The effect of cooling techniques on intrapulpal temperature during direct fabrication of provisional restorations

In vitro measurements were made of the heat transferred to the pulp chamber during the direct fabrication of extracoronal provisional restorations. The temperature was monitored for the following four groups: (1) control--the provisional restoration was left on the tooth with no coolant used; (2) removal--the provisional restoration was removed upon initial resin polymerization; (3) in situ--the provisional restoration was left in place and cooled with an air/water spray; and (4) on/off--the provisional restoration was repeatedly removed and replaced upon initial polymerization while using an air/water spray. The intrapulpal temperature rises were as follows: control 7.08 degrees C, removal 2.39 degrees C, in situ 2.36 degrees C, and on/off 3.12 degrees C. The temperature rise for all cooling techniques was significantly lower than that of the control. No significant differences were found between the three cooling techniques.