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Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers embedded with borate glasses of 45B5 composition doped with Co2+, Cu2+, and Zn2 +(46.1 B2O326.9-X CaO24.4 Na2O2.6 P2O5, X CoO/CuO/ZnO mol % (X = 0-5)) were produced by electrospinning for wound healing applications. Prior to their addition, the glasses exhibited two broad halos typical of a vitreous borate network, which were mainly composed of ring-type metaborate structural units. The particle distribution in the PHBV nanofibers embedded with 45B5 borate bioactive glasses is present in isolated and agglomerated states, being partially coated by a polymeric layer-except for the cobalt-doped glass, which resulted in a successful encapsulation with 100% embedding efficiency. The incorporation of the glasses reduced the PHBV crystallinity degree and its decomposition temperature, as well as its mechanical properties, including Young's modulus, tensile strength, and elongation at break. The neat PHBV fibers and those containing the cobalt-doped glasses demonstrated great cytocompatibility with human keratinocytes (HaCat), as suggested by the high cell viability after 7 days of exposure. Further studies are needed to fully understand the wound healing potential of these fibers, but our results significantly contribute to the area.

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Inorganic-organic hybrid biomaterials have been proposed for bone tissue repair, with improved mechanical flexibility compared with scaffolds fabricated from bioceramics. However, obtaining hybrids with osteoinductive properties equivalent to those of bioceramics is still a challenge. In this work, we present for the first time the synthesis of a class II hybrid modified with bioactive glass nanoparticles (nBGs) with osteoinductive properties. The nanocomposite hybrids were produced by incorporating nBGs in situ into a polytetrahydrofuran (PTHF) and silica (SiO2) hybrid synthesis mixture using a combined sol-gel and cationic polymerization method. nBGs ~80 nm in size were synthesized using the sol-gel technique. The structure, composition, morphology, and mechanical properties of the resulting materials were characterized using ATR-FTIR, 29Si MAS NMR, SEM-EDX, AFM, TGA, DSC, mechanical, and DMA testing. The in vitro bioactivity and degradability of the hybrids were assessed in simulated body fluid (SBF) and PBS, respectively. Cytocompatibility with mesenchymal stem cells was assessed using MTS and cell adhesion assays. Osteogenic differentiation was determined using the alkaline phosphatase activity (ALP), as well as the gene expression of Runx2 and Osterix markers. Hybrids loaded with 5, 10, and 15% of nBGs retained the mechanical flexibility of the PTHF-SiO2 matrix and improved its ability to promote the formation of bone-like apatite in SBF. The nBGs did not impair cell viability, increased the ALP activity, and upregulated the expression of Runx2 and Osterix. These results demonstrate that nBGs are an effective osteoinductive nanoadditive for the production of class II hybrid materials with enhanced properties for bone tissue regeneration.

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Los vidrios bioactivos (VBa) son materiales biocerámicos que tienen una extensa aplicación en medicina y odontología. A causa de su contenido de calcio y fosfato son muy simi- lares a la hidroxiapatita del tejido óseo. Su biocompatibili- dad y bioactividad los hacen materiales muy útiles para ser aplicados en diferentes áreas de la práctica dental, tales como periodoncia, cirugía, odontología restauradora y endodoncia. En endodoncia los VBa están indicados para realizar protec- ciones pulpares directas, pulpotomías, desinfecciones y obtu- raciones del sistema de conductos radiculares. El objetivo del presente trabajo fue realizar una revisión de las propiedades biológicas de los VBa en relación a sus aplicaciones en en- dodoncia (AU)

Bioactive glasses (BGs) are bioceramic materials with extensive clinical applications in medicine and dentistry. Be- cause of their phosphate and calcium contents, they are like the hydroxyapatiteof bone tissue. Their biocompatibility and bioactivity make them very useful biomaterials in different areas of dental practice, such as periodontics, oral surgery, restorative dentistry, and endodontics. In endodontics, bioac- tive glasses are indicated for direct pulp capping, pulpoto- mies, disinfections and fillings of the root canal system. The aim of this work was to carry out a review of the biological properties of BGs in relation to its application in endodontics (AU)

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OBJECTIVE: To determine the effect of airborne particle abrasion (APA) on micro-tensile bond strength (µTBS) to dentin using different air-abrasion/polishing powders. METHODS: The bonding effectiveness of G2 Bond Universal (G2B), used in etch-and-rinse (E&R) and self-etch mode (SE), was tested on bur-cut dentin and dentin air abraded/polished using six different powders (aluminum oxide 29 µm (AO29) and 53 µm (AO53), aluminum trihydroxide (AT), sodium bicarbonate (SB), sodium bicarbonate soft (SBsoft) and bioactive glass (BG); Velopex). Adhesive-composite resin specimens were immersed in distilled water at 37 °C for one week and cut into microspecimens. Half of the specimens were subjected to 50,000 thermocycles (aged). Immediate and aged µTBS to dentin were measured. Statistical analysis was performed using linear mixed-effects (LME) modeling (p < 0.05). RESULTS: Comparing the aged bond strengths to air-abraded/polished dentin with bur-cut dentin, pretreatment with SB and SBsoft in combination with G2B used in E&R mode, and BG air polishing in combination with both application modes (E&R, SE), resulted in a significantly higher bond strength. Dentin bond strength was only significantly lower when air abraded with AO29 and using G2B in SE mode. Aging did not significantly influence bond strength for both application modes (E&R, SE), except for AO29 and AT-treated dentin, where bond strengths decrea sed significantly using G2B in SE mode. In general, G2B reached significantly higher bond strengths on air-abraded/polished dentin in E&R mode than in SE mode. CONCLUSION: Air-abrasion/polishing did not impair dentin bond strength using G2B, except when dentin was air abraded with AO29 and using G2B in SE mode. Air polishing positively influenced the bond strength to dentin in specific groups. CLINICAL SIGNIFICANCE: APA is safe concerning bonding to dentin. The E&R application mode is preferred using G2B as adhesive on air-abraded/polished dentin. Air polishing with BG positively influenced dentin bond strength for both application methods.

