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Bone Substitute (bone + substitute)
Selected AbstractsEnamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defectsAUSTRALIAN DENTAL JOURNAL, Issue 1 2010M Esposito Background:, Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development. Objectives:, To test whether EMD is effective, and to compare EMD versus GTR, and various BG procedures for the treatment of intrabony defects. Search strategy:, We searched the Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE. Several journals were handsearched. No language restrictions were applied. Authors of randomized controlled trials (RCTs) identified, personal contacts and the manufacturer were contacted to identify unpublished trials. Most recent search: February 2009. Selection criteria:, RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR and various BG procedures with at least 1 year follow-up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, aesthetics and adverse events. The following time-points were to be evaluated: 1, 5 and 10 years. Data collection and analysis:, Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed. Main results:, Thirteen trials were included out of 35 potentially eligible trials. No included trial presented data after 5 years of follow-up, therefore all data refer to the 1-year time point. A meta-analysis including nine trials showed that EMD treated sites displayed statistically significant PAL improvements (mean difference 1.1 mm, 95% CI 0.61 to 1.55) and PPD reduction (0.9 mm, 95% CI 0.44 to 1.31) when compared to placebo or control treated sites, though a high degree of heterogeneity was found. Significantly more sites had <2 mm PAL gain in the control group, with RR 0.53 (95% CI 0.34 to 0.82). Approximately nine patients needed to be treated (NNT) to have one patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 25%. No differences in tooth loss or aesthetic appearance as judged by the patients were observed. When evaluating only trials at a low risk of bias in a sensitivity analysis (four trials), the effect size for PAL was 0.62 mm (95% CI 0.28 to 0.96), which was less than 1.1 mm for the overall result. Comparing EMD with GTR (five trials), GTR showed statistically significant more postoperative complications (three trials, RR 0.12, 95% CI 0.02 to 0.85) and more REC (0.4 mm 95% CI 0.15 to 0.66). The only trial comparing EMD with a bioactive ceramic filler found statistically significant more REC (-1.60 mm, 95% CI ,2.74 to ,0.46) at the EMG treated sites. Authors' conclusions:, One year after its application, EMD significantly improved PAL levels (1.1 mm) and PPD reduction (0.9 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD. Bone substitutes may be associated with less REC than EMD. Plain language summary:, Enamel matrix derivative (Emdogain®) for periodontal tissue regeneration in intrabony defects. Emdogain might have some advantages over other methods of regenerating the tissue supporting teeth lost by gum disease, such as less postoperative complications, but has not been shown to save more compromised teeth or that patients noticed any aesthetic improvement 1 year after its application. Bacteria in plaque can cause gum disease (periodontitis) that breaks down tissue supporting teeth. Surgical cleaning tries to stop the disease to save loose teeth. Bone grafting, guided tissue regeneration and enamel matrix derivatives (such as Emdogain) aim to regenerate support tissues. Emdogain contains proteins (derived from developing pig teeth) believed to regenerate tooth attachment. The review found that adjunctive application of Emdogain regenerates about 1 mm more tissue than surgical cleaning alone, although it is unclear to which extent such improvement is noticeable since patients did not find any difference in the aesthetic results. Emdogain showed similar clinical results to guided tissue regeneration, but is simpler to use and determines less complications. Bone substitutes may induce less gum retraction than Emdogain. No serious adverse reactions to Emdogain were reported in trials. [source] Interventions for replacing missing teeth: bone augmentation techniques for dental implant treatmentAUSTRALIAN DENTAL JOURNAL, Issue 1 2009M Esposito Background:, Dental implants require sufficient bone to be adequately stabilized. For some patients implant treatment would not be an option without bone augmentation. A variety of materials and surgical techniques are available for bone augmentation. Objectives:, General objectives: To test the null hypothesis of no difference in the success, function, morbidity and patient satisfaction between different bone augmentation techniques for dental implant treatment. Specific objectives: (A) to test whether and when augmentation procedures are necessary; (B) to test which is the most effective augmentation technique for specific clinical indications. Trials were divided into three broad categories according to different indications for the bone augmentation techniques: (1) major vertical or horizontal bone augmentation or both; (2) implants placed in extraction sockets; (3) fenestrated implants. Search strategy:, The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. Several dental journals were handsearched. The bibliographies of review articles were checked, and personal references were searched. More than 55 implant manufacturing companies were also contacted. Last electronic search was conducted on 9 January 2008. Selection criteria:, Randomized controlled trials (RCTs) of different techniques and materials for augmenting bone for implant treatment reporting the outcome of implant therapy at least to abutment connection. Data collection and analysis:, Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and odd ratios for dichotomous outcomes with 95% confidence intervals. The statistical unit of the analysis was the patient. Main results:, Seventeen RCTs out of 40 potentially eligible trials reporting the outcome of 455 patients were suitable for inclusion. Since different techniques were evaluated in different trials, no meta-analysis could be performed. Ten trials evaluated different techniques for vertical or horizontal bone augmentation or both. Four trials evaluated different techniques of bone grafting for implants placed in extraction sockets and three trials evaluated different techniques to treat bone dehiscence or fenestrations around implants. Authors' conclusions:, Major bone grafting procedures of resorbed mandibles may not be justified. Bone substitutes (Bio-Oss or Cerasorb) may replace autogenous bone for sinus lift procedures of atrophic maxillary sinuses. Various techniques can augment bone horizontally and vertically, but it is unclear which is the most efficient. It is unclear whether augmentation procedures at immediate single implants placed in fresh extraction sockets are needed, and which is the most effective augmentation procedure, however, sites treated with barrier plus Bio-Oss showed a higher position of the gingival margin when compared to sites treated with barriers alone. Non-resorbable barriers at fenestrated implants regenerated more bone than no barriers, however it remains unclear whether such bone is of benefit to the patient. It is unclear which is the most effective technique for augmenting bone around fenestrated implants. Bone morphogenetic proteins may enhance bone formation around implants grafted with Bio-Oss. Titanium may be preferable to