Dentin remineralization induced by experimental composites containing calcium orthophosphate particles

Author(s)

Campos, Amanda Lopes ; Chiari, Marina Damasceno Souza de Carvalho ; Vela, Beatriz Fonseca ; Trinca, Rafael Bergamo ; Balbinot, Gabriela de Souza ; Collares, Fabricio Mezzomo ; Braga, Roberto Ruggiero

• Document type: Journal article
• Source: Dental Materials; v. 41, n. 3, p. 7-pg., 2025-03-01.

Abstract

Objectives: This study aimed to verify if composites containing dicalcium phosphate dihydrate particles (DCPD) are able to induce dentin remineralization in vitro. Additionally, the mechanical properties of the materials were tested. Methods: Four composites with 50 vol% inorganic content and 1 BisGMA: 1 TEGDMA (mols) were prepared, with different DCPD:glass ratios (50:0, 40:10, 30:20 and 0:50). Ca2 + release in water was monitored for 8 weeks using inductively coupled plasma optical emission spectrometry (n = 3). Composites were applied to artificial lesions (180 mu m in depth) prepared in dentin discs and the specimens were kept in simulated body fluid for 8 weeks (n = 8-10). Dentin elastic modulus (EM) and hardness (H) across the lesion were determined by nanoindentation (5 mN, 5 s). Mineral density was determined by microCT. Composite degree of conversion (DC) was determined by near-FTIR spectroscopy (n = 3). Fracture strength and elastic modulus were determined using biaxial flexural test (n = 10). Data were analysed by ANOVA/Tukey test, except for mineral density (Kruskal-Wallis, alpha:0.05). Results: Ca2+ release increase linearly with DCPD fraction in the composite (p < 0.001). Lesions kept in contact with composites containing 40 % and 50 % DCPD presented significant increases in EM and H in the outer region (0-90 mu m) and in EM in the inner region (90-180 mu m) compared to the negative control. MicroCT was not able to differentiate among treatments. DCPD-containing composites presented DC higher than the control (p < 0.01). Flexural strength and modulus were inversely related to DCPD content (p < 0.001). Significance: The composite containing 40 vol% DCPD presented the best compromise between mechanical properties and remineralization potential. (AU)

• FAPESP's process: 20/13983-6 - Effect of temperature, pH and precursors concentrations on the synthesis of DCPD particles and its application on a remineralizing resin composite
• Grantee: Rafael Bergamo Trinca
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/04737-4 - Dentin remineralization with the use of composite containing calcium orthophosphate particles associated with a Polymer-Induced Liquid Precursor (PILP): material development, in vitro and randomized clinical studies
• Grantee: Roberto Ruggiero Braga
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 21/09657-9 - Dentin functional remineralization using an biomimetic analog, associated or not with a composite containing calcium orthophosphate
• Grantee: Amanda Lopes Campos
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)