Chemical and mechanical degradation of nano-ionomer after two different surface protections: An in vitro study.

Purpose: To evaluate the effect of food-simulating liquids prior to brushing on surface roughness of a nano-ionomer restorative protected with two surface protection agents.

Methods: 90 specimens were divided into three groups according to surface protection; the first group: no surface protection; the second group: copal varnish; the third group: light cure Ketac Glaze. Each group was subdivided into three subgroups relative to the immersion solution: artificial saliva; citric acid 0.