Biological analysis of an innovative biodegradable antibiotic eluting bioactive glass/gypsum composite bone cement for treating experimental chronic MRSA osteomyelitis / 药物分析学报

A multi-barrier antibiotics loaded biodegradable composite bone cement for resolving chronic osteo-myelitis has been studied to understand the physico-mechanical properties,drug loading/eluting effi-ciency,and different merits and demerits prior to clinical application.After successful induction of bone infection in 28 rabbits using methicillin-resistant Staphylococcus aureus(MRSA)strains,calcium sulfate/bioactive glass based composite cement was implanted in 12 defects to assess its performance over parenteral therapy with microscopic and radiological examination for 90 days.The composite cement revealed acceptable physico-mechanical properties and controlled drug elution kinetics.Furthermore,the antibiotics concentrations in bone up to 42 days were sufficient to kill MRSA without eliciting adverse drug reactions.The striking feature of platelets aggregation by composite cement could assist bone healing.The controlled degradation with simultaneous entrapment of composite cement within the osteoid tissues and complete repair of infected cortical defects(holes)in rabbit tibia at 6 weeks indicated the excellent anti-infective and osteoconductive properties of composite cement.Thus,the animal study demonstrated the superiority of composite over injectable antibiotic therapy based on infection reso-lution and bone regeneration.We thereby conclude that the composite cement can be effectively applied in the treatment of resistant cases of chronic osteomyelitis.

Use of a morcellized fragment of bone as a bone graft in a femoral fracture repair / Uso de fragmento ósseo morcelizado como enxerto ósseo no reparo de fratura femoral

As one of the most frequent reasons for presentation at the orthopedic services in veterinary practice, long bone fractures need bone continuity for consolidation to take place. This case report has demonstrates the use of a morcellized fragment of bone as a bone graft in a femoral fracture with major bone loss. A mixed-breed adult cat with a segmental femoral fracture with a large longitudinal fissure in the central bone fragment was submitted to an interlocking nail osteosynthesis. During the procedure a fracture occurred along the fissure resulting in two bone fragments with significant bone loss. Fragments were morcellized and applied over the defect to act as a bone graft. By the 15th day after the surgery, the cat had a normal gait and showed no pain response, and bone consolidation occurred after 7 months. Once harvesting of humeral, femoral and tibial bone grafts can be frustrating in cats, resulting in just small amounts of bone, the morcellation of the central fragments was vital to provide sufficient graft to cover the big defect in the femoral shaft. The authors suggest that autologous fresh morcellized cortical bone fragments can be an adjunct to the treatment of comminuted fractures in cats, as an alternative to more traditional repairs of comminuted fracture.

Fraturas de ossos longos necessitam de continuidade óssea para que a consolidação ocorra. Este relato de caso tem como objetivo demonstrar o uso de um fragmento ósseo morcelizado com a função de enxerto ósseo em uma fratura de fêmur com presença de uma grande falha óssea entre os fragmentos. Um gato adulto, sem raça definida, com uma fratura múltipla em fêmur com presença de uma fissura longitudinal no fragmento central foi submetido à osteossíntese com uso de haste bloqueada. Durante o processo, ocorreu uma fragmentação a partir da fissura, o que resultou na presença de dois fragmentos ósseos com uma grande porção de perda óssea entre os dois. Os fragmentos ósseos restantes do fragmento central foram morcelizados e aplicados no defeito para atuar com enxerto ósseo. Quinze dias após a cirurgia o paciente apresentou apoio normal e ausência de dor, e consolidação óssea ocorreu em 7 meses pós operatórios. Uma vez que a coleta de enxerto nos gatos resulta em pouca quantidade de osso, a morcelização do fragmento central foi vital para promover enxerto suficiente para cobrir o defeito ósseo. Os autores sugerem que o uso de enxerto cortical autólogo fresco morcelizado pode ser um adjuvante no tratamento de fraturas cominutivas em gatos, como um tratamento alternativo à terapia convencional.

Use of a morcellized fragment of bone as a bone graft in a femoral fracture repair / Uso de fragmento ósseo morcelizado como enxerto ósseo no reparo de fratura femoral

As one of the most frequent reasons for presentation at the orthopedic services in veterinary practice, long bone fractures need bone continuity for consolidation to take place. This case report has demonstrates the use of a morcellized fragment of bone as a bone graft in a femoral fracture with major bone loss. A mixed-breed adult cat with a segmental femoral fracture with a large longitudinal fissure in the central bone fragment was submitted to an interlocking nail osteosynthesis. During the procedure a fracture occurred along the fissure resulting in two bone fragments with significant bone loss. Fragments were morcellized and applied over the defect to act as a bone graft. By the 15th day after the surgery, the cat had a normal gait and showed no pain response, and bone consolidation occurred after 7 months. Once harvesting of humeral, femoral and tibial bone grafts can be frustrating in cats, resulting in just small amounts of bone, the morcellation of the central fragments was vital to provide sufficient graft to cover the big defect in the femoral shaft. The authors suggest that autologous fresh morcellized cortical bone fragments can be an adjunct to the treatment of comminuted fractures in cats, as an alternative to more traditional repairs of comminuted fracture.

