[Color differences between light-cured composite resin made shade guides and manufactured shade guides]

Area of Science:

• Dental Materials Science
• Colorimetry
• Restorative Dentistry

Background:

• Accurate shade matching is crucial for aesthetic dental restorations.
• Discrepancies between shade guides and composite resins can lead to suboptimal aesthetic outcomes.
• Understanding color differences is essential for material selection and clinical application.

Purpose of the Study:

• To investigate and quantify color differences between dental shade guides and light-cured composite resins.
• To compare the color accuracy of Silux Plus and Silux composite resins against their respective shade guides.
• To analyze color variations across different regions (incisal, central, cervical) of the specimens.

Main Methods:

• Resin specimens were fabricated using Silux Plus and Silux composite resins in a shade-guide metal mold, ensuring identical shape and size.
• Color measurements were performed using a Murakami Color Research Laboratory Fast Spectrophotometer CMS-500 and Flexible Sensor FS-1.
• Color differences (delta E*ab) were assessed by comparing resin specimens with their corresponding shade guides at incisal, central, and cervical areas.

Main Results:

• All shade guide and resin specimen pairs exhibited color differences detectable by the human eye (delta E*ab values).
• Greater color discrepancies were observed for incisal and deep/dark shades compared to general shades.
• Shade guides showed a wider range of L* values than resin specimens, often with lower L* values.
• a* values for shade guides were generally lower in magnitude than for resin specimens, with all showing negative values.
• b* values varied, with shade guides exhibiting higher or lower values than resin specimens depending on the specific color.

Conclusions:

• Clinically significant color differences exist between shade guides and light-cured composite resins, impacting shade reproduction.
• Incisal and dark shades present greater challenges for accurate shade matching due to larger color differences.
• Material manufacturers and dental professionals should be aware of these color variations to improve shade selection and achieve better aesthetic results.