Abstract
This study investigated the impact of a separate silanization step on the repair bond strength of composite substrates using a universal adhesive after various mechanical surface treatments. Composite specimens were aged and exposed to the following mechanical roughening treatments: diamond bur abrasion, aluminum oxide sandblasting, or silica coating. The specimens were then either left untreated or conditioned with universal adhesive (Scotchbond Universal), or a silane coupling agent was applied before the use of the universal adhesive or a conventional adhesive (Optibond FL). The conditioned surfaces and fresh substrate (positive control group) were covered with repair composite, and microtensile bond strength testing was performed. The significantly highest bond strength was obtained in the positive control group. Repair bond strength of the universal adhesive applied after a separate silanization step was similar to that without prior silanization, independent of the mechanical surface treatment. Moreover, after silica coating, no significant differences in the repair bond strength were detected among the different adhesive treatments. In conclusion, a separate silanization step before surface conditioning with the universal adhesive does not enhance the repair bond strength. On silica-coated composite substrates, repair bond strength values of the universal adhesive were similar to those of the conventional adhesive.
Highlights
Nowadays, resin-based composite is the most frequently used restorative material worldwide [1].Despite the immense progress over the last decades concerning physical and mechanical properties [2,3,4,5,6,7], resin-based composite restorations still fail mainly because of fractures or secondary caries [8,9].The question arises whether to replace or to repair the partially insufficient restoration
After diamond bur abrasion or sandblasting with aluminum oxide, the conventional adhesive in combination with a abrasion or sandblasting with aluminum oxide, the conventional adhesive in combination with a silane coupling agent reached significantly higher bond strength values than the universal adhesive silane coupling agent reached significantly higher bond strength values than the universal adhesive applied without prior silanization (p < 0.001 and p = 0.016, respectively)
After separate silanization, no significant differences in repair bond strength were revealed between the universal silanization, no significant differences in repair bond strength were revealed between the universal adhesive and the conventional adhesive
Summary
Resin-based composite is the most frequently used restorative material worldwide [1].Despite the immense progress over the last decades concerning physical and mechanical properties [2,3,4,5,6,7], resin-based composite restorations still fail mainly because of fractures or secondary caries [8,9].The question arises whether to replace or to repair the partially insufficient restoration. Despite the immense progress over the last decades concerning physical and mechanical properties [2,3,4,5,6,7], resin-based composite restorations still fail mainly because of fractures or secondary caries [8,9]. Repair restorations have several advantages over replacements, as they are less time and cost intensive. They preserve sound tooth tissue and decrease the risk of pulp irritation, and represent a minimal-invasive treatment approach to increase the longevity of restorations [10,11,12,13,14,15].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
