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Agradecimentos: The authors acknowledge the facility support from the Universidade Federal do ABC, Central Experimental Multiusuário, Politecnico di Torino, Universidade de São Paulo, Hospital Israelita Albert Einstein and Jena University. The authors also thank MSc. Marcela Tercini and BSc. João Francisco Almeida by the technical support in the FE-SEM analysis. We also acknowledge E.S.R. Somessari from Centro de Tecnologia das Radiações at Instituto de Pesquisas Energéticas e Nucleares (SETRS/CTR-IPEN) for technical support on sample sterilization. Furthermore, the authors appreciate the financial support from FAPESP (#2016/16512-9, #2011/19924-2 and 2020/00329-6), FINEP, CNPq (#130637/2016-5), and CAPES (code 002) Abstract: Magnetic bioactive glass-ceramics are biomaterials applied for magnetic hyperthermia in bone cancer treatment, thereby treating the bone tumor besides regenerating the damaged bone. However, combining high bioactivity and high saturation magnetization remains a challenge since the thermal treatment step employed to grow magnetic phases is also related to loss of bioactivity. Here, we propose a new nanocomposite made of superparamagnetic iron oxide nanoparticles (SPIONs) dispersed in a sol-gel-derived bioactive glass matrix, which does not need any thermal treatment for crystallization of magnetic phases. The scanning and transmission electron microscopies, X-ray diffraction, and dynamic light scattering results confirm that the SPIONs are actually embedded in a nanosized glass matrix, thus forming a nanocomposite. Magnetic and calorimetric characterizations evidence their proper behavior for hyperthermia applications, besides evidencing inter-magnetic nanoparticle interactions within the nanocomposite. Bioactivity and in vitro characterizations show that such nanocomposites exhibit apatite-forming properties similar to the highly bioactive parent glass, besides being osteoinductive. This methodology is a new alternative to produce magnetic bioactive materials to which the magnetic properties only rely on the quality of the SPIONs used in the synthesis. Thereby, these nanocomposites can be recognized as a new class of bioactive materials for applications in bone cancer treatment by hyperthermia FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP FINANCIADORA DE ESTUDOS E PROJETOS - FINEP CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES Fechado

Orientador: Americo Bortolazzo Correr Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: O objetivo deste estudo foi avaliar o ângulo de contato, a habilidade de penetração e potencial de remineralização de infiltrantes resinosos contendo partículas bioativas. Foram utilizados dois infiltrantes experimentais: TEGDMA (100% de trietileno glicol dimetacrilato) e T/B (75% de TEGDMA e 25% de bisfenol glicidil dimetacrilato etoxilado - BisEMA), além do infiltrante Icon©. A estas bases adicionou-se partículas de biovidro de fosfossilicato de cálcio e sódio (Bag45s5), ou nanopartículas de hidroxiapatita (nHap), nas concentrações de 0, 10 e 15%vol. O ângulo de contato foi avaliado em esmalte bovino pelo método da gota séssil em viscosímetro com câmera acoplada, sendo calculada a média de três medidas para cada espécime (n=6). Para avaliação da habilidade de penetração, lesões subsuperficiais semelhantes à cárie foram produzidas em esmalte na face oclusal de molares humanos hígidos e infiltradas com os infiltrantes resinosos. A penetração dos materiais foi verficada em fatias obtidas dessas coroas, por meio de microscopia confocal de varredura a laser (n=3). Para a avaliação do potencial de remineralização, lesões subsuperficiais semelhantes à cárie foram produzidas em esmalte na face vestibular de coroas de molares humanos e infiltradas pelos infiltrantes resinosos. Essas coroas foram submetidas à ciclagem de pH (solução Des/Re) por um mês. A microdureza Knoop (KHN) foi avaliada a 20, 40, 60, 80 e 100 ?m da superfície externa do esmalte, em 3 linhas (5, 100 e 200 ?m distante da lesão) (n=5). Para auxílio na avaliação de remineralização das partículas, a morfologia e o tamanho das mesmas foram analisadas por microscopia eletrônica de transmissão e varredura (MET e MEV), enquanto sua estrutura cristalina foi analisada por difração de raios X (DRX). Os dados referentes a ângulo de contato e habilidade de penetração foram avaliados quanto à normalidade e submetidos à ANOVA dois-fatores e teste de Tukey (?