European Journal of Molecular & Clinical Medicine ISSN 2515-8260 Volume 07, Issue 09, 2020 30 EVOLUTION of DENTIN BONDING AGENTS Dr. Niladri Maiti# 1 , Dr. Duran Kala 2 & Dr. Alisir Babakuliyev 3 #1 Associate Professor, Department of Endodontics, Faculty of Dentistry, Tishk International University, Erbil, Kurdistan Region, Iraq 2 Lecturer & Dean, Faculty of Dentistry, Tishk International University, Erbil, Kurdistan Region, Iraq 3 Asst Lecturer, Department of Endodontics, Faculty of Dentistry, Tishk International University, Erbil, Kurdistan Region, Iraq # niladri.maiti@tiu.edu.iq Abstract: This article describes the different types of bonding agents and its concepts of bonding to enamel, dentin, cementum. This also gives idea about different types of changes in chemical composition of bonding agents which varies between different generations. It also emphasizes about the importance of etchants and primers. Keywords: Dentin bonding agents, Enamel Bonding, Cementum Bonding, generations of bonding agents, acid-etchant, primer. INTRODUCTION There are various materials available in dentistry like metallic or non metallic, aesthetic material or non aesthetic material,bonded or non bonded restorative material . Esthetic dental appearance is one of the patients’ demands. This helped in the evolution of esthetic restorations, including the use of resin-based composite materials..Composite resin do not show an intimate microscopic contact with dentin when placed directly into the cavity. In order to overcome this, an intervening layer of fluid is used, which fills in the microscopic space, polymerizes and combines with the composite resin and components of dentin and thereby reducing microleakage. The history of dental adhesives started as early as 1949, when Dr. Hagger, a Swiss chemist who patented a ―Cavity Seal‖ material (glycerolphosphoric acid dimethacrylate) used in combination with the chemically curing resin ―Sevriton‖, in 1951. Only dentin was initial substrate for bonding not the enamel. In 1952, it was postulated by Mclean and Kramer, that this material, ―Sevriton Cavity Seal‖, chemically bonded to tooth structure. [1] Decade Bonding agent introduced 1960s First generation 1970s Second generation 1980s Third generation Early 1990s Fourth generation Mid-1990s Fifth generation Late 1990s Sixth generation Early 2000s Seventh generation 2010 Eight generation 2011 Universal bonding agent