Biocompatibility and bioactivity of tricalcium silicate- based cements: in vitro and in vivo studies

Author(s)

Aline Silva Andrade

• Document type: Master's Dissertation
• Press: Araraquara. 2016-05-31.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araraquara
• Defense date: 2016-03-31
• Advisor: Mario Tanomaru Filho; Paulo Sérgio Cerri

Abstract

Tricalcium silicate- based cements have been developed as an alternative to Mineral Trióxido Agregado (MTA). The aim of the study was to evaluate biocompatibility and bioactivity of the tricalcium silicate cement replaced with 20% zirconium oxide (STC) e MTA Plus (MTAP). Chaper 1- Human osteoblastic cells (Saos-2) were exposed to test materials and assessed for viability, MTT and Neutral Red (NR) assay, and bioactivity for ALP activity assay and alizarin red staining (ARS). Unexposed cells acted as the control group. Statistical analysis was performed using ANOVA and the Bonferroni post- test (P < 0.05) to MTT, NR and ALP, and ANOVA and Tukey post- test (P ≤ 0.05) to ARS. MTT and NR results, all tested cements were non-cytotoxic. The highest ALP activity occurred at the 7th days. Mineralized area was observed in all materials, STC group showed lower mineralized area. Experimental tricalcium silicate with 20% zirconium oxide and MTA Plus have present biocompatibility and bioactive potential. Chapter 2- The inflammatory reaction induced by tricalcium silicate cement replaced with 20% zirconium oxide (STC) e MTA Plus (MTAP) was evaluated in rat subcutaneous tissues. A polyethylene tube filled with STC (n= 20) and MTAP (n= 20) was placed into the dorsal subcutaneous of forty rats; in the control group (GC; n= 20), empty tubes were implanted. After 7, 15, 30 and 60 days, the polyethylene tubes surrounded by connective tissue were embedded in paraffin. The number of inflammatory cells was estimated in HE-stained sections; numerical density of interleukin-6 (IL-6)- immunolabelled cells was also performed. The differences amongst the groups were analysed statistically by Tukey’s test (P ≤ 0.05). A high number of inflammatory cells and IL-6-positive cells were observed at 7 days, in all groups; however, the number of inflammatory was significantly higher (P ≤ 0.05) to STC and MTAP groups. The number of IL-6- positive cells in the capsules was not significantly different amongst GSTC, GMTAP and GC groups in each period. In the capsules of animals from all groups, a gradual and significant reduction (P ≤ 0.05) of these parameters was seen over time. At 60 days, the connective tissue capsules exhibited numerous fibroblasts and bundles of collagen fibres. Experimental tricalcium silicate with 20% zirconium oxide and MTA Plus are biocompatible. (AU)

• FAPESP's process: 14/13353-1 - Biocompatibility and mineralization capacity of tricalcium silicate-based cements: in vitro and in vivo study
• Grantee: Aline Silva Andrade
• Support Opportunities: Scholarships in Brazil - Master