Fraturas de ossos longos necessitam de continuidade óssea para que a consolidação ocorra. Este relato de caso tem como objetivo demonstrar o uso de um fragmento ósseo morcelizado com a função de enxerto ósseo em uma fratura de fêmur com presença de uma grande falha óssea entre os fragmentos. Um gato adulto, sem raça definida, com uma fratura múltipla em fêmur com presença de uma fissura longitudinal no fragmento central foi submetido à osteossíntese com uso de haste bloqueada. Durante o processo, ocorreu uma fragmentação a partir da fissura, o que resultou na presença de dois fragmentos ósseos com uma grande porção de perda óssea entre os dois. Os fragmentos ósseos restantes do fragmento central foram morcelizados e aplicados no defeito para atuar com enxerto ósseo. Quinze dias após a cirurgia o paciente apresentou apoio normal e ausência de dor, e consolidação óssea ocorreu em 7 meses pós operatórios. Uma vez que a coleta de enxerto nos gatos resulta em pouca quantidade de osso, a morcelização do fragmento central foi vital para promover enxerto suficiente para cobrir o defeito ósseo. Os autores sugerem que o uso de enxerto cortical autólogo fresco morcelizado pode ser um adjuvante no tratamento de fraturas cominutivas em gatos, como um tratamento alternativo à terapia convencional.

Sinus floor elevation using a new bovine bone grafting material: case report and bone grafting materials update / Actualización en materiales de relleno óseo: reporte de un caso clínico de elevamiento del piso del seno maxilar usando un nuevo material de relleno óseo bovino

Bone grafting is important to preserve the alveolar bone ridge height and volume for dental implant placement. Even though implant-supported overdentures present highly successful outcomes, it seems that a great number of edentulous individuals have not pursued implant-based rehabilitation. The cost of the treatment is one of the reasons of discrepancy between highly successful therapy and its acceptance. Therefore, the development of biomaterials for bone grafting with comparable characteristics and biological effects than those renowned internationally, is necessary. In addition, domestic manufacture would reduce the high costs in public health arising from the application of these biomaterials in the dental feld. The purpose of this clinical case report is to provide preliminary clinical evidence of the efficacy of a new bovine bone graft in the bone healing process when used for sinus floor elevation. (AU)

El uso de injertos óseos es importante para preservar la altura y el volumen de la cresta alveolar para la colocación de implantes dentales. Si bien las sobredentaduras implanto-soportadas presentan resultados altamente exitosos, la mayoría de las personas desdentadas no han sido rehabilitadas mediante implantes dentales. Uno de los principales motivos por los cuales los pacientes no aceptan este tipo de tratamiento, altamente exitoso, es el elevado costo del mismo. Por ello, es necesario el desarrollo de biomateriales de injerto óseo con características y efectos biológicos comparables a los reconocidos internacionalmente. Asimismo, la fabricación nacional reduciría los altos costos en Salud Pública derivados de la aplicación de estos biomateriales en el campo dental. El objetivo de esta comunicación es presentar un caso clínico a fin de proporcionar evidencia preliminar acerca de la eficacia de un nuevo injerto de hueso bovino en el proceso de cicatrización ósea en el levantamiento del piso del seno maxilar. (AU)

Natural bioceramics: our experience with changing perspectives in the reconstruction of maxillofacial skeleton

OBJECTIVES: Various bone graft substitute materials are used to enhance bone regeneration in the maxillofacial skeleton. In the recent past, synthetic graft materials have been produced using various synthetic and natural calcium precursors. Very recently, eggshell-derived hydroxyapatite (EHA) has been evaluated as a synthetic bone graft substitute. To assess bone regeneration using EHA in cystic and/or apicectomy defects of the jaws through clinical and radiographic evaluations. MATERIALS AND METHODS: A total of 20 patients were enrolled in the study protocol (CTRI/2014/12/005340) and were followed up at 4, 8, 12, and 24 weeks to assess the amount of osseous fill through digital radiographs/cone-beam computed tomography along with clinical parameters and complications. Wilcoxon matched pairs test, means, percentages and standard deviations were used for the statistical analysis. RESULTS: The sizes of the lesions in the study ranged from 1 to 4 cm and involved one to four teeth. The study showed significant changes in the formation of bone, the merging of material and the surgical site margins from the first week to the first month in all patients (age range, 15-50 years) irrespective of the size of the lesions and the number of teeth involved. Bone formation was statistically significant from the fourth to the eighth week, and the trabecular pattern was observed by the end of 12 weeks with uneventful wound healing. CONCLUSION: EHA showed enhancement of bone regeneration, and healing was complete by the end of 12 weeks with a trabecular pattern in all patients irrespective of the size of the lesion involved. The study showed enhancement of bone regeneration in the early bone formative stage within 12 weeks after grafting. EHA is cost effective and production is environment friendly with no disease transfer risks. Thus, natural bioceramics will play an important role in the reduction of costs involved in grafting and reconstruction.

Growth dynamic of allogeneic and autogenous bone grafts in a vertical model

Abstract Several techniques have been proposed for vertical bone regeneration, and many of them use bone autogenous and allogeneic grafts. The purpose of this study was to compare demineralised freeze-dried bone allografts (DFDBA), fresh-frozen (FF) allografts, autogenous bone grafts to find differences between volumetric and histological quantity of bone formation and vertical bone growth dynamic. A vertical tissue regeneration bone model was performed in rabbit calvarias under general anaesthesia. Four hollow cylinders of pure titanium were screwed onto external cortical bone calvarias in eight rabbits. Each one of the cylinders was randomly filled with one intervention: DFDBA, FF, autogenous bone, or left to be filled with blood clot (BC) as control. Allogeneic grafts were obtained from a ninth animal following international standardised protocols for the harvesting, processing, and cryopreservation of allografts. Autogenous graft was obtained from the host femur scraping before adapting hollow cylinders. Animals were euthanized at 13 weeks. Vertical volume was calculated after probe device measurements of the new formed tissue inside the cylinders and after titanium cylinders were removed. Histomorphometry and fluorochrome staining were used to analyse quantity and dynamic of bone formation, respectively. Results showed that DFDBA and fresh-frozen bone improved the velocity and the quantity of bone deposition in distant portions of the basal plane of grafting. Remaining material in allograft groups was more intense than in autogenous group. Both allografts can be indicated as reliable alternatives for volume gain and vertical bone augmentation.

