One of the most conservative ways to retain tooth structure, preserve pulpal health, and avoid invasive treatment is to simply completely seal established carious lesions. A tight seal to isolate the biofilm and arrest the lesion can be successfully achieved using a sealant material such as resin or glass-ionomer for non-cavitated lesions, a restorative material for cavitated lesions, or, for primary teeth, preformed stainless-steel crowns. This chapter focuses on sealants and restorative materials. Sealant materials are a viable treatment option for controlling non-cavitated lesions in occlusal and proximal surfaces where there is no significant breach in the surface integrity of the tooth, even if the lesion extends into dentine. Resin in...