In vitro application of a nano-filled coating agent to improve the diametral tensile strength of glass ionomer cement

Abstract

During dental restoration, if the intraoral fluid comes into contact with the cement before it has hardened, the matrix-forming ions (Ca and Al) can be washed out, resulting in improper matrix formation and inferior mechanical properties. To prevent this, glass ionomer cement can be supplemented with a surface coating to protect it from water contamination in the early stages of setting and from moisture contamination and desiccation 10-30 min after insertion. This study aimed to investigate the influence of a nano-filled coating agent as a surface coating on the mechanical properties of glass ionomer cement, Fuji IX GP Extra. The glass ionomer cement specimens (6.00 mm in diameter and 3.0 mm in height) with and without the coating agent were stored in aqua bidest for 1 h, 1 day, and 1 week. Then, the diametral tensile strengths of the samples were measured and compared using an unpaired t-test. The coated glass ionomer cement exhibited significantly higher strengths than the uncoated samples after 1 h and 1 week, indicating that the nano-filled coating agent can be used in dental restoration to ensure mechanical strength of the cement.