Evaluation of the physical-mechanical and microbiological properties of a new resin-modified glass-ionomer cement containing nanoparticles of sodium trimetaphosphate and phosphorylated chitosan: in vitro study.

Author(s)

Gabriela Leal Peres Fernandes

• Document type: Master's Dissertation
• Press: Araçatuba. 2023-04-05.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba
• Defense date: 2023-03-06
• Advisor: Marcelle Danelon; Alberto Carlos Botazzo Delbem

Abstract

Aim: To evaluate in vitro the effect of addition of sodium trimetaphosphate nano-sized particles (TMPnano) and phosphorylated chitosan (Chi-Ph) to resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation on mechanical, antimicrobial and cytotoxic properties. Material and Methods: Specimens (n=6) were made: 1) RMGIC without TMPnano/Qui-Ph (Control-Fuji Ortho LC); 2) RMGIC-14%TMPnano; 3) RMGIC-0.25%Qui-Ph; 4) RMGIC-0.5%Qui-Ph; 5) RMGIC-14%TMPnano-0.25%Qui-Ph and 6) RMGIC-14%TMPnano-0.5%Qui-Ph. The tensile and compressive strength, surface hardness and degree of conversion of the monomers were determined: RT; RC-MPa, SH- KNH, 24 hours/7 days. For fluoride (F) release, specimens were immersed in demineralizing (6 hours) and remineralizing (16 hours) solution. The antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism evaluation (MTT), respectively. Cytotoxicity analysis was determined by the resazurin method. The results were submitted to analysis of variance (ANOVA), followed by the student-Newman-Keuls test (p < 0.001). Results: After 24 hours, the RMGIC- 14%TMPnano group showed the lower RT value (p < 0.001); on the other side, the RMGIC- 14%TMPnano-0.25%Qui-Ph group showed the highest value after 7 days (p < 0.001). For RC, the Control group (24 hours) showed the highest value (p < 0.001); after 7 days the highest value was observed for the RMGIC-14%TMPnano-0.25%Qui-Ph group (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Qui-Ph, RMGIC- 14%TMPnano-0.5%Qui-Ph showed higher and similar release of F (p > 0.001). In the hardness test (KNH) the groups RMGIC-0.25%Qui-Ph; RMGIC-0.5%Qui-Ph; RMGIC- 14%TMPnano-0.5%Qui-Ph showed similar results (p < 0.001). The RMGIC- 14%TMPnano-0.25%Qui-Ph group showed the better effect on microbial growth (p < 0.001), as well as the highest efficacy on cell viability when compared to the other groups (p < 0.001). For the analysis of cytotoxicity at 24 hours, all groups were self-compatible and similar to the group with 100% metabolic activity (Control). After 72 hours of exposure to the cements, only the RMGIC-14%TMPnano-0.25%Qui-Ph group showed cell viability Gabriela Leal Peres Fernandes comparable to the control group. The other groups showed similar values (p > 0.001), which reduced cellular metabolic activity. Conclusion: According to the results obtained, it can be concluded that the incorporation of TMPnano-Qui-Ph to RMGIC has enhanced its properties and may be a clinical strategy in patients at high risk of caries and submitted to orthodontic treatment. (AU)

• FAPESP's process: 21/05532-7 - Evaluation of the physical-mechanical and microbiological properties of a new resin-modified glass ionomer cement containing nanoparticles of sodium trimetaphosphate and phosphoryl chitosan: in vitro study
• Grantee: Gabriela Leal Peres Fernandes
• Support Opportunities: Scholarships in Brazil - Master