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AIM: To evaluate the influence of an experimental solution of cobalt-doped F18 bioactive glass (F18Co) on tissue repair following regenerative endodontic procedure (REP) in rat molars. METHODOLOGY: The F18Co solution was prepared at a ratio of 1:5 F18Co powder to distilled water. The right or left upper first molars of 12 Wistar rats were used, where the pulps were exposed, removed, and irrigated with 2.5% sodium hypochlorite (NaOCl), followed by 17% ethylenediaminetetraacetic acid (EDTA) (5 min each). Subsequently, the molars were divided into two groups (n = 6): REP-SS and REP-F18Co, where they received a final irrigation (5 min) with saline solution (SS) or F18Co solution, respectively. Then, intracanal bleeding was induced, and the tooth was sealed. Untreated molars were used as controls (n = 3). At 21 days, the rats were euthanized, and the specimens were processed for analysis of mineralized tissue and soft tissue formation inside the root canal using haematoxylin-eosin. The presence and maturation of collagen were evaluated by Masson's trichrome and picrosirius red staining. Immunolabelling analyses of proliferating cell nuclear antigen (PCNA) and osteocalcin (OCN) were performed. The data were submitted to the Mann-Whitney U-test (p < .05). RESULTS: There was a similar formation of mineralized tissue in thickness and length in REP-SS and REP-F18Co groups (p > .05). Regarding the presence of newly formed soft tissue, most specimens of the REP-F18Co had tissue formation up to the cervical third of the canal, whilst the REP-SS specimens showed formation up to the middle third (p < .05), and there was higher maturation of collagen in REP-F18Co (p < .05). The number of PCNA-positive cells found in the apical third of the root canal was significantly higher in the F18Co group, as well as the OCN immunolabelling, which was severe in most specimens of REP-F18Co, and low in most specimens of REP-SS. CONCLUSION: The final irrigation with F18Co bioactive glass solution in REP did not influence mineralized tissue formation but induced soft tissue formation inside the root canals, with higher collagen maturation, and an increase in PCNA-positive cells and OCN immunolabelling.

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OBJECTIVES: To evaluate the effect of bromelain associated with Biosilicate on the bond strength (BS) of a universal adhesive system to sound (SD) and caries-affected dentin (CAD), and on the proteolytic activity. MATERIALS AND METHODS: Cavities were prepared in 360 molars, half submitted to cariogenic challenge. Teeth were separated into groups (n=20): Control-No treatment; CHX-0.12% chlorhexidine; NaOCl-5% sodium hypochlorite; Br5%-5% bromelain; Br10%-10% bromelain; Bio-10% Biosilicate; NaOClBio-NaOCl+Bio; Br5%Bio-Br5%+Bio; Br10%Bio-Br10%+Bio. Following treatments, the adhesive system was applied, and cavities were restored. Samples were sectioned into sticks and stored at 37 °C for 24 h, 6 months, and 1 year. Microtensile BS (2-way ANOVA, Bonferroni's test, α=0.05), fracture patterns (SEM), and adhesive interfaces (TEM) were evaluated. Bacterial collagenase assay and in situ zymography were performed. RESULTS: In CAD, Br10% presented higher BS (p=0.0208) than Br5%Bio. Br5% presented higher BS (p=0.0033) after 6 months than after 24 h; and association of treatments, higher BS (p<0.05) after aging than after 24 h. Mixed fractures were the most prevalent. Association of treatments promoted a more uniform hybrid layer with embedded Bio particles. Experimental groups presented lower (p<0.0001) relative fluorescence units than Control. Bromelain, associated or not with Bio, showed collagenolytic degradation. CONCLUSIONS: Bromelain associated with Biosilicate did not affect the BS to SD. In CAD, Br5%Bio decreased immediate BS but had no long-term influence. This association decreased the proteolytic activity. CLINICAL RELEVANCE: Bromelain and Biosilicate may enhance the longevity of adhesive restorations by inhibiting endogenous proteases.

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O tecido ósseo, embora tenha a capacidade de regeneração, é limitado em sua eficácia diante de defeitos críticos que impedem a regeneração natural. Dessa forma, materiais como a hidroxiapatita (HA) têm sido considerados promissores na engenharia de tecido ósseo. Contudo, apesar de sua ampla utilização, a hidroxiapatita apresenta desvantagens, como a taxa de reabsorção e remodelação lenta. Em contraste, o biovidro 45S5 se destaca por sua biocompatibilidade, propriedades bioativas e degradabilidade. Este estudo objetivou avaliar o comportamento biológico in vitro e in vivo de grânulos de vidro bioativas de biovidro 45S5 fabricadas pelo método de fusão. Os biovidros foram caracterizados por meio da difração de raios X (DRX), espectroscopia de infravermelho por transformação de Fourier (FTIR), calorimetria diferencial de varredura (DSC) e espectrometria de emissão óptica com plasmas indutivamente acoplados (ICP OES). Em seguida, foi realizado o estudo in vitro, utilizando células osteoblásticas isoladas de fêmures de ratos, que foram submetidas a análise da morfologia celular (MEV), viabilidade celular (MTT), conteúdo de proteína total (PT), atividade de fosfatase alcalina (ALP) e formação de nódulos de mineralização. No estudo in vivo, foram realizados defeitos ósseos críticos de 7 mm na tíbia de coelhos da raça New Zealand, que foram divididos em dois grupos (n=6) de acordo com o material de preenchimento: hidroxiapatita comercial (HA) e biovidro 45S5 (BG45S5). Após 2, 8 e 12 semanas, os animais foram eutanasiados e as peças ósseas foram submetidas as análises histológicas e histomorfométricas. Os dados foram submetidos ao teste de normalidade Shapiro-Wilk (p=0,05) e quando normais realizamos o teste t de student e quando não normais realizamos o teste de Mann-Whitney. Os resultados dos testes físico-químicos mostraram sucesso na produção do novo biomaterial. Nos testes in vitro, observou-se que o grupo BG45S5 não apresentou citotoxicidade e mostrou-se promissor com diferença estatisticamente significante em relação ao grupo hidroxiapatita comercial (p=0.0263). Nos testes de PT, ALP e nódulos de mineralização, os grupos não apresentaram diferença estatística entre eles (p<0,05). Contudo, o grupo BG45S5 mostrou-se promissor em relação aos outros grupos. Na análise histológica, ambos os grupos apresentaram neoformação óssea nos defeitos após 2, 8 e 12 semanas. Na histomorfometria, observou-se que os grupos BG45S5 e HA apresentaram maior área de neoformação óssea em 12 semanas. Houve diferença estatisticamente significante entre os grupos no tempo de 2 semanas, com maior neoformação para o grupo BG45S5. Apesar dos resultados promissores do grupo BG45S5, não houve diferença estatisticamente significativa entre os grupos (p<0,05) nos tempos de 8 e 12 semanas. Em resumo, os resultados evidenciaram o sucesso na produção do biomaterial sintético e o potencial do biomaterial BG45S5 como um material promissor para tratamento de defeitos ósseos críticos. (AU)

