B＆L热塑系统不同温度充填根管引起牙根表面温度变化的研究

Changes of root surface temperature caused by different filling temperatures with B&L system heat source

目的:分析不同温度热塑牙胶充填时牙根表面的温度变化。方法:纳入单根管牙60个,分别截除牙冠并预备根管后,用藻酸盐印模材料均匀包绕各牙根。用B&L热塑系统分别以230、200、180℃的温度进行根管充填,并用热电偶分别测量各牙根上部、根中部、根尖上4 mm处的牙根表面温度变化;然后分别在上述3个检测点处截开牙根,并测量其各位置1.0、1.5、2.0 mm根管壁厚度的温度变化。结果:230、200℃充填时,部牙根上部表面的温度升高平均值均超过10℃。不同温度充填时,冠部牙根表面温度两两相比P<0.05;根中和根尖上方4 mm处,230℃充填时分别与180、200℃相比P<0.05。同一充填温度时,牙根表面3个测量点温度升高值两两相比P<0.05。300、200℃充填时,各部位牙根表面温度升高值1.0、2.0 mm组相比P<0.05;180℃充填时,3种厚度根管壁无统计学差异(P>0.05)。结论:对于根管壁较薄的牙,应适当降低充填温度。

AIM： To observe the changes of root surface temperature with different root filling temperatures. METHODS： 60 permanent teeth with single canal were used. After crown removal and root canal preparation the teeth were instrumented and subsequently embedded in alginate. 3 holes were made into the alginate at levels the cementoe- namel junction, mid-root, and 4 mm to apex to allow access for the temperature probes. Obturations were made at 180 ℃, 200 ℃ and 230℃respectively, the temperature was measured at each position. Then the teeth were sectioned using a fine sandpaper disk, and the remaining dentin thickness was measured. RESUITS： When the temperature set- tings were 200℃ and 230℃, the temperature rise at the cementoenamel junction exceeded 10℃. At the remaining den- tin thickness of 1 mm group, significant difference in temperature rise was found among the 3 filling temperature settings （ P 〈 0.05） and among the 3 temperature measurement sites （P 〈 0.05 ）. When the root canals were obturated at 200℃ or 230℃, significant difference was found in the change of root surface temperature between dentin - thickness 1.0 mm group and 2.0 mm group at the cementoenamel junction （P 〈 0.05）. However, when the root canals were obturated at 180℃, no difference was found among the 3 measurement depths （P 〉0. 05）. CONCLUSION： Suitable filling temperature should be used for individual tooth.