Ion release mechanisms in composites containing CaP particles and hydrophilic monomers

Autor(es)

Trinca, Rafael Bergamo ; Vela, Beatriz Fonseca ; Vilela, Handially dos Santos ; Braga, Roberto Ruggiero

• Tipo de documento: Artigo Científico
• Fonte: Dental Materials; v. 40, n. 7, p. 9-pg., 2024-06-14.

Resumo

Objective To investigate the effect of hydrophilic/permeable polymer matrices on water sorption/solubility (WS/SL), Ca2+ release, mechanical properties and hydrolytic degradation of composites containing dicalcium phosphate dihydrate (DCPD) particles. Methods Six composites were tested, all with 10 vol% of glass particles and either 30 vol% or 40 vol% DCPD. Composites containing 1BisGMA:1TEGDMA in mols (at both inorganic levels) were considered controls. Four materials were formulated where 0.25 or 0.5 of the BisGMA/TEGDMA was replaced by pyromellitic dianhydride glycerol dimethacrylate (PMGDM)/ polyethylene glycol dimethacrylate (PEGDMA). Composites were tested for degree of conversion (FTIR spectroscopy), WS/SL (ISO 4049) and Ca2+ release (inductively coupled plasma optical emission spectroscopy). Fracture toughness (FT) and biaxial flexural strength/modulus (BFS/FM) were determined after 24 h and 60 days in water. The contributions of diffusional and relaxational mechanisms to Ca2+ release kinetics were analyzed using the semi-empirical Salim-Peppas model. Data were analysed by ANOVA/Tukey test (alpha: 0.05). Results WS/SL was higher for composites containing PMGDM/PEGDMA compared to the controls (p < 0.001). Only at 40% DCPD the 0.5 PMGDM/PEGDMA composite showed statistically higher Ca2+ release than the control. Relaxation diffusion was the main release mechanism. Initial FT was not negatively affected by matrix composition. BFS (both DCPD fractions) and FM (30% DCPD) were lower for composites with hydrophilic/permeable networks (p < 0.01). After 60 days in water, composites with PMGDM/PEGDMA presented significant reductions in FT, while all composites had reductions in BFS/FM. Significance Increasing matrix hydrophilicity/permeability significantly increased Ca2+ release only at a high DCPD fraction. (AU)

• Processo FAPESP: 19/04737-4 - Remineralização dentinária com o uso de um compósito contendo partículas de ortofosfato de cálcio associado a um precursor mineral em fase líquida (Polymer-Induced Liquid-Precursor, PILP): desenvolvimento de material, estudos in vitro e clínico aleatorizado
• Beneficiário: Roberto Ruggiero Braga
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 21/09297-2 - Efeito da proporção entre partículas de DCPD e vidro de bário sobre a tenacidade à fratura (KIc) de compósitos experimentais
• Beneficiário: Beatriz Fonseca Vela
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 20/13983-6 - Efeito da temperatura, pH e concentração de precursores na síntese de partículas de DCPD e sua aplicação em um compósito resinoso remineralizante
• Beneficiário: Rafael Bergamo Trinca
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado