IngentaConnect Intracanal temperature rise evaluation during the usage of the Sy...

Abstract:

Villegas JC, Yoshioka T, Kobayashi Ch, Suda H. Intracanal temperature rise evaluation during the usage of the System B: replication of intracanal anatomy. International Endodontic Journal, 38, 218–222, 2005. Abstract Aim

To evaluate and determine intracanal temperature rises at 2 and 4 mm from the working length (WL) necessary to obtain proper replication of intracanal anatomy with gutta-percha (GP) using the System B heat source during vertical condensation. Methodology

A split-tooth model was prepared and artificial shallow depressions were cut in the buccal canal wall 2 and 4 mm from the WL. At the same level on the palatal wall holes were drilled to adapt two thermocouples. The canal was filled using GP in a vertical condensation technique by placing the System B plugger at 2 and 4 mm from the WL in groups A and B, respectively. Two control groups in which no GP was used were carried out placing the plugger 2 and 4 mm from the WL (groups A.c and B.c, respectively) and activating the heat source. Recording of temperature rise was carried out during the filling procedure for groups A and B and during activation for control groups A.c and B.c; the highest temperatures were recorded. After each filling was completed, 3 min were allowed for the GP to cool and the model divided to reveal the filling. Images of the GP were taken with a CCD camera to evaluate the presence of replication of artificial round depressions. In control groups, the temperature was recorded for 20 s after a 3 s activation of the heat source. The rise in temperature was compared between the groups individually at each level (2 or 4 mm) and statistically analysed using one-wayanovaand Fisher PLSD tests at 5% of significance level (P < 0.05). Results

Mean temperature rises of 14 ± 3 and 12 ± 2 °C at 2 and 4 mm from the WL, respectively, were observed in group A fillings, and 4 ± 1 and 6 ± 1 °C at 2 and 4 mm, respectively, in group B fillings. Recordings at 2 mm showed significantly (P < 0.05) higher temperature rises with group A.c when compared with groups B and B.c. Replication of intracanal anatomy with GP was always found in group A fillings at both levels but only 4 mm from the WL in group B fillings. Conclusions

Positioning the plugger close to WL and a temperature rise of 6 °C were necessary to obtain replication of intracanal anatomy. A mean temperature rise of 4 °C at 2 mm from WL (group B) resulted in no replication of intracanal anatomy. Further studies simulating clinical conditions are necessary.