Correlation of three wear testing methods and surface roughness analysis in 3D-printed crown materials

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Tribology

Background:

• Additive manufacturing offers novel dental restorative materials.
• Understanding wear resistance is crucial for long-term clinical success.
• Standardized wear testing protocols are needed for material comparison.

Purpose of the Study:

• To evaluate and correlate the wear resistance of three additively manufactured dental restorative materials.
• To compare three distinct wear testing methods: ball-on-disc, block-on-ring, and linear reciprocation.
• To assess the influence of load and material type on wear outcomes.

Main Methods:

• In vitro wear testing of three polished/glazed restorative materials under 49 N and 70 N loads in artificial saliva.
• Utilized ball-on-disc, block-on-ring, and linear reciprocation wear tests.
• Measured vertical loss, step-height, surface roughness, and friction coefficient; statistical analyses performed.

Main Results:

• Weak positive correlations observed between ball-on-disc and reciprocation methods; weak to negative correlations between reciprocation and block-on-ring.
• Material type significantly affected vertical loss (P < 0.03).
• Reciprocation increased surface roughness for specific materials (P < 0.05); increased load minimally impacted wear but variably affected roughness.

Conclusions:

• Wear performance of additively manufactured dental materials varies significantly depending on the testing method employed.
• Correlations between different wear tests were generally weak, highlighting the need for method-specific interpretation.
• Friction coefficients remained clinically acceptable, but surface roughness was influenced by testing conditions and material type.