalcin1 osteoblasts significantly reduced at the secondary spongiosa area, but only moderately decreased at the primary spongiosa area in mutant mice. Bone marrow MSCs from the mutant mice showed decreased colony forming, cell viability and cell proliferation. Thus, LRP6 in bone marrow MSCs is essential for their survival and proliferation, and therefore, is a key positive regulator for bone formation during skeletal growth and remodeling.

  14. Influence of Alveolar Bone Loss and Cement Layer Thickness on the Biomechanical Behavior of Endodontically Treated Maxillary Incisors: A 3-dimensional Finite Element Analysis.

    Science.gov (United States)

    Dal Piva, Amanda Maria de Oliveira; Tribst, João Paulo Mendes; Souza, Rodrigo Othávio de Assunção E; Borges, Alexandre Luiz Souto

    2017-05-01

    In order to understand the mechanical behavior of a weakened incisor, this study aimed to evaluate the stress distribution caused by different alveolar bone heights and cement layer thickness. A finite element analysis was conducted for this investigation. An intact maxillary central incisor was initially modeled, and the bone of the models was modified in order to simulate 4 levels of bone height: BL0 (no bone loss), BL1 (1/3 bone loss), BL2 (1/2 bone loss), and BL3 (2/3 bone loss). These teeth models were remodeled with a fiber post at 2 different cement thicknesses and restored with a ceramic crown; "A" refers to the well-adapted fiber post (0.3 mm) and "B" to the nonadapted fiber post (1 mm), resulting in 12 models. RelyX ARC (3M ESPE, St Paul, MN) cement was simulated for the cementation of the crowns and fiber posts for all groups. Numeric models received a load of 100 N on the lingual surface. All materials and structures were considered linear elastic, homogeneous, and isotropic. Numeric models were plotted and meshed with isoparametric elements, and results were expressed in maximum principal stress. For fiberglass posts, cement, and dentin, the highest stress concentration occurred in the groups with increased bone loss. For cortical bone, the highest values were for the groups with 1/3 bone loss. A greater thickness of cement layer concentrates more stress. More bone loss and greater CLT were the influential factors in concentrating the stress. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  15. 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.

  16. Long-term effect of thin interdental alveolar bone on periodontal health after orthodontic treatment.

    Science.gov (United States)

    Artun, J; Osterberg, S K; Kokich, V G

    1986-06-01

    The present experiment was undertaken to determine if an interproximal area with a thin interdental bone septum following orthodontic treatment provides less resistance against marginal periodontal breakdown than an interproximal area with a normal width of bone between the roots. Only adult patients, at least 16 years after active orthodontic treatment, were studied. The distance between the roots was measured directly on periapical radiographs. Gingival health, level of attachment and bone level in sites with thin interdental bone were compared with neighboring or contralateral sites with a normal width of bone between the roots. No statistically significant differences in inflammation, level of attachment and clinical scores for bone level were observed. When measured radiographically the distance from the cementoenamel junction to the alveolar bone was significantly shorter in neighboring control sites (P less than 0.05). This discrepancy was most likely due to radiographic distortion. The results of this investigation suggest that in anterior areas marginal periodontal breakdown is unrelated to the thickness of bone between the roots. Too few molar sites were included to draw conclusions regarding such areas.

  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. CELLULAR MECHANISMS OF BONE REMODELING DUE TO EXTERNAL OVERLOAD AND UNDER CONDITIONS OF TITAN IMPLANT OSSEOINTEGRATION

    Directory of Open Access Journals (Sweden)

    Gaifullin N.M.

    2016-04-01

    Full Text Available The goal of article concludes to describe the remodeling of the femur, caused by two processes: the increased strain on supporting tissue as a result of anterior cruciate ligament transection and stimulation by installation of endosseous titanium implants with a porous bioactive coating. The process is traced through 4, 8 and 12 weeks in 28 adult Wistar rats. To characterize the bone remodeling the classical methods of histology and morphometry as well as immune histochemistry to reveal osteonectin, tartrate-resistant acid phosphatase, endothelial marker СD31, matrix metalloproteinases MMP-2, MMP-9, and its tissue inhibitor TIMP-1, were used with necessary morphometrics. The study showed for bone remodelling caused by implants with a porous bioactive coating, to be superior to a similar process under conditions of overload on the bone after transection of the anterior cruciate ligament by its intensity and dynamics. This indicates a high osteoinductive effect of bioactive coating that allows not only to achieve full osseointegration, but also to stimulate a process of intensive remodeling of adjacent cancellous bone. The cooperative participation of cell populations as osteoblasts/osteocytes, osteoclasts, and endothelial cells with characteristic parallel intensive expression of matrix metalloproteinases MMP-2, MMP-9 and their tissue inhibitor TIMP-1, used to be main characteristics of bone remodeling in these conditions.

  19. [Morphometric evaluation of changes in the alveolar bone of adolescents with bimaxillary protrusion via cone beam computed tomography].

    Science.gov (United States)

    Yinghong, Liu; Zeyuan, Zhou; Kui, Zhao; Caomin, Tang; Jun, Wang

    2016-02-01

    This study aimed to evaluate the morphometric changes in the alveolar bone of the maxillary and mandibular anterior regions after retraction in adolescents. The sample size comprised 30 adolescent patients with class 1 bimaxillary protrusion (12 males and 18 females, age: 12-18 years old) and were treated by extracting four first pre-molars. Cone beam computed tomography (CBCT) was performed 1 month before and 1 month after the retraction. For each maxillary and mandibular anterior tooth, the labial and palatal alveolar plates at cervical 1/3, middle 1/3, and apical 1/3 levels for bone thickness changes during the retraction of the maxillary and mandibular anterior regions were checked. The movements of cervical 1/3, middle 1/3, and apical 1/3 levels of the maxillary central incisor were measured. Statistical analyses were performed with SPSS 16.0. For the adolescents, alveolar bone thickness increased on the labial side and decreased on the palatal side. The alveolar bone thicknesses of cervical 1/3 and middle 1/3 of maxillary central incisor, cervical 1/3 and apical 1/3 of maxillary lateral incisor, middle 1/3 of mandibular central incisor, apical 1/3 of mandibular lateral incisor, and middle 1/3 and apical 1/3 of mandibular canine all increased after retraction. By contrast, the alveolar bone thickness of the apical 1/3 of maxillary canine and the cervical 1/3 of mandibular canine decreased after retraction. No statistically significant difference was observed in other region. During retraction, a controlled tipping movement occur in adolescents. After retraction, the alveolar bone thickness of the labial side increase, whereas that of the palatal side decrease. Moreover, the thicknesses of major areas in the alveolar bone significantly increase.

  20. Correlations between initial cleft size and dental anomalies in unilateral cleft lip and palate patients after alveolar bone grafting.

    Science.gov (United States)

    Jabbari, Fatima; Reiser, Erika; Thor, Andreas; Hakelius, Malin; Nowinski, Daniel

    2016-01-01

    Objective To determine in individuals with unilateral cleft lip and palate the correlation between initial cleft size and dental anomalies, and the outcome of alveolar bone grafting. Methods A total of 67 consecutive patients with non-syndromic unilateral complete cleft lip and palate (UCLP) were included from the cleft lip and palate-craniofacial center, Uppsala University Hospital, Sweden. All patients were operated by the same surgeon and treated according to the Uppsala protocol entailing: lip plasty at 3 months, soft palate closure at 6 months, closure of the residual cleft in the hard palate at 2 years of age, and secondary alveolar bone grafting (SABG) prior to the eruption of the permanent canine. Cleft size was measured on dental casts obtained at the time of primary lip plasty. Dental anomalies were registered on radiographs and dental casts obtained before bone grafting. Alveolar bone height was evaluated with the Modified Bergland Index (mBI) at 1 and 10-year follow-up. Results Anterior cleft width correlated positively with enamel hypoplasia and rotation of the central incisor adjacent to the cleft. There was, however, no correlation between initial cleft width and alveolar bone height at either 1 or 10 years follow-up. Conclusions Wider clefts did not seem to have an impact on the success of secondary alveolar bone grafting but appeared to be associated with a higher degree of some dental anomalies. This finding may have implications for patient counseling and treatment planning.

  1. The roles of exercise in bone remodeling and in prevention and treatment of osteoporosis.

    Science.gov (United States)

    Yuan, Yu; Chen, Xi; Zhang, Lingli; Wu, Juanni; Guo, Jianming; Zou, Dongchen; Chen, Binglin; Sun, Zhongguang; Shen, Chao; Zou, Jun

    2016-11-01

    With a rapid increase in the aging population, osteoporosis has become a global health problem. Although anti-resorption and anabolic drugs are available, osteoporosis cannot be completely cured. Exercise is an economical, efficacious, and safe way to prevent the development of osteoporosis. Recent studies have investigated the mechanisms by which exercise affects bone remodeling. Here we update the progress made on the effects of exercise on bone cells, including bone marrow mesenchymal stem cells, osteoblasts, osteocytes, and osteoclasts, as well as on bone mass, bone strength, and geometry, hoping to provide a theoretical basis to improve osteoporosis prevention and treatment with exercise.

  2. [Evaluation of alveolar bone defects on anterior region in patients with bimaxillary protrusion by using cone-beam CT].

    Science.gov (United States)

    Zhou, Lin; Li, Wei-ran

    2015-06-18

    To investigate the alveolar bone defects of anterior alveolar bone in patients with bimaxillary protrusion by using cone-beam computed tomography (CBCT). The samples consisted of 50 patients with bimaxillary protrusion, who were assigned to the teenage group[20 cases, (13.1±1.0) years] and adult group[30 cases, (22.9±4.2) years]. The adult group included 9 hypo-divergent, 11 normo-divergent and 10 hyper-divergent patients. The images were obtained by using NewTom VG CBCT and the alveolar defects were evaluated. The ratio of the patients had alveolar bone defects was 94.00%. Meanwhile, the defects were associated with 38.60% of all the teeth. Most defects occurred on labial alveolar bone (98.66%); fenestration was found more in the maxillary alveolar region and dehiscence occurred more in the mandible. The dehiscences (3.06%) and defects prevalence (30.13%) of the teenage group were significant lower than those of the adult group (11.73% vs. 42.46%), P0.05). The hypo-divergent group had lower fenestrations prevalence (22.22%) than the normo-divergent (33.84%) and hyper-divergent groups (37.50%), Pbimaxillary protrusion before orthodontic treatment. The prevalence of defects is affected by age and vertical-growth type.

  3. CELLULAR MECHANISMS OF BONE REMODELING DUE TO EXTERNAL OVERLOAD AND UNDER CONDITIONS OF TITAN IMPLANT OSSEOINTEGRATION

    OpenAIRE

    Gaifullin N.M.

    2016-01-01

    The goal of article concludes to describe the remodeling of the femur, caused by two processes: the increased strain on supporting tissue as a result of anterior cruciate ligament transection and stimulation by installation of endosseous titanium implants with a porous bioactive coating. The process is traced through 4, 8 and 12 weeks in 28 adult Wistar rats. To characterize the bone remodeling the classical methods of histology and morphometry as well as immune histochemistry to reveal osteo...

  4. 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.

  5. 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

  6. Using smooth particle hydrodynamics to investigate femoral cortical bone remodelling at the Haversian level.

    Science.gov (United States)

    Fernandez, J W; Das, R; Cleary, P W; Hunter, P J; Thomas, C D L; Clement, J G

    2013-01-01

    In the neck of the femur, about 70% of the strength is contributed by the cortical bone, which is the most highly stressed part of the structure and is the site where failure is almost certainly initiated. A better understanding of cortical bone remodelling mechanisms can help discern changes at this anatomical site, which are essential if an understanding of the mechanisms by which hips weaken and become vulnerable to fracture is to be gained. The aims of this study were to (i) examine a hypothesis that low strain fields arise because of subject-specific Haversian canal distributions causing bone resorption and reduced bone integrity and (ii) introduce the use of a meshless particle-based computational modelling approach SPH to capture bone remodelling features at the level of the Haversian canals. We show that bone remodelling initiated by strain at the Haversian level is highly influenced by the subject-specific pore distribution, bone density, loading and osteocyte density. SPH is shown to be effective at capturing the intricate bone pore shapes that evolved over time.

  7. A Femur-Implant Model for the Prediction of Bone Remodeling Behavior Induced by Cementless Stem

    Institute of Scientific and Technical Information of China (English)

    He Gong; Lingyan Kong; Rui Zhang; Juan Fang; Meisheng Zhao

    2013-01-01

    Bone remodeling simulation is an effective tool for the prediction of long-term effect of implant on the bone tissue,as well as the selection of an appropriate implant in terms of architecture and material.In this paper,a finite element model of proximal femur was develop.ed to simulate the structures of internal trabecular and cortical bones by incorporating quantitative bone functional adaptation theory with finite element analysis.Cementless stems made of titanium,two types of Functionally Graded Material (FGM) and flexible 'iso-elastic' material as comparison were implanted in the structure of proximal femur respectively to simulate the bone remodeling behaviors of host bone.The distributions of bone density,von Mises stress,and interface shear stress were obtained.All the prosthetic stems had effects on the bone remodeling behaviors of proximal femur,but the degrees of stress shielding were different.The amount of bone loss caused by titanium implant was in agreement with the clinical observation.The FGM stems caused less bone loss than that of the titanium stem,in which FGM I stem (titanium richer at the top to more HAP/Col towards the bottom) could relieve stress shielding effectively,and the interface shear stresses were more evenly distributed in the model with FGM I stem in comparison with those in the models with FGM II (titanium and bioglass) and titanium stems.The numerical simulations in the present study provided theoretical basis for FGM as an appropriate material of femoral implant from a biomechanical point of view.The next steps are to fabricate FGM stem and to conduct animal experiments to investigate the effects of FGM stem on the remodeling behaviors using animal model.

  8. Alveolar bone dynamics in osteoporotic rats treated with raloxifene or alendronate: confocal microscopy analysis

    Science.gov (United States)

    Ramalho-Ferreira, Gabriel; Faverani, Leonardo Perez; Grossi-Oliveira, Gustavo Augusto; Okamoto, Tetuo; Okamoto, Roberta

    2015-03-01

    In this study, the characteristics of the alveolar bone of rats with induced osteoporosis were examined. Thirty-two rats were divided into four groups according to the induction of osteoporosis and drugs administered: OG, osteoporotic rats without treatment (negative control); SG, rats which underwent sham surgery ovariectomy (SHAM); alendronate (AG), osteoporotic rats treated with alendronate; and RG, osteoporotic rats treated with raloxifene (RG). On the 8th day after ovariectomy and SHAM surgeries, drug therapy was started with AG or RG. On the 52nd day, 20 mg/kg calcein was administered to all of the rats, and on the 80th day, 20 mg/kg alizarin red was administered. Euthanasia was performed on the 98th day. The bone area marked by fluorochromes was calculated and data were subjected to two-way ANOVA test and Tukey's post-hoc test (pbone turnover only between RG and SG (p=0.074) and AG and OG (p=0.138). All other comparisons showed significant differences (pbone turnover was observed in RG and SG groups. RG was the medication that improved the dynamics of the alveolar bone of rats with induced osteoporosis, resembling that of healthy rats.

  9. Relationship between the morphologic features of alveolar trabecular bone and systemic osteoporosis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Jin; Chang, Hoon Sang; Lee, Byung Do [Wonkwang University College of Medicine, Iksan (Korea, Republic of)

    2005-09-15

    The purpose of this study was to investigate the preliminary use of morphologic operation (MO) in analyzing trabecular pattern of alveolar bone for the predicting systemic osteoporosis. Study subjects consisted of 35 females (average age 48.5 years) and 25 males (average age 25.8 years). Bone mineral density BMD (grams/cm) of lumbar spine and proximal femur of these subjects were measured by a dual energy X-ray absorptiometry (DEXA). Regions of interest (ROIs) were selected from the digitized peri apical radiographs of subjects' posterior jaw. A custom computer program processed morphology operations of ROIs. We compared mean values of 11 MO variables according to the osteoporotic group divided by the T-scores of DEXA. We also studied correlation between radiographic density and these MO variables. The mean radiographic densities insignificantly correlated with MO variables. There were statistically significant differences among the values of 9 MO variables according to the osteoporotic group. Morphologic operation can be effective in analyzing trabecular pattern of alveolar bone for the predicting osteoporosis.

  10. 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.)

  11. Regional variability in secondary remodeling within long bone cortices of catarrhine primates: the influence of bone growth history.

    Science.gov (United States)

    McFarlin, Shannon C; Terranova, Carl J; Zihlman, Adrienne L; Enlow, Donald H; Bromage, Timothy G

    2008-09-01

    Secondary intracortical remodeling of bone varies considerably among and within vertebrate skeletons. Although prior research has shed important light on its biomechanical significance, factors accounting for this variability remain poorly understood. We examined regional patterning of secondary osteonal bone in an ontogenetic series of wild-collected primates, at the midshaft femur and humerus of Chlorocebus (Cercopithecus) aethiops (n = 32) and Hylobates lar (n = 28), and the midshaft femur of Pan troglodytes (n = 12). Our major objectives were: 1) to determine whether secondary osteonal bone exhibits significant regional patterning across inner, mid-cortical and outer circumferential cortical rings within cross-sections; and if so, 2) to consider the manner in which this regional patterning may reflect the influence of relative tissue age and other circumstances of bone growth. Using same field-of-view images of 100-microm-thick cross-sections acquired in brightfield and circularly polarized light microscopy, we quantified the percent area of secondary osteonal bone (%HAV) for whole cross-sections and across the three circumferential rings within cross-sections. We expected bone areas with inner and middle rings to exhibit higher %HAV than the outer cortical ring within cross-sections, the latter comprising tissues of more recent depositional history. Observations of primary bone microstructural development provided an additional context in which to evaluate regional patterning of intracortical remodeling. Results demonstrated significant regional variability in %HAV within all skeletal sites. As predicted,%HAV was usually lowest in the outer cortical ring within cross-sections. However, regional patterning across inner vs. mid-cortical rings showed a more variable pattern across taxa, age classes, and skeletal sites examined. Observations of primary bone microstructure revealed that the distribution of endosteally deposited bone had an important influence on

  12. 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...

  13. Root abnormalities, talon cusps, dentes invaginati with reduced alveolar bone levels: case report.

    LENUS (Irish Health Repository)

    McNamara, C M

    1998-03-01

    This is a case report of a Caucasian female who presented with an unusual combination of dental anomalies: short roots on the maxillary central incisors and premolars, talon cusps, dentes invaginati, low alveolar bone heights, tubercles of Carabelli on the maxillary first and second permanent molars, with pyramidal root morphology in three of the second permanent molars. None of the anomalies alone are particularly uncommon but they have not previously been reported together. The occurrence of the anomalies is probably incidental as the conditions are aetiologically unrelated.

  14. IFITM1 increases osteogenesis through Runx2 in human alveolar-derived bone marrow stromal cells.

    Science.gov (United States)

    Kim, Beom-Su; Kim, Hyung-Jin; Kim, Jin Seong; You, Yong-Ouk; Zadeh, Homa; Shin, Hong-In; Lee, Seung-Jin; Park, Yoon-Jeong; Takata, Takashi; Pi, Sung-Hee; Lee, Jun; You, Hyung-Keun

    2012-09-01

    The exact molecular mechanisms governing the differentiation of bone marrow stromal stem/progenitor cells (BMSCs) into osteoblasts remain largely unknown. In this study, a highly expressed protein that had a high degree of homology with interferon-induced transmembrane protein 1 (IFITM1) was identified using differentially expressed gene (DEG) screening. We sought to determine whether IFITM1 influenced osteoblast differentiation. During differentiation, IFITM1 expression gradually increased from 5 to 10days and subsequently decreased at 15 days in culture. Analysis of IFITM1 protein expression in several cell lines as well as in situ studies on human tissues revealed its selective expression in bone cells and human bone. Proliferation of human alveolar-derived bone marrow stromal cells (hAD-BMSCs) was significantly inhibited by IFITM1 knockdown by using short hairpin RNA, as were bone specific markers such as alkaline phosphatase, collagen type I α 1, bone sialoprotein, osteocalcin, and osterix were decreased. Calcium accumulation also decreased following IFITM1 knockdown. Moreover, IFITM1 knockdown in hAD-BMSCs was associated with inhibition of Runx2 mRNA and protein expression. Collectively, the present data provide evidence for the role of IFITM1 in osteoblast differentiation. The exact mechanisms of IFITM1's involvement in osteoblast differentiation are still under investigation.

  15. Periodontal ligament, cementum, and alveolar bone in the oldest herbivorous tetrapods, and their evolutionary significance.

    Science.gov (United States)

    LeBlanc, Aaron R H; Reisz, Robert R

    2013-01-01

    Tooth implantation provides important phylogenetic and functional information about the dentitions of amniotes. Traditionally, only mammals and crocodilians have been considered truly thecodont, because their tooth roots are coated in layers of cementum for anchorage of the periodontal ligament, which is in turn attached to the bone lining the alveolus, the alveolar bone. The histological properties and developmental origins of these three periodontal tissues have been studied extensively in mammals and crocodilians, but the identities of the periodontal tissues in other amniotes remain poorly studied. Early work on dental histology of basal amniotes concluded that most possess a simplified tooth attachment in which the tooth root is ankylosed to a pedestal composed of "bone of attachment", which is in turn fused to the jaw. More recent studies have concluded that stereotypically thecodont tissues are also present in non-mammalian, non-crocodilian amniotes, but these studies were limited to crown groups or secondarily aquatic reptiles. As the sister group to Amniota, and the first tetrapods to exhibit dental occlusion, diadectids are the ideal candidates for studies of dental evolution among terrestrial vertebrates because they can be used to test hypotheses of development and homology in deep time. Our study of Permo-Carboniferous diadectid tetrapod teeth and dental tissues reveal the presence of two types of cementum, periodontal ligament, and alveolar bone, and therefore the earliest record of true thecodonty in a tetrapod. These discoveries in a stem amniote allow us to hypothesize that the ability to produce the tissues that characterize thecodonty in mammals and crocodilians is very ancient and plesiomorphic for Amniota. Consequently, all other forms of tooth implantation in crown amniotes are derived arrangements of one or more of these periodontal tissues and not simply ankylosis of teeth to the jaw by plesiomorphically retaining "bone of attachment", as

  16. Integration of a Finite Element Model with the DAP Bone Remodeling Model to Characterize Bone Response to Skeletal Loading

    Science.gov (United States)

    Werner, Christopher R.; Mulugeta, Lealem; Myers, J. G.; Pennline, J. A.

    2015-01-01

    NASA's Digital Astronaut Project (DAP) has developed a bone remodeling model that has been validated for predicting volumetric bone mineral density (vBMD) changes of trabecular and cortical bone in the absence of mechanical loading. The model was recently updated to include skeletal loading from exercise and free living activities to maintain healthy bone using a new daily load stimulus (DLS). This new formula was developed based on an extensive review of existing DLS formulas, as discussed in the abstract by Pennline et al. The DLS formula incorporated into the bone remodeling model utilizes strains and stress calculated from finite element model (FEM) of the bone region of interest. The proximal femur was selected for the initial application of the DLS formula, with a specific focus on the femoral neck. METHODS: The FEM was generated from CAD geometry of a femur using de-identified CT data. The femur was meshed using linear tetrahedral elements Figure (1) with higher mesh densities in the femoral neck region, which is the primary region of interest for the initial application of the DLS formula in concert with the DAP bone remodeling model. Nodal loads were applied to the femoral head and the greater trochanter and the base of the femur was held fixed. An L2 norm study was conducted to reduce the length of the femoral shaft without significantly impacting the stresses in the femoral neck. The material properties of the FEM of the proximal femur were separated between cortical and trabecular regions to work with the bone remodeling model. Determining the elements with cortical material properties in the FEM was based off of publicly available CT hip scans [4] that were segmented, cleaned, and overlaid onto the FEM.

  17. Graft Remodeling following Transcrestal Sinus Floor Elevation via the Gel-Pressure Technique (GPT and Pasteous Nano-Crystalline Hydroxyapatite Bone Substitute

    Directory of Open Access Journals (Sweden)

    Bernhard Pommer

    2015-06-01

    Full Text Available Bone grafting of the maxillary sinus is attempted to compensate for sinus pneumatization and permit reliable insertion of endosseous dental implants for prosthetic rehabilitation. The aim of the present clinical investigation was to study bone regeneration four months after transcrestal sinus floor elevation via the Gel-Pressure Technique (GPT and application of pasteous nano-crystalline hydroxyapatite bone substitute. A total of 25 patients with deficient alveolar ridges in the posterior maxilla (mean residual bone height: 4.7 ± 1.8 mm were subjected to 32 flapless transcrestal sinus floor augmentations and simultaneous insertion of 40 implants. Sinus membrane elevation height averaged 11.2 ± 2.7 mm and minimal vertical graft resorption of 0.1 mm was observed after four months. Radiographic bone density averaged 460 Hounsfield units in regions adjacent to the native jawbone (1 to 7 mm distance, while reduction of bone density by −7.2%, −11.3%, −14.8%, −19.6% and −22.7% was recorded in more apical regions of 8, 9, 10, 11, and ≥12 mm distance to the original sinus floor, respectively. The results suggest that graft remodeling is completed up to a distance of 7 mm within a healing period of four months after sinus augmentation using nano-crystalline hydroxyapatite bone substitute material.

  18. Bone remodeling in the context of cellular and systemic regulation: the role of osteocytes and the nervous system.

    Science.gov (United States)

    Niedźwiedzki, Tadeusz; Filipowska, Joanna

    2015-10-01

    Bone is a dynamic tissue that undergoes constant remodeling. The appropriate course of this process determines development and regeneration of the skeleton. Tight molecular control of bone remodeling is vital for the maintenance of appropriate physiology and microarchitecture of the bone, providing homeostasis, also at the systemic level. The process of remodeling is regulated by a rich innervation of the skeleton, being the source of various growth factors, neurotransmitters, and hormones regulating function of the bone. Although the course of bone remodeling at the cellular level is mainly associated with the activity of osteoclasts and osteoblasts, recently also osteocytes have gained a growing interest as the principal regulators of bone turnover. Osteocytes play a significant role in the regulation of osteogenesis, releasing sclerostin (SOST), an inhibitor of bone formation. The process of bone turnover, especially osteogenesis, is also modulated by extra-skeletal molecules. Proliferation and differentiation of osteoblasts are promoted by the brain-derived serotonin and hypothetically inhibited by its intestinal equivalent. The activity of SOST and serotonin is either directly or indirectly associated with the canonical Wnt/β-catenin signaling pathway, the main regulatory pathway of osteoblasts function. The impairment of bone remodeling may lead to many skeletal diseases, such as high bone mass syndrome or osteoporosis. In this paper, we review the most recent data on the cellular and molecular mechanisms of bone remodeling control, with particular emphasis on the role of osteocytes and the nervous system in this process.

  19. Management of maxillary alveolar bone fracture and severely intruded maxillary central incisor: report of a case.

    Science.gov (United States)

    Yonezawa, Hisanobu; Yanamoto, Souichi; Hoshino, Tomonori; Yamada, Shin-Ichi; Fujiwara, Taku; Umeda, Masahiro

    2013-10-01

    An 11-year-old male who injured his maxilla and right maxillary central incisor and lip during a fall was presented to our hospital. His lower lip and upper gingiva were lacerated with swelling and epistaxis, and he had a maxillary alveolar bone fracture and severe intrusion of the right maxillary central incisor, which had penetrated the floor of the nasal cavity with avulsion. Under local anesthesia, we repositioned the incisor and bone segment and fixed them with a titanium micromesh plate and self-tapping screws and splints. The incisor was also treated by root canal 3 days after the operation and was restored with a crown. We performed root canal filling 1 month later. Five months later, the plate and screws were removed. In prognosis of our case, no symptoms of inflammatory root resorption or ankylosis have observed for more than 1 year and 6 months of follow up based on both clinical and radiographic findings.

  20. The ARF Tumor Suppressor Regulates Bone Remodeling and Osteosarcoma Development in Mice

    Science.gov (United States)

    Harding, John C.; Deng, Hongju; Shea, Lauren K.; Eagleton, Mark C.; Niewiesk, Stefan; Lairmore, Michael D.; Piwnica-Worms, David; Rosol, Thomas J.; Weber, Jason D.; Ratner, Lee; Weilbaecher, Katherine N.

    2010-01-01

    The ARF tumor suppressor regulates p53 as well as basic developmental processes independent of p53, including osteoclast activation, by controlling ribosomal biogenesis. Here we provide evidence that ARF is a master regulator of bone remodeling and osteosarcoma (OS) development in mice. Arf-/- mice displayed increased osteoblast (OB) and osteoclast (OC) activity with a significant net increase in trabecular bone volume. The long bones of Arf-/- mice had increased expression of OB genes while Arf-/- OB showed enhanced differentiation in vitro. Mice transgenic for the Tax oncogene develop lymphocytic tumors with associated osteolytic lesions, while Tax+Arf-/- mice uniformly developed spontaneous OS by 7 months of age. Tax+Arf-/- tumors were well differentiated OS characterized by an abundance of new bone with OC recruitment, expressed OB markers and displayed intact levels of p53 mRNA and reduced Rb transcript levels. Cell lines established from OS recapitulated characteristics of the primary tumor, including the expression of mature OB markers and ability to form mineralized tumors when transplanted. Loss of heterozygosity in OS tumors arising in Tax+Arf+/- mice emphasized the necessity of ARF-loss in OS development. Hypothesizing that inhibition of ARF-regulated bone remodeling would repress development of OS, we demonstrated that treatment of Tax+Arf-/- mice with zoledronic acid, a bisphosphonate inhibitor of OC activity and repressor of bone turnover, prevented or delayed the onset of OS. These data describe a novel role for ARF as a regulator of bone remodeling through effects on both OB and OC. Finally, these data underscore the potential of targeting bone remodeling as adjuvant therapy or in patients with genetic predispositions to prevent the development of OS. PMID:21209895

  1. Assessment of the changes in alveolar bone quality after fixed orthodontic therapy: A trabecular structure analysis

    Science.gov (United States)

    Haghnegahdar, Abdolaziz; Zarif Najafi, Hooman; Sabet, Maryam; Saki, Maryam

    2016-01-01

    Background. Tooth displacement changes the periodontium. The aim of orthodontic treatment is desired tooth movement with minimum side effects on the alveolar bone quality. The aim of the present study was to assess changes of alveolar trabeculation in children, young adults and adults and the two genders. Methods. In this cross-sectional study, 63 patients who had been treated in Department of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran, were chosen with convenient sampling method. They were divided into three groups based on their age. Their digitized panoramic radiographs (PRs) were evaluated at six interdental sites from the mesial aspect of the mandibular second molars to the distal aspect of the mandibular first premolars using a visual index. The trabeculation pattern was assigned as either dense (score 3), dense-sparse (score 2) or sparse (score 1). Data were imported to SPSS. Mean of the scores before treatment (score B) and mean of them after treatment (score A) were compared for each group with paired t-test. Changes between score B and sore A of the groups were compared using one-way ANOVA and post hoc tests. Results. Mean score A was significantly higher than mean score B in children (P = 0.001). In contrast, mean score A was significantly lower than mean score B in young adults (P = 0.003). Conclusion. Orthodontists should be cautious when treating young adults and adults regarding the probable, yet possibly temporary, negative effects of orthodontic therapy on the alveolar bone quality. PMID:28096944

  2. Impact of cannabis sativa (marijuana) smoke on alveolar bone loss: a histometric study in rats.

    Science.gov (United States)

    Nogueira-Filho, Getulio R; Todescan, Sylvia; Shah, Adnan; Rosa, Bruno T; Tunes, Urbino da R; Cesar Neto, Joao B

    2011-11-01

    Cannabis sativa (marijuana) can interfere with bone physiopathology because of its effect on osteoblast and osteoclast activity. However, its impact on periodontal tissues is still controversial. The present study evaluates whether marijuana smoke affects bone loss (BL) on ligature-induced periodontitis in rats. Thirty male Wistar rats were used in the study. A ligature was placed around one of the mandible first molars (ligated teeth) of each animal, and they were then randomly assigned to one of two groups: control (n = 15) or marijuana smoke inhalation ([MSI] for 8 minutes per day; n = 15). Urine samples were obtained to detect the presence of tetrahydrocannabinol. After 30 days, the animals were sacrificed and decalcified sections of the furcation area were obtained and evaluated according to the following histometric parameters: bone area (BA), bone density (BD), and BL. Tetrahydrocannabinol was positive in urine samples only for the rats of the MSI group. Non-significant differences were observed for unligated teeth from both groups regarding BL, BA, and BD (P >0.05). However, intragroup analysis showed that all ligated teeth presented BL and a lower BA and BD compared to unligated teeth (P <0.05). The intergroup evaluation of the ligated teeth showed that the MSI group presented higher BL and lower BD (P <0.05) compared to ligated teeth from the control group. Considering the limitations of this animal study, cannabis smoke may impact alveolar bone by increasing BL resulting from ligature-induced periodontitis.

