Surface Roughness of Milled Lithium Disilicate With and Without Reinforcement After Finishing and Polishing: An In...

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Surface Characterization

Background:

• Computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics are widely used in restorative dentistry.
• Surface properties, such as roughness, are critical for the clinical performance and longevity of dental restorations.
• Understanding the influence of finishing and polishing techniques on CAD/CAM material surface is essential for optimizing clinical outcomes.

Purpose of the Study:

• To evaluate the efficacy of diverse finishing and polishing protocols on the surface roughness of three CAD/CAM ceramic materials.
• To compare the surface roughness of lithium disilicate (IPS e.max), lithium aluminosilicate-reinforced lithium disilicate (Straumann^® n!ce™), and nanofluorapatite glass ceramic (Ceram).

Main Methods:

• Fabrication of 2 mm thick flat specimens for each of the three CAD/CAM materials.
• Application of glazing (Ivoclar IPS e.max CAD crystall glaze spray or IPS e.max Ceram glaze paste) or polishing using three distinct systems (Brasseler Dialite HP, Ivoclar OptraFine, Komet LD/ZR).
• Measurement of surface roughness using a stylus profilometer and statistical analysis via two-way ANOVA.

Main Results:

• No significant difference in surface roughness (Ra) was observed among the different ceramic types.
• Finishing treatment groups and the interaction between finishing treatment and ceramic type showed statistically significant differences in Ra.
• Specific polishing systems demonstrated significant differences in Ra for Straumann^® n!ce™, with Brasseler Dialite HP and Komet LD/ZR showing comparable results.

Conclusions:

• The degree of surface roughness is dependent on the specific finishing system and ceramic material combination.
• Straumann^® n!ce™ exhibits more efficient polishing outcomes with Brasseler Dialite HP or Komet LD/ZR systems.
• Ivoclar crystal glaze spray demonstrated comparable effectiveness on Straumann^® n!ce™ and IPS e.max compared to IPS e.max Ceram glaze paste on IPS e.max Ceram.