Adhesion of auto-mixed and manual-mixed self-adhesive resin cements to dentin on exposure to long-term high-altitude pressure

Purpose The purpose of this study is to test the shear-bond-strengths of auto-mixed and manual-mixed self-adhesive resin cement to dentin on long-term high-altitude pressure. Design/methodology/approach Human molars were embedded in acrylic resin. Sixty composite resin discs were obtained. The composite resin discs were bonded to dentin using hand-mixed and auto-mixed self-adhesive resin cement. After cementation, the samples were stored in artificial saliva and divided into two subgroups (n = 30), hypobaric pressure and the atmospheric pressure group. The specimen underwent three pressure cycles per day for 100 days. The failure types were evaluated after debonding with scanning electron microscopy. The shear bond strength was tested with Universal Testing Machine. Analysis of variances/Tukey post hoc tests were used for statistical analysis. Groups were also evaluated by the Weibull modulus. Findings Regardless of hypobaric pressure changes, the highest bond strength was examined in auto-mixed Panavia SA samples. A significant difference was found in both auto-mixed MaxCem EC and hand-mixed RelyX U200 group after exposure to hypobaric pressure compared to the control group. Originality/value The luting cement-type, mixing methods of cements and environmental pressure changes significantly influence the bond strengths. Dentists can use auto-mixed self-adhesive resins in patients likely to be exposed to hypobaric pressure.