Casas Agustín, Herrera David, Martín-Carnes Javier, González Itziar, O'Connor Ana, Sanz Mariano
Section of Graduate Periodontology, Faculty of Odontology, University Complutense, Madrid, Spain.
J Periodontol. 2007 Jun;78(6):1103-12. doi: 10.1902/jop.2007.060232.
The aim of this study was to test whether different sampling strategies would influence the microbiologic outcomes by assessing the bacterial load and composition of the subgingival microbiota by means of anaerobic culturing before and after periodontal treatment.
The first study (1 versus 4 [1vs4]) included 33 patients with generalized chronic periodontitis. Two sampling strategies were compared, sampling one site from the deepest pocket in the mouth (M1) versus a pooled sample of four sites from the deepest pockets in each quadrant (M4). The second study (2 versus 4 [2vs4]) included 20 patients with generalized chronic periodontitis. The strategy M4 was compared to a pooled sample of two non-adjacent sites in the same quadrant (M2). All samples were processed identically by means of anaerobic culturing. In both studies, a pretreatment sampling was taken. However, in the second study (2vs4), subgingival samples were also taken at 1, 3, and 6 months after periodontal therapy. Quantitative data were compared between strategies by means of t test and signed-rank test; qualitative data were compared by means of 2 x 2 contingency tables.
Pretreatment samples showed that total anaerobic counts were significantly higher for M4 compared to M1 (P <0.001) and M2 (P = 0.025). However, there were no significant differences in regard to percentage of microbiota and counts for each pathogen. Most of the qualitative differences between strategies were caused by false negatives in M1 and M2. Post-treatment samples showed a reduction in total counts and a limited impact in the frequency of detection of periodontal pathogens. M2 detected a significant decrease in the frequency of detection of Porphyromonas gingivalis, which was not confirmed by the M4 strategy.
The criteria of selection and the number of sites selected when sampling the subgingival biofilm in patients with generalized chronic periodontitis may influence the detection and quantitation of periodontal pathogens when evaluated by culture especially after treatment.
本研究旨在通过在牙周治疗前后采用厌氧培养法评估龈下微生物群的细菌载量和组成，来测试不同的采样策略是否会影响微生物学结果。
第一项研究（1个位点与4个位点[1vs4]）纳入了33例广泛性慢性牙周炎患者。比较了两种采样策略，即从口腔最深牙周袋中采集1个位点的样本（M1）与从每个象限最深牙周袋中采集4个位点的混合样本（M4）。第二项研究（2个位点与4个位点[2vs4]）纳入了20例广泛性慢性牙周炎患者。将M4策略与同一象限中2个不相邻位点的混合样本（M2）进行比较。所有样本均通过厌氧培养进行相同处理。在两项研究中，均进行了治疗前采样。然而，在第二项研究（2vs4）中，还在牙周治疗后的1、3和6个月采集了龈下样本。通过t检验和符号秩检验对不同策略之间的定量数据进行比较；通过2×2列联表对定性数据进行比较。
治疗前样本显示，与M1（P<0.001）和M2（P = 0.025）相比，M4的总厌氧菌计数显著更高。然而，在微生物群百分比和每种病原体的计数方面没有显著差异。不同策略之间的大多数定性差异是由M1和M2中的假阴性引起的。治疗后样本显示总数减少，对牙周病原体检测频率的影响有限。M2检测到牙龈卟啉单胞菌的检测频率显著降低，而M4策略未证实这一点。
在对广泛性慢性牙周炎患者的龈下生物膜进行采样时，选择标准和所选位点的数量可能会影响通过培养评估时牙周病原体的检测和定量，尤其是在治疗后。
