Structure-property correlation and antimicrobial effect of the addition of semiconductors in acrylic resins

Author(s)

Beatriz Danieletto Sahm

• Document type: Master's Dissertation
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Ribeirão Preto (PCARP/BC)
• Defense date: 2023-07-03

Examining board members

Andréa Candido dos Reis; Regina Guenka Palma Dibb; Ana Carolina Pero; Camila Tirapelli

• Advisor: Andréa Candido dos Reis

Abstract

Biofilm formation on prosthesis surfaces can lead to local diseases as well as systemic diseases. These factors limit the longevity of the rehabilitative treatment and the quality of life of patients. However, it is desirable to provide a material that promotes antimicrobial capacity, providing a reduction in the accumulation of microorganisms and ideal physicochemical and mechanical properties. Due to the antimicrobial potential of silver vanadate (-AgVO3) and reduced graphene oxide (OGr), this study proposed the development of polymethylmethacrylate-based materials incorporated with antimicrobials to make prostheses and evaluate them regarding antimicrobial activity and physicochemical and mechanical properties. The minimum inhibitory concentration (MIC) of the materials was initially evaluated against Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus mutans species. Next, specimens were made of self-cured (A) and heat-cured (T) acrylic resin and divided into groups G1 (Resin A + &beta;-AgVO3); G2 (Resin A + OGr); G3 (Resin T + &beta;-AgVO3); G4 (Resin T + OGr). Antimicrobial properties were evaluated by XTT reduction method, colony forming unit (CFU) count, confocal laser microscopy (MCL) and scanning electron microscopy (SEM). Microstructural characterization was performed by SEM, energy dispersive elemental analysis (EDS) and differential scanning calorimetry (DSC). Physicochemical and mechanical tests evaluated flexural strength, roughness, hardness, wettability, sorption and solubility, porosity, mass loss by acid challenge, inductively coupled plasma mass spectrometry (ICP-MS) and UV/visible spectrometry. The data were statistically analyzed depending on their distribution pattern. Incorporation of &beta;-AgVO3 reduced the colonies of both microorganisms (p<0.05). The flexural strength and hardness of resins with &beta;-AgVO3 were not altered (p>0.05) and the incorporation of 0.5 of OGr in resin A presented better flexural values (p<0.05). It can be concluded that the group with 3% &beta;-AgVO3 showed the best antimicrobial efficacy. The incorporation of &beta;-AgVO3 maintained the mechanical properties of resins and favored the evaluated physicochemical properties. (AU)

• FAPESP's process: 22/01344-4 - Structure-property correlation and antimicrobial effect of semiconductor addition to acrylic resins
• Grantee: Beatriz Danieletto Sahm
• Support Opportunities: Scholarships in Brazil - Master