  3. Transforming growth factor-beta1 adsorbed to tricalciumphosphate coated implants increases peri-implant bone remodeling

    DEFF Research Database (Denmark)

    Lin, M.; Overgaard, S; Glerup, H

    2001-01-01

    )-coated implants can improve mechanical fixation and bone ongrowth. The present study evaluated bone remodeling in newly formed bone and adjacent trabecular bone around TCP-coated implants with and without rhTGF-beta1 adsorption. Unloaded cylindrical grit-blasted titanium alloy implants coated with TCP were...

  4. Evaluation of unilateral cleft lip and palate using anthropometry measurements post-alveolar bone grafting

    Science.gov (United States)

    Simorangkir, H. J.; Hak, M. S.; Tofani, I.

    2017-08-01

    Rehabilitation of patients with unilateral cleft lip and palate (UCLP) requires multiple steps and coordination of multidisciplinary sciences to produce optimal results. Alveolar bone-grafting (ABG) is an important procedure in the treatment of such patients because it influences the eruption of teeth and stabilizes the maxilla. To evaluate the effect and suitability of alveolar bone grafting procedure at Cleft Center Harapan Kita Maternal and Child Hospital on nasal deformity from anthropometry with photogrammetry and aesthetic proportional in patients with unilateral cleft lip and palate with UCLP. Patients with UCLP were evaluated post-ABG using anthropometry and photogrammetry to investigate the results anteriorly, laterally, and basally. Anthropometric measurements taken photogrammetrically used 14 points and 11 distance items. Evaluations were made of upper lip length, upper lip projection, and nostril sill elevation for both the cleft and non-cleft sides of patients’ faces. A t-test showed that the values for upper lip length and projection were significantly increased, and a correction test using a Fisher exam gave a value of 1. The ABG treatment protocol for patients with UCLP at the Cleft Lip and Palate Unit at Harapan Kita Maternal and Child Hospital is suitable to be performed; it aesthetically satisfies patients and their families.

  5. The reversal phase of the bone-remodeling cycle

    DEFF Research Database (Denmark)

    Delaisse, Jean-Marie

    2014-01-01

    for the cells leading to osteogenesis during the reversal phase. This review aims at creating awareness of these cells and their activities in adult cancellous bone. It relates cell events (i) on the bone surface, (ii) in the mesenchymal envelope surrounding the bone marrow and appearing as a canopy above...... under the osteogenic influence of capillaries and osteoclasts, whereas bone surface cells become exposed to the eroded matrix and other osteoclast products. In several diverse pathophysiological situations, including osteoporosis, a decreased availability of osteoprogenitors from these local reservoirs...... coincides with decreased osteoblast recruitment and impaired initiation of bone formation, that is, uncoupling. Overall, this review stresses that coupling does not only depend on molecules able to activate osteogenesis, but that it also demands the presence of osteoprogenitors and ordered cell...

  6. Adaptive bone-remodeling theory applied to prosthetic-design analysis

    NARCIS (Netherlands)

    R. Huiskes (Rik); H.H. Weinans (Harrie); H.J. Grootenboer; M. Dalstra; B. Fudala; T.J. Slooff

    1987-01-01

    textabstractThe subject of this article is the development and application of computer-simulation methods to predict stress-related adaptive bone remodeling, in accordance with 'Wolff's Law'. These models are based on the Finite Element Method (FEM) in combination with numerical formulations of adap

  7. Chronic alcoholism and bone remodeling processes: Caveats and considerations for the forensic anthropologist.

    Science.gov (United States)

    Michael, Amy R; Bengtson, Jennifer D

    2016-02-01

    Clinical literature provides substantial information on the effects of chronic alcohol abuse on bone remodeling and related skeletal disease processes. This biomedical information is seldom considered in detail by forensic anthropologists, who often rely on normative macroscopic models of bone remodeling and traditional macroscopic age estimation methods in the creation of biological profiles. The case study presented here considers the ways that alcoholism disrupts normal bone remodeling processes, thus skewing estimations of age-at-death. Alcoholism affects bone macroscopically, resulting in a porous appearance and an older estimation of age, while simultaneously inhibiting osteoblastic activity and resulting in a younger microscopic appearance. Forensic anthropologists must also be cognizant of pathological remodeling stemming from alcoholism in cases where trauma analysis is critical to the reconstruction of events leading up to death, as fracture healing rates can be affected. Beyond the case study, we also consider how forensic anthropologists and practitioners can recognize and account for osteological signatures of alcoholism in medico-legal contexts. In order to best estimate age at death, a combined macroscopic and microscopic approach should be employed whenever possible alcohol and drug abuse is known or suspected.

  8. Pilot study: digital subtraction radiography as a tool to assess alveolar bone changes in periodontitis patients under treatment with subantimicrobial doses of doxycycline

    NARCIS (Netherlands)

    A.D. Goren; S.M. Dunn; M. Wolff; P.F. van der Stelt; D.C. Colosi; L.M. Golub

    2008-01-01

    Background Subtle changes in marginal alveolar bone level can be demonstrated using digital subtraction of sequential radiographs. Objective We aimed to evaluate the practical application of geometrically corrected digital subtraction in a clinical study of alveolar bone response to a drug previousl

  9. Effect of slow forced eruption on the vertical levels of the interproximal bone and papilla and the width of the alveolar ridge

    Science.gov (United States)

    Kwon, Eun-Young; Lee, Ju-Youn

    2016-01-01

    Objective Forced eruption has been proposed for the reconstruction of deficient bone and soft tissue. The aim of this study was to examine the changes in the alveolar ridge width and the vertical levels of the interproximal bone and papilla following forced eruption. Methods Patients whose hopeless maxillary anterior teeth were expected to undergo severe bone resorption and soft tissue recession upon extraction were recruited. In addition, patients whose maxillary anterior teeth required forced eruption for restoration due to tooth fracture or dental caries were included. Before and after forced eruption, the interproximal bone height was measured by radiographic analysis, and changes in the alveolar ridge width and the interproximal papilla height were measured with an acrylic stent. Results This prospective study demonstrated that the levels of the interproximal alveolar bone and papilla were significantly increased by 1.36 mm and 1.09 mm, respectively, in the vertical direction. However, the alveolar ridge width was significantly reduced by an average of 0.67 mm in the buccolingual direction. The changes in the level of the interproximal alveolar bone and papilla were positively correlated. Conclusions Although the levels of the interproximal bone and papilla were significantly increased, the alveolar ridge width was significantly decreased following forced eruption. There was a modest positive and significant correlation between the changes in the height of the interproximal alveolar bone and the papilla. Based on our findings, modification of vertical forced eruption should be considered when augmentation of the alveolar ridge width is required. PMID:27896212

  10. A mathematical model of cortical bone remodeling at cellular level under mechanical stimulus

    Institute of Scientific and Technical Information of China (English)

    Qing-Hua Qin; Ya-Nan Wang

    2012-01-01

    A bone cell population dynamics model for cortical bone remodeling under mechanical stimulus is developed in this paper.The external experiments extracted from the literature which have not been used in the creation of the model are used to test the validity of the model.Not only can the model compare reasonably well with these experimental results such as the increase percentage of final values of bone mineral content (BMC) and bone fracture energy (BFE) among different loading schemes (which proves the validity of the model),but also predict the realtime development pattern of BMC and BFE,as well as the dynamics of osteoblasts (OBA),osteoclasts (OCA),nitric oxide (NO) and prostaglandin E2 (PGE2) for each loading scheme,which can hardly be monitored through experiment.In conclusion,the model is the first of its kind that is able to provide an insight into the quantitative mechanism of bone remodeling at cellular level by which bone cells are activated by mechanical stimulus in order to start resorption/formation of bone mass.More importantly,this model has laid a solid foundation based on which future work such as systemic control theory analysis of bone remodeling under mechanical stimulus can be investigated.The to-be identified control mechanism will help to develop effective drugs and combined nonpharmacological therapies to combat bone loss pathologies.Also this deeper understanding of how mechanical forces quantitatively interact with skeletal tissue is essential for the generation of bone tissue for tissue replacement purposes in tissue engineering.

  11. Does Simulated Spaceflight Modify Epigenetic Status During Bone Remodeling?

    Science.gov (United States)

    Thomas, Nicholas J.; Stevick, Rebecca J.; Tran, Luan H.; Nalavadi, Mohit O.; Almeida, Eduardo A.C.; Globus, Ruth K.; Alwood, Joshua S.

    2015-01-01

    Little is known about the effects of spaceflight conditions on epigenetics. The term epigenetics describes changes to the genome that can affect expression of a gene without changes to the sequence of DNA. Epigenetic processes are thought to underlie cellular differentiation, where transcription of specific genes occurs in response to key stimuli, and may be heritable - passing from one cell to its daughter cell. We hypothesize that the mechanical environment during spaceflight, namely microgravity-induced weightlessness or exercise regulate gene expression in the osteoblast-lineage cells both to control bone formation by osteoblasts and bone resorption by osteoclasts, which continually shapes bone structure throughout life. Similarly we intend to evaluate how radiation regulates these same bone cell activity and differentiation related genes. We further hypothesize that the regulation in bone cell gene expression is at least partially controlled through epigenetic mechanisms of methylation or small non-coding RNA (microRNAs). We have acquired preliminary data suggesting that global genome methylation is modified in response to axial compression of the tibia - a model of exercise. We intend to pursue these hypotheses wherein we will evaluate changes in gene expression and, congruently, changes in epigenetic state in bones from mice subjected to the aforementioned conditions: hindlimb unloading to simulate weightlessness, axial compression of the tibia, or radiation exposure in order to gain insight into the role of epigenetics in spaceflight-induced bone loss.

  12. Assessment of Alveolar Bone Status in Middle Aged Chinese (40-59 Years with Chronic Periodontitis--Using CBCT.

    Directory of Open Access Journals (Sweden)

    Haijiao Zhao

    Full Text Available This study used con-beam computed tomography (CBCT to investigate the prevalence and severity of alveolar bone loss in middle-aged (40-59 years Chinese with chronic periodontitis.The study group comprised 145 dentate individuals aged 40 to 59 years residing in China who suffered from chronic periodontitis. CBCT and the application of NNT software were used to examine the level and location of alveolar bone loss.The study revealed that 40-59 year old patients with chronic periodontitis had severe bone loss. At 5,286 sites (34.7%, alveolar bone loss was mild; severe alveolar bone loss was found at 5,978 sites (39.2%. A comparison of bone loss in different jaws revealed that the area with the highest degree of bone loss was on the lingual side of the maxillary molar (56.3 ± 7.2%, and that the area with the lowest degree was primarily on the lingual side of the mandibular canine (27.5 ± 6.3%. There was a lower degree of alveolar bone loss in males than females. Differences were observed when comparing the incidence of bone loss between males and females (P < 0.05. Menopause in females and smoking in both genders may affect the level of bone loss. Male smokers experienced a greater degree of bone loss (41.67 ± 5.76% than male non-smokers (32.95 ± 4.31%. A 42.23 ± 6.34% bone loss was found in menopausal females versus 31.35 ± 3.62% in non-menopausal females.The study revealed that different sites and teeth exhibited a diverse degree of bone loss. In middle-aged patients with chronic periodontitis, the highest degrees of bone loss in the incisors, premolars, and molars were on the lingual side, mesial side and lingual side, respectively. Menopause in females and smoking may affect the level of bone loss.

  13. Comparison of two methods for alveolar bone loss measurement in an experimental periodontal disease model in rats

    Directory of Open Access Journals (Sweden)

    Diego Nique Liberman

    2011-02-01

    Full Text Available There are many studies that evaluate possible risk factors for periodontal diseases in animals. Most of them have focused only on the biological aspects of disease occurrence; therefore, it has been difficult to compare studies of the different methodological approaches. The aim of the present study was to compare different methods - linear and area - of the evaluation of morphometrical alveolar bone loss. Sixty hemimaxillae, defleshed and stained with 1% methylene blue to delineate the cementoenamel junction and alveolar bone crest, were obtained from a previous study that induced periodontal disease by means of ligatures in two groups of fifteen Wistar rats during 9 weeks. Ligatures were placed around the right upper second molars, and the contra-lateral teeth remained as intra-group controls. Digital photographs were taken from the specimens and submitted to a single, calibrated, blind examiner who performed the morphometrical evaluation of alveolar bone loss using both linear and area methods. Mean values of linear and area measurements were obtained from each side - buccal and palatal - of the specimens. The degree of association between the two methods was determined by Pearson's Correlation Coefficient. An almost perfect association (0.98 was determined between the linear and area evaluations. A mathematical formula was subsequently created to estimate the total area of alveolar bone loss, from linear mean measurements. Both methods were suitable for detecting bone level alterations. The results of the present study allow for the transformation of data and better compilation of results from different studies.

  14. Histological examination on osteoblastic activities in the alveolar bone of transgenic mice with induced ablation of osteocytes.

    Science.gov (United States)

    Li, Minqi; Hasegawa, Tomoka; Hogo, Hiromi; Tatsumi, Sawako; Liu, Zhusheng; Guo, Ying; Sasaki, Muneteru; Tabata, Chihiro; Yamamoto, Tsuneyuki; Ikeda, Kyoji; Amizuka, Norio

    2013-03-01

    The purpose of this study was to examine histological alterations on osteoblasts from the alveolar bone of transgenic mice with targeted ablation of osteoctyes. Eighteen weeks-old transgenic mice based on the diphtheria toxin (DT) receptor-mediated cell knockout (TRECK) system were used in these experiments. Mice were injected intraperitoneally with 50 µg/kg of DT in PBS, or only PBS as control. Two weeks after injections, mice were subjected to transcardiac perfusion with 4% paraformaldehyde in 0.1M phosphate buffer (pH 7.4), and the available alveolar bone was removed for histochemical analyses. Approximately 75% of osteocytes from alveolar bones became apoptotic after DT administration, and most osteocytic lacunae became empty. Osteoblastic numbers and alkaline phosphatase (ALP) activity were markedly reduced at the endosteum of alveolar bone after DT administration compared with the control. Osteoblastic ALP activity in the periodontal ligament region, on the other hand, hardly showed any differences between the two groups even though numbers were reduced in the experiment group. Silver impregnation showed a difference in the distribution of bone canaliculi between the portions near the endosteum and the periodontal ligament: the former appeared regularly arranged in contrast to the latter's irregular distribution. Under transmission electron microscopy (TEM), the osteoblasts in the periodontal ligament showed direct contact with the Sharpey's fibers. Thus, osteoblastic activity was affected by osteocyte ablation in general, but osteoblasts in contact with the periodontal ligament were less affected than endosteal osteoblasts.

  15. Root length and alveolar bone level of impacted canines and adjacent teeth after orthodontic traction: a long-term evaluation

    Science.gov (United States)

    da SILVA, Aldir Cordeiro; CAPISTRANO, Anderson; de ALMEIDA-PEDRIN, Renata Rodrigues; CARDOSO, Maurício de Almeida; CONTI, Ana Cláudia de Castro Ferreira; CAPELOZZA, Leopoldino

    2017-01-01

    Abstract Objective The aim of this retrospective study was to evaluate the long-term effects of orthodontic traction on root length and alveolar bone level in impacted canines and adjacent teeth. Material and Methods Sample consisted of 16 patients (nine males and seven females), mean initial age 11 years and 8 months presenting with unilaterally maxillary impacted canines, palatally displaced, treated with the same surgical and orthodontic approach. Teeth from the impacted-canine side were assigned as Group I (GI), and contralateral teeth as control, Group II (GII). The mean age of patients at the end of orthodontic treatment was 14 years and 2 months and the mean post-treatment time was 5 years and 11 months. Both contralateral erupted maxillary canines and adjacent teeth served as control. Root length and alveolar bone level (buccal and palatal) were evaluated on cone-beam computed tomography (CBCT) images. The comparison of root length and alveolar bone level changes between groups were assessed by applying paired t-test, at a significance level of 5% (p<0.05). Results There were no statistically significant differences in root length and buccal and palatal bone levels of canines and adjacent teeth among groups. Conclusions Impacted canine treatment by closed-eruption technique associated with canine crown perforation, has a minimal effect on root length and buccal and palatal alveolar bone level in both canine and adjacent teeth, demonstrating that this treatment protocol has a good long-term prognosis. PMID:28198979

  16. Comparison of Cone Beam Computed Tomography-Derived Alveolar Bone Density Between Subjects with and without Aggressive Periodontitis

    Science.gov (United States)

    Al-Zahrani, Mohammad S.; Elfirt, Eman Y.; Al-Ahmari, Manea M.; Yamany, Ibrahim A.; Alabdulkarim, Maher A.

    2017-01-01

    Introduction Understanding the changes in bone density of patients affected by aggressive periodontitis could be useful in early disease detection and proper treatment planning. Aim The aim of this study was to compare alveolar bone density in patients affected with aggressive periodontitis and periodontally healthy individuals using Cone Beam Computed Tomography (CBCT). Materials and Methods This cross-sectional study was conducted on 20 patients with a confirmed diagnosis of aggressive periodontitis. Twenty periodontally healthy patients attending the dental clinics for implant placement or extraction of impacted third molars served as controls. Alveolar bone density was measured using CBCT scanning. Comparisons between aggressive periodontitis group and controls for age and alveolar bone density of the anterior and posterior regions were performed using an independent sample t-test. Multivariable linear regression models were also performed. Results The differences between groups in regard to age, anterior and posterior alveolar bone density was not statistically significant (pperiodontitis patients was not different from periodontally healthy individuals. Further studies are needed to confirm these findings. PMID:28274060

  17. 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%.

  18. The efficacy of hydrothermally obtained carbonated hydroxyapatite in healing alveolar bone defects in rats with or without corticosteroid treatment

    Directory of Open Access Journals (Sweden)

    Marković Dejan

    2014-01-01

    Full Text Available Background/Aim. Autogenous bone grafting has been the gold standard in clinical cases when bone grafts are required for bone defects in dentistry. The study was undertaken to evaluate multilevel designed carbonated hydroxyapatite (CHA obtained by hydrothermal method, as a bone substitute in healing bone defects with or without corticosteroid treatment in rats as assessed by histopathologic methods. Methods. Bone defects were created in the alveolar bone by teeth extraction in 12 rats. The animals were initially divided into two groups. The experimental group was pretreated with corticosteroids: methylprednisolone and dexamethasone, intramuscularly, while the control group was without therapy. Posterior teeth extraction had been performed after the corticosteroid therapy. The extraction defects were fulfilled with hydroxyapatite with bimodal particle sizes in the range of 50-250 μm and the sample from postextocactional defect of the alveolar bone was analyzed pathohystologically. Results. The histopatological investigations confirmed the biologic properties of the applied material. The evident growth of new bone in the alveolar ridge was clearly noticed in both groups of rats. Carbonated HA obtained by hydrothermal method promoted bone formation in the preformed defects, confirming its efficacy for usage in bone defects. Complete resorption of the material’s particles took place after 25 weeks. Conclusion. Hydroxyapatite completely meets the clinical requirements for a bone substitute material. Due to its microstructure, complete resorption took place during the observation period of the study. Corticosteroid treatment did not significantly affect new bone formation in the region of postextractional defects. [Projekat Ministarstva nauke Republike Srbije, br. 172026

  19. Relationship between alveolar bone measured by /sup 125/I absorptiometry with analysis of standardized radiographs: 2. Bjorn technique

    Energy Technology Data Exchange (ETDEWEB)

    Ortman, L.F.; McHenry, K.; Hausmann, E.

    1982-05-01

    The Bjorn technique is widely used in periodontal studies as a standardized measure of alveolar bone. Recent studies have demonstrated the feasibility of using /sup 125/I absorptiometry to measure bone mass. The purpose of this study was to compare /sup 125/I absorptiometry with the Bjorn technique in detecting small sequential losses of alveolary bone. Four periodontal-like defects of incrementally increasing size were produced in alveolar bone in the posterior segment of the maxilla of a human skull. An attempt was made to sequentially reduce the amount of bone in 10% increments until no bone remained, a through and through defect. The bone remaining at each step was measured using /sup 125/I absorptiometry. At each site the /sup 125/I absorptiometry measurements were made at the same location by fixing the photon source to a prefabricated precision-made occlusal splint. This site was just beneath the crest and midway between the borders of two adjacent teeth. Bone loss was also determined by the Bjorn technique. Standardized intraoral films were taken using a custom-fitted acrylic clutch, and bone measurements were made from the root apex to coronal height of the lamina dura. A comparison of the data indicates that: (1) in early bone loss, less than 30%, the Bjorn technique underestimates the amount of loss, and (2) in advanced bone loss, more than 60% the Bjorn technique overestimates it.

  20. 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.

  1. Micromolar sodium fluoride mediates anti-osteoclastogenesis in Porphyromonas gingivalis-induced alveolar bone loss

    Institute of Scientific and Technical Information of China (English)

    Ujjal K Bhawal; Nobushiro Hamada; Ikuo Nasu; Hirohisa Arakawa; Koh Shibutani; Hye-Jin Lee; Kazumune Arikawa; Michiharu Shimosaka; Masatoshi Suzuki; Toshizo Toyama; Takenori Sato; Ryota Kawamata; Chieko Taguchi

    2015-01-01

    Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors. Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases. Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride (NaF) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. NaF strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin (IL)-1b, matrix metalloproteinase 9 (MMP9), and tartrate-resistant acid phosphatase, which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect, NaF inhibited osteoclast formation caused by the differentiation factor RANKL (receptor activator of nuclear factor kB ligand) and macrophage colony-stimulating factor (M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells (NFAT) c1 was also abrogated by NaF. Taken together, our data demonstrate that NaF inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9. The in vivo effect of NaF on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of NaF for treating periodontal diseases.

  2. 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

  3. Rapid maxillary expansion in alveolar cleft repaired with a tissue-engineered bone in a canine model.

    Science.gov (United States)

    Huang, Jialiang; Tian, Bo; Chu, Fengting; Yang, Chenjie; Zhao, Jun; Jiang, Xinquan; Qian, Yufen

    2015-08-01

    This study aims to investigate the effects of orthodontic expansion on graft area of a tissue-engineered bone (TEB) BMSCs/β-TCP, and to find an alternative strategy for the therapy of alveolar cleft. A unilateral alveolar cleft canine model was established and then treated with BMSCs/β-TCP under rapid maxillary expansion (RME). Sequential fluorescent labeling, radiography and helical computed tomography were used to evaluate new bone formation and mineralization in the graft area. Hematoxylin-eosin staining and Van Gieson׳s picro fuchsin staining were performed for histological and histomorphometric observation. ALP activity, mineralization and the expression of osteogenic differentiation related genes of BMSCs that grew on the β-TCP scaffold were promoted by their cultivation in osteogenic medium. Based on fact, TEB was constructed. After 8 weeks of treatment with BMSCs/β-TCP followed by RME, new bone formation and mineralization of the dogs were markedly accelerated, and bone resorption was significantly reduced, compared with the untreated dogs, or those only treated with autogenous iliac bone. The treatment with both TEB and RME evidently made the bone trabecula more abundant and the area of bone formation larger. What is more, there were no significant differences between BMSCs/β-TCP group and the group treated with autogenous bone and RME. This study further revealed that TEB was not only a feasible clinical approach for patients with alveolar cleft, but also a potential substituent of autogenous bone, and its combination with RME might be an alternative strategy for the therapy of alveolar cleft.

  4. Alveolar bone protective and hypoglycemic effects of systemic propolis treatment in experimental periodontitis and diabetes mellitus.

    Science.gov (United States)

    Aral, Cüneyt Asım; Kesim, Servet; Greenwell, Henry; Kara, Mehmet; Çetin, Aysun; Yakan, Birkan

    2015-02-01

    The aim of this study was to evaluate the efficacy of the anti-inflammatory effects of propolis on the systemic and local effects on experimental periodontitis and diabetes. Fifty-six Wistar rats were divided into seven groups: (1) negative-control (NC), (2) periodontitis (P), (3) diabetes (D), (4) diabetes+periodontitis (DP), (5) periodontitis+propolis (P-Pro), (6) diabetes+propolis (D-Pro), and (7) diabetes+periodontitis+propolis (DP-Pro). Periodontitis was induced by ligature placement and diabetes was induced by streptozotocin injection. Propolis (Pro) was administrated by oral gavage (100 mg/kg/day). On day 21, plasma was obtained for analysis and alveolar bone level was evaluated using histomorphometric analysis. Compared to NC the final blood glucose levels for D-Pro was not significantly different (P=.052), however, D, DP, and DP-Pro were significantly different. There were no statistically significant differences in blood glucose concentrations between P and P-Pro, between D and D-Pro, and between DP and DP-Pro. All groups showed significantly more alveolar bone loss compared with NC. A significant difference in bone loss was found between P and P-Pro, and DP and DP-Pro, however there was no difference between D and D-Pro. Plasma interleukin 1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and matrix metalloproteinase-8 (MMP-8) levels were not significantly different among groups. In conclusion, propolis reduced fasting blood glucose levels in diabetes. In addition, propolis might be beneficial as an adjunct treatment of diabetes associated periodontitis and periodontitis without diabetes.

  5. Interim endodontic therapy for alveolar socket bone regeneration of infected hopeless teeth prior to implant therapy.

    Science.gov (United States)

    Rass, Marwan Abou

    2010-01-01

    patients' dental care. When treated, these hopeless teeth served many preventive, biologic, and esthetic functions. The infections of the alveolar sockets were eliminated, the alveolar bone defects were repaired through normal bone regeneration, and sockets anatomies were maintained or restored. Furthermore, the patients were spared maxillary sinus surgery and the possible complications resulting from major GBR and GTR procedures. In summary, the interim treatment facilitated tooth extraction and immediate implant placement.

  6. 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.

  7. Twelve months of voluntary heavy alcohol consumption in male rhesus macaques suppresses intracortical bone remodeling.

    Science.gov (United States)

    Gaddini, Gino W; Grant, Kathleen A; Woodall, Andrew; Stull, Cara; Maddalozzo, Gianni F; Zhang, Bo; Turner, Russell T; Iwaniec, Urszula T

    2015-02-01

    Chronic heavy alcohol consumption is a risk factor for cortical bone fractures in males. The increase in fracture risk may be due, in part, to reduced bone quality. Intracortical (osteonal) bone remodeling is the principle mechanism for maintaining cortical bone quality. However, it is not clear how alcohol abuse impacts intracortical bone remodeling. This study investigated the effects of long-duration heavy alcohol consumption on intracortical bone remodeling in a non-human primate model. Following a 4-month induction period, male rhesus macaques (Macaca mulatta, n=21) were allowed to voluntarily self-administer water or alcohol (4% ethanol w/v) for 22h/d, 7 d/wk for 12months. Control monkeys (n=13) received water and an isocaloric maltose-dextrin solution. Tetracycline hydrochloride was administered orally 17 and 3days prior to sacrifice for determination of active mineralization sites. Animals in the alcohol group consumed 2.7±0.2g alcohol/kg/d (mean±SE) during the 12months of self-administration, resulting in a mean daily blood alcohol concentration of 77±9mg/dl from samples taken at 7h after the start of a daily session. However, blood alcohol concentration varied widely from day to day, with peak levels exceeding 250mg/dl, modeling a binge-drinking pattern of alcohol consumption. The skeletal response to alcohol was determined by densitometry, microcomputed tomography and histomorphometry. Significant differences in tibial bone mineral content, bone mineral density, and cortical bone architecture (cross-sectional volume, cortical volume, marrow volume, cortical thickness, and polar moment of inertia) in the tibial diaphysis were not detected with treatment. However, cortical porosity was lower (1.8±0.5 % versus 0.6±0.1 %, p=0.021) and labeled osteon density was lower (0.41±0.2/mm(2)versus 0.04±0.01/mm(2), premodeling. In concordance, plasma CTx was lower (2.5±0.3ng/ml versus 1.7±0.1ng/ml, p=0.028) in the alcohol group. These results suggest that

  8. A joined role of canopy and reversal cells in bone remodeling - Lessons from glucocorticoid-induced osteoporosis

    DEFF Research Database (Denmark)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Hauge, Ellen-Margrethe

    2015-01-01

    Successful bone remodeling demands that osteoblasts restitute the bone removed by osteoclasts. In human cancellous bone, a pivotal role in this restitution is played by the canopies covering the bone remodeling surfaces, since disruption of canopies in multiple myeloma, postmenopausal......- and glucocorticoid-induced osteoporosis is associated with the absence of progression of the remodeling cycle to bone formation, i.e. uncoupling. An emerging concept explaining this critical role of canopies is that they represent a reservoir of osteoprogenitors to be delivered to reversal surfaces....... In postmenopausal osteoporosis, this concept is supported by the coincidence between the absence of canopies and scarcity of cells on reversal surfaces together with abortion of the remodeling cycle. Here we tested whether this concept holds true in glucocorticoid-induced osteoporosis. A histomorphometric analysis...

  9. Correlation between radiographic analysis of alveolar bone density around dental implant and resonance frequency of dental implant

    Science.gov (United States)

    Prawoko, S. S.; Nelwan, L. C.; Odang, R. W.; Kusdhany, L. S.

    2017-08-01

    The histomorphometric test is the gold standard for dental implant stability quantification; however, it is invasive, and therefore, it is inapplicable to clinical patients. Consequently, accurate and objective alternative methods are required. Resonance frequency analysis (RFA) and digital radiographic analysis are noninvasive methods with excellent objectivity and reproducibility. To analyze the correlation between the radiographic analysis of alveolar bone density around a dental implant and the resonance frequency of the dental implant. Digital radiographic images for 35 samples were obtained, and the resonance frequency of the dental implant was acquired using Osstell ISQ immediately after dental implant placement and on third-month follow-up. The alveolar bone density around the dental implant was subsequently analyzed using SIDEXIS-XG software. No significant correlation was reported between the alveolar bone density around the dental implant and the resonance frequency of the dental implant (r = -0.102 at baseline, r = 0.146 at follow-up, p > 0.05). However, the alveolar bone density and resonance frequency showed a significant difference throughout the healing period (p = 0.005 and p = 0.000, respectively). Conclusion: Digital dental radiographs and Osstell ISQ showed excellent objectivity and reproducibility in quantifying dental implant stability. Nonetheless, no significant correlation was observed between the results obtained using these two methods.

  10. [Maxillary alveolar process bone plasty with the use of directional tissue regeneration and maxillary sinus bottom lifting operation].

    Science.gov (United States)

    Losev, V F

    2009-01-01

    There were shown technique and clinical examples of the use of directional tissue regeneration in cases of bone tissue deficit in distal parts maxilla. Clinical cases were described of maxillary sinus bottom lifting with simultaneous alveolar process widening and single stage implant installation.

  11. Radiographic evaluation of the effect of obesity on alveolar bone in rats with ligature-induced periodontal disease

    Directory of Open Access Journals (Sweden)

    do Nascimento CM

    2013-10-01

    Full Text Available Cassiane Merigo do Nascimento,1 Tiago Cassol,2 Fernanda Soares da Silva,3 Maria Lucia Bonfleur,4 Carlos Augusto Nassar,5 Patricia Oehlmeyer Nassar5 1Biologica Science and Health Center, State University of West Paraná (UNIOESTE, Cascavel, Paraná, Brazil; 2State University of West Paraná (UNIOESTE, Cascavel, Paraná, Brazil; Department of 3Pharmacy, 4Fisiology, 5Periodontology, Dental School, State University of West Paraná (UNIOESTE, Cascavel, Paraná, Brazil Abstract: There is evidence that the lack of metabolic control of obese patients may accelerate periodontitis. The aim of this study was to evaluate radiographically the effect of cafeteria-diet-induced obesity on alveolar bone loss in rats subjected to periodontal disease. Twenty male Wistar rats were randomly divided into four groups: 1 control group, 2 control and ligature group; 3 cafeteria group; and 4 cafeteria and ligature group. The animals were evaluated for obesity and euthanized, and the mandible of each rat was removed to perform a radiographic evaluation of alveolar bone loss and its effect on diet-induced obesity. The results showed greater alveolar bone loss in the mice in Group 4 (P<0.01. Thus, we concluded that obese mice, on average, showed greater radiographic evidence of alveolar bone loss than mice undergoing induction of obesity. Keywords: periodontal disease, radiography, obesity

  12. 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.

  13. 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.

  14. Impact of targeted PPAR gamma disruption on bone remodeling

    Science.gov (United States)

    Peroxisome proliferator-activated receptor gamma (PPAR gamma), known as the master regulator of adipogenesis, has been regarded as a promising target for new anti-osteoporosis therapy due to its role in regulating bone marrow mesenchymal stem/progenitor cell (BMSC) lineage commitment. However, the p...

