Sanai Yasaman, Persson G Rutger, Starr Jacqueline R, Luis Henrique S, Bernardo Mario, Leitao Jorge, Roberts Marilyn C
Department of Periodontics, University of Washington, Seattle, Washington 98195, USA.
J Clin Periodontol. 2002 Oct;29(10):929-34. doi: 10.1034/j.1600-051x.2002.291008.x.
BACKGROUND/AIMS: Only limited information exists about the prevalence in children of pathogens associated with periodontitis. The aim of the present study was to determine by culture whether 8-11-year-old children carry Porphyromonas gingivalis, Prevotella intermedia, and/or P. nigrescens in samples from the gingiva and/or the buccal mucosa taken before, and after caries treatment and oral hygiene instruction. A second aim was to assess the proportion of subjects who had gram-negative anaerobes carrying the tet(Q) and erm(F) genes, suggesting antibiotic resistance to tetracycline or erythromycin.
A total of 150 children provided gingival and buccal swab bacterial samples that were cultured for P. gingivalis, P. intermedia, and P. nigrescens. The species was verified using DNA-DNA hybridization with species-specific probes made from the variable region of the 16S rRNA sequences. Antibiotic-resistant genes, tet(Q) and erm(F), were identified using specific DNA-DNA hybridization with specific DNA probes.
A total of 116 isolates of black-pigmented bacteria were cultured from 47 (31%) of 150 children. Five isolates were identified as P. gingivalis, 29 as P. intermedia, 33 as P. nigrescens, and 49 as other species. In general, the bacteria were not culturable at more than one time period. We found that 55% of these 47 children harbored black pigmented bacteria that carried either one or both of the two antibiotic-resistant genes studied (tet(Q), and erm(F)).
The present study demonstrated that children not exposed to regular dental treatment carry bacteria outside the gingival sulcus that have been associated with periodontitis, and that standard treatment procedures may not clear the presence of the putative pathogens. In addition, antibiotic-resistant genes are common in identifiable gram-negative anaerobes, including putative pathogens.
背景/目的：关于与牙周炎相关的病原体在儿童中的流行情况，现有信息有限。本研究的目的是通过培养，确定8至11岁儿童在龋齿治疗和口腔卫生指导前后采集的牙龈和/或颊黏膜样本中是否携带牙龈卟啉单胞菌、中间普氏菌和/或变黑普氏菌。第二个目的是评估携带tet(Q)和erm(F)基因的革兰氏阴性厌氧菌的受试者比例，这表明对四环素或红霉素具有抗生素抗性。
共有150名儿童提供了牙龈和颊拭子细菌样本，用于培养牙龈卟啉单胞菌、中间普氏菌和变黑普氏菌。使用与由16S rRNA序列可变区制成的物种特异性探针进行DNA-DNA杂交来验证物种。使用与特定DNA探针进行的特定DNA-DNA杂交来鉴定抗生素抗性基因tet(Q)和erm(F)。
从150名儿童中的47名（31%）培养出总共116株黑色色素细菌分离株。5株分离株被鉴定为牙龈卟啉单胞菌，29株为中间普氏菌，33株为变黑普氏菌，49株为其他物种。一般来说，这些细菌在多个时间段内无法培养。我们发现，这47名儿童中有55%携带了携带所研究的两种抗生素抗性基因（tet(Q)和erm(F)）中的一种或两种的黑色色素细菌。
本研究表明，未接受定期牙科治疗的儿童在牙龈沟外携带与牙周炎相关的细菌，并且标准治疗程序可能无法清除假定病原体的存在。此外，抗生素抗性基因在可识别的革兰氏阴性厌氧菌中很常见，包括假定病原体。
