Haubek Dorte, Ennibi Oum-Keltoum, Poulsen Knud, Vaeth Michael, Poulsen Sven, Kilian Mogens
Department of Community Oral Health and Pediatric Dentistry, University of Aarhus, Denmark.
Lancet. 2008 Jan 19;371(9608):237-42. doi: 10.1016/S0140-6736(08)60135-X.
Periodontitis is a loss of supporting connective tissue and alveolar bone around teeth, and if it occurs in an aggressive form it can lead to tooth loss before the age of 20 years. Although the cause of periodontitis in general remains elusive, a particular clone (JP2) of the gram-negative rod Aggregatibacter (Actinobacillus) actinomycetemcomitans is considered a possible aetiological agent of the aggressive form in adolescents living in or originating from north and west Africa, where the disease is highly prevalent. We did a population-based longitudinal study of adolescents to assess the role of the JP2 clone in the initiation of aggressive periodontitis.
A total of 700 adolescents from public schools in Rabat, Morocco, were enrolled in the study. We used PCR to detect A actinomycetemcomitans in plaque samples (taken from molar and incisor sites) and to differentiate between the JP2 clone and other non-JP2 genotypes of the bacterium. 18 individuals were found to already have periodontitis and were excluded. The 682 periodontally healthy adolescents (mean age 12.5 years; SD 1.0) were classified according to their A actinomycetemcomitans carrier status at baseline. After 2 years, 428 (62.8%) individuals returned for re-examination, which included recording of periodontal attachment loss measured from the cemento-enamel junction to the bottom of the periodontal pockets of all teeth present.
Individuals who carried the JP2 clone of A actinomycetemcomitans alone (relative risk 18.0; 95% CI 7.8-41.2, p<0.0001) or together with non-JP2 clones of A actinomycetemcomitans (12.4; 5.2-29.9, p<0.0001) had a significantly increased risk of periodontal attachment loss. A much less pronounced disease risk was found in those carrying non-JP2 clones only (3.0; 1.3-7.1, p=0.012).
The JP2 clone of A actinomycetemcomitans is likely to be an important aetiological agent in initiation of periodontal attachment loss in children and adolescents. Co-occurrence of non-JP2 clones of A actinomycetemcomitans reduces the risk of development of periodontitis, suggesting competition for the ecological niche between the JP2 and non-JP2 clones of this species.
牙周炎是牙齿周围支持性结缔组织和牙槽骨的丧失，如果以侵袭性形式发生，可能导致20岁前牙齿脱落。虽然一般牙周炎的病因尚不清楚，但革兰氏阴性杆菌伴放线聚集杆菌（原名伴放线放线杆菌）的一个特定克隆（JP2）被认为是生活在非洲北部和西部或来自这些地区的青少年侵袭性牙周炎的可能病因，该疾病在这些地区高度流行。我们对青少年进行了一项基于人群的纵向研究，以评估JP2克隆在侵袭性牙周炎发病中的作用。
共有700名来自摩洛哥拉巴特公立学校的青少年参与了这项研究。我们使用聚合酶链反应（PCR）检测菌斑样本（取自磨牙和切牙部位）中的伴放线放线杆菌，并区分该细菌的JP2克隆和其他非JP2基因型。发现18名个体已经患有牙周炎，将其排除。根据基线时伴放线放线杆菌携带状态，将682名牙周健康的青少年（平均年龄12.5岁；标准差1.0）进行分类。2年后，428名（62.8%）个体返回进行复查，复查包括记录从牙骨质-釉质界到所有现存牙齿牙周袋底部测量的牙周附着丧失情况。
单独携带伴放线放线杆菌JP2克隆的个体（相对风险18.0；95%置信区间7.8 - 41.2，p<0.0001）或同时携带伴放线放线杆菌JP2克隆和非JP2克隆的个体（12.4；5.2 - 29.9，p<0.0001）发生牙周附着丧失的风险显著增加。仅携带非JP2克隆的个体疾病风险增加程度要小得多（3.0；1.3 - 7.1，p = 0.012）。
伴放线放线杆菌的JP2克隆可能是儿童和青少年牙周附着丧失发病的重要病因。伴放线放线杆菌非JP2克隆的共存降低了牙周炎发展的风险，提示该物种的JP2克隆和非JP2克隆之间存在生态位竞争。