  15. 4D confocal microscopy for visualisation of bone remodelling

    NARCIS (Netherlands)

    Konijn, GA; Vardaxis, NJ; Boon, ME; Kok, LP; Rietveld, DC; SCHUT, JJ

    1996-01-01

    Until recently it was very time consuming and difficult to make three-dimensional (3D) images of newly formed bone. With the advent of confocal technologies and increased computer power 3D imaging is greatly facilitated. In this paper we demonstrate that enhanced confocal visualisation of newly form

  16. Interleukin-33 and RANK-L Interplay in the Alveolar Bone Loss Associated to Periodontitis

    Science.gov (United States)

    Lapérine, Olivier; Cloitre, Alexandra; Caillon, Jocelyne; Huck, Olivier; Bugueno, Isaac Maximiliano; Pilet, Paul; Sourice, Sophie; Le Tilly, Elodie; Palmer, Gaby; Davideau, Jean-Luc; Geoffroy, Valérie; Guicheux, Jérôme; Beck-Cormier, Sarah; Lesclous, Philippe

    2016-01-01

    Introduction Chronic Periodontitis (CP) is an inflammatory disease of bacterial origin that results in alveolar bone destruction. Porphyromonas gingivalis (Pg), one of the main periopathogens, initiates an inflammatory cascade by host immune cells thereby increasing recruitment and activity of osteoclasts, the bone resorbing cells, through enhanced production of the crucial osteoclastogenic factor, RANK-L. Antibodies directed against some cytokines (IL-1β, IL-6 and TNF-α) failed to exhibit convincing therapeutic effect in CP. It has been suggested that IL-33, could be of interest in CP. Objective the present study aims to analyze whether and how IL-33 and RANK-L and/or their interplay are involved in the bone destruction associated to CP. Material and Methods mRNAs and protein expressions of IL-33 and RANK-L were analyzed in healthy and CP human gingival samples by immunohistochemistry (IHC) and RT-qPCR. Murine experimental periodontitis (EP) was induced using Pg infected ligature and Pg free ligature around the first maxillary molar. Alveolar bone loss was recorded by μCT. Mouse gingival explants were stimulated for 24 hours with IL-33 and RANK-L mRNA expression investigated by RT-qPCR. Human oral epithelial cells were infected by Pg for 6, 12; 24 hours and IL-33 and RANK-L mRNA expressions were analyzed by RT-qPCR. Results IL-33 is overexpressed in gingival epithelial cells in human affected by CP as in the murine EP. In human as in murine gingival cells, RANK-L was independently induced by Pg and IL-33. We also showed that the Pg-dependent RANK-L expression in gingival epithelial cells occured earlier than that of IL-33. Conclusion Our results evidence that IL-33 overexpression in gingival epithelial cells is associated with CP and may trigger RANK-L expression in addition to a direct effect of Pg. Finally, IL-33 may act as an extracellular alarmin (danger signal) showing proinflammatory properties in CP perpetuating bone resorption induced by Pg infection

  17. Effects of diazepam on orthodontic tooth movement and alveolar bone cAMP levels in cats.

    Science.gov (United States)

    Burrow, S J; Sammon, P J; Tuncay, O C

    1986-08-01

    Cyclic AMP has been suggested as a possible intracellular mediator in bone remodeling during tooth movement. Accordingly, an increase in the level of this nucleotide should result in faster tooth movement. Breakdown of cAMP was inhibited by administration of diazepam in eight cats undergoing orthodontic tooth movement; another matched group of eight animals served as controls. Orthodontic appliances consisted of coil springs stretching between the right side maxillary and mandibular canines and third premolars. The data for tooth movement and cAMP concentrations were analyzed by repeated measures factorial analyses of variance. The results indicated that administration of diazepam increased the rate of tooth movement at P less than 0.0005 and, interestingly, although diazepam had no effect on undisturbed tissues, it lowered the cAMP levels in the periodontal tissues of orthodontically moved teeth at P less than 0.01. On the basis of these results, it was concluded that the concentration of cAMP did not correlate with bone remodeling in this model and perhaps should not be used as an index of periodontal-tissue response during orthodontic tooth movement.

  18. Translational Research: Palatal-derived Ecto-mesenchymal Stem Cells from Human Palate: A New Hope for Alveolar Bone and Cranio-Facial Bone Reconstruction.

    Science.gov (United States)

    Grimm, Wolf Dieter; Dannan, Aous; Giesenhagen, Bernd; Schau, Ingmar; Varga, Gabor; Vukovic, Mark Alexander; Sirak, Sergey Vladimirovich

    2014-05-01

    The management of facial defects has rapidly changed in the last decade. Functional and esthetic requirements have steadily increased along with the refinements of surgery. In the case of advanced atrophy or jaw defects, extensive horizontal and vertical bone augmentation is often unavoidable to enable patients to be fitted with implants. Loss of vertical alveolar bone height is the most common cause for a non primary stability of dental implants in adults. At present, there is no ideal therapeutic approach to cure loss of vertical alveolar bone height and achieve optimal pre-implantological bone regeneration before dental implant placement. Recently, it has been found that specific populations of stem cells and/or progenitor cells could be isolated from different dental resources, namely the dental follicle, the dental pulp and the periodontal ligament. Our research group has cultured palatal-derived stem cells (paldSCs) as dentospheres and further differentiated into various cells of the neuronal and osteogenic lineage, thereby demonstrating their stem cell state. In this publication will be shown whether paldSCs could be differentiated into the osteogenic lineage and, if so, whether these cells are able to regenerate alveolar bone tissue in vivo in an athymic rat model. Furthermore, using these data we have started a proof of principle clinical- and histological controlled study using stem cell-rich palatal tissues for improving the vertical alveolar bone augmentation in critical size defects. The initial results of the study demonstrate the feasibility of using stem cell-mediated tissue engineering to treat alveolar bone defects in humans.

  19. Multiscale approach for bone remodeling simulation based on finite element and neural network computation

    CERN Document Server

    Hambli, Ridha

    2011-01-01

    The aim of this paper is to develop a multiscale hierarchical hybrid model based on finite element analysis and neural network computation to link mesoscopic scale (trabecular network level) and macroscopic (whole bone level) to simulate bone remodelling process. Because whole bone simulation considering the 3D trabecular level is time consuming, the finite element calculation is performed at macroscopic level and a trained neural network are employed as numerical devices for substituting the finite element code needed for the mesoscale prediction. The bone mechanical properties are updated at macroscopic scale depending on the morphological organization at the mesoscopic computed by the trained neural network. The digital image-based modeling technique using m-CT and voxel finite element mesh is used to capture 2 mm3 Representative Volume Elements at mesoscale level in a femur head. The input data for the artificial neural network are a set of bone material parameters, boundary conditions and the applied str...

  20. Stress Distribution on Short Implants at Maxillary Posterior Alveolar Bone Model With Different Bone-to-Implant Contact Ratio: Finite Element Analysis.

    Science.gov (United States)

    Yazicioglu, Duygu; Bayram, Burak; Oguz, Yener; Cinar, Duygu; Uckan, Sina

    2016-02-01

    The aim of this study was to evaluate the stress distribution of the short dental implants and bone-to-implant contact ratios in the posterior maxilla using 3-dimensional (3D) finite element models. Two different 3D maxillary posterior bone segments were modeled. Group 1 was composed of a bone segment consisting of cortical bone and type IV cancellous bone with 100% bone-to-implant contact. Group 2 was composed of a bone segment consisting of cortical bone and type IV cancellous bone including spherical bone design and homogenous tubular hollow spaced structures with 30% spherical porosities and 70% bone-to-implant contact ratio. Four-millimeter-diameter and 5-mm-height dental implants were assumed to be osseointegrated and placed at the center of the segments. Lateral occlusal bite force (300 N) was applied at a 25° inclination to the implants long axis. The maximum von Mises stresses in cortical and cancellous bones and implant-abutment complex were calculated. The von Mises stress values on the implants and the cancellous bone around the implants of the 70% bone-to-implant contact group were almost 3 times higher compared with the values of the 100% bone-to-implant contact group. For clinical reality, use of the 70% model for finite element analysis simulation of the posterior maxilla region better represents real alveolar bone and the increased stress and strain distributions evaluated on the cortical and cancellous bone around the dental implants.

  1. Chronic Multifocal Inflammation of the Alveolar Bone Mimicking Malignancy: A Case Report

    Directory of Open Access Journals (Sweden)

    Shahidi Sh.

    2012-03-01

    Full Text Available ronic inflammation of the alveolar bone is a great clinical and radiologic mimic, which merits recognition by the clinician and pathologist. The patient can thus be reassured of the proper early treatment and a favorable prognosis. Occasionally, it is difficult to differentiate inflammatory lesions from malign-ant tumors. The aim of this report is to present a case with an inflammatory lesion mimicking malignant condition.We report a 19-year-old male complaining of rapid onset gingival swelling of the right side of both jaws and looseness of the right upper molar teeth in 20 days. Based on the acute onset of the gingival hyperplasia, severe looseness of the affected teeth especially in the maxilla, and the patient's age, multifocal rapid growing malignant condition was not ruled out. The lesion was misdiagnosed as a malignant condition by clinical and radiographic examination. The whole body bone scan showed no significant increased uptake in the right oral cavity compatible with no active bony pathology. The surgical pathology findings of the lesion showed severe chronic inflammation with surface epithelial hyperplasia.The initial diagnosis of the lesion was malignant condition but it was ruled out by bone scan and histological appearance.

  2. Comparative effects of riboflavin, nicotinamide and folic acid on alveolar bone loss: A morphometric and histopathologic study in rats

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    Akpınar Aysun

    2016-01-01

    Full Text Available Introduction. Periodontitis is a chronic inflammatory and osteolytic disease. Vitamin B complex is a class of water-soluble vitamins that play important roles in cell metabolism. Objective. The aim of this study was to evaluate the effects of riboflavin (RBF, nicotinamide (NA, and folic acid (FA on alveolar bone loss in experimental periodontitis rat model. Methods. Sixty-four male Wistar rats were randomly divided into the following eight groups: Control, Ligated, RBF50 (RBF, 50 mg/kg daily, NA50 (NA, 50 mg/kg daily, FA50 (FA, 50 mg/kg daily, RBF100 (RBF, 100 mg/kg daily, NA100 (NA, 100 mg/kg daily, and FA100 (FA, 100 mg/kg daily. Periodontitis was induced using silk ligature around the right first mandibular molar. After 11 days the rats were sacrificed. Mandible and serum samples were collected. Changes in alveolar bone levels were measured clinically, and periodontal tissues were examined histopathologically. Serum IL-1β (pg/ml levels were analyzed by using ELISA. Results. Mean alveolar bone loss in the mandibular first molar tooth revealed to be significantly lower in RBF100 group than in the Control group. In the Ligated group, alveolar bone loss was significantly higher than in all other groups. The ratio of presence of inflammatory cell infiltration in the Ligated group was significantly higher than in the Control group. The differences in the serum IL-1β levels between the groups were not statistically significant. Osteoclasts that were observed in the Ligated group were significantly higher than those of the Control and FA100 groups. The osteoblastic activity in the Ligated group, RBF100, and NA100 groups were shown to be significantly higher than those in the Control group. Conclusion. This study has demonstrated that systemic administration of RBF, NA, and FA in different dosages (50-100 mg/kg reduced alveolar bone loss in periodontal disease in rats.

  3. Platelet-rich fibrin/aspirin complex promotes alveolar bone regeneration in periodontal defect in rats.

    Science.gov (United States)

    Du, J; Mei, S; Guo, L; Su, Y; Wang, H; Liu, Y; Zhao, Z; Wang, S; Liu, Y

    2017-09-01

    The efficacy and outcomes of aspirin in local defects and the use of platelet-rich fibrin (PRF) in periodontal defects were investigated. Whether the PRF/aspirin complex is a suitable scaffold and delivery system to carry sustained-release aspirin/salicylic acid to promote periodontal bone regeneration was determined. PRF and PRF/aspirin complex were prepared. The concentrations of aspirin/salicylic acid released from the PRF/aspirin complex were calculated at 37°C. Periodontal ligament mesenchymal cells were cultured on six-well plates with PRF or PRF/aspirin complex gel to analyze proliferation and migration. The alveolar bone between the inferior buccal mesial root and anterior buccal distal root of the first maxillary molar was removed in 15 rats randomly divided into three groups: no treatment, PRF or PRF/aspirin complex. Twelve weeks post-transplantation, 2D/3D micro-computed tomography and histomorphometric technique were used for quantitative analyses. The PRF/aspirin complex provided a sustained-release aspirin/salicylic acid. Peak concentrations occurred 4 hours after transplantation and were sustained to 48 hours at 37°C; the total concentration of released aspirin/salicylic acid was 83.5 mg/mL, respectively. The sustained-release promoted the proliferation and migration of periodontal ligament mesenchymal cells. Micro-computed tomography and histological data showed that both the PRF and PRF/aspirin complex enhanced periodontal bone formation (P<.05). Moreover, the new bone formation was two times greater in the PRF/aspirin complex group than the PRF group. Aspirin/salicylic acid could be sustained-released from PRF/aspirin complex, which could inhibit inflammation and improve the function of mesenchymal cells. The data might provide a new safe and easy clinical therapeutic strategy to promote periodontal bone reparation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Trabecular bone structure and strength - remodelling and repair

    DEFF Research Database (Denmark)

    Mosekilde, Lis; Ebbesen, Ebbe Nils; Erikstrup, Lise Tornvig

    2000-01-01

    relationship is based on the fact that trabecular bone is a porous material. To date, it has not been possible to determine or quantify the influence other factors may have in determining the strength of a loadbearing trabecular network. However, it is known that with age: 1) There is a loss of connectivity...... through osteoclastic perforations of horizontal struts. 2) There is an increase in anisotropy - again due to loss of horizontal struts, and perhaps also due to micro-modelling drift or to thickening of some vertical trabeculae. 3) The changes in the network can lead to the slenderness ratio between...... can never be isolated in vivo, other factors need to be investigated: The interplay between the cortical shell and the trabecular network; transmission of load; the interplay between soft tissues (cartilage, connective tissue, muscle) and bone; the shock absorbing capacity of the discs...

  5. Evaluation of bone remodeling around single dental implants of different lengths: a mechanobiological numerical simulation and validation using clinical data.

    Science.gov (United States)

    Sotto-Maior, Bruno Salles; Mercuri, Emílio Graciliano Ferreira; Senna, Plinio Mendes; Assis, Neuza Maria Souza Picorelli; Francischone, Carlos Eduardo; Del Bel Cury, Altair Antoninha

    2016-01-01

    Algorithmic models have been proposed to explain adaptive behavior of bone to loading; however, these models have not been applied to explain the biomechanics of short dental implants. Purpose of present study was to simulate bone remodeling around single implants of different lengths using mechanoregulatory tissue differentiation model derived from the Stanford theory, using finite elements analysis (FEA) and to validate the theoretical prediction with the clinical findings of crestal bone loss. Loading cycles were applied on 7-, 10-, or 13-mm-long dental implants to simulate daily mastication and bone remodeling was assessed by changes in the strain energy density of bone after a 3, 6, and 12 months of function. Moreover, clinical findings of marginal bone loss in 45 patients rehabilitated with same implant designs used in the simulation (n = 15) were computed to validate the theoretical results. FEA analysis showed that although the bone density values reduced over time in the cortical bone for all groups, bone remodeling was independent of implant length. Clinical data showed a similar pattern of bone resorption compared with the data generated from mathematical analyses, independent of implant length. The results of this study showed that the mechanoregulatory tissue model could be employed in monitoring the morphological changes in bone that is subjected to biomechanical loads. In addition, the implant length did not influence the bone remodeling around single dental implants during the first year of loading.

  6. Estudio histológico comparativo de la reparación ósea entre hueso alveolar y extra-alveolar en los cerdos sometidos a osteotomía con alta y baja velocidad, con refrigeración líquida Comparative study of bone repair between alveolar and extra-alveolar bone in pigs subjected to osteotomy at low speed and high speed with liquid refrigeration

    Directory of Open Access Journals (Sweden)

    Henrique José Baldo de Toledo

    2012-03-01

    Full Text Available Introducción: Teniendo en cuenta que el proceso de reparación ósea en los cerdos se muestra en una mayor proximidad entre las variables histológicas estudiadas en comparación con otros modelos biológicos, el presente estudio tenía como objetivo evaluar el proceso histológico de la reparación ósea de osteotomías realizadas en huesos alveolares y extra-alveolar, utilizando instrumentos rotatorios con refrigeración líquida. Material y método: Dieciocho cerdos Large White con peso comprendido entre 20 y 25Kg fueron divididos en tres grupos de seis animales cada uno, con cada grupo formado por tres animales para evaluar la reparación de osteotomías con baja y alta velocidades en el hueso alveolar y tres en área extra-alveolar en los períodos de estudio de 7, 14 y 28 días. Resultados: Se observó que en el hueso alveolar en los tiempos post-operatorio de 14 y 28 días, los mejores resultados de reparación fueron en las osteotomías realizadas con baja velocidad, mientras que en el período post-operatorio de siete días, los resultados con alta velocidad fueron ligeramente mejores tanto en áreas alveolares como extra-alveolares. Para la metodología utilizada, no se encontraron diferencias estadísticamente significativas en el proceso de reparación ósea alveolar y extra-alveolar. Conclusiones: El proceso de reparación, por medio de análisis microscópico en la región alveolar y extra-alveolar, son similares con mejores resultados observados en osteotomías hechas con taladros en baja velocidad en los tiempos de catorce y veintiocho días y en el post-operatorio de siete días, los resultados con taladros de alta velocidad y la refrigeración fueron ligeramente mejores. Los trabajos de investigación utilizando cerdos como modelo animal son perfectamente viables.Introduction: Taking into account the bone repair process in pigs has shown a greater similarity among the histological variables studied compared to other biological

  7. The role of osteocalcin in the endocrine cross-talk between bone remodelling and energy metabolism.

    Science.gov (United States)

    Ducy, P

    2011-06-01

    Bone remodelling, which maintains bone mass constant during adulthood, is an energy-demanding process. This, together with the observation that the adipocyte-derived hormone leptin is a major inhibitor of bone remodelling, led to the hypothesis that bone cells regulate energy metabolism through an endocrine mechanism. Studies to test this hypothesis identified osteocalcin, a hormone secreted by osteoblasts, as a positive regulator of insulin secretion, insulin resistance and energy expenditure. Remarkably, insulin signalling in osteoblasts is a positive regulator of osteocalcin production and activation via its ability to indirectly enhance bone resorption by osteoclasts. In contrast, leptin is a potent inhibitor of osteocalcin function through its effect on the sympathetic tone. Hence, osteocalcin is part of a complex signalling network between bone and the organs more classically associated with the regulation of energy homeostasis, such as the pancreas and adipose tissue. This review summarises the molecular and cellular bases of the present knowledge on osteocalcin biology and discusses the potential relevance of osteocalcin to human metabolism and pathology.

  8. [Effect of dosed diet restriction on physiological remodeling and bioelectric properties of bone].

    Science.gov (United States)

    Levashov, M I; Ianko, R V; Chaka, E G; Safonov, S L

    2014-07-01

    The effect of dosed diet restriction on the physiological remodeling and bioelectric properties of bone tissue was studied in 48 male Wistar rats 3- and 18-months of age. The rate of bone tissue apposition was studied by the dynamic histomorphometry method (intravital tetracycline labeling). Electric potentials on the periosteal surface of the freshly isolated femurs were recorded. The magnitude of dielectric loss factor was determined to assess the quality of bone tissue. The control rats received a standard diet. The experimental rats received a limited diet (60 % of the standard mass) for 28 days. The magnitude and rate of the bone tissue apposition on the endosteal and periosteal surface of the tibia were less by 38.4% and 122.7% respectively in experimental rats after dosed diet restriction. Electric potential in the metaphyseal-epiphyseal growth zones of the femur was 29.7% lower, and the dielectric loss factor increased by 15.8%. The bone tissue apposition rate and the electric potential magnitude were increased 10 days after completion of the dosed diet restriction. The magnitude of the dielectric loss factor decreased after returning to the standard diet. Key words: dosed diet restriction, bone, remodelling, bioelectric properties.

  9. Preparation and Evaluations of Mangiferin-Loaded PLGA Scaffolds for Alveolar Bone Repair Treatment Under the Diabetic Condition.

    Science.gov (United States)

    Li, Hao; Liao, Hongbing; Bao, Chongyun; Xiao, Yu; Wang, Qi

    2017-02-01

    The aim of the present study was to prepare and evaluate a sustained-release mangiferin scaffold for improving alveolar bone defect repair in diabetes. Mangiferin-loaded poly(D,L-lactide-co-glycolide) (PLGA) scaffolds were prepared using a freeze-drying technique with ice particles as the porogen material. The produced scaffolds were examined using a scanning electron microscope (SEM). Drug content and drug release were detected using a spectrophotometer. Degradation behaviors were monitored as a measure of weight loss and examined using SEM. Then, the scaffolds were incubated with rat bone marrow stromal cells under the diabetic condition in vitro, and cell viability was assessed using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Afterward, the scaffolds were implanted into alveolar bone defects of diabetic rats, and bone repair was examined using hematoxylin and eosin staining. The fabricated scaffolds showed porous structures, with average pore size range from 111.35 to 169.45 μm. A higher PLGA concentration led to decreased average pore size. A lower PLGA concentration or a higher mangiferin concentration resulted in increased drug content. The prepared scaffolds released mangiferin in a sustained manner with relatively low initial burst during 10 weeks. Their degradation ratios gradually increased as degradation proceeded. The mangiferin-loaded scaffolds attenuated cell viability decrease under the diabetic condition in vitro. Moreover, they increased histological scorings of bone regeneration and improved delayed alveolar bone defect healing in diabetic rats. These results suggest that the produced mangiferin-loaded scaffolds may provide a potential approach in the treatment of impaired alveolar bone healing in diabetes.

  10. A Comparison of Panoramic, Periapical and Bite Wing Radiographies in Evaluation of Alveolar Bone Loss in Periodiontitis

    Directory of Open Access Journals (Sweden)

    A Haerian Ardakani

    2007-07-01

    Full Text Available Introduction: The height of the alveolar bone, is normally maintained by equilibrium between bone formation and bone resorption, but in periodontal disease more destruction or lack of bone formation will reduce the alveolar bone height. However the radiography is important in diagnosis, treatment plan and detection of quality and quantity of the alveolar bone; although the type of radiography is more important. The purpose of this study is the comparison between panaromic, P.A (Parallel, Bite Wing radiographs in diagnosis of periodontitis. Methods: This study was descriptive cross-Sectional study Periapical (PA, Bitewing (B.W & Panoramic radiographic images in 32 pationent 13 male and 19 female with moderate to advanced periodontitis (mean age 38 year were taken before surgical treatment. Actual hight of defect were measured by a William's probe during surgery, the distance between cemento enamel junction (CEJ and alveolar crest were measured on radiographs using a digital vernie scale as will as. Actual measurements were compared with values taken from panoramic PA, B.W radiographs. For Data analysis Paired t test was used. Results: A total of 314 linear distances from the panoramic PA , B.W, and CEJ/BL were measured. The mean difference between panoramic and actual Measurements (0.115 and 0.28 P=(0.24-0.07, were not satistically significant (P> 0.05. The mean difference between P.A and actual measurements (0.279-0.498 P=(0.0001-0.004 showed a satistically significant difference (P< 0.05. The mean deference between BW and actual Measurements (0.576-0.613 P=(0.24-0.07 were satistically significant (P<0.05. Conclusion: Although, all forms of radiographic images showed agreement in detection of periodontal bone loss, the accuracy of panoramic radiographs was more than PA & BW radiographs'. Specially when the magnification was adjusted in panoramic radiography.

  11. Effect of platelet-rich plasma (PRP) concentration on the viability and proliferation of alveolar bone cells: an in vitro study.

    Science.gov (United States)

    Choi, B-H; Zhu, S-J; Kim, B-Y; Huh, J-Y; Lee, S-H; Jung, J-H

    2005-06-01

    Previous studies have shown that a combination of platelet-rich plasma (PRP) and autogenous bone graft can increase the rate of osteogenesis and enhance bone formation qualitatively. However, contradictory results were reported in a recent animal study. In order to clarify this inconsistency, this study examined the influence of the PRP concentrations on the viability and proliferation of alveolar bone cells in vitro. Bone cells obtained from the alveolar bone chips were exposed to various PRP concentrations. After a culture period of 7 days, cellular viability and proliferation were evaluated by counting the number of cells and a MTT assay. The results showed that the viability and proliferation of alveolar bone cells were suppressed by high PRP concentrations, but were stimulated by low PRP concentrations (1-5%). These in vitro results support the view that variations in the PRP concentrations might influence the bone formation within the PRP-treated bone grafts.

  12. High-Frequency, Low-Intensity Pulsed Ultrasound Enhances Alveolar Bone Healing of Extraction Sockets in Rats: A Pilot Study.

    Science.gov (United States)

    Kang, Kyung Lhi; Kim, Eun-Cheol; Park, Joon Bong; Heo, Jung Sun; Choi, Yumi

    2016-02-01

    Most studies of the beneficial effects of low-intensity pulsed ultrasound (LIPUS) on bone healing have used frequencies between 1.0 and 1.5 MHz. However, after consideration of ultrasound wave characteristics and depth of target tissue, higher-frequency LIPUS may have been more effective on superficially positioned alveolar bone. We investigated this hypothesis by applying LIPUS (frequency, 3.0 MHz; intensity, 30 mW/cm(2)) on shaved right cheeks over alveolar bones of tooth extraction sockets in rats for 10 min/d for 2 wk after tooth extraction; the control group (left cheek of the same rats) did not receive LIPUS treatment. Compared with the control group, the LIPUS group manifested more new bone growth inside the sockets on histomorphometric analysis (maximal difference = 2.5-fold on the seventh day after extraction) and higher expressions of osteogenesis-related mRNAs and proteins than the control group did. These findings indicate that 3.0-MHz LIPUS could enhance alveolar bone formation and calcification in rats.

  13. Therapeutic Effects of Melatonin on Alveolar Bone Resorption After Experimental Periodontitis in Rats: A Biochemical and Immunohistochemical Study.

    Science.gov (United States)

    Arabacı, Taner; Kermen, Eda; Özkanlar, Seçkin; Köse, Oğuz; Kara, Adem; Kızıldağ, Alper; Duman, Şuayip Burak; Ibişoğlu, Ebru

    2015-07-01

    The present study aims to investigate the effects of systemic melatonin administration on alveolar bone resorption in experimental periodontitis in rats. Twenty-four male Sprague-Dawley rats were divided into three groups (control, experimental periodontitis [Ped], and experimental periodontitis treated with melatonin [Mel-Ped]). For periodontitis induction, first molars were ligatured submarginally for 4 weeks. After ligature removal, rats in the Mel-Ped group were treated with a daily single dose of 10 mg/kg body weight melatonin for 15 consecutive days. At the end of the study, intracardiac blood samples and mandible tissues were obtained for histologic, biochemical, and radiographic analysis. Serum markers related to bone turnover, calcium, phosphorus, bone alkaline phosphatase (b-ALP), and terminal C telopeptide of collagen Type I (CTX) were analyzed. Myeloperoxidase levels were determined in gingival tissue homogenates, and receptor activator of nuclear factor-kappa B ligand (RANKL) activation was analyzed in the mandible samples stereologically. Alveolar bone loss was also evaluated radiographically in the mandible samples of each group. Melatonin treatment decreased serum CTX levels and increased b-ALP levels. Serum calcium and phosphorus levels were not statistically different among groups (P >0.05). Alveolar bone resorption and myeloperoxidase activity were statistically higher in the Ped group compared to the Mel-Ped group (P periodontal healing in an experimental periodontitis rat model.

  14. Resveratrol prevents alveolar bone loss in an experimental rat model of periodontitis.

    Science.gov (United States)

    Bhattarai, Govinda; Poudel, Sher Bahadur; Kook, Sung-Ho; Lee, Jeong-Chae

    2016-01-01

    Resveratrol is an antioxidant and anti-inflammatory polyphenol. Periodontitis is induced by oral pathogens, where a systemic inflammatory response accompanied by oxidative stress is the major event initiating disease. We investigated how resveratrol modulates cellular responses and the mechanisms related to this modulation in lipopolysaccharide (LPS)-stimulated human gingival fibroblasts (hGFs). We also explored whether resveratrol protects rats against alveolar bone loss in an experimental periodontitis model. Periodontitis was induced around the first upper molar of the rats by applying ligature infused with LPS. Stimulating hGFs with 5μg/ml LPS augmented the expression of cyclooxygenase-2, matrix metalloproteinase (MMP)-2, MMP-9, and Toll-like receptor-4. LPS treatment also stimulated the production of reactive oxygen species (ROS) and the phosphorylation of several protein kinases in the cells. However, the expression of heme oxygenase-1 (HO-1) and nuclear factor-E2 related factor 2 (Nrf2) was inhibited by the addition of LPS. Resveratrol treatment almost completely inhibited all of these changes in LPS-stimulated cells. Specifically, resveratrol alone augmented HO-1 induction via Nrf2-mediated signaling. Histological and micro-CT analyses revealed that administration of resveratrol (5mg/kg body weight) improved ligature/LPS-mediated alveolar bone loss in rats. Resveratrol also attenuated the production of inflammation-related proteins, the formation of osteoclasts, and the production of circulating ROS in periodontitis rats. Furthermore, resveratrol suppressed LPS-mediated decreases in HO-1 and Nrf2 levels in the inflamed periodontal tissues. Collectively, our findings suggest that resveratrol protects rats from periodontitic tissue damage by inhibiting inflammatory responses and by stimulating antioxidant defense systems. The aims of this study were to investigate how resveratrol modulates cellular responses and the mechanisms related to this modulation in

  15. Novel bone substitute material in alveolar bone healing following tooth extraction: an experimental study in sheep.

    Science.gov (United States)

    Liu, Jinyi; Schmidlin, Patrick R; Philipp, Alexander; Hild, Nora; Tawse-Smith, Andrew; Duncan, Warwick

    2016-07-01

    Electrospun cotton wool-like nanocomposite (ECWN) is a novel synthetic bone substitute that incorporates amorphous calcium phosphate nanoparticles into a biodegradable synthetic copolymer poly(lactide-co-glycolide). The objectives of this study were to develop a tooth extraction socket model in sheep for bone graft research and to compare ECWN and bovine-derived xenograft (BX) in this model. Sixteen cross-bred female sheep were used. Bilateral mandibular premolars were extracted atraumatically. Second and third premolar sockets were filled (Latin-square allocation) with BX, ECWN or left unfilled. Resorbable collagen membranes were placed over BX and selected ECWN grafted sockets. Eight sheep per time period were sacrificed after 8 and 16 weeks. Resin-embedded undemineralised sections were analysed for descriptive histology and histomorphometric analyses. At 8 weeks, there were with no distinct differences in healing among the different sites. At 16 weeks, osseous healing followed a fine trabecular pattern in ECWN sites. Non-grafted sites showed thick trabeculae separated by large areas of fibrovascular connective tissue. In BX grafted sites, xenograft particles were surrounded by newly formed bone or fibrovascular connective tissue. There were no statistically significant differences in bone formation across the four groups. However, ECWN sites had significantly less residual graft material than BX sites at 16 weeks (P = 0.048). This first description of a tooth extraction socket model in sheep supports the utility of this model for bone graft research. The results of this study suggested that the novel material ECWN did not impede bone ingrowth into sockets and showed evidence of material resorption. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Roles of the kidney in the formation, remodeling and repair of bone.

    Science.gov (United States)

    Wei, Kai; Yin, Zhiwei; Xie, Yuansheng

    2016-06-01

    The relationship between the kidney and bone is highly complex, and the kidney plays an important role in the regulation of bone development and metabolism. The kidney is the major organ involved in the regulation of calcium and phosphate homeostasis, which is essential for bone mineralization and development. Many substances synthesized by the kidney, such as 1,25(OH)2D3, Klotho, bone morphogenetic protein-7, and erythropoietin, are involved in different stages of bone formation, remodeling and repair. In addition, some cytokines which can be affected by the kidney, such as osteoprotegerin, sclerostin, fibroblast growth factor -23 and parathyroid hormone, also play important roles in bone metabolism. In this paper, we summarize the possible effects of these kidney-related cytokines on bone and their possible mechanisms. Most of these cytokines can interact with one another, constituting an intricate network between the kidney and bone. Therefore, kidney diseases should be considered among patients presenting with osteodystrophy and disturbances in bone and mineral metabolism, and treatment for renal dysfunction may accelerate their recovery.

  17. Interdental alveolar bone density in bruxers, mild bruxers, and non-bruxers affected by orthodontia and impaction as influencing factors.

    Directory of Open Access Journals (Sweden)

    Shereen Shokry

    2015-12-01

    Full Text Available Aim: To assess the interdental alveolar bone density within specific regions of interest in the mandible of bruxers, mild bruxers and non-bruxers in absence or presence of influencing factors, such as orthodontia and impaction. Materials and methods: The study consisted of 104 subjects (64 bruxers and 40 controls from the female students in the Faculty of Dentistry. Students were classified into bruxers, non-bruxers, and mild bruxers. The presence of modifying factors, such as impacted mandibular third molars and/or current or recent orthodontic treatment were identified. Panoramic radiographs were obtained, and the mean bone density values of interdental alveolar bone were measured using ImageJ software. Results: Non-bruxers had the highest mean bone density in all measured regions. The mesial aspect of the second premolar was an area of higher mean bone density in bruxers and in mild bruxers, compared to non-bruxers. In the presence of orthodontic treatment, the mean bone density in non-bruxers surpassed that of bruxers and mild bruxers. Conclusion: Bruxism, whether mild or severe decreased the interdental mean bone density in the studied regions of interest. The presence of influencing factors affected the interdental mean bone density.

  18. Moderate-intensity rotating magnetic fields do not affect bone quality and bone remodeling in hindlimb suspended rats.

