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1.
Braz. dent. j ; 32(1): 26-33, Jan.-Feb. 2021. graf
Article in English | LILACS, BBO | ID: biblio-1180720

ABSTRACT

Abstract The limited options for bone repair have led to an extensive research of the field and the development of alloplastic and xenogeneic grafts. The purpose of this study was to evaluate bone repair with two bone substitutes: deproteinized bovine bone (DBB) and biphasic calcium phosphate ceramic (BCP) in critical-size defect. A total of 8-mm defects were made in the parietal bones of rabbits (n=12). The animals were divided into three experimental groups: sham (defect filled with a blood clot), DBB (defect filled with DBB), and BCP (defect filled with BCP). After the experimental periods of 15 and 45 days, the animals were euthanized and submitted to histomorphometric analysis. The total defect area, mineralized tissue area, biomaterial area, and soft tissue area were evaluated. A greater amount of immature bone tissue and biomaterial particles were observed in the BCP group compared to DBB and sham at 45 days (p<0.05). There was no difference in the qualitative pattern of bone deposition between DBB and BCP. However, the sham group did not show osteoid islands along with the defect, presenting a greater amount of collagen fibers as well in relation to the DBB and BCP groups. There was a greater number of inflammatory cells in the DBB at 45 days compared to BCP and sham groups. In conclusion, BCP and DBB are options for optimizing the use of bone grafts for maxillofacial rehabilitation. Bone defects treated with BCP showed greater deposition of bone tissue at 45 days.


Resumo As opções limitadas para reparo ósseo levaram ao desenvolvimento de abrangente pesquisa na área de enxertos aloplásticos e xenogênicos. O objetivo deste estudo foi avaliar o reparo ósseo com dois substitutos ósseos: osso bovino desproteinizado (DBB) e cerâmica fosfática de cálcio bifásica (BCP) em defeito de tamanho crítico. Material e métodos: defeitos críticos de 8 mm foram feitos nos ossos parietais de coelhos (n=12). Os animais foram divididos em três grupos experimentais: sham (defeito preenchido com coágulo sanguíneo), DBB (defeito preenchido com DBB) e BCP (defeito preenchido com BCP). Após os períodos experimentais de 15 e 45 dias, os animais foram sacrificados e submetidos à análise histomorfométrica. Foram avaliadas a área total de defeitos, área de tecidos mineralizados, área de biomateriais e área de tecidos moles. Resultados: maior quantidade de tecido ósseo imaturo e de partículas de biomaterial foram observados no grupo BCP em comparação aos grupos DBB e sham aos 45 dias (p<0,05). Não houve diferença no padrão qualitativo de deposição óssea entre DBB e BCP. Ainda, o grupo sham não apresentou ilhas osteóides ao longo do defeito, apresentando maior quantidade de fibras colágenas em relação aos grupos DBB e BCP. Houve maior quantidade de células inflamatórias no DBB aos 45 dias em comparação aos grupos BCP e sham. Conclusões: BCP e DBB são opções para otimizar o uso de enxertos ósseos na reabilitação de pacientes. Defeitos ósseos tratados com BCP mostraram maior deposição de tecido ósseo aos 45 dias.


Subject(s)
Animals , Rabbits , Bone Substitutes , Hydroxyapatites , Osteogenesis , Bone Matrix , Bone Regeneration , Calcium Phosphates , Cattle , Ceramics
2.
Int. j. morphol ; 38(5): 1426-1433, oct. 2020. graf
Article in English | LILACS | ID: biblio-1134459

ABSTRACT

SUMMARY: Bone morphogenetic protein (rhBMP-2) is a powerful osteo-inductive growth factor widely used in bone reconstruction and both the vehicle used to administer it and the scaffold substrate could determine its success in clinical situations. The aim was to analyse the clinical behaviour of dental implants placed in single alveolar ridges with a horizontal deficiency in the maxillary anterior region that were reconstructed horizontally with rhBMP-2 and porous hydroxyapatite (HA). Inclusion criteria were both males and females, between the ages of 18 and 29 with single tooth loss of one upper incisor. Cone Beam Computed Tomography (CBCT) was used to take measurements prior to bone augmentation and again prior to the implant insertion. Surgery was carried out under local anaesthetic. In the primary procedure, bone substitute was introduced using porous HA and rhBMP-2; after 4 to 5 months, dental implant surgery was carried out and the implant placed; after 3 months of consolidation the provisional prosthesis was placed and then a definitive restoration was placed. Variables were analysed using the t-test with a p-value of < 0.05 in order to assess statistical significance. Thirteen subjects were included (6 females and 7 males). Bone augmentation resulted in a bone gain of 4.15mm (p=0.023), which was shown to be statistically significant. All of the grafts placed were successful and 13 implants were placed, using torques between 30 and 70N, without complications. For the final prostheses, 11 were screw retained and 2 were cemented in place. The horizontal bone augmentation using HA and rhBMP-2 is an efficient technique for single bone defects in the anterior maxillary area; clinical trials on a larger scale are needed to confirm these results.


RESUMEN: La proteína ósea morfogenética (BMP-2) es un potente osteoinductor utilizado ampliamente en técnicas reconstructivas; el vehículo de instalación es determinante en su evolución. El objetivo fue analizar el comportamiento clínico de implantes dentales instalados en rebordes alveolares únicos con deficiencia horizontal del sector anterior reconstruida horizontalmente con BMP-2 e hidroxiapatita (HA) porosa. Fueron incluidos sujetos de ambos sexos de entre 18 y 29 años, con pérdida dentaria unitaria a nivel de incisivos superiores. Se utilizó tomografía computadorizada para realizar mediciones en las etapas previa a la instalación del injerto y previo a la instalación del implante. Las cirugías fueron realizadas bajo anestesia local. En la primera intervención se realizó la instalación del injerto óseo utilizando HA porosa y BMP-2; después de 4 a 5 meses se realizó la instalación del implante dental; 3 meses después se realizó la conexión protésica y rehabilitación final. Las variables fueron estudiadas con la prueba t test considerando el valor de p< 0,05 para considerar significancia estadística. Trece sujetos fueron incluidos (6 mujeres y 7 hombres); con la reconstrucción ósea se obtuvo una ganancia ósea de 4,15mm (p=0.023) que fue estadísticamente significativo. No existió pérdida en ningún injerto realizado; se instalaron 13 implantes con torques entre 30 y 70N sin complicaciones; se realizaron prótesis fijas atornilladas en 11 casos y cementadas en 2 casos. La técnica con HA y BMP- 2 es eficiente para reconstruir defectos horizontales en perdidas unitarias del sector anterior maxilar; ensayos clínicos de mayor escala son necesarios para confirmar estos resultados.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Young Adult , Bone Morphogenetic Protein 2/therapeutic use , Alveolar Ridge Augmentation/methods , Hydroxyapatites/therapeutic use , Maxilla/surgery , Bone Regeneration , Tomography, X-Ray Computed , Dental Implants , Longitudinal Studies , Bone Transplantation/methods , Bone Substitutes , Alveolar Process/diagnostic imaging , Maxilla/diagnostic imaging
3.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 79-86, Jan.-Feb. 2020. tab, ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1088942

