Continuous Wave of Condensation Technique으로 근관충전시 치근면 온도상승 분석 = Analysis of Temperature Rise on the Root Surface during Continuous Wave of Condensation Technique

다국어 초록 (Multilingual Abstract)

This study was conducted to evaluate safety to the supporting tissues of the root while the root canal is obturated using continuous wave of condensation technique.
A extracted maxillary central incisor was prepared for repeated canal obturation. After conventional access opening, working length was then established to the point 1㎜ from anatomical root apex. The root canal was prepared with GT rotary Ni-Ti file (Dentsply Maillefer, Switzerland).
Five thermocouples (Onega Engineering Inc., USA) were placed at 2㎜ increments on one side beginning 1㎜ from the anatomical root apex and the other five thermocouples at 2㎜ increments on the other side beginning 2㎜ from it. For obturation, a nonstandardized medium size gutta-percha cone and a ML Buchanan plugger (Analytic technologies, USA) were selected. After drying of root canal, AH 26 root canal sealer (Dentsply Detrey, Germany) was applied on the wall of the root canal.
Baseline temperature was measured on the root surface. The ML size plugger was preheated for 2seconds and then the real temperature of it was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan. The root surface temperature was recorded during obturation and it was performed ten times at each of the following temperature settings: 150℃, 200℃, 250℃ and 300℃. After completion of the temperature recording, the dentinal-cementum thickness at each sites where thermocouples were attached was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test.
The results were as follows.
1. When the temperature was set at 150℃, 200℃, 250℃ and 300℃ on the digital display of System B HeatSource, the real temperature of the plugger at the 1㎜ point from the tip revealed 130.82±2.96℃, 158.00±5.26℃, 215.92±6.91℃ and 249.88±3.65℃ respectively.
2. The position of 8 ㎜ from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.01). The temperature rise was constantly increased toward coronal portion from apex of the root.
3. The maximum temperature increase on the root surface was 2.37±0.09℃ at 150℃ setting, 3.11±0.12℃ at 200℃ setting, 3.93± 0.09℃ at 250℃ setting and 5.69± 0.15℃ at 300℃ setting.
These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at 150℃, 200℃, 250℃ and 300℃ temperature settings on digital display of System B HeatSource.