Aging and post-polymerization effects on conversion degree and properties of additive splint materials

Area of Science:

• Materials Science
• Biomaterials Engineering
• Dental Materials

Background:

• Additive manufacturing (AM) offers potential for custom dental splints.
• Evaluating AM splint materials' mechanical properties and aging resistance is crucial for clinical application.

Purpose of the Study:

• To analyze dimensional stability, flexural strength, hardness, wear, and conversion degree of AM splint materials.
• To investigate the impact of varied post-polymerization times and artificial aging on these properties.

Main Methods:

• Two AM systems (Dima Print Ortho, SprintRay Splint) and a control resin were tested.
• Materials underwent artificial aging (water/saliva, 28/84 days) and different post-polymerization cycles.
• Evaluated properties included dimensional change, flexural strength, hardness, wear, and conversion degree.

Main Results:

• No significant differences in dimensional change or flexural strength among materials.
• Doubling post-polymerization time improved Dima Print Ortho's strength and hardness but decreased SprintRay Splint's strength.
• Artificial aging negatively impacted hardness, except for Dima Print Ortho, which showed superior wear resistance.

Conclusions:

• Additive splint materials demonstrate comparable mechanical and dimensional performance to conventional resins.
• Optimizing post-polymerization cycles can enhance the properties of specific AM splint materials.
• Dima Print Ortho shows promising wear resistance and property enhancement with extended post-polymerization.