RESUMO
The bone-induction capacity of a porous biphasic calcium phosphate (pBCP) using heterotopic implantation in mouse (mHI-model) and its efficacy as substitute for autograft in mandibular critical-size defect in rabbit (rabMCSD-model) was investigated. In mHI-model, pBCP was implanted into the thigh muscles and bone formation was histomorphometrically and immunohistochemically evaluated. In rabMCSD-model, 13 mm bone defects were treated with pBCP or autograft and bone repair comparatively evaluated by radiographic and histomorphometric methods. In mHI-model, formed bone and immunolabeling for bone morphogenetic protein-2 and osteopontin were observed in 90% of pBCP implanted samples after 12 weeks. In rabMCSD-model neither statistically significant difference was found in newly formed bone between pBCP and autograft groups at 4 weeks (18.8 ± 5.5% vs 27.1 ± 5.6%), 8 weeks (22.3 ± 2.7% vs 26.2 ± 5.1), and 12 weeks (19.6 ± 4.7% vs 19.6 ± 2.3%). At 12 weeks, the stability and contour of the mandible were restored in both treatments. Near tooth remaining, pBCP particles were covered by small amount of mineralized tissue exhibiting perpendicular attachments of collagen fiber bundles with histological characteristic of acellular cementum. Within the limitations of this study, it was concluded that pBCP is osteoinductive and able to stimulate the new formation of bone and cementum-like tissues in rabMCSD-model, suggesting that it may be an alternative to treatment of large bone defect and in periodontal regenerative therapy. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1546-1557, 2018.
Assuntos
Substitutos Ósseos , Cerâmica , Hidroxiapatitas , Mandíbula , Traumatismos Mandibulares , Osteogênese/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacocinética , Proteína Morfogenética Óssea 2/farmacologia , Substitutos Ósseos/química , Substitutos Ósseos/farmacocinética , Substitutos Ósseos/farmacologia , Transplante Ósseo , Cerâmica/química , Cerâmica/farmacocinética , Cerâmica/farmacologia , Modelos Animais de Doenças , Hidroxiapatitas/química , Hidroxiapatitas/farmacocinética , Hidroxiapatitas/farmacologia , Masculino , Mandíbula/metabolismo , Mandíbula/patologia , Traumatismos Mandibulares/metabolismo , Traumatismos Mandibulares/patologia , Traumatismos Mandibulares/terapia , Camundongos , Camundongos Endogâmicos BALB C , CoelhosRESUMO
This work aimed to develop novel composite biomaterials for bone tissue engineering (BTE) made of bioactive glass nanoparticles (Nbg) and alginate cross-linked with Cu(2+) or Ca(2+) (AlgNbgCu, AlgNbgCa, respectively). Two-dimensional scaffolds were prepared and the nanocomposite biomaterials were characterized in terms of morphology, mechanical strength, bioactivity, biodegradability, swelling capacity, release profile of the cross-linking cations and angiogenic properties. It was found that both Cu(2+) and Ca(2+) are released in a controlled and sustained manner with no burst release observed. Finally, in vitro results indicated that the bioactive ions released from both nanocomposite biomaterials were able to stimulate the differentiation of rat bone marrow-derived mesenchymal stem cells towards the osteogenic lineage. In addition, the typical endothelial cell property of forming tubes in Matrigel was observed for human umbilical vein endothelial cells when in contact with the novel biomaterials, particularly AlgNbgCu, which indicates their angiogenic properties. Hence, novel nanocomposite biomaterials made of Nbg and alginate cross-linked with Cu(2+) or Ca(2+) were developed with potential applications for preparation of multifunctional scaffolds for BTE.
Assuntos
Cálcio , Cobre , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nanocompostos/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacocinética , Cálcio/química , Cálcio/farmacocinética , Cobre/química , Cobre/farmacocinética , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: The aim of this study was to produce dense granules of tricalcium phosphate (ß-TCP) and magnesium (Mg) substituted ß-TCP, also known as ß-TCMP (Mg/Ca=0.15 mol), in order to evaluate the impact of Mg incorporation on the physicochemical parameters and in vitro biocompatibility of this novel material. MATERIAL AND METHODS: The materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), electron microscopy and inductively coupled plasma (ICP). Biocompatibility was assayed according to ISO 10993-12:2007 and 7405:2008, by two different tests of cell survival and integrity (XTT and CVDE). RESULTS: The XRD profile presented the main peaks of ß-TCP (JCPDS 090169) and ß-TCMP (JCPDS 130404). The characteristic absorption bands of TCP were also identified by FTIR. The ICP results of ß-TCMP granules extract showed a precipitation of calcium and release of Mg into the culture medium. Regarding the cytotoxicity assays, ß-TCMP dense granules did not significantly affect the mitochondrial activity and relative cell density in relation to ß-TCP dense granules, despite the release of Mg from granules into the cell culture medium. CONCLUSION: ß-TCMP granules were successfully produced and were able to release Mg into media without cytotoxicity, indicating the suitability of this promising material for further biological studies on its adequacy for bone therapy.
