Influence of the zirconia cleaning method on prosthesis adhesion after saliva contamination

Abstract Introduction An important clinical factor related to the adhesion of ceramic restorations is the contamination with saliva before cementation. The zirconia has strong affinity with the ions present in the saliva which can interfere in the cementation adhesion. Objective to evaluate the influence of the zirconia cleaning methods on the dentin adhesion system after contamination with saliva. Material and method Eight zirconia samples (4x11x3 mm) were cut from pre-sintered (3Y-TZP, In-Ceram-VITA®) zirconia blocks, sintered and sandblasted with alumina particles. After sintering the samples were washed in distilled water on the ultrasound and randomly divided into two groups based on the type of adhesion cement RelyX U200 Clicker® (group R) or Multilink N® (group M). Before cementation the samples were divided into four subgroups (n = 10) according to the cleaning and cementation methods: RG1 and MGI (without contamination with saliva); RG2 and MG2 (without contamination and cleaning with Ivoclean®); RG3 and MG3 (with contamination and cleaning with H2O); RG4 and MG4 (with contamination and cleaning with Ivoclean®). After cementation, the samples were stored in water (37 °C for 10 days). The adhesion strength was determined by the shear strength test. Result The results showed that the highest and lowest resistance were from the RG2 and MG2 subgroups, respectively. Among the samples cemented with RelyX® only the RG4 subgroup presented a difference in adhesion resistance (p = 0.018) in relation to the other subgroups. Among the subgroups cemented with Multilink N®, there was no statistical difference (p> 0.05) in shear strength. Conclusion Based on the results it was possible to conclude that the commercial cleaning agent Ivoclean® was not effective in the decontamination and did not influence the shear strength.