Evaluation of the radiopacity of single-shade composite restorative materials using a digital radiography system

Recently, single-shade universal composite resins have been introduced to the market to simplify restorative procedures. The inorganic structures of dental composites may influence several properties, including radiopacity. Radiopacity plays a crucial role in clinical dentistry as it enables the detection of recurrent caries, marginal defects, and restoration overhangs through radiographic examination. The aim of this investigation was to assess the mean gray value and compare the radiopacity of different single-shade composite resins using digital image analysis.

Seven single-shade universal composite resins (Omnichroma, Charisma Topaz One, Vitra Aps Unique, Admira Fusion x-tra universal, X-tra Fill, Essentia Universal and ZenChroma) and one multi-shade universal composite resin (Optishade) were used. The enamel-dentin segment, a typical aluminum (Al) step-wedge (1-10 mm), and the samples were placed on a phosphor imaging plate. For each image, the MGV and the standard deviation of the grey values for three different regions were calculated and the mean of these three values was recorded.

mmAI measurements of the study groups were found to be statistically significant different (p < 0.05). The differences were found between Charisma one and Voco xtrafil groups and between Enamel, Dentin and Zenchroma groups. Also, differences were observed between Dentin and Vittra aps unq groups. The radiopacity values of all materials tested were found to meet the requirements of ISO.

It is found that Glass particles containing composites have similar radiopacity as enamel due to their low atomic weight. Zirconium particles containing composites are more radiopaque than glass particles containing composites because of their higher atomic weight.