    Directory of Open Access Journals (Sweden)

    Da Jing

    Full Text Available Abundant evidence has substantiated the positive effects of pulsed electromagnetic fields (PEMF and static magnetic fields (SMF on inhibiting osteopenia and promoting fracture healing. However, the osteogenic potential of rotating magnetic fields (RMF, another common electromagnetic application modality, remains poorly characterized thus far, although numerous commercial RMF treatment devices have been available on the market. Herein the impacts of RMF on osteoporotic bone microarchitecture, bone strength and bone metabolism were systematically investigated in hindlimb-unloaded (HU rats. Thirty two 3-month-old male Sprague-Dawley rats were randomly assigned to the Control (n = 10, HU (n = 10 and HU with RMF exposure (HU+RMF, n = 12 groups. Rats in the HU+RMF group were subjected to daily 2-hour exposure to moderate-intensity RMF (ranging from 0.60 T to 0.38 T at 7 Hz for 4 weeks. HU caused significant decreases in body mass and soleus muscle mass of rats, which were not obviously altered by RMF. Three-point bending test showed that the mechanical properties of femurs in HU rats, including maximum load, stiffness, energy absorption and elastic modulus were not markedly affected by RMF. µCT analysis demonstrated that 4-week RMF did not significantly prevent HU-induced deterioration of femoral trabecular and cortical bone microarchitecture. Serum biochemical analysis showed that RMF did not significantly change HU-induced decrease in serum bone formation markers and increase in bone resorption markers. Bone histomorphometric analysis further confirmed that RMF showed no impacts on bone remodeling in HU rats, as evidenced by unchanged mineral apposition rate, bone formation rate, osteoblast numbers and osteoclast numbers in cancellous bone. Together, our findings reveal that RMF do not significantly affect bone microstructure, bone mechanical strength and bone remodeling in HU-induced disuse osteoporotic rats. Our study indicates

  19. A prospective randomised study of periprosthetic femoral bone remodeling using four different bearings in hybrid total hip arthroplasty

    DEFF Research Database (Denmark)

    Zerahn, Bo; Borgwardt, Lotte; Ribel-Madsen, Søren

    2011-01-01

    Abstract: We performed a study to assess whether different bearing materials have an impact on femoral bone remodeling within the first four years after a hybrid total hip arthroplasty. 205 of 300 patients were available for 4 years follow-up after being randomly allocated to four prosthetic...... 1, 6, and 7.Bone remodeling after total hip arthroplasty may depend on the composition of bearing materials, but age, height, weight, and stem size are also related to changes in BMD....

  20. The use of RANKL-coated brushite cement to stimulate bone remodelling.

    Science.gov (United States)

    Le Nihouannen, Damien; Hacking, S Adam; Gbureck, Uwe; Komarova, Svetlana V; Barralet, Jake E

    2008-08-01

    Calcium phosphate cements were first proposed as synthetic bone substitutes over two decades ago, however, they are characterised by slow chemical or cellular resorption and a slow osteointegration. In contrast, bone autograft has been shown to stimulate osteoclastogenesis and angiogenesis resulting in active bone remodelling and rapid graft incorporation. Therefore, we aimed to develop a biomaterial able to release a key stimulator of the bone remodelling process, cytokine RANKL. Cylinders of brushite cement, hydroxyapatite cement and sodium alginate were loaded with RANKL either by incorporation into the cement or by coating the material with soluble RANKL. To test the biological activity of these formulations, we assessed their effectiveness in inducing osteoclast formation from RAW 264.7 monocytic cell line. Only brushite and hydroxyapatite cements coated with RANKL allowed for retaining sufficient biological activity to induce osteoclast formation. Most efficient was coating 40 mg cylinder of brushite cement with 800 ng RANKL. We have found that RANKL-coated brushite cement exhibits osteoclastogenic activity for at least 1 month at 37 degrees C. Thus, we developed a formulation of brushite cement with RANKL - a synthetic bone graft that is similar to autografts in its ability to actively induce osteoclastogenesis.

  1. Accuracy of both virtual and printed 3-dimensional models for volumetric measurement of alveolar clefts before grafting with alveolar bone compared with a validated algorithm: a preliminary investigation.

    Science.gov (United States)

    Kasaven, C P; McIntyre, G T; Mossey, P A

    2017-01-01

    Our objective was to assess the accuracy of virtual and printed 3-dimensional models derived from cone-beam computed tomographic (CT) scans to measure the volume of alveolar clefts before bone grafting. Fifteen subjects with unilateral cleft lip and palate had i-CAT cone-beam CT scans recorded at 0.2mm voxel and sectioned transversely into slices 0.2mm thick using i-CAT Vision. Volumes of alveolar clefts were calculated using first a validated algorithm; secondly, commercially-available virtual 3-dimensional model software; and finally 3-dimensional printed models, which were scanned with microCT and analysed using 3-dimensional software. For inter-observer reliability, a two-way mixed model intraclass correlation coefficient (ICC) was used to evaluate the reproducibility of identification of the cranial and caudal limits of the clefts among three observers. We used a Friedman test to assess the significance of differences among the methods, and probabilities of less than 0.05 were accepted as significant. Inter-observer reliability was almost perfect (ICC=0.987). There were no significant differences among the three methods. Virtual and printed 3-dimensional models were as precise as the validated computer algorithm in the calculation of volumes of the alveolar cleft before bone grafting, but virtual 3-dimensional models were the most accurate with the smallest 95% CI and, subject to further investigation, could be a useful adjunct in clinical practice. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  2. Effect of laser phototherapy on human alveolar bone repair: micro tomographic and histomorphometrical analysis

    Science.gov (United States)

    Romão, Marcia M. A.; Marques, Márcia M.; Cortes, Arthur R. G.; Horliana, Anna C. R. T.; Moreira, Maria S.; Lascala, Cesar A.

    2015-06-01

    The immediate dental implant placement in the molars region is critical, because of the high amount of bone loss and the discrepancy between the alveolar crest thickness and the dental implant platform. Laser phototherapy (LPT) improves bone repair thus could accelerate the implant placement. Twenty patients were selected for the study. Ten patients were submitted to LPT with GaAlAs diode laser (808nm) during molar extraction, immediately after, 24h, 48h, 72h, 96h and 7 days. The irradiations were applied in contact and punctual mode (100mW, 0.04cm2, 0.75J/cm2, 30s per point, 3J per point). The control group (n=10) received the same treatment; however with the power of the laser off. Forty days later samples of the tissue formed inside the sockets were obtained for further microtomography (microCTs) and histomorphometry analyses. Data were compared by the Student t test, whereas those from the different microCT parameters were compared by the Pearson correlation test (pbone volume, as well as area was significantly higher (pbone repair. By the Pearson correlation test it was possible to infer that the lased group presented a more homogeneous trabecular configuration, which would allow earlier dental implant placement.

  3. Reconstrucción alveolar de maxilar atrófico con injerto de calota craneal: A propósito de dos casos Alveolar bone reconstruction of atrophic maxilla with calvarial bone graft: Two case reports

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    A. Modelo Pérez

    2009-12-01

    Full Text Available La atrofia alveolar del maxilar superior es un reto difícil de solventar en la práctica clínica para la rehabilitación dental sobre implantes. Existen varios métodos de reconstrucción con dicha finalidad. Aunque la elección del método depende de varios factores, de los más importantes son la cantidad de hueso remanente y los deseos del paciente. Presentamos dos casos en los que hemos efectuado la rehabilitación prostodóncica sobre implantes MG Osseous, no removible en uno y removible en el otro. Previa a la colocación de los implantes se llevó a cabo la reconstrucción alveolar con injerto óseo de calota craneal.The alveolar atrophy of superior maxilla is a difficult challenge to resolve in clinical practice for the dental rehabilitation on implants. There are several methods of reconstruction with this purpose. Although the election of the method depends on several factors, most importantly the amount of bone surplus and the desires patient´s. We presented/displayed two cases in which we have carried out the prosthodontist rehabilitation on implants MG Osseous, nonremovable in one and removable in the other. Previous to the positioning of the implants alveolar reconstruction was carried out with calvarial bone graft.

  4. Changes in the population of perivascular cells in the bone tissue remodeling zones under microgravity

    Science.gov (United States)

    Katkova, Olena; Rodionova, Natalia; Shevel, Ivan

    2016-07-01

    Microgravity and long-term hypokinesia induce reduction both in bone mass and mineral saturation, which can lead to the development of osteoporosis and osteopenia. (Oganov, 2003). Reorganizations and adaptive remodeling processes in the skeleton bones occur in the topographical interconnection with blood capillaries and perivascular cells. Radioautographic studies with 3H- thymidine (Kimmel, Fee, 1980; Rodionova, 1989, 2006) have shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic. Hence the study of populations of perivascular stromal cells in areas of destructive changes is actual. Perivascular cells from metaphysis of the rat femoral bones under conditions of modeling microgravity were studied using electron microscopy and cytochemistry (hindlimb unloading, 28 days duration) and biosatellite «Bion-M1» (duration of flight from April 19 till May 19, 2013 on C57, black mice). It was revealed that both control and test groups populations of the perivascular cells are not homogeneous in remodeling adaptive zones. These populations comprise of adjacent to endothelium poorly differentiated forms and isolated cells with signs of differentiation (specific increased volume of rough endoplasmic reticulum in cytoplasm). Majority of the perivascular cells in the control group (modeling microgravity) reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In poorly differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of experimental animals reaction to the alkaline phosphatase is registered not in all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. Under microgravity some poorly differentiated perivascular

  5. Osteoblast connexin43 modulates skeletal architecture by regulating both arms of bone remodeling.

    Science.gov (United States)

    Watkins, Marcus; Grimston, Susan K; Norris, Jin Yi; Guillotin, Bertrand; Shaw, Angela; Beniash, Elia; Civitelli, Roberto

    2011-04-15

    Connexin43 (Cx43) has an important role in skeletal homeostasis, and Cx43 gene (Gja1) mutations have been linked to oculodentodigital dysplasia (ODDD), a human disorder characterized by prominent skeletal abnormalities. To determine the function of Cx43 at early steps of osteogenesis and its role in the ODDD skeletal phenotype, we have used the Dermo1 promoter to drive Gja1 ablation or induce an ODDD mutation in the chondro-osteogenic linage. Both Gja1 null and ODDD mutant mice develop age-related osteopenia, primarily due to a progressive enlargement of the medullary cavity and cortical thinning. This phenotype is the consequence of a high bone turnover state, with increased endocortical osteoclast-mediated bone resorption and increased periosteal bone apposition. Increased bone resorption is a noncell autonomous defect, caused by exuberant stimulation of osteoclastogenesis by Cx43-deficient bone marrow stromal cells, via decreased Opg production. The latter is part of a broad defect in osteoblast differentiation and function, which also results in abnormal structural and material properties of bone leading to decreased resistance to mechanical load. Thus Cx43 in osteogenic cells is a critical regulator of both arms of the bone remodeling cycle, its absence causing structural changes remindful of aged or disused bone.

  6. The role of muscle loading on bone (Remodeling at the developing enthesis.

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    Alexander M Tatara

    Full Text Available Muscle forces are necessary for the development and maintenance of a mineralized skeleton. Removal of loads leads to malformed bones and impaired musculoskeletal function due to changes in bone (remodeling. In the current study, the development of a mineralized junction at the interface between muscle and bone was examined under normal and impaired loading conditions. Unilateral mouse rotator cuff muscles were paralyzed using botulinum toxin A at birth. Control groups consisted of contralateral shoulders injected with saline and a separate group of normal mice. It was hypothesized that muscle unloading would suppress bone formation and enhance bone resorption at the enthesis, and that the unloading-induced bony defects could be rescued by suppressing osteoclast activity. In order to modulate osteoclast activity, mice were injected with the bisphosphonate alendronate. Bone formation was measured at the tendon enthesis using alizarin and calcein fluorescent labeling of bone surfaces followed by quantitative histomorphometry of histologic sections. Bone volume and architecture was measured using micro computed tomography. Osteoclast surface was determined via quantitative histomorphometry of tartrate resistant acid phosphatase stained histologic sections. Muscle unloading resulted in delayed initiation of endochondral ossification at the enthesis, but did not impair bone formation rate. Unloading led to severe defects in bone volume and trabecular bone architecture. These defects were partially rescued by suppression of osteoclast activity through alendronate treatment, and the effect of alendronate was dose dependent. Similarly, bone formation rate was increased with increasing alendronate dose across loading groups. The bony defects caused by unloading were therefore likely due to maintained high osteoclast activity, which normally decreases from neonatal through mature timepoints. These results have important implications for the treatment of

  7. 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.

  8. Research progress on alveolar bone development%牙槽骨发生的研究进展

    Institute of Scientific and Technical Information of China (English)

    欧明明; 黄晓峰; 韩培彦

    2014-01-01

    Absorption and loss of alveolar bone are some of the main reasons of tooth loss. Therefore, clinics must understand how to reconstruct alveolar bone. To date, treatment strategies to rescue or regenerate the alveolar bone are limited. The process of developing biological alveolar bone formation in the early stage may help to understand the mechanism of bone regeneration and benefit clinical treatment. Alveolar bone is partially derived from dental follicle cells. Many growth factors and transcription factors are involved in the development of alveolar bone. In this review, the relationship between alveolar bone formation and many factors will be discussed in detail. This review also highlights recent advances in understanding alveolar bone development with and without varying factors.%牙槽骨再生是牙周组织疾病治疗的根本。牙槽骨发生属于膜内成骨,成骨细胞来源于多潜能神经嵴牙囊间质细胞,伴随着牙体的发生而发生。牙胚由成釉器、牙乳头和牙囊组成,而牙囊则形成牙骨质、牙周膜和牙槽骨。骨形态发生蛋白(BMP)可启动、促进和调节骨的发生、发育、生长、重塑和修复。核心结合因子1可使牙囊间质细胞向成骨细胞分化,对膜内成骨和软骨内成骨有控制作用。成纤维细胞生长因子通过调控骨干细胞复制,成骨细胞分化和程序性死亡,各种细胞及相关因子的表达来控制骨形成。WNT在BMP的刺激下促进成骨细胞分化,增强BMP诱导下的Ⅰ型胶原、特殊骨基质蛋白和骨钙蛋白表达。声音刺猬蛋白、转化生长因子β和肌节同源盒蛋白2在牙槽骨和牙骨质中表达强烈,其基因突变可致牙槽骨丧失。本文就牙槽骨发生与牙囊间的关系以及参与牙槽骨发生的细胞因子等研究进展作一综述。

  9. A joined role of canopy and reversal cells in bone remodeling--lessons from glucocorticoid-induced osteoporosis.

    Science.gov (United States)

    Jensen, Pia Rosgaard; Andersen, Thomas Levin; Hauge, Ellen-Margrethe; Bollerslev, Jens; Delaissé, Jean-Marie

    2015-04-01

    Successful bone remodeling demands that osteoblasts restitute the bone removed by osteoclasts. In human cancellous bone, a pivotal role in this restitution is played by the canopies covering the bone remodeling surfaces, since disruption of canopies in multiple myeloma, postmenopausal- and glucocorticoid-induced osteoporosis is associated with the absence of progression of the remodeling cycle to bone formation, i.e., uncoupling. An emerging concept explaining this critical role of canopies is that they represent a reservoir of osteoprogenitors to be delivered to reversal surfaces. In postmenopausal osteoporosis, this concept is supported by the coincidence between the absence of canopies and scarcity of cells on reversal surfaces together with abortion of the remodeling cycle. Here we tested whether this concept holds true in glucocorticoid-induced osteoporosis. A histomorphometric analysis of iliac crest biopsies from patients exposed to long-term glucocorticoid treatment revealed a subpopulation of reversal surfaces corresponding to the characteristics of arrest found in postmenopausal osteoporosis. Importantly, these arrested reversal surfaces were devoid of canopy coverage in almost all biopsies, and their prevalence correlated with a deficiency in bone forming surfaces. Taken together with the other recent data, the functional link between canopies, reversal surface activity, and the extent of bone formation surface in postmenopausal- and glucocorticoid-induced osteoporosis, supports a model where bone restitution during remodeling demands recruitment of osteoprogenitors from the canopy onto reversal surfaces. These data suggest that securing the presence of functional local osteoprogenitors deserves attention in the search of strategies to prevent the bone loss that occurs during bone remodeling in pathological situations.

  10. The Regulatory Roles of MicroRNAs in Bone Remodeling and Perspectives as Biomarkers in Osteoporosis.

    Science.gov (United States)

    Sun, Mengge; Zhou, Xiaoya; Chen, Lili; Huang, Shishu; Leung, Victor; Wu, Nan; Pan, Haobo; Zhen, Wanxin; Lu, William; Peng, Songlin

    2016-01-01

    MicroRNAs are involved in many cellular and molecular activities and played important roles in many biological and pathological processes, such as tissue formation, cancer development, diabetes, neurodegenerative diseases, and cardiovascular diseases. Recently, it has been reported that microRNAs can modulate the differentiation and activities of osteoblasts and osteoclasts, the key cells that are involved in bone remodeling process. Meanwhile, the results from our and other research groups showed that the expression profiles of microRNAs in the serum and bone tissues are significantly different in postmenopausal women with or without fractures compared to the control. Therefore, it can be postulated that microRNAs might play important roles in bone remodeling and that they are very likely to be involved in the pathological process of postmenopausal osteoporosis. In this review, we will present the updated research on the regulatory roles of microRNAs in osteoblasts and osteoclasts and the expression profiles of microRNAs in osteoporosis and osteoporotic fracture patients. The perspective of serum microRNAs as novel biomarkers in bone loss disorders such as osteoporosis has also been discussed.

  11. MAGED1 is a negative regulator of bone remodeling in mice.

    Science.gov (United States)

    Liu, Mei; Xu, Lijuan; Ma, Xiao; Xu, Jiake; Wang, Jing; Xian, Mengmeng; Zhou, Xiaotian; Wang, Min; Wang, Fang; Qin, An; Pan, Qiuhui; Wen, Chuanjun

    2015-10-01

    Melanoma antigen family D1 (MAGED1), an important adaptor protein, has been shown to ubiquitously express and play critical roles in many aspects of cellular events and physiological functions. However, its role in bone remodeling remains unknown. We, therefore, analyzed the bone phenotype of Maged1-deficient mice. Maged1-deficient mice displayed a significant osteoporotic phenotype with a marked decrease in bone density and deterioration of trabecular architecture. Histomorphometric analysis demonstrated an increased mineral apposition rate as well as increased osteoclast number and surface in Maged1 knockout mice. At the cellular level, Maged1-deficient osteoblasts exhibited an increased proliferation rate and accelerated differentiation. MAGED1 deficiency also caused a promotion in osteoclastogenesis, and that was attributed to the cell autonomous acceleration of differentiation in osteoclasts and an increased receptor activator of NF-κB ligand/osteoprotegerin ratio, a major index of osteoclastogenesis, in osteoblasts. Thus, we identified MAGED1 as a novel regulator of osteoblastogenesis, osteoclastogenesis, and bone remodeling in a mouse model.

  12. The Regulatory Roles of MicroRNAs in Bone Remodeling and Perspectives as Biomarkers in Osteoporosis

    Directory of Open Access Journals (Sweden)

    Mengge Sun

    2016-01-01

    Full Text Available MicroRNAs are involved in many cellular and molecular activities and played important roles in many biological and pathological processes, such as tissue formation, cancer development, diabetes, neurodegenerative diseases, and cardiovascular diseases. Recently, it has been reported that microRNAs can modulate the differentiation and activities of osteoblasts and osteoclasts, the key cells that are involved in bone remodeling process. Meanwhile, the results from our and other research groups showed that the expression profiles of microRNAs in the serum and bone tissues are significantly different in postmenopausal women with or without fractures compared to the control. Therefore, it can be postulated that microRNAs might play important roles in bone remodeling and that they are very likely to be involved in the pathological process of postmenopausal osteoporosis. In this review, we will present the updated research on the regulatory roles of microRNAs in osteoblasts and osteoclasts and the expression profiles of microRNAs in osteoporosis and osteoporotic fracture patients. The perspective of serum microRNAs as novel biomarkers in bone loss disorders such as osteoporosis has also been discussed.

  13. Histological Comparison in Rats between Carbonate Apatite Fabricated from Gypsum and Sintered Hydroxyapatite on Bone Remodeling

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    Yasunori Ayukawa

    2015-01-01

    Full Text Available Carbonate apatite (CO3Ap, the form of apatite found in bone, has recently attracted attention. The purpose of the present study was to histologically evaluate the tissue/cellular response toward the low-crystalline CO3Ap fabricated using a dissolution-precipitation reaction with set gypsum as a precursor. When set gypsum was immersed in a 100°C 1 mol/L Na3PO4 aqueous solution for 24 h, the set gypsum transformed into CO3Ap. Both CO3Ap and sintered hydroxyapatite (s-HAp, which was used as a control, were implanted into surgically created tibial bone defects of rats for histological evaluation. Two and 4 weeks after the implantation, histological sections were created and observed using light microscopy. The CO3Ap granules revealed both direct apposition of the bone matrix by osteoblasts and osteoclastic resorption. In contrast, the s-HAp granules maintained their contour even after 4 weeks following implantation which implied that there was a lack of replacement into the bone. The s-HAp granules were sometimes encapsulated with fibrous tissue, and macrophage polykaryon was occasionally observed directly apposed to the implanted granules. From the viewpoint of bone remodeling, the CO3Ap granules mimicked the bone matrix, suggesting that CO3Ap may be an appropriate bone substitute.

  14. Early reversal cells in adult human bone remodeling: osteoblastic nature, catabolic functions and interactions with osteoclasts.

    Science.gov (United States)

    Abdelgawad, Mohamed Essameldin; Delaisse, Jean-Marie; Hinge, Maja; Jensen, Pia Rosgaard; Alnaimi, Ragad Walid; Rolighed, Lars; Engelholm, Lars H; Marcussen, Niels; Andersen, Thomas Levin

    2016-06-01

    The mechanism coupling bone resorption and formation is a burning question that remains incompletely answered through the current investigations on osteoclasts and osteoblasts. An attractive hypothesis is that the reversal cells are likely mediators of this coupling. Their nature is a big matter of debate. The present study performed on human cancellous bone is the first one combining in situ hybridization and immunohistochemistry to demonstrate their osteoblastic nature. It shows that the Runx2 and CD56 immunoreactive reversal cells appear to take up TRAcP released by neighboring osteoclasts. Earlier preclinical studies indicate that reversal cells degrade the organic matrix left behind by the osteoclasts and that this degradation is crucial for the initiation of the subsequent bone formation. To our knowledge, this study is the first addressing these catabolic activities in adult human bone through electron microscopy and analysis of molecular markers. Periosteoclastic reversal cells show direct contacts with the osteoclasts and with the demineralized resorption debris. These early reversal cells show (1) ¾-collagen fragments typically generated by extracellular collagenases of the MMP family, (2) MMP-13 (collagenase-3) and (3) the endocytic collagen receptor uPARAP/Endo180. The prevalence of these markers was lower in the later reversal cells, which are located near the osteoid surfaces and morphologically resemble mature bone-forming osteoblasts. In conclusion, this study demonstrates that reversal cells colonizing bone surfaces right after resorption are osteoblast-lineage cells, and extends to adult human bone remodeling their role in rendering eroded surfaces osteogenic.

  15. Quantitative analysis of alveolar bone change following implant placement using intraoral radiographic subtraction

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    Kimura, Hiroyuki; Kanda, Shigenobu [Kyushu Univ., Fukuoka (Japan). Graduate School of Dental Science; Tanaka, Takemasa [Kyushu Univ., Fukuoka (Japan). Dental Hospital

    2002-12-01

    The purpose of this study was to develop a procedure for quantitative analysis using intraoral radiographs of alveolar bone after placement of dental implants and to consider the validity of the method. We evaluated the ten patients (2 males and 8 females, average age: 48.4 years-old), who were treated with dental implant operation in the site of mandibular molar region, since October of 1999 until September of 2000 in Kimura Dental Clinic (Kumamoto, Japan). We evaluated the intraoral radiographs taken pre- and post- operatively and at follow-up examination. To detect alveolar bone change on radiograph, we adopted the digital subtraction method. Although the radiographs were taken under an ordinary technique with cone indicator, we did not apply the standardized technique with fixing material customized for each patient. Therefore, we used geometric correction and density compensation before subtraction. We assessed the basic statistical values (mean, variance, kurtosis and skewness) of the region of interest (ROI) of the subtracted images. Also, we noted PPD (probing pocket depth) and BOP (bleeding on probing) at each site as indicators of clinical findings and all implanted sites were classified according to the PPD or BOP, i.e. PPD increased group ''PPD (+)'' and PPD stable group ''PPD (-)'', likewise BOP positive group ''BOP (+)'' and negative group ''BOP (-)''. We considered the statistical values of ROI in each group and compared these findings. Mean and variance values of PPD (+) were higher than those of PPD (-) and there was a significant difference in mean value (p=0.031). Similarly, mean and variance values of BOP (+) were statistically higher than those of BOP (-) (p=0.041 and p=0.0087, respectively). Concerning kurtosis and skewness, there was no difference between PPD (+) and PPD (-), or between BOP (+) and BOP (-). Using our method, the radiographs taken for follow

  16. β-Glucans (Saccharomyces cereviseae) Reduce Glucose Levels and Attenuate Alveolar Bone Loss in Diabetic Rats with Periodontal Disease.

    Science.gov (United States)

    Silva, Viviam de Oliveira; Lobato, Raquel Vieira; Andrade, Eric Francelino; de Macedo, Cristina Gomes; Napimoga, Juliana Trindade Clemente; Napimoga, Marcelo Henrique; Messora, Michel Reis; Murata, Ramiro Mendonça; Pereira, Luciano José

    2015-01-01

    The objective of this study was to assess the effects of oral ingestion of β-glucans isolated from Saccharomyces cereviseae on the metabolic profile, expression of gingival inflammatory markers and amount of alveolar bone loss in diabetic rats with periodontal disease. Diabetes mellitus was induced in 48 Wistar rats by intraperitoneal injection of streptozotocin (80 mg/kg). After confirming the diabetes diagnosis, the animals were treated with β-glucans (by gavage) for 28 days. On the 14th day of this period, periodontal disease was induced using a ligature protocol. β-glucans reduced the amount of alveolar bone loss in animals with periodontal disease in both the diabetic and non-diabetic groups (p periodontal disease (p periodontal disease (p periodontal effects in diabetic rats with periodontal disease.

  17. β-Glucans (Saccharomyces cereviseae) Reduce Glucose Levels and Attenuate Alveolar Bone Loss in Diabetic Rats with Periodontal Disease

    Science.gov (United States)

    2015-01-01

    The objective of this study was to assess the effects of oral ingestion of β-glucans isolated from Saccharomyces cereviseae on the metabolic profile, expression of gingival inflammatory markers and amount of alveolar bone loss in diabetic rats with periodontal disease. Diabetes mellitus was induced in 48 Wistar rats by intraperitoneal injection of streptozotocin (80 mg/kg). After confirming the diabetes diagnosis, the animals were treated with β-glucans (by gavage) for 28 days. On the 14th day of this period, periodontal disease was induced using a ligature protocol. β-glucans reduced the amount of alveolar bone loss in animals with periodontal disease in both the diabetic and non-diabetic groups (p diabetic animals, both with and without periodontal disease (p diabetes and periodontal disease (p periodontal effects in diabetic rats with periodontal disease. PMID:26291983

  18. 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.

  19. Numerical simulation of load-induced bone structural remodelling using stress-limit criterion.

    Science.gov (United States)

    Marzban, Ali; Nayeb-Hashemi, Hamid; Vaziri, Ashkan

    2015-01-01

    A simple and efficient numerical method for predicting the remodelling of adaptive materials and structures under applied loading was presented and implemented within a finite element framework. The model uses the trajectorial architecture theory of optimisation to predict the remodelling of material microstructure and structural organisation under mechanical loading. We used the proposed model to calculate the density distribution of proximal femur in the frontal plane. The loading considered was the hip joint contact forces and muscular forces at the attachment sites of the muscles to the bone. These forces were estimated from a separate finite element calculation using a heterogeneous three-dimensional model of the proximal femur. The density distributions obtained by this procedure has a qualitative similarity with in vivo observations. Solutions displayed the characteristic high-density channels that are evident in the Dual X-ray Absorptiometry scan. There is also evidence of the intramedullary canal, as well as low-density regions in the femoral neck. Several parametric studies were carried out to highlight the advantages of the proposed method, which includes fast convergence and low-computational cost. The potential applications of the proposed method in predicting bone structural remodelling in cancer are also briefly discussed.

  20. Bone marrow-derived progenitor cells augment venous remodeling in a mouse dorsal skinfold chamber model.

    Directory of Open Access Journals (Sweden)

    Megan E Doyle

    Full Text Available The delivery of bone marrow-derived cells (BMDCs has been widely used to stimulate angiogenesis and arteriogenesis. We identified a progenitor-enriched subpopulation of BMDCs that is able to augment venular remodeling, a generally unexplored area in microvascular research. Two populations of BMDCs, whole bone marrow (WBM and Lin(-/Sca-1(+ progenitor cells, were encapsulated in sodium alginate and delivered to a mouse dorsal skinfold chamber model. Upon observation that encapsulated Sca-1(+ progenitor cells enhance venular remodeling, the cells and tissue were analyzed on structural and molecular levels. Venule walls were thickened and contained more nuclei after Sca-1(+ progenitor cell delivery. In addition, progenitors expressed mRNA transcript levels of chemokine (C-X-C motif ligand 2 (CXCL2 and interferon gamma (IFNγ that are over 5-fold higher compared to WBM. Tissues that received progenitors expressed significantly higher protein levels of vascular endothelial growth factor (VEGF, monocyte chemotactic protein-1 (MCP-1, and platelet derived growth factor-BB (PDGF-BB compared to tissues that received an alginate control construct. Nine days following cell delivery, tissue from progenitor recipients contained 39% more CD45(+ leukocytes, suggesting that these cells may enhance venular remodeling through the modulation of the local immune environment. Results show that different BMDC populations elicit different microvascular responses. In this model, Sca-1(+ progenitor cell-derived CXCL2 and IFNγ may mediate venule enlargement via modulation of the local inflammatory environment.

  1. Differentiation potentials of perivascular cells in the bone tissue remodeling zones under microgravity

    Science.gov (United States)

    Rodionova, Natalia; Katkova, Olena

    Adaptive remodeling processes in the skeleton bones occur in the close topographical interconnection with blood capillaries followed by perivascular cells. Radioautographic studies with 3Н- thymidine (Kimmel D.B., Fee W.S., 1980; Rodionova N.V., 1989, 2006) has shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic ones. Using electron microscopy and cytochemistry we studied perivsacular cells in metaphysis of the rats femoral bones under conditions of modeling microgravity (28 days duration) and in femoral bonеs metaphyses of rats flown on board of the space laboratory (Spacelab - 2) It was revealed that population of the perivascular cells is not homogeneous in adaptive zones of the remodeling in both control and test groups (lowering support loading). This population comprises adjacent to endothelium little differentiated forms and isolated cells with differentiation features (specific volume of rough endoplasmic reticulum in cytoplasm is increased). Majority of the perivascular cells in the control group reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In little differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of animals under microgravitaty reaction to the alkaline phosphatase is registered not for all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. There is also visible trend of individual alkaline phosphatase containing perivascular cells amounts decrease (i.e. osteogenic cells-precursors). Under microgravity some little differentiated perivascular cells reveal destruction signs. Found decrease trend of the alkaline phosphatase containing cells (i.e. osteogenic cells) number in

  2. Platelet-rich plasma, plasma rich in growth factors and simvastatin in the regeneration and repair of alveolar bone.

    Science.gov (United States)

    Rivera, César; Monsalve, Francisco; Salas, Juan; Morán, Andrea; Suazo, Iván

    2013-12-01

    Platelet preparations promote bone regeneration by inducing cell migration, proliferation and differentiation in the area of the injury, which are essential processes for regeneration. In addition, several studies have indicated that simvastatin (SIMV), widely used for the treatment of hypercholesterolemia, stimulates osteogenesis. The objective of this study was to evaluate the effects of treatment with either platelet-rich plasma (PRP) or plasma rich in growth factors (PRGF) in combination with SIMV in the regeneration and repair of alveolar bone. The jaws of Sprague Dawley rats (n=18) were subjected to rotary instrument-induced bone damage (BD). Animals were divided into six groups: BD/H2O (n=3), distilled water without the drug and alveolar bone damage; BD/H2O/PRP (n=3), BD and PRP; BD/H2O/PRGF (n=3), BD and PRGF; BD/SIMV (n=3), BD and water with SIMV; BD/SIMV/PRP (n=3), BD, PRP and SIMV; and BD/SIMV/PRGF (n=3), BD, PRGF and SIMV. Conventional histological analysis (hematoxylin and eosin staining) revealed that the BD/SIMV group showed indicators for mature bone tissue, while the BD/SIMV/PRP and BD/SIMV/PRGF groups showed the coexistence of indicators for mature and immature bone tissue, with no statistical differences between the platelet preparations. Simvastatin did not improve the effect of platelet-rich plasma and plasma rich in growth factors. It was not possible to determine which platelet preparation produced superior effects.

