Comportamento físico-químico e densidade radiográfica de cimentos endodônticos biocerâmicos contemporâneos após imersão em água

Abstract

The aim of this study was to evaluate the physicochemical properties of different bioceramic cements applied in endodontics. This in vitro observational study included MTA Repair HP, MTA Angelus®, Bio-C® Repair, MTA Fillapex, Bio-C® Sealer, Biodentine™, CIMMO HD, CIMMO HP, and CIMMO DTA. Ten standardized specimens (4 mm × 1 mm) were prepared for each material using a Teflon split matrix, compressed to avoid bubbles, and with thickness checked. One specimen of each material was subjected to thermal analysis, while the remaining nine were randomly assigned to three immersion periods in deionized water (24 h, 7 days, and 30 days; n = 3). Radiopacity was evaluated using a semi-direct digital system with photostimulable phosphor (PSP) plates and compared with human enamel, dentin, and an aluminum scale. Solubility was determined as relative mass variation, while pH and electrical conductivity were measured in the storage solution at each time point. Thermal behavior was analyzed using simultaneous thermogravimetric and differential thermal analysis (TG/DTA). Radiopacity remained stable during immersion periods, with MTA Angelus® and Bio-C® Sealer showing the highest values, while CIMMO HD and Biodentine™ remained below 3 mm Al. All cements induced an alkaline environment, with Biodentine™ and MTA Angelus® reaching maximum pH at 30 days (12.31 and 11.59, respectively) and Bio-C® Sealer peaking at 7 days (11.53) before decreasing. Electrical conductivity increased over time for most materials, with Biodentine™ showing the highest values (1451.60 µS/cm at 30 days). The materials MTA Fillapex®, MTA Repair HP, Bio-C® Repair, and Bio-C® Sealer lost mass in 7 days, stabilizing in 30 days; Biodentine™ showed a reduction in 30 days. Thermal analysis revealed that MTA Repair HP and Bio-C® Repair were the most thermally stable (residual mass of 89.46% and 87.07%), while MTA Fillapex® and Bio-C® Sealer decomposed more extensively (56.37% and 67.70%). It is concluded that the tested bioceramic endodontic cements presented distinct physicochemical behaviors that can directly influence their clinical performance. Radiopacity, solubility, pH, ionic release, and thermal stability varied among the materials, highlighting that no single cement stands out in all properties.These findings highlight the need for an individualized evaluation in the selection of bioceramic cements for specific endodontic applications.