Advanced Statistical Analyses to Reduce Inconsistency of Bond Strength Data

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Adhesion Science

Background:

• Microtensile bond strength (µTBS) is a critical measure for dental adhesive performance.
• Understanding factors influencing µTBS variability is essential for accurate material evaluation.
• Nondestructive testing methods offer potential for quantifying specimen characteristics influencing bond strength.

Purpose of the Study:

• To clarify the interrelationship of factors affecting microtensile bond strength (µTBS) values.
• To evaluate the influence of specimen characteristics on µTBS using nondestructive testing.
• To identify key parameters that correlate with and affect bond strength in dental restorations.

Main Methods:

• Prepared µTBS specimens from 10 human molars.
• Evaluated six factors: voids, resin/dentin X-ray absorption, dentin length, adhesion area, and tooth variability.
• Utilized optical coherence tomography and micro-computed tomography for nondestructive analysis.
• Analyzed µTBS data using general linear, linear mixed effects, and nonlinear regression models.

Main Results:

• Significant impact of individual tooth differences on µTBS (P < 0.001).
• Positive correlation between µTBS and dentin length (P < 0.001).
• Negative correlation between µTBS and adhesion area size (P = 0.001), with nonlinearity.
• Positive correlation between µTBS and dentin X-ray absorption coefficient (P = 0.022), with nonlinearity.
• Significant difference in µTBS based on the presence/absence of voids.

Conclusions:

• Tooth variability and specimen characteristics significantly influence dental adhesive bond strength.
• Dentin length and X-ray absorption coefficient correlate positively with µTBS.
• Adhesion area size negatively correlates with µTBS.
• Accurate adhesive performance evaluation requires consideration of tooth variability and methods to reduce bond strength variations.