resorbable screws to fixate onlay bone grafts. The use of particulate autogenous bone from intraoral locations, also taken with dedicated aspirators, might be associated with an increased risk of infective complications. These findings are based on few trials including few patients, sometimes having short follow up, and often being judged to be at high risk of bias. [source] Biomorphic Silicon Carbide Coated with an Electrodeposition of Nanostructured Hydroxyapatite/Collagen as Biomimetic Bone Filler and Scaffold,ADVANCED ENGINEERING MATERIALS, Issue 8 2010M. Lelli Abstract The paper describes the method of preparation and chemical/physical characterization of a new biomaterial to be used as a bone substitute and bone-tissue engineering scaffold, which synergistically joins a porous bio-inspired morphology and the mechanical properties of biomorphic silicon carbide (BioSiC) with the surface bioactivity of a nanostructured hydroxyapatite/collagen biomimetic coating. FT-IR spectroscopy and XRD techniques are utilized to determine the chemical coating's composition. The morphology and size of the inorganic and protein components are investigated by TEM. The characteristic morphology of BioSiC channels and pores, which differ as a function of the transversal or longitudinal cross-section and with etching time, are investigated by SEM. Natural wood transformed into BioSiC acts as a cathode in an electrochemically assisted process that produces on its surface a biomimetic coating of hydroxyapatite nanocrystals and reconstituted type I collagen fibrils, producing an innovative apatite/collagen biomimetic porous bone filler and scaffold for tissue engineering. [source] Step-wise treatment of two periodontal-endodontic lesions in a heavy smokerINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2008C. Walter Abstract Aim, To report a clinical case of two advanced periodontal-endodontic lesions with a focus on treatment issues related to tobacco use. Summary, A 53-year-old Caucasian male was referred to the School of Dentistry, Basel, Switzerland, for periodontal treatment. The major diagnoses were chronic (smoker) periodontitis and advanced combined periodontal-endodontic lesions on the mandibular left lateral incisor and right incisor. Conventional root canal treatment was performed, and subsequently led to reduced radiolucencies around the affected roots after 14 months. The remaining osseous defect was augmented by guided tissue regeneration using bovine bone substitute and resorbable membrane. The follow-up revealed a stable situation from clinical (probing depth 2,4 mm) and radiological points of view 32 months after initiation of treatment. Treatment considerations related to tobacco use are discussed. Key learning points, ,,After conventional root canal treatment, osseous healing should occur before further complementary therapy is taken into account. ,,Issues related to tobacco use have to be considered before treatment is initiated. [source] Release of gentamicin from bone regenerative materials: An in vitro studyJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007M. Teller Abstract Antibiotic loading of bone regenerative materials is a promising way to protect augmentation procedures from infection during the resorption phase of bone substitutes. Especially in the early stage of implantation, it should protect the grafted site against microbiological pathogens. The present study reports the release kinetics of gentamicin after loading from two synthetic bone filling materials. The first, BONITmatrix®, is a biphasic calcium phosphate silica composite obtained by the sol,gel route consisting of 13% silicon dioxide (w/w) and calcium phosphates (hydroxyapatite/,-tricalcium phosphate 60/40 w/w). The second, Synthacer®, is a sintered hydroxyapatite ceramic. Gentamicin was loaded by dipping and by vacuum coating. Release kinetics of the loaded Gentamicin was investigated by fluorescence polarization immunoassay and by staphylococcus aureus assay. By dipping, loading failed for Synthacer, and it was 12.7 mg gentamicin per gram bone substitute for BONITmatrix. By vacuum coating, loading was 11.3 mg gentamicin per gram bone substitute for Synthacer and 7.4 mg gentamicin per gram bone substitute for BONITmatrix. Distinct release kinetics were measured. For Synthacer, a high initial release was followed by a lower protracted release level up to 28 days. For BONITmatrix release was continuous over the investigated 70-day period. The present data suggest that the porosity properties at the nano- and microscopic levels, or the composition are responsible for antibiotic loading and subsequent release. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source] In vivo evaluation of hydroxyapatite foamsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 4 2002P. Sepulveda Abstract Hydroxyapatite (HA) is widely applied as bone graft material due to its osteoconductive potential and well-established biocompatibility. In this work, macroporous hydroxyapatite structures made through foaming of aqueous suspensions and gelcasting were tested for in vivo osteointegration. These foams are composed of a three-dimensional array of spherical pores with diameters of approximately 100,500 ,m, interconnected by windows of smaller size in the range of 30,120 ,m. The HA foams were implanted in the tibia of albino New Zealand rabbits and removed after a period of 8 weeks. Histological analysis revealed that the pores in the foams were partially or completely filled progressively with mature new bone tissue and osteoid after the implanted period. No immune or inflammatory reactions were detected. The high osteoconductive potential of the HA foams provides a potential structure for use as bone substitute in orthopedic, oral, and cranio-maxillofacial reconstructive surgery, and as dento-alveolar implants. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 587,592, 2002 [source] Evaluation of processed bovine cancellous bone matrix seeded with syngenic osteoblasts in a critical size calvarial defect rat modelJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2006U. Kneser Abstract Introduction: Biologic bone substitutes may offer alternatives to bone grafting procedures. The aim of this study was to evaluate a preformed bone substitute based on processed bovine cancellous bone (PBCB) with or without osteogenic cells in a critical size calvarial defect rat model. Methods: Discs of PBCB (Tutobone®) were seeded with second passage fibrin gel-immobilized syngenic osteoblasts (group A, n = 40). Cell-free matrices (group B, n = 28) and untreated defects (group C; n=28) served as controls. Specimens were explanted between day 0 and 4 months after implantation and were subjected to histological and morphometric evaluation. Results: At 1 month, bone formation was limited to small peripheral areas. At 2 and 4 months, significant bone formation, matrix resorption as well as integration of the implants was evident in groups A and B. In group C no significant regeneration of the defects was observed. Morphometric analysis did not disclose differences in bone formation in matrices from groups A and B. Carboxyfluorescine-Diacetate-Succinimidylester (CFDA) labeling demonstrated low survival rates of transplanted cells. Discussion: Osteoblasts seeded into PBCB matrix display a differentiated phenotype following a 14 days cell culture period. Lack of initial vascularization may explain the absence of added osteogenicity in