Mechanical Properties of 3D-Printed Occlusal Splint Materials

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Additive Manufacturing

Background:

• Limited data exists on the mechanical properties of 3D printed materials for occlusal splints.
• Occlusal splints are crucial for managing bruxism and other dental conditions, requiring durable materials.

Purpose of the Study:

• To evaluate and compare the flexural strength and surface hardness of various 3D printed occlusal splint materials.
• To benchmark these properties against milled and conventional cold-polymerized materials.

Main Methods:

• 140 specimens of seven materials (five 3D printed, one milled, one cold-polymerized) were prepared per ISO 20795-1:2013.
• Flexural strength was assessed using a three-point flexure test, and surface hardness was measured using Vickers hardness testing.
• Statistical analysis included one-way ANOVA and Tukey's post-hoc test (α = 0.05).

Main Results:

• Flexural strength ranged from 46.1 ± 8.2 MPa to 106 ± 8.3 MPa.
• Vickers hardness values varied from 4.9 ± 0.5 VHN to 20.6 ± 1.3 VHN.
• Milled and cold-polymerized materials exhibited superior flexural strength and surface hardness compared to most 3D printed materials.

Conclusions:

• Significant differences exist in the mechanical properties of tested occlusal splint materials.
• Most 3D printed occlusal splint materials demonstrate lower flexural strength and surface hardness than milled or cold-polymerized alternatives.
• Further development is needed to enhance the mechanical performance of 3D printed materials for occlusal splint applications.