  3. Comparative study of bone repair between alveolar and extra-alveolar bone in pigs subjected to osteotomy at low speed and high speed with liquid refrigeration

    OpenAIRE

    2012-01-01

    Introducción: Teniendo en cuenta que el proceso de reparación ósea en los cerdos se muestra en una mayor proximidad entre las variables histológicas estudiadas en comparación con otros modelos biológicos, el presente estudio tenía como objetivo evaluar el proceso histológico de la reparación ósea de osteotomías realizadas en huesos alveolares y extra-alveolar, utilizando instrumentos rotatorios con refrigeración líquida. Material y método: Dieciocho cerdos Large White con peso comprendido ent...

  4. The Effectiveness of Crataegus orientalis M Bieber. (Hawthorn Extract Administration in Preventing Alveolar Bone Loss in Rats with Experimental Periodontitis.

    Directory of Open Access Journals (Sweden)

    Mükerrem Hatipoğlu

    Full Text Available The purpose of this animal study was to evaluate the effects of hawthorn (Crataeus orientalis M Bieber. extract on serum oxidative status and alveolar bone loss in experimental periodontitis. Twenty-seven Wistar rats were assigned to one of the following groups: non- ligated+placebo (saline (NL, n = 9, ligature only+placebo (saline (LO, n = 9, and ligature and treated with hawthorn extract in saline (H, n = 9 (100 mg/kg orogastrically, once a day for 11 days. Periodontitis was induced by submerging a 4/0 silk ligature in the sulcus of the mandibular right first molars of rats, and the animals were sacrificed after 11 days. Micro-CT examinations were performed for linear and volumetric parameter assessment of alveolar bone. Periodontal tissues were histopathologically examined to assess the differences among the study groups. Levels of serum total antioxidant status (TAS/total oxidant status (TOS, and oxidative stress index (OSI were also analyzed. Alveolar bone loss was significantly reduced by hawthorn administration compared to LO group (p<0.05. The number of inflammatory cells and osteoclasts in the LO group was significantly higher than that of the NL and H groups (p< 0.05. The number of osteoblasts in the LO and H groups was significantly higher than that of the NL group (p<0.05. TOS and OSI levels were significantly reduced in H group compared to LO group (P <0.05 and TAS levels were similar in H and NL group (p< 0.05. Hawthorn extract showed inhibitory effect on periodontal inflammation and alveolar bone loss by regulating TAS, TOS and OSI levels in periodontal disease in rats when administered systemically.

  5. The Effectiveness of Crataegus orientalis M Bieber. (Hawthorn) Extract Administration in Preventing Alveolar Bone Loss in Rats with Experimental Periodontitis.

    Science.gov (United States)

    Hatipoğlu, Mükerrem; Sağlam, Mehmet; Köseoğlu, Serhat; Köksal, Ekrem; Keleş, Ali; Esen, Hacı Hasan

    2015-01-01

    The purpose of this animal study was to evaluate the effects of hawthorn (Crataeus orientalis M Bieber.) extract on serum oxidative status and alveolar bone loss in experimental periodontitis. Twenty-seven Wistar rats were assigned to one of the following groups: non- ligated+placebo (saline) (NL, n = 9), ligature only+placebo (saline) (LO, n = 9), and ligature and treated with hawthorn extract in saline (H, n = 9) (100 mg/kg orogastrically, once a day for 11 days). Periodontitis was induced by submerging a 4/0 silk ligature in the sulcus of the mandibular right first molars of rats, and the animals were sacrificed after 11 days. Micro-CT examinations were performed for linear and volumetric parameter assessment of alveolar bone. Periodontal tissues were histopathologically examined to assess the differences among the study groups. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed. Alveolar bone loss was significantly reduced by hawthorn administration compared to LO group (p<0.05). The number of inflammatory cells and osteoclasts in the LO group was significantly higher than that of the NL and H groups (p< 0.05). The number of osteoblasts in the LO and H groups was significantly higher than that of the NL group (p<0.05). TOS and OSI levels were significantly reduced in H group compared to LO group (P <0.05) and TAS levels were similar in H and NL group (p< 0.05). Hawthorn extract showed inhibitory effect on periodontal inflammation and alveolar bone loss by regulating TAS, TOS and OSI levels in periodontal disease in rats when administered systemically.

  6. Low-dose hydrocortisone (HC) replacement therapy is associated with improved bone remodeling balance in hypopituitary subjects

    LENUS (Irish Health Repository)

    Behan, L A

    2011-06-01

    The effect of commonly used glucocorticoid replacement regimens on bone health in hypopituitary subjects is not well known. We aimed to assess the effect of 3 hydrocortisone (HC) replacement dose regimens on bone turnover in this group.10 hypopituitary men with severe ACTH deficiency were randomised in a crossover design to 3 HC dose regimens, Dose A (20mg mane, 10mg tarde), Dose B (10mg twice daily) and Dose C (10mg mane, 5mg tarde). Following 6 weeks of each regimen participants underwent fasting sampling of bone turnover markers.Data from matched controls were used to produce a Z score for subject bone formation and resorption markers and to calculate the bone remodeling balance (formation Z score-resorption Z score) and turnover index ((formation Z + resorption Z)\\/2). A positive bone remodeling balance with increased turnover is consistent with a favourable bone cycle. Data are expressed as median (range).The Pro Collagen Type 1 Peptide (PINP) bone formation Z-score was significantly increased in Dose C, (1.805 (-0.6-10.24)) compared to Dose A (0.035 (-1.0-8.1)) p<0.05 while there was no difference in the C-terminal crosslinking telopeptide (CTx) resorption Z score. The bone remodeling balance was significantly lower for dose A -0.02 (-1.05-4.12) compared to dose C 1.13 (0.13-6.4) (p<0.05). Although there was a trend to an increased bone turnover index with the lower dose regimen, this was not statistically significant.Low dose HC replacement (10mg mane\\/5 mg tarde) was associated with increased bone formation and improved bone remodeling balance which is associated with a more favourable bone cycle. This may have a long term beneficial effect on bone health.

  7. Subchondral bone microstructural damage by increased remodelling aggravates experimental osteoarthritis preceded by osteoporosis.

    Science.gov (United States)

    Bellido, Miriam; Lugo, Laura; Roman-Blas, Jorge A; Castañeda, Santos; Caeiro, Jose R; Dapia, Sonia; Calvo, Emilio; Largo, Raquel; Herrero-Beaumont, Gabriel

    2010-01-01

    Osteoporosis (OP) increases cartilage damage in a combined rabbit model of OP and osteoarthritis (OA). Accordingly, we assessed whether microstructure impairment at subchondral bone aggravates cartilage damage in this experimental model. OP was induced in 20 female rabbits, by ovariectomy and intramuscular injections of methylprednisolone hemisuccinate for four weeks. Ten healthy animals were used as controls. At week 7, OA was surgically induced in left knees of all rabbits. At 22 weeks, after sacrifice, microstructure parameters were assessed by micro-computed tomography, and osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), alkaline phosphatase (ALP) and metalloproteinase 9 (MMP9) protein expressions were evaluated by Western Blot at subchondral bone. In addition, cartilage damage was estimated using the histopathological Mankin score. Mann-Whitney and Spearman statistical tests were performed as appropriate, using SPSS software v 11.0. Significant difference was established at P fractal dimension and MMP9 expression occurred at subchondral bone of OA, OP and OPOA knees vs. controls (P < 0.05). In addition, the severity of cartilage damage was increased in OPOA knees vs. controls (P < 0.05). Remarkably, good correlations were observed between structural and remodelling parameters at subchondral bone, and furthermore, between subchondral structural parameters and cartilage Mankin score. Microstructure impairment at subchondral bone associated with an increased remodelling aggravated cartilage damage in OA rabbits with previous OP. Our results suggest that an increased subchondral bone resorption may account for the exacerbation of cartilage damage when early OA and OP coexist simultaneously in same individuals.

  8. Diet-induced Obesity Alters Bone Remodeling Leading to Decreased Femoral Trabecular Bone Mass in Mice

    Science.gov (United States)

    Body mass derived from an obesity condition may be detrimental to bone health but the mechanism is unknown. This study was to examine changes in bone structure and serum cytokines related to bone metabolism in obese mice induced by a high-fat diet(HFD). Mice fed the HFD were obese and had higher ser...

  9. The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo [Chosun Univ. College of Dentistry, Gwangju (Korea, Republic of)

    2006-09-15

    To assess the width of the labial alveolar bone of the incisive canal and the width of the incisive canal on spiral computed tomographic images of the anterior portion of the maxilla. Study materials included 38 CT scans taken for preoperative planning of implant placement. Axial cross-sectioned image entirely showing the incisive canal at an orifice to the oral cavity, middle portion, and an orifice to the nasal cavity and the diameter of the incisive canal at the middle portion were determined by two specialist using Digora for Windows 2.1. The statistical analyses were carried out using SPSS 12.0.1. When the maxillary central incisors remained, the mean labial alveolar bone width were 6.81{+-}1.41 mm, 6.46{+-}1.33 mm, and 7.91{+-}1.33 mm. When the maxillary central incisors were missed the mean width were 5.42{+-}2.20 mm, 6.23{+-}2.29 mm, and 7.89{+-}2.13 mm. The labial alveolar bone width at middle portion and an orifice to the nasal cavity were of no statistical significant difference according to presence of the maxillary central incisors (P>0.05). The width between oral cavity and nasal cavity, middle portion and to masal cavity revealed statistically significant difference (P<0.05)

  10. Bone grafting of alveolar socket and ovate seat pontic preparation for natural emergence profile for anterior bridge - A case report

    Directory of Open Access Journals (Sweden)

    Vijay Deshmukh

    2009-01-01

    Full Text Available Alveolar atrophy following tooth extraction remains a challenge for future prosthetic restorations. Immediate implant placement and postextraction alveolar bone grafting are two methods that are used to prevent significant postextraction bone loss. Grafting is one of the most common methods of socket preservation widely used to prevent the collapse of oral tissues following extraction so that an excellent esthetic prosthesis can be provided particularly in the anterior maxillary region. The present report describes the management of a maxillary tooth extraction socket using a socket preservation technique involving placement of an osteoconductive slowly resorbable grafting material & resorbable collagen membrane in the extraction socket also called as Bio-Col socket preservation technique followed by a provisional restoration to preserve the tissues & interdental papilla for the placement of future final ovate pontic anterior bridge to give the illusion of the tooth emerging from the gums. This technique resulted in a successful prevention of alveolar bone loss following tooth extraction & maintainence of tissue contour & density which provided a good tissue base for the fabrication of Ovate pontic giving excellent esthetic results.

  11. [Timing of alveolar bone graft and sequences of canine eruption in cases of cleft lip and palate: a systematic review].

    Science.gov (United States)

    Elhaddaoui, Rajae; Bahije, Loubna; Zaoui, Fatima; Rerhrhaye, Wiam

    2017-06-01

    The alveolar bone graft (ABG) is an important phase in the surgical treatment of cleft lip and palate (CLP). The purpose of alveolar bone grafting is to eliminate oronasal fistulas, restore the continuity of the maxilla and provide optimal periodontal support for spontaneous eruption of permanent canines adjacent to the cleft. The purpose of this systematic review was to determine the ideal timing of the ABG that would achieve these goals. Databases consulted were MEDLINE, Embase et EBSCOhost, using keywords present in the MeSH: [cleft lip and palate] and [alveolar bone graft] and [tooth eruption]. Selection criteria included retrospective studies, prospective studies and meta-analyzes dating from January 2005, with available full text. Among 105 references, 9 articles met our selection criteria. ABG carried out before or just after the eruption of permanent canines adjacent to the cleft, between 8 and 12 years old, has the best success rate of the transplant (71% to 89%) and the lowest risk of canine inclusion (5% to 19%). According to literature data, the optimal timing of ABG that provide best results is located between 8 and 12 years, before or just after the eruption of permanent canines adjacent to the cleft. However, this timing could be modified by the multidisciplinary team according priorities, particularly aesthetic, defined for each child. © EDP Sciences, SFODF, 2017.

  12. Tri-Layered Nanocomposite Hydrogel Scaffold for the Concurrent Regeneration of Cementum, Periodontal Ligament, and Alveolar Bone.

    Science.gov (United States)

    Sowmya, S; Mony, Ullas; Jayachandran, P; Reshma, S; Kumar, R Arun; Arzate, H; Nair, Shantikumar V; Jayakumar, R

    2017-04-01

    A tri-layered scaffolding approach is adopted for the complete and concurrent regeneration of hard tissues-cementum and alveolar bone-and soft tissue-the periodontal ligament (PDL)-at a periodontal defect site. The porous tri-layered nanocomposite hydrogel scaffold is composed of chitin-poly(lactic-co-glycolic acid) (PLGA)/nanobioactive glass ceramic (nBGC)/cementum protein 1 as the cementum layer, chitin-PLGA/fibroblast growth factor 2 as the PDL layer, and chitin-PLGA/nBGC/platelet-rich plasma derived growth factors as the alveolar bone layer. The tri-layered nanocomposite hydrogel scaffold is cytocompatible and favored cementogenic, fibrogenic, and osteogenic differentiation of human dental follicle stem cells. In vivo, tri-layered nanocomposite hydrogel scaffold with/without growth factors is implanted into rabbit maxillary periodontal defects and compared with the controls at 1 and 3 months postoperatively. The tri-layered nanocomposite hydrogel scaffold with growth factors demonstrates complete defect closure and healing with new cancellous-like tissue formation on microcomputed tomography analysis. Histological and immunohistochemical analyses further confirm the formation of new cementum, fibrous PDL, and alveolar bone with well-defined bony trabeculae in comparison to the other three groups. In conclusion, the tri-layered nanocomposite hydrogel scaffold with growth factors can serve as an alternative regenerative approach to achieve simultaneous and complete periodontal regeneration. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Evaluation of alveolar bone grafting in unilateral cleft lip and palate patients using a computer-aided diagnosis system

    Energy Technology Data Exchange (ETDEWEB)

    Sutthiprapaporn, Pipop; Kongsomboon, Supaporn; Limmonthol, Saowaluck; Pisek, Poonsak; Keinprasit, Chutimaporn [Khon Kaen University, Khon Kaen (Thailand); Tanimoto, Keiji; Nakamoto, Takashi [Dept. of Oral and Maxillofacial Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan)

    2012-09-15

    This study aimed to evaluate the trabecular bone changes after alveolar bone grafting in unilateral cleft lip and palate (UCLP) patients using a computer-aided diagnosis (CAD) system. The occlusal radiographs taken from 50 UCLP patients were surveyed retrospectively. The images were categorized as: 50 images in group 0 (before bone grafting), 33 images in group 1 (one month after bone grafting), 24 images in group 2 (2-4 months after bone grafting), 15 images in group 3 (5-7 months after bone grafting), and 21 images in group 4 (8 or more months after bone grafting). Each image was grouped as either 'non-cleft side' or 'cleft side'. The CAD system was used five times for each side to calculate the pixel area based on the mathematical morphology. Significant differences were found using a Wilcoxon signed ranks test or paired samples t test. The pixel area showed a significant difference between the 'non-cleft side' and 'cleft side' in group 0 (404.27{+-}103.72/117.73{+-}92.25; p=0.00), group 1 (434.29{+-}86.70/388.31{+-}109.51; p=0.01), and group 4 (430.98{+-}98.11/366.71{+-}154.59; p=0.02). No significant differences were found in group 2 (423.57{+-}98.12/383.47{+-}135.88; p=0.06) or group 3 (433.02{+-}116.07/384.16{+-}146.55; p=0.19). Based on the design of this study, alveolar bone grafting was similar to normal bone within 2-7 months postoperatively.

  14. Effect of Progressive Locomotor Treadmill Compared to Conventional Training on Bone Mineral Density and Bone Remodeling in Paraplegia

    Directory of Open Access Journals (Sweden)

    Ghasemi Mobarake

    2016-11-01

    Full Text Available Background The decrease in bone mass in paraplegic spinal cord injured persons increases the risk factors for fractures. Objectives The aim of the present study was to evaluate the effects of progressive locomotor treadmill training (LT on muscle mass, bone mineral density, and bone remodeling in paraplegia patients. Methods The subjects investigated in this research included seventeen paraplegic spinal cord injured persons who were divided randomly into two groups: LT group (n = 10 and conventional exercise group (n = 7. The exercise training protocol was performed during 12 weeks, 3 days a week, 60 minutes a session. LT included 15 minutes warm-up on stationary bike plus 45 minutes LT with 50 percent body-weight support and finally 10 minutes cool-down as an adjunct to a conventional physiotherapy program. 10 percent loading weight was added per week for LT. Conventional exercise training incorporated 15 minutes warm-up plus 45 minutes over-ground training such as stretch exercise and resistance training. Results The obtained results showed that there were significant differences in serum alkaline phosphatase levels (P < 0.001, osteocalcin levels (P = 0.003, bone mineral content (BMC of the femoral neck (P < 0.001, bone mineral density (BMD of femoral neck (P < 0.001, bone mineral content (BMC of the lumbar spine (P < 0.001, and bone mineral density (BMD of the lumbar spine (P = 0.000 between LT and conventional exercise regimes. Conclusions LT training, in addition to improvement of motor function and reduction of bone loss, can be prescribed as an effective exercise intervention for the treatment of osteoporosis in incomplete spinal cord injured persons.

  15. Role of Periostin in Adhesion and Migration of Bone Remodeling Cells

    Science.gov (United States)

    Cobo, Teresa; Viloria, Cristina G.; Solares, Laura; Fontanil, Tania; González-Chamorro, Elena; De Carlos, Félix; Cobo, Juan; Cal, Santiago; Obaya, Alvaro J.

    2016-01-01

    Periostin is an extracellular matrix protein highly expressed in collagen-rich tissues subjected to continuous mechanical stress. Functionally, periostin is involved in tissue remodeling and its altered function is associated to numerous pathological processes. In orthodontics, periostin plays key roles in the maintenance of dental tissues and it is mainly expressed in those areas where tension or pressing forces are taking place. In this regard, high expression of periostin is essential to promote migration and proliferation of periodontal ligament fibroblasts. However little is known about the participation of periostin in migration and adhesion processes of bone remodeling cells. In this work we employ the mouse pre-osteoblastic MC3T3-E1 and the macrophage-like RAW 264.7 cell lines to overexpress periostin and perform different cell-based assays to study changes in cell behavior. Our data indicate that periostin overexpression not only increases adhesion capacity of MC3T3-E1 cells to different matrix proteins but also hampers their migratory capacity. Changes on RNA expression profile of MC3T3-E1 cells upon periostin overexpression have been also analyzed, highlighting the alteration of genes implicated in processes such as cell migration, adhesion or bone metabolism but not in bone differentiation. Overall, our work provides new evidence on the impact of periostin in osteoblasts physiology. PMID:26809067

  16. Micro-computed tomography and histomorphometric analysis of human alveolar bone repair induced by laser phototherapy: a pilot study.

    Science.gov (United States)

    Romão, M M A; Marques, M M; Cortes, A R G; Horliana, A C R T; Moreira, M S; Lascala, C A

    2015-12-01

    Immediate dental implant placement in the molar region is critical, because of the high amount of bone loss and the discrepancy between alveolar crest thickness and the implant platform. Laser phototherapy (LPT) improves bone repair. The aim of this study was to evaluate the human alveolar bone repair 40 days after molar extraction in patients submitted to LPT. Twenty patients were selected for this randomized controlled clinical trial; 10 underwent LPT (laser group) with a GaAlAs diode laser (808 nm, 100 mW, 0.04 cm(2), 75 J/cm(2), 30s per point, 3 J per point, at five points). The control group patients (n=10) were not irradiated. Forty days later, the tissue formed inside the sockets was analyzed by micro-computed tomography and histomorphometry. Data from the two groups were compared with Student's t-test and Pearson's correlation test. The relative bone volume was significantly higher in the laser group (Palveolar bone repair after molar extraction, leading to a more homogeneous trabecular configuration represented by thin and close trabeculae.

  17. The influence of Aloe vera and xenograft XCB toward of bone morpho protein 2 BMP2 expression and amount of osteoblast of alveolar bone induced into tooth extraction sockets Cavia cobaya

    OpenAIRE

    Utari Kresnoadi; Retno Pudji Rahayu

    2014-01-01

    Tooth extraction can cause inflammation leading to alveolar ridge resorption. In addition, prominent ridge has crucial role for making denture su-ccessfully. Thus, socket preservation is needed to prevent greater alveolar ridge resorption. An innovative material, a combination of Aloe vera and xe-nograft (XCB), is then considered as a biogenic stimulator that can reduce inflammation, as a result, the growth of alveolar bone is expected to be impro-ved. This research is aimed to prove whether ...

  18. Periodontal regeneration in experimentally-induced alveolar bone dehiscence by an improved porous biphasic calcium phosphate ceramic in beagle dogs.

    Science.gov (United States)

    Shi, Han; Ma, Jia; Zhao, Ning; Chen, Yangxi; Liao, Yunmao

    2008-12-01

    Regeneration of lost periodontium is the focus of periodontal therapy. To achieve the effective regeneration, a number of bone graft substitute materials have been developed. This study aimed to investigate the histological response in alveolar bone dehiscences which were filled with an improved biphasic calcium phosphate (BCP) ceramic with more reasonable pore diameter, pore wall thickness and porosity. Twenty-four alveolar bone dehiscences were made surgically in twelve beagle dogs by reflecting mucoperiosteal flaps on the buccal aspect of bilateral lower second premolars and removing alveolar bone. The left dehiscences were treated with BCP ceramic and the contralaterals were cured with the open flap debridement (OFD) as controls. Three dogs were used at week 4, 12, and 24 respectively. Histological observations were processed through three-dimensional micro-computed tomographic imaging, fluorescence and light microscopy. The histological study indicated that the biphasic ceramic was biocompatible, and regeneration was achieved more effectively through the BCP treatment. There were also arrest of epithelial migration apically and formation of new bone and cementum, as well as proliferation of fibrous connective tissues that became attached to the newly formed cementum at week 24, while there was no significant periodontal regeneration in the OFD group only with epithelial tissue migrating into the dehiscence regions. Clinically speaking, though the surgical location formed a limitation to the application of the improved BCP on the periodontal regeneration, the actual result was positive. It proved that the BCP had biocompatibility and was able to act as a stable scaffold to induce periodontal regeneration effectively.

  19. Evaluation of volume and solitary bone cyst remodeling using conventional radiological examination

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, Maciej; Melzer, Piotr [Karol Marcinkowski University of Medical Sciences, Department of Paediatric Orthopaedics, Poznan (Poland); Ignys-O' Byrne, Anna [J. Strus City Hospital, Department of Radiology, Poznan (Poland); Ignys, Iwona [Karol Marcinkowski University of Medical Sciences, Department of Paediatric Gastroenterology and Metabolic Diseases, Poznan (Poland); Mankowski, Przemyslaw [Karol Marcinkowski University of Medical Sciences, Department of Paediatric Surgery, Traumatology and Urology, Poznan (Poland)

    2010-03-15

    To evaluate cyst remodeling, including complete healing and recurrence, and its relation to the cyst volume in two groups of patients, using curettage and bone grafting or methylprednisolone injection. A retrospective analysis was carried out on data from 132 patients with solitary bone cyst, where 79 (59.9%) had undergone curettage and bone grafting and 53 (40.1%) had been administered methylprednisolone injection, with a mean time to follow up of 12 years. The cyst volume was evaluated from conventional radiographs and the method originally reported by Goebel et al. to evaluate the volume of Ewing's sarcoma. The results were analyzed using the criteria of Neer et al. and Capanna et al. The mean cyst volume was 36.8 cm{sup 3}. Recurrence was noted in 16 (20.2%) patients treated with curettage and in nine (17.0%) treated with methylprednisolone. Cyst volume in patients treated with curettage and bone grafting ranged from 8.3 cm{sup 3} to 100.0 cm{sup 3} and with methylprednisolone from 14.0 cm{sup 3} to 50.6 cm{sup 3}. In neither group was the cyst volume related to recurrence. Volumes from 1.3 cm{sup 3} to 81.9 cm{sup 3} were stated for patients treated with curettage and bone grafting, when complete healing was observed; they were significantly lower than for those of the total group of patients who underwent curettage and bone grafting. 1. An association between solitary cyst volume and recurrence in patients treated with either bone curettage and grafting or methylprednisolone was not found. 2. The frequency of complete healing in patients treated with bone curettage and grafting decreased with an increase in the cyst volume. (orig.)

  20. EFFECT OF LOCATION AND BONE GRAFT REMODELING ON RESULTS OF BRISTOW-LATARJET PROCEDURE

    Directory of Open Access Journals (Sweden)

    D. A. Malanin

    2016-01-01

    Full Text Available Introduction. Operation Bristow-Latarjet proved itself as one of the most effective and predictable surgical treatments. despite its widespread use, there are various complications associated with improper installation of the bone block and the violation of its remodeling.Objective: To obtain new data on the effect of location and remodeling of bone graft block on functional outcome and stability of the shoulder joint in patients with recurrent anterior instability after the operation Bristow-latarjet.Material and methods. The material for the study served as the analysis of results of treatment of 64 patients with posttraumatic recurrent anterior shoulder dislocation who underwent Bristow-latarjet operation. postoperatively, assessed a provision and the degree of bone remodeling unit according to computed tomography in the sagittal, axial slices, and through 3d modeling. To evaluate the functional outcome scale were used western Ontario Shoulder Index (wOSI and Rowe scale.Results. At the level of the articular surface (congruent or flattening in the axial plane were 89% bone blocks, too medially or laterally arranged 9% and 2% grafts, respectively. On sagittal cT images in the middle third of the articular surface of the scapula was located 28% of the bone blocks at the bottom 60%, in the upper third of 12%. Analysis of the dependence of the results of treatment of graft positioning showed that patients with excellent and good summary on the scale WOSI and Rowe, had a correct location of the bone block in the middle and lower third of the articular process of the blade. It can be assumed that excessive lateralized or medialized bone block position in the axial plane of a more profound effect on the outcome than cranial displacement of the latter with the sagittal plane. Bony union of the graft was found by CT in 74% of cases, soft tissue 26%, the degree of resorption of the graft revealed 0-1 84% 2-3 degree in 26% of cases. In the last periods

  1. Implementation and Integration of a Finite Element Model into the Bone Remodeling Model to Characterize Skeletal Loading

    Science.gov (United States)

    Werner, C. R.; Lewandowski, B.; Boppana, A.; Pennline, J. A.

    2017-01-01

    NASA's Digital Astronaut Project is developing a bone physiology model to predict changes in bone mineral density over the course of a space mission. The model intends to predict bone loss due to exposure in microgravity as well as predicting bone maintenance due to mechanical stimulus generated by exercise countermeasures. These predictions will be used to inform exercise device efficacy and to help design exercise protocols that will maintain bone mineral density during long exposures to microgravity during spaceflight. The mechanical stimulus and the stresses that are exhibited on the bone are important factors for bone remodeling. These stresses are dependent on the types of exercise that are performed and vary throughout the bone due to the geometry. A primary area of focus for bone health is the proximal femur. This location is critical in transmitting loads between the upper and lower body and have been known to be a critical failure point in older individuals with conditions like osteoporosis.

  2. Detection of active alveolar bone destruction in human periodontal disease by analysis of radiopharmaceutical uptake after a single injection of 99m-Tc-methylene diphosphonate

    Energy Technology Data Exchange (ETDEWEB)

    Jeffcoat, M.K.; Williams, R.C.; Holman, B.L.; English, R.; Goldhaber, P.

    1986-01-01

    Previous studies have shown that, following a single injection of 99m-Tc-MDP, measurement of bone-seeking radiopharmaceutical uptake can detect ''active'' alveolar bone loss due to periodontal disease in beagle dogs, as determined by radiographs taken at the time of, and several months after, the nuclear medicine procedure. The efficacy of this diagnostic test, however, had not been assessed in human periodontal disease. The ability of a single boneseeking radiopharmaceutical uptake examination to detect ''active'' alveolar bone loss due to periodontal disease in human patients was assessed by comparing a single uptake measurement to the rate of bone loss determined from serial radiographs taken over a 6-month period. Uptake was expressed as a ratio of the cpm from the alveolar bone divided by the cpm from the non-tooth supporting bone of the nuchal crest. High uptake ratios were associated with ''active'' loss and low uptake ratios were associated with little if any change in alveolar bone height (p<0.001). The nuclear medicine examination was an accurate detector of periodontal disease activity in nearly 80% of the individual teeth studied. These data indicate that high bone-seeking radiopharmaceutical uptake ratios may be pathognomonic of active bone loss in human periodontal disease.

  3. Diabetes mellitus related bone metabolism and periodontal disease.

    Science.gov (United States)

    Wu, Ying-Ying; Xiao, E; Graves, Dana T

    2015-06-26

    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.

  4. Diabetes mellitus related bone metabolism and periodontal disease

    Science.gov (United States)

    Wu, Ying-Ying; Xiao, E; Graves, Dana T

    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. PMID:25857702

  5. 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.

  6. 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.

  7. Bone remodelling in the proximal femur after Charnley total hip arthroplasty.

    Science.gov (United States)

    Cohen, B; Rushton, N

    1995-09-01

    We measured bone mineral density (BMD) in the proximal femur by dual-energy X-ray absorptiometry (DEXA) in 20 patients after cemented total hip arthroplasty over a period of one year. We found a statistically significant reduction in periprosthetic BMD after six months on the medial side and on the lateral side adjacent to the mid and distal thirds of the prosthesis. At one year after operation there was a mean 6.7% reduction in BMD in the region of the calcar and a mean 5.3% increase in BMD in the femoral shaft distal to the tip of the implant. These changes reflect a pattern of reduced stress in the proximal femur and increased stress around the tip of the prosthesis. They support current concepts of bone remodelling in the proximal femur in response to prosthetic implantation.

  8. Long-term prediction of three-dimensional bone architecture in simulations of pre-, peri- and post-menopausal microstructural bone remodeling.

    Science.gov (United States)

    Müller, Ralph

    2005-03-01

    The mechanical behavior of trabecular bone depends on the internal bone structure. It is generally accepted now that the trabecular bone structure is a result of a load adaptive bone remodeling. The mathematical laws that relate bone remodeling to the local state of stress and strain, however, are still under investigation. The aim of this project was to investigate if changes in the trabecular architecture as observed with age-related bone loss and osteoporosis can be predicted from a computer model that simulates bone resorption after hormone depletion based on realistic models of trabecular microstructure using micro-computed tomography (muCT). A compact desktop muCT providing a nominal isotropic resolution of 14 mum was used to measure two groups of seven trabecular bone specimens from pre-menopausal and post-menopausal women respectively. A novel algorithm was developed to simulate age-related bone loss for the specimens in the first group. The algorithm, also referred to as simulated bone atrophy (SIBA), describes a truly three-dimensional approach and is based directly on cellular bone remodeling with an underlying realistic time frame. Bone resorption is controlled by osteoclastic penetration depth and bone formation is governed by the efficiency level of the osteoblasts. The simulation itself describes an iterative process with a cellular remodeling cycle of 197 days. Activation frequency is controllable and can be adjusted for the different phases of pre-, peri- and post-menopause. For our simulations, osteoblastic and osteoclastic activities were in balance until the onset of menopause, set to be at the age of 50 years. In that period, the structure remained almost constant. After the onset of menopause an imbalance in the cell activities was modeled resulting in a net bone loss. The doubling of the activation frequency in the peri-menopausal phase caused a pronounced loss. Using advanced animation tools and quantitative bone morphometry, the changes in

  9. Neutrophil mobilization by surface-glycan altered Th17-skewing bacteria mitigates periodontal pathogen persistence and associated alveolar bone loss.

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    Rajendra P Settem

    Full Text Available Alveolar bone (tooth-supporting bone erosion is a hallmark of periodontitis, an inflammatory disease that often leads to tooth loss. Periodontitis is caused by a select group of pathogens that form biofilms in subgingival crevices between the gums and teeth. It is well-recognized that the periodontal pathogen Porphyromonas gingivalis in these biofilms is responsible for modeling a microbial dysbiotic state, which then initiates an inflammatory response destructive to the periodontal tissues and bone. Eradication of this pathogen is thus critical for the treatment of periodontitis. Previous studies have shown that oral inoculation in mice with an attenuated strain of the periodontal pathogen Tannerella forsythia altered in O-glycan surface composition induces a Th17-linked mobilization of neutrophils to the gingival tissues. In this study, we sought to determine if immune priming with such a Th17-biasing strain would elicit a productive neutrophil response against P. gingivalis. Our data show that inoculation with a Th17-biasing T. forsythia strain is effective in blocking P. gingivalis-persistence and associated alveolar bone loss in mice. This work demonstrates the potential of O-glycan modified Tannerella strains or their O-glycan components for harnessing Th17-mediated immunity against periodontal and other mucosal pathogens.