Resumo Várias técnicas foram propostas para regeneração óssea vertical, e muitas delas usam enxertos ósseos e alogênicos ósseos. O objetivo deste estudo foi comparar os aloenxertos ósseos congelados desmineralizados (DFDBA), os aloenxertos congelados frescos (FF) com os enxertos ósseos autógenos para encontrar diferenças entre o volume, a histologia da formação óssea e a dinâmica do crescimento ósseo vertical. Um modelo ósseo de regeneração tecidual vertical foi realizado em calvarias de coelho sob anestesia geral. Quatro cilindros ocos de titânio puro foram parafusados nas calvarias de osso cortical externo em oito coelhos. Cada um dos cilindros foi preenchido aleatoriamente com uma intervenção: DFDBA, FF, osso autógeno ou com coágulo sanguíneo (BC) como controle. Os enxertos alogênicos foram obtidos a partir de um nono animal seguindo protocolos internacionais padronizados para a coleta, processamento e criopreservação de aloenxertos. O enxerto autógeno foi obtido da raspagem do fêmur do hospedeiro antes de adaptar os cilindros ocos. Os animais foram eutanasiados após 13 semanas. O volume vertical foi calculado após a medição, por meio de sonda milimetrada, do novo tecido formado dentro dos cilindros e após a remoção dos cilindros de titânio. Histomorfometria e coloração com fluorocromios foram utilizados para analisar a quantidade e a dinâmica da formação óssea. Os resultados mostraram que DFDBA e osso fresco congelado melhoraram a velocidade e a quantidade de deposição óssea em porções distantes do plano basal de enxerto. O material remanescente nos grupos de aloenxerto foi mais intenso do que em grupo autógeno. Ambos os aloenxertos podem ser indicados como alternativas confiáveis para ganho de volume e aumento ósseo vertical.

Preliminary study on the biocompatibility and osteoconductive properties of a new bovine bone graft / Estudio preliminar sobre las propiedades de biocompatibilidad y osteoconductividad de un nuevo injerto de hueso bovino

To prevent post-extraction resorption and preserve the integrity of the alveolar ridges, the placement of bone grafts at the time of extraction is recommended. Bovine bone grafts are biocompatibile and osteoconductive, allowing new bone apposition by osteoprogenitor cells. Although there are trademarks recognized internationally regarding bovine bone grafts, they are expensive and even difficult to acquire. Therefore, domestic industry development of high quality biomaterials will reduce the public health high costs in the dental field. Here, we evaluated and compared the effects of an Argentinean manufactured bovine bone graft (Synergy Bone Matrix) with a bovine bone graft recognized for its osteoconductive effects (Bio-Oss), on bone healing in an experimental model in rats. We created critical sized bone defects in rat tibiae and filled them with either one of the bovine bone grafts or control. Clinical responses, X-ray findings, bone mineral density, and histological parameters were evaluated. No abscess, encapsulation, suppuration or inflammation of lymphatic nodes were observed. Radiographically, all implants were amalgamated to the surrounding bony margins, suggesting proper healing. On the other hand, control tibiae exhibited no signs of recovery and remained either unfilled or showed fibrous tissue formation. No statistical differences were observed in BMC and BMD between tibiae filled with Synergy Bone Matrix or Bio-Oss. Histological analysis revealed particles of both bone grafts surrounded by laminar bone tissue indicating osteoconductivity, without any inflammatory sign. This preliminary study suggests that Synergy Bone Matrix, as well as Bio-Oss, present similar properties of biocompatibility and osteoconductivity. (AU)

Para prevenir la resorción post-exodoncia y preservar la integridad de los rebordes alveolares, se recomienda la colocación de injertos óseos en el momento de la extracción. Los injertos de hueso bovino son biocompatibles y osteoconductivos, permitiendo nueva aposición ósea por células osteoprogenitoras. Existen marcas internacionales de injertos de hueso bovino, pero resultan caros e incluso difíciles de adquirir. Por ello, la elaboración de biomateriales de alta calidad, nacionales, reduciría los altos costos de salud pública en odontología. En este estudio, se evaluaron y compararon los efectos de un injerto de hueso bovino fabricado en Argentina (Synergy Bone Matrix) versus un injerto de hueso bovino reconocido por sus efectos osteoconductivos (Bio-Oss), en el proceso de cicatrización ósea en un modelo experimental en ratas. Para ello, creamos un defecto óseo crítico en tibia de rata el cual se rellenó con uno de los injertos de hueso bovino o control. Se evaluó: respuesta clínica y radiográfica, densidad mineral ósea e histología. No se observaron abscesos, encapsulación, supuración o inflamación de los ganglios linfáticos. Radiográficamente, todos los implantes se integraron a los márgenes óseos circundantes, sugiriendo una cicatrización adecuada. Por el contrario, las tibias control no mostraron signos de recuperación con formación de tejido fibroso. No se observaron diferencias estadísticas en las BMC y BMD entre las tibias Synergy Bone Matrix o Bio-Oss. La histología reveló partículas de ambos injertos óseos rodeadas por tejido óseo laminar indicando osteoconductividad sin signos inflamatorios. Este estudio preliminar sugiere que Synergy Bone Matrix presenta propiedades similares de biocompatibilidad y osteoconductividad que Bio-Oss. (AU)

Hydroxyapatite-lignin composite as a metallic implant-bone tissue osseointegration improver: experimental study in dogs / Compósito de hidroxiapatita sintética e lignina como promotor de osseointegração entre implante metálico e tecido ósseo: estudo experimental em cães

The study aimed to evaluate biocompatibility, osteoconduction and osseointegration of a pasty composite of hydroxyapatite (20%) and lignin (80%) as a promoter of metal implant and bone tissue integration. An intramedullary Schanz pin was implanted in both tibias of fifteen bitches. In the left tibia, the pin was coated with the biomaterial at the time of surgery. Marrow cavity was also filled with the biomaterial. Right limb did not receive the biomaterial, then constituting the control group. Tibias were harvested from five animals at 8, 60 and 150 days after surgery; three of them were analyzed by histological and biomechanical assessment and the two remaining tibias by X-ray diffraction. Results showed that the biomaterial is biocompatible, with osteoconductivity and osseointegration properties. Histological analysis and diffractograms showed the presence of hydroxyapatite in samples in all periods, although the presence of organic material of low crystallinity was variable. There was no statistical difference in the forces required for removal of the biocompatibility, osteoconductivity and osseointegration, it was not able to promote a better intramedullary pin anchorage.

