Sealing Ability of Direct Adhesive Restorations in Posterior Teeth

Oral Session: Composites and AdhesionContraction stress at the bonding interfaces may occur as a result of polymerisation shrinkage of resin composite. This may affect the restorative seal. Observing the fluid flow within dentine can be used to assess the seal of a restoration. Objectives: The aim of this study was to investigate effects on the restoration-dentinal seal using different placement methods with various direct adhesive systems and restorative materials. Methods: Mesio-occluso-distal cavities were prepared on extracted third molars (n=42). Prepared teeth were divided into 6 groups and restored with either: Sonic activated bulk-fill resin composite, SonicFill™; Conventional nano-hybrid resin composite, Herculite® Ultra; Herculite® Ultra with a resin-modified glass-ionomer cement (RMGIC) base, Riva light-cure HV; Herculite® Ultra with a glass-ionomer cement (GIC) base, Riva self-cure HV; Conventional nano-hybrid resin composite, Filtek™ Supreme XTE with selective enamel etch-and-rinse adhesive, and; Filtek™ Supreme XTE with no separate etch-and-rinse step. Either a two-step self-etch bonding system, Optibond XTR and a one-step bonding system, Scotchbond Universal Adhesive was used. Using an automated flow-recording device, fluid flow was assessed before, during, and at periods after restoration, at 24-hours, 1-week, 1-month and 4-months. Fluid flow rates of the different restorative procedures, and post-restoration time intervals were analysed using ANOVA. The changes in flow rates between the different restorations were compared using Tukey’s test (p