Rise in pulp temperature during finishing and polishing of resin composite restorations: an in vitro study

The aim of this study was to establish the effects of the working speed, the use of coolant, and the pressure applied on the temperature of the pulp when resin composite restorations are finished and polished. One hundred eighty teeth with resin composite restorations are finished and polished. One hundred eighty teeth with resin composite restorations were randomly distributed into groups to be finished and polished with violet, blue, or yellow flexible disks. Each group was randomly subdivided into six subgroups of 10 each. Four subgroups were finished and polished, without water cooling, under constant pressure at speeds of 10,000, 8,000, 6,000 or 4,000 rpm. The other two subgroups were finished and polished at 10,000 rpm, one without water cooling while work was carried out intermittently and the the other with water cooling while work was carried out constantly. Results implied that a maximal speed of 4,000 rpm should be applied when polishing is carried out continuously without water coolant. When water cooling is used, flexible disks can safely be used at a speed of 10,000 rpm and with continuous pressure.