O trabalho objetivou avaliar a biocompatibilidade, a osteocondução e a osseointegração de um compósito pastoso de hidroxiapatita (20%) e lignina (80%) como promotor de integração entre implante metálico e tecido ósseo. Um pino intramedular de Schanz foi implantado em ambas as tíbias de quinze cadelas. Na tíbia esquerda, o pino foi coberto com o biomaterial no momento da cirurgia. A cavidade medular também foi preenchida com o biomaterial. O membro direito não recebeu o biomaterial, constituindo assim o grupo controle. As tíbias foram coletadas de cinco animais aos oito, 60 e 150 dias após a cirurgia, sendo três encaminhadas para avaliação histológica e biomecânica e as duas restantes, para difração de raios X. Os resultados revelaram biocompatibilidade do material, com propriedades de osteocondução e osseointegração. As análises histológicas e os difratogramas mostraram presença da hidroxiapatita no tecido em todos os períodos avaliados, embora a presença de material orgânico de baixa cristalinidade tenha sido variável. Não houve diferença estatística na força necessária para remoção do pino intramedular entre os tempos ou tratamentos. Embora o biomaterial tenha apresentado biocompatibilidade, osteocondutividade e osseointegração, ele não foi capaz de promover uma melhor ancoragem do pino intramedular.

Avaliação histométrica e histoquímica de vidro bioativo no processo de reparação óssea / Histométrica assessment and histochemistry of bioactive glass in the process of bone repair

Os enxertos de origem autógena são osteogênicos e possuem como vantagens a produção de tecido ósseo originário do próprio organismo. A sua limitação é a grande morbidade cirúrgica. O biovidro é uma cerâmica bioativa com disponibilidade ilimitada que leva a uma cirurgia com menor morbidade. O presente estudo teve como objetivo avaliar o biovidro teste durante o reparo ósseo e compará-lo com outros substitutos ósseos, em defeitos cirúrgicos experimentais em tíbia de ratos. O biovidro teste (CEELBIO, Belo Horizonte, Brasil), previamente caracterizado foi comparado com o Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA), através de espectroscopia na região do infravermelho, microscopia eletrônica de varredura (MEV), espectroscopia de dispersão em energia (EDS) e fluorescência de Rx. Após as análises estruturais, deu-se início ao estudo in vivo. Foram utilizados 120 ratos (rattus norvegicus albinus, Wistar) machos, com aproximadamente 7 a 8 semanas. Os defeitos ósseos foram realizados na tíbia direita dos animais e preenchidos de acordo com a seguinte divisão: Grupo I- controle negativo, sem preenchimento; Grupo II- foi preenchido por Biogran®; Grupo III- preenchido por biovidro teste; Grupo IVcontrole positivo, com preenchimento com osso autógeno. Nos períodos de 7, 14, 21, 28, 49 e 70 dias pós-operatório, os animais foram eutanasiados e os processos de mineralização óssea e reparo foram analisados através de histomorfometria (% de osso neoformado no sítio do defeito). Níveis de BMP-2 foram mensurados através de ensaio de ELISA. Análise estatística foi realizada utilizando programa SPSS (versão 20.0, SPSS Inc., Chicago, USA). Os resultados da análise histológica demonstraram que, no controle negativo, houve neoformação óssea até os 14 dias (20,40%, p<0,001) e depois houve reabsorção em até 21 dias (6,60%, p<0,001). No grupo de Biogran®, houve uma neoformação óssea junto aos grãos em 7 dias (34,20%, p= 0,019) e que se manteve enquanto o material estava presente nos defeitos em 70 dias (15,67%, p= 0,048). O biovidro teste foi reabsorvido totalmente até 21 dias e os picos de osso neoformado foram observados em 7 (21,00%, p= 0,019) e 49 dias (15,60%, p= 0,036). Nesse grupo, células semelhantes a macrófagos, dispostas em lençol, foram visualizadas junto a tecido ósseo neoformado. Quanto ao controle positivo, o osso autógeno foi totalmente reabsorvido em até 14 dias e o pico de formação óssea se deu nesse 9 mesmo momento, em 14 dias, (40,80%, p<0,001), mostrando-se, nos tempos subsequentes, similar ao controle negativo. Células gigantes multinucleadas foram encontradas em áreas de remodelação óssea, junto ao Biogran® e ao biovidro teste. Os níveis de BMP-2 no grupo controle negativo se mostraram maiores nos tempos de 7 (418,80pg/mL, p= 0,871) e 28 dias (346,36 pg/mL, p= 0,035). No grupo Biogran® o pico de BMP-2 se deu em 7 dias (471,95 pg/mL, p= 0,871). O biovidro teste teve seu pico de liberação de BMP-2 em 7 dias também (471,39 pg/mL, p= 0,871). Já o controle positivo apresentou nível de BMP-2 em maior quantidade nos tempos de 7 (346,55 pg/mL, p= 0,871) e 21 dias (407,57 pg/mL, p= 0,300). O biovidro é um material degradável, e com características biológicas de osteoindução e osteocondução

