Evaluation of adhesive properties of three resilient denture liners by the modified peel test method

The characteristics of adhesive properties between a denture base and resilient denture liner were investigated by a modified peel test with an L-shaped metal attachment. Three commercially resilient denture lining materials, namely GC Reline Soft (S), GC Reline Extra Soft (ES), and GC Reline Ultra Soft (US), were evaluated. Acrylic resin (GC Acron) was used as denture base material. Peel specimens consisting of the denture base acrylic resin and resilient denture liner were tested after storage for 1 and 30 days in distilled water at 37 °C. The modified peel test method gave load–displacement curves and work of adhesion (WA) values of the denture base material and resilient denture liner. The WA of specimens after 1 day of storage ranged from 1.71 to 2.55 N mm−1 and increased in the order from US to S to ES. On the other hand, the WA of specimens after 30 day of storage ranged from 1.44 to 2.47 N mm−1 and increased in the order from US to ES to S. US had significantly lower WA after 1 and 30 days of storage than did S and ES (P < 0.05). Comparison of the WA between 1 and 30 days, reveals large differences for ES and US, but not for S. This could be explained by the difference in failure modes. Within the limitations of this investigation, it was concluded the modified peel test is effective for evaluating the adhesion between denture base material and a resilient denture liner.