constructs from group A in comparison to group B. PBCB is well integrated and represents even without osteogenic cells a promising biomaterial for reconstruction of critical size calvarial bone defects. [source] Submerged healing following surgical treatment of peri-implantitis: a case seriesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2007Ann-Marie Roos-Jansåker Abstract Objectives: The aim was to study a regenerative surgical treatment modality for peri-implantitis employing submerged healing. Material and Methods: Twelve patients, having a minimum of one osseointegrated implant with peri-implantitis, with a progressive loss of 3 threads (1.8 mm) following the first year of healing were involved in the study. After surgical exposure of the defect, granulomatous tissue was removed and the implant surface was treated using 3% hydrogen peroxide. The bone defects were filled with a bone substitute (Algipore®), a resorbable membrane (Osseoquest®) was placed over the grafted defect and a cover screw was connected to the fixture. The implant was then covered by flaps and submerged healing was allowed for 6 months. After 6 months the abutment was re-connected to the supra-structure. Results: A 1-year follow-up demonstrated clinical and radiographic improvements. Probing depth was reduced by 4.2 mm and a mean defect fill of 2.3 mm was obtained. Conclusion: Treatment of peri-implant defects using a bone graft substitute combined with a resorbable membrane and submerged healing results in defect fill and clinical healthier situations. [source] Surgical treatment of peri-implantitis using a bone substitute with or without a resorbable membrane: a prospective cohort studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2007Ann-Marie Roos-Jansåker Abstract Objectives: The aim of this prospective cohort study was to compare two regenerative surgical treatment modalities for peri-implantitis. Material and Methods: Thirty-six patients having a minimum of one osseointegrated implant, with a progressive loss of bone amounting to 3 threads (1.8 mm) following the first year of healing, combined with bleeding and/or pus on probing, were involved in this study. The patients were assigned to two different treatment strategies. After surgical exposure of the defect, granulomatous tissue was removed and the infected implant surface was treated using 3% hydrogen peroxide. The bone defects were filled with a bone substitute (Algipore®). In 17 patients (Group 1), a resorbable membrane (Osseoquest®) was placed over the grafted defect before suturing. In 19 patients (Group 2), the graft was used alone. Results: One-year follow-up demonstrated clinical and radiographic improvements. Probing depths were reduced by 2.9 mm in Group 1 and by 3.4 mm in Group 2. Defect fill amounted to 1.5 and 1.4 mm, respectively. There was no significant difference between the groups. Conclusion: It is possible to treat peri-implant defects with a bone substitute, with or without a resorbable membrane. [source] Deproteinized cancellous bovine bone (Bio-Oss®) as bone substitute for sinus floor elevationJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2003A retrospective, histomorphometrical study of five cases Abstract Objectives: To study in detail the performance of deproteinized cancellous bovine bone (DPBB, Bio-Osso®) granules as a bone substitute, a histomorphometric was performed on five patients treated with DPBB for reconstruction of the severely atrophic maxilla. Material and Methods: DPBB was used as mixture with autogenous bone particles, in concentrations that increased from 20% to 100% DPBB, with the time of healing increasing accordingly from 5 to 8 months. A total of 20 vertical biopsies was taken at the time of fixture installation and used for histomorphometry as undecalcified Goldner stained sections. Results: The results show that in all cases, the DPBB granules had been interconnected by bridges of vital newly formed bone. The volume of bone in the grafted area correlated inversely with the concentration of DPBB grafted, and varied between 37% and 23%. However, the total volume of mineralized material (bone plus DPI3B granules) remained within the same range in all five patients (between 53% and 59%). The high values for osteoid and resorption surface, and the presence of tartrate-resistant acid phosphatase-positive multinucleated osteoclasts in resorption lacunae, indicated that bone remodeling was very active in all grafts. Osteoclasts were also observed in shallow resorption pits on DPBB surfaces. The percentage DPBB surface in contact with bone remained stable at about 35% and could not be related to the proportion of DPBB grafted. Conclusion: Although the number of patients examined was limited, the data suggest that deproteinized cancellous bovine bone, preferably combined with autogenous bone particles, is a suitable material for sinus floor elevation in the severely atrophic human maxilla. Zusammenfassung Ent-Proteinisierter spöngiöser boviner Knochen (Bio-Oss) als Knochenersatz zur Sinusboden-Elevation. Eine retrospektive histomorphometrische Studie an 5 Fällen. Ziele:Um das Verhalten Ent-Proteinisierten spöngiösen bovinen Knochengranulats (DPBB, Bio,Oss) als Knochenersatzmaterial detailliert zu studieren, wurde an 5 Patienten, die mit DPBB zur Rekonstruktion der stark atrophischen Maxilla behandelt wurden, eine histomorphometrische Studie durchgeführt. Material und Methoden:DPBB wurde als Mischung mit autogenen Knochenpartikeln in einer Konzentration von 20 , 100% DPBB verwendet. Die Heilungsdauer wurde entsprechend von 5 auf 8 Monate erhöht. Zum Zeitpunkt der Implantatsetzung wurden insgesamt 20 vertikale Biopsien entnommen und für die Histomorphometrie als nicht-entkalkte, Goldner-gefärbte Schnitte verwendet. Ergebnisse: Die Ergebnisse zeigten in allen Fällen, dass die DPBB-Granula über Brücken von vitalem neu gebildetem Knochen miteinander verbunden waren. Das Volumen des Knochens in dem transplantiertem Gebiet korrelierte umgekehrt mit der Konzentration der transpantierten DPBB und variierte zwischen 37% und 23%. Jedoch lag das Gesamtvolumen des mineralisierten Materials (Knochen+DPBB-Granula)bei allen 5 Patienten im selben Bereich (zwischen 53% und 59%). Die hohen Werte für Ostoid und Resorptionsflächen sowie die Anwesenheit von TRAP-positiven multinukleären Osteoklasten in Resorptionslakunen, zeigte, dass das Knochenremodelling in allen Transplantaten sehr aktiv war. Auch in flachen Resorpionsgrübchen auf der DPBB-Oberfläche wurden Osteoklasten beobachtet. Der Prozentsatz der DPBB-Oberfläche welche im Knochenkontakt war blieb mit etwa 35% stabil und korrelierte nicht mit dem Anteil des transplantierten DPBBs. Schlussfolgerung:Obwohl die untersuchte Patientenzahl sehr gering ist, lassen die Daten vermuten, dass Ent-Proteinisierter spöngiöser boviner Knochen, vorzugsweise mit autogenen Knochenpartikeln kombiniert, ein geeignetes Material für die Sinusboden-Elevation bei stark atrophischer Maxilla ist. Résumé Os bovin spongieux déprotéiné comme substitut osseux dans l'épaississement sinusal. Une étude histomorphométrique rétrospective de cinq cas Le but de cette étude a été d'analyser en détail les performances de l'os bovin spongieux déprotéiné (DPBB, Bio-Oss®) en granules comme substitut osseux par une analyse histomorphométrique effectuée chez cinq patients traités pour une reconstruction au niveau d'un maxillaire sévèrement atrophié. DPBB a été utilisé en mélange avec des particules osseuses