ABSTRACT

Dos atendimentos ortopédicos realizados em aves no HCV-UFRGS, 86% são fraturas, sendo aproximadamente 30% delas cominutivas com perda óssea expressiva, justificando a importância da utilização de enxertos em fraturas de aves. O objetivo deste trabalho foi avaliar dois aloenxertos e enxerto sintético de hidroxiapatita em defeito ósseo de galinhas. Utilizaram-se 30 galinhas separadas em três grupos: aloenxerto congelado em ultra-freezer (GUF), aloenxerto congelado em nitrogênio líquido (GNL) e enxerto sintético de hidroxiapatita deficiente em cálcio (GHA). Nos três grupos, os enxertos foram aplicados com placas e parafusos bloqueados de 2mm na ulna direita das aves, avaliando-se a evolução por meio de exames radiográficos até serem completados 90 dias de pós-operatório e o resultado final mediante exame histológico. A média e desvio-padrão relacionando o tempo de consolidação óssea radiográfica foi: GNL 61,67±21,79 dias (90% de consolidação), GUF 47,14±13,50 dias (70% de consolidação) e GHA 70±18,17 dias (60% de consolidação). Houve diferença significativa no tempo de consolidação óssea entre o GUF e o GHA. Histologicamente, os enxertos do GUF foram os que estavam em consolidação mais avançada. Os aloenxertos do GNL foram superiores no preenchimento de falha óssea ulnar de galinhas.(AU)


Of the orthopedic visits performed on birds at HCV-UFRGS, 86% are fractures, and approximately 30% of them are comminuted with expressive bone loss, justifying the importance of the use of grafts in bird fractures. The objective of this work was to test two allografts and a synthetic HADC graft on finishing in Gallus gallus domesticus. 30 laying hens were used, divided in three groups: frozen allograft in ultrafreezer (UFG); frozen allograft in liquid nitrogen (LNG); calcium deficient synthetic hydroxyapatite graft (HAG). The three graft groups were exposed to serial radiographs until the 90 postoperative days, as well as the histological examination at the end of the experiment were: LNG 61.67±21.79 days (90% consolidation), UFG 47.14±13.50 days (70% consolidation) and HAG 70±18.17 days (60% consolidation). There was a significant difference in bone healing time between GUF and GHA. Histologically, GUF grafts were the ones that were in the most advanced consolidation. LNG allografts were superior in filling ulnar bone failure of fowl.(AU)


Subject(s)
Animals , Ulna Fractures/diagnostic imaging , Chickens/surgery , Bone Transplantation/veterinary , Allografts , Hydroxyapatites/therapeutic use
4.
Belo Horizonte; s.n; 2020. 146 p. ilus, tab.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1223495

ABSTRACT

A incorporação de íons na estrutura da hidroxiapatita (HA) pode afetar sua estrutura, cristalinidade, solubilidade e citotoxicidade. Dentre os íons presentes na composição da apatita óssea, o magnésio (Mg2+), estrôncio (Sr2+) e zinco (Zn2+) são reconhecidos por promover a angiogênese e osteogênese. Portanto, as HAs substituídas podem apresentar melhor bioatividade, por fornecer íons com potencial de estimular a neoformação óssea nos locais enxertados. Nesse contexto, este estudo descreve a síntese, caracterização e comparação de uma série de nano-hidroxiapatitas (nHAs) substituídas e co-substituídas por Sr2+, Mg2+ ou Zn2+. Em seguida, foi desenvolvido um cimento ósseo à base das HAs com melhores resultados de citotoxicidade, associado ao DCPA, gelatina e quitosana. As nHAs foram caracterizadas físico-quimicamente usando diferentes técnicas. O método de co-precipitação foi eficaz para sintetizar HAs de dimensões nanométricas. Comparado a nHA pura, os difratogramas, espectros de FTIR e parâmetros de rede das nHAs substituídas e co-substituídas exibiram alterações, indicando que a incorporação de cátions resultou em distorções da rede da HA. Os testes de MTT demonstraram que as nHAs sintetizadas não foram citotóxicas, após contato direto com culturas de fibroblastos (L929) e pré-osteoblastos (MC3T3). Os resultados obtidos sugerem que as nHAs co-substituídas por Mg2+/Sr2+ e Zn2+/Sr2+ parecem induzir maior proliferação de células fibroblásticas e osteoblásticas, quando comparado a HA pura e substituída. Os cimentos ósseos desenvolvidos apresentaram capacidade de auto-endurecimento e resistência à lavagem. Além de possuírem alta molhabilidade e um perfil de liberação de íons Ca2+, Sr2+, Mg2+ e Zn2+, que está dentro das doses indicadas para estimular a proliferação de osteoblastos. Os cimentos exibiram excelente biocompatibilidade in vitro em culturas de células fibroblásticas, endoteliais e osteosblásticas. Os cimentos contendo nHAs co-substituídas por Mg2+/Sr2+ exibiram os melhores resultados de viabilidade celular. Após 24 horas de contato indireto com cultura de células fibroblásticas L929, o crescimento celular do grupo C2 foi maior que de todos os grupos em estudo (P < 0,01). Em cultura de células endoteliais EA.hy926, o percentual de células viáveis do grupo C3 foi significativamente maior que de todos os outros grupos, após 24 horas (p < 0,001). A citotoxicidade indireta em cultura de células pré-osteoblásticas MC3T3 revelou que após 48 horas, o grupo C3 apresentou maior viabilidade celular que todos os grupos em estudo (p < 0,01). O teste de formação de tubo sugere que todos os cimentos desenvolvidos possuem potencial angiogênico, sendo que os cimentos contendo nHAs co-substituídas por Zn2+/Sr2+ exibiram resultados significativamente superiores (p < 0,001). Apesar de ser necessário um maior número de testes de biocompatibilidade; a incorporação de íons na rede cristalina das nHAs, que são reconhecidos por afetar a angiogênese e a osteogênese, parece ter resultado no desenvolvimento de cimentos ósseos com potencial para promover a regeneração óssea.


