全冠牙体预备后局部龈沟菌群的变化

THE CHANGES OF GINGIVAL CREVICULAR FLORA AFTER TOOTH PREPARATION OF FULL CROWN

目的 :定量观察临床全冠修复患者牙体预备完成 1w内 ,其龈沟菌丛的变化。方法 :选择 14颗需进行全冠修复的第一磨牙作为研究对象 ,以同颌同名牙作为研究对照 ,分别采集牙体预备前、预备后 72h及 1w时 ,预备牙和同颌同名牙龈沟菌丛的标本。经细菌接种、厌氧培养、生化鉴定 ,进行可培养菌计量。比较同一时期预备牙龈沟菌丛与同颌同名牙龈沟菌丛间 ,以及不同时期预备牙龈沟菌丛间可培养菌量的变化。结果 :(1)牙体预备后 1w内 ,预备牙龈沟菌丛中多数细菌菌量接近或超过预备前水平 ,差异无显著性 (P>0 .0 5 ) ,但以放线菌为主的 G+性杆菌增多明显。(2 )同一时期以放线菌为主要的 G+杆菌和奈瑟菌的菌量在预备牙龈沟菌丛和同颌同名牙龈沟菌丛间差异有显著性 (P<0 .0 5 )。结论 :(1)牙体预备后 ,预备牙龈沟菌丛的自然变化过程 ,与天然牙菌斑形成过程相似 ,其龈沟菌丛菌量和菌种随时间的延长而增多。 (2 )预备牙龈沟菌丛和同颌同名牙龈沟菌丛间以放线菌为主的 G+杆菌和奈瑟菌差异有显著性 (P<0 .0 5 )。

Objective: This study intends to investigate the changes of the quantity of bacteria in gingival sulcus after one week of tooth preparation for full crown.Methods:Seven first molars which ought to accept full-crowns were selected.The gingival crevicular flora were collected before tooth preparation,72 hours and one week after preparation respectively.After inoculation,anaerobic incubation,chemical identification, the quantities of cultivable flora were recorded.Results:(1)Within one week after tooth preparation,the quantity of most cultivable flora remained the same level as or became more than that before operation.There were no significant statistical differences among these values.While the quantities of gram positive bacilli,especially actinomyces,increased predominantly.(2)Within the same period,there no significant statistical differences,increased predominantly.(2)Within the same period,there were significant statistical differences between the operative tooth and the control tooth,in the quantities of the gram positive bacilli(actinomyces major) and neisseria.Conclusion:(1)Plaque in the operative area has the same mature course as the natural plaque.The quantities of cultivable flora grow bigger and the detected species become more and varied with time.(2)Compared with the control tooth,the amounts of gram positive bacilli and neisseria in the operative tooth have significant differences.