Avaliação das propriedades antimicrobianas, mecânicas e adesivas de cimentos de ionômeros de vidro empregados no tratamento restaurador atraumático

Abstract

This study evaluated in vitro the antimicrobial, mechanical and adhesive properties of glass ionomer cements used in the Atraumatic Restoration Treatment. The glass ionomer cements (GIC) Ketac-Molar, Ion-Z, Vitro-Molar and Fuji-IX were evaluated in agar diffusion test (AD), bacterial adhesion (BA), abrasion (Ab), erosion (Er), water sorption and solubility (WS-SB), hygroscopic expansion (HE), flexural strength (FS), microleakage (ML), and micro-shear (MS). For AD 4 wells were filled with the GICs in petri dishes with S. mutans. The zone of inhibition was measured. For BA five specimens of each GIC were inoculated into BHI broth with S. mutans. Then the specimens were washed with PBS and after, the PBS were diluted twice to then seeded into petri dishes and the UFC/ml was counted. For Ab, 40 specimens were submitted to simulated brush cycles, evaluating mass, roughness and hardness. For Er 80 specimens were analyzed by roughness, mass and microhardness, according to the erosive cycle with acidic beverages. For WS-SB 40 specimens were evaluated according to mass for 56 days. For HE, 40 glass cylinders were filled with GICs and evaluated for 4 weeks. For FS each CIV was tested in the three-point bending test. For ML, 80 teeth were restored and submitted to thermocycling for evaluation of microleakage. For MS 80 teeth were sectioned and placed in PVC tubes. The specimens were restored with cylinders made of the GIC and evaluated in a universal testing machine. Data were analyzed using the Tukey test (p ≥ 0.05). In AD results, Ion-Z showed the highest antimicrobial activity in each evaluated time. In AB, Fuji-IX presented the highest bacterial adhesion. In Ab the GICs did not present significant difference after brushing in mass and microhardness; in roughness, Ion-Z was affected. In Er, the GICs were not affected by the acidic beverages in mass, however, the results of microhardness and roughness have changes. In SO-SB, Ion-Z had the highest values. In HE, Vitro-Molar and Ion-Z presented hydroscopic expansion. In RF, Fuji-IX had the highest value, without significant difference with Ketac-Molar and Ion- Z. In IM, Fuji-IX had less infiltration in permanent and in deciduous teeth; the others GICs didn´t have significant differences. In MS, Ketac-Molar, Ion-Z and Fuji-IX presented the best values without significant differences; the adhesive fractures were the ones with highest percentage. The study concluded that Ketac-Molar, Fuji-IX and Ion-Z presented similar results. Ion-Z is another option for ART restorations, however, in vivo studies should be performed. Keywords: glass ionomer cements, atraumatic restorative treatment, antimicrobial properties, mechanical properties, adhesive properties