The incorporation of ions into the HA lattice can affect its structure, crystallinity, solubility and cytotoxicity. From the ions present in the composition of bone apatite, Mg2+, Sr2+ and Zn2+ are recognized for promoting angiogenesis and osteogenesis. The substituted HAs can be present better bioactivity for supplying ions with potential to stimulate bone neoformation in grafted sites. This study described the synthesis, characterization and comparison of a range of substituted and co-substituted nHAs contained Sr2+, Mg2+ or Zn2+. Then, it developed bone cement based on HAs with better cytotoxicity results, associated with DCPA, gelatin and chitosan. The nHAs were physicochemically characterized using different techniques. The co-precipitation method was effective for synthesizing HAs with nanometric dimensions. Compared to pure nHA, the diffractograms, FTIR spectra and lattice parameters of the substituted and co-substituted nHAs showed changes, indicating that the incorporation of cations resulted in distortions of the HA lattice. MTT tests demonstrated that the all synthesized nHAs were not cytotoxic after direct contact with fibroblasts (L929) and pre-osteoblasts (MC3T3) cultures. MTT results suggest that Mg2+/Sr2+ and Zn2+/Sr2+ co-substituted nHAs seem to induce more proliferation of fibroblastic and osteoblastic than pure and Mg2+, Sr2+ and Zn2+ substituted nHAs. Bone cements developed showed self-hardening and washout resistance. Also, they Exhibited high wettability and ion release profile with non-toxic concentrations of Ca2+, Sr2+, Mg2+ and Zn2+, range within indicated doses to stimulate the proliferation of osteoblasts. The cement exhibited excellent in vitro cytocompatibility in fibroblastic, endothelial and osteoblastic cell cultures. Cement containing Mg2+/Sr2+ co-substituted nHAs showed better results of the cell viability. After 24 hours of indirect contact with L929 fibroblast culture, the cell growth in the C2 group was highest than all study groups (P <0.01). In EA.hy926 endothelial culture, the cell viability of the C3 group was significantly highest than all other groups after 24 hours (p <0.001). The indirect cytotoxicity in MC3T3 pre-osteoblastic culture revealed that after 48 hours, the C3 group showed the greatest cell viability than all the study groups (p <0.01). The tube formation assay suggests that all cement have angiogenic potential, being that the cements containing Zn2+ / Sr2+ co-substituted nHAs exhibited significantly better results (p < 0,001). Despite being necessary to perform a more significant number of biocompatibility tests, the incorporation of ions into the nHA lattice, which are recognized for affects angiogenesis and osteogenesis, may have resulted in the development of bone cements with the potential to promoting bone regeneration.


Subject(s)
Osteogenesis , Apatites , Bone Cements , Bone Regeneration , Hydroxyapatites , Strontium , Zinc , Magnesium
5.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1873-1879, Nov.-Dec. 2019. graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1055121

ABSTRACT

Hydroxyapatite (HA) is widely used as a biomaterial for bone repair and metallic prostheses coating. The main limitations of the current commercial synthetic hydroxyapatite compounds include high cost and decreased availability, especially for veterinary medicine purposes. Additionally, it is thought that HA biocompatibility and bioactivity could be enhanced by the addition of metal compounds. The objective of this work was to compare the subcutaneous tissue response of commercial and engineered hydroxyapatite obtained from the bovine femur diaphysis mixed with different concentrations of hexa-hydrated Zinc Nitrate in rabbits. Twenty-Five New Zealand female rabbits were used. Five treatments were done according to HA composition (commercial HA, no Zn-HA, 0.1M Zn, 0.2M Zn, and 0.3M Zn). Each treatment was evaluated at five time-points (8, 15, 30, 60 and 90 days post-implantation). Histopathologic analysis was performed to assess inflammation by polymorphonuclear cells infiltration, neovascularization, and fibrosis. Results obtained in this work suggest that general inflammation decreased after 60 days of implantation regardless of Zn concentration. Fibrosis score was increased in the commercial HP compared to control and Zn-hydrated HA. This paper shows that bovine hydroxyapatite is a biocompatible material regardless of nitrate Zinc concentration and has the same properties of commercial hydroxyapatite.(AU)


A hidroxiapatita (HA) é amplamente utilizada como biomaterial para reparo ósseo e revestimento de próteses metálicas. As principais limitações dos atuais compostos comerciais de hidroxiapatita sintética incluem alto custo e menor disponibilidade, especialmente para fins de medicina veterinária. Além disso, acredita-se que a biocompatibilidade e a bioatividade da HA poderiam ser aumentadas pela adição de compostos metálicos. O objetivo deste trabalho foi comparar a resposta tecidual subcutânea de hidroxiapatita comercial e da obtida da diáfise do fêmur bovino misturada com diferentes concentrações de nitrato de zinco hexa-hidratado em coelhos. Foram utilizadas 25 coelhas fêmeas Nova Zelândia. Cinco tratamentos foram feitos de acordo com os compostos de HA (HA comercial, no Zn-HA, 0,1M Zn, 0,2M Zn e 0,3M Zn). Cada tratamento foi avaliado em cinco momentos (oito, 15, 30, 60 e 90 dias após a implantação). A análise histopatológica foi realizada para avaliar a inflamação por infiltração de células polimorfonucleares, neovascularização e fibrose. Os resultados obtidos neste trabalho sugerem que a inflamação geral diminuiu após 60 dias de implantação, independentemente da concentração de Zn. O escore de fibrose foi aumentado na HA comercial comparada com o controle e com a HA hidratada com Zn. Este trabalho mostra que a hidroxiapatita bovina é um material biocompatível independentemente da concentração de nitrato de zinco e possui as mesmas propriedades da hidroxiapatita comercial.(AU)


Subject(s)
Animals , Rabbits , Zinc , Biocompatible Materials , Osseointegration , Hydroxyapatites , Models, Animal
6.
Prensa méd. argent ; 105(11): 836-841, dic2019. graf
Article in English | LILACS, BINACIS | ID: biblio-1049996

ABSTRACT

Composite membrane as a flexible materials have found diverse applications in industrial and biomedical simultaneously, the recent studies have shown intrinsic improvement for membrane properties by inclusion of nanoparticles as a fillers with high portion ratio in inorganic polymers, the combination between two parts polymer and filler is as a result of collection the advantage of two component systems parts together. In this work, samples of polyvinyl alcohol (PVA)-nanoHaydroxyapatite (nHAp) composites were prepared by using casting method. The effects of addition of (nHAp) with different concentration on the optical properties of (PVA- nHAp) composite membrane have been studied by using wavelength range (220-820) nm. The absorption spectra, transmittance spectra, absorption coefficient, energy gap, refractive index, optical conductivity and extinction coefficient have been determined. The results show that the optical constants change with the increase of nHPA concentrations.


