Bond strength of silicon based soft liner cured in microwave to three types denture base materials

Aims: The purpose of this investigation is to assess the tensile bond strength (TBS) of three types of denture base materials fabricated by the conventional heat curing technique, three-dimensional printing (3D) and computer-aided design computer-aided manufacture (CAD-CAM) milling technology, bonded to microwave cured silicon base soft liner, and to evaluate the effect of surface treatment (acetone and laser) on the TBS. Materials and Methods: A total of 90 specimens, divided into three groups according to denture base type (Conventional, 3D and CAD-CAM), 30 specimens in each group, then subdivided into three subgroups according to the surface treatment (untreated, acetone and erbium, chromium-doped yttrium, scandium, gallium and garnet Er;Cr:YSGG laser), 10 specimens in each subgroup, the denture base materials were bonded to microwave cured silicone-based soft liner (DETAX Germany). TBS was tested by the universal testing machine. Mode of failure was tested by the stereomicroscope. The study results were statistically analyzed using SPSS program Version 26, using one-way ANOVA and Duncan’s test at P ≤ 0.05. Results: The CAD-CAM denture base showed a statistically significant increase in TBS value at p ≤ 0.05 (1.88±0.135), whereas the 3D type denture base showed a lower TBS (0.93±0.058), the surface treatment with Er;Cr:YSGG laser (1.699±0.13) followed by acetone (1.378±0.06) respectively, showed a highly significant increase in TBS value p ≤ 0.05. Conclusion: The CAD-CAM denture base demonstrated the highest TBS compared to the other types of denture base materials. The use of Er;Cr:YSGG laser and acetone respectively, improves TBS.