Sílvia Gavinho

Dr. Sílvia Gavinho

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 October 2023 in Nanomaterials
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Journal Article
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Sílvia GavinhoSílvia Gavinho
Sílvia Gavinho
APAna Sofia Tomaz Teixeira Pádua
Ana Sofia Tomaz Teixeira Pádua
LHLaura Holz
Laura Holz
ISIsabel Sá-Nogueira
Isabel Sá-Nogueira
Jorge Carvalho SilvaJorge Carvalho Silva
Jorge Carvalho Silva
Manuel Pedro Fernandes GraçaManuel Pedro Fernandes Graça
Manuel Pedro Fernandes Graça
The non-surgical treatments are being required to reconstruct damaged tissue, prioritizing our body’s natural healing process. Thus, the use of bioactive materials such as bioactive glass has been studied to support the repair and restoration of hard and soft tissue. Thus, in this work Bioglass 45S5 was developed, adding 1 and 2%mol of SrO or MgO and the physical and biological properties were evaluated. The addition of MgO and SrO at the studied concentrations promoted the slight increase in non-bridging oxygens number, observed through the temperature shift in phase transitions to lower values compared to Bioglass 45S5. The insertion of the ions also showed a positive effect on Saos-2 cell viability, decreasing the cytotoxic of Bioglass 45S5. Besides the Ca/P ratio on the pellets surface demonstrating no evidence of higher reactivity between Bioglass 45S5 and Bioglass with Sr and Mg, micrographs show that at 24 h the Ca/P rich layer is denser than in Bioglass 45S5 after the contact with simulated body fluid. The samples with Sr and Mg show a higher antibacterial effect compared to Bioglass 45S5. The addition of the studied ions may benefit the biological response of Bioglass 45S5 in dental applications as scaffolds or coatings.

18 December 2022 in Nanomaterials
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Journal Article
Open access
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Sílvia GavinhoSílvia Gavinho
Sílvia Gavinho
APAna Sofia Tomaz Teixeira Pádua
Ana Sofia Tomaz Teixeira Pádua
ISIsabel Sá-Nogueira
Isabel Sá-Nogueira
Jorge Carvalho SilvaJorge Carvalho Silva
Jorge Carvalho Silva
João BorgesJoão Borges
João Borges
Manuel Pedro Fernandes GraçaManuel Pedro Fernandes Graça
Manuel Pedro Fernandes Graça
The main reason for the increased use of dental implants in clinical practice is associated with aesthetic parameters. Implants are also presented as the only technique that conserves and stimulates natural bone. However, there are several problems associated with infections, such as peri-implantitis. This disease reveals a progressive inflammatory action that affects the hard and soft tissues surrounding the implant, leading to implant loss. To prevent the onset of this disease, coating the implant with bioactive glasses has been suggested. In addition to its intrinsic function of promoting bone regeneration, it is also possible to insert therapeutic ions, such as cerium. Cerium has several advantages when the aim is to improve osseointegration and prevent infectious problems with dental implant placement. It promotes increased growth and the differentiation of osteoblasts, improves the mechanical properties of bone, and prevents bacterial adhesion and proliferation that may occur on the implant surface. This antibacterial effect is due to its ability to disrupt the cell wall and membrane of bacteria, thus interfering with vital metabolic functions such as respiration. In addition, its antioxidant effect reverses oxidative stress after implantation in bone. In this work, Bioglass 45S5 with CeO2 with different percentages (0.25, 0.5, 1, and 2 mol%) was developed by the melt-quenching method. The materials were analyzed in terms of morphological, structural, and biological (cytotoxicity, bioactivity, and antibacterial activity) properties. The addition of cerium did not promote structural changes to the bioactive glass, which shows no cytotoxicity for the Saos-2 cell line up to 25 mg/mL of extract concentration for all cerium contents. For the maximum cerium concentration (2 mol%) the bioactive glass shows an evident inhibitory effect for Escherichia coli and Streptococcus mutans bacteria. Furthermore, all samples showed the beginning of the deposition of a CaP-rich layer on the surface of the material after 24 h.

