寻根管口入路开髓法对老年人离体磨牙开髓的效果

The Effect of Opening the Pulp Chamber of the Isolated First Molars of the Old Patients with Access Technique of Looking for Canal Orifice

目的探讨寻根管口入路开髓法在老年人离体上下第一磨牙上进行开髓的效果。方法准备形态基本完整的老年人离体第一磨牙160个（每个牙位40个）。反2005～2007年在口腔科实习新生中随机抽取160人作为开髓操作者。将其均分为两组：寻根管口入路法开髓组80人，找髓角入路法开髓组80人。然后每一实习生随机抽取用纸密封的第一磨牙1个。由口腔医生将此牙固定在标准牙弓的阴模的该磨牙相应位置处，灌普通石膏模型，并将普通石膏模型固定在仿真头颅模型上，并按开髓常规调节好椅位和光源。由口腔医生按统一要求为实习生培训所在组别的开髓方法，并通过考核确认其已掌握了该开髓方法。实习生用所在组的方法在头颅模型上独立地进行开髓。开髓完成后由口腔医生按开髓效果评定标准进行效果评定。结果实验组有效率为92．5％，对照组有效率为75．0％，经统计学分析差异有高度显著性。结论口腔实习生在老年人离体第一磨牙上开髓用寻根管口入路开髓法比用找髓角入路开髓法成功率更高。

Objective To investigate the effect of opening the pulp chamber of isolated upper and lower first molars of the old patients with access technique of looking for canal orifice. Methods 160 isolated first molars of the old patients （40 first molars on each position ） with proper shape were prepared. From 2005 to 2007,160 operators were randomly selected from stomatologieal practise students, and divided into two groups ： experimental group （ opening the pulp chamber with access technique of looking for canal orifice ） with 80 operators , control group （ opening the pulp chamber with access technique of looking for pulp horn） with 80 operators. Every operator randomly select one parked first molar from 160 first molars. A stomatologist was responsible for stieking the selected teeth to the proper position of the first molar in normal dental impression,pouring the plaster cast, and after solidified the stomatologist stieked the plaster east to a cranial model and adjusted the position of dental chair and lighting. The stomatologist didn ＇ t teach the operator about the method of opening the chamber until the operator passed the theoretical examination, then every operator fulfilled the task of opening the chamber by himself. The stomatologist evaluated the effect of opening the chamber by the operator , extracted data and performed a statistical analysis. The stomatologist mentioned above is the same person. Results Effective rate of experimental group is 92.5% , effective rate of the control group is 75.0%. which has significant differences by statistical analysis （ P 〈 0.005 ）. Conclusion The results suggest that opening the chamber of the isolated first molar of the old patient with access technique of looking for canal orifice is more effective than with access technique of looking for pulp horn.