  10. Nicotine effect on bone remodeling during orthodontic tooth movement: Histological study in rats

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    Ricardo Lima Shintcovsk

    2014-04-01

    Full Text Available Introduction: Nicotine is harmful to angiogenesis, osteogenesis and synthesis of collagen. Objective: The aim of this study was to investigate the effect of nicotine on bone remodeling during orthodontic movement in rats. Methods: Eighty male Wistar rats were randomly divided into three groups: Group C (control, group CM (with orthodontic movement and group NM (nicotine with orthodontic movement groups. The animals comprising groups C and CM received 0.9% saline solution while group NM received nicotine solution (2 mg/kg. A nickel-titanium closed-coil spring was used to induce tooth movement. The animals were euthanized and tissue specimens were processed histologically. We quantified blood vessels, Howship's lacunae and osteoclast-like cells present in the tension and compression areas of periodontal ligaments. The extent of bone formation was evaluated under polarized light to determine the percentage of immature/mature collagen. Results: We observed lower blood vessel densities in the NM group in comparison to the CM group, three (p < 0.001 and seven (p < 0.05 days after force application. Osteoclast-like cells and Howship's lacunae in the NM group presented lower levels of expression in comparison to the CM group, with significant differences on day 7 (p < 0.05 for both variables and day 14 (p < 0.05 for osteoclast-like cells and p < 0.01 for Howship's lacunae. The percentage of immature collagen increased in the NM group in comparison to the CM group with a statistically significant difference on day 3 (p < 0.05, day 7 (p < 0.001, day 14 (p < 0.001 and day 21 (p < 0.001. Conclusions: Nicotine affects bone remodeling during orthodontic movement, reducing angiogenesis, osteoclast-like cells and Howship's lacunae, thereby delaying the collagen maturation process in developed bone matrix.

  11. Changes in the fractal dimension, feret diameter, and lacunarity of mandibular alveolar bone during initial healing of dental implants.

    Science.gov (United States)

    Önem, Erinç; Baksı, B Güniz; Sogur, Elif

    2012-01-01

    To evaluate the combination of fractal dimension (FD), lacunarity, and Feret diameter (FeD) to quantitatively characterize structural changes of mandibular alveolar bone around dental implants during initial healing. Three standard-sized regions of interest (ROIs) (mesial and distal crest and apical area) around implants and three ROIs of the same size in the alveolar bone on the contralateral side were analyzed on digital panoramic images. FD was calculated using the box-counting method, and lacunarity was calculated using the FracLac plugin of Image J software. FeD was measured in the same ROIs. Comparisons of the groups were done with the Dunnett test. Forty-two implants in the posterior mandibles of 21 patients were used for FD measurements. A total of 189 ROIs was segmented into binary images. Mean FD values for mesial, distal, and apical ROIs around implants were 1.26, 1.36, and 1.4, respectively. The mean FD of alveolar bone around premolars/molars was 1.39 for all ROIs. The mean FeD for mesial, distal, and apical ROIs around implants was 7.63, 7.86, and 8.02, respectively, whereas it ranged between 7.88 and 8.13 for premolar teeth. Mean lacunarity values for mesial, distal, and apical ROIs around implants were 0.53, 0.51, and 0.48, respectively. Lacunarity values for ROIs around premolars ranged between 0.45 and 0.50. No significant differences were observed in FD, FeD, or lacunarity measurements between ROIs around implants and around teeth. The satisfactory healing of bone following implant placement may be monitored by calculating FD, lacunarity, and FeD using digital panoramic images. Although preliminary, these values may alert the practitioner to any implants with loss of stability.

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

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    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.

  13. Effects of constitutive β-catenin activation on vertebral bone growth and remodeling at different postnatal stages in mice.

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    Min Jia

    Full Text Available BACKGROUND AND OBJECTIVE: The Wnt/β-catenin signaling pathway is essential for controlling bone mass; however, little is known about the variable effects of the constitutive activation of β-catenin (CA-β-catenin on bone growth and remodeling at different postnatal stages. The goal of the present study was to observe the effects of CA-β-catenin on vertebral bone growth and remodeling in mice at different postnatal stages. In particular, special attention was paid to whether CA-β-catenin has detrimental effects on these processes. METHODS: Catnblox(ex 3 mice were crossed with mice expressing the TM-inducible Cre fusion protein, which could be activated at designated time points via injection of tamoxifen. β-catenin was stabilized by tamoxifen injection 3 days, and 2, 4, 5, and 7 months after birth, and the effects lasted for one month. Radiographic imaging, micro-computed tomography, immunohistochemistry, and safranin O and tartrate-resistant acid phosphatase staining were employed to observe the effects of CA-β-catenin on vertebral bone growth and remodeling. RESULTS: CA-β-catenin in both early (3 days after birth and late stages (2, 4, 5, and 7 months after birth increased bone formation and decreased bone resorption, which together increased vertebral bone volume. However, when β-catenin was stabilized in the early stage, vertebral linear growth was retarded, and the mice demonstrated shorter statures. In addition, the newly formed bone was mainly immature and located close to the growth plate. In contrast, when β-catenin was stabilized in the late stage, vertebral linear growth was unaffected, and the newly formed bone was mainly mature and evenly distributed throughout the vertebral body. CONCLUSIONS: CA-β-catenin in both early and late stages of growth can increase vertebral bone volume, but β-catenin has differential effects on vertebral growth and remodeling when activated at different postnatal stages.

  14. The Influence of Therapeutic Radiation on the Patterns of Bone Remodeling in Ovary-Intact and Ovariectomized Mice

    Science.gov (United States)

    Hui, Susanta K; Fairchild, Gregory R; Kidder, Louis S; Sharma, Manju; Bhattacharya, Maryka; Jackson, Scott; Le, Chap; Petryk, Anna; Islam, Mohammad Saiful; Yee, Douglas

    2013-01-01

    Purpose To characterize changes in bone remodeling associated with localized radiation that models therapeutic cancer treatment in ovary-intact and ovariectomized mice and evaluate the influence of radiation on the pattern of bone mineral remodeling. Methods Young adult, female BALB/c mice, ovary-intact (I) and ovariectomized (OVX), were used (n=71). All mice were intravenously injection with 15 μCi 45Ca. Thirty days post-45Ca administration, the hind limbs of 17 mice were exposed to a single 16 Gy radiation (R). The time course of 45Ca excretion, serum CTx and osteocalcin markers, and cancellous bone volume fraction (BV/TV) and cortical thickness (Ct.Th) of the distal femur were measured. Cellular activity and dynamic histomorphometry were performed. Results Irradiation resulted in rapid increases in fecal 45Ca excretion compared to control groups, indicating increased bone remodeling. CTX increased rapidly after irradiation, followed by an increase in osteocalcin concentration. BV/TV decreased in the ovary-intact mice following irradiation. Ct.Th increased in the OVX groups following irradiation. I+R exhibited diminished osteoblasts surface, osteoclast number and mineral apposition rate. Conclusions Our murine model showed the systemic effects (via 45Ca excretion) and local effects (via bone microarchitecture and surface activity) of clinically-relevant, therapeutic radiation exposure. Ovary-intact and ovariectomized murine models have similar 45Ca excretion but different bone microarchitecture responses. 45Ca assay effectively indicates the onset and rate of systemic bone mineral remodeling, providing real time assessment of changes in bone histomorphometric parameters. Monitoring bone health via a bone mineral marker may help identify the appropriate time for clinical intervention to preserve skeletal integrity. PMID:23314741

  15. 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.

  16. Effect of nasal salmon calcitonin on bone remodeling and bone mass in postmenopausal osteoporosis.

    Science.gov (United States)

    Thamsborg, G; Jensen, J E; Kollerup, G; Hauge, E M; Melsen, F; Sorensen, O H

    1996-02-01

    The effect of nasal salmon calcitonin (SCT) on bone has been investigated by densitometry, biochemical markers of bone turnover, and histomorphometry. 62 women (mean age 65 years) who had experienced Colles' fracture after menopause were randomized to receive either nasal salmon calcitonin (SCT) 200 IU or nasal placebo daily for 24 months. All received a daily supplement of 0.5 g calcium. There was a significant increase above baseline in the bone mineral density of the lumbar spine in the SCT group (2.5%; 95% confidence interval 0.9--4.2%) and in the placebo group (1.7%; 95% confidence interval 0.3--3.1%) after 24 months, but the difference between the groups was not significant (0.8%; 95% confidence interval -1.2-3.0%). Serum levels of osteocalcin decreased significantly below baseline in the SCT group, whereas they were unchanged in the placebo group. At months 12 and 24, serum levels of osteocalcin were significantly lower in the SCT group than in the placebo group (p transient decrease was observed in the placebo group. The differences between the groups were, however, not significant. The erosion depth was significantly lower in the SCT group than in the placebo group after 12 months (median [interquartile range]; 46.9 mu m [10.4] vs. 50.5 mu m [10.7]; p = 0.03), whereas bone volume and activation frequency did not differ between the groups. This study indicates that nasal SCT in a dose of 200 IU daily induces only a minor inhibition of bone resorption and therefore produces only a minor increase in bone mass. Furthermore, it seems that nasal SCT in a dose of 200 IU does not interfere with the recruitment of new bone multicellular units, but preferably decreases ongoing osteoclastic bone resorption.

  17. Bilocular Stafne Bone Defect above And Below the Inferior Alveolar Canal Assessed by Cone Beam Computed Tomography: A Case Report

    Directory of Open Access Journals (Sweden)

    Mahrokh Imanimoghaddam

    2015-09-01

    Full Text Available Stafne bone defect is a bone depression containing salivary gland or fatty soft tissue on the lingual surface of the mandible. The most common location is within the submandibular gland fossa and often close to the inferior border of the mandible. This defect is asymptomatic and generally discovered only incidentally during radiographic examination of the area. Stafne bone defect appears as a well-defined, corticated, unilocular radiolucency below the mandibular canal. Although it is not uncommon for this defect to appear as a round or ovoid radiolucency, it is rarely seen as a multilocular radiolucency. This report presents a case of a developmental salivary gland defect with multilocular radiolucency above the inferior alveolar canal in a male patient

  18. Electropolished Titanium Implants with a Mirror-Like Surface Support Osseointegration and Bone Remodelling

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    Cecilia Larsson Wexell

    2016-01-01

    Full Text Available This work characterises the ultrastructural composition of the interfacial tissue adjacent to electropolished, commercially pure titanium implants with and without subsequent anodisation, and it investigates whether a smooth electropolished surface can support bone formation in a manner similar to surfaces with a considerably thicker surface oxide layer. Screw-shaped implants were electropolished to remove all topographical remnants of the machining process, resulting in a thin spontaneously formed surface oxide layer and a smooth surface. Half of the implants were subsequently anodically oxidised to develop a thickened surface oxide layer and increased surface roughness. Despite substantial differences in the surface physicochemical properties, the microarchitecture and the composition of the newly formed bone were similar for both implant surfaces after 12 weeks of healing in rabbit tibia. A close spatial relationship was observed between osteocyte canaliculi and both implant surfaces. On the ultrastructural level, the merely electropolished surface showed the various stages of bone formation, for example, matrix deposition and mineralisation, entrapment of osteoblasts within the mineralised matrix, and their morphological transformation into osteocytes. The results demonstrate that titanium implants with a mirror-like surface and a thin, spontaneously formed oxide layer are able to support bone formation and remodelling.

  19. Functions and mechanisms of green tea catechins in regulating bone remodeling.

    Science.gov (United States)

    Shen, Chwan-Li; Kwun, In-Sook; Wang, Shu; Mo, Huanbiao; Chen, Lixia; Jenkins, Marjorie; Brackee, Gordon; Chen, Chung-Hwan; Chyu, Ming-Chien

    2013-12-01

    Osteoporosis is caused by an imbalance in bone remodeling, a process involving bone-building osteoblasts and bone-resorptive osteoclasts. Excessive reactive oxygen species and inflammatory responses have been shown to stimulate differentiation and function of osteoclasts while inducing osteoblast apoptosis and suppressing osteoblastic proliferation and differentiation via extracellular signal-regulated kinases (ERK), ERK-dependent nuclear factor-κB and Wnt/β-catenin signaling pathways. The anti-oxidant and anti-inflammatory green tea catechins (GTC) have been shown to promote osteoblastogenesis, suppress osteoclastogenesis and stimulate the differentiation of mesenchymal stem cells into osteoblasts rather than adipocytes by modulating the signaling pathways. This paper reviews the pharmacokinetics and metabolism of GTC, their bone-protective activities evidenced in in vitro and in vivo studies, and the limited clinical studies supporting these preclinical findings. In light of the physical, economical, and social burdens due to osteoporosis, easily accessible and affordable preventive measures such as GTC deserves further clinical studies prior to its clinical application.

  20. Effect of labiolingual inclination of a maxillary central incisor and surrounding alveolar bone loss on periodontal stress: A finite element analysis

    Science.gov (United States)

    Choi, Sung-Hwan; Kim, Young-Hoon; Lee, Kee-Joon

    2016-01-01

    Objective The aim of this study was to investigate whether labial tooth inclination and alveolar bone loss affect the moment per unit of force (Mt/F) in controlled tipping and consequent stresses on the periodontal ligament (PDL). Methods Three-dimensional models (n = 20) of maxillary central incisors were created with different labial inclinations (5°, 10°, 15°, and 20°) and different amounts of alveolar bone loss (0, 2, 4, and 6 mm). The Mt/F necessary for controlled tipping (Mt/Fcont) and the principal stresses on the PDL were calculated for each model separately in a finite element analysis. Results As labial inclination increased, Mt/Fcont and the length of the moment arm decreased. In contrast, increased alveolar bone loss caused increases in Mt/Fcont and the length of the moment arm. When Mt/F was near Mt/Fcont, increases in Mt/F caused compressive stresses to move from a predominantly labial apical region to a palatal apical position, and tensile stresses in the labial area moved from a cervical position to a mid-root position. Although controlled tipping was applied to the incisors, increases in alveolar bone loss and labial tooth inclination caused increases in maximum compressive and tensile stresses at the root apices. Conclusions Increases in alveolar bone loss and labial tooth inclination caused increases in stresses that might cause root resorption at the root apex, despite the application of controlled tipping to the incisors. PMID:27226961

  1. 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.

  2. A histomorphometric study of the effect of doxycycline and erythromycin on bone formation in dental alveolar socket of rat

    Directory of Open Access Journals (Sweden)

    Mohammad Shahabooei

    2015-01-01

    Full Text Available Background: The aim of the present study was to evaluate whether subantimicrobial doses of doxycycline (DOX and erythromycin (EM used for the treatment of peri-implant osteolysis due to their anti-osteoclastogenesis can interfere with the osseous wound healing process in rat alveolar socket. Materials and Methods: Forty-five male Wistar rats had their first maxillary right molar extracted and were divided into three groups. DOX and EM at the doses of 5 mg/kg/day orally (p.o. and 2 mg/kg/day intraperitoneally (i.p. were administered respectively to two separate groups for 7 days after operation. In the control group the animals received normal saline (5 ml/kg. Five rats were sacrificed at 7, 14 and 21 days post-extraction in each study group. A histomorphometric analysis was used to evaluate new bone formation inside the alveolar socket. Significant level was set at 0.05. Results: The findings showed that the percentage of new bone formation (NBF enhanced significantly on days 7 and 14. There was no significant difference in the NBF between DOX and EM groups. Conclusion: Short-term treatment with both DOX and EM enhanced new bone formation without any advances in favor of each drug.

  3. Effect of induced diabetes mellitus on alveolar bone loss after 30 days of ligature-induced periodontal disease.

    Science.gov (United States)

    Gomes, Débora Aline Silva; Spolidorio, Denise Madalena Palomari; Pepato, Maria Teresa; Zuza, Elizangela Partata; de Toledo, Benedicto Egbert Corrêa; Gonçalves, Andréa; Spolidorio, Luis Carlos; Pires, Juliana Rico

    2009-04-01

    Several studies have shown that diabetics are more susceptible to the development of severe periodontal disease. Currently, the use of animal models can be considered a feasible alternative in radiographic assessments of these two pathologies. The purpose of this radiographic study was to evaluate the effect of induced diabetes mellitus on alveolar bone loss after 30 days of ligature-induced periodontal disease. Sixty-four Wistar rats were randomly distributed into four experimental groups. Diabetes was induced in Groups II and IV, while periodontal disease was induced in Groups III and IV; Group I was used as control. In order to perform the radiographic assessment of the specimens, the rats were killed on the 3rd and 30th days of the study. Radiographic measurements were assessed with ANOVA and Tukey's test to determine statistically significant differences (p diabetic group with periodontal disease (Group IV) featured statistically significant greater bone loss when compared to the other groups. These results suggested that the alveolar bone loss resulting from the periodontal disease installation is greater when associated to the diabetes mellitus.

  4. A comparative mechanical and bone remodelling study of all-ceramic posterior inlay and onlay fixed partial dentures.

    Science.gov (United States)

    Field, Clarice; Li, Qing; Li, Wei; Thompson, Mark; Swain, Michael

    2012-01-01

    Comparative studies of bone remodelling and mechanical stresses between inlay and onlay fixed partial dentures (FPD) are rather limited. The purpose of this paper was to evaluate the biological consequence in posterior mandibular bone and the mechanical responses in these two different prosthetic configurations. Three-dimensional (3D) finite element analysis (FEA) models are created to explore the mechanical responses for the inlay and onlay preparations within the same oral environment. Strain induced bone remodelling was simulated under mastication. The remodelling adopted herein relates the strain in the bone to the change of Hounsfield Unit (HU) value in proportion to the surface area density (SAD) of bony morphology, which allows directly correlating to clinical computerised tomography (CT) data. The results show that both FPD designs exhibit a similar resultant change in bone mineral density (BMD) though the onlay configuration leads to a more uniform distribution of bone density. The inlay design results in higher mechanical stresses whilst allowing preservation of healthy tooth structure. This study provides an effective means to further clinical assessment and investigation into biomechanical responses and long-term restorative outcome with different FPD designs. Quantifying in vivo stress distributions associated with inlay/onlay FPDs can further supplement clinical investigations into prosthetic durability, FPD preparation techniques (i.e., taper angles, material development), consequent stress distributions and the ongoing biomechanical responses of mandibular bone. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Periodontal disease-associated compensatory expression of osteoprotegerin is lost in type 1 diabetes mellitus and correlates with alveolar bone destruction by regulating osteoclastogenesis.

    Science.gov (United States)

    Silva, Juliete Aparecida F; Lopes Ferrucci, Danilo; Peroni, Luis Antônio; de Paula Ishi, Eduardo; Rossa-Junior, Carlos; Carvalho, Hernandes F; Stach-Machado, Dagmar Ruth

    2012-01-01

    Alveolar bone resorption results from the inflammatory response to periodontal pathogens. Systemic diseases that affect the host response, such as type 1 diabetes mellitus (DM1), can potentiate the severity of periodontal disease (PD) and accelerate bone resorption. However, the biological mechanisms by which DM1 modulates PD are not fully understood. The aim of this study was to determine the influence of DM1 on alveolar bone resorption and to evaluate the role of receptor activator of nuclear factor-kappaB ligand (RANKL)/osteoprotegerin (OPG) in osteoclastogenesis in rats. PD was induced by means of ligature in nondiabetic and in streptozotocyn-induced DM1 rats. Morphological and morphometric analyses, stereology and osteoclast counting were performed. RANKL and OPG mRNA levels, protein content, and location were determined. PD caused alveolar bone resorption, increased the number of osteoclasts in the alveolar bone crest and also promoted changes in RANKL/OPG mRNA expression. DM1 alone showed alveolar bone destruction and an increased number of osteoclasts at the periapical and furcal regions. DM1 exacerbated these characteristics, with a greater impact on bone structure, resulting in a low OPG content and a higher RANKL/OPG ratio, which correlated with prominent osteoclastogenesis. This work demonstrates that the effects of PD and DM1 enhance bone destruction, confirms the importance of the RANKL signaling pathway in bone destruction in DM1 in animal models and suggests the existence of alternative mechanisms potentiating bone degradation in PD. Copyright © 2012 S. Karger AG, Basel.

  6. Effect of 15% Alcohol Dependence on Alveolar Bone Loss and TNF-α Secretion in Wistar Rats.

    Science.gov (United States)

    Wagner, Marcius Comparsi; Rocha, José Mariano da; Gaio, Eduardo José; Cavagni, Juliano; Carrard, Vinícius Coelho; Rösing, Cassiano Kuchenbecker

    2016-01-01

    The aim of the present study was to evaluate the effect of 15% alcohol dependence on ligature-induced alveolar bone loss and TNF-α secretion in Wistar rats. Thirty-three male Wistar rats aged 45-60 days (mean weight=253 g) were randomly allocated test or control groups. Test group (n=18) received 15% alcohol as liquid intake and control group (n=15) received water during the experimental period. TNF-α was analyzed by ELISA assay in 11 animals per group. After 14 days of alcohol/water intake, alcohol dependency was assessed and silk ligatures were placed around the left second upper molars. Ligature presence and body weight were checked weekly. After 40 days, animals were sacrificed and the maxillae were defleshed for morphometric analysis using standardized images. All animals in the test group displayed signs of alcohol dependency at day 14. No statistically significant differences in final body weight (334.83±21.38 vs. 322.48±30.65 g, p=0.20) were observed between groups. In relation to alveolar bone loss, no statistically significant difference was observed among test and control groups both for ligated teeth (0.76±0.06 vs. 0.74±0.10 mm, p=0.60) and unligated teeth (0.41±0.16 vs. 0.35±0.05 mm, p=0.22). The TNF-α secretion also did not display statistically significant differences between test and control groups (10.78±1.84 vs. 12.13±2.11 pg/mL, p=0.12). It may be concluded that 15% alcohol dependency was not capable to alter alveolar bone loss and TNF-α secretion in Wistar rats.

  7. 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.

  8. Histomorphometric evaluation of the effect of systemic and topical ozone on alveolar bone healing following tooth extraction in rats.

    Science.gov (United States)

    Erdemci, F; Gunaydin, Y; Sencimen, M; Bassorgun, I; Ozler, M; Oter, S; Gulses, A; Gunal, A; Sezgin, S; Bayar, G R; Dogan, N; Gider, I K

    2014-06-01

    The aim of this study was to investigate the effects of systemic and topical ozone applications on alveolar bone healing following tooth extraction. One hundred and twelve male Wistar rats were divided into eight groups of 14 rats each; seven groups were experimental (A-G) and one formed the control group (K). The experimental groups were further divided into two sub-groups, with seven rats in each - sacrificed on days 14 and 28 (subgroups 1 and 2). The maxillary right central incisors were extracted under general anaesthesia following the administration of local anaesthesia. After sacrifice, semi-serial histological sections were prepared, and mineralized and trabecular bone and osteoid and osteoblast surfaces were measured. Measurements of the trabecular bone showed statistically higher values in the groups treated with systemic ozone (D(2): 50.01 ± 2.12; E(2): 49.03 ± 3.03; F(2): 48.76 ± 2.61; G(2): 50.24 ± 3.37) than in the groups that underwent topical ozone administration (A(2): 46.01 ± 3.07; B(2): 46.79 ± 3.09; C(2): 47.07 ± 2.12; P = 0.030 (G(2)-A(2), G(2)-B(2), G(2)-C(2))). Within the limitations of the current study, it may be concluded that postoperative long-term systemic ozone application can accelerate alveolar bone healing following extraction. However, additional studies are required to clarify the effects of the different ozone applications on new bone formation.

  9. Blood flow for bone remodelling correlates with locomotion in living and extinct birds.

    Science.gov (United States)

    Allan, Georgina H; Cassey, Phillip; Snelling, Edward P; Maloney, Shane K; Seymour, Roger S

    2014-08-15

    Nutrient arteries enter limb bones through discrete foramina on the shafts. They are required for bone remodelling in response to mechanical loading and dynamic forces imposed by locomotion. The cross-sectional area of the nutrient foramen of the femur represents an index of blood flow rate to the shaft and thus provides insight into the animal's level of activity. Morphometric data on femoral length, mass and foramen size from 100 extant bird species and eight extinct moa species were analysed allometrically and phylogenetically. The nutrient foramen blood flow index (Qi) and femur mass (Mf) increase with body mass (Mb). At 1 kg body mass, cursorial species have approximately 2.1 times higher Qi and 1.9 times heavier Mf than volant species. The scaling of Qi on Mf is independent of the primary mode of locomotion, but the ratio Qi/Mf decreases significantly in larger birds, although absolute Qi increases. The overall avian equation for Qi on Mb is not significantly different from previous data from mammals, but when differences in blood pressure are accounted for, estimated blood flow to the femur is approximately 1.9 times higher in cursorial birds than in mammals, possibly in relation to bipedalism and quadrupedalism, respectively. Femoral bone blood flow in both endothermic groups is estimated to be 50-100 times higher than in ectothermic reptiles. © 2014. Published by The Company of Biologists Ltd.

  10. Does platelet-rich plasma promote remodeling of autologous bone grafts used for augmentation of the maxillary sinus floor?

    NARCIS (Netherlands)

    Raghoebar, GM; Schortinghuis, J; Liem, RSB; Ruben, JL; van der Wal, JE; Vissink, A

    2005-01-01

    The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) on remodeling of autologous bone grafts used for augmentation of the floor of the maxillary sinus. In five edentulous patients suffering from insufficient retention of their upper denture related to a severely resorbed ma

  11. Conditional Knockout of the MicroRNA 17-92 Cluster in Type-I Collagen-Expressing Cells Decreases Alveolar Bone Size and Incisor Tooth Mechanical Properties.

    Science.gov (United States)

    Ibrahim, M; Mohan, S; Xing, M J; Kesavan, C

    2016-01-01

    To test the role of the miR17-92 (miR) cluster in dental bones, we evaluated the incisor tooth phenotype by micro-CT in 5- and 12-week-old conditional knockout (CKO) mice deficient in the miR17-92 cluster in type-I collagen-expressing cells and bone strength by finite element analysis. The incisor teeth of CKO mice showed a 23-30 % reduction in tissue volume and bone volume. Accordingly, the stiffness and failure load of incisor teeth assessed by finite element analysis showed an 18-40 % decrease in CKO compared to wild-type mice. A positive correlation between bone parameters and strength data suggests that the decreased mechanical properties of incisor teeth are due to decreased tissue volume and bone volume. Subsequently, we found that the width of alveolar bone was reduced by 25 % with a 16 % increase in periodontal ligament space, suggesting that the CKO mice are more susceptible to tooth movement. Since alveolar bone is populated primarily by osteoblast lineage cells, it is likely that the reduction in periosteal expansion of alveolar bone in the lower jaw of CKO mice results from decreased periosteal bone formation. Overall, our phenotype analysis demonstrates that the miR17-92 cluster is essential for development and maintenance of tooth strength by regulating its tooth size.

  12. Development of the lateral line canal system through a bone remodeling process in zebrafish.

    Science.gov (United States)

    Wada, Hironori; Iwasaki, Miki; Kawakami, Koichi

    2014-08-01

    The lateral line system of teleost fish is composed of mechanosensory receptors (neuromasts), comprising superficial receptors and others embedded in canals running under the skin. Canal diameter and size of the canal neuromasts are correlated with increasing body size, thus providing a very simple system to investigate mechanisms underlying the coordination between organ growth and body size. Here, we examine the development of the trunk lateral line canal system in zebrafish. We demonstrated that trunk canals originate from scales through a bone remodeling process, which we suggest is essential for the normal growth of canals and canal neuromasts. Moreover, we found that lateral line cells are required for the formation of canals, suggesting the existence of mutual interactions between the sensory system and surrounding connective tissues.

  13. Long-term outcomes of the use of allogeneic, radiation-sterilised bone blocks in reconstruction of the atrophied alveolar ridge in the maxilla and mandible.

    Science.gov (United States)

    Krasny, Marta; Krasny, Kornel; Fiedor, Piotr; Zadurska, Małgorzata; Kamiński, Artur

    2015-12-01

    Increasingly dental surgeons face the challenge of reconstruction of the height and/or thickness of the alveolar ridge as more and more patients wish to have permanent restoration of their dental defects based on intraosseous implants. Evaluation of human allogeneic bone tissue grafts in reconstruction of atrophied alveolar ridge as a pre-implantation procedure. The material comprised 21 patients aged 19-63, treated between 2009 and 2012 by the same surgeon. Restoration of bone tissue defects was performed with allogeneic, frozen, radiation-sterilised, corticocancellous blocks. The study included 26 grafting procedures with 7 procedures consisting in reconstruction of the alveolar ridge in the mandible and 19 in the maxilla. In all the cases the atrophied alveolar ridge was successfully reconstructed, which allowed placement of intraosseous implants in compliance with the initial treatment plan. After the treatment was completed the patients reported for follow-up annually. The average time of follow-up amounted to 39 months (28-50 months). None of the implants was lost during the follow-up period. There was one case of gingival recession causing aesthetics deterioration of the prosthetic restoration. In three cases the connector became unscrewed partially, which was corrected at the same visit. Frozen, radiation-sterilised, allogeneic bone blocks constitute good and durable bone-replacement material allowing effective and long-lasting reconstruction of the atrophied alveolar ridge to support durable, implant-based, prosthetic restoration.

  14. Remodeling of heat-treated cortical bone allografts for posterior lumbar interbody fusion: serial 10-year follow-up.

    Science.gov (United States)

    Muramatsu, Koichi; Hachiya, Yudo; Izawa, Hiroyuki; Yamada, Harumoto

    2012-12-01

    We have selected heat-treated bone allografts as the graft material since the Tokai Bone Bank, the first regional bone bank in Japan, was established in 1992. In this study, we examined changes in bone mineral density (BMD), and morphology observed by magnetic resonance imaging (MRI), and histological findings of bone grafts in cases followed up for 7-10 years after bone grafting to grasp the remodeling of heat-treated cortical bone allografts for posterior lumber interbody fusion (PLIF). BMD of bone grafts was reduced by half at 10 years after grafting. MRI revealed that bone grafts were indistinguishable initially in only 22.2% of cases, whereas after a lengthy period of 10 years distinguishable in many cases. Histologically, new bone formation at the graft-host interface was observed earlier, at 1 year after grafting, than that at the periphery of canals in the specimens. The laminated structure of the cortical bone eroded over time, and fragmented bone trabeculae were observed in the specimens at 8 years or longer after grafting, though necrotic bone still remained in some sites.

  15. Effects of β-Glucans Ingestion on Alveolar Bone Loss, Intestinal Morphology, Systemic Inflammatory Profile, and Pancreatic β-Cell Function in Rats with Periodontitis and Diabetes

    Directory of Open Access Journals (Sweden)

    Viviam de O. Silva

    2017-09-01

    Full Text Available This study aimed to evaluate the effects of β-glucan ingestion (Saccharomyces cerevisiae on the plasmatic levels of tumor necrosis factor-α (TNF-α and interleukin-10 (IL-10, alveolar bone loss, and pancreatic β-cell function (HOMA-BF in diabetic rats with periodontal disease (PD. Besides, intestinal morphology was determined by the villus/crypt ratio. A total of 48 Wistar rats weighing 203 ± 18 g were used. Diabetes was induced by the intraperitoneal injection of streptozotocin (80 mg/kg and periodontal inflammation, by ligature. The design was completely randomized in a factorial scheme 2 × 2 × 2 (diabetic or not, with or without periodontitis, and ingesting β-glucan or not. The animals received β-glucan by gavage for 28 days. Alveolar bone loss was determined by scanning electron microscopy (distance between the cementoenamel junction and alveolar bone crest and histometric analysis (bone area between tooth roots. β-glucan reduced plasmatic levels of TNF-α in diabetic animals with PD and of IL-10 in animals with PD (p < 0.05. β-glucan reduced bone loss in animals with PD (p < 0.05. In diabetic animals, β-glucan improved β-cell function (p < 0.05. Diabetic animals had a higher villus/crypt ratio (p < 0.05. In conclusion, β-glucan ingestion reduced the systemic inflammatory profile, prevented alveolar bone loss, and improved β-cell function in diabetic animals with PD.

  16. The histopathological and morphometric investigation of the effects of systemically administered boric acid on alveolar bone loss in ligature-induced periodontitis in diabetic rats.

    Science.gov (United States)

    Balci Yuce, Hatice; Toker, Hulya; Goze, Fahrettin

    2014-11-01

    The purpose of this study was to evaluate the effects of systemically administered boric acid on alveolar bone loss, histopathological changes and oxidant/antioxidant status in ligature-induced periodontitis in diabetic rats. Forty-four Wistar rats were divided into six experimental groups: (1) non-ligated (NL, n = 6) group, (2) ligature only (LO, n = 6) group, (3) Streptozotocin only (STZ, n = 8) group, (4) STZ and ligature (STZ+LO, n = 8) group, (5) STZ, ligature and systemic administration of 15 mg/kg/day boric acid for 15 days (BA15, n = 8) group and (6) STZ, ligature and systemic administration of 30 mg/kg/day boric acid for 15 days (BA30, n = 8) group. Diabetes mellitus was induced by 60 mg/kg streptozotocin. Silk ligatures were placed at the gingival margin of lower first molars of the mandibular quadrant. The study duration was 15 days after diabetes induction and the animals were sacrificed at the end of this period. Changes in alveolar bone levels were clinically measured and tissues were histopathologically examined. Serum total antioxidant status (TAS), total oxidant status (TOS), calcium (Ca) and magnesium (Mg) levels and oxidative stress index (OSI) were evaluated. Primary outcome was alveolar bone loss. Seconder outcome (osteoblast number) was also measured. At the end of 15 days, the alveolar bone loss was significantly higher in the STZ+LO group compared to the other groups (p boric acid and STZ+LO 30 mg/kg boric acid groups (p > 0.05). Systemically administered boric acid significantly decreased alveolar bone loss compared to the STZ+LO group (p 0.05). The OSI values of the BA30 group were significantly lower than the STZ+LO group (p 0.05). Within the limits of this study, it can be suggested that BA, when administered systemically, may reduce alveolar bone loss in the diabetic rat model.

