Home About us Contact
|
Home About us Contact | ||
|
|
||
Compressive Forces (compressive + force)
Selected AbstractsCOATING CHARACTERISTICS OF FRIED CHICKEN BREASTS PREPARED WITH DIFFERENT PARTICLE SIZE BREADINGJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2002MOHAMAD YUSOF MASKAT Characteristics of coatings formed from breading of different particle sizes were investigated in breaded, fried chicken breasts. Breading was divided into three categories namely, small (particle size , U.S. No. 60 mesh), medium (particle size between U.S. No. 20 and U.S. No. 60 mesh) and large (particle size > U.S. No. 20 mesh). Chicken breasts were battered, breaded and deep-fat fried for 240 s at 160C. Smaller breading particle size produced smoother and more uniform coatings. Compressive force at 80% strain was 14.3, 85.6 and 130.5 N for small medium and large particle size breading, respectively. With larger breading particle size, L* and a* color values increased, while b* values showed no significant change. Acoustical data taken during compression of coatings did not show any significant differences due to different breading particle sizes. [source] Aging stimulates cyclooxygenase-2 expression and prostaglandin E2 production in human periodontal ligament cells after the application of compressive forceJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2007Kotoe Mayahara Background and Objectives:, Some clinical studies show that alveolar crestal bone loss is higher in adults than in young patients during orthodontic treatment, but the causes of such a phenomenon have not been elucidated. It is known that prostaglandin E2 (PGE2) is a proinflammatory agent and one of the potent osteoclast-inducing factors, and is produced by human periodontal ligament cells in response to orthodontic force. The aim of this study was to investigate age-related change in the biosynthetic capacity of PGE2 and its regulatory gene, cyclooxygenase 2 (COX-2) from periodontal ligament cells in response to mechanical stress. Methods:, Compressive force of 2 g/cm2 was applied for 3,48 h to periodontal ligament cells obtained from human donors aged 9,50 years, and COX-2 mRNA expression in and PGE2 production by the periodontal ligament cells in response to the compressive force were examined. Results:, Application of a compressive force of 2 g/cm2 for 3,48 h significantly stimulated these factors in both time- and age-dependent manners. Furthermore, these increases were dramatically larger in periodontal ligament cells obtained from donors over the age of 35. Conclusions:, Periodontal ligament cells obtained from old donors have significantly greater COX-2 expression and PGE2 production in response to compressive force than those from younger donors. The turning point of aging, where significantly larger amounts of theses factors begin production, appears to be around the age of 35. These results may be positively related to the acceleration of alveolar crestal bone loss during orthodontic treatment in adult patients. [source] A biomechanical study on flexible intramedullary nails used to treat pediatric femoral fracturesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2005Jason K. Green Abstract Flexible intramedullary nails have been indicated to treat femoral fractures in pediatric patients. The purpose of this study was to examine the stability of simulated transverse fractures after retrograde intramedullary flexible nail fixation. Various nail diameter combinations were tested using composite femurs in bending, torsion, and a combined axial/bending test where a vertical compressive force was applied to the femoral head. The cross-sectional percent area fill of the nails within the femurs was also determined. In 4 point bending, the greatest repair stiffness was 12% of the intact stiffness. In torsion, the greatest stiffness was 1% of the intact stiffness for either internal or external rotation. The greatest repair stiffness was 80% of the intact stiffness for a compressive load applied to the femoral head. Nail combinations with single nail diameters greater than 40% of the mid-shaft canal width, as measured from an AP radiograph, prevented the fracture from being reduced and left a posterior gap. Flexible intramedullary nails may be of value in the treatment of pediatric femoral fractures, but care must be taken to insert nails that are correctly sized for the canal and to protect the healing fracture from high torsional and bending loads. