"opacity and color changes of light-cured ideal makoo (idm) "

statement of problem: esthetic materials undergo some physical and mechanical changes, during their service in oral cavity. purpose: the aim of this study was the evaluation of the color and opacity stability of ideal makoo (idm) composites and compare it with tetric ceram. material and methods: fifteen disk shaped samples of each material was divided into three groups of five. different aging treatments were applied to each group. the contrast ratio of 1mm thickness and e of the samples were evaluated at base line and after aging, using cie system and data flash spectrophotometer. all the samples were kept at 37c. results: baseline opacity of idm was relatively high (77.60%8.6). both materials showed increased opacity after aging. the highest e belonged to idm samples of b group, which was significantly more than tetric ceram (p<0.05). tetric ceram, also showed some degree of color change (e=4.60 and 5.79, on black and white background, respectively), which is noticeable clinically. conclusion: the research showed that idm can not be a reliable esthetic material, unless some improvements in the chemical composition will be achieved.