=0,05). Os dados referentes ao potencial de remineralização foram submetidos aos testes de Friedman e Kruskal-Wallis (?=0,05). Os resultados mostraram que a adição de 10 e 15% de nHap reduziu o ângulo de contato do Icon® e a adição de 15% de nHap reduziu o ângulo de contato do T/B. TEGDMA apresentou ângulo de contato menor que Icon® nos grupos sem adição de partículas e valores menores que Icon® e T/B nos grupos com adição de 15% de Bag45s5. T/B apresentou menores valores que Icon® para grupos com adição de 15% nHap. A adição de partículas não interferiu na habilidade de penetração dos infiltrantes. Todos os grupos com matriz resinosa T/B apresentaram habilidade de penetração inferior aos infiltrantes TEGDMA e Icon®. Icon© e T/B + Bag45s5 15%vol apresentaram diferentes valores de KHN para os pontos avaliados intra-grupo, em ambos foi verificado maior dureza nos pontos mais profundos do esmalte. Icon© + Bag45s5 10%vol mostrou, em vários pontos, valores de KHN mais baixos que Icon©, T/B + nHap 10%vol, T/B + Bag45s5 10%vol e T/B + nHap 15%vol. Assim, concluiu-se que adição de nHap reduz o ângulo de contato de Icon® e T/B. A adição das partículas nHap e Bag45s5 não interfere na habilidade de penetração do Icon®, TEGDMA e T/B. E o TEGDMA e o Icon® apresentam melhor penetrabilidade que T/B. A aplicação do infiltrante T/B com adição de Bag45s5 15%vol confere um melhor padrão de remineralização às áreas mais profundas do esmalte, em relação às áreas superficiais. A adição das partículas nHap e Bag45s5 nas concentrações 10%vol e 15%vol não aumenta o potencial de remineralização dos infiltrantes Icon©, TEGDMA e T/B Abstract: The aim of this study was to evaluate the contact angle, the penetration ability and the remineralization potential of resin infiltrants containing bioactive particles addition. Two experimental infiltrants made with TEGDMA (100% triethylene glycol dimethacrylate) or T/B (75% TEGDMA and 25% ethoxylated bisphenol A glycol dimethacrylate - BisEMA), and the commercially available infiltrant Icon© were used. To these materials it was added 0, 10 or 15v% of a sodium calcium phosphosilicate bioglass particles (Bag45s5), or hydroxyapatite nanoparticles (nHap). The contact angle was evaluated on bovine enamel by the sessile drop method in a coupled-camera viscometer. The mean of three measurements for each specimen was calculated (n=6). For penetration ability evaluation, caries-like subsurface lesions were produced in the enamel of occlusal face of human sound molar crowns and infiltrated with resin infiltrants. The materials penetration was verified in slices obtained from these crowns, by means of confocal laser scanning microscopy (n=3). For remineralization potential evaluation, artificial caries was produced in the enamel of vestibular face of human crowns, where infiltrants were applied. These crowns went through pH cycling process (DS-RS) for a month. Knoop microhardness (KHN) was measured at 20, 40, 60, 80 and 100?m from the outer enamel surface, in 3 rows (5, 100 and 200?m to lesion) (n=5). To aid in the evaluation of particle remineralization, particles morphology and dimension were analyzed by transmission and scanning electron microscopies (TEM and SEM), while its crystal structure was analyzed by X-ray diffraction (XRD). Contact angle and penetration ability data were checked for normality and submitted to two-way ANOVA and Tukey's test (? = 0.05). Remineralization potential data was submitted to Friedman and Kruskal-Wallis tests (?=0.05). The results showed that addition of 10 and 15v% nHap significantly decreased contact angle values for Icon®, and addition of 15v% nHap significantly decreased contact angle values for T/B. TEGDMA presented lower contact angle values than Icon® in the groups without particles and lower values than Icon® and T/B in 15v% Bag45s5 groups. T/B presented lower contact angle values than Icon® for groups with addition of 15v% nHap. The addition of particles did not interfere with the penetration ability of infiltrants. All groups with T/B resin matrix presented lower penetration ability than those with TEGDMA and Icon®. Icon© and T / B + Bag45s5 15v% showed differences in KHN values according to the intragroup evaluated sites, in both was verified higher hardness pattern at deeper sites. Icon© + Bag45s5 10v% showed, in several sites, lower KHN values than Icon©, T/B + nHap 10v%, T/B + Bag45s5 10v% and T/B + nHap 15v%. Thus, it was concluded that nHap addition reduces the contact angle of Icon® and T/B. The addition of nHap and Bag45s5 particles does not interfere with the penetration ability of Icon®, TEGDMA and T/B. TEGDMA and Icon® have better penetrability than T/B. T/B + Bag45s5 15v% presents higher KHN in deeper enamel areas. The addition of nHap and Bag45s5 at 10 and 15v% in Icon©, TEGDMA and T/B did not increase their remineralization potential Doutorado Materiais Dentários Doutor em Materiais Dentários CAPES 0878/2018 CNPQ 141962/2016-0

