Odontologia

Abstrato

Improvement of the Adhesive Strength between Silicone-Based Soft Liner and Thermocycled Denture Base with Plasma Treatment

Xiaoqing M,Chunyuan Qiao,Xin Zhang,Yingying Chen,Huaiqin Zhang*

Purpose: The aim of this study was to investigate the effect of oxygen plasma treatment on the tensile bond strength of a silicone-based soft liner to a thermocycled denture base.

Methods: 2 10×10×1 mm heat-polymerized acrylic resin blocks for X-ray photoelectron spectroscopy (XPS) analysis were prepared (one served as control, and another treated by oxygen plasma for 4 min). 30 (10×10×1 mm) acrylic resin blocks for contact angle measurement and 80 (8×10×30 mm) for tensile test were also prepared and equally divided into five groups: a control group and four experimental groups (exposure to oxygen plasma for 1min, 2 min, 3 min and 4 min, respectively). All blocks were thermocycled (5-55°C, 5000 cycles) before oxygen plasma treatment. After oxygen plasma treatment, the soft liner was processed between two blocks according to manufacturer’s instructions and polymerized. All specimens were submitted to a tensile test using a universal testing machine and results were statistically analyzed (ANOVA, p<0.05, Tukey’s HSD test).

Results: The XPS analysis showed that the O/C ratio increased from 0.324 for the control group to 0.498 for the 4-min exposure group. With regard to water contact angle, the lowest value was obtained from the 4-min exposure group (37.32°). For the tensile test, the highest tensile bond strength was observed in the 4-min exposure group (1.998 ± 0.110 MPa) and the lowest was in the control group (0.831 ± 0.059 MPa).

Conclusions: Oxygen plasma treatment was efficient in improving the tensile bond strength between siliconebased soft denture liner and thermocycled denture base.