Subject(s)
Polyvinyl Alcohol , Spectrum Analysis , Product Synthesis , Nanoparticles , Materials Science , Hydroxyapatites
7.
Rev. cient. odontol ; 7(1): 66-77, ene.-jun. 2019. tab, graf
Article in Spanish | LIPECS, LILACS, LIPECS | ID: biblio-1005864

ABSTRACT

Objetivo: Evaluar la remineralización de lesiones de manchas blancas en el esmalte de premolares humanos a través de la fluorescencia láser utilizando el barniz de flúor al 5% (Duraphat®), la nanohidroxiapatita (Nano P®), y la combinación de ambos agentes, a los 30 días de su aplicación. Método: La muestra estuvo conformada por 40 premolares y dividida en 4 grupos, (1) control (sin agente): saliva artificial, (2) barniz de flúor al 5% (Duraphat®), (3) nanohidroxiapatita (Nano P®), (4) y una combinación de ambos agentes remineralizantes (nanohidroxiapatita - Nano P® y barniz de flúor al 5% - Duraphat®). Se analizaron los datos mediante la prueba de Anova de una vía y test de Bonferroni. Se trabajó con un nivel de significancia p < 0,05. Resultados: La aplicación del barniz de flúor al 5% (Duraphat®) y la nanohidroxiapatita (Nano P®), seguido del barniz de flúor al 5% (Duraphat®) usado individual-mente, mostraron clínicamente valores mayores de remineralización comparado con el grupo control. No se encontró diferencia estadísticamente significativa, al comparar la remineralización de lesiones de manchas blancas medidas a través de fluorescencia láser utilizando dos agentes remineralizantes, el barniz de flúor al 5% (Duraphat®), la nanohidroxiapatita (Nano P®) y una combinación de ambos agentes a los 30 días de su aplicación. Conclusión: La combinación del barniz de flúor al 5% (Duraphat®) y la nano-hidroxiapatita (Nano P®), y barniz de flúor al 5% (Duraphat®) usado individualmente, mostraron clínicamente un incremento en la remineralización de las lesiones de manchas blancas a los 30 días de aplicación. (AU)


Objective: Evaluate the remineralization of white spot lesions on human premolar enamel by laser induced fluorescence following the use of a 5% fluoride varnish (Duraphat®), nanohydroxyapatite (Nano P®), and the combination of both agents 30 days after application. Method: The sample consisted of 40 premolars divided into 4 groups, (1) control (without agent): artificial saliva, (2) 5% fluoride varnish (Duraphat®), (3) nanohydroxyapatite (Nano P ®), (4) and a combination of both remineralizing agents (nanohydroxyapatite - Nano P® and 5% fluoride varnish - Duraphat®). The data were analyzed using the oneway ANOVA and Bonferroni tests. A p value < 0.05 was considered statistically significant. Results: Compared to the control group the highest remineralization values were obtained after the application of the 5% fluoride varnish (Duraphat®) and the nanohydroxyapatite (Nano P®), followed by the 5% fluoride varnish (Duraphat®) used individually. Conclusion: The combination of the 5% fluoride varnish (Duraphat®) and the nanohydroxyapatite (Nano P®), and the 5% fluoride varnish (Duraphat®) used individually improved remineralization of white spot lesions at 30 days. (AU)


Subject(s)
Humans , Tooth Remineralization , Fluorides, Topical , Fluorescence , Hydroxyapatites
8.
Pesqui. bras. odontopediatria clín. integr ; 19(1): 3364, 01 Fevereiro 2019. ilus, tab
Article in English | LILACS, BBO | ID: biblio-998008

ABSTRACT

Objective: To perform a clinical and histological evaluation, characterizing and proving the feasibility of the use of beta tricalcium phosphate (HA/ßTCP) bioceramics as a bone defect repair material, comparing it with autogenous bone and blood clot in terms of osteoinductive, conductive, and genic capacities. Material and Methods: The experiment was based on 3 critical defects in the mandible of 11 New Zealand rabbits. The defects were filled with HA/ßTCP bioceramics and autogenous bone, respectively, collected and ground during the development of defects and blood clots. The animals were euthanized after the 90-day experiment and samples were collected for histomorphological examination. To evaluate differences between the groups, a one-way analysis of variance (ANOVA) was performed with Tukey's post hoc test. An α value lower than 0.05 was considered statistically significant. Results: Microscopy revealed the presence of osteoblasts, osteoclasts, and osteocytes associated or not associated with the presence of mature or immature bone. All the studied materials presented bone neoformation in all cases, with the presence of mature and immature bone. Regarding the presence of HA/ßTCP bioceramic residual material, the same was found in 7 of 11 slides. Conclusion: HA/ßTCP bioceramics were shown to be a biocompatible bone substitute, with osteoinductive and osteoconductive characteristics, accelerating the process of new bone formation when compared with autogenous and blood clotted bone, thereby showing promise for bone defect repair with safety and efficacy.


Subject(s)
Animals , Rabbits , Bone and Bones , Dental Implants , Ceramics/analysis , Hydroxyapatites , New Zealand , Rabbits , Analysis of Variance , Statistics, Nonparametric , Microscopy/instrumentation
9.
Article in English | WPRIM | ID: wpr-762797

ABSTRACT

BACKGROUND: Absorbable plates are widely used in open reduction and internal fixation surgeries for facial bone fractures. Absorbable plates are made of polyglycolic acid (PGA), polylactic acid (PLA), polydioxane (PDS), or various combinations of these polymers. The degradation patterns of absorbable plates made from different polymers and clinical courses of patients treated with such plates have not been fully identified. This study aimed to confirm the clinical courses of facial bone fracture patients using absorbable plates and compare the degradation patterns of the plates. METHODS: A retrospective chart review was conducted for 47 cases in 46 patients who underwent open reduction and internal fixation surgery using absorbable plates to repair facial bone fractures. All surgeries used either PLA/PGA composite-based or poly-L-lactic acid (PLLA)/hydroxyapatite (HA) composite-based absorbable plates and screws. Clinical courses were confirmed and comparisons were conducted based on direct observation. RESULTS: There were no naturally occurring foreign body reactions. Post-traumatic inflammatory responses occurred in eight patients (nine cases), in which six recovered naturally with conservative treatment. The absorbable plates were removed from two patients. PLA/PGA composite-based absorbable plates degraded into fragments with non-uniform, sharp surfaces whereas PLLA/HA composite-based absorbable plates degraded into a soft powder. CONCLUSION: PLA/PGA composite-based and PLLA/HA composite-based absorbable plates showed no naturally occurring foreign body reactions and showed different degradation patterns. The absorbable plate used for facial bone fracture surgery needs to be selected in consideration of its degradation patterns.


