BisCover LV is indicated for use on top of a resin-modified glass ionomer, but it cannot be used on traditional glass ionomers. The reason is that BisCover LV cannot bond to traditional GI because its hydrophobic components are not compatible with GI's highly hydrophilic surface. However, BisCover LV can bond to RMGI via its chemical bonding to light-cured polymers, overcoming the hydrophobic-hydrophilic incompatibility.