UBC Theses and Dissertations
Comparison of adherence of self-cured adhesive resin cement to lithium disilicate ceramics and ceramic resin composites using fracture mechanics Mesmar, Samer
Objective : The goal of this study was to apply fracture mechanics methodology to assess the effect of surface preconditioning on the short and long term adherence between a widely used adhesive resin cement (RelyX Ultimate, 3M ESPE) and recently introduced CAD/CAM materials : two ceramic resin composites (Lava Ultimate – 3M ESPE and Enamic – Vita-Zahnfabrik) and a ceramic (IPS e.max – Ivoclar-Vivadent). Materials and Methods : Sixty specimens were prepared from each e.max and Enamic, and 120 specimens were prepared for Lava Ultimate. Ceramic resin composite blocks samples were prepared by wet cutting and grinding. Ceramic samples were prepared using the lost wax procedure and pressing. Enamic and e.max bonding surfaces were treated with hydrofluoric acid. Lava Ultimate received two surface treatments : sandblasting and Rocatec soft. All samples were bonded using an adhesive and resin cement and stored in water at 37°C. After 24h storage, half of the specimens from each group were tested to determine the interfacial KIC using an Instron universal testing machine; the remaining specimens were tested after 60d storage. Scanning electron microscopy fractographic analysis was performed on representative fractured samples from each group to determine the mode of failure. To determine the adhesive resin cement KIC, twenty specimens were prepared using a mold. Half of the specimens were tested after 24h storage in water at 37°C and the other half were tested after 60d storage. The KIC results were analyzed using two-way ANOVA followed by Scheffé multiple means comparisons. Results : Lava Ultimate had a significantly higher interfacial KIC at 24h when compared to Enamic and e.max. For Lava Ultimate, crack propagation occurred cohesively through the adhesive resin cement. In Enamic and e.max samples, crack propagation occurred cohesively within the adhesive layer. Only Enamic showed a significantly higher interfacial KIC at 60d, compared to the other groups. Lava Ultimate and e.max interfacial KIC, and cement KIC showed lower values at 60d. Conclusion : For Lava Ultimate, surface silicatisation seems to be a more effective surface treatment compared to only sandblasting. For Enamic and e.max, the application of silane coupling agent and adhesive contained in one solution does not seem to be effective.
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Attribution-NonCommercial-NoDerivs 2.5 Canada