The autogenous origin grafts are osteogenic and have the advantage of producing bone tissue originated from the body itself. Its limitation is the great surgical morbidity. The bioglass is a bioactive ceramic with unlimited availability that leads to a surgery with less morbidity. This study aimed to evaluate the bioglass test during bone repair and to compare it with other bone substitutes in experimental surgical defects in the tibia of rats. The bioglass test (CEELBIO, Belo Horizonte, Brazil), has been characterized and compared to the Biogran® (Biomet 3i Inovattions Inc., Palm Beach Gardens, USA) by spectroscopy in the infrared, scanning electron microscopy (SEM), EDS spectroscopy and Rx fluorescence. The study in vivo has been started after the structural analysis. 120 rats (Rattus norvegicus albinus, Wistar rats), with approximately 7 to 8 weeks, were used. The bone defects were performed in the right tibia of animals and filled according to the following breakdown: Group I- negative control without filling; Group II- filled by Biogran®; Group III- filled with bioglass test; IV- positive control group, with filling of autogenous bone. At 7, 14, 21, 28, 49 and 70 postoperative days, the animals were euthanized and bone mineralization processes and repair were analyzed by histomorphometry (% of newly formed bone in the defect site). BMP-2 levels were measured by ELISA assay. Statistical analysis was performed using SPSS (version 20.0, SPSS Inc., Chicago, USA). The results of the histological analysis showed that in the negative control there was no bone growth up to 14 days (20.40%, p <0.001) and after reabsorption, within 21 days (6.60%, p <0.001). In Biogran® group, there was new bone formation along the grain in 7 days (34.20%, p = 0.019) and that was maintained as the material was present in shortcomings in 70 days (15.67%, p = 0.048) . The test bioglass was completely reabsorbed within 21 days; new bone formation and peaks were observed in 7 (21.00%, p = 0.019) and 49 days (15.60%, p = 0.036). In this group, macrophage-like cells arranged in sheets, were viewed with the newly formed bone. On the positive control, autologous bone was completely reabsorbed within 14 days, and the peak bone formation occurred at the same moment, within 14 days (40.80%, p <0.001), showing, in subsequent occasions, similar to control negative. Multinucleated giant cells were found in areas of bone remodeling, with the Biogran® and test bioglass. BMP-2 levels in the negative control group were higher in 7 (418,80pg / ml, p = 11 0.871) and 28 days (346.36 pg / ml, p = 0.035). In Biogran® group peak BMP-2 occurred within 7 days (471.95 pg / ml, p = 0.871). The test bioglass had its peak BMP-2 release in 7 days as well (471.39 pg / ml, p = 0.871). The positive control showed BMP-2 level in greater quantities in 7 (346.55 pg / ml, p = 0.871) and 21 days (407.57 pg / ml, p = 0.300). The test bioglass is a biodegradable material, with biological characteristics of osteoinduction and osteoconduction

NanoSynt: avaliação histológica e histomorfométrica de um novo substituto ósseo. O uso da nanotecnologia na conquista de um melhor padrão de osteocondução / NanoSynt: histological and histomorphometric analyses of a new bone substitute. The use of nanotechnology towards a better osteoconductive pattern

Objetivo: apresentar os resultados histológicos e histomorfométricos do uso de três substitutos ósseos disponíveis comercialmente, com relação à sua capacidade de regeneração óssea. Material e métodos: foram utilizados três biomateriais para preenchimento de defeitos críticos na calvária de coelhos, e mantidos por quatro e oito semanas in vivo. Resultados: do ponto de vista morfológico, um padrão de cicatrização semelhante foi observado para os três diferentes materiais, em que a formação do osso foi observada a partir das margens para o centro do defeito, nos tempos decorridos in vivo. De um ponto de vista quantitativo, o material NanoSynt apresentou maiores níveis médio de formação óssea, quantidade de biomaterial e de manutenção de espaço do defeito in vivo, quando comparado aos outros dois biomateriais. Conclusão: todos os substitutos ósseos utilizados apresentaram características de biocompatibilidade, não interferindo negativamente no processo de reparo. Entretanto, o biomaterial sintético NanoSynt apresentou maior nível de formação óssea e manutenção do espaço do defeito, quando comparado aos materiais Boneceramic e Bio-Oss durante os dois períodos in vivo do presente estudo (quatro e oito semanas).

Objective: to present the histological and histomorphometric results on the use of three commercially available bone substitutes with respect to its capacity of bone regeneration. Material and methods: three biomaterials were used to fill critical defects in the calvaria of rabbits kept 4 and 8 weeks in vivo. Results: from the morphological point of view, a similar pattern of healing was observed for three different materials, in which bone formation was observed from the margins to the center of the deffect, according to evaluated periods. From a quantitative point of view, the NanoSynt material exhibited higher mean levels of bone formation, amount of biomaterial, and space maintenance defect in vivo when compared to the other two biomaterials. Conclusion: all bone substitutes used showed biocompatibility and does not interfere negatively in the repair process. However, the synthetic biomaterial NanoSynt showed higher levels of bone formation and maintenance of the area of the defect when compared to materials BoneCeramic and Bio-Oss during the two periods in vivo in the present study (4 and 8 weeks).

Role of tricalcium phosphate implant in bridging the large osteoperiosteal gaps in rabbits.

Treatment options for large osteoperiosteal defects are limited and that which are available are not ideal. Osteoperiosteal defect were created in ulnae of both forelimbs of rabbits and tricalcium phosphate implant was used to bridge the gap. Amongst the 35 implanted ulnae, one implant got dislodged. Rest of the implants showed good adherence to host bone until the final follow up. Five control rabbit limbs (in which no implants were put) showed persistent bone gap. Histological and Electron microscopic examination revealed bone tissues covering the surface of the implant and bridging the gap. New bone was formed in the pores also. Tricalcium phosphate implants showed new bone formation due to osteoconductive properties. They are biodegradable. It is suggested that tricalcium phosphate implants are viable treatment alternatives in management of large osteoperiosteal defects with minimal to no adverse effects.

