Current Status of Adhesive Materials and Technologies in Direct Composite Restorations.

The conventional three-step adhesive system is composed of an etchant, a primer, and a bonding resin. Japanese manufacturers focused on simplifying the etching and priming procedures, resulting in a one-step process referred to as "self-etching". Currently, a universal adhesive system and a universal-shade composite are trending. Morphological changes at the interface of the bonded specimens following an artificial acid-base challenge have been observed under SEM and TEM. A new layer is created beneath the hybrid layer, which is referred to as the "acid-base resistant zone (ABRZ)". With the increasing number of older adults and better teeth retention in the elderly population, the prevention and treatment of root caries are becoming increasingly important. 38% silver diamine fluoride (SDF, Saforide) contains high concentrations of silver and fluoride ions, which is very effective in preventing the progression of root dentin caries. However, the discoloration of the tooth structure is a drawback. It was reported that light exposure and demineralization of dentin accelerated its discoloration. From the evaluation of S. mutans biofilm accumulation on dentin surfaces, application of 38% SDF was the most effective to decrease the amount of biofilm attached to the dentin surface. In addition, 38% SDF has the potential to be used as a root caries indicator. From the clinical assessment, the SDF induced discoloration of the root caries lesions and provided an anti-inflammatory effect on the gingiva around the teeth affected by root caries. [ABSTRACT FROM AUTHOR]