| Abstract [eng] |
The dissertation aimed to examine wear and biocompatibility of commonly used dental luting cements. Main objectives of the study were: to examine the resistance to wear, to evaluate cytotoxicity of luting cements on primary human gingival fibroblasts (HGFs), and to identify pathways of cell death induced by extracts derived from different luting cements. The commonly used luting cements were tested: Hoffmann’s Zinc Phosphate (ZPC), GC Fuji Plus Resin Modified Glass Ionomer (RMGIC), and 3M ESPE RelyX Unicem Resin Cement (RC). A toothbrushing wear test was selected to examine wear; several in vitro methods (cell culture and culture extract testing) were used to test cytotoxicity. A considerable variation in wear resistance among different luting cements was observed. Zinc Phosphate cement were least resistant to wear, Resin Modified Glass Ionomer cement had a moderate level of wear, and Resin Cement had the best resistance to wear. All cements expressed cytotoxic effects, while the mechanisms for different cements varied. Hoffmann’s ZPC indicated less cytotoxicity than Fuji Plus RMGIC and RelyX Unicem RC. Pre-washing of luting cements reduced the cytotoxicity albeit not to the levels of the controls where there was no exposure to luting cements. The live cell imaging revealed that the apoptosis was the primary mechanism of a cell death induced by the RMGIC, whereas the RC and ZPC induced a cell death through a necrotic and caspase-independent pathway. The choice of an appropriate luting cement for final cementation of fixed prostheses needs careful consideration as an important factor for the successful treatment. |