Subject(s)
Absorbable Implants , Bone Plates , Facial Bones , Foreign Bodies , Humans , Hydroxyapatites , Polyglycolic Acid , Polymers , Retrospective Studies
10.
Rev. odontol. UNESP (Online) ; 48: e20190040, 2019. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1020753

ABSTRACT

Abstract Introduction Root-scaling procedures on the root surface show to increase root surface roughness during instrumentation. The use of a prophylactic paste reduces the roughness. Objetive This study evaluated the influence of prophylaxis paste on the surface roughness of root dentin after hand instruments (HI), ultrasonic scalers (US) and rotational instruments (RI) were applied to root surfaces. Material and method Fifty bovine roots were prepared and randomly divided into 10 groups (n=5) in which instrumentation with HI, US, or RI was carried out with or without prophylaxis using either conventional or 3% hydroxyapatite paste; additionally, a control group without treatment was included. The Ra and Rz roughness values were measured using a perfilometer. The morphological aspects of the root surfaces were analysed qualitatively by scanning electron microscopy (SEM). Data were analysed using two-way ANOVA followed by Tukey's test (α = 0.05). Result The scaling method and the prophylaxis procedure significantly influenced (p < 0.05) root surface roughness. Treatment with US and prophylaxis with 3% hydroxyapatite paste resulted in lower values ​​of Ra (0.14 µm ± 0.02 µm) and Rz (0.89 µm ± 0.18 µm) compared to the other groups. SEM analysis showed smoother and more homogeneous surfaces in the groups with prophylaxis compared to the groups without prophylaxis. There were no substantial differences between the results of applying different pastes. Conclusion The prophylaxis procedure performed with the experimental paste containing 3% hydroxyapatite reduced the roughness of root surfaces treated with HI, US and RI at the same level as the conventional prophylactic paste.


Resumo Introdução Procedimentos de raspagem na superfície radicular aumentam a rugosidade superficial durante a instrumentação. O uso de pasta profilática pode reduzir a rugosidade. Objetivo Este estudo avaliou a influência da profilaxia com pasta na rugosidade superficial da dentina radicular após instrumentação manual (IH), ultrassom (US) e instrumentos rotatórios (IR) aplicados em superfícies radiculares. Material e método Cinquenta raízes bovinas foram preparadas e divididas aleatoriamente em 10 grupos (n = 5) nos quais a instrumentação com HI, US ou RI foi realizada com ou sem profilaxia usando pasta convencional ou hidroxiapatita a 3%; adicionalmente, um grupo controle sem tratamento foi incluído. As rugosidades de Ra e Rz foram medidas por um perfilômetro. Os aspectos morfológicos das superfícies radiculares foram analisados ​​qualitativamente por microscopia eletrônica de varredura (MEV). Os dados foram analisados ​​por meio de ANOVA de dois fatores, seguido pelo teste de Tukey (α = 0,05). Resultado O método de raspagem e o procedimento de profilaxia influenciaram significativamente (p <0,05) a rugosidade da superfície radicular. O tratamento com US e a profilaxia com pasta de hidroxiapatita ao 3% resultaram em menores valores de Ra (0,14 µm ± 0,02 µm) e Rz (0,89 µm ± 0,18 µm) em relação aos demais grupos. A análise por MEV mostrou superfícies mais lisas e mais homogêneas nos grupos com profilaxia em comparação aos grupos sem profilaxia. Não houve diferenças substanciais entre os resultados da aplicação das diferentes pastas. Conclusão O procedimento de profilaxia realizado com a pasta experimental contendo 3% de hidroxiapatita reduziu a rugosidade das superfícies radiculares tratadas com HI, US e RI no mesmo nível da pasta profilática convencional.


Subject(s)
Periodontics , Dental Prophylaxis , Hydroxyapatites , Microscopy, Electron, Scanning , Dental Scaling , Root Planing , Dental Deposits
11.
Acta cir. bras ; 33(9): 816-823, Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-973498

ABSTRACT

Abstract Purpose: To analyze the therapeutic potentials of different hydroxyapatites used for the correction of bone defects in rats. Methods: Forty rats, male, albino wistar, were distributed in 4 groups. They were submitted to a 3.5 mm defect in tibia. They received low purity hydroxyapatite, Strontium hydroxyapatite and hydroxyapatite doped with gallium, having a seven day evaluation time. Histopathology slides were stained with hematoxylin-eosin, for morphological evaluation. Were analyzed inflammatory processes, necrosis, presence of osteoclasts and osteoblasts, presence of the material, presence of white cells, neovascularization and bone neoformation. Results: It was observed that the groups HAPSr and HAPGa, presented better results of trabecular bone, hyaline cartilage and bone marrow more organized. Conclusion: There was improvement in the repair of the bone defect produced, showing that these hydroxyapatites are effective osteoinductive, osteoconductive, osteintegrant agents and have biocompatibility, and may be indicated for use in defect repairs.


Subject(s)
Animals , Male , Rats , Tibia/surgery , Biocompatible Materials/pharmacology , Bone Remodeling/drug effects , Bone Substitutes/pharmacology , Hydroxyapatites/pharmacology , Materials Testing , Bone Remodeling/physiology , Rats, Wistar
12.
Article in English | WPRIM | ID: wpr-715554

ABSTRACT

Unsintered hydroxyapatite (u-HA) and poly-L-lactide (PLLA) composites (u-HA/PLLA) are osteoconductive and biodegradable. Screw (Super-Fixsorb MX30) and plate (Super-Fixsorb MX40 Mesh) systems made of u-HA/PLLA are typically used in small bones in maxillofacial surgeries. After the resection of bone tumors in larger bones, reconstructions with β-tricalcium phosphate (β-TCP) implants of strong compression resistance have been reported. After a resection, when the cavity is hemispheric- or concave-shaped, stabilization of the implanted β-TCP block is necessary. In the current series, u-HA/PLLA were used to stabilize the mechanically strong implanted low-porous β-TCP blocks in six bone tumor cases, including three giant cell tumors of bone, and one case each of chondroblastoma, chondrosarcoma, and parosteal osteosarcoma. The mean age of patients at the time of surgery was 31.3 years (range, 19 to 48 years). The bones involved were two ilia (posterior), a femur (diaphysis to distal metaphysis), and three tibias (proximal epiphysis, proximal metaphysis to epiphysis, and distal metaphysis to epiphysis). Neither displacement of the implanted β-TCP block nor any u-HA/PLLA-related complications were observed. The radiolucent character of the u-HA/PLLA did not hinder radiological examinations for potential signs of tumor recurrence. The method of using u-HA/PLLA components for the stabilization of β-TCP blocks makes the procedure easy to perform and reliable. It can extend the application of β-TCP blocks in reconstruction surgery.


Subject(s)
Bone Neoplasms , Chondroblastoma , Chondrosarcoma , Durapatite , Epiphyses , Femur , Giant Cell Tumors , Humans , Hydroxyapatites , Methods , Osteosarcoma , Reconstructive Surgical Procedures , Recurrence , Tibia
13.
Article in Korean | WPRIM | ID: wpr-742096

ABSTRACT

PURPOSE: The purpose of this study is to investigate the effect of the titanium implant soaked in saline after RBM surface treatment on the initial osseointegration by comparing the removal torque and the surface analysis compared to the titanium implant with only RBM surface treatment. MATERIALS AND METHODS: The control group was RBM surface treated implants (RBM), and the test group was implants soaked in saline for 2 weeks after RBM surface treatment (RBM+Sal). The control and test group implants were placed in the left and right tibiae of 10 rabbits, respectively, and at the same time, the insertion torque (ITQ) was measured. After 10 days, the removal torque (RTQ) was measured by exposing the implant site. FE-SEM, EDS, Surface roughness and Raman spectroscopy were performed for the surface analysis of the new implant specimens used in the experiments. RESULTS: There was no significant difference in insertion torque and removal torque between RBM surface treated titanium implants and saline-soaked titanium implants after RBM surface treatment. CONCLUSION: Saline soaking after RBM surface treatment of titanium implants did not positively affect the initial osseointegration as compared to titanium implants with only RBM surface treatment.


