Effect of time on tensile bond strength of resin cement bonded to dentine and low-viscosity composite

Duarte, Rosângela Marques; de Goes, Mario Fernando; Montes, Marcos Antonio Japiassú Resende

doi:10.1016/j.jdent.2005.03.002

« Previous Next »Journal of Dentistry
Volume 34, Issue 1 , Pages 52-61, January 2006

Effect of time on tensile bond strength of resin cement bonded to dentine and low-viscosity composite

Received 2 December 2004; received in revised form 3 March 2005; accepted 13 March 2005.

Summary

Objectives

The purpose of this study was to evaluate the tensile bond strength (TBS) of Panavia F resin cement (PF) applied on dentine pre-treated with ED Primer (ED) and Clearfil Liner Bond 2V (CLB) coated with a layer of low-viscosity composite Protect Liner F (PLF) at 10min, 24h and 12 months after curing.

Methods

The labial surfaces of 60 bovine lower incisors were ground to obtain a flat dentine surface, allowing a demarcation of a 4.0mm-diameter area with adhesive tape. The teeth were randomly divided in six groups; ED was applied in groups A I, A II and A III and CLB was applied, followed by PLF, in groups B I, B II and B III. A resin composite rod with a wire loop was luted directly to the prepared surface of each group with PF. The specimens of groups A I and B I were submitted to TBS test after 10min. Groups A II and B II were submitted to TBS test after 24h storage and groups A III and B III were submitted to TBS test after 12 months storage. Each specimen was inspected by SEM and classified according to the failure mode. Additionally, two representative specimens of each failure mode were sectioned for a composite/dentine interface SEM evaluation.

Results

No significant statistical differences were observed among the groups at 10min and 24h. Groups A III and B III presented the lowest TBS values (p<0.05) after 12 months storage. PF on resin-coated dentin (PLF) showed the highest TBS values and was statistically different to PF on dentine for all the groups. The fracture pattern was generally cohesive on the adhesive/hybrid layer for groups A I, A II and A III and cohesive on composite resin for B I, B II and B III.

Significance

The use of a less hydrophilic self-etching system to pre-treat dentine, coating with a low-viscosity composite layer prior luting with resin cement, may provide a protection of the hybridised complex, allowing a dentine seal during the 12 months storage period.

Keywords: Bonding, Self-etch adhesive, Resin cement, Durability, Tensile bond strength