Bone tissue, despite its capacity of regeneration, is limited in its effectiveness when faced with critical defects that prevent natural regeneration. Therefore, materials such as hydroxyapatite (HA) have been considered promising in bone tissue engineering. However, despite its wide use, hydroxyapatite has disadvantages, such as slow resorption and remodeling rates. In contrast, 45S5 bioglass stands out for its biocompatibility, bioactive properties and degradability. This study aimed to evaluate the in vitro and in vivo biological behavior of bioactive 45S5 bioglass beads manufactured by the melt quenched method. The bioglasses were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and inductively coupled plasma optical emission spectrometry (ICP OES). Following this, an in vitro study was conducted using osteoblastic cells isolated from rat femurs, which were subjected to analysis of cell morphology (SEM), cell viability (MTT), total protein content (TP), alkaline phosphatase activity (ALP) and mineralization nodule formation. In the in vivo study, critical bone defects of 7 mm were created in the tibia of New Zealand rabbits, which were divided into two groups (n=6) according to the filling material: commercial hydroxyapatite (HA) and bioactive glass 45S5 (BG45S5). After 2, 8, and 12 weeks, the animals were euthanized and the bone pieces were subjected to histological and histomorphometric analyses. Data were subjected to the Shapiro-Wilk normality test (p=0.05), and when normal, we performed the Student's t-test, and when non-normal, we performed the Mann-Whitney test. The results of the physicochemical tests showed success in the production of the new biomaterial. In the in vitro tests, it was observed that the BG45S5 group did not present cytotoxicity and showed promise with a statistically significant difference compared to the commercial hydroxyapatite group (p=0.0263). In the TP, ALP and mineralization nodule tests, the groups showed no statistical difference between them (p<0.05). However, the BG45S5 group showed promise compared to the other groups. In the histological analysis, both groups showed new bone formation in the defects after 2, 8, and 12 weeks. In the histomorphometric analysis, it was observed that the BG45S5 and HA groups presented a larger area of new bone formation at 12 weeks. There was a statistically significant difference between the groups at 2 weeks, with greater new formation for the BG45S5 group. Despite the promising results of the BG45S5 group, there was no statistically significant difference between the groups (p<0.05) at 8 and 12 weeks. In summary, the results evidenced the successful production of the synthetic biomaterial and the potential of the BG45S5 bioglass as a promising material for treating critical bone defect.(AU)

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BACKGROUND: The aim of this study is to evaluate the outcome of patients with cavitary chronic osteomyelitis undergoing adjuvant treatment with bioactive glass (BAG) S53P4 and identify the independent risk factors (RFs) for recurrence in 6- and 12-month patient follow-up. METHODS: A retrospective, multicentre observational study conducted in tertiary specialised hospitals among patients undergoing the surgical treatment of chronic cavitary osteomyelitis using BAG-S53P4 in a granule and/or putty formulation to assess the clinical outcome and RFs for failure in 6- and 12-month patient follow-up. RESULTS: Of the 92 and 78 patients with 6-month and 12-month follow-ups, infection was eradicated in 85.9% and 87.2%, respectively. In the 6-month follow-up, BAG-S53P4 in the granule formulation presented a greater risk of recurrence compared to the bioactive glass putty formulation or combined granules and putty (prevalence ratio (PR) = 3.04; confidence interval 95% [CI95%]: 1.13-10.52) and neoplasia (PR = 5.26; CI95%: 1.17-15.52). In the 12-month follow-up cohort of 78 patients, smoking (PR = 4.0; 95% CI: 1.03-15.52) and nonfermenting GNB infection (PR = 3.87; CI95%: 1.09-13.73) presented a greater risk of recurrence. CONCLUSIONS: BAG-S53P4 is a viable option for bone-void filling and the treatment of chronic cavitary osteomyelitis. Formulations of BAG with putty or in combination with granules showed better results.

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Bioactive glasses (BGs) can potentially be applied in biomedicine, mainly for bone repair and replacement, given their unique ability to connect to natural bone tissue and stimulate bone regeneration. Since their discovery, several glass compositions have been developed to improve the properties and clinical abilities of traditional bioactive glass. Different inorganic ions, such as strontium (Sr2+), have been incorporated in BG due to their ability to perform therapeutic functions. Sr2+ has been gaining prominence due to its ability to stimulate osteogenesis, providing an appropriate environment to improve bone regeneration, in addition to its antibacterial potential. However, as there are still points in the literature that are not well consolidated, such as the influence of ionic concentrations and the BG production technique, this review aims to collect information on the state of the art of the biological behavior of BGs containing Sr2+. It also aims to gather data on different types of BGs doped with different concentrations of Sr2+, and to highlight the manufacturing techniques used in order to analyze the influence of the incorporation of this ion for bone regeneration purposes.

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The objective of this study was to investigate the osteogenic and antimicrobial effect of bioactive glass S53P4 incorporated into ß-tricalcium phosphate (ß-TCP) scaffolds in vitro and the bone neoformation in vivo. ß-TCP and ß-TCP/S53P4 scaffolds were prepared by the gel casting method. Samples were morphologically and physically characterized through X-ray diffraction (XRD) and scanning electron microscope (SEM). In vitro tests were performed using MG63 cells. American Type Culture Collection reference strains were used to determine the scaffold's antimicrobial potential. Defects were created in the tibia of New Zealand rabbits and filled with experimental scaffolds. The incorporation of S53P4 bioglass promotes significant changes in the crystalline phases formed and in the morphology of the surface of the scaffolds. The ß-TCP/S53P4 scaffolds did not demonstrate an in vitro cytotoxic effect, presented similar alkaline phosphatase activity, and induced a significantly higher protein amount when compared to ß-TCP. The expression of Itg ß1 in the ß-TCP scaffold was higher than in the ß-TCP/S53P4, and there was higher expression of Col-1 in the ß-TCP/S53P4 group. Higher bone formation and antimicrobial activity were observed in the ß-TCP/S53P4 group. The results confirm the osteogenic capacity of ß-TCP ceramics and suggest that, after bioactive glass S53P4 incorporation, it can prevent microbial infections, demonstrating to be an excellent biomaterial for application in bone tissue engineering.