Subject(s)
Hydroxyapatites , Osseointegration , Rabbits , Sodium Chloride , Spectrum Analysis, Raman , Tibia , Titanium , Torque
14.
Article in Korean | WPRIM | ID: wpr-740067

ABSTRACT

Nonthermal atmospheric plasma has been studied for its many biomedical effects, such as tooth bleaching, wound healing, and coagulation. In this study, the effects of dentinal tubules occlusion were investigated using fluoride-carboxymethyl cellulose (F-CMC) gel, nano-sized hydroxyapatite (n-HA), and nonthermal atmospheric plasma. Human dentin specimens were divided to 5 groups (group C, HA, HAF, HAP, and HAFP). Group HA was treated with n-HA, group HAF was treated with n-HA after a F-CMC gel application, group HAP was treated with n-HA after a plasma treatment and group HAFP was treated with n-HA after a plasma and F-CMC gel treatment. The occlusion of dentinal tubules was investigated using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS), which shows Ca/P ratio. In the EDS results, a higher Ca/P ratio was shown in the groups including n-HA than in the control group. The specimens of group HAP and HAFP had a higher Ca/P ratio in retentivity. In the SEM results, there was not a significant difference in the amount of times applied. Therefore, this study suggests F-CMC gel and n-HA treatment using nonthermal atmospheric plasma will be a new treatment method for decreasing hypersensitivity.


Subject(s)
Carboxymethylcellulose Sodium , Cellulose , Dentin Sensitivity , Dentin , Durapatite , Fluorides , Humans , Hydroxyapatites , Hypersensitivity , Methods , Microscopy, Electron, Scanning , Plasma Gases , Plasma , Spectrometry, X-Ray Emission , Tooth Bleaching , Wound Healing
15.
Article in Korean | WPRIM | ID: wpr-739863

ABSTRACT

PURPOSE: The purpose of this study is to investigate the effect of the titanium implant soaked in saline after RBM and acid etched surface treatment on the initial osseointegration by comparing the removal torque and the surface analysis compared to the titanium implant with only RBM and acid etched surface treatment. MATERIALS AND METHODS: The control group was RBM and acid etched surface treated implants (RBM + HCl), and the test group was implants soaked in saline for 2 weeks after RBM and acid etched surface treatment (RBM + HCl + Sal). The control and test group implants were placed in the left and right tibiae of 10 rabbits, respectively, and at the same time, the insertion torque (ITQ) was measured. After 10 days, the removal torque (RTQ) was measured by exposing the implant site. FE-SEM, EDS, Surface roughness and Raman spectroscopy were performed for the surface analysis of the new implant specimens used in the experiments. RESULTS: There was significant difference in insertion torque and removal torque between control group and experimental group (P = 0.014 < 0.05). Surface roughness of experimental group is higher than control group. CONCLUSION: Saline soaking after RBM and acid etched surface treatment of titanium implants were positively affect the initial osseointegration as compared to titanium implants with only RBM and acid etched surface treatment.


Subject(s)
Hydroxyapatites , Immersion , Osseointegration , Rabbits , Sodium Chloride , Spectrum Analysis, Raman , Tibia , Titanium , Torque
16.
J. appl. oral sci ; 26: e20160531, 2018. graf
Article in English | LILACS, BBO | ID: biblio-893737

ABSTRACT

Abstract Objective: The aim of this study was to evaluate the osteoconductive potential of BoneCeramic™ on bone healing in rat calvaria 5-mm defects. Material and Methods: A 5-mm calvaria bone defect was induced in three groups and the defect was not filled with biomaterial [Clot Group (CG)], autogenous bone (AG), or Bone Ceramic Group (BCG). Animals were euthanized after 14 or 28 days and the bone tissue within the central area of the bone defect was evaluated. Results were compared using ANOVA and Tukey test (p<0.05). Immunohistochemistry was performed using primary antibodies against osteocalcin, RUNX-2, TRAP, VEGF proteins, and 3-dimensional images of the defects in μCT were obtained to calculate bone mineral density (BMD). Results: In BCG, the defect was completely filled with biomaterial and new bone formation, which was statistically superior to that in the GC group, at both time-points (p<0.001 for 14 days; p=0.002 for 28 days). TRAP protein showed weak, RUNX-2 showed a greater immunolabeling when compared with other groups, VEGF showed moderate immunostaining, while osteocalcin was present at all time-points analyzed. The μCT images showed filling defect by BCG (BMD= 1337 HU at 28 days). Conclusion: Therefore, the biomaterial tested was found to be favorable to fill bone defects for the reporting period analyzed.


Subject(s)
Animals , Male , Skull/drug effects , Wound Healing/drug effects , Bone Regeneration/drug effects , Bone Substitutes/pharmacology , Hydroxyapatites/pharmacology , Skull , Skull/pathology , Time Factors , Wound Healing/physiology , Bone Regeneration/physiology , Immunohistochemistry , Bone Density , Osteocalcin/analysis , Treatment Outcome , Rats, Wistar , Bone Substitutes/therapeutic use , Vascular Endothelial Growth Factor A/analysis , Core Binding Factor Alpha 1 Subunit/analysis , Tartrate-Resistant Acid Phosphatase/analysis , Hydroxyapatites/therapeutic use
17.
Araçatuba; s.n; 2018. 79 p. tab, ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1009500