  17. Effect of biphasic calcium phosphate nanocomposite on healing of surgically created alveolar bone defects in beagle dogs

    Science.gov (United States)

    Wang, Lanlei; Guan, Aizhong; Shi, Han; Chen, Yangxi; Liao, Yunmao

    2009-09-01

    The aim of the present study was to investigate the effect of porous biphasic calcium phosphate nanocomposite (nanoBCP) scaffolds bioceramic. Alveolar bone defects were surgically created bilaterally at the buccal aspects of the upper second premolar in fourteen beagle dogs. After root conditioning with ethylenediaminetetraacetate (EDTA), nanoBCP was randomly filled in the defects and nothing was put into the contralaterals as controls. Dogs were killed at the 12th weeks. Histological observations were processed through a light microscopy. The results revealed that a great amount of functional periodontal fissures formed in the defects in the nanoBCP groups while minimal bone took shape in the controls. In this study, nanoBCP has proved to work well as a biocompatible and osteoconductive scaffold material to promote periodontal regeneration effectively.

  18. Computerized system to measure interproximal alveolar bone levels in epidemiologic, radiographic investigations. II. Intra- and inter-examinar variation study

    Energy Technology Data Exchange (ETDEWEB)

    Wouters, F.R.; Frithiof, L.; Soeder, P.Oe.; Hellden, L.; Lavstedt, S.; Salonen, L.

    1988-01-01

    The study was aimed at analyzing intra- and inter-examiner variations in computerized measurement and in non-measurability of alveolar bone level in a cross-sectional, epidemiologic material. At each interproximal tooth surface, alveolar bone height in percentage of root length (B/R) and tooth length (B/T) were determined twice by one examiner and once by a second examiner from X5-magnified periapical radiographs. The overall intra- and inter-examiner variations in measurement were 2.85% and 3.84% of root length and 1.97% and 2.82% of tooth length, respectively. The varations were different for different tooth groups and for different degrees of severity of marginal periodontitis. The overall proportions on non-measurable tooth surfaces varied with examiner from 32% to 39% and from 43% to 48% of the available interproximal tooth surfaces for B/R and B/T, respectively. With regard to the level of reliability, the computerized method reported is appropriate to cross-sectional, epidemiologic investigations from radiographs.

  19. 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.

  20. Variations in the buccal-lingual alveolar bone thickness of impacted mandibular third molar: our classification and treatment perspectives.

    Science.gov (United States)

    Ge, Jing; Zheng, Jia-Wei; Yang, Chi; Qian, Wen-Tao

    2016-01-13

    Selecting either buccal or lingual approach for the mandibular third molar surgical extraction has been an intense debate for years. The aim of this observational retrospective study was to classify the molar based on the proximity to the external cortical bone, and analyze the position of inferior alveolar canal (IAC) of each type. Cone-beam CT (CBCT) data of 110 deeply impacted mandibular third molars from 91 consecutive patients were analyzed. A new classification based on the mean deduction value (MD) of buccal-lingual alveolar bone thickness was proposed: MD≥1 mm was classified as buccal position, 1 mm>MD>-1 mm was classified as central position, MD≤-1 mm was classified as lingual position. The study samples were distributed as: buccal position (1.8%) in 2 subjects, central position (10.9%) in 12 and lingual position (87.3%) in 96. Ninety-six molars (87.3%) contacted the IAC. The buccal and inferior IAC course were the most common types in impacted third molar, especially in lingually positioned ones. Our study suggested that amongst deeply impacted mandibular third molars, lingual position occupies the largest proportion, followed by the central, and then the buccal type.

  1. Root proximity as a risk factor for progression of alveolar bone loss: the Veterans Affairs Dental Longitudinal Study.

    Science.gov (United States)

    Kim, Taera; Miyamoto, Takanari; Nunn, Martha E; Garcia, Raul I; Dietrich, Thomas

    2008-04-01

    The purpose of the present longitudinal study was to evaluate the association between root proximity and the risk for alveolar bone loss (ABL). We used data from the Veterans Affairs Dental Longitudinal Study, a closed-panel longitudinal cohort study of 1,231 men enrolled in 1968 with triennial follow-up examinations. Periapical radiographs of mandibular incisors from subjects with > or =10 years of follow-up were selected. Interradicular distance (IRD) at the cemento-enamel junction and alveolar bone levels at baseline and last follow-up were measured using digitized radiographs. The rate of progressive ABL was determined and expressed as millimeters per 10 years. Site-specific multivariate regression models were fit to evaluate the association between IRD and ABL rate, adjusting for age and smoking. Empirical standard errors and generalized estimating equations were used to account for the correlation among sites within subjects. There were 473 dentate subjects, aged 28 to 71 years at baseline, with > or =10 years of follow-up data available for analyses. The mean follow-up time was 23 years. The mean IRD was 1.0 +/- 0.3 mm, and the mean ABL rate during 10 years was 0.61 +/- 0.59 mm. There was a significant non-linear association between IRD and ABL rate (P or =0.8 mm, sites with IRD or =0.5 mm of bone during 10 years (relative risk: 1.28 [95% CI: 1.11 to 1.48]) and 56% (95% CI: 11% to 117%) more likely to lose > or =1.0 mm of bone during 10 years (relative risk: 1.56 [95% CI: 1.11 to 2.17]). IRD loss in mandibular anterior teeth. Measurement of IRD may have important prognostic value in making treatment decisions.

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

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    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.

  3. Influence of preservation of the alveolar ridge on delayed implants after extraction of teeth with different defects in the buccal bone.

    Science.gov (United States)

    Pang, Chaoyuan; Ding, Yuxiang; Hu, Kaijin; Zhou, Hongzhi; Qin, Ruifeng; Hou, Rui

    2016-02-01

    Our aim was to evaluate the influence of preservation of the alveolar ridge on delayed implants with different defects in the buccal bone. We enrolled 60 patients who had one posterior mandibular tooth extracted. Cone-beam computed tomography (CT) was used to measure the buccal bone defects in the alveolar ridge before the tooth was extracted (level A=3 to 5 mm, and level B=more than 5 mm). After the tooth had been extracted, the socket either had the alveolar ridge preserved (trial group) or it was left to heal spontaneously (control group). The changes in the dimensions of the alveolar ridge from preoperatively to 6 months postoperatively were evaluated by cone-beam CT. Suitable implants were inserted 6 months later, and their length and diameter recorded. The implant stability quotient was evaluated for the following 3 months. The dimensions of the bone in the alveolar ridge in the trial group were significantly less than those in the control groups in both levels. Fifty-seven patients required implants (except 3 in level B in the control group). There were more longer and wider implants in the trial group than in the control group in Level B. 3 months after implantation, there were no significant differences in implant stability quotients between the groups, though in the control group, Level B, the mean (SD) value was 69.50 (1.00) while in the other groups values were all above 70 at 3 months. We conclude that when the defect in the buccal bone was more than 5mm, the alveolar ridge preservation demonstrated a remarkable effect in preserving the alveolar ridge dimension and delayed implantation.

  4. Posterior maxillary sandwich osteotomy combined with sinus grafting with bone morphogenetic protein-2 for alveolar reconstruction for dental implants: report of four cases.

    Science.gov (United States)

    Jensen, Ole T; Cottam, Jared

    2013-01-01

    Four patients underwent posterior sandwich osteotomy combined with sinus floor grafting using bone morphogenetic protein-2 and other grafting materials. The patients were treated over a period of 4 years. Two to four implants were placed in each site subsequently. Of the 12 implants placed, none failed. Alveolar crest bone levels appeared to be stable over time, with an average vertical gain of about 5 mm. Overall vertical gain, including the sinus graft, exceeded 13 mm in all patients. The procedure appears to hold promise for combined vertical alveolar defects and prominent pneumatization of the posterior maxilla.

  5. Aging and estrogen status: a possible endothelium-dependent vascular coupling mechanism in bone remodeling.

    Directory of Open Access Journals (Sweden)

    Rhonda D Prisby

    Full Text Available Bone loss with aging and menopause may be linked to vascular endothelial dysfunction. The purpose of the study was to determine whether putative modifications in endothelium-dependent vasodilation of the principal nutrient artery (PNA of the femur are associated with changes in trabecular bone volume (BV/TV with altered estrogen status in young (6 mon and old (24 mon female Fischer-344 rats. Animals were divided into 6 groups: 1 young intact, 2 old intact, 3 young ovariectomized (OVX, 4 old OVX, 5 young OVX plus estrogen replacement (OVX+E2, and 6 old OVX+E2. PNA endothelium-dependent vasodilation was assessed in vitro using acetylcholine. Trabecular bone volume of the distal femoral metaphysis was determined by microCT. In young rats, vasodilation was diminished by OVX and restored with estrogen replacement (intact, 82±7; OVX, 61±9; OVX+E2, 90±4%, which corresponded with similar modifications in BV/TV (intact, 28.7±1.6; OVX, 16.3±0.9; OVX+E2, 25.7±1.4%. In old animals, vasodilation was unaffected by OVX but enhanced with estrogen replacement (intact, 55±8; OVX, 59±7; OVX+E2, 92±4%. Likewise, modifications in BV/TV followed the same pattern (intact, 33.1±1.6; OVX, 34.4±3.7; OVX+E2, 42.4±2.1%. Furthermore, in old animals with low endogenous estrogen (i.e., intact and old OVX, vasodilation was correlated with BV/TV (R(2 = 0.630; P<0.001. These data demonstrate parallel effects of estrogen on vascular endothelial function and BV/TV, and provide for a possible coupling mechanism linking endothelium-dependent vasodilation to bone remodeling.

  6. Bone-Remodeling Transcript Levels Are Independent of Perching in End-of-Lay White Leghorn Chickens

    Directory of Open Access Journals (Sweden)

    Maurice D. Dale

    2015-01-01

    Full Text Available Osteoporosis is a bone disease that commonly results in a 30% incidence of fracture in hens used to produce eggs for human consumption. One of the causes of osteoporosis is the lack of mechanical strain placed on weight-bearing bones. In conventionally-caged hens, there is inadequate space for chickens to exercise and induce mechanical strain on their bones. One approach is to encourage mechanical stress on bones by the addition of perches to conventional cages. Our study focuses on the molecular mechanism of bone remodeling in end-of-lay hens (71 weeks with access to perches. We examined bone-specific transcripts that are actively involved during development and remodeling. Using real-time quantitative PCR, we examined seven transcripts (COL2A1 (collagen, type II, alpha 1, RANKL (receptor activator of nuclear factor kappa-B ligand, OPG (osteoprotegerin, PTHLH (PTH-like hormone, PTH1R (PTH/PTHLH type-1 receptor, PTH3R (PTH/PTHLH type-3 receptor, and SOX9 (Sry-related high mobility group box in phalange, tibia and femur. Our results indicate that the only significant effect was a difference among bones for COL2A1 (femur > phalange. Therefore, we conclude that access to a perch did not alter transcript expression. Furthermore, because hens have been used as a model for human bone metabolism and osteoporosis, the results indicate that bone remodeling due to mechanical loading in chickens may be a product of different pathways than those involved in the mammalian model.

  7. Tissue-engineered bone repairs sheep alveolar bone defects%组织工程化骨修复羊牙槽骨缺损***

    Institute of Scientific and Technical Information of China (English)

    张琴; 杨川博; 何惠宇; 崔杰; 杨楠; 马文渊

    2013-01-01

    BACKGROUND:Fol owing physicochemical treatment and high-temperature calcinations, heterogeneous biological bone becomes a ceramic-like heterologous bone forming a similar structure to the human bone that is a natural network pore structure, which is conducive to seed cel adhesion and proliferation. OBJECTIVE:To observe the feasibility of constructing tissue-engineered bone through combination of sintered bone and bone marrow mesenchymal stem cel s to repair alveolar defects. METHODS:Sheep bone marrow mesenchymal stem cel s as seed cel s were combined with the high temperature sintered bone as scaffold materials to construct tissue-engineered bone. Under general anesthesia, sheep bilateral mandibular first premolars were removed in batches, the alveolar ridge space between the distal root and mesial root of the second premolar to form a bone defect area of 5 mm×5 mm×5 mm. Twelve experimental sheep were equal y randomized into tissue-engineered bone group and sintered bone group, which were implanted with tissue-engineered bone and sintered bone, respectively, at the left surgical area of the mandible. The right surgical area was considered as blank control group. RESULTS AND CONCLUSION:After high-temperature calcinations, the sintered bone was chalk in color, exhibiting a porous structure as the natural cancel ous bone. The porosity was (66.10±1.32)%, and the pore size was between 137.44μm and 538.72μm. After 24 hours of bone marrow mesenchymal stem cel s inoculated to the sintered bone, a large number of cel s are visible adherent to the scaffold;up to day 7, extracel ular matrix was secreted and there was no clear boundary between the cel s and the matrix. X-ray films showed that the tissue-engineered bone and pure sintered bone implants were embedded in the surgical area, and there was a low-density shadow at the edge of the sintered bone. Hematoxylin-eosin staining showed bone trabecular formation at the experimental side, but no obvious bone formation at

  8. Effects of resveratrol supplementation on bone growth in young rats and microarchitecture and remodeling in ageing rats.

    Science.gov (United States)

    Lee, Alice M C; Shandala, Tetyana; Nguyen, Long; Muhlhausler, Beverly S; Chen, Ke-Ming; Howe, Peter R; Xian, Cory J

    2014-12-16

    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. Using rat models, the current study investigated the potential effects of resveratrol supplementation during the rapid postnatal growth period and in late adulthood (early ageing) on bone microarchitecture and metabolism. In the growth trial, 4-week-old male hooded Wistar rats on a normal chow diet were given resveratrol (2.5 mg/kg/day) or vehicle control for 5 weeks. In the ageing trial, 6-month-old male hooded Wistar rats were treated with resveratrol (20 mg/kg/day) or vehicle for 3 months. Treatment effects in the tibia were examined by μ-computer tomography (μ-CT) analysis, bone histomorphometric measurements and reverse transcription-polymerase chain reaction (RT-PCR) gene expression analysis. Resveratrol treatment did not affect trabecular bone volume and bone remodeling indices in the youth animal model. Resveratrol supplementation in the early ageing rats tended to decrease trabecular bone volume, Sirt1 gene expression and increased expression of adipogenesis-related genes in bone, all of which were statistically insignificant. However, it decreased osteocalcin expression (p = 0.03). Furthermore, serum levels of bone resorption marker C-terminal telopeptides type I collagen (CTX-1) were significantly elevated in the resveratrol supplementation group (p = 0.02) with no changes observed in serum levels of bone formation marker alkaline phosphatase (ALP). These results in rat models suggest that resveratrol supplementation does not significantly affect bone volume

  9. Effects of Resveratrol Supplementation on Bone Growth in Young Rats and Microarchitecture and Remodeling in Ageing Rats

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    Alice M. C. Lee

    2014-12-01

    Full Text Available 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. Using rat models, the current study investigated the potential effects of resveratrol supplementation during the rapid postnatal growth period and in late adulthood (early ageing on bone microarchitecture and metabolism. In the growth trial, 4-week-old male hooded Wistar rats on a normal chow diet were given resveratrol (2.5 mg/kg/day or vehicle control for 5 weeks. In the ageing trial, 6-month-old male hooded Wistar rats were treated with resveratrol (20 mg/kg/day or vehicle for 3 months. Treatment effects in the tibia were examined by μ-computer tomography (μ-CT analysis, bone histomorphometric measurements and reverse transcription-polymerase chain reaction (RT-PCR gene expression analysis. Resveratrol treatment did not affect trabecular bone volume and bone remodeling indices in the youth animal model. Resveratrol supplementation in the early ageing rats tended to decrease trabecular bone volume, Sirt1 gene expression and increased expression of adipogenesis-related genes in bone, all of which were statistically insignificant. However, it decreased osteocalcin expression (p = 0.03. Furthermore, serum levels of bone resorption marker C-terminal telopeptides type I collagen (CTX-1 were significantly elevated in the resveratrol supplementation group (p = 0.02 with no changes observed in serum levels of bone formation marker alkaline phosphatase (ALP. These results in rat models suggest that resveratrol supplementation does not significantly affect bone

  10. Numerical investigations on the strain-adaptive bone remodelling in the periprosthetic femur: Influence of the boundary conditions

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    Stukenborg-Colsman Christina

    2009-04-01

    Full Text Available Abstract Background There are several numerical investigations on bone remodelling after total hip arthroplasty (THA on the basis of the finite element analysis (FEA. For such computations certain boundary conditions have to be defined. The authors chose a maximum of three static load situations, usually taken from the gait cycle because this is the most frequent dynamic activity of a patient after THA. Materials and methods The numerical study presented here investigates whether it is useful to consider only one static load situation of the gait cycle in the FE calculation of the bone remodelling. For this purpose, 5 different loading cases were examined in order to determine their influence on the change in the physiological load distribution within the femur and on the resulting strain-adaptive bone remodelling. First, four different static loading cases at 25%, 45%, 65% and 85% of the gait cycle, respectively, and then the whole gait cycle in a loading regime were examined in order to regard all the different loadings of the cycle in the simulation. Results The computed evolution of the apparent bone density (ABD and the calculated mass losses in the periprosthetic femur show that the simulation results are highly dependent on the chosen boundary conditions. Conclusion These numerical investigations prove that a static load situation is insufficient for representing the whole gait cycle. This causes severe deviations in the FE calculation of the bone remodelling. However, accompanying clinical examinations are necessary to calibrate the bone adaptation law and thus to validate the FE calculations.

  11. Simulation of multi-stage nonlinear bone remodeling induced by fixed partial dentures of different configurations: a comparative clinical and numerical study.

    Science.gov (United States)

    Liao, Zhipeng; Yoda, Nobuhiro; Chen, Junning; Zheng, Keke; Sasaki, Keiichi; Swain, Michael V; Li, Qing

    2017-04-01

    This paper aimed to develop a clinically validated bone remodeling algorithm by integrating bone's dynamic properties in a multi-stage fashion based on a four-year clinical follow-up of implant treatment. The configurational effects of fixed partial dentures (FPDs) were explored using a multi-stage remodeling rule. Three-dimensional real-time occlusal loads during maximum voluntary clenching were measured with a piezoelectric force transducer and were incorporated into a computerized tomography-based finite element mandibular model. Virtual X-ray images were generated based on simulation and statistically correlated with clinical data using linear regressions. The strain energy density-driven remodeling parameters were regulated over the time frame considered. A linear single-stage bone remodeling algorithm, with a single set of constant remodeling parameters, was found to poorly fit with clinical data through linear regression (low [Formula: see text] and R), whereas a time-dependent multi-stage algorithm better simulated the remodeling process (high [Formula: see text] and R) against the clinical results. The three-implant-supported and distally cantilevered FPDs presented noticeable and continuous bone apposition, mainly adjacent to the cervical and apical regions. The bridged and mesially cantilevered FPDs showed bone resorption or no visible bone formation in some areas. Time-dependent variation of bone remodeling parameters is recommended to better correlate remodeling simulation with clinical follow-up. The position of FPD pontics plays a critical role in mechanobiological functionality and bone remodeling. Caution should be exercised when selecting the cantilever FPD due to the risk of overloading bone resorption.

  12. Characterization of a new fish-derived bioactive neuropeptide involved in bone remodelling. Its physiological function and therapeutic potential.

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    Paula Suarez-Bregua

    2014-04-01

    Full Text Available A complex network of autocrine and paracrine signals, hormones and neuronal factors preserve the structural integrity of the skeleton and regulate mineral metabolism in vertebrates. We have characterized a new neuropeptide belonging to parathyroid hormone (PTH family. PTH family members are known to play a key role in maintaining mineral homeostasis, bone remodeling and in regulating embryonic development of skeleton and other tissues. This new neuropeptide is synthesized by two clusters of neurons located in lateral hypothalamus as showed in whole mount in situ hybridization. The functional characterization of the gene using a stable transgenic line revealed its key role in the regulation of bone mineral density. Moreover, phylogenetic analyses and comparative genomics results of conserved synteny reveal that this new neuropeptide is a new ohnolog of the PTH family present in teleosts and some tetrapods like chicken, but absent in mammals . Our findings suggest a new brain to bone pathway, where neuronal factors from hypothalamus signal to receptors on bone cells promoting bone remodeling. Further investigations about this new neuropeptide system would be relevant for developing therapies for bone mineral disorders in humans, since this neuropeptide has a conserved domain similar to other PTH-related peptides which have anabolic effects on bone.

  13. 咀嚼压力增强对大鼠牙槽骨白细胞介素-1β表达的影响%Effect of increased bite force on the expression of IL-1β in rat alveolar bone osteoblasts

    Institute of Scientific and Technical Information of China (English)

    袁林; 周伟东; 赵云凤

    2001-01-01

    目的检测大鼠牙槽骨成骨细胞中IL-1β在正常及增强咀嚼压力状态下的动态表达,探讨IL-1β在牙槽骨改建中的分子机制。方法采用HE染色和免疫组化的方法,观察牙周形态变化以及牙槽骨成骨细胞中IL-1β蛋白表达。结果生理限度内咀嚼压力增强时,形态学显示大鼠牙周膜增宽、牙槽骨新骨形成;免疫组化观察到成骨细胞中IL-1β表达较正常咀嚼压力时明显增强。结论咀嚼压力增强促使牙周组织产生IL-1β明显增多,诱发了破骨功能,同时,还激活了成骨功能。提示IL-1β在咀嚼压力影响牙槽骨改建的过程中起着重要的调节作用。%Objective To explore the molecular mechanism of alveolar bone remodeling by studying the dynamic changes of IL- 1β expression in rat alveolar bone osteoblasts. Methods Rat models of increased bite force of the back teeth were established, and the expression of IL-1β in the alveolar bone osteoblasts were determined by HE staining and immunohistochemistry. Observation of the changes in the histological morphology of the periodontium was conducted microscopically. Rats with normal bite force served as control. Results The increase of bite force (within the physiological limit) induced the widening of the periodontal ligament and the osteogenesis in the alveolar bone. Significant enhancement of IL-1β expression was observed in the osteoblasts of rats with increased bite force, in comparison with that in the rats with normal bite force. Conclusion Increased bite force causes higher expression levels of IL-1β in the alveolar bone osteoblasts, initiating the destruction process of the bone but simultaneously the activation of the ossification, suggesting that IL-1β plays an important role in the regulation of periodontium remodeling in response to changes in the bite force

  14. The Mechanical Properties and Biometrical Effect of 3D Preformed Titanium Membrane for Guided Bone Regeneration on Alveolar Bone Defect

    Directory of Open Access Journals (Sweden)

    So-Hyoun Lee

    2017-01-01

    Full Text Available The purpose of this study is to evaluate the effect of three-dimensional preformed titanium membrane (3D-PFTM to enhance mechanical properties and ability of bone regeneration on the peri-implant bone defect. 3D-PFTMs by new mechanically compressive molding technology and manually shaped- (MS- PFTMs by hand manipulation were applied in artificial peri-implant bone defect model for static compressive load test and cyclic fatigue load test. In 12 implants installed in the mandibular of three beagle dogs, six 3D-PFTMs, and six collagen membranes (CM randomly were applied to 2.5 mm peri-implant buccal bone defect with particulate bone graft materials for guided bone regeneration (GBR. The 3D-PFTM group showed about 7.4 times higher mechanical stiffness and 5 times higher fatigue resistance than the MS-PFTM group. The levels of the new bone area (NBA, %, the bone-to-implant contact (BIC, %, distance from the new bone to the old bone (NB-OB, %, and distance from the osseointegration to the old bone (OI-OB, % were significantly higher in the 3D-PFTM group than the CM group (p<.001. It was verified that the 3D-PFTM increased mechanical properties which were effective in supporting the space maintenance ability and stabilizing the particulate bone grafts, which led to highly efficient bone regeneration.

  15. Cyclophilin A (CypA) is associated with the inflammatory infiltration and alveolar bone destruction in an experimental periodontitis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Lihua [Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China); Li, Chengzhang, E-mail: l56cz@hotmail.com [Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China); Department of Periodontology, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China); Cai, Cia [Department of Periodontology, School and Hospital of Stomatology, Zhejiang University, 395 Yan An Road, Hangzhou 310006 (China); Xiang, Junbo [Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China); Cao, Zhengguo, E-mail: jery7677@hotmail.com [Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China); Department of Periodontology, School and Hospital of Stomatology, Wuhan University, 237 Luo Yu Road, Hongshan District, Wuhan 430079 (China)

    2010-01-01

    Background and objective: CypA is able to regulate inflammatory responses and MMPs production via interaction with its cell surface receptor, EMMPRIN. This study aimed to address the possible association of CypA with pathological inflammation and destruction of periodontal tissues, and whether CypA-EMMPRIN interaction exists in periodontitis. Materials and methods: Experimental periodontitis was induced by ligation according to our previous method. Histological and radiographic examinations were performed. Western blot was used to detect CypA and EMMPRIN expressions in gingival tissues. Immunohistochemistry was applied for CypA, EMMPRIN, MMP-1, MMP-2, MMP-9, as well as cell markers of macrophage, lymphocyte and neutrophil. CypA expression, alveolar bone loss, and inflammatory infiltrations were quantified followed by correlation analyses. Results: Western blot revealed that CypA and EMMRPIN expressions were dramatically elevated in inflamed gingival tissues (ligature group) as compared to healthy gingival tissues (control group). The enhanced CypA and EMMPRIN expressions were highly consistent in cell localization on seriate sections. They were permanently co-localized in infiltrating macrophages and lymphocytes, as well as osteoclasts and osteoblasts in interradicular bone, but rarely expressed by infiltrating neutrophils. MMP-1, MMP-2, and MMP-9 expressions were also sharply increased in inflamed gingiva. MMP-2 and MMP-9 were mainly over-expressed by macrophages, while MMP-1 was over-produced by fibroblasts and infiltrating cells. The number of CypA-positive cells was strongly correlated with the ACJ-AC distance (r = 0.839, p = 0.000), the number of macrophages (r = 0.972, p = 0.000), and the number of lymphocytes (r = 0.951, p = 0.000). Conclusion: CypA is associated with the inflammatory infiltration and alveolar bone destruction of periodontitis. CypA-EMMPRIN interaction may exist in these pathological processes.

  16. Osteocyte apoptosis and absence of bone remodeling in human auditory ossicles and scleral ossicles of lower vertebrates: a mere coincidence or linked processes?

    Science.gov (United States)

    Palumbo, Carla; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Ferretti, Marzia

    2012-03-01

    Considering the pivotal role as bone mechanosensors ascribed to osteocytes in bone adaptation to mechanical strains, the present study analyzed whether a correlation exists between osteocyte apoptosis and bone remodeling in peculiar bones, such as human auditory ossicles and scleral ossicles of lower vertebrates, which have been shown to undergo substantial osteocyte death and trivial or no bone turnover after cessation of growth. The investigation was performed with a morphological approach under LM (by means of an in situ end-labeling technique) and TEM. The results show that a large amount of osteocyte apoptosis takes place in both auditory and scleral ossicles after they reach their final size. Additionally, no morphological signs of bone remodeling were observed. These facts suggest that (1) bone remodeling is not necessarily triggered by osteocyte death, at least in these ossicles, and (2) bone remodeling does not need to mechanically adapt auditory and scleral ossicles since they appear to be continuously submitted to stereotyped stresses and strains; on the contrary, during the resorption phase, bone remodeling might severely impair the mechanical resistance of extremely small bony segments. Thus, osteocyte apoptosis could represent a programmed process devoted to make stable, when needed, bone structure and mechanical resistance.

  17. BST2 Mediates Osteoblast Differentiation via the BMP2 Signaling Pathway in Human Alveolar-Derived Bone Marrow Stromal Cells.

    Science.gov (United States)

    Yoo, Su-Hyang; Kim, Jae Goo; Kim, Beom-Su; Lee, Jun; Pi, Sung-Hee; Lim, Hyun-Dae; Shin, Hong-In; Cho, Eui-Sic; You, Hyung-Keun

    2016-01-01

    The molecular mechanisms controlling the differentiation of bone marrow stromal stem cells into osteoblasts remain largely unknown. In this study, we investigated whether bone marrow stromal antigen 2 (BST2) influences differentiation toward the osteoblasts lineage. BST2 mRNA expression in human alveolar-derived bone marrow stromal cells (hAD-BMSCs) increased during differentiation into osteoblasts. hAD-BMSCs differentiation into osteoblasts and the mRNA expression of the bone-specific markers alkaline phosphatase, collagen type α 1, bone sialoprotein, osteocalcin, and osterix were reduced by BST2 knockdown using siRNA. Furthermore, BST2 knockdown in hAD-BMSCs resulted in decreased RUNX2 mRNA and protein expression. We hypothesized that BST2 is involved in differentiation of into osteoblasts via the BMP2 signaling pathway. Accordingly, we evaluated the mRNA expression levels of BMP2, BMP receptors (BMPR1 and 2), and the downstream signaling molecules SMAD1, SMAD4, and p-SMAD1/5/8 in BST2 knockdown cells. BMP2 expression following the induction of differentiation was significantly lower in BST2 knockdown cells than in cells treated with a non-targeting control siRNA. Similar results were found for the knockdown of the BMP2 receptor- BMPR1A. We also identified significantly lower expression of SMAD1, SMAD4, and p-SMAD1/5/8 in the BST2 knockdown cells than control cells. Our data provide the first evidence that BST2 is involved in the osteogenic differentiation of bone marrow stromal cells via the regulation of the BMP2 signaling pathway.

  18. Histomorphometric Study of Alveolar Bone Healing in Rats Fed a Boron-Deficient Diet

    Science.gov (United States)

    Bone healing after tooth extraction in rats is a suitable experimental model to study bone formation. Thus, we performed a study to determine the effects of boron (B) deficiency on bone healing by using this model. Weanling Wistar rats were divided into two groups: control (+B; 3 mg B/kg diet), and ...

  19. Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion*

    Science.gov (United States)

    Guo, Qing-yuan; Zhang, Shi-jie; Liu, Hong; Wang, Chun-ling; Wei, Fu-lan; Lv, Tao; Wang, Na-na; Liu, Dong-xu

    2011-01-01

    Objective: The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage. Methods: Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted. Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion. A computed tomography (CT) scan was performed after placement of the miniscrews and treatment. The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone. Results: The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm, respectively, and (1.34±0.74) mm of upper central incisor intrusion. Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm, respectively, and the percentages were (6.49±3.54)% and (27.42±9.77)%, respectively. The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°, respectively. Conclusions: Thus, for adult patients with bimaxillary protrusion, mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion. Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss. PMID:22135148

  20. Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion

    Institute of Scientific and Technical Information of China (English)

    Qing-yuan GUO; Shi-jie ZHANG; Hong LIU; Chun-ling WANG; Fu-lan WEI; Tao LV; Na-na WANG; Dong-xu LIU

    2011-01-01

    Objective: The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage.Methods: Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted.Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion.A computed tomography (CT) scan was performed after placement of the miniscrews and treatment.The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone.Results: The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm,respectively,and (1.34±0.74) mm of upper central incisor intrusion.Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm,respectively,and the percentages were (6.49±3.54)% and (27.42±9.77)%,respectively.The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°,respectively.Conclusions: Thus,for adult patients with bimaxillary protrusion,mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion.Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.

  1. Thoracic bone remodeling after minimally invasive repair for pectus excavatum in adults and its clinical efficacy

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    Ji-fu LIU

    2012-04-01

    Full Text Available Objective To study thoracic bone remodeling after minimally invasive corrective surgery for pectus excavatum (PE in adults and ascertain its clinical efficacy. Methods A total of 82 patients aged 18 to 57 (23.5±6.1 were enrolled in this study. There were 67 male patients and 15 female patients. The symmetric type (Ⅰ type composed of 37 cases, whereas the nonsymmetric type (Ⅱ type comprised 45 cases. Haller index (HI was 3.2 to 11.8. Under general anesthesia, incisions located on looth sides of the mid-axillary line were made in all patients. The prepared supporting bar was inserted behind the sternum by videoassisted thoracoscopic monitoring (one bar for 60 patients and two bars for 22 patients. All patients were checked by chest CT scan pre-operation and 1 week post-operation to create a three-dimensional reconstruction thoracic image. In the sagittal plane, the center line of the body of the thoracic vertebrae was regarded as the incision line. The distance was measured between the sternum and the frontal edge of the body of the thoracic vertebrae. The condition of the displacement of the heart was also observed. Results When one bar was used, the middle and the inferior extremity of the mid-sternum was moved forward for 8.69 and 15.69mm, respectively, after correction. There was significant difference compared with that of the pre-operation (P < 0.01. However, the upper extremity of the mid-sternum and upper and inferior extremities of the manubrium were moved forward to 2.39, -2.38, and 1.44mm, which did not exhibit obvious difference compared with the values taken before the operation. When two bars were used for the patients, the inferior extremity of the manubrium and each of upper, middle, and inferior extremities of the mid-sternum showed a forward displacement for 10.8, 12.45, 17.61, and 20.62mm, respectively. There was significant difference compared with the pre-operative values (P < 0.001. The upper extremity of the

  2. 应用AutoCAD定量分析牙槽骨水平的研究%Quantitative analysis of alveolar bone level by Auto CAD software

    Institute of Scientific and Technical Information of China (English)

    任秀云; 乔月娥; 兰晓敏

    2012-01-01

    Objective To establish and evaluale a new quanlilalive melhod for measurement of alveolar bone level. Methods The area from ihe cemenlo-enamel junction ( CEJ) Lo ihe alveolar bone level ( BL) and ihe area from ihe CEJ Lo ihe rool apex (RA)on ihe panoramic radiographs were measured by AuloCAD software. The dislance belween ihe CEJ and BL and ihe dislance belween ihe CEJ and RA were measured. The proporlional values of ihe area and dislance of ihe alveolar bone loss were analyzed. Results A lolal of 336 areas and 672 linear distances were measured. There was high consistency belween ihe Iradilional lenglh ralios of ihe alveolar bone loss and ihe area ralios oblained by AuloCAD. Pearson's correlation coefficient was 0. 921 ( P 0.05),组内相关系数为0.994(P<0.001),Pearson相关系数为0.988(P<0.001).结论 在二维图像的X线片中,用AutoCAD软件测量牙槽骨吸收面积比值可作为定量评价牙槽骨水平的新方法.

