aps radiopacity presentation

Radiopacity  of  Nonmetallic  CAD/CAM  Restorative  Blocks Sherif Hosney BDS, Mohamed Kandil BDS,PHD, Omar el Mowafy BDS,PHD,FADM Introduction: An early study on the radiopacity of composite restorations was reported more than three decades ago.1 In the late 1980s, porcelain computer aided design/computer aided manufacture CAD/CAM blocks were developed and a study on their radiopacity was published.2 Current CAD/CAM technology has reached a stage of full development and has become widely used in dental offices and laboratories for fabrication of a wide range of indirect restorations.3 A considerable number od CAD/CAM blocks have been developed, the majority of which are based on porcelain and glass/ceramic formulations with few based on resin-­‐composite formulations. It is important to determine the radiopacity values of these new products. The ISO and ANSI/ADA published standardized procedures for quantifying the radiopacity of dental materilas.4,5 For a restorative material to be considered sufficiently radiopaque, its radiopacity values should be equal to or greater than that of dentin to allow for detection of recurrent decay. The aim of this Study was to determine the radiopacity of a group of CAD/CAM blocks used for fabrication of inlays, onlays and crowns using digital radiography. Materials and Methods: Specimens 2.0±0.05mm thick were cut from nine different blocks Table 1. Longitudinal section of the same thickness were obtained from molar and premolar teeth. Specimens were assigned to one of two groups, and each was placed on a digital radiographic sensor together with an aluminum step wedge. Following standardized technique , the sensor was exposed and two images were obtained from each group. Images were analyzed using ImageJ software to determine the number of pixels at five different locations for each specimen. Means and standard deviations were calculated and the data were statistically analyzed using one way ANOVA and Tukey test at a 95% level of significant. Radiopacity values were expressed as equivalent to aluminum thickness using calculated mean pixel and a generated path.

Results:ANOVA revealed a significant difference in mean pixels value among material (p