Análise da utilização do osteoscafTM como substituto ósseo em cirurgia de levantamento de seio maxilar / Use of OsteoScaf™ in maxillary sinus augmentation

Procedimentos de levantamento do seio maxilar têm sido realizados para aumentar o volume ósseo e promover a estabilidade do implante, na região posterior de maxilas severamente atrofiadas. Ao longo dos anos, resultados de vários estudos demonstraram que alguns substitutos ósseos podem suportar implantes em função, após o levantamento de seio maxilar, igual ou melhor quando utilizado o osso autógeno. Neste estudo, foi avaliado o comportamento de um substituto ósseo completamente biodegradável (OsteoScaf™) no modelo experimental de levantamento de seio maxilar em coelhos. Além disso, ele foi comparado com o osso autógeno e outros dois substitutos ósseos, não totalmente biodegradáveis, disponíveis comercialmente (Bio-Oss® e BoneCeramic®). Avaliação clínica, tomografia computadorizada por feixe cônico, microtomografia computadorizada, análises microscópicas e análise molecular, através da técnica de PCR, foram realizadas após 2, 4 e 8 semanas de cirurgia. O levantamento de seio maxilar utilizando o osso autógeno demonstrou maior reabsorção, ao longo do tempo, comparado aos substitutos ósseos, os quais revelaram maior neoformação óssea após 8, 4 e 2 semanas, respectivamente. O grupo Bio-Oss® apresentou maior neoformação óssea, ao longo do tempo, quando comparado aos grupos Osteoscaf™ e BoneCeramic®, os quais foram qualitativamente emelhantes. O grupo BoneCeramic® mostrou uma resposta celular de células gigantes até 8 semanas. Concluiu-se que os substitutos ósseos, neste estudo, obtiveram melhor desempenho do que o osso autógeno, e o OsteoScaf™ demonstrou maior reabsorção do que os outros grupos, em todos períodos.

Maxillary sinus augmentation procedures have been applied to increase bone volume and to promote stability of implants in the severely atrophied posterior maxilla. Over the years, the outcomes of several studies have demonstrated that some bone substitutes can support implants in function after sinus augmentation as well as, or better than those with autogenous bone. Our experimental model evaluated the behavior of a fully biodegradable bone substitute (OsteoScaf™) in a rabbit sinus lift procedure. We compared this with autogenous bone and other two available non-biodegradable bone substitutes (Bio-Oss® and BoneCeramic®). Clinical evaluation, Cone Beam Computed Tomography, Microcomputed Tomography, microscopic and molecular evaluation were used for data analysis at 2, 4 and 8 weeks after sinus augmentation. Autogenous bone was more resorbed over time than the other materials. All bone substitutes showed more bone formation at 8, 4 and 2 weeks, respectively. Bio-Oss® showed more bone formation/timepoint than Osteoscaf™ and Boneceramic®, which were similar. Boneceramic® showed a florid giant cell response up to 8 weeks. We concluded that the bone graft materials all performed better than autogenous bone and OsteoScaf™ showed comparative bone growth yet greater degradation than the other two materials.

Histomorphometric Analysis on Bone Formation Effect of Beta-tricalciumphosphate around Dental Implants in Rabbit Mandibular Body: Pilot Study

Análise da utilização do osteoscafTM como substituto ósseo em cirurgia de levantamento de seio maxilar / Use of OsteoScaf™ in maxillary sinus augmentation

Procedimentos de levantamento do seio maxilar têm sido realizados para aumentar o volume ósseo e promover a estabilidade do implante, na região posterior de maxilas severamente atrofiadas. Ao longo dos anos, resultados de vários estudos demonstraram que alguns substitutos ósseos podem suportar implantes em função, após o levantamento de seio maxilar, igual ou melhor quando utilizado o osso autógeno. Neste estudo, foi avaliado o comportamento de um substituto ósseo completamente biodegradável (OsteoScaf™) no modelo experimental de levantamento de seio maxilar em coelhos. Além disso, ele foi comparado com o osso autógeno e outros dois substitutos ósseos, não totalmente biodegradáveis, disponíveis comercialmente (Bio-Oss® e BoneCeramic®). Avaliação clínica, tomografia computadorizada por feixe cônico, microtomografia computadorizada, análises microscópicas e análise molecular, através da técnica de PCR, foram realizadas após 2, 4 e 8 semanas de cirurgia. O levantamento de seio maxilar utilizando o osso autógeno demonstrou maior reabsorção, ao longo do tempo, comparado aos substitutos ósseos, os quais revelaram maior neoformação óssea após 8, 4 e 2 semanas, respectivamente. O grupo Bio-Oss® apresentou maior neoformação óssea, ao longo do tempo, quando comparado aos grupos Osteoscaf™ e BoneCeramic®, os quais foram qualitativamente emelhantes. O grupo BoneCeramic® mostrou uma resposta celular de células gigantes até 8 semanas. Concluiu-se que os substitutos ósseos, neste estudo, obtiveram melhor desempenho do que o osso autógeno, e o OsteoScaf™ demonstrou maior reabsorção do que os outros grupos, em todos períodos.

