Tooth Shape Controls Stiffness and Food Collection Efficiency in Biomimetic Radular Teeth

Area of Science:

• Biomimetics and Bioinspired Design
• Surface Engineering
• Tribology and Interfacial Mechanics

Background:

• Gastropod radular teeth are natural microscale cutting tools.
• Understanding geometry's role in their performance is crucial for designing artificial surfaces.
• Limited experimental data exists on shape-performance relationships for these structures.

Purpose of the Study:

• To investigate how specific geometric variations in biomimetic radular teeth affect interfacial mechanics and material removal.
• To establish quantitative shape-performance relationships for bioinspired abrasive interfaces.
• To identify key geometric parameters governing the efficiency of microscale cutting elements.

Main Methods:

• Stereolithography was used to print biomimetic tooth arrays based on *Spekia zonata* radula.
• Tooth stiffness was measured via bending tests.
• Interfacial performance was evaluated using a pull-through assay in agarose gels of varying stiffness.
• Force and removed mass were continuously recorded.

Main Results:

• Marginal tooth geometries exhibited higher stiffness and removed more substrate than central variants.
• Material removal did not proportionally increase with applied work in stiffer substrates, especially for central teeth.
• Performance was strongly correlated with active engagement, not solely work done.
• Geometry-limited contact regimes were identified.

Conclusions:

• Tooth geometry dictates stiffness and engagement, which are key parameters for efficient abrasive interfaces.
• Biomimetic design can leverage these geometric principles for advanced surface systems.
• Findings provide a foundation for optimizing bioinspired cutting and scraping tools.