Marginal adaption of two esthetic complete crowns

Area of Science:

• Dental materials science
• Prosthodontics
• Biomaterials engineering

Background:

• Accurate crown fit is crucial for long-term dental restoration success.
• Evaluating the marginal fit of different crown types is essential for clinical application.
• Previous studies have shown variability in the fit of various dental crown materials.

Purpose of the Study:

• To compare the marginal fit of porcelain-fused-to-metal (PFM) crowns and Dicor crowns.
• To assess the fit of PFM crowns before and after porcelain application using the porcelain-margin technique.
• To establish which crown type offers superior fit in an in-vitro setting.

Main Methods:

• Fabrication of twenty artificial crowns for in-vitro testing.
• Utilized a hardened stainless steel five-piece die assembly for uniform wax patterns and measurements.
• Compared the fit of ten PFM crowns (pre- and post-porcelain application) with ten Dicor crowns.

Main Results:

• Metal substructures of PFM crowns exhibited the best fit prior to porcelain application.
• PFM crowns demonstrated an oversized fit after porcelain application.
• Dicor crowns consistently presented an undersized fit compared to the die assembly.

Conclusions:

• The marginal fit of PFM crowns can be compromised by the porcelain application process.
• Dicor crowns may present fit challenges due to their undersized nature.
• Pre-porcelain metal substructures offer superior marginal accuracy in this in-vitro comparison.