19 January 2023 in Materials
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Journal Article
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Sílvia GavinhoSílvia Gavinho
Sílvia Gavinho
APAna Sofia Tomaz Teixeira Pádua
Ana Sofia Tomaz Teixeira Pádua
ISIsabel Sá-Nogueira
Isabel Sá-Nogueira
Jorge Carvalho SilvaJorge Carvalho Silva
Jorge Carvalho Silva
João BorgesJoão Borges
João Borges
Manuel Pedro Fernandes GraçaManuel Pedro Fernandes Graça
Manuel Pedro Fernandes Graça
Polymeric membranes are widely used in guided bone regeneration (GBR), particularly in dentistry. In addition, bioactive glasses can be added to the polymers in order to develop a matrix that is osteoconductive and osteoinductive, increasing cell adhesion and proliferation. The bioactive glasses allow the insertion into its network of therapeutic ions in order to add specific biological properties. The addition of zinc into bioactive glasses can promote antibacterial activity and induce the differentiation and proliferation of the bone cells. In this study, bioactive glasses containing zinc (0.25, 0.5, 1 and 2 mol%) were developed and structurally and biologically characterized. The biological results show that the Zn-containing bioactive glasses do not present significant antibacterial activity, but the addition of zinc at the highest concentration does not compromise the bioactivity and promotes the viability of Saos-2 cells. The cell culture assays in the membranes (PCL, PCL:BG and PCL:BGZn2) showed that zinc addition promotes cell viability and an increase in alkaline phosphatase (ALP) production.

12 June 2025 in Gels
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Journal Article
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FTFaouzia Tayari
Faouzia Tayari
KNKais Iben Nassar
Kais Iben Nassar
JCJoão Ferreira Carvalho
João Ferreira Carvalho
Sílvia SoretoSílvia Soreto
Sílvia Soreto
IHImen Hammami
Imen Hammami
Manuel ValenteManuel Valente
Manuel Valente
In this study, BiBaO3 perovskite was successfully synthesized via the sol–gel method and thoroughly characterized to evaluate its structural, microstructural, dielectric, electrical, and magnetic properties. X-ray diffraction (XRD) confirmed the formation of a single-phase perovskite structure with high crystallinity. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) revealed a uniform grain morphology and elemental composition consistent with the intended stoichiometry. Dielectric measurements exhibited strong frequency-dependent behavior, suggesting potential for capacitive applications. The electrical conductivity displayed thermally activated behavior, indicative of semiconducting characteristics. Magnetic measurements showed weak ferromagnetic behavior at room temperature, an unusual observation for undoped BaBiO3-based systems. This magnetism may stem from subtle structural distortions or compositional variations introduced during synthesis. Comparison with previously reported studies underscores the significant influence of the synthesis route and microstructural features on the multifunctional properties of BiBaO3. Overall, the results highlight the promise of sol–gel-derived BiBaO3 as a candidate for multifunctional electronic and magnetic applications.

1 June 2021 in Journal of Non-Crystalline Solids
Verified
Journal Article
Closed access
Sílvia GavinhoSílvia Gavinho
Sílvia Gavinho
MGM.P.F. Graça
M.P.F. Graça
PPP.R. Prezas
P.R. Prezas
JKJ. Suresh Kumar
J. Suresh Kumar
BMB.M.G. Melo
B.M.G. Melo
MVM.A. Valente
M.A. Valente

Verified
Journal Article
Open access
PDF file
IHImen Hammami
Imen Hammami
Sílvia GavinhoSílvia Gavinho
Sílvia Gavinho
Suresh Kumar JakkaSuresh Kumar Jakka
Suresh Kumar Jakka
Manuel ValenteManuel Valente
Manuel Valente
Manuel Pedro Fernandes GraçaManuel Pedro Fernandes Graça
Manuel Pedro Fernandes Graça
João BorgesJoão Borges
João Borges
Biofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into 45S5 Bioglass®. By combining the regenerative properties of Bioglass® with the antimicrobial effects of copper, this material has the potential to prevent infections, enhance osseointegration and improve the long-term success of implants. Bioglasses modified with various concentrations of CuO (from 0 to 8 mol%) were prepared with the melt-quenching technique. Structural analysis using Raman and FTIR spectroscopies did not reveal significant alterations in the bioglasses structure with the addition of Cu. The antibacterial activity of the samples was assessed against Gram-positive and Gram-negative bacteria, and the results demonstrated significant inhibition of bacterial growth for the bioglass with 0.5 mol% of CuO. Cell viability studies indicated that the samples modified with up to 4 mol% of CuO maintained good cytocompatibility with the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the bioactivity assessment demonstrated the formation of a calcium phosphate (CaP)-rich layer on the surfaces of all bioglasses within 24 h. Our findings show that the inclusion of copper in the bioglass offers a significant enhancement in its potential as a coating material for implants, resulting in notable advancements in both antibacterial efficacy and osteointegration properties.