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Bisphosphonates are a class of drugs that induce bone cancer cell death and favor bone regeneration, making them suitable for bone cancer treatment. However, when combined with bioactive glasses to enhance bone regeneration, a chemical bond between biphosphonates and the glass surface inactivates their mechanism of action. A new colloidal hydrogel-based drug delivery system could overcome that limitation once bisphosphonates, such as zoledronic acid (ZA), are incorporated into hydrogel micelles, avoiding their interaction with the glass surface. In this work, we proposed formulations based on a poloxamer 407 thermo-responsive hydrogel matrix containing holmium-doped bioactive glass nanoparticles and different concentrations (0.05 and 5 mg/mL) of ZA. We characterized the influence of the glass and the ZA on the hydrogel properties. In addition, a drug concentration screening was performed, and biological characterizations evaluated the best result. The biological characterization consisted of evaluating cytotoxicity and in vitro bone regeneration ability through cell migration and quantification of genes related to osteogeneses through RT-PCR. The results suggest that the addition of glasses and ZA to the poloxamer did not significantly influence the sol-gel transition of the hydrogels (around 13 °C) regardless of the ZA content. However, the ZA at high concentration (PL-ZA100) decreased the enthalpy of gel formation from 68 to 43 kJ.mol-1 when compared with the pure hydrogel formulation (PL), suggesting a water structurer role of ZA, which is withdrawn when glass particles are added to the system (PL-BG5Ho-ZA100). Solid-state 31P nuclear resonance spectroscopy results showed that part of the ZA is chemically bonded to the glass surface, which explains the withdrawal in the water structurer role of ZA when the glasses were incorporated into the hydrogel. Besides, based on the drug release results, we proposed a model where part of the ZA is "free," encapsulated in the hydrogel matrix, while another part of the ZA is bonded to the glass surface. Finally, considering the in vitro results and our proposed model, the ratio between "free" and "bonded" ZA in our drug delivery systems showed in vitro evidence of a cancer treatment that selectively kills osteosarcoma cells while still favoring an osteogenic microenvironment. By overcoming the limitation of combining bisphosphonates with bioactive glasses, hydrogel-based drug delivery systems can be a solution for the development of new formulations proposed for bone cancer treatment in conjunction with bone regeneration.

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Abstract This study evaluated the effect of phytosphingosine (PHS) and bioactive glass-ceramic (Biosilicate) on dental enamel in terms of color alteration (ΔE), microhardness, and surface roughness when submitted to erosive challenge (EC). Sixty specimens of bovine teeth (6×6×2mm) were obtained. Initial color (Easyshade, VITA), KHN (HMV-2, Shimadzu), and Ra (SJ-201P, Mitutoyo) measurements were performed. Specimens were separated into groups according to treatments: PHS, 10% Biosilicate, PHS+10% Biosilicate, and artificial saliva (control) and submitted to EC with Coca-Cola for 2 min. This cycle was repeated 4 times daily/15 days. Between cycles, specimens remained in artificial saliva (2 h/37°C). After daily cycles, they were also stored in artificial saliva at 37ºC. Final color, microhardness, and surface roughness measurements were done. Color and KHN data were analyzed by one-way ANOVA, Tukey's test; and Ra, by 2-way ANOVA, repeated measures, and Tukey's test (p<.05). The highest ΔE occurred in Saliva+EC (p<.05). Groups treated with PHS presented lower color change than Saliva+EC (p<.05). All the groups presented mean values above the 50:50% perceptibility (50:50%PT) and acceptability (50:50%AT) thresholds, except for control that showed mean value above 50:50%PT but below 50:50%AT. Biosilicate+EC showed higher relative microhardness than Saliva+EC (p<.05), but was similar to PHS+EC and PHS+Biosilicate+EC. Final enamel surface roughness increased for all the groups (p<.05), except for the control. The Biosilicate may prevent enamel mineral loss induced by erosion better than saliva. The PHS associated or not to Biosilicate demonstrated better color stability than saliva.

Resumo Este estudo avaliou o efeito da Fitoesfingosina (PHS) e da vitrocerâmica bioativa (Biosilicato) sobre o esmalte dental em termos de alteração de cor (ΔE), microdureza (KHN) e rugosidade superficial, quando submetido a desafio erosivo (DE). Sessenta espécimes de dentes bovinos (6×6×2mm) foram obtidos. Foram realizadas leituras de cor inicial (Easyshade, VITA), microdureza (HMV-2, Shimadzu) e rugosidade superfícial (SJ-201P, Mitutoyo). Os espécimes foram separados em grupos de acordo com os tratamentos: PHS, Biosilicato a 10%, PHS+Biosilicato a 10%, e saliva artificial (controle). Em seguida, foram submetidos a DE com Coca-Cola por 2 min. Esse ciclo foi repetido 4 vezes/dia por 15 dias. Entre os ciclos, as amostras foram mantidas em saliva artificial (2 h/37°C). Após os ciclos diários, os espécimes também foram armazenados em saliva artificial a 37ºC. Foram realizadas leituras finais de cor, microdureza e rugosidade superficial. Os dados de cor e microdureza foram analisados ​​por ANOVA de uma via, teste de Tukey; e dados de rugosidade superficial, por ANOVA de duas vias, teste de Tukey (p<.05). A maior ΔE ocorreu em Saliva+DE (p<.05). Grupos tratados com PHS apresentaram menor alteração de cor do que Saliva+DE (p<.05). Biosilicate+DE demonstrou valores intermediários, similar (p>.05) aos outros grupos, exceto Saliva+DE. Todos os grupos presentaram média acima dos limites 50:50% de perceptibilidade (50:50%LP) e aceitabilidade (50:50%LA) exceto o controle que demonstrou média acima do 50:50%LA mas abaixo do 50:50%LP. Biosilicate+DE mostrou maior microdureza realativa do que Saliva+DE (p<.05), mas similar a PHS+DE e PHS+Biosilicato+DE. A rugosidade de superfície do esmalte aumentou para todos os grupos, exceto para o controle que presentou a menor alteração (p<.05). O Biosilicato apode prevenir perda mineral do esmalte indizido pela erosão melhor que a saliva. O PHS associado ou não ao Biosilicato demonstrou melhor estabilidade de cor que a saliva.