Assuntos
Materiais Biocompatíveis/toxicidade , Fosfatos de Cálcio/toxicidade , Magnésio/toxicidade , Análise de Variância , Materiais Biocompatíveis/farmacocinética , Substitutos Ósseos/farmacocinética , Substitutos Ósseos/toxicidade , Fosfatos de Cálcio/farmacocinética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Magnésio/farmacocinética , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/efeitos dos fármacos , Análise Espectral , Fatores de Tempo , Testes de Toxicidade , Difração de Raios XRESUMO
Objective: The aim of this study was to produce dense granules of tricalcium phosphate (β-TCP) and magnesium (Mg) substituted β-TCP, also known as β-TCMP (Mg/Ca=0.15 mol), in order to evaluate the impact of Mg incorporation on the physicochemical parameters and in vitro biocompatibility of this novel material. Material and Methods: The materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), electron microscopy and inductively coupled plasma (ICP). Biocompatibility was assayed according to ISO 10993-12:2007 and 7405:2008, by two different tests of cell survival and integrity (XTT and CVDE). Results: The XRD profile presented the main peaks of β-TCP (JCPDS 090169) and β-TCMP (JCPDS 130404). The characteristic absorption bands of TCP were also identified by FTIR. The ICP results of β-TCMP granules extract showed a precipitation of calcium and release of Mg into the culture medium. Regarding the cytotoxicity assays, β-TCMP dense granules did not significantly affect the mitochondrial activity and relative cell density in relation to β-TCP dense granules, despite the release of Mg from granules into the cell culture medium. Conclusion: β-TCMP granules were successfully produced and were able to release Mg into media without cytotoxicity, indicating the suitability of this promising material for further biological studies on its adequacy for bone therapy.
Assuntos
Materiais Biocompatíveis/toxicidade , Fosfatos de Cálcio/toxicidade , Magnésio/toxicidade , Análise de Variância , Materiais Biocompatíveis/farmacocinética , Substitutos Ósseos/farmacocinética , Substitutos Ósseos/toxicidade , Fosfatos de Cálcio/farmacocinética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Teste de Materiais , Microscopia Eletrônica de Varredura , Magnésio/farmacocinética , Osteoblastos/efeitos dos fármacos , Análise Espectral , Fatores de Tempo , Testes de Toxicidade , Difração de Raios XRESUMO
Compósitos hidroxiapatita: colágeno foram preparados em diferentes proporções a fim de se determinar qual a melhor proporção para a incorporação de antibiótico. A melhor proporção de HA:colágeno obtida foi de 10:1 (m/m), a qual foi caracterizada por Calorimetria Exploratória Diferencial (DSC), espectroscopia no Infravermelho (IV), Microscopia Eletrônica de Varredura (MEV) e teste de hidrofilicidade, sendo então posteriormente utilizada na incorporação e liberação de ciprofloxacina. As curvas calorimétricas mostraram transições em torno de 40 graus C, referentes à desnaturação do colágeno. A razão A1235/A1450 do espectro no infravermelho do compósito HA:col (10:1) foi de 1,12 e mostra que o colágeno está preservado neste compósito. As fotomicrografias mostram fibras de colágeno uniformemente distribuídas em torno da hidroxiapatita. O teste de hidrofilicidade do compósito mostrou que o material foi capaz de absorver 183,2 por cento de água em relação à sua massa seca. Para os estudos preliminares de liberação de antibiótico incorporou-se cerca de 5 por cento de cloridrato de ciprofloxacina em massa no compósito HA:col (10:1), no momento de preparo do mesmo. O experimento de liberação in vitro foi realizado em tampão fostato salino (PBS), pH 7,4 a 37 graus C, durante 72 horas, mostrando uma liberação máxima em torno 90 por cento, após 10 horas de imersão. A liberação da droga nas primeiras quatro horas obedece ao modelo de Higuchi, sendo indicativo de processo de difusão pelos poros da matriz