At the beginning of the century the radical approach to treatment of an occlusal surface carie of a molar were related to the principles developed by G.V. Black. Extension for prevention in the occlusal fissures, whether they were decayed or not, respected the needs of that era. Those ideas were based on the epidemiology of dental caries and mechanical properties of the filling materials in use to treat them. The parameters of treatment have changed, the reality is not the same. Nowadays, conservative composite resin restorations, demand a less destructive approach for small carious pit and fissure lesions in both the primary and permanent dentitions.