J Korean Acad Prosthodont.  2025 Jul;63(3):218-226. 10.4047/jkap.2025.63.3.218.

Comparison of shear bond strength between chairside relining material and denture base resins fabricated by CAD-CAM and heat-curing methods

• Jung GY
• Lee SK
• Lee JI
• Lee JH

• KMID: 2570664
• DOI: http://doi.org/10.4047/jkap.2025.63.3.218

Abstract

Purpose
This study was aimed to assess the shear bond strength between chairside relining material and denture base resins made by CAD-CAM and heat-curing methods.
Materials and methods
The specimens of denture base resins were divided into 4 groups based on their fabrication methods. Specimens were fabricated by additive manufacturing (A), subtractive manufacturing (S), heat-curing process (H) and chairside relining material auto-polymerization (C). The chairside relining material was injected into the same position on the surface of all denture base resin specimens using a silicone mold and polymerized. Shear bond strength was measured by a universal testing machine. Scanning electron microscope (SEM) analysis was conducted to classify the failure patterns as adhesive, cohesive, or mixed failures. Statistical analyses between groups were conducted by one-way ANOVA and Tukey’s tests (α = .05).
Results
Statistically significant differences were observed between group A and both group H and S in the shear bond strength (P < .05). No significant difference was found between the group H and S (P > .05). Regarding fracture patterns, group H and S exhibited the highest frequency of mixed failures, while group A showed a predominance of adhesive failures, with no cohesive failures observed.
Conclusion
Shear bond strength between the denture base resins and chairside reline material was highest in the heat-curing method. For the CAD-CAM methods, it was higher in the subtractive manufacturing method than the additive manufacturing method.

Keyword

3D printing; Denture relining; Milling; Shear strength