Nadkarni M A, Angner K, Hunter N
Institute of Dental Research, Westmead Centre for Oral Health and The Westmead Institute for Medical Research, The University of Sydney, Westmead, Australia.
Faculty of Dentistry, The University of Sydney, Sydney, New South Wales, Australia.
Eur J Clin Microbiol Infect Dis. 2017 May;36(5):869-878. doi: 10.1007/s10096-016-2875-6. Epub 2016 Dec 24.
The objective of the present study was to test the hypothesis that nutrient deprivation by effective isolation should inactivate causative saccharolytic bacteria occupying carious lesions. Vital maxillary third molar teeth were prepared by removing only the superficial necrotic material, leaving behind infected dentinal matrix, before the cavity was sealed with glass ionomer cement (GIC). Before sealing, lesions were biopsied to provide reference bacterial DNA for microbial analysis. After an interval of 10-12 months, the teeth were extracted and, after careful removal of GIC restoration, the underlying dentine was biopsied again for post-treatment microbial analysis. Microbial diversity for nine taxa in 45 carious lesions, before and after minimal intervention therapy, was quantified by real-time polymerase chain reaction (PCR). Except for Propionibacterium sp. FMA5, Fusobacterium nucleatum and Pseudoramibacter alactolyticus, representation of all other taxa showed reduction in the post-restoration biopsy samples. However, Propionibacterium sp. FMA5 was the only species predominantly detected in 80% of the pre-intervention, 82% of the post-restoration and 73% of the paired pre- and post-restoration biopsy samples. The median bacterial load for Propionibacterium sp. FMA5, lactobacilli and bacteria from the family Coriobacteriaceae was higher than the median bacterial load for the remaining six taxa. Significant reduction in the median bacterial load for lactobacilli was evident in post-restoration biopsy samples, implying effective control by GIC after minimal intervention. However, the median bacterial load for Propionibacterium sp. FMA5 increased in post-restoration biopsy samples. Incorporation of antimicrobial agents effective against Propionibacterium species FMA5 could add to more effective conservative management of advanced carious lesions.
通过有效隔离造成营养缺乏应能使占据龋损部位的致病性解糖细菌失活。对上颌第三恒磨牙仅去除表面坏死物质，保留感染的牙本质基质，然后用玻璃离子水门汀（GIC）封闭窝洞。封闭前，对病变组织进行活检以提供用于微生物分析的参考细菌DNA。间隔10 - 12个月后，拔除牙齿，小心去除GIC修复体后，再次对下方牙本质进行活检以进行治疗后微生物分析。通过实时聚合酶链反应（PCR）对45个龋损部位在最小干预治疗前后9个分类群的微生物多样性进行定量分析。除丙酸杆菌属FMA5、具核梭杆菌和非解乳糖假枝杆菌外，所有其他分类群在修复后活检样本中的表现均显示减少。然而，丙酸杆菌属FMA5是唯一在80%的干预前、82%的修复后以及73%的配对干预前和修复后活检样本中均占主导地位检测到的菌种。丙酸杆菌属FMA5、乳酸杆菌以及科里杆菌科细菌的细菌载量中位数高于其余6个分类群的细菌载量中位数。修复后活检样本中乳酸杆菌的细菌载量中位数显著降低，这意味着最小干预后GIC起到了有效控制作用。然而，丙酸杆菌属FMA5的细菌载量中位数在修复后活检样本中有所增加。加入对丙酸杆菌属FMA5有效的抗菌剂可能会使对晚期龋损的更有效保守治疗得以加强。