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Aging stimulates cyclooxygenase-2 expression and prostaglandin E2 production in human periodontal ligament cells after the application of compressive forceJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2007Kotoe Mayahara Background and Objectives:, Some clinical studies show that alveolar crestal bone loss is higher in adults than in young patients during orthodontic treatment, but the causes of such a phenomenon have not been elucidated. It is known that prostaglandin E2 (PGE2) is a proinflammatory agent and one of the potent osteoclast-inducing factors, and is produced by human periodontal ligament cells in response to orthodontic force. The aim of this study was to investigate age-related change in the biosynthetic capacity of PGE2 and its regulatory gene, cyclooxygenase 2 (COX-2) from periodontal ligament cells in response to mechanical stress. Methods:, Compressive force of 2 g/cm2 was applied for 3,48 h to periodontal ligament cells obtained from human donors aged 9,50 years, and COX-2 mRNA expression in and PGE2 production by the periodontal ligament cells in response to the compressive force were examined. Results:, Application of a compressive force of 2 g/cm2 for 3,48 h significantly stimulated these factors in both time- and age-dependent manners. Furthermore, these increases were dramatically larger in periodontal ligament cells obtained from donors over the age of 35. Conclusions:, Periodontal ligament cells obtained from old donors have significantly greater COX-2 expression and PGE2 production in response to compressive force than those from younger donors. The turning point of aging, where significantly larger amounts of theses factors begin production, appears to be around the age of 35. These results may be positively related to the acceleration of alveolar crestal bone loss during orthodontic treatment in adult patients. [source] Distribution pattern of versican, link protein and hyaluronic acid in the rat jreiodontal ligament during exjreimental tooth movementJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2002R. Sato The ability of the jreiodontal ligament (PDL) to rapidly remodel is the basis of orthodontic tooth movement. During the tooth movement, matrix proteoglycans (PGs) may play important roles in spatial, mechanical and biological aspects for the maintenance and repair of the PDL. The aim of this study was to characterize the distribution of a large hyaluronic acid (HA)-binding proteoglycan, versican, link protein (LP) and HA in the rat molar PDL during exjreimental tooth movement by histochemical and immunohistochemical methods. Exjreimental tooth movement was jreformed according to Waldo's method. Histologically, regressive changes, such as decrease of fibroblasts and collagen fibers and exudative change of edema were observed in the compressive side and progressive changes, such as proliferation of fibroblasts and collagen fibers, in the strain side one day after treatment. By 3 days after tooth movement, regressive or progressive changes were not observed in either side. Using monoclonal antibodies specific to versican core protein or LP, the positive immunoreactivity for both molecules was constantly observed throughout the PDL. After the exjreimental force was applied to the tooth, however, the immunostainings of versican and LP became significantly intense only in the compressive side but decreased in the strain side. The intensity in the compressive side was strongest one day after the force was applied and gradually diminished thereafter. HA of both sides did not change during exjreimental tooth movement. Since HA is present in the PDL, large amounts of versican and LP expressed in the compressive side may create large hydrated aggregates via their association with HA that dissipates the compressive force applied to this tissue. [source] Hydrodynamics of gas,solid fluidization in tapered bedsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009J. S. N. Murthy Abstract Gas,solid fluidization has a wide range of industrial applications like catalytic reactions, combustion, gasification, etc. In a number of these applications, there is particle size reduction during the operation leading to severe entrainment and limitation of operating velocity. The various problems associated with particles of different sizes or changing particles sizes could be overcome by adopting tapered beds in fluidization operation. In the present investigation, the fluidization phenomenon in tapered beds has been critically assessed through experimental investigations using particles of different sizes and materials and wide range of apex angles of the vessels. The effect of particle size and apex angle on the fluidization behaviour is clearly brought out which has not been reported so far in literature. The importance of compressive force existing in tapered beds is highlighted. In addition, correlations for all hydrodynamic characteristics, viz. critical fluidization velocity, minimum velocity for full fluidization, maximum velocity for