ABSTRACT

Este trabalho teve por objetivo avaliar o tecido ósseo periimplantar formado após o enxerto sinusal com hidroxiapatita e beta-tricálcio fosfato (HA + ß-TCP), nas apresentações em grânulos e em pasta, concomitante à instalação de implantes em coelhos. Trinta e quatro seios maxilares de coelhos foram enxertados com HA + ß-TCP, sendo metade do grupo grânulos e metade do grupo pasta. Concomitantemente, foi realizada a instalação de implantes. Aos 7 e 40 dias pósoperatórios, realizou-se a eutanásia dos animais, e as amostras foram preparadas para as análises tomográfica, microtomográfica, histológica (coloração por hematoxilina e eosina - HE), imunoistoquímica (marcação de fator de transcrição Runt-2 ­ RUNX2 ­, fator de crescimento endotelial vascular ­ VEGF ­, osteocalcina ­ OCN ­ e fosfatase ácida resistente ao tartarato ­ TRAP) e de torque de remoção dos implantes. Na tomografia, foi observada a manutenção da integridade da membrana sinusal, sem extravasamento de material, nos dois grupos e períodos. Parâmetros morfométricos de volume ósseo, porcentagem do volume ósseo e número de trabéculas foram significativamente superiores para o grupo pasta do que para o grupo grânulos aos 7 dias, enquanto que a porosidade foi maior para o grupo grânulos nesse mesmo período. Aos 40 dias, não houve diferença significativa entre os grupos para a maioria dos parâmetros microtomográficos estudados. Nos cortes histológicos corados por HE, observou-se que em ambos os grupos ocorreu a formação de tecido ósseo junto às espiras do implante aos 40 dias, favorecendo a osseointegração. Imunomarcações positivas semelhantes foram encontradas tanto para o fator de diferenciação osteoblástica RUNX2 quanto para o fator de mineralização OCN no osso neoformado nos dois grupos experimentais. A atividade osteoclástica evidenciada pela TRAP mostrou-se semelhante nos dois grupos, com discreto predomínio para o grupo grânulos. Já a marcação positiva para o VEGF mostrou-se aumentada no grupo grânulos, caracterizando um potencial osteocondutor superior nessa apresentação do biomaterial. Ademais, não houve diferenças nos valores de torque de remoção do implante entre ambos os grupos. Logo, as duas apresentações da HA + ß-TCP mostraram resultados favoráveis à osseointegração a longo prazo, com formação de tecido ósseo em quantidade e qualidade semelhantes junto aos implantes(AU)


This work aimed to evaluate the peri-implant bone tissue after maxillary sinus grafting with hydroxyapatite and beta-tricalcium phosphate (HA + ß-TCP), in granular and paste formulations, concomitant with implant placement in rabbits. Thirty four rabbit maxillary sinuses were grafted with HA + ß-TCP, being half of the granular group and half of the paste group. Concomitantly, the implant placement was performed. At 7 and 40 postoperative days, animals were euthanized, and the samples were prepared for tomographic, microtomographic, histological (hematoxylin and eosin staining), immunohistochemical (Runt-related transcription factor 2 ­ RUNX2, vascular endothelial growth factor ­ VEGF ­, osteocalcin ­ OCN ­ and tartrate-resistant acid phosphatase ­ TRAP ­ staining) and implant torque removal analyses. In computed tomography, the maintenance of sinus membrane integrity, with no material extravasation, was observed in both groups and periods. Morphometric parameters of bone volume, percentage of bone volume and trabecular number were significantly higher for paste than granular group at day 7, while the porosity was higher for granular group in this period. At day 40, there were no significant differences between both groups for the majority of the microtomographic parameters studied. In the HE-stained histological sections, it was observed that bone healing around implant threads occurred for both groups at day 40, enhancing osseointegration. Similar positive immunostainings were observed for both the RUNX2 osteoblastic differentiation factor and the OCN mineralization factor in the neoformed bone in the two experimental groups. The osteoclast activity evidenced by TRAP was similar in both groups, with a slight predominance for the granular group. Positive staining for VEGF growth factor was increased in the granular group, characterizing a superior osteoconductive potential for this biomaterial formulation. Besides, there were no differences in the values of implant removal torque between both groups. Thus, the two formulations o H + ß-TCP showed favorable osseointegration results in the long term, with similar amount and quality of bone tissue formation around the implants(AU)


Subject(s)
Bone Regeneration , Calcium Phosphates , Dental Implants , Hydroxyapatites , Maxillary Sinus , Osseointegration
18.
Arq. bras. med. vet. zootec. (Online) ; 69(6): 1539-1550, nov.-dez. 2017. ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-910448

ABSTRACT

Objetivou-se avaliar, histologicamente e por microscopia eletrônica de varredura (MEV), a evolução de defeitos críticos experimentais em rádio de coelhos preenchidos ou não com biocerâmica fosfocálcica nanoestruturada micromacro porosa em grânulos. Utilizaram-se 70 coelhos, Nova Zelândia, adultos jovens, machos, e realizou-se um defeito crítico nos rádios. Os membros constituíram os grupos: GI, biocerâmica lenta, GII, biocerâmica moderada e GIII, controle negativo. Após cada período experimental, os animais foram sacrificados, e os rádios coletados. As avaliações histológicas foram realizadas aos oito, 15, 30, 45, 60, 90 e 120 dias, e as análises de MEV aos 60, 90 e 120 dias. Histologicamente, observou-se processo de reparação óssea mais adiantado nos grupos GI e GII comparando-se ao GIII. Na MEV, constatou-se maior proporção de osso maduro e presença de ósteons secundários nos GI e GII, sendo mais evidente no GII, confirmando os achados histológicos. As cerâmicas promoveram preenchimento completo do defeito, enquanto no grupo controle houve preenchimento no centro do defeito, permanecendo espaços vazios nas laterais. Conclui-se que o emprego das biocerâmicas de absorção lenta e moderada favorece a regeneração óssea completa em defeitos críticos sendo indicadas como substituto ósseo. A maturação óssea ocorre mais precocemente quando se emprega a cerâmica de absorção moderada.(AU)


The objective was to evaluate, through histologic exam and by scanning electron microscopy (SEM), the evolution of experimental critical defects in radio or not filled with nano-structured calcium phosphate micro-macro porous bioceramic granules rabbits. We used 70 rabbits, New Zealand, young adults, males, there was a critical defect in radio. The members were the groups: GI, slow bioceramic, GII, GIII and bioceramic moderate, negative control. After each experimental period, the animals were sacrificed and the radios harvested. Histological evaluations were performed at eight, 15, 30, 45, 60, 90 and 120 days and SEM analyzes at 60, 90 and 120 days. Histologically there was bone healing process earlier in GI and GII compared to GIII. In SEM we observed a higher proportion of mature bone and presence of secondary osteons in GI and GII, being more evident in the GII, confirming the histological findings. Ceramic promoted complete filling of the defect, while the control group was filling in the center of the defect, with empty spaces remaining on the sides. In conclusion, the use of bioceramics, slow and moderate absorption favor complete bone regeneration in critical defects being indicated as a bone substitute. The maturation occurs earlier when employing the ceramic moderate absorption.(AU)


Subject(s)
Animals , Rabbits , Biocompatible Materials/analysis , Calcium Phosphates , Ceramics , Hydroxyapatites/analysis , Microscopy, Electron, Scanning/veterinary , Radius/surgery
19.
Pesqui. vet. bras ; 37(12): 1537-1544, dez. 2017. graf, ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-895392