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Objective: Evaluating the clinical results of bioactive glass S53P4 putty for the treatment of cavitary chronic osteomyelitis. Methods: Retrospective observational study, including patients of any age with clinical and radiological diagnosis of chronic osteomyelitis, who underwent surgical debridement and implantation of bioactive glass S53P4 putty (BonAlive® Putty, Turku, Finland). Patients who underwent any plastic surgery on the soft tissues of the affected site or had segmental bone lesions or septic arthritis were excluded. Statistical analysis was performed using Excel®. Demographic data, as well as data on the lesion, treatment, and follow-up, were collected. Outcomes were classified as "disease-free survival," "failure," or "indefinite." Results: This study included 31 patients, of which 71% were men and had with a mean age of 53.6 years (SD ± 24.2). In total, 84% were followed-up for at least 12 months and 67.7% had comorbidities. We prescribed combination antibiotic therapy for 64.5% of patients. In 47.1%, Staphylococcus aureus was isolated. Finally, we classified 90.3% of cases as "disease-free survival" and 9.7% as "indefinite." Conclusion: Bioactive glass S53P4 putty is safe and effective to treat cavitary chronic osteomyelitis, including infections by resistant pathogens, such as methicillin-resistant S. aureus. Level of Evidence IV, Case Series.

Objetivo: Avaliar a atividade do vidro bioativo S53P4 em pasta no tratamento de osteomielite crônica. Métodos: Estudo observacional retrospectivo, com inclusão de indivíduos de qualquer idade com diagnóstico clínico e radiológico de osteomielite que realizaram tratamento cirúrgico com limpeza e desbridamento, seguido do preenchimento da cavidade com biovidro S53P4 em pasta (BonAlive ® Putty, Turku, Finland). Foram excluídos pacientes submetidos a procedimentos de cirurgia plástica nos tecidos moles do local afetado, com lesões ósseas segmentares e com presença de artrite séptica. A análise estatística foi realizada em Excel ® . Foram coletados dados demográficos, sobre a lesão, o tratamento e o acompanhamento. O desfecho foi classificado em "sobrevida livre de doença", "falha" ou "indeterminado". Resultados: Dos 31 pacientes analisados, 71% eram homens, com idade média de 53,6 anos (DP ± 24,26). Do total, 84% foram acompanhados por no mínimo 12 meses, e 67,7% apresentaram comorbidades. A terapia antibiótica combinada foi realizada em 64,5% dos pacientes, sendo o patógeno mais frequente o Staphylococcus aureus (47,1%). Ao final, 90,3% dos pacientes obtiveram "sobrevida livre de doenças" e 9,7% foram considerados "indeterminados". Conclusão: O vidro bioativo S53P4 em pasta é seguro e eficaz no tratamento da osteomielite cavitária e de infecções por patógenos resistentes, incluindo o S. aureus multirresistente. Nível de Evidência IV, Série de Casos.

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Bone infection treatment is a significant challenge for the orthopedic field. 3D printing is a promising technology to produce scaffolds with customized architecture, able to stimulate and support bone growth. ß-TCP and S53P4 bioactive glass (BG) are well-known biomaterials for scaffold manufacturing. However, a multifunctional scaffold, able to inhibit microbial proliferation at the defect site, is of increasing interest to avoid infection recurrence. Tea tree oil (TTO) has aroused interest as an antimicrobial agent to minimize the use of antibiotics. Therefore, combining the regenerative potential of a bioceramic with TTO's antimicrobial properties could result in a scaffold capable of stimulating tissue growth and treating infections. In this context, this study aimed to produce and characterize 3D-printed ß-TCP/S53P4 BG scaffolds coated with TTO. Scaffolds morphological and chemical characterizations were carried out through XDR, SEM, and FTIR analysis. ß-TCP/S53P4 BG scaffolds showed a compressive strength of ~2 MPa and 53 ± 2% of porosity. The scaffolds were coated by two different procedures, using an ethanol/TTO (EtOH/TTO) and a gelatin/TTO (Gel/TTO) solution with 5, 10, and 15% (v/v) TTO. The addition of TTO decreased MG-63 cell viability for both coating groups, but the Gel/TTO group showed higher cell viability. The antibacterial activity of the coated scaffolds was evaluated against S. aureus and higher inhibition of colony formation was found for Gel/TTO group. Therefore, the coating with Gel/TTO was effective in terms of antibacterial activity and cell viability. Such Gel/TTO coated ß-TCP/S53P4 BG scaffolds are proposed for antibacterial bone tissue engineering.

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OBJECTIVES: To evaluate hydrogel-based scaffolds embedded with parathyroid hormone (PTH)-loaded mesoporous bioactive glass (MBG) on the enhancement of bone tissue regeneration in vitro. MATERIALS AND METHODS: MBG was produced via sol-gel technique followed by PTH solution imbibition. PTH-loaded MBG was blended into the hydrogels and submitted to a lyophilisation process associated with a chemical crosslinking reaction to the production of the scaffolds. Characterisation of the MBG and PTH-loaded MBG scaffolds, including the scanning electron microscope (SEM) connected with an X-ray detector (EDX), Fourier transform infrared (FTIR), compression strength, rheological measurements, swelling and degradation rates, and PTH release analysis, were performed. Also, bioactivity using simulated-body fluid (SBF), biocompatibility (MTT), and osteogenic differentiation analyses (von Kossa and Alizarin Red stainings, and µ-computed tomography, µCT) of the scaffolds were carried out. RESULTS: SEM images demonstrated MBG particles dispersed into the hydrogel-based scaffold structure, which was homogeneously porous and well interconnected. EDX and FTIR revealed large amounts of carbon, oxygen, sodium, and silica in the scaffold composition. Bioactivity experiments revealed changes on sample surfaces over the analysed period, indicating the formation of carbonated hydroxyapatite; however, the chemical composition remained stable. PTH-loaded hydrogel-based scaffolds were biocompatible for stem cells from human-exfoliated deciduous teeth (SHED). A high quantity of calcium deposits on the extracellular matrix of SHED was found for PTH-loaded hydrogel-based scaffolds. µCT images showed MBG particles dispersed into the scaffolds' structure, and a porous, lamellar, and interconnected hydrogel architecture. CONCLUSIONS: PTH-loaded hydrogel-based scaffolds demonstrated consistent morphology and physicochemical properties for bone tissue regeneration, as well as bioactivity, biocompatibility, and osteoinductivity in vitro. Thus, the scaffolds presented here are recommended for future studies on 3D printing. CLINICAL RELEVANCE: Bone tissue regeneration is still a challenge for several approaches to oral and maxillofacial surgeries, though tissue engineering applying SHED, scaffolds, and osteoinductive mediators might help to overcome this clinical issue.

