Development of Dentin Adhesives

Begun in the 1950s, research on dentin bonding continued at a slow pace through the 1960s and 1970s and culminated in the introduction of the first commercial dentin adhesive in 1975 [85]. However, this product had very poor clinical results when used to restore cervical erosion lesions without mechanical retention [98], 

A third generation of adhesives was introduced in the mid- to late 1980s, and these either modified or removed the smear layer to permit resin penetration into the underlying dentin [107,108]. However, they did not even nearly approach the desired goal of 100% retention [109,110]. 

---