Increases of intracanal and root surface temperatures during the obturation of canal using the E&Q Master System and the System B.

Objectives: The purpose of our study is to assess the increases of intracanal and root surface temperatures during the obturation of canal system using the E&Q Master System and the System B. Materials and methods: A split-tooth model was built. To measure the temperature, 6 grooves for the placement of thermocouples were made in the buccal half of the model. On the mesial side, three grooves were made at 2, 4 and 6 mm from the anatomical apex and were extended to the root surface, while on the distal side three grooves were made at 2, 4 and 6 mm up to the intracanal portion. In each of these grooves was inserted a type T thermocouple (Copper-Costantana) with a diameter of 0.076 mm. 40 canal obturations were done: 20 using the E&Q Master System and 20 using the System B, set at 250 °C, both with plugger FM increased to 3.5 mm from WL. The temperatures were recorded at 1 s intervals for a period of 200 s. Results: During the continuous wave obturation technique two peaks in temperature occurred, the first caused by the plugger in the canal, the second during the separation phase. In the E&Q Master System the highest increases were recorded in the thermocouple N.6, which reported average increases of 6.30 °C, while the lowest were recorded in the thermocouple N.1, which reported a value of 2.11 °C. In the System B group the highest increases were recorded in the thermocouple N.6, which reported average increases of 2.80 °C, while the lowest were recorded in the thermocouple N.1, which reported a value of 0.4 °C. Conclusions: Analysis of the obtained results showed that both systems allow us to get a good thermal mass increase of gutta-percha. Results show that the use of E&Q Master System and System B, in vitro, appears to cause a dangerous increase in temperature along the surface of the root that may create iatrogenic injury.