Bonding Ceramic to Dentin: Effect of Immediate Dentin Sealing

Statement of problem: Limited information is available on the effect of immediate dentin sealing (IDS) on bond strength.Purpose: This in vitro study investigated the effect of immediate dentin sealing and temporary cements on micro tensile bond strength (µTBS) to pressed ceramic restorations.Material and methods: A total of sixty human maxillary premolars were selected with comparable dimensions beside free of caries, fracture lines and cracks. Group of teeth after cutting the occlusal surface perpendicular to the long axis of the tooth to expose the mid-coronal dentin surface were followed by temporary cement either resin based (RC) (Provitemp) or conventional temporary cement (CC) (NETC) for two weeks. A total of 60 Emax press lithium disilicate glass ceramic specimens were fabricated. Sectioned teeth were divided to 6 groups according to dentin conditioning then bonded. Bonded specimens were stored in water bath at 37℃ for 5 months followed by thermal cycling for 5000 thermal cycles. µTBS was recorded for each specimen. Results: Immediate dentin sealing significantly increased the bond strength (P<.05) (µTBS) for the following groups compared to control group (C) (6.37±3.26); IDS (13.76±7.72), IDS-RC (15.24±5.6); IDS-CC) 13.99±6.98). However temporary cementation didn’t increase (µTBS) for groups; C-RC (5.08±2.91); C-CC(4.45±1.92).Conclusion: Immediate dentin sealing has a significant impact on long-term bonding to lithium disilicate glass ceramic compared to freshly cut dentin but temporization had a little effect. Clinical significance: Immediate dentin sealing improved adhesion and durability of lithium disilicate glass ceramics indirect restorations to human dentin.