autogènes en concentrations augmentaient de 20 à 100% de DPBB, avec un temps de guérison augmentant paralèllement de cinq à huit mois. Vingt biopsies verticales ont ainsi été prélevées au moment du placement des implants et utilisées pour l'histomorphométrie sur coupes colorées Goldner non-décalcifiées. Les résultats ont indiqué que dans tous les cas les granules DPBB ont été interconnectées par des bridges d'os néoformé vivant. Le volume d'os dans l'aire greffée était en corrélation inverse avec les concentrations de DPBB greffées et variait entre 37 et 23 %. Cependant le volume total de matériel minéralisé (os+granules DPBB) restait dans les mêmes moyennes chez les cinq patients (entre 53 et 59 %). Les valeurs importantes pour la surface de résorption et ostéides, et la présence d'ostéoclastes multinucléaires positifs au TRAP dans les lacunes de résorption indiquaient que le remodelage osseux était très actif dans tous les greffons. Les ostéoclastes étaient également observés dans des petites crevasses de résorption étroites sur les surfaces DPBB. Le pourcentage DPBB en contact avec l'os demeurait stable à environ 35% et ne pouvait pas être mis en relation avec la proportion de DPBB greffé. Bien que le nombre de patients examinés aie été très limité, les données suggèrent que l'os bovin spongieux déprotéiné de préférence en combinaison avec des particules d'os autogène est un bon matériel pour l'épaississement du plancher sinusal en présence de maxillaire humain sévèrement atrophié. [source] Targeted mechanical properties for optimal fluid motion inside artificial bone substitutesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2009L.D. Blecha Abstract Our goal was to develop a method to identify the optimal elastic modulus, Poisson's ratio, porosity, and permeability values for a mechanically stressed bone substitute. We hypothesized that a porous bone substitute that favors the transport of nutriments, wastes, biochemical signals, and cells, while keeping the fluid-induced shear stress within a range that stimulates osteoblasts, would likely promote osteointegration. Two optimization criteria were used: (i) the fluid volume exchange between the artificial bone substitute and its environment must be maximal and (ii) the fluid-induced shear stress must be between 0.03 and 3 Pa. Biot's poroelastic theory was used to compute the fluid motion due to mechanical stresses. The impact of the elastic modulus, Poisson's ratio, porosity, and permeability on the fluid motion were determined in general and for three different bone substitute sizes used in high tibial osteotomy. We found that fluid motion was optimized in two independent steps. First, fluid transport was maximized by minimizing the elastic modulus, Poisson's ratio, and porosity. Second, the fluid-induced shear stress could be adjusted by tuning the bone substitute permeability so that it stayed within the favorable range of 0.03 to 3 Pa. Such method provides clear guidelines to bone substitute developers and to orthopedic surgeons for using bone substitute materials according to their mechanical environment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 1082,1087, 2009 [source] A composite material model for improved bone formationJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 7 2010Silvia Scaglione Abstract The combination of synthetic polymers and calcium phosphates represent an improvement in the development of scaffolds for bone-tissue regeneration. Ideally, these composites provide both mechanically and architecturally enhanced performances; however, they often lack properties such as osteoconductivity and cell bioactivation. In this study we attempted to generate a composite bone substitute maximizing the available osteoconductive surface for cell adhesion and activity. Highly porous scaffolds were prepared through a particulate leaching method, combining poly-,-caprolactone (PCL) and hydroxyapatite (HA) particles, previously coated with a sucrose layer, to minimize their embedding by the polymer solution. Composite performances were evaluated both in vitro and in vivo. In PCL,sucrose-coated HA samples, the HA particles were almost completely exposed and physically distinct from the polymer mesh, while uncoated control samples showed ceramic granules massively covered by the polymer. In vivo results revealed a significant extent of bone deposition around all sucrose-coated HA granules, while only parts of the control uncoated HA granules were surrounded by bone matrix. These findings highlight the possibility of generating enhanced osteoconductive materials, basing the scaffold design on physiological and cellular concepts. Copyright © 2010 John Wiley & Sons, Ltd. [source] Hemispheric brain volume replacement with free latissimus dorsi flap as first step in skull reconstructionMICROSURGERY, Issue 4 2005Anton H. Schwabegger M.D. Large skull defects lead to progressive depression deformities, with resulting neurological deficits. Thus, cranioplasty with various materials is considered the first choice in therapy to restore cerebral function. A 31-year-old female presented with a massive left-sided hemispheric substance defect involving bone and brain tissue. Computed tomography showed a substantial convex defect involving the absence of calvarial bone as well as more than half of the left hemisphere of the brain, with a profound midline shift and a compression of the ventricular system. There was a severe problem due to multiple deep-skin ulcerations at the depression margin, prone to skin perforation with a probability of intracranial infection. In a first step, a free myocutaneous latissimus dorsi flap was transplanted for volume replacement of the hemispheric brain defect, and 4 months later, artificial bone substitute was implanted in order to prevent progressive vault depression deformity. Healing was uneventful, and the patient showed definite neurological improvement postoperatively. Free tissue transfer can be a valuable option in addition to cranioplasty in the treatment of large bony defects of the skull. Besides providing stable coverage for the reconstructed bone or its substitute, it can also serve as a volume replacement. © 2005 Wiley-Liss, Inc. Microsurgery 25:325,328, 2005. [source] Osteogenic Evaluation of Glutaraldehyde Crosslinked Gelatin Composite with Fetal Rat Calvarial Culture ModelARTIFICIAL ORGANS, Issue 8 2001Hwa-Chang Liu Abstract: The cytotoxicity of the synthetic bone substitute composed of tricalcium phosphate and glutaraldehyde crosslinked gelatin (GTG) were evaluated by osteoblast cell culture. In a previous study, the GTG composites were soaked in distilled water for 1, 2, 4, 7, 14, 28, and 42 days, and then the solutions (or extracts) were cocultured with osteoblasts to evaluate the cytotoxicity of GTG composites by alive cell counting. In this study, the extracts were cocultured with the osteoblasts; thereafter, the concentration of transforming growth factor-, (TGF-,1) and prostaglandin E2 (PGE2) in the medium was analyzed to strictly reflect the biological effects of GTG composites on the growth of osteoblasts. In order to investigate the osteoconductive potential of the GTG composites on new bone formation in a relative short term, a model of neonatal rat calvarial organ culture was designed prior to animal experiments. Three experimental materials of 4, 8, and 12% GTG composites were evaluated by fetal rat calvarial organ culture for their ability for bone