Determining chewing efficiency using a solid test food and considering all phases of mastication.

Area of Science:

• Biomaterials Science
• Dental Mechanics
• Human Physiology

Background:

• Accurate measurement of food particle size reduction during chewing is crucial for understanding masticatory function.
• Traditional methods using Optosil® particles require a high number of chewing cycles (N≥15-20) due to initially unreliable median particle size (X₅₀) values.

Purpose of the Study:

• To enable reliable chewing ability testing at lower N-values by optimizing initial particle characteristics (size, shape, amount).
• To compare two key measures of chewing ability: chewing efficiency (N needed to halve initial particle size, N(1/2-X₀)) and chewing performance (X₅₀ at a specific N-value, X₅₀,N).

Main Methods:

• Eight subjects with natural dentition chewed four types of Optosil® particle samples, varying in number and size (8 cubes of 8mm, 9 half-cubes of 9.6mm, 4 half-cubes of 9.6mm, 2 half-cubes of 9.6mm).
• Particle size distribution was analyzed after a set number of chewing cycles (N).
• Log(X₅₀)-log(N) relationships were established using 2nd order polynomial curve-fitting to determine N(1/2-X₀) and X₅₀,N.

Main Results:

• Using mid-sized half-cubes of Optosil® yielded reliable X₅₀ values across all tested N-values.
• Employing 2 or 4 half-cubes significantly reduced the number of chewing cycles required to determine N(1/2-X₀) and X₅₀,N compared to traditional methods.
• The study demonstrated that optimized particle shapes and quantities enhance the efficiency of chewing ability assessments.

Conclusions:

• Reliable median particle size (X₅₀) measurements are achievable with fewer chewing cycles using appropriately sized and shaped Optosil® particles (mid-size half-cubes).
• Chewing efficiency (N(1/2-X₀)) is a more robust measure than chewing performance (X₅₀,N) for comparing inter-subject chewing ability.
• Optimized testing protocols allow for more efficient and reliable evaluation of masticatory function.