ABSTRACT

Falhas ósseas são comumente encontradas na medicina veterinária em diferentes enfermidades, principalmente por traumas em grandes animais. Frequentemente faz-se necessário auxiliar este reparo tecidual para melhor correção desta falha. Os biomateriais foram desenvolvidos para cumprir esta função. A fim de avaliar o comportamento celular perante estes substitutos ósseos, a realização de testes in vivo é fundamental. A partir da observação da unidade morfofuncional do tecido é possível avaliar a quantidade e a qualidade do tecido neoformado. Atualmente, em estudos ortopédicos, os ovinos são considerados animais de escolha como modelo experimental. Falhas ósseas foram realizadas experimentalmente em ovinos, onde foram implantados biomateriais à base de quitosana, hidroxiapatita e colágeno. Após 60 dias foi realizada biopsia no local do reparo tecidual e por meio da histomorfometria da matriz orgânica, da análise descritiva da microscopia de luz e da microscopia eletrônica de transmissão, o tecido neoformado foi avaliado e comparado. Na histomorfometria, não houve diferença significativa quanto à quantidade de tecido neorformado do grupo controle e do grupo com biomaterial, porém quando comparado ao osso pré-existente, retirado no momento da confecção da falha, a área de matriz óssea foi menor. Na descrição da microscopia de luz e em maiores detalhes na análise ultra estrutural, observou-se o biomaterial em contato íntimo com o tecido neoformado, sugerindo boa biocompatibilidade. Foi possível observar o padrão da reparação tecidual, onde o membro controle e o membro com biomaterial não diferiram quanto à arquitetura tecidual, porém nas amostras com o implante do biomaterial foi identificada a presença do mesmo. Todas estas informações sugerem que o biomaterial não prejudicou a regeneração óssea, apresentou boa biocompatibilidade e denota potencial para auxiliar na rotina ortopédica de grandes animais.(AU)


Bone defects are commonly found in veterinary medicine through different disease such as trauma, especially in large animals. Frequently it is necessary to assist this tissue repair for better regeneration. Biomaterials in general are designed to this function. In order to understand the bone cells in the presence of bone substitutes, tests in vivo are essential for these studies. The quantity and quality of new tissue formation can be assessed by observation of tissue morphofunctional unit. Currently, in orthopedic studies sheep are considerated animals of choice for experimental development. Bone defects were performed experimentally in sheep and were implanted chitosan, hydroxyapatite and collagen biomaterials. After 60 days, biopsy was performed at the site of tissue repair and the new tissue formation was described, evaluated and compared by organic matrix bone histomorphometry and electronic transmission microscopy. After hystomorfometry analysis there was no difference between control group and biomaterial group, but when compare with pre-existent tissue, the values are smaller. In descriptive analysis was observed intimate contact with biomaterial and new tissue formation suggesting biocompatibility. It observed the pattern of tissue repair in control group and biomaterial group did not differ in the architecture tissue. However, in the biomaterial group was identified presence of the biomaterial in the specimen. All these data suggest that the biomaterial did not impair bone regeneration, had good biocompatibility and potential to assistant in orthopedic routine of large animals.(AU)


Subject(s)
Animals , Tibia/transplantation , Biocompatible Materials/analysis , Bone Regeneration , Sheep/surgery , Collagen/therapeutic use , Chitosan/therapeutic use , Hydroxyapatites/therapeutic use
20.
Univ. sci ; 22(3): 215-236, Oct.-Dec. 2017. ilus, graf, tab
Article in English | LILACS, COLNAL | ID: biblio-904715

ABSTRACT

Abstract Hydroxyapatite (HAp) was obtained from tilapia scales by two extraction methods: direct calcination and acid-base treatment. The physicochemical characteristics of the obtained HAps were evaluated by thermogravimetric analysis, X-ray fluorescence, X-ray diffraction, scanning electron microscopy, surface area, infrared spectroscopy, and basicity measurement at 298 K by CO2 -pulse titration. Furthermore, the CO2 capture capacity of the solids at high temperature was also determined. Both methods showed the presence of a HAp phase although significant differences in the properties of the solids were found. The HAp obtained by direct calcination, exhibited a lower crystallinity and a greater surface area and basicity than the HAp obtained by the acid-base treatment. These features were correlated with the solid's CO2 capture capacity. In this work, CO2 capture capacity values for HAp yielded by calcination ranged from 2.5 to 3.2 mg CO2 /g captured at 973 K, and for the acid-base treatment-derived HAp, CO2 capture capacity values between 1.2 to 2.5 mg CO2 /g were recorded. These results reveal the potential of HAps extracted from tilapia scales as solids with high CO2 capture capacity, thermal stability, and capture/release cycles reversibility.


Resumen Se obtuvo hidroxiapatita (HAp) de escamas de tilapia por dos métodos de extracción: calcinación directa y tratamiento ácido-base. Las características fisicoquímicas de las HAps obtenidas fueron evaluadas por análisis termogravimétrico, fluorescencia de rayos X, difracción de rayos X, microscopía electrónica de barrido, área superficial, espectroscopia infrarroja y medición de basicidad a 298 K por titulación por pulso de CO2. Adicionalmente, se determinó la capacidad de captura de CO2 de los sólidos a alta temperatura. Ambos métodos mostraron la presencia de una fase de HAp, aunque se encontraron diferencias significativas en las propiedades de los sólidos. La HAp obtenida por calcinación directa exhibió una menor cristalinidad y una mayor área superficial y basicidad que la HAp obtenida con el tratamiento acido-base. Estas características se correlacionaron con la capacidad de captura de CO2 del sólido. En este trabajo, los valores de captura del CO2 con la HAp producidos por calcinación oscilaron entre 2.5 to 3.2 mg CO2/g capturado a 973 K, y con la HAp derivada del tratamiento ácido-base, se registraron valores de captura entre 1.2 to 2.5 mg CO2/g. Estos resultados revelan el potencial de HAps extraídos de escamas de tilapia como sólidos con una alta capacidad de captura de CO2, estabilidad térmica y reversibilidad de los ciclos de captura/liberación.


Resumo A hidroxiapatita (HAp) foi obtida a partir da escama de tilapia usando dois métodos de extração: calcinação direta e tratamento ácido-base. As características físico-químicas das hidroxiapatitas foram avaliadas por análise termogravimétrica, fluorescência de raios-X, difração de raios-X, microscopia eletrônica de varredura, área superficial, espectroscopia de infravermelho e medição de basicidade a 298 K por titulação de pulso de CO2. Além disso, determinou-se a capacidade de captura de CO2 dos sólidos a alta temperatura. Os dois métodos mostraram a presença da fase HAp, no entanto, diferenças significativas foram encontradas nas propriedades dos sólidos, sendo a HAp obtida por calcinação direta a que apresentou menor cristalinidade, maior área superficial e basicidade, características que foram correlacionadas com a capacidade de captura de CO2. Foram encontrados valores entre 2.5 a 3.2 mg CO2/g capturado a 973 K para a HAp obtida por calcinação e, entre 1.2 a 2.5 mg CO2/g para a HAp obtida por tratamento ácido-base. Isto revelou o potencial de HAp's extraídas da escama de tilapia como sólidos com alta capacidade de captura de CO2, estabilidade térmica e reversibilidade na liberação de CO2.


Subject(s)
Carbon Dioxide , Tilapia , Hydroxyapatites/analysis
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