regeneration. Deproteinized bovine and porcine cancellous bone matrixes were used as the controlled materials. All the organ culture units were maintained in cultured medium for 5 weeks. Following the culture period, the morphology of tissue was observed under an optical microscope, and the quantitative evaluation of the new generation bone was determined by using a semiautomatic histomorphometeric method. Except in the initial 4 days, the concentration of TGF-,1 of 4% and 8% GTG composites was higher than that of the blank group for all the other experimental time periods. The PGE2 concentration for 4% and 8% GTG composites was lower than that of the blank group. It revealed that the 4% and 8% GTG composites would not lead to inflammation and would promote osteoblast growth. The morphology and activity of the osteoblasts were not transformed or changed by the 2 GTG composites. For the 12% GTG composite, the performance of the in vitro condition was inferior to the blank group and the other 2 GTG composites. Although the concentration of TGF-,1 and PGE2 was gradually back to normal after 14 days, the morphology of the osteoblasts was abnormal with features such as contracted cytoplast structures. The osteoblast was damaged perhaps in the initial stage. We suggested that the 4% and 8% GTG composites should be soaked in distilled water at least for 4 days before medical applications. The 12% GTG composite and the composites with a concentration of glutaraldehyde solution higher than 12% were not recommended as a medical prostheses in any condition. The fetal rat calvaria culture also showed the same results with the analysis of TGF-,1 and PGE2. From the study, we could predict the results of animal experiments in the future. [source] Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trialCLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2010Nikos Mardas Abstract Objectives: The aim of this randomized, controlled clinical trial was to compare the potential of a synthetic bone substitute or a bovine-derived xenograft combined with a collagen membrane to preserve the alveolar ridge dimensions following tooth extraction. Methods: Twenty-seven patients were randomized into two treatment groups following single tooth extraction in the incisor, canine and premolar area. In the test group, the alveolar socket was grafted with Straumann Bone Ceramic® (SBC), while in the control group, Bio-Oss® deproteinized bovine bone mineral (DBBM) was applied. In both groups, a collagen barrier was used to cover the grafting material. Complete soft tissue coverage of the barriers was not achieved. After 8 months, during re-entry procedures and before implant placement, the horizontal and vertical dimensions of the residual ridge were re-evaluated and trephine biopsies were performed for histological analysis in all patients. Results: Twenty-six patients completed the study. The bucco-lingual dimension of the alveolar ridge decreased by 1.1±1 mm in the SBC group and by 2.1±1 in the DBBM group (P<0.05). Both materials preserved the mesio-distal bone height of the ridge. No differences in the width of buccal and palatal bone plate were observed between the two groups. The histological analysis showed new bone formation in the apical part of the biopsies, which, in some instances, was in direct contact with both SBC and DBBM particles. The coronal part of the biopsies was occupied by a dense fibrous connective tissue surrounding the SBC and DBBM particles. Conclusion: Both biomaterials partially preserved the width and the interproximal bone height of the alveolar ridge. To cite this article: Mardas N, Chadha V, Donos N. Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trial. Clin. Oral Impl. Res. 21, 2010; 688,698. [source] Human osteoclast formation and activity on an equine spongy bone substituteCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2009Vittoria Perrotti Abstract Objectives: The aim of the present study was to evaluate the in vitro formation and activity of human osteoclasts (OCLs) generated on a new type of xenograft for bone substitution, an equine spongy bone. Material and methods: Peripheral blood mononuclear cells from healthy volunteers were used to generate OCLs in vitro in the presence of macrophage colony stimulating factor (M-CSF) and receptor activator of NF-,B ligand (RANKL) on bovine bone slices (positive control) and equine spongy bone. Morphological and biochemical methods were used to assess OCLs formation and activity. Results: Cells generated after 21 days of culture on equine spongy bone showed similar morphology to those on the positive control and displayed typical OCL markers and features, indicating that this material supported OCL formation. Moreover, these cells were functionally active on equine spongy bone with statistically significant differences compared with the control in the release of tartrate-resistant acid phosphatase (TRAcP5b) at days 14 and 21 of culture. With regard to the resorption, on equine bone, OCLs formed smaller discontinuous island-like lacunae rather than the typical lobulated, tracking resorption lacunae observed on the control. Conclusions: This study enables clinicians to tailor the usage of equine spongy bone and presents a model, which can be applied to the preclinical assessment of bone substitute material's resorbability and resorption rates. [source] Histologic findings at augmented bone areas supplied with two different bone substitute materials combined with sinus floor liftingCLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2004Report of one case Abstract: This case report is focused on the histologic findings of bone tissue supplied with two different hydroxyapatites (HAs) used for maxillary sinus floor grafting in the same patient after various healing intervals. An insufficient unilateral sinus floor grafting with Bio-Oss® biomaterial was followed by an additional grafting procedure with Algipore® biomaterial performed 4 years later. Bone samples obtained during second-stage dental implantation contained the interesting combination of Bio-Oss®, a bovine anorganic bone substitute, and Algipore®, a porous algae-derived HA, in close vicinity, yet after different healing periods. Light microscopy exhibited satisfactory osseointegration of both grafting materials. However, Bio-Oss® biomaterial showed no evidence of substantial remodeling after a healing period of 4.5 years. On the other hand, Algipore® particles demonstrated signs of remodeling by being locally resorbed and partially replaced with newly formed bone already within 6 months. Résumé Ce rapport d'un cas se concentre sur les découvertes histologiques du tissu osseux apporté par deux hydroxyapatites différents utilisés pour l'épaississement du plancher sinusal chez le même patient après différents intervalles de guérison. Un épaississement sinusal unilatéral insuffisant effectué avec le Bio-Oss® a été suivi d'un nouveau processus d'épaississement avec le Algipore® (un hydroxyapatite biologique dérivé d'algues marines calcifiées) quatre ans plus tard. Des échantillons osseux obtenus durant le placement des implants contenaient la combinaison intéressante du Bio-Oss®, un substitut osseux inorganique bovin, et du Algipore®, un hydroxyapatite d'algues, l'un à côté de l'autre, même si il y avait des périodes de guérison différentes. La microscopie optique a montré une ostéoïntégration satisfaisante des deux matériaux greffés. Cependant, le Bio-Oss® ne montrait aucune évidence d'un