Maxillary sinus augmentation procedures have been applied to increase bone volume and to promote stability of implants in the severely atrophied posterior maxilla. Over the years, the outcomes of several studies have demonstrated that some bone substitutes can support implants in function after sinus augmentation as well as, or better than those with autogenous bone. Our experimental model evaluated the behavior of a fully biodegradable bone substitute (OsteoScaf™) in a rabbit sinus lift procedure. We compared this with autogenous bone and other two available non-biodegradable bone substitutes (Bio-Oss® and BoneCeramic®). Clinical evaluation, Cone Beam Computed Tomography, Microcomputed Tomography, microscopic and molecular evaluation were used for data analysis at 2, 4 and 8 weeks after sinus augmentation. Autogenous bone was more resorbed over time than the other materials. All bone substitutes showed more bone formation at 8, 4 and 2 weeks, respectively. Bio-Oss® showed more bone formation/timepoint than Osteoscaf™ and Boneceramic®, which were similar. Boneceramic® showed a florid giant cell response up to 8 weeks. We concluded that the bone graft materials all performed better than autogenous bone and OsteoScaf™ showed comparative bone growth yet greater degradation than the other two materials.

Three-year Follow-up after Autogenous and Xenogenic Jaw Bone Grafts

Clinical application of auto-tooth bone graft material

INTRODUCTION: Auto-tooth bone graft material consists of 55% inorganic hydroxyapatite (HA) and 45% organic substances. Inorganic HA possesses properties of bone in terms of the combining and dissociating of calcium and phosphate. The organic substances include bone morphogenetic protein and proteins which have osteoinduction capacity, as well as the type I collagen identical to that found in alveolar bone. Auto-tooth bone graft material is useful as it supports excellent bone regeneration capacity and minimizes the possibility of foreign body reaction,genetic diseases and disease transmission. MATERIALS AND METHODS: Implant placement combined with osteoinductive regeneration,preservation of extraction socket, maxillary sinus augmentation, and ridge augmentation using block type,powder type, and block+powder type autobone graft materialwere performed for 250 patients with alveolar bone defect and who visited the Department of Oral and Maxillofacial Surgery, College of Dentistry, Dankook University from September 2009 to August 2011. RESULTS: Clinical assessment: Among the 250 patients of auto-tooth bone graft, clinical assessment was performed for 133 cases of implant placement. The average initial stabilization of placed implants was 74 implant stability quotient (ISQ). Radiological assessment: The average loss of crestal bone in the mandible as measured 6 months on the average after the application of prosthesis load was 0.29 mm, ranging from 0 mm to 3.0 mm. Histological assessment: In the histological assessment, formation of new bone, densified lamellated bone, trabecular bones, osteoblast, and planting fixtures were investigated. CONCLUSION: Based on these results, we concluded that auto-tooth bone graft material should be researched further as a good bone graft material with osteoconduction and osteoinduction capacities to replace autogenous bone, which has many limitations.

Osteoconductive and osseointegration properties of a commercial hydroxyapatite compared to a synthetic product / Comparación de las propiedades de osteoconducción y osteointegración de una hidroxiapatita reabsorbible comercial con una hidroxiapatita reabsorbible sintetizada / Comparação das propriedades da osteocondução e osteointegração de uma hidroxiapatita reabsorvivel comercial sintetizada

The effects of two types of hydroxylapatite on bone synthesis and properties were evaluated. An osteoconductive resorbable hydroxyapatite (OseoU), synthesized at two different temperatures of calcination (Type A and Type B) was compared with a commercial mixture of hydroxyapatite (Osteogen®), commonly used in several surgical procedures involving bone loss. The synthesis was performed in the laboratories of the University of Antioquia by precipitating a mixture of calcium nitrate and ammonium phosphate. The products obtained and the commercial hydroxyapatite were characterized by scanning electron microscopy (SEM), X- ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and energy dispersive spectroscopy (EDS). Osteoconductive and osseointegration characteristics were measured according to the products ability to induce local cell differentiation into bone forming cells. These characteristics were evaluated in hydroxyapatite implants performed in 70 New Zealand breed rabbits distributed into seven groups of 10 animals each, tested at 7, 14, 21, 28, 42, 60 and 90 days after the surgical procedure.

En el presente artículo se evalúan las propiedades de osteoconducción y osteointegración de una hidroxiapatita reabsorbible (OseoU), procesada a dos temperaturas diferentes de calcinación (Tipo A y Tipo B), con el propósito de compararlas con un preparado comercial de hidroxiapatita (Osteogen®), utilizado para múltiples procedimientos quirúrgicos en los cuales se involucra la pérdida de tejido óseo. La síntesis se realizó en los laboratorios de la Universidad de Antioquia por el método de precipitación acuosa de la mezcla de nitrato de calcio y de fosfato de amonio. Los productos obtenidos y la hidroxiapatita comercial fueron caracterizados por microscopia electrónica de barrido (SEM), difracción de rayos X (DRX), espectroscopia de infrarrojo transformada de Fourier (FTIR) y espectrometría por energía dispersiva (EDS). Las características de osteoconducción y osteointegración fueron medidas de acuerdo a la capacidad de los productos para inducir la diferenciación de células locales a células formadoras de hueso. Dichas características, se evaluaron en implantes de hidroxiapatita realizados en 70 conejos de la raza Nueva Zelanda distribuidos en siete grupos de 10 animales cada uno, evaluados a los 7, 14, 21, 28, 42, 60 y 90 días de efectuado el procedimiento quirúrgico. Los resultados obtenidos demostraron que el OseoU y el Osteogen®, presentaron características similares en cuanto a la estructura cristalina, la composición química y la adsorción, con apreciables diferencias morfológicas con respecto a la forma de las partículas. Al realizar el análisis de varianza no se encontraron diferencias estadísticas significativas para las variables histopatológicas evaluadas en las dos hidroxiapatitas (p>0.05), indicando que las hidroxiapatitas sintetizadas en la Universidad de Antioquia (OseoU) tuvieron el mismo resultado que la hidroxiapatita comercial (Osteogen®) en la osteoconducción y la osteointegración del tejido óseo.

