Dentin as a bonding substrate

Dentin comprises the largest dental structure available for bonding. Because of its inherent morphological and physiological characteristics, reliable and durable resin–dentin bonding remains a challenging accomplishment that is subjected to multi‐factorial interferences. Adhesive technology has evolved significantly over the past decade, resulting in improved predictability of resin–dentin bonds. This article reviews the present knowledge regarding resin–dentin bonding from the perspective of the dentin substrate. Since another article in the previous issue of E ndodontic T opics already covers dentin structure and composition, the intention is not to fully review these aspects. Instead, basic principles of current bonding strategies used by adhesive agents are presented. Specific attention is given to describing how the morphology and physiology of dentin affect existing bonding mechanisms, how some chemical treatments of dentin can affect its properties and bonding, and finally how bonding to root canal dentin is currently viewed and understood.