Orientador: Altair Antoninha Del Bel Cury Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: O comportamento bioativo em materiais odontológicos tem sido investigado em diversos campos da odontologia. Alguns estudos modificaram com sucesso cerâmicas odontológicas adicionando vidro bioativo (VB), tornando esses materiais capazes de exibir um comportamento bioativo. No entanto, essas composições têm apresentado propriedades mecânicas inferiores que podem estar relacionadas a um tratamento térmico inadequado. Além disso, outras propriedades como solubilidade química, dureza, rugosidade de superfície e estabilidade de cor, que podem ser afetadas, não foram ainda avaliadas. Assim, o objetivo deste estudo foi avaliar propriedades físicas e mecânicas de uma cerâmica feldspática reforçada por leucita modificada por vidro bioativo. Para isso, três composições de cerâmica odontológica (CO) modificada por vidro bioativo 58S foram sintetizados pelo método de sol-gel (VB20: 80% em peso de CO + 20% em peso de VB, VB30: 70% em peso de CO + 30% em peso de VB e VB40: 60% em peso de CO + 40% em peso de VB). Inicialmente, as composições foram caracterizadas por calorimetria exploratória diferencial e sua resistência à flexão biaxial foram testadas após sinterização a diferentes temperaturas (910, 950, 1000 e 1050 °C). Um grupo composto por 100% de CO, sinterizado de acordo com as recomendações do fabricante (910 °C), foi utilizado como grupo de controle. A temperatura de sinterização que promoveu os maiores valores de resistência à flexão para cada composição (VB20 a 950 °C, VB30 a 1000 °C e VB40 a 1050 °C) foram utilizadas para a avaliação do comportamento bioativo, solubilidade química, microdureza, rugosidade de superfície e estabilidade de cor. Para verificação do comportamento bioativo os grupos foram avaliados por difração de raios-X (DRX) e espectroscopia de infravermelho por transformada de Fourier (FTIR) com e sem imersão em fluido corporal simulado (Simulated Body Fluid, SBF) por 21 dias. Para a microdureza (n=5), foram avaliados em um microdurômetro com identador Knoop. A solubilidade (n=10) foi avaliada por imersão em solução de ácido acético a 4% por 16 horas, a rugosidade de superfície (n=10) por um perfilômetro óptico 3D e a estabilidade de cor (n=10) pelo sistema CIEL*a*b*. As composições experimentais mostraram indícios de comportamento bioativo após a imersão em SBF. Todos os grupos experimentais apresentaram resistência à flexão menor do que o grupo controle (p

Agradecimentos: This study was financed by the State of São Paulo Research Foundation (FAPESP) (grant number 2018/04630-2), by FAEPEX UNICAMP through a research grant (3164/18), and by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. The authors also thank the Oral Biochemistry Laboratory at Piracicaba Dental School at the University of Campinas (UNICAMP) for use of the microbiology facility, and the Brazilian Nanotechnology National Laboratory (LNNano) at the Brazilian Center of Research in Energy and Materials (CNPEM) for use of the CLSM facilities Abstract: Hypothesis: Although bioactive glass (BG) particle coatings were previously developed by different methods, poor particle adhesion to surfaces and reduced biological effects because of glass crystallization have limited their biomedical applications. To overcome this problem, we have untangled, for the first time, plasma electrolytic oxidation (PEO) as a new pathway for the synthesis of bioactive glass-based coating (PEO-BG) on titanium (Ti) materials. Experiments: Electrolyte solution with bioactive elements (Na2SiO3-5H(2)O, C4H6O4Ca, NaNO3, and C3H7Na2O6P) was used as a precursor source to obtain a 45S5 bioglass-like composition on a Ti surface by PEO. Subsequently, the PEO-BG coating was investigated with respect to its