effect of tea and coffee on color change of two types composite resins: nanofilled and micro hybrid

nasoohi n 1 hoorizad m1 torabzadeh tari n 2   1- assistant prof, department of operative dentistry, islamic azad university, dental branch, tehran,iran   2-dentist   corresponding author : nasoohi n: department, no 4, 10th neyestan ave, pasdaran, tehran   tel : 09125392175 email: [email protected]     background and aim: discoloration of dental composites is one of the major reasons of their change which can be influenced by internal and external factors. the aim of this study was to evaluate discoloration susceptibility of two nanofilled and micro hybrid composites by coffee and tea.   materials and methods: this experimental study was carried out on 30 composite specimens of point 4 and premise. the specimens were divided in 6 groups (n=5) .after primary color measurement by spectrophotometer the specimens were stored in distilled water ,coffee and tea for one week and then the color was measured . color changes (δe) were calculated. the data were analyzed by two –way anova,student t-test and post hoc tukey test.     results: the color change in both medius was significant for both composite groups. the effect of coffee and tea on discoloration of two composites was significant (p<0.05) .there was no significant difference between the color change of the two composites. also there was no significant   conclusion: color changes of two composites point 4 and premise by tea and coffee were clinically significant.   key words : nanofilled composite, micro hybrid composite, point4, premise discoloration, tea, coffee