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O avanço no campo da engenharia tecidual e biomateriais conduz ao aprimoramento dos tratamentos e tecnologias já existentes, visando otimizar a resolução de injúrias e permitir tratamentos cada vez mais eficientes para a população. Desta maneira, o objetivo deste estudo foi produzir e caracterizar scaffolds de policaprolactona (PCL) incorporadas com três formulações diferentes de vidro bioativo, bem como avaliar a influência destas na osteogênese in vitro e na neoformação óssea in vivo. Para isso, foram obtidos quatro grupos experimentais: PCL (P), PCL incorporado com o vidro bioativo 45S5 (P45), PCL incorporado com o vidro bioativo S53P4 (P53) e PCL incorporado com o vidro bioativo 58S (P58). A síntese de todos os vidros foi realizada pela rota Sol-Gel, os quais foram incorporados à solução de PCL previamente à produção dos scaffolds por meio do processo de eletrofiação. Posteriormente à caracterização morfológica e físico-química, os scaffolds foram submetidas aos testes biológicos in vitro e in vivo. Na etapa in vitro, células da medula óssea obtidas de fêmures de ratos foram isoladas e plaqueadas com os scaffolds, visando avaliar a influência destas na atividade e diferenciação celular na osteogênese. Para o ensaio in vivo, 30 ratos Wistar foram submetidos ao procedimento cirúrgico para confecção de um defeito crítico de 3,0 mm nas tíbias direita e esquerda para avaliação dos scaffolds. A eutanásia dos animais foi realizada após 4 semanas do procedimento cirúrgico, e as peças foram submetidas à análise histológica, imuno-histoquímica (IHC), histomorfométrica e ao teste biomecânico de flexão de três pontos. Os dados obtidos foram estatisticamente analisados pelo teste ANOVA um fator, com nível de significância adotado de 5%. A caracterização morfológica e físico-química evidenciou o sucesso da referida metodologia em confeccionar o novo biomaterial. Na análise in vitro, observou-se que os scaffolds não foram citotóxicos, e permitiram atividade e diferenciação celular, sendo que o grupo P exibiu maior conteúdo de proteína total (p<0,05) em ambos os períodos analisados, e os grupos P53 e P58 exibiram maior atividade de fosfatase alcalina (ALP), não diferindo entre si (p>0,0001) enquanto P exibiu menor atividade, diferindo estatisticamente (p<0,05). Todos os grupos permitiram a formação de nódulos de mineralização, e foi observado maior quantificação de Alizarina nos grupos P45, P53 e P58 quando comparados ao grupo P (p<0,05). Na análise histológica foi observada a presença de neoformação óssea na região do defeito crítico em todos os grupos. A IHC evidenciou a imunomarcação por osteocalcina (OC) e TRAP. Na análise histomorfométrica foi observada maior formação nos grupos P45 e P53, os quais não diferiram entre si (p>0,0001). O teste biomecânico evidenciou que não houve diferença estatisticamente significante entre os grupos (p>0,05) ao avaliar a força de ruptura das tíbias. Os resultados evidenciaram o sucesso na produção do novo compósito, sendo que os grupos contendo vidro bioativo, em especial o grupo P53, se mostraram mais osteoativos e osteocondutores quando comparado ao grupo P, e evidenciam o potencial uso na engenharia tecidual.(AU)

Advancements in the field of tissue engineering and biomaterials lead to the enhancement of existing treatments and technologies, aiming to optimize injury resolution and enable increasingly efficient treatments for the population. Thus, the objective of this study was to produce and characterize polycaprolactone (PCL) scaffolds incorporated with three different formulations of bioactive glass, as well as to evaluate their influence on in vitro osteogenesis and in vivo bone neoformation. To achieve this, four experimental groups were established: PCL (P), PCL incorporated with 45S5 bioactive glass (P45), PCL incorporated with S53P4 bioactive glass (P53), and PCL incorporated with 58S bioactive glass (P58). The synthesis of all glasses was carried out via the Sol-Gel route, and they were subsequently integrated into the PCL solution prior to scaffold production through the electrospinning process. Following morphological and physicochemical characterization, the scaffolds underwent in vitro and in vivo biological testing. In the in vitro phase, bone marrow cells obtained from rat femurs were isolated and plated with the scaffolds to assess their influence on cellular activity and differentiation in osteogenesis. For the in vivo assay, 30 Wistar rats underwent a surgical procedure to create a 3.0 mm critical defect in the right and left tibias for the evaluation of the scaffolds. Euthanasia of the animals was performed after 4 weeks of the surgical procedure, and the specimens were subjected to histological analysis, immunohistochemistry (IHC), histomorphometric analysis, and a three-point bending biomechanical test. The data obtained were statistically analyzed using a one-way ANOVA with a significance level set at 5%. Morphological and physicochemical characterization confirmed the success of the aforementioned methodology in fabricating the new biomaterial. In the in vitro analysis, it was observed that the scaffolds were not cytotoxic and allowed for cellular activity and differentiation. Group P exhibited a higher total protein content (p<0.05) in both analyzed periods, and groups P53 and P58 displayed greater alkaline phosphatase (ALP) activity, with no significant difference between them (p>0.0001), while P exhibited lower activity, differing statistically (p<0.05). All groups supported the formation of mineralization nodules, with a higher quantification of Alizarin observed in the P45, P53, and P58 groups compared to the P group (p<0.05). Histological analysis revealed the presence of bone neoformation in the critical defect region in all groups. IHC showed immunolabeling for osteocalcin (OC) and TRAP. Histomorphometric analysis revealed greater formation in the P45 and P53 groups, which did not differ from each other (p>0.0001). The biomechanical test indicated no statistically significant difference between the groups (p>0.05) when evaluating tibial rupture strength. The results demonstrated the success in producing the new composite, with the bioactive glass-containing groups, especially the P53 group, showing greater osteoactivity and osteoconductivity compared to the P group, highlighting their potential for use in tissue engineering (AU)