surface, mechanical, tribological, electrochemical, microbiological, and biological properties, compared with those of machined and sandblasted/acid-etched control surfaces. Findings: PEO treatment produced a coating with complex surface topography, Ti crystalline phases, superhydrophilic status, chemical composition, and oxide layer similar to that of 4555-6G (similar to 45.0Si, 24.5 Ca, 24.5Na, 6.0P w/v%). PEO-BG enhanced Ti mechanical and tribological properties with higher corrosion resistance. Furthermore, PEO-BG had a positive influence in polymicrobial biofilms, by reducing pathogenic bacterial associated with biofilm-related infections. PEO-BG also showed higher adsorption of blood plasma proteins without cytotoxic effects on human cells, and thus may be considered a promising biocompatible approach for biomedical implants FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES Fechado

Agradecimentos: The authors acknowledge the use of the analytical instrumentation facility at Institute of Chemistry, University of Campinas, which is supported by the State of Paulo. This work was carried out with the support of the São Paulo Research Foundation - FAPESP (Grant: 2016/24372-2, 2010/05394-9) and the National Council for Scientific and Technological Development (CNPq/PIBITI) and the Coordination for the Improvement of Higher Level -or Education-Personnel (CAPES) for the financial support. We also would like to acknowledge Prof. Dr. Antonio Carlos Boschero for providing us with the SkyScan 1278 (FAPESP EMU 2009/54121-8) for the µCT analysis Abstract: Here, we investigated the biocompatibility of a bioactive sodium calcium silicate glass containing 2.6 mol% Nb2O5 (denoted BGPN2.6) and compare the results with the archetypal 45S5 bioglass. The glass bioactivity was tested using a range of in vitro and in vivo experiments to assess its suitability for bone regeneration applications. in vitro studies consisted of assessing the cytocompatibility of the BGPN2.6 glass with bone-marrow-derived mesenchymal stem cells (BM-MSCs). Systemic biocompatibility was verified by means of the quantification of biochemical markers and histopathology of liver, kidneys, and muscles. The glass genotoxicity was assessed using the micronucleus test. The regeneration of a calvarial defect was assessed using both qualitative and quantitative analysis of three-dimensional microcomputed tomography images. The BGPN2.6 glass was not cytotoxic to BM-MSCs. It is systemically biocompatible causing no signs of damage to high metabolic and excretory organs such as the liver and kidneys. No mutagenic potential was observed in the micronucleus test. MicroCT images showed that BGPN2.6 was able to nearly fully regenerate a critical-sized calvarial defect and was far superior to standard 45S5 Bioglass. Defects filled with BGPN2.6 glass showed over 90% coverage compare to just 66% for 45S5 Bioglass. For one animal the defect was completely filled in 8?weeks. These results clearly show that Nb-containing bioactive glasses are a safe and effective biomaterial for bone replacement Resumo: CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Agradecimentos: The authors acknowledge the use of the analytical instrumentation facility at the Institute of Chemistry, the University of Campinas, which is supported by the State of Paulo. This work was carried out with the support of the São Paulo Research Foundation - FAPESP (Grant: 2010/05394-9, 2010/12376-5, 2010/00863-0, 2011/09240-9, and 2011/17877-7) and the National Council for Scientific and Technological Development (CNPq/PIBITI) for the financial support. The authors would like to thank Brazilian Nanotechnology National Laboratory (LNNano) for technical support during SEM and AFM analyzes especially Dr. Carlos Alberto Rodrigues Costa for his technical assistance with AFM analysis Abstract: In vitro and in vivo experiments were undertaken to evaluate the solubility, apatite-forming ability, cytocompatibility, osteostimulation, and osteoinduction for a series of Nb-containing bioactive glass (BGNb) derived from composition of 45S5 Bioglass. Inductively coupled plasma optical emission spectrometry (ICP-OES) revealed that the rate at which Na, Ca, Si, P, and Nb species are leached from the glass decrease with the increasing concentration of the niobium oxide. The formation of apatite as a function of time in simulated body fluid was monitored by 31P Magic Angle Spinning (MAS) Nuclear magnetic resonance spectroscopy. Results showed that the bioactive glasses: Bioglass 45S5 (BG45S5) and 1 mol%-Nb-containing-bioactive glass (BGSN1) were able to grow apatite layer on their surfaces within 3 h, while glasses with higher concentrations of Nb2O5 (2.5 and 5 mol%) took at least 12 h. Nb-substituted glasses were shown to be compatible with bone marrow-derived mesenchymal stem cells (BMMSCs). Moreover, the bioactive glass with 1 mol% Nb2O5 significantly enhanced cell proliferation after 4 days of treatment. Concentrations of 1 and 2.5 mol% Nb2O5 stimulated osteogenic differentiation of BMMSCs after 21 days of treatment. For the in vivo experiments, trial glass rods were implanted into circular defects in rat tibia in order to evaluate their osteoconductivity and osteostimulation. Two morphometric parameters were analyzed: (a) thickness of new-formed bone layer and (b) area of new-formed subperiostal bone. Results showed that BGNb bioactive glass is osteoconductive and osteostimulative. Therefore, these results indicate that Nb-substituted glass is suitable for biomedical applications CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

Resumo: Varias biocerâmicas sao capazes de se ligarem a tecidos vivos (bioatividade), no entanto apresen- tam propriedades mecânicas muito diferentes daquelas exibidas por tecidos naturais. Tal fato acaba por restringir o uso desses materiais em um mais extenso numero de aplicacoes biomedicas. Compositos de matriz polimerica reforcada com uma fase bioativa podem combinar o comportamento bioativo caracteris- tico de algumas biocerâmicas com propriedades mecânicas proximas a de tecidos humanos. O presente trabalho tem como objetivo sintetizar e caracterizar compositos de matriz polimerica reforcada por parti- culas de vidro bioativo. Os compositos foram produzidos a partir da polimerizacao em massa de metacrilato de metila na presenca de particulas de vidro bioativo (vidro de silicato de calcio, fosforo e sodio). Particu- las de vidro foram adicionadas ao monomero em diversas concentracoes para permitir a variacao das propriedades mecânicas e da bioatividade desses compositos. A bioatividade dos materiais produzidos foi avaliada atraves de testes in vitro realizados a 37oC em uma solucao simuladora do fluido humano por periodos de tempo de 0 hora a 30 dias. Em seguida, os compositos submetidos aos testes in vitro foram caracterizados por espectroscopia de infravermelho. O procedimento de sintese mostrou-se eficaz na pro- ducao de compositos com diferentes fracoes volumetricas de particulas distribuidas homogeneamente pelo material. Os resultados dos testes in vitro revelaram a deposicao de uma camada de hidroxiapatita carbonatada (HCA) na superficie dos materiais, comprovando a bioatividade dos compositos. Foi ainda observado que a cinetica de deposicao da camada de HCA pode ser controlada pela fracao volumetrica da fase bioativa. Palavras-chave: Compositos, biomateriais, bioatividade, poli(metacrilato de metila), vidros bioativos. Bioactive Composites Obtained from Bioactive Glass Particles into Poly(Methyl Methacrylate) Abstract: Some bioceramics have the ability to bind to tissues but they show mechanical properties very different from the ones of natural tissues. This fact restricts the use of these materials in a wider range of applications. The goal of this research is to synthesize and characterize polymer matrices reinforced with bioactive glass particles that potentially can combine ability to bond to tissues (bioactivity), with mechanical properties comparable to damage tissues. The composites were produced by bulk polymerization of methyl methacrylate in the presence of bioactive glass particles and an initiator at 60oC. Bioactive glass particles were added to the monomer in several concentrations to modify the mechanical properties and bioactivity of the composites. The bioactivity of the materials was evaluated by in vitro tests performed at 37oC in a simulated body fluid for periods of time ranging from 1 hour to 30 days. The composites submitted to in vitro tests were characterized by infrared spectroscopy. The results revealed the deposition of a hidroxy- carbonate-apatite layer on the surface of the composites, confirming their bioactivity. It was also observed that the fraction of the bioactive phase in the composites can be used to control the overall kinetics of the bioactivity process.