RÉSUMÉ
BACKGROUND:The glass ionomer cement has good biological stability and can sustain the release of fluoride, which has been used as dental repair materials. But because of its low mechanical strength, the glass ionomer cement is confined to the front teeth and other parts with smal er force. OBJECTIVE:To analyze the compressive strength, microleakage and other physical performances of Fuji IX glass ionomer cement after the addition of 8%modified nano-hydroxyapatite. METHODS:(1) Universal testing machine was applied to detect the compressive strength of Fuji IX glass ionomer cement, Fuji IX glass ionomer cement added with 8%modified nano-hydroxyapatite, and super glass ionomer to fil the stainless steel cylinder. (2) Fuji IX glass ionomer cement, Fuji IX glass ionomer cement with 8%modified nano-hydroxyapatite and super glass ionomer were used to fil the tooth cavity;then, the microleakage was detected. (3) Fuji IX glass ionomer cement, Fuji IX glass ionomer cement added with 8%modified nano-hydroxyapatite, and super glass ionomer were used to fil stainless steel rectangular specimens. Then, universal material testing machine was applied to detect the bending strength value. RESULTS AND CONCLUSION:The compressive strength, microleakage, and bending strength of specimens fil ed with Fuji IX glass ionomer cement the addition of 8%modified nano-hydroxyapatite were better than the other two groups, and Fuji IX glass ionomer cement was superior to the super glass ionomer in the compressive strength, microleakage and bending strength of fil ed specimens. It is shown that Fuji IX glass ionomer cement after addition of 8%improved nano-hydroxyapatite can improve the compressive strength and microleakage.