remodelage substantiel après une période de 4,5 années. Par contre les particules de Algipore® possèdaient des signes de remodelage tout en étant résorbées localement et partiellement remplacées par de l'os néoformé déjà après six mois. Zusammenfassung Diese Fallvorstellung präsentiert die Histologie eines Knochens, der bei einer in zwei Schritten und mit verschiedenen Hydroxylapatitprodukten durchgeführten Sinusbodenelevation entstanden ist. Die Einheilzeit der zwei Transplantate war verschieden lang. Eine einseitig durchgeführte und ungenügende Sinusbodenelevation mit dem Biomaterial Bio-Oss® wurde vier Jahre später mit einem zusätzlichen Augmentationseingriff unter Einsatz des Biomaterials Algipore® korrigiert. Bei der Implantation konnte man Knochenproben von interessanter Zusammensetzung entnehmen. Es handelte sich um einen Knochen, der während verschieden langer Zeit in engem Kontakt mit Bio-Oss®, einem anorganischen Rinderknochentransplantat, und Algipore®, einem porösen aus Algen gewonnenem Hydroxylapatit stand. Die Lichtmikroskopie zeigte eine zufriedenstellende Osseointegration beider Transplantatmaterialien. Bio-Oss® zeigte jedoch nach einer Einheilzeit von 4.5 Jahren noch keine Anzeichen einer substanziellen Remodellation. Bei den Algipore® Partikeln war dies bereits der Fall. Sie waren schon nach sechs Monaten an einigen Stellen anresorbiert, teilweise sogar mit neu gebildetem Knochen ersetzt. Resumen Este informe de un caso esta enfocado sobre los hallazgos histológicos de tejido óseo suministrado con dos diferentes hidroxiapatitas usadas para injerto del suelo del seno maxilar en el mismo paciente tras varios intervalos de cicatrización. Un insuficiente injerto del suelo del seno con biomaterial Bio-Oss® fue seguido por un procedimiento adicional de injerto con biomaterial Algipore® llevado a cabo 4 años mas tarde. Las muestras de hueso obtenidas durante la segunda fase de la implantación dental contenían una interesante combinación de Bio-Oss®, un sustituto óseo inorgánico bovino y Algipore®, una hidroxiapatita porosa derivada de algas, en próxima vecindad, aunque tras diferentes periodos de cicatrización. La microscopía óptica exhibió una osteointegración satisfactoria de ambos materiales de injerto. De todos modos, el biomaterial Bio-Oss® no mostró evidencia de un remodelado sustancial tras un periodo de cicatrización de 4.5 años. Por otro lado las partículas de Algipore® demostraron signos de remodelado al ser localmente reabsorbidas y reemplazadas parcialmente con hueso neoformado ya a los 6 meses. [source] Histological assessment of augmented jaw bone utilizing a new collagen barrier membrane compared to a standard barrier membrane to protect a granular bone substitute materialCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2002A randomized clinical trial Abstract: Successful bone augmentation requires predictable space maintenance and adequate exclusion of those cells that lack osteogenetic potential from the defect area. Natural bone mineral is considered to be osteoconductive and is used as space maker in combination with membrane barrier techniques. The aim of this study was to compare qualitative histological results achieved by using deproteinized bovine bone mineral (DBBM) as a space maintainer and a new collagen barrier (OssixÔ, test group) vs. the same bone substitute and the standard e-PTFE membrane (Gore-Tex®, control group). Twenty-eight patients were randomly assigned to the test or the control group. Seven months after augmentation procedures, biopsies were obtained at reentry and were analysed histomorphometrically. In all, 14 specimens of group I (test group, OssixÔ) and 13 specimens of group II (controls, PTFE-membranes) showed close qualitative similarity of their histologies. Histomorphometrically, total mineralized bone area was 42% ± 18% in group I vs. 39% ± 15% in group II. The unmineralized tissue area was 44% ± 15% vs. 46% ± 12% and the area of DBBM remnants 14% ± 9% and 15% ± 12%, respectively. The differences were statistically nonsignificant (Mann,Whitney test). The occurrence of barrier exposure did not interfere with the histological outcome either in the test or in the control group. The new collagen barrier combined with the DBBM provided qualitative bone regeneration comparable to the standard e-PTFE material combined with the same mineral. [source] Bovine-HA spongiosa blocks and immediate implant placement in sinus augmentation proceduresCLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2002Histopathological, histomorphometric observations on different histological stainings in 10 consecutive patients Abstract: Bovine mineral spongiosa block (B-SB) was used as a bone substitute in sinus augmentation procedures in 10 consecutive patients. Implants were placed during the same session. The purpose of this study was to histopathologically examine the healing of the grafted site around the implants at 12 months. Radiographic follow-up showed apparent bone apposition in the augmented area around the implants. Clinically, all 36 implants were stable and integrated with the surrounding tissue. Histopathologically, new bone formation was evident in all specimen hard tissue cores. Hydroxyapatite particles were present in direct contact with the remodeled osseous tissue. Mallory trichrome staining showed different stages of mineralization and maturation of the newly formed bone around the grafted mineral particles. Morphometric evaluation of Picrosirius red stained slides under polarized light microscopy was performed at the peripheral/external and deep section slides of all specimens. The average bone area fraction was 34.2%, with a 1 : 5.4 mean lamellar/woven bone ratio at the peripheral side and 53.0%, with 1 : 2.5 mean ratio at the deep side. The differences of both parameters between the two sites were statistically significant. B-SB proved to be a suitable grafting material with simultaneously placed implants in sinus floor augmentation procedures. [source] Bone replacement following dental trauma prior to implant surgery , present statusDENTAL TRAUMATOLOGY, Issue 1 2009Mats Hallman Although autogenous bone grafts is considered the ,gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has increased. Today, a substantial number of biomaterials are available on the market, but only a few are well documented. The user should be aware that these biomaterials have different properties: resorbable or non-resorbable, time of resorption and resorption mechanism. The purpose of this review is to describe the function of various bone substitutes and indications for their use in reconstructive implant surgery and to give an overview of the current situation. [source] 3D Powder Printing of ,-Tricalcium Phosphate Ceramics Using Different Strategies,ADVANCED ENGINEERING MATERIALS, Issue 12 2008E. Vorndran Custom made macroporous ,-tricalcium phosphate (,-TCP) bone substitutes were fabricated using 3D powder printing comparing three different preparation strategies. Samples fabricated using a novel hydraulic cement setting reaction showed the best printing resolution and highest mechanical performance. This method is a significant step forward in producing ,-TCP monoliths by rapid prototyping and would decrease processing time for commercial fabrication due to their rapid hardening and ease of handling. [source] Release of gentamicin from bone regenerative materials: An in vitro studyJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007M. Teller