  3. Comparison of the changes of alveolar bone thickness in maxillary incisor area in extraction and non-extraction cases: computerized tomography evaluation

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Barroso Picanço

    2013-10-01

    Full Text Available OBJECTIVE: To compare, through computed tomography, alveolar bone thickness changes at the maxillary incisors area during orthodontic treatment with and without tooth extraction. METHODS: Twelve patients were evaluated. They were divided into 2 groups: G1 - 6 patients treated with extraction of right and left maxillary first premolars, with mean initial age of 15.83 years and mean treatment length of 2.53 years; G2 - 6 patients treated without extraction, with mean initial age of 18.26 years and mean treatment length of 2.39 years. Computed tomographies, lateral cephalograms and periapical radiographs were used at the beginning of the treatment (T1 and 18 months after the treatment had started (T2. Extraction space closure occurred in the extraction cases. Intragroup and intergroup comparisons were performed by dependent and independent t test, respectively. RESULTS: In G1, the central incisor was retracted and uprighted, while in G2 this tooth showed vestibularization. Additionally, G1 presented a higher increase of labial alveolar bone thickness at the cervical third in comparison with G2. The incidence of root resorption did not present significant differences between groups. CONCLUSION: There were no changes in alveolar bone thickness when extraction and nonextraction cases were compared, except for the labial alveolar bone thickness at the cervical third of maxillary incisors.

  4. 髂骨块状骨植骨术修复恒牙列牙槽突裂的短期临床观察%Alveolar bulk bone grafting:A new surgical approach for alveolar cleft

    Institute of Scientific and Technical Information of China (English)

    唐燕驰; 杜一飞; 李盛; 袁华; 江宏兵; 万林忠

    2016-01-01

    目的:探讨牙槽突裂髂骨块状骨植骨术的临床可行性和可靠性。方法回顾分析15例行“牙槽突裂髂骨块状骨植骨术”的恒牙列牙槽突裂患者,随访6个月以上,收集临床资料,并进行影像学分析。结果所有患者均能定期复诊,术后13例患者创口愈合良好,2例因创口裂开导致植骨失败。影像学资料显示术后6个月植骨区间隙消失,骨桥形成,且植骨区无明显吸收。已有2例患者完成正畸及种植治疗。术后3个月所有患者均可正常行走,无明显行动障碍。结论牙槽突裂髂骨块状骨植骨术短期临床效果满意,移植骨吸收少,长期效果还需进一步研究。%Objective To investigate the feasibility and reliability of alveolar bulk bone grafting in clinical practice. Methods 15 cases of alveolar cleft treated with alveolar bulk bone grafting were analyzed retrospectively, and were followed up for over 6 months. Clinical materials were collected to carry out the radiological analysis. Results The clinical over 6-month follow⁃up of 15 cases was finished. 13 patients showed satisfactory recovery of wounds. 2 cases failed due to the dehiscence. The radiological materials showed that after 6 months the bone graft clearances disappeared, bone bridge formed and bone graft area had no obvious absorption.2 patients fin⁃ished the orthodontic treatment and dental implantation. All the patients could walk normally after 3 months and had no obvious action barriers. Conclusions Alveolar bulk bone grafting, a new surgical approach for alveolar cleft, has satisfactory short⁃term clinical effects, and the long⁃term clinical effects need more further studies.

  5. Effectiveness of Lateral Bone Augmentation on the Alveolar Crest Dimension: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Sanz-Sánchez, I; Ortiz-Vigón, A; Sanz-Martín, I; Figuero, E; Sanz, M

    2015-09-01

    Lateral ridge augmentation procedures are aimed to reconstruct deficient alveolar ridges or to build up peri-implant dehiscence and fenestrations. The objective of this systematic review was to assess the efficacy of these interventions by analyzing data from 40 clinical studies evaluating bone augmentation through either the staged or the simultaneous approach. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guideline for systematic reviews was used. The primary outcomes were the changes at reentry, in the ridge width, and in the vertical and horizontal dimensions of the peri-implant defect, measured in millimeters, in the staged and simultaneous approaches, respectively. The results of the meta-analysis showed, for the simultaneous approach, a statistically significant defect height reduction when all treatments were analyzed together (weighted mean difference [WMD] = -4.28 mm; 95% confidence interval: [CI] -4.88, -3.69; P bone replacement grafts with barrier membranes was associated with superior outcomes The most frequently used intervention was the combination of xenograft and bioabsorbable membrane. Similarly, for the staged approach, there was a statistically significant horizontal gain when all treatment groups were combined (WMD = 3.90 mm; 95% CI: 3.52, 4.28; P bone blocks. Both treatment strategies led to high survival and success rates (>95%) for the implants placed on the regenerated sites. Nonexposed sites gained significantly more in the simultaneous and staged approaches (WMD = 1.1 and 3.1 mm).

  6. Generation and Identification of GM-CSF Derived Alveolar-like Macrophages and Dendritic Cells From Mouse Bone Marrow.

    Science.gov (United States)

    Dong, Yifei; Arif, Arif A; Poon, Grace F T; Hardman, Blair; Dosanjh, Manisha; Johnson, Pauline

    2016-06-25

    Macrophages and dendritic cells (DCs) are innate immune cells found in tissues and lymphoid organs that play a key role in the defense against pathogens. However, they are difficult to isolate in sufficient numbers to study them in detail, therefore, in vitro models have been developed. In vitro cultures of bone marrow-derived macrophages and dendritic cells are well-established and valuable methods for immunological studies. Here, a method for culturing and identifying both DCs and macrophages from a single culture of primary mouse bone marrow cells using the cytokine granulocyte macrophage colony-stimulating factor (GM-CSF) is described. This protocol is based on the established procedure first developed by Lutz et al. in 1999 for bone marrow-derived DCs. The culture is heterogeneous, and MHCII and fluoresceinated hyaluronan (FL-HA) are used to distinguish macrophages from immature and mature DCs. These GM-CSF derived macrophages provide a convenient source of in vitro derived macrophages that closely resemble alveolar macrophages in both phenotype and function.

  7. 糖尿病牙周炎模型大鼠的牙槽骨丧失%Alveolar bone loss in rat models of diabetic periodontitis

    Institute of Scientific and Technical Information of China (English)

    王立刚; 徐彬; 迪丽努尔•阿吉; 古丽努尔•阿吾提

    2015-01-01

      结果与结论:钢丝结扎后1,2,3,4周大鼠牙槽骨丧失程度:糖尿病牙周炎组>慢性牙周炎组>正常对照组(P OBJECTIVE:To establish rat models of diabetic periodontitis and chronic periodontitis, and to further clarify diabetes-increased degree of alveolar bone resorption in periodontitis rats METHODS:Fifty-two eight-week-old specific-pathogen-free male Sprague-Dawley rats were randomly divided into diabetic periodontitis group, chronic periodontitis group and normal control group. In the diabetic periodontitis group, rat models of diabetic periodontitis were established by injection of streptozotocin+periodontal ligation. In the chronic periodontitis group, rat models of chronic periodontitis were established by periodontal ligation and constant pressure. In the normal control group, rats were fed normal y. At 1, 2, 3 and 4 weeks after ligation, changes in periodontium of rats of each group were observed. The maxil a alveolar bone specimens were taken. The degree of alveolar bone loss value in rats of each group was observed under a stereomicroscope. RESULTS AND CONCLUSION:At 1, 2, 3 and 4 weeks after ligation with steel wire, the degree of rat alveolar bone loss was as fol ows:diabetic periodontitis group>chronic periodontitis group>normal control group (P<0.05). Results verified that animal models of diabetic periodontitis and chronic periodontitis were successful y established. Diabetes can increase the destruction to periodontal tissue with periodontitis, and increase alveolar bone loss.

  8. 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

  9. Bioprinting Organotypic Hydrogels with Improved Mesenchymal Stem Cell Remodeling and Mineralization Properties for Bone Tissue Engineering.

    Science.gov (United States)

    Duarte Campos, Daniela Filipa; Blaeser, Andreas; Buellesbach, Kate; Sen, Kshama Shree; Xun, Weiwei; Tillmann, Walter; Fischer, Horst

    2016-06-01

    3D-manufactured hydrogels with precise contours and biological adhesion motifs are interesting candidates in the regenerative medicine field for the culture and differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). 3D-bioprinting is a powerful technique to approach one step closer the native organization of cells. This study investigates the effect of the incorporation of collagen type I in 3D-bioprinted polysaccharide-based hydrogels to the modulation of cell morphology, osteogenic remodeling potential, and mineralization. By combining thermo-responsive agarose hydrogels with collagen type I, the mechanical stiffness and printing contours of printed constructs can be improved compared to pure collagen hydrogels which are typically used as standard materials for MSC osteogenic differentiation. The results presented here show that MSC not only survive the 3D-bioprinting process but also maintain the mesenchymal phenotype, as proved by live/dead staining and immunocytochemistry (vimentin positive, CD34 negative). Increased solids concentrations of collagen in the hydrogel blend induce changes in cell morphology, namely, by enhancing cell spreading, that ultimately contribute to enhanced and directed MSC osteogenic differentiation. 3D-bioprinted agarose-collagen hydrogels with high-collagen ratio are therefore feasible for MSC osteogenic differentiation, contrarily to low-collagen blends, as proved by two-photon microscopy, Alizarin Red staining, and real-time polymerase chain reaction.

  10. Influence of orthodontic tooth movement on alveolar bone morphology and bone mineral density%正畸牙移动对牙槽骨形态及骨密度的影响

    Institute of Scientific and Technical Information of China (English)

    张国华

    2015-01-01

    背景:在正畸治疗过程中部分患者出现了牙齿松动、牙槽骨形态异常情况,甚至在一定程度上牙周疾病的概率有所增加.目的:分析正畸牙移动对牙槽骨形态及骨密度的影响.方法:纳入62例正畸治疗患者,其中男34例,女28例,年龄18-30岁,正畸治疗6个月后,利用三维锥形束 CT 机扫描患者上、下颌骨前牙区、后牙区、中切牙牙槽区,以及两侧中切牙与侧切牙牙槽间隔的骨密度.结果与结论:正畸治疗 6 个月后,所有患者牙齿坚固,未见异常动度,牙龈颜色呈现健康的粉红色,质地坚韧而不活动,探诊时无出血情况.正畸治疗前,上颌不同牙槽间隔牙槽骨密度比较差异无显著性意义(P > 0.05),治疗6个月后比较差异也无显著性意义(P > 0.05),但同一牙槽间隔正畸治疗6个月后的骨密度低于治疗前(P 0.05). However, the bone mineral density in the same alveolar space was reduced significantly after 6 months of treatment (P < 0.05). The bone mineral density of the maxilary and mandibular alveolar bone was varied consistently. In addition, the bone mineral density of the maxilary alveolar bone was significantly higher than that of the mandibular alveolar bone both before and after orthodontic treatment (P < 0.05). These findings indicate that under orthodontic treatment, the bone mineral density of the maxilary alveolar bone may be higher than that of the mandibular alveolar bone, but there is no effect on orthodontic results as wel as the morphology and health of alveolar bone.

  11. Support Immersion Endoscopy in Post-Extraction Alveolar Bone Chambers: A New Window for Microscopic Bone Imaging In Vivo.

    Directory of Open Access Journals (Sweden)

    Wilfried Engelke

    Full Text Available Using an endoscopic approach, small intraoral bone chambers, which are routinely obtained during tooth extraction and implantation, provide visual in vivo access to internal bone structures. The aim of the present paper is to present a new method to quantify bone microstructure and vascularisation in vivo. Ten extraction sockets and 6 implant sites in 14 patients (6 men / 8 women were examined by support immersion endoscopy (SIE. After tooth extraction or implant site preparation, microscopic bone analysis (MBA was performed using short distance SIE video sequences of representative bone areas for off-line analysis with ImageJ. Quantitative assessment of the microstructure and vascularisation of the bone in dental extraction and implant sites in vivo was performed using ImageJ. MBA revealed bone morphology details such as unmineralised and mineralised areas, vascular canals and the presence of bleeding through vascular canals. Morphometric examination revealed that there was more unmineralised bone and less vascular canal area in the implant sites than in the extraction sockets.

  12. Low-dose hydrocortisone replacement therapy is associated with improved bone remodelling balance in hypopituitary male patients.

    Science.gov (United States)

    Behan, Lucy-Ann; Kelleher, Grainne; Hannon, Mark J; Brady, Jennifer J; Rogers, Bairbre; Tormey, William; Smith, D; Thompson, Christopher J; McKenna, Malachi J; Agha, Amar

    2014-01-01

    Glucocorticoid (GC) therapy is associated with adverse effects on bone metabolism, yet the effects of different GC physiological replacement regimens in hypopituitarism are not well characterised. We aimed to assess the effect of three hydrocortisone (HC) replacement dose regimens on bone turnover. An open cross-over study randomising ten hypopituitary men with severe acth deficiency to three commonly used HC dose regimens: dose A (20 mg mane and 10 mg tarde), dose B (10 mg mane and 10 mg tarde) and dose C (10 mg mane and 5 mg tarde). Following 6 weeks of each regimen, the participants underwent 24-h serum cortisol sampling and measurement of bone turnover markers: bone-specific alkaline phosphatase, procollagen type I N-propeptide (PINP), intact osteocalcin (OC(1-49)), C-terminal cross-linking telopeptide (CTX-I) and tartrate-resistant acid phosphatase 5b (TRACP5b). Bone remodelling balance was estimated as an absolute ratio (PINP:CTX-I) and as an index using standardised scores derived from the matched controls. There were significant increases in the concentrations of the formation markers PINP (P=0.045) and OC(1-49) (P=0.006) and in the PINP:CTX-I ratio (P=0.015), and a more positive bone remodelling balance index (P=0.03) was observed in patients on the lowest dose C than in those on the highest dose A. Mean 24-h cortisol concentrations correlated negatively with CTX-I (r=-0.66 and P=0.04) and TRACP5b (r=-0.74 and P=0.01) in patients on dose B and with OC(1-49) (r=-0.66 and P=0.04) and CTX-I (r=-0.81 and P<0.01) in patients on dose C. In patients receiving the lower-dose regimen, trough cortisol concentrations correlated with increased bone formation and resorption. Low-dose HC replacement (10 mg mane and 5 mg tarde) is associated with increased bone formation and a positive bone remodelling balance. This may have a long-term beneficial effect on bone health.

  13. [Secondary Alveolar Bone Grafting in Orofacial Cleft: A Survey of a Portuguese Tertiary Hospital].

    Science.gov (United States)

    Costa, Ana Isabel; Morgado, Hélder; Mariz, Carlos; Estevão-Costa, José Manuel

    2016-03-01

    Introdução: A fenda lábio-palatina é a malformação congénita craniofacial mais frequente. Na presença de defeito ósseo, a técnica de enxerto ósseo alveolar secundário é o método de correção mais consensual entre os autores. Neste estudo avalia-se o resultado da aplicação desta técnica num hospital terciário. Material e Métodos: Análise dos enxertos ósseos alveolares secundários realizados entre 2007 e 2014, sendo incluídos os casos em que a crista ilíaca foi a região dadora e em que a informação clínica e imagiológica estava completa. A eficácia da intervenção foi avaliada radiologicamente com recurso à escala de Bergland (tipo I-IV), e correlacionada com variáveis associadas à patologia e/ou correção cirúrgica. Resultados: Dos 32 enxertos ósseos alveolares secundários realizados, 29 cumpriam os critérios de inclusão: 13 casos (44,8%) correspondiam a fendas pré-forâmen unilaterais completas; quatro (13,8%) a fendas pré-forâmen bilaterais completas; oito (27,6%) a fendas transforâmen unilaterais e quatro (13,8%) a fendas transforâmen bilaterais. Pela escala de Bergland (aplicada com um seguimento médio de 8 ± 5 meses), seis eram do tipo I, 15 do tipo II, cinco de tipo III e três do tipo IV. Não foi encontrada associação entre a eficácia da intervenção cirúrgica e o tipo de fenda lábio-palatina, presença do incisivo e fase de erupção do canino. Cinco doentes foram submetidos a novo enxerto ósseo alveolar (três tipo II e dois tipo III na avaliação inicial). Discussão: Na presente série, o enxerto ósseo alveolar foi eficaz na maioria dos doentes (72%, tipo I e II), independentemente do tipo de fenda lábio-palatina. A proporção de falências (10,3%) e a necessidade ulterior de reintervenção (17%) foram relativamente altas justificando o seguimento a longo-prazo e a continuação deste estudo. Conclusão: Importa realçar o envolvimento multidisciplinar para identificação atempada do momento

  14. Changes in alveolar bone thickness due to retraction of lower anterior teeth%内收下切牙对下切牙区牙槽骨改建的影响

    Institute of Scientific and Technical Information of China (English)

    李佳岭; 李小兵; 李佳园

    2011-01-01

    目的 对拔除第一前磨牙内收下切牙后,下切牙区牙槽骨的改建情况进行头影测量分析。方法选择47例治疗前轻度拥挤、拔除4颗第一前磨牙以内收下切牙的患者,在其治疗前后行X线头颅侧位片检查,采用盲法对软硬组织和下切牙区牙槽唇舌侧厚度的进行测量,并采用SPSS 13.0软件对治疗前后的测量数据进行配对t检验。结果头影测量分析显示:拔除4颗第一前磨牙内收切牙后,下切牙区牙槽整体厚度减小。唇舌向:舌侧牙槽厚度减少较多,唇侧牙槽厚度减小较少。垂直向:靠近牙冠的牙槽厚度减少较少,根部减小较多。结论内收下切牙后,牙槽骨的生物学改建以吸收为主,增生很少,因此下前牙牙槽厚度减少明显。治疗前下齿槽座点和根尖处唇舌侧骨皮质改建能力较弱,可以近似作为下切牙移动的“限制点”所在,帮助临床医生确定下切牙移动的范围。%Objective To investigate the changes of alveolar bone thickness after retraction of lower incisor. Methods 47 patients of slight crowding and four first premolars extracted for orthodontics purpose, were collected as study samples. Their pre- and post treatment cephalometric films were analyzed by blind method for hard and soft tissue changes and remodeling of anterior alveolar after treatment. Paired t test was used to evaluate the hard and soft tissue changes with SPSS 13.0 software package. Results The cephalometric values demonstrated that: Lower incisor alveolar thickness showed a significant decrease after incisor retraction. From sagittal view, the lingual cortical plate thickness reduced more than the labial one; from vertical view, alveolar bone thickness at the apical level decreased more than that at the coronal level. Conclusion The absorption of alveolar bone exceed the apposition during lower incisor retraction, so that the alveolar thickness decreased significantly

  15. 雌激素对正畸骨改建相关细胞因子的影响%Effects of estrogen on cytokines related to bone remodeling in orthodontic treatment

    Institute of Scientific and Technical Information of China (English)

    朱倩; 蔡萍

    2014-01-01

    Decreased bone density and osteoporosis are not favorable to orthodontic treatment. Estrogen can promote alveolar bone formation and inhibit bone resorption. Estrogen regulates bone remodeling through various cytokines under orthodontic force. First, estrogen can inhibit bone resorption and promote bone restoration by upregulating the expression of osteoprotegerin and downregulating the receptor activator of nuclear factor-κB ligand. Second, estrogen can promote osteoblasts and osteocytes to secrete bone morphogenetic proteins, which accelerate alveolar bone remodeling. In addition, estrogen can control alveolar bone resorptionby significantly inhibiting tumor necrosis factor-α, interleukin-1, and interleukin-6. Estrogen can also inhibit bone resorption by suppressing the expression of interferon-γ. Estrogen deficiency caninduce osteoclastogenesis by increasing the expression of macrophage colony-stimulating factor. Therefore, administration of optimum dosagesof estrogen is necessary in patients with osteoporosis for effective and safe orthodontic treatments.%骨密度降低和骨质疏松不利于正畸治疗的进行,而雌激素可促进牙槽骨形成,抑制骨吸收。在正畸矫治力作用下,多种细胞因子参与雌激素对正畸骨的改建。首先,雌激素可以通过上调骨保护蛋白和下调核因子-κB受体活化因子配体的表达来抑制骨吸收,促进骨形成;其次,雌激素也可以通过促进成骨细胞和骨细胞分泌骨形态发生蛋白来加快牙槽骨的改建;另外,雌激素可以抑制肿瘤坏死因子α,白细胞介素-1和白细胞介素-6的表达,从而控制骨吸收;雌激素缺乏使巨噬细胞集落刺激因子基因的表达增加从而促进破骨细胞的形成,相反,雌激素可以通过抑制干扰素-γ的表达来抑制骨吸收。由此可见,对于某些骨质疏松患者,为达到有效安全的正畸治疗目的,补充适当剂量的雌激素不失为一种可靠的辅助治疗方法。

  16. Posttraumatic Displacement Management: Lateral Luxation and Alveolar Bone Fracture in Young Permanent Teeth with 5 Years of Follow-Up

    Directory of Open Access Journals (Sweden)

    Heitor Marques Honório

    2015-01-01

    Full Text Available Dental trauma is an important public health problem due to high prevalence and associated limitations. The external impact accounting for trauma may result in different injury types to teeth and supporting structures. This paper describes a clinical case of tooth trauma in an 8-year-old patient exhibiting the displacement of three permanent teeth with open root apexes. Although the traumatic impact resulted in two injury types to teeth and supporting tissues (lateral luxation and alveolar bone fracture, the therapeutic approach was the same in both situations. The bone and teeth were repositioned by digital pressure, stabilized by semirigid splint, and followed up at every week. After six weeks, the splint was removed. At that moment, the clinical and radiographic findings indicated normal soft/hard tissues and absence of pulp/periodontal pathologies. At the fifth year of follow-up, the treatment success of the case was confirmed, although it has been observed that all lower incisors exhibited pulp obliteration as a consequence of the dental trauma.

  17. The Importance of Immediate Bone Block Autograft to Successfully Restore the Function and Aesthetic of the Anterior Alveolar Process and Teeth.

    Science.gov (United States)

    Singer, Lawrence David

    2015-12-01

    Maxillofacial traumatic injuries can damage the jaw, teeth, and soft tissues of the head and neck region. When these injuries occur, best practice is to reconstruct as comprehensively as is clinically prudent at time of injury. Smart and efficient procedures during the initial surgery can minimize subsequent reconstructive procedures in scope and number, minimize expense, and result in a better final aesthetic and functional outcome. Restoration of anterior alveolar jaw fractures with comminuted or avulsed segments becomes a complex prospect when left untreated after initial trauma or injury and can result in alveolar ridge defects that are difficult, costly, and cumbersome to repair. This case report details one 19-year-old woman who had a traumatic injury in these areas and has a best result outcome because of immediate reconstruction efforts involving a bone block autograft to preserve alveolar process anatomy.

  18. Technique to assess the alveolar bone width for immediate implant placement in fresh extraction sockets

    Directory of Open Access Journals (Sweden)

    Neeraj Kumar Chandraker

    2013-01-01

    Conclusion: This technique will help the surgeon understand the thickness of labial plate especially the apical region without reflecting the flap, also aid in selection of proper dimension of dental implant, and if bone graft is needed.

  19. Impaired differentiation of macrophage lineage cells attenuates bone remodeling and inflammatory angiogenesis in Ndrg1 deficient mice.

    Science.gov (United States)

    Watari, Kosuke; Shibata, Tomohiro; Nabeshima, Hiroshi; Shinoda, Ai; Fukunaga, Yuichi; Kawahara, Akihiko; Karasuyama, Kazuyuki; Fukushi, Jun-Ichi; Iwamoto, Yukihide; Kuwano, Michihiko; Ono, Mayumi

    2016-01-18

    N-myc downstream regulated gene 1 (NDRG1) is a responsible gene for a hereditary motor and sensory neuropathy-Lom (Charcot-Marie-Tooth disease type 4D). This is the first study aiming to assess the contribution of NDRG1 to differentiation of macrophage lineage cells, which has important implications for bone remodeling and inflammatory angiogenesis. Ndrg1 knockout (KO) mice exhibited abnormal curvature of the spine, high trabecular bone mass, and reduced number of osteoclasts. We observed that serum levels of macrophage colony-stimulating factor (M-CSF) and macrophage-related cytokines were markedly decreased in KO mice. Differentiation of bone marrow (BM) cells into osteoclasts, M1/M2-type macrophages and dendritic cells was all impaired. Furthermore, KO mice also showed reduced tumor growth and angiogenesis by cancer cells, accompanied by decreased infiltration of tumor-associated macrophages. The transfer of BM-derived macrophages from KO mice into BM-eradicated wild type (WT) mice induced much less tumor angiogenesis than observed in WT mice. Angiogenesis in corneas in response to inflammatory stimuli was also suppressed with decreased infiltration of macrophages. Taken together, these results indicate that NDRG1 deficiency attenuates the differentiation of macrophage lineage cells, suppressing bone remodeling and inflammatory angiogenesis. This study strongly suggests the crucial role of NDRG1 in differentiation process for macrophages.

  20. Relationship between alveolar cleft bone grafting and facial skeletal growth%牙槽突裂植骨与颌骨生长发育的关系

    Institute of Scientific and Technical Information of China (English)

    韶青华; 陈振琦

    2013-01-01

      牙槽突裂植骨是唇腭裂患者序列治疗的重要组成部分。学者们在植骨时机的选择上存在分歧,主要分为一期植骨和二期植骨,原因在于不同时期植骨对颌骨生长发育的影响不同。本文分别从这两个植骨时机上阐述了其植骨来源以及植骨与颌骨生长发育的关系。%Bone grafting of alveolar cleft is an essential step in the sequential management of patients with clefts of lip, alveolus and palate. There is little agreement on the optimal time, which includes primary bone grafting and secondary bone grafting. This is caused by the effects of alveolar bone grafting in different times on facial skeletal growth. This article described the sources of bone graft as well as the relationship between bone grafting and facial skeletal growth from the two bone graft timing.

  1. Kinetics of gene expression and bone remodelling in the clinical phase of collagen induced arthritis

    DEFF Research Database (Denmark)

    Denninger, Katja Caroline Marie; Litman, Thomas; Marstrand, Troels

    2015-01-01

    Introduction: Pathological bone changes differ considerably between inflammatory arthritic diseases and most studies have focused on bone erosion. Collagen-induced arthritis (CIA) is a model for rheumatoid arthritis, which, in addition to bone erosion, demonstrates bone formation at the time...... osteoblast differentiation and function, which mirrored the histopathological bone changes. The differentially expressed genes belong to the bone morphogenetic pathway (BMP) and, in addition, include the osteoblast markers integrin-binding sialoprotein (Ibsp), bone gamma-carboxyglutamate protein (Bglap1...

  2. 伴唇侧牙槽骨缺损的临床修复分析%Clinical repair analysis on alveolar bone defect on labial side

    Institute of Scientific and Technical Information of China (English)

    沈晴

    2014-01-01

    目的:探讨伴唇侧牙槽骨缺损的临床修复方法与效果。方法选择伴唇侧牙槽骨缺损患者50例,采用诱导活性材料进行修复治疗。结果所有患者完成手术,成功率为100.0%。与术前比较,患者植骨材料充填牙槽突缺损的间隙无明显移位,对比差异明显(P<0.05)。结论采用骨诱导活性材料修复伴唇侧牙槽骨缺损能取得很好的临床效果,值得推广应用。%Object: To analysis the strategy and effect of clinical repair on alveolar bone defect on labial side. Methods: 50 cases with alveolar bone defect on labial side were given prosthodontic treatment using induction active material. Results: All the patients underwent the operation successfully and success rate was 100%. Compared with before operation, clearance of alveolar process defect was filled by bone substitute material without obvious displacement, the difference was significant (P<0.05). Conclusion: Using bone substitute material to repair alveolar bone defect on labial side obtained good clinical effect, and worthy of being widely applied in clinic.

  3. A comparative study of bone remodeling molecules expression in different types of jaw ameloblastoma.

    Science.gov (United States)

    Iakovou, Maria; Chrysomali, Evanthia; Piperi, Evangelia; Fanourakis, Galinos; Sklavounou, Alexandra; Vlachodimitropoulos, Dimitrios; Tseleni-Balafouta, Sophia

    2015-08-01

    Solid ameloblastoma demonstrates a more invasive behavior compared to unicystic. The follicular ameloblastoma is referred that may present a higher recurrence potential compared to the plexiform variant. In this study, the different ameloblastoma clinical types and histopathological variants were examined regarding the expression of bone remodeling-related molecules OPG, RANKL, and TRAIL. Immunostained sections of 29 solid and 11 unicystic ameloblastoma cases were semi-quantitatively evaluated and analyzed using Mann-Whitney or Kruskal-Wallis tests. Solid ameloblastoma showed a significantly increased OPG expression (P = 0.004) associated with the follicular (P ameloblastoma for differences by the histopathological pattern (no RANKL expression when plexiform pattern was seen compared to follicular). Comparison between the clinical types showed differences regarding the ratio of OPG/RANKL and TRAIL/RANKL expression. Higher OPG expression over RANKL was observed in 86.2% of the solid compared to 36.4% of the unicystic type. There was no difference in the ratio of TRAIL/RANKL expression in the unicystic, whereas 55.2% of the solid ameloblastomas showed a greater TRAIL expression over RANKL. Our results suggest OPG overexpression and RANKL underexpression in solid ameloblastoma; this may reflect a possible prevalence of the OPG/TRAIL over the OPG/RANKL signaling pathway, resulting in inactivation of TRAIL-induced apoptosis in ameloblastic cells. In unicystic ameloblastoma, the RANKL/OPG expression immunoprofile among histological variants is compatible with the reported biologic behavior. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Effects of Gastric Bypass and Gastric Banding on Bone Remodeling in Obese Patients with Type 2 Diabetes

    DEFF Research Database (Denmark)

    Yu, Elaine W; Wewalka, Marlene; Ding, Su-Ann;

    2016-01-01

    CONTEXT: Roux-en-Y gastric bypass (RYGB) leads to high-turnover bone loss, but little is known about skeletal effects of laparoscopic adjustable gastric banding (LAGB) or mechanisms underlying bone loss after bariatric surgery. OBJECTIVE: To evaluate effects of RYGB and LAGB on fasting...... and postprandial indices of bone remodeling. DESIGN AND SETTING: Ancillary investigation of a prospective study at 2 academic institutions. PARTICIPANTS: Obese adults aged 21-65 years with type 2 diabetes who underwent RYGB (n=11) or LAGB (n=8). OUTCOMES: Serum C-terminal telopeptide (CTX), procollagen type 1 (P1......NP), and parathyroid hormone (PTH) were measured during a mixed meal tolerance test at baseline, 10 days and 1 year after surgery. Changes in 25-hydroxyvitamin D, polypeptide YY (PYY), glucagon-like peptide-1, glucose-dependent insulinotropic peptide, and insulin were also assessed. RESULTS: Fasting...

  5. Graphene oxide scaffold accelerates cellular proliferative response and alveolar bone healing of tooth extraction socket.

    Science.gov (United States)

    Nishida, Erika; Miyaji, Hirofumi; Kato, Akihito; Takita, Hiroko; Iwanaga, Toshihiko; Momose, Takehito; Ogawa, Kosuke; Murakami, Shusuke; Sugaya, Tsutomu; Kawanami, Masamitsu

    2016-01-01

    Graphene oxide (GO) consisting of a carbon monolayer has been widely investigated for tissue engineering platforms because of its unique properties. For this study, we fabricated a GO-applied scaffold and assessed the cellular and tissue behaviors in the scaffold. A preclinical test was conducted to ascertain whether the GO scaffold promoted bone induction in dog tooth extraction sockets. For this study, GO scaffolds were prepared by coating the surface of a collagen sponge scaffold with 0.1 and 1 µg/mL GO dispersion. Scaffolds were characterized using scanning electron microscopy (SEM), physical testing, cell seeding, and rat subcutaneous implant testing. Then a GO scaffold was implanted into a dog tooth extraction socket. Histological observations were made at 2 weeks postsurgery. SEM observations show that GO attached to the surface of collagen scaffold struts. The GO scaffold exhibited an interconnected structure resembling that of control subjects. GO application improved the physical strength, enzyme resistance, and adsorption of calcium and proteins.