defluidization, peak pressure drop, fluctuation ratio, compressive force, and hysteresis have been developed some of which are proposed for the first time. La fluidisation gaz-solide revêt un vaste éventail d'applications industrielles comme les réactions catalytiques, la combustion, la gazéification, etc. Pour un certain nombre deces applications, il y a une réduction granulométrique durant l'activité menant à un entraînement età une limitation intenses de la vitesse de fonctionnement. Les divers problèmes liés aux particules de dimensions différentes ou aux dimensions de particules changeantes pourraient être surmontésen adoptant les lits coniques dans les activités de fluidisation. Dans le cadre de la présente étude, lephénomène de fluidisation dans les lits coniques a été évalué de façon critique au moyen devérifications expérimentales employant des particules de dimensions et de matières différentes et d'un vaste éventail d'angles de sommet de fluidiseurs. L'effet de la dimension des particules et del'angle des sommets sur le comportement de la fluidisation est nettement mis en évidence, ce quin'a pas été soulevé à venir jusqu'ici dans la documentation. L'importance de la force decompression qui existe dans les lits coniques est mise en évidence. De plus, les corrélations relativement à l'ensemble des caractéristiques hydrodynamiques, c.-à-d. la vitesse de fluidisation critique, la vitesse minimale de fluidisation complète, la vitesse maximale de défluidisation, la chute des pics de pression, le taux de fluctuation, la force de compression et l'hystérésis, ont été élaborées, certaines d'entre elles étant avancées pour la première fois. [source] Shaking table tests on seismic response of steel braced frames with column upliftEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 14 2006Mitsumasa Midorikawa Abstract Previous studies have suggested that rocking vibration accompanied by uplift motion might reduce the seismic damage to buildings subjected to severe earthquake motions. This paper reports on the use of shaking table tests and numerical analyses to evaluate and compare the seismic response of base-plate-yielding rocking systems with columns allowed to uplift with that of fixed-base systems. The study is performed using half-scale three-storey, 1 × 2 bay braced steel frames with a total height of 5.3 m. Base plates that yield due to column tension were installed at the base of each column. Two types of base plates with different thicknesses are investigated. The earthquake ground motion used for the tests and analyses is the record of the 1940 El Centro NS component with the time scale shortened by a factor of 1/,2. The maximum input acceleration is scaled to examine the structural response at various earthquake intensities. The column base shears in the rocking frames with column uplift are reduced by up to 52% as compared to the fixed-base frames. Conversely, the maximum roof displacements of the fixed and rocking frames are about the same. It is also noted that the effect of the vertical impact on the column associated with touchdown of the base plate is small because the difference in tensile and compressive forces is primarily due to the self-limiting tensile force in the column caused by yielding of the base plate. Copyright © 2006 John Wiley & Sons, Ltd. [source] Reliability-based preform shape design in forgingINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2005Jalaja Repalle Abstract A reliability-based optimization method is developed for preform shape design in forging. Forging is a plastic deformation process that transforms a simple shape of workpiece into a predetermined complex shape through a number of intermediate shapes by the application of compressive forces. Traditionally, these intermediate shapes are designed in a deterministic manufacturing domain. In reality, there exist various uncertainties in the forging environment, such as variations in process conditions, billet/die temperatures, and material properties. Randomness in these parameters could lead to variations in product quality and often induce heavy manufacturing losses. In this research, a robust preform design methodology is developed in which various randomnesses in parameters are quantified and incorporated through reliability analysis and uncertainty quantification techniques. The stochastic response surface approach is used to reduce computation time by establishing a relationship between the process performance and shape and random parameters. Finally, reliability-based optimization is utilized for preform shape design of an engine component to improve the product quality and robustness. Copyright © 2005 John Wiley & Sons, Ltd. [source] Periodontal repair in dogs: space-providing ePTFE devices increase rhBMP-2/ACS-induced