Mechanical properties and ion release from bioactive restorative composites containing glass fillers and calcium phosphate nano-structured particles

Author(s)

Chiari, Marina D. S. ^[1] ; Rodrigues, Marcela C. ^[1] ; Xavier, Tathy A. ^[1] ; de Souza, Eugen M. N. ^[1] ; Arana-Chavez, Victor E. ^[1] ; Braga, Roberto R. ^[1]

Affiliation

^[1] Univ Sao Paulo, Sch Dent, Dept Biomat & Oral Biol, BR-05508000 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Dental Materials; v. 31, n. 6, p. 726-733, JUN 2015.
• Web of Science Citations: 22

Abstract

Objective. To evaluate the effect of the replacement of barium glass by dicalcium phosphate dihydrate (DCPD) particles on the mechanical properties and degree of conversion (DC) of composites. Additionally, calcium and hydrogen phosphate (HPO42-) release were followed for 28 days. Methods. Nine composites containing equal parts (in mols) of BisGMA and TEGDMA and 40, 50 or 60 vol% of total filler were manipulated. Filler phase was constituted by silanated barium glass and 0%, 10% or 20% of DCPD particles. DC was determined by near-FTIR. Biaxial flexural strength (BFS) and modulus (E) were tested using the ``piston on three balls{''} method, while fracture toughness (KO used the ``single edge notched beam{''} method. Specimens were tested after 24 h and 28 days in water. Ion release was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). Data were analyzed by ANOVA/Tukey (DC and ion release) or Kruskal-Wallis/Mann-Whitney (mechanical properties; alpha: 5%). Results. DC was not affected by DCPD. The presence of DCPD reduced BFS for both storage times, while differences in E became evident after 28 days. After 24h, K-Ic increased with the addition of DCPD; after 28 days, however, K-Ic decreased only for DCPD-containing composites. Calcium release was similar for both DCPD contents and remained fairly constant during the 28-day period. Overall, HPO42- release was higher at 7 days and did not decrease after 14 days. Signcance. The composite with the highest filler level and 10% DCPD represented the best compromise between mechanical properties after aging in water and ion release. (C) 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 12/25253-6 - Effect of the addition of amorphous calcium phosphate (ACP) over the physicochemical properties of experimental composites
• Grantee: Marina Damasceno e Souza de Carvalho Chiari
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/04532-4 - Bioactive composites: effect of different calcium phosphate compounds and organic matrix composition on the remineralizing potential and physicochemical properties of experimental materials
• Grantee: Roberto Ruggiero Braga
• Support Opportunities: Regular Research Grants