No presente estudo foram avaliadas as propriedades de ostecondução e osteointegração de uma hidroxiapatita reabsorvivel (OseoU), processada a duas temperaturas de calcinaçao (Tipo A e B), com o propósito de serem comparadas com um produto comercial (Osteogen®), utilizado para múltiples procedimentos cirúrgicos nos quais se envolve a perda do tecido osso. Asíntese foi realizada nos laboratorios da Universidad de Antioquia pelo método de precipitação aquosa da mistura de nitrato de cálcio e fosfato de amônio. Os produtos obtidos e a hidroxiapatita comercial foram caracterizados por microscopia eletrônica de barrido (SEM), difração raios X (DRX), espectroscopia de infravermelho transformada de Fourier (FTIR) e espectrometria por energia dispersiva (EDS). As características de osteocondução e osteointegração foram mensuradas de acordo à capacidade dos produtos para induzir a diferenciação das células locais formadoras do osso. Estas características foram avaliadas em implantações de hidroxiapatita realizadas em 70 coelhos da raça Nova Zelândia distribuídos em sete grupos de 10 animais cada um, avaliados aos 7, 14, 21, 28, 42, 60 e 90 dias de efetuado o procedimento cirúrgico. Os resultados obtidos demonstraram que o OseoU e o Osteogen® apresentaram características similares em quanto à estrutura cristalina, a comparação química e à absorção, com apreciáveis diferenças morfológicas com respeito à forma das partículas. Ao realizar as análises de variâncias não foram encontradas diferencias estatísticas significativas para as variáveis histopatológicas avaliadas nas duas hidroxiapatitas (p>0.05), indicando que as hidroxiapatitas sintetizadas na Universidad de Antioquia (OseoU) tiveram o mesmo resultado que a hidroxiapatita comercial (Osteogen®) em osteocondução e osteointegração do tecido ósseo.

Morphometric analysis on bone formation effect of beta-TCP and rhBMP-2 in rabbit mandible

INTRODUCTION: This study was to assess the effectiveness of new bone formation and regeneration by using a rhBMP-2 and beta-TCP as a carrier in rabbits' mandible. MATERIALS AND METHODS: The mandibles of 36 rabbits were exposed and cortical bone was penetrated for this study. The experimental subjects were divided into 3 groups each 12 rabbits; control group, experimental group 1, and experimental group 2. Control group had the defect itself without any treatment, in the experimental group 1, beta-TCP only was grafted, and in the experimental group 2, rhBMP-2 soaked in beta-TCP was grafted. The rabbits were sacrificed after 1, 2, 3, 4, 6, and 8weeks, and new bone formation area was examined and measured for bone quantitative and qualitative analysis with light, fluorescent and polarized microscopy. RESULTS: In the experimental group 1, new bone formation from the adjacent host bone was made by osteoconduction, and in the experimental group 2, direct new bone formation by osteoinduction of rhBMP-2 as well as new bone formation by osteoconduction of beta-TCP were observed. CONCLUSION: rhBMP-2 of experimental group 2 is very effective in the bone formation in early 2weeks and bone remodelling from 3weeks.

A study about early osteoconductivity of porous alloplastic carbonapatite and anorganic bovine xenograft in canine maixlliary augmentation model

Effects of Polyphosphate on the Fusion of Rabbit Lumbar Spine / 대한척추외과학회지

STUDY DESIGN: Posterior and posterolateral fusions were performed in rabbit lumbar spines. OBJECTIVES: To investigate the osteoinductive effect of polyphosphates. SUMMARY AND LITERATURE REVIEW: Inorganic polyphosphates are known to be rich in osteoblasts and involved in the mineralization process in bone metabolism. However, no study has been undertaken to investigate the osteoinductive effect of polyphosphates. MATERIALS AND METHODS: Forty adult New Zealand white rabbits underwent monolevel lumbar fusions, and were divided into two groups according to the fusion beds: twenty each between the laminae (posterior fusion group, PF group) and between the transverse processes (posterolateral fusion group, PLF group). In ten of twenty rabbits in the PF group, 0.8gm of autogenous iliac bone was grafted onto the right sides of the laminae, which were used as a control group (C1), with 0.4gm autogenous bone immersed in polyphosphate solution in the left sides as an experimental group (E1). In the other ten, 0.8gm of autogenous bone was grafted onto the right sides (C2) and 0.8gm of tricalcium phosphate porous blocks containing polyphosphate in the left sides (E2). The other twenty rabbits of the PLF group were similarly divided into C1, E1, C2 and E2 groups by grafting the same amount of materials between the transverse processes. The animals were sacrificed at the 16th postoperative week and the fusions evaluated grossly, radiologically and histologically. Statistical differences between the groups (C1 vs. E1, C2 vs. E2 and E1 vs. E2) in each of the PF and PLF groups were compared by chi-square tests. RESULTS: The fusions were finally determined by the gross finding using manual palpation. In the PF group, bony fusions were obtained in 90, 80, 90 and 70% of the C1, E1, C2 and E2 groups, respectively. In the PLF group, these were 80, 70, 60 and 0% of the C1, E1, C2 and E2 groups, respectively. Statistical analysis revealed differences only between C2 and E2 (p=0.005), and between E1 and E2 (p=0.002) of the PLF group. Histologically, beta-tricalcium phosphate particles containing polyphosphate were transformed into the osteoid in some areas of the PLF-E2 group, although only fibrous unions were obtained grossly. CONCLUSIONS: It is suggested that the polyphosphate may have an osteoinductive effect, even though the osteoinductive potency was very week in this fusion model of the rabbit lumbar spine. Therefore, further explorations, such as the threshold and optimal concentrations of polyphosphate in vivo and the best carrier material of polyphosphate, should be performed to obtain the optimal conditions for fusion.