bone formationJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2003Ulf M.E. Wikesjö Abstract Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) technologies have been shown to enhance alveolar bone formation significantly. Biomaterial (carrier) limitations, however, have restricted their biologic potential for indications where compressive forces may limit the volume of bone formed. The objective of this proof-of-principle study was to evaluate the potential of a space-providing, macroporous ePTFE device to define rhBMP-2-induced alveolar bone formation using a discriminating onlay defect model. Methods: Routine, critical size, 5,6 mm, supra-alveolar, periodontal defects were created around the third and fourth mandibular premolar teeth in four young adult Hound Labrador mongrel dogs. All jaw quadrants received rhBMP-2 (0.4 mg) in an absorbable collagen sponge (ACS) carrier. Contralateral jaw quadrants in subsequent animals were randomly assigned to receive additionally the dome-shaped, macroporous ePTFE device over the rhBMP-2/ACS implant or no additional treatment. The gingival flaps were advanced to cover the ePTFE device and teeth, and sutured. Animals were scheduled for euthanasia to provide for histologic observations of healing at 8 weeks postsurgery. Results: Healing was uneventful without device exposures. New bone formation averaged (±SD) 4.7±0.2 mm (98%) and 4.5±0.4 mm (94%) of the defect height, respectively, for jaw quadrants receiving rhBMP-2/ACS with the ePTFE device or rhBMP-2/ACS alone (p>0.05). In contrast, the regenerated bone area was significantly enhanced in jaw quadrants receiving rhBMP-2/ACS with the ePTFE device compared to rhBMP-2/ACS alone (9.3±2.7 versus 5.1±1.1 mm2; p<0.05). Cementum formation was similar for both treatment groups. Ankylosis compromised periodontal regeneration in all sites. Conclusions: The results suggest that the novel space-providing, macroporous ePTFE device appears suitable as a template to define rhBMP-2/ACS-induced alveolar bone formation. Zusammenfassung Hintergrund: Es wurde gezeigt, dass das rekombinante menschliche knochenmorphogenetische Protein 2 (rhBMP-2) die alveoläre Knochenbildung signifikant erhöht. Limitationen des Biomaterials (Träger) haben jedoch die biologischen Potenzen des Materials für die Indikationen, wo komprimierende Kräfte das Volumen des zu bildenden Knochen limitierten, eingeengt. Das Ziel dieser prinzipiellen geprüften Studie war die Evaluation der Platzhalterfunktion einer makroporösen e-PTFE Membran, um die von rhBMP-2 induzierten Knochenbildung unter Nutzung eines differenzierenden Onlaydefektmodells zu definieren. Methoden: Routinemäßig wurden supraalveoläre parodontale Defekte mit der kritischen Größe von 5,6 mm um die dritten und vierten Prämolaren bei 4 jungen adulten Labrodormischhunden geschaffen. Alle Quadranten erhielten rhBMP-2 (0.4 mg) in einem resorbierbaren Kollagenschwamm (ACS). Kontralaterale Quadranten bei den aufeinander folgenden Tieren wurden zufällig ausgewählt, um zusätzlich eine domförmige makroporöse e-PTFE Membran über das rhBMP-2/ACS Implantat oder keine zusätzliche Therapie zu erhalten. Die gingivalen Lappen wurden so präpariert, dass sie die e-PTFE Membran und Zähne bedeckten und vernäht. Die Tiere wurden 8 Wochen nach der Operation getötet und für histologische Untersuchungen vorbereitet. Ergebnisse: Die Heilung war komplikationslos ohne Exposition der Membran. Die neue Knochenbildung betrug durchschnittlich (±SD) 4.7±0.2 mm (98%) und 4.5±0.4 mm (94%) der Defekthöhe für die Quadranten, die rhBMP-2/ACS mit der e-PTFE Membran erhielten oder rhBMP-2/ACS allein (p>0,05). Im Kontrast dazu war das regenerierte Knochenfeld signifikant erweitert bei den Kieferquadranten, die rhBMP-2/ACS mit e-PTFE Membran erhielten im Vergleich zu denjenigen mit rhBMP-2/ACS allein (9.3±2.7 vs. 5.1±1.1 mm2; p<0.05). Die Zementbildung war in beiden Behandlungsgruppen ähnlich. Ankylosen gefährdeten die parodontalen Regeneration in allen Flächen. Schlussfolgerungen: Die Ergebnisse zeigen, dass die neue makroporöse Platzhalter e-PTFE Membran als Schablone nützlich ist, um die rhBMP-2/ACS induzierte alveoläre Knochenbildung zu betonen. Résumé Contexte: Des technologies utilisant la protéine-2 osseuse morphogénétique humaine recombinée (rhBMP-2) ont montré qu'elle permettait d'augmenter significativement la formation d'os alvéolaire. Les limites du biomatériel (vecteur), cependant, ont restreint leur potentiel biologique aux indications pour lesquels des forces compressives pourraient limiter le volume d'os en formation. L'objectif de cette étude fut d'évaluer le potentiel d'un dispositif en ePTFE macro-poreux permettant de créer un espace pour définir la formation d'os alvéolaire induit par la rhBMP-2 en utilisant un modèle