Abstract Antibiotic loading of bone regenerative materials is a promising way to protect augmentation procedures from infection during the resorption phase of bone substitutes. Especially in the early stage of implantation, it should protect the grafted site against microbiological pathogens. The present study reports the release kinetics of gentamicin after loading from two synthetic bone filling materials. The first, BONITmatrix®, is a biphasic calcium phosphate silica composite obtained by the sol,gel route consisting of 13% silicon dioxide (w/w) and calcium phosphates (hydroxyapatite/,-tricalcium phosphate 60/40 w/w). The second, Synthacer®, is a sintered hydroxyapatite ceramic. Gentamicin was loaded by dipping and by vacuum coating. Release kinetics of the loaded Gentamicin was investigated by fluorescence polarization immunoassay and by staphylococcus aureus assay. By dipping, loading failed for Synthacer, and it was 12.7 mg gentamicin per gram bone substitute for BONITmatrix. By vacuum coating, loading was 11.3 mg gentamicin per gram bone substitute for Synthacer and 7.4 mg gentamicin per gram bone substitute for BONITmatrix. Distinct release kinetics were measured. For Synthacer, a high initial release was followed by a lower protracted release level up to 28 days. For BONITmatrix release was continuous over the investigated 70-day period. The present data suggest that the porosity properties at the nano- and microscopic levels, or the composition are responsible for antibiotic loading and subsequent release. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source] Evaluation of processed bovine cancellous bone matrix seeded with syngenic osteoblasts in a critical size calvarial defect rat modelJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 3 2006U. Kneser Abstract Introduction: Biologic bone substitutes may offer alternatives to bone grafting procedures. The aim of this study was to evaluate a preformed bone substitute based on processed bovine cancellous bone (PBCB) with or without osteogenic cells in a critical size calvarial defect rat model. Methods: Discs of PBCB (Tutobone®) were seeded with second passage fibrin gel-immobilized syngenic osteoblasts (group A, n = 40). Cell-free matrices (group B, n = 28) and untreated defects (group C; n=28) served as controls. Specimens were explanted between day 0 and 4 months after implantation and were subjected to histological and morphometric evaluation. Results: At 1 month, bone formation was limited to small peripheral areas. At 2 and 4 months, significant bone formation, matrix resorption as well as integration of the implants was evident in groups A and B. In group C no significant regeneration of the defects was observed. Morphometric analysis did not disclose differences in bone formation in matrices from groups A and B. Carboxyfluorescine-Diacetate-Succinimidylester (CFDA) labeling demonstrated low survival rates of transplanted cells. Discussion: Osteoblasts seeded into PBCB matrix display a differentiated phenotype following a 14 days cell culture period. Lack of initial vascularization may explain the absence of added osteogenicity in constructs from group A in comparison to group B. PBCB is well integrated and represents even without osteogenic cells a promising biomaterial for reconstruction of critical size calvarial bone defects. [source] Implants placed in combination with an internal sinus lift without graft material: an analysis of short-term failureJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2009Olaf Gabbert Abstract Aim: Investigation of the short-term survival of implants placed in combination with an internal sinus lift (ISL) without graft material. Material and Methods: Thirty-six patients received 92 screw-shaped dental implants in combination with an ISL. No bone grafts or bone substitutes were used. Forty-four patients with 77 implants in the native posterior maxilla served as controls. X-rays taken after implant placement and 6 months later were evaluated for the presence of bone gain at the apical aspect of the implants. Kaplan,Meier survival curves and Cox regression analysis were used to estimate survival curves and to isolate risk factors for implant failures. Results: Within a mean observation period of 1.2 years (minimum 9 months; maximum 3.7 years), four failures were recorded in the experimental group and two in the controls. The probability of survival was above 94% for both groups. Six,nine months after surgery, bone gain was observed in 29 out of 92 implants. Comparison of the experimental group and controls revealed no effect of ISL and membrane perforation on the probability of survival. Conclusions: Promising short-term outcomes were observed for implants with ISL without graft material; for a substantial proportion of implants, apical bone gain was observed in the first 6,9 months. [source] Targeted mechanical properties for optimal fluid motion inside artificial bone substitutesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2009L.D. Blecha Abstract Our goal was to develop a method to identify the optimal elastic modulus, Poisson's ratio, porosity, and permeability values for a mechanically stressed bone substitute. We hypothesized that a porous bone substitute that favors the transport of nutriments, wastes, biochemical signals, and cells, while keeping the fluid-induced shear stress within a range that stimulates osteoblasts, would likely promote osteointegration. Two optimization criteria were used: (i) the fluid volume exchange between the artificial bone substitute and its environment must be maximal and (ii) the fluid-induced shear stress must be between 0.03 and 3 Pa. Biot's poroelastic theory was used to compute the fluid motion due to mechanical stresses. The impact of the elastic modulus, Poisson's ratio, porosity, and permeability on the fluid motion were determined in general and for three different bone substitute sizes used in high tibial osteotomy. We found that fluid motion was optimized in two independent steps. First, fluid transport was maximized by minimizing the elastic modulus, Poisson's ratio, and porosity. Second, the fluid-induced shear stress could be adjusted by tuning the bone substitute permeability so that it stayed within the favorable range of 0.03 to 3 Pa. Such method provides clear guidelines to bone substitute developers and to orthopedic surgeons for using bone substitute materials according to their mechanical environment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 1082,1087, 2009 [source] Current concepts in periodontal bioengineeringORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2005M Taba Jr Abstract Authors ,, Taba Jr M, Jin Q, Sugai JV, Giannobile WV Repair of tooth supporting alveolar bone defects caused by periodontal and peri-implant tissue destruction is a major goal of reconstructive therapy. Oral and craniofacial tissue engineering has been achieved with limited success by the utilization of a variety of approaches such as cell-occlusive barrier membranes, bone substitutes and autogenous block grafting techniques. Signaling molecules such as growth factors have been used to restore lost tooth support because of damage by periodontal disease or trauma. This paper will review emerging periodontal therapies in the areas of materials science, growth factor biology and cell/gene therapy. Several different polymer delivery systems that aid in the targeting of proteins, genes and cells to periodontal and