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O objetivo deste estudo foi desenvolver e avaliar um adesivo resinoso modificado com a incorporação de partículas de vidro bioativas (SCHOTT Bioactive Glass) em diferentes concentrações. Foram avaliados a resistência ao cisalhamento (RU), o índice de remanescente dentário (IRA), o grau de conversão (GC) e a liberação de cálcio. Foram utilizados 50 incisivos bovinos que foram fixados, através de suas raízes, em um molde de PVC, com resina acrílica autopolimerizável. As amostras foram alocadas em 5 grupos (n=10): TXT - Adesivo Transbond XT (3M Unitek, Monrovia, CA, EUA) sem adição de partículas de vidro bioativas, TXT20, TXT30, TXT50 ­ Adesivo Transbond XT acrescido respectivamente de 20%, 30% e 50% de partículas de vidro bioativas e SH - Adesivo resinoso FL BOND ll (SHOFU Inc.) com biomaterial SPRG. As amostras receberam uma profilaxia com pedra pomes e condicionamento com ácido fosfórico à 37%. Em seguida foi aplicada uma fina camada do sistema adesivo indicado na face vestibular dos incisivos bovinos, em todos os grupos e fotopolimerizado por 20 segundos, utilizando-se um fotopolimerizador RADII-Cal (SDI, Victoria, Austrália). Depois foi aplicada uma pequena quantidade de pasta resinosa fotopolimerizável Transbond XT (3M Unitek, Monrovia, CA, EUA) sobre a superfície dos bráquetes autoligados (MORELLI, Sorocaba, São Paulo, Brasil) e estes foram devidamente colados na face vestibular, no centro da coroa clínica do incisivo bovino e fotopolimerizado por 20 segundos, em cada face. Posteriormente as amostras foram submetidas ao teste de resistência ao cisalhamento. O índice de remanescente adesivo foi avaliado em estereomicroscópio DISCOVERY V20 (ZEISS). Os adesivos resinosos foram submetidos ao teste de grau de conversão e liberação de cálcio. Os dados foram inicialmente submetidos ao teste de normalidade e depois submetidos ao teste de ANOVA um fator, seguido do teste de Tukey para análise de comparações múltiplas, com nível de significância de 0,05. De acordo com os resultados obtidos na resistência de união ao cisalhamento (MPa±Dp) a maior média foi observada no grupo TXT 19,50±1,40A, seguida do grupo TXT20 18,22±1,04AB, seguida do grupo SH 17,62±1,45B, seguida do grupo TXT30 14,48±1,46C e a menor média TXT50 14,13±1,02C. No grau de conversão a maior média foi observada no grupo TXT20 73,02±3,33A que foi estatisticamente semelhante ao grupo SH 68,50±1,09A, seguida do grupo TXT 60,28±1,06B e TXT30 58,84±4,06B e a menor média foi do grupo TXT50 40,67±1,21C.Para a liberação de cálcio a maior média foi TXT50 2,23±0,11D, seguida por TXT30 0,74±0,00C, TXT20 0,55±0,00B, SH 0,47±0,04B e TXT 0,14±0,00A. Concluiu-se que a incorporação de partículas de vidro bioativas influenciou na resistência de união ao cisalhamento, no grau de conversão e na liberação de cálcio (AU).

The objective of this study was to develop and evaluate a resin adhesive modified with the incorporation of bioactive glass particles (SCHOTT Bioactive Glass) in different concentrations. Shear bond strength (SBS), adhesive remnant index (ARI), degree of conversion (DC) and calcium release were evaluated. Fifty bovine incisors were used, which were fixed through their roots in a PVC mold with self-curing acrylic resin. The samples were allocated into 5 groups (n=10): TXT ­ Transbond XT Adhesive (3M Unitek, Monrovia, CA, USA) without addition of bioactive glass particles, TXT20, TXT30, TXT50 ­ Transbond XT Adhesive rescpectively increased by 20%, 30% and 50% bioactive glass particles and SH ­ FL BOND ll resin adhesive (SHOFU Inc.) with SPRG biomaterial. The samples received prophylaxis with pumice stoe and conditioning with 37% phosphoric acid. Then, a thin layer of the indicated adhesive system was applied to the buccal surface of the bovine incisors, in all groups, and light cured for 20 seconds, using a RADII-Call curing light (SDI, Victoria, Australia). Then, a small amount of Transbond XT light-curing resinous paste (3M Unitek, Monrovia, CA, USA) was applied on the surface of the self-ligating brackets (MORELLI, Sorocaba, São Paulo, Brazil) and these were duly bonded on the buccal surface, in the center of the clinical crown of the bovine incisor and light cured for 20 seconds, on each side. Subsequently, the samples were submitted to the shear bond test. The adhesive remnant index was evaluated using a DISCOVERY V20 stereomicroscope (ZEISS). The resin adhesives were submitted to the degree of conversion and calcium release test. The data were initially submitted to the normality test and then submitted to the one-way ANOVA test, followed by the Tukey test for analysis of multiple comparisons, with a significance level of 0.05. According to the results obtained in the shear bond strength (MPa±Dp), the highest average was observed in the TXT group 19.50±1.40A, followed by the TXT20 group 18.22±1.04AB, followed by the SH group 17.62±1.45B, followed by the TXT30 group 14.48±1.46C and the lowest mean TXT5014.13±1.02C. In the degree of conversion, the highest average was observed in the TXT20 73.02±3.33A group, wich was statiscally like the SH group 68.50±1.09A, followed by the TXT 60.28±1.06B and TXT30 group 58.84±4.06B and the lowest mean was for the TXT50 group 40.67±1.21C. For calcium release, the highest mean was TXT50 2.23±0.11D, followed by TXT30 0.74±0.00C, TXT20 0.55±0.00B, SH 0.47±0.04B and TXT 0.14±0.00A. It was concluded that the incorporation of bioactive glass particles influenced in the shear bond strength, in the degree of conversion and in the release of calcium (AU).

