This fact is from Dental Bonding Agents — Generations in Conservative Dentistry & Endodontics. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Total etch = 4th and 5th generation gold standard
Self-etch = 6th and 7th generation
5th gen = one bottle most popular
7th gen = all-in-one self-etch
Etch and rinse still best for enamel bonding
Smear layer removed in total etch
Smear layer modified in self-etch
Hybrid layer = resin infiltrated dentin.