peri-implant defects will be highlighted. Results from preclinical and clinical trials will be reviewed using the topical application of bone morphogenetic proteins (BMP-2 and BMP-7) and platelet-derived growth factor-BB (PDGF) for periodontal and peri-implant regeneration. The paper concludes with recent research on the use of ex vivo and in vivo gene delivery strategies via gene therapy vectors encoding growth promoting and inhibiting molecules (PDGF, BMP, noggin and others) to regenerate periodontal structures including bone, periodontal ligament and cementum. [source] Minimally Invasive Antral Membrane Balloon Elevation , Results of a Multicenter RegistryCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2009Efraim Kfir DMD ABSTRACT Background and Purpose: Frequently, the posterior maxilla lacks sufficient bone mass to support dental implants. This multiphysician registry assessed the feasibility and safety of minimally invasive antral membrane balloon elevation (MIAMBE), followed by bone augmentation and implant fixation. Materials and Methods: One hundred twelve consecutive patients were referred for MIAMBE. Following pre-procedural assessment and informed consent, patients underwent alveolar crest exposure, and 3 mm osteotomy followed by MIAMBE. Platelet-rich fibrin and bone substitutes were injected under the antral membrane; implant placement and primary closure were executed at the same sitting. Implant loading was carried out 6 to 9 months later. Results: One hundred nine (97.3%) patients successfully concluded the initial procedure. Three patients had membrane tear requiring procedure abortion. One case of infection was documented at 4 weeks. Procedure time was 58 ± 23 minutes. Incremental bone height consistently exceeded 10 mm, and implant survival of 95% was observed at 6 to 9 months. Conclusion: MIAMBE can be applied to all patients in need of posterior maxilla bone augmentation with high procedural success, low complication rate, and satisfactory bone augmentation and implant survival. As it is minimally invasive and associated with minimal discomfort, MIAMBE should be an alternative to the currently employed methods of maxillary bone augmentation. [source] Alveolar Ridge Regeneration with Equine Spongy Bone: A Clinical, Histological, and Immunohistochemical Case SeriesCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2009Danilo Alessio Di Stefano DDS ABSTRACT Background: In the case of localized ridge atrophy, a ridge augmentation procedure, with the use of bone substitutes and barrier membranes, may then be necessary. Purpose: The aim of the present study was a clinical, histological, and immunohistochemical evaluation of an equine spongy bone in alveolar ridge augmentation procedures. Materials and Methods: Five patients showing horizontal mandibular ridge defects participated in this study. A ridge augmentation was performed through an onlay apposition of equine bone covered by a titanium-reinforced membrane. After 6 months of healing, five bone cores from nonaugmented sites (control) and five from augmented sites (test) were retrieved. Results: In test sites, no postoperative complications occurred. Horizontal bone width increased from ,4 to ,7 mm. In control sites, the newly formed bone represented 33%, and in test sites, 35% of the total area. The mean value of the microvessel density was 25.6 +/, 3.425 per mm2 in controls, while 33.3 +/, 2.5 vessels per mm2 in the test sites were found (p < .05). Both groups showed a high intensity (++) of vascular endothelial growth factor expression in the newly formed bone, while a low intensity (+) was found in the mature bone. Conclusion: Equine bone appeared to be biocompatible and to be associated with new vessel ingrowth. Within the limits of the small sample size, the present study indicated that equine bone could be used in mandibular ridge augmentations. [source] A 5-Year Prospective Follow-Up Study of Implant-Supported Fixed Prostheses in Patients Subjected to Maxillary Sinus Floor Augmentation with an 80:20 Mixture of Bovine Hydroxyapatite and Autogenous BoneCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2004Mats Hallman DDS ABSTRACT Background: Prospective long-term follow-up studies evaluating the use of bone substitutes to enable dental implant placement and integration are rare. Purpose: This study was undertaken to evaluate the survival rate of dental implants placed 6 months after maxillary sinus floor augmentation using a mixture of 80% bovine hydroxyapatite (BH) and 20% autogenous bone (AB). Material and Methods: Twenty patients subjected to 30 maxillary sinus floor grafting procedures using fibrin glue and an 80:20 mixture of BH and AB to enable placement of dental implants 6 months later were followed for 5 years of functional loading. Clinical and radiographic examinations of the grafts and implants were performed. Results: After 5 years of functional loading with fixed bridges, 15 of 108 implants had been lost, giving a cumulative survival rate of 86%. The mean marginal bone loss after 5 years was 1.3 ± 1.1 mm. Conclusion: Grafting of the maxillary sinus with a mixture of BH and AB and later placements of turned implants could be performed with predictable long-term results. All but one of the patients who were observed had functional fixed bridges after 5 years of functional loading. [source] Immunoexpression of Cbfa-1/Runx2 and VEGF in sinus lift procedures using bone substitutes in rabbitsCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2010Leandro Soeiro De Souza Nunes Abstract Objectives: To analyze and compare the expression of core binding factor-1 (Cbfa-1)/Runx2 and vascular endothelium growth factor (VEGF) in sinus lift procedures using bovine hydroxyapatite (HA) and ,-tricalcium phosphate (,-TCP). Material and Methods: Twenty-four male rabbits that had undergone bilateral sinus lift procedures were divided into three groups, according to the sinus filling material: Group 1: autogenous bone graft; Group 2: bovine HA; and Group 3: ,-TCP. All groups were sacrificed after 7, 14, 30 and 60 days, for microscopic, histomorphometry and immunohistochemistry analysis. Results: Microscopic analysis showed a similar bone repair pattern between the tested groups. New bone formation, soft and medular tissue, remaining material or particulate bone graft area were obtained by histomorphometric analysis. After 14 days, statistically significant differences in new bone formation were found between Group 1 (27.76±7.8) and Groups 2 (14.22±3.2) and 3 (11.1±7.7). After 30 days, statistically significant differences (P<0.05) were detected in bone formation between Groups 1 (31.39±36.5) and 2 (14.13±3.2). The last period showed improved bone formation in Group 2. Also, Group 2 showed higher Cbfa-1/Runx2 immunoexpression when compared with Group 3. No remarkable differences were observed in VEGF immunoexpression among groups. Conclusion: Taken together, both biomaterials allowed bone tissue growth in a conductive pattern and did not interfere with bone remodeling in the late period, with a slight improvement in bone tissue formation when using HA, confirmed by marked expression of Cbfa-1 at initial periods. To cite this article: Nunes LSS, De Oliveira RV, Holgado LA, Nary Filho H, Ribeiro DA, Matsumoto MA. Immunoexpression of Cbfa-1/Runx2 in sinus lift procedures using bone substitutes in rabbits. Clin. Oral Impl. Res. 21, 2010; 584,590. doi: 10.1111/j.1600-0501.2009.01858.x [source] | |||||||||||||