discriminatoire de lésion. Méthodes: Des lésions parodontales supra-alvéolaires de taille critique, 5,6 mm, furent créées autour des troisièmes et quatrièmes prémolaires chez 4 Labrador adultes. Chaque quadrant a été traité par des éponges de collagène résorbables utilisé comme vecteur (ASC) contenant rhBMP-2 (0.4 mg). Les quadrants contralatéraux des animaux furent aléatoirement distribués pour recevoir (ou pas) en plus un dispositif macro-poreux en ePTFE, en forme de dôme sur les implants de rhBMP-2/ACS. Les lambeaux furent déplacés pour recouvrir le dispositif en ePTFE et les dents et suturés. Les animaux furent sacrifiés après 8 semaines pour fournir des observations histologiques de la cicatrisation. Résultats: La cicatrisation ne posait pas de problèmes et on ne nota pas d'exposition des dispositifs. La moyenne de la formation osseuse était de (±SD) 4.7±0.2 mm (98%) et 4.5±0.4 mm (94%) de la hauteur de la lésion, respectivement, pour les quadrants ayant été traités par la rhBMP-2/ACS avec le dispositif en ePTFE ou la rhBMP-2/ACS seule (p>0.05). A l'inverse, la surface osseuse régénérée était significativement plus importante dans les quadrants traités par la rhBMP-2/ACS et les dispositifs en ePTFE par rapport au site traités seulement par la rhBMP-2/ACS (9.3±2.7 vs. 5.1±1.1 mm2; p<0.05). La formation cémentaire était similaire pour les deux groupes de traitement. L'ankylose compromettait la régénération parodontale dans tous les sites. Conclusions: Ces résultats suggèrent que le dispositif en ePTFE macro-poreux, qui assure un espace, semble convenir comme standard pour définir la formation osseuse induite par la rhBMP-2/ACS. [source] Differential correlates of diet and phylogeny on the shape of the premaxilla and anterior tooth in sparid fishes (Perciformes: Sparidae)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2004M. Linde Abstract We explore the correlational patterns of diet and phylogeny on the shape of the premaxilla and anterior tooth in sparid fishes (Perciformes: Sparidae) from the western Mediterranean Sea. The premaxilla is less variable, and in spite of the presence of species-specific features, a common structural pattern is easily recognizable in all species (i.e. the ascending and the articular processes are fused in a single branch, as in many percoid fishes). In contrast, tooth shape is more variable, and different structural types can be recognized (e.g. canine-like or incisive). Coupling geometric morphometric and comparative methods we found that the relationship between shape, diet and phylogeny also differs between premaxilla and tooth. Thus, the shape of the premaxilla is significantly correlated with food type, whereas the shape of the teeth is not correlated with diet, and probably reflects the species phylogenetic relationships. Two biological roles, resistance against compressive forces generated in the buccal cavity and the size of the oral gape, would explain the ecomorphological patterns of the premaxilla. The premaxilla and anterior tooth appear to evolve at different rates (mosaic evolution) and represent an example of morphological traits belonging to the same functional unit but following uncoupled evolutionary pathways. [source] Skeletal tissue engineering using silk biomaterialsJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 2-3 2008Ana C. MacIntosh Abstract Silks have been proposed as potential scaffold materials for tissue engineering, mainly because of their physical properties. They are stable at physiological temperatures, flexible and resist tensile and compressive forces. Bombyx mori (silkworm) cocoon silk has been used as a suture material for over a century, and has proved to be biocompatible once the immunogenic sericin coating is removed. Spider silks have a similar structure to silkworm silk but do not have a sericin coating. This paper provides a general overview on the use of silk protein in biomaterials, with a focus on skeletal tissue engineering. Copyright © 2008 John Wiley & Sons, Ltd. [source] Structure and properties of multi-walled carbon nanotubes/polyethylene nanocomposites synthesized by in situ polymerization with supported Cp2ZrCl2 catalystPOLYMER COMPOSITES, Issue 3 2010Shiyun Li Multi-walled carbon nanotubes (MWCNTs)/polyethylene (PE) nanocomposites were prepared via in situ polymerization with MWCNTs supported Bis- (cyclopentadienyl) zirconium dichloride (Cp2ZrCl2) catalyst. X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscope (FESEM) results implied that Cp2ZrCl2 catalyst was immobilized in the surface of the MWCNTs supports via a bridge of methylaluminoxane (MAO). The efficient dispersion of MWCNTs in PE matrix and the strong compressive forces associated with PE on the MWCNTs were demonstrated by means of transmission electron microscope (TEM), FESEM and Raman spectra. With introducing 0.2 wt% MWCNTs, both the tensile strength and elongation of MWCNTs/PE nanocomposite were improved by factors of 1.6 (from 29 to 45 MPa) and 1.5 (from 909% to 1360%) comparing with the pure PE, respectively. Morphology observation of fractured surface revealed that the PE firmly adhered to the nanotubes, which was responsible for the significant improvement of the mechanical properties of nanocomposites. Thermal stabilities of the nanocomposites were significantly improved. In addition, the MWCNTs/PE nanocomposites showed very high ultraviolet (UV) shielding property, which could increase photooxidative stability of the PE. