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

摘要

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 temper-ature should be used for individual tooth.%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。