牙周炎及胃病患者牙菌斑中的幽门螺杆菌

目的 明确牙周炎及胃病患者的牙菌斑中是否存在幽门螺杆菌（Ｈｐ）及Ｈｐ是否为细胞毒素相关基因Ａ阳性。方法 利用尿素酶Ｃ基因和ｃａｇＡ设计引物，通过聚合酶链反应（ＰＣＲ）检测口腔中的Ｈｐ。选择１３例胃病及１０例牙周炎患者，每例患者选６个有牙龈炎症的牙位取龈上、龈下菌斑，共计２７６份样本用于ＰＣＲ检测。结果 胃病组１１例患者和牙周炎组全部病例均少有１份菌斑样本检出Ｈｐ，其中尿素酶Ｃ基因在胃病组的阳性率为

Helicobacter pylori in dental plaque of periodontitis and gastric disease patients

Objective To investigate whether Helicobacter pylori (Hp) is a habitant in the oral cavity. Methods A polymerase chain reaction (PCR) assay with oligonucleotide primers homologous to a portion of the urease C and cytotoxin associated gene A (cag A) of Hp was used to test for the presence of Hp in dental plaque. This assay was able to detect the expected 294 bp and 400 bp DNA fragments from as few as 100 Hp cells per reaction. Thirteen gastric disease patients (Group G) and 10 periodontitis patients (Group P) were recruited. A total of 276 supra and subgingival plaque samples were collected, from 6 teeth in each subject for PCR assay. Clinical periodontal parameters including probing depth (PD), bleeding index (BI) and plaque index (PLI) of the sampled sites were recorded. Results In Group G, 11 of 13 patients had at least one Hp positive plaque sample. 28.8% of the tested samples were urease C gene positive and 3.2% were positive for both urease C and cag A genes. All the 10 patients in Group P had at least one Hp positive plaque sample. 49.2% of the tested samples were urease C gene positive and 3.3% were positive for both of the Hp genes. The prevalence of Hp was positively correlated with probing depth and bleeding index at the sampled sites. Conclusion These results suggest that oral cavity is an ecological niche of Hp.