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source] Salient features in the locomotion of proboscideans revealed via the differential scaling of limb long bonesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010VALERY B. KOKSHENEV The standard differential scaling of proportions in limb long bones (length against circumference) was applied to a phylogenetically wide sample of the Proboscidea, Elephantidae and the Asian (Elephas maximus) and African (Loxodonta africana) elephants. In order to investigate allometric patterns in proboscideans and terrestrial mammals with parasagittal limb kinematics, the computed slopes between long bone lengths and circumferences (slenderness exponents) were compared with published values for mammals, and studied within a framework of the theoretical models of long bone scaling under gravity and muscle forces. Limb bone allometry in E. maximus and the Elephantidae is congruent with adaptation to bending and/or torsion induced by muscular forces during fast locomotion, as in other mammals, whereas the limb bones in L. africana appear to be adapted for coping with the compressive forces of gravity. Hindlimb bones are therefore more compliant than forelimb bones, and the resultant limb compliance gradient in extinct and extant elephants, contrasting in sign to that of other mammals, is shown to be a new important locomotory constraint preventing elephants from achieving a full-body aerial phase during fast locomotion. Moreover, the limb bone pattern of African elephants, indicating a noncritical bone stress not increasing with increments in body weight, explains why their mean and maximal body masses are usually above those for Asian elephants. Differences in ecology may be responsible for the subtle differences observed in vivo between African and Asian elephants, but they appear to be more pronounced when revealed via mechanical patterns dictated by limb bone allometry. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 16,29. [source] rhBMP-2/,BSM® Induces Significant Vertical Alveolar Ridge Augmentation and Dental Implant OsseointegrationCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2002Ulf M.E. Wikesjö DDS ABSTRACT Background: Recombinant human bone morphogenetic protein 2 (rhBMP-2) in a carrier has been shown to induce significant bone formation. Several candidate carriers, however, lack structural integrity to offset compressive forces that may compromise rhBMP-2 bone induction, in particular, for challenging onlay indications such as alveolar ridge augmentation. Purpose: The objective of this study was to evaluate rhBMP-2 in a calcium-phosphate cement carrier, ,BSM, for vertical alveolar ridge augmentation and immediate dental implant Osseointegration. Materials and Methods: Six adult Hound Labrador mongrels with 5 mm critical size supra-alveolar peri-implant defects were used. Three animals received rhBMP-2/,BSM (rhBMP-2 at 0.40 and 0.75 mg/mL) in contralateral jaw quadrants (total implant volume/defect , 1.5 mL). Three animals received ,BSM without rhBMP-2 (control group). The animals were euthanized at 16 weeks post surgery, and block biopsies were processed for histologie and histometric analysis. Results: rhBMP-2/,BSM induced substantial augmentation of the alveolar ridge. Control sites exhibited limited new bone formation. Vertical bone augmentation averaged (SD) 4.9 ± 1.0 mm (rhBMP-2 at 0.40 mg/mL), 5.3 ± 0.3 mm (rhBMP-2 at 0.75 mg/mL), and 0.4 ± 0.4 mm (control); new bone area 8.5 ± 4.2 mm 2, 9.0 ± 1.9 mm 2, and 0.5 ± 0.4 mm 2; new bone density 55.1 ± 6.4%, 61.1 ± 6.0%, and 67.7 ± 9.5%; and new bone-implant contact 26.9 ± 17.5%, 28.5 ± 1.4%, and 24.6 ± 16.1%, respectively. Residual ,BSM comprised 1% of the new bone. Bone density for the contiguous resident bone ranged from 65 to 71%, and bone-implant contact ranged from 49 to 64%. Conclusions: Surgical implantation of rhBMP-2/,BSM appears an effective protocol for vertical alveolar ridge augmentation procedures and immediate dental implant Osseointegration and for onlay indications of lesser complexity. [source] | |||||||||||||||||||