Enamel-like Polymer-Infiltrated Ceramic Materials for Dental Applications

Area of Science:

• Biomaterials Science
• Dental Materials Science
• Nanotechnology

Background:

• Polymer-infiltrated ceramic network (PICN) composites mimic natural tooth enamel's mechanical properties.
• Current PICN materials have limited fracture toughness, hindering their use in dental restorations.
• Natural enamel's rod-sheath architecture inspires strategies to enhance PICN fracture toughness.

Purpose of the Study:

• To develop bionic PICN composites with an enamel-like structure to improve fracture toughness for dental applications.
• To investigate the effect of simulated enamel rod structures on the mechanical and tribological properties of PICN composites.
• To evaluate the adhesive properties and cell compatibility of the novel bionic PICN materials.

Main Methods:

• Three types of zirconia ceramic scaffolds with varying enamel-like rod structures (straight, gnarled, natural distribution) were fabricated using digital light processing.
• Scaffolds underwent surface treatment and resin infiltration to create rod-sheath structures in the PICN material.
• Characterization included microstructure analysis, flexural strength, fracture toughness, modulus, wear, adhesion, and cytotoxicity testing, with VITA Enamic as a control.

Main Results:

• The PICN composite with a natural rod distribution structure demonstrated the highest flexural strength and fracture toughness.
• This bionic PICN exhibited a fracture toughness of 7.0 ± 0.6 MPa·m^1/2, approximately seven times that of VITA Enamic.
• Superior wear resistance compared to VITA Enamic and bovine enamel was observed, with comparable bond strength to bovine dentin after surface treatment.

Conclusions:

• The developed bionic PICN composites, inspired by natural enamel, significantly enhance fracture toughness and wear resistance.
• The natural rod distribution structure is most effective in improving mechanical properties.
• These novel materials show great promise for advanced dental restorations and prosthetic applications due to their improved performance and biocompatibility.