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ABSTRACT Objective: Evaluating the clinical results of bioactive glass S53P4 putty for the treatment of cavitary chronic osteomyelitis. Methods: Retrospective observational study, including patients of any age with clinical and radiological diagnosis of chronic osteomyelitis, who underwent surgical debridement and implantation of bioactive glass S53P4 putty (BonAlive® Putty, Turku, Finland). Patients who underwent any plastic surgery on the soft tissues of the affected site or had segmental bone lesions or septic arthritis were excluded. Statistical analysis was performed using Excel®. Demographic data, as well as data on the lesion, treatment, and follow-up, were collected. Outcomes were classified as "disease-free survival," "failure," or "indefinite." Results: This study included 31 patients, of which 71% were men and had with a mean age of 53.6 years (SD ± 24.2). In total, 84% were followed-up for at least 12 months and 67.7% had comorbidities. We prescribed combination antibiotic therapy for 64.5% of patients. In 47.1%, Staphylococcus aureus was isolated. Finally, we classified 90.3% of cases as "disease-free survival" and 9.7% as "indefinite." Conclusion: Bioactive glass S53P4 putty is safe and effective to treat cavitary chronic osteomyelitis, including infections by resistant pathogens, such as methicillin-resistant S. aureus. Level of Evidence IV, Case Series.

RESUMO Objetivo: Avaliar a atividade do vidro bioativo S53P4 em pasta no tratamento de osteomielite crônica. Métodos: Estudo observacional retrospectivo, com inclusão de indivíduos de qualquer idade com diagnóstico clínico e radiológico de osteomielite que realizaram tratamento cirúrgico com limpeza e desbridamento, seguido do preenchimento da cavidade com biovidro S53P4 em pasta (BonAlive ® Putty, Turku, Finland). Foram excluídos pacientes submetidos a procedimentos de cirurgia plástica nos tecidos moles do local afetado, com lesões ósseas segmentares e com presença de artrite séptica. A análise estatística foi realizada em Excel ® . Foram coletados dados demográficos, sobre a lesão, o tratamento e o acompanhamento. O desfecho foi classificado em "sobrevida livre de doença", "falha" ou "indeterminado". Resultados: Dos 31 pacientes analisados, 71% eram homens, com idade média de 53,6 anos (DP ± 24,26). Do total, 84% foram acompanhados por no mínimo 12 meses, e 67,7% apresentaram comorbidades. A terapia antibiótica combinada foi realizada em 64,5% dos pacientes, sendo o patógeno mais frequente o Staphylococcus aureus (47,1%). Ao final, 90,3% dos pacientes obtiveram "sobrevida livre de doenças" e 9,7% foram considerados "indeterminados". Conclusão: O vidro bioativo S53P4 em pasta é seguro e eficaz no tratamento da osteomielite cavitária e de infecções por patógenos resistentes, incluindo o S. aureus multirresistente. Nível de Evidência IV, Série de Casos.

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Bone lesions affect individuals of different age groups, compromising their daily activities and potentially leading to prolonged morbidity. Over the years, new compositions and manufacturing technologies were developed to offer customized solutions to replace injured tissue and stimulate tissue regeneration. This work used digital light processing (DPL) technology for three-dimensional (3D) printing of porous structures using pre-ceramic polymer, followed by pyrolysis to obtain SiOC vitreous scaffolds. The SiOC scaffolds produced had an amorphous structure (compatible with glass) with an average porosity of 72.69% ± 0.99, an average hardness of 935.1 ± 71.0 HV, and an average maximum flexural stress of 7.8 ± 1.0 MPa, similar to cancellous bone tissue. The scaffolds were not cytotoxic and allowed adult stem cell adhesion, growth, and expansion. After treatment with osteoinductive medium, adult stem cells in the SiOC scaffolds differentiated to osteoblasts, assuming a tissue-like structure, with organization in multiple layers and production of a dense fibrous matrix rich in hydroxyapatite. The in vitro analyses supported the hypothesis that the SiOC scaffolds produced in this work were suitable for use as a bone substitute for treating critically sized lesions, with the potential to stimulate the gradual process of regeneration of the native tissue. The data obtained stimulate the continuity of studies with the SiOC scaffolds developed in this work, paving the way for evaluating safety and biological activity in vivo.

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To try to reduce the deleterious effects of tooth whitening, bioactive materials have been used. Forty enamel/dentin blocks were stained on dark tea and randomly assigned into four groups (n=10): control group (unbleached), HP35 % (35 % hydrogen peroxide), BG45S5 (Bioglass 45S5® incorporated into HP35 %), and BIO (Biosilicate® incorporated into HP35 %). Colorimetric analysis and microhardness evaluation was performed at baseline, 24 hours and 7 days after the final whitening session. Two-way ANOVA for repeated measures and Bonferroni test was used at a significance level of 5 %. All the coordinates (ΔL*, Δa*, Δb*, ΔE00 and WID) showed a difference between the control group and the experimental ones (p0.05), which suggest a color stability over a week. In contrast, after 7 days, the WID showed that control and PH35 % were different than the other groups (p 0.05). The microhardness did not change over time (p>0.05), except for 35 % HP. In conclusion Bioglass 45S5® and Biosilicate® prevented enamel damage without negatively affect the whitening efficacy.

Para intentar reducir los efectos nocivos del aclaramiento dental, se han usado materiales bioactivos. Cuarenta bloques de esmalte/dentina se tiñeron con té oscuro y se asignaron al azar en cuatro grupos (n=10): grupo de control (sin blanquear), HP35% (peróxido de hidrógeno al 35 %), BG45S5 (Bioglass 45S5® incorporado en HP35%) y BIO (Biosilicato® incorporado a HP35%). El análisis colorimétrico y la evaluación de la microdureza se realizaron al inicio del estudio, 24 horas y 7 días después de la última sesión de blanqueamiento. Se utilizó ANOVA de dos vías para medidas repetidas y la prueba de Bonferroni a un nivel de significancia del 5 %. Todas las coordenadas (ΔL*, Δa*, Δb*, ΔE00 y WID) mostraron diferencia entre el grupo control y el experimental (p0.05), lo que sugiere una estabilidad del color durante una semana. En cambio, a los 7 días, el WID mostró que el control y el PH35 % eran diferentes a los demás grupos (p 0.05). La microdureza no cambió con el tiempo (p>0.05), excepto para 35 % HP. En conclusión Bioglass 45S5® y Biosilicate® previnieron el daño del esmalte sin afectar negativamente la eficacia del blanqueamiento.