Effect of casein phosphopeptide-amorphous calcium phosphate on surface roughness of a silorane-based and methacrylate-based composite resin (In vitro comparative study)


Background: When using a fluoridated agent for caries-preventive intervention, the clinician should be careful not toallow the agent to come into contact with the composite restorations since topically applied fluorides were found toinduce adverse effects on the morphologic characteristics and composition of composite restorations. A newremineralizing agent "MI Paste" and its fluoridated form "MI Paste Plus" based on Recaldent technology (CPP-ACP)were developed. This study was conducted with the aim of assessing the effect of these new remineralizing agentson surface roughness of two types of composite resin materials.Materials and Method: Cylindrical specimens 12mm in diameter and 2mm in height were prepared from two types ofcomposite resin materials: Filtek™ P90 (a silorane-based composite material) and Filtek™ Z350 XT (a methacrylatebasednanofill composite material). Each specimen was cured against a celluloid strip in a specially designedcylindrical mold using a QTH light curing unit for 40 seconds. Forty specimens were prepared for each compositetype and subdivided into four subgroups of ten specimens each: Subgroup 1: without treatment, dry-stored in anincubator at 37ïC for one week (control subgroup), Subgroup 2: without treatment, stored in deionized water in anincubator at 37ïC for one week, Subgroup 3: treated with MI Paste once daily for one week, and Subgroup 4:treated with MI Paste Plus once daily for one week. Surface roughness of the specimens was obtained with a surfaceprofile testing machine, which used the roughness average (Ra) to assess surface changes. Several measurementswere taken for each specimen and the mean value of these measurements on one specimen was regarded as theRa of that specimen. The mean Ra value of each subgroup was then calculated.Results: The results of this study showed statistically non-significant differences among the different subgroups ofFiltek™ P90 composite resin material. Concerning Filtek™ Z350 XT composite resin material, the results showed astatistically highly significant difference in surface roughness between the subgroup stored in deionized water andthe control one, with statistically non-significant difference between the subgroups treated with MI Paste and MIPaste Plus and the control subgroup. Comparison of significance between the corresponding subgroups of bothcomposite types revealed statistically non-significant differences except for subgroup 2 which showed a statisticallysignificant higher surface roughness in Filtek™ Z350 XT than Filtek™ P90.Conclusions: The daily application of the MI Paste and MI Paste Plus for one week had non significant effect onsurface roughness of the silorane-based composite resin material Filtek™ P90. On the other hand, the application ofthese agents caused surface smoothening of the nanofilled methacrylate-based composite resin material Filtek™Z350 XT.