不同种类金属烤瓷底冠与基牙龈沟液的变化

背景：目前关于非贵金属烤瓷和贵金属烤瓷对牙龈、牙周组织健康影响的研究较多,纯钛与非贵金属、贵金属之间进行比较的研究较少。 目的：观察不同种类烤瓷金属材料修复后基牙龈沟液中龈沟液分泌量以及肿瘤坏死因子α和白细胞介素6水平的变化。 方法：选择后牙区(前磨牙和磨牙)患者60例,共80颗受试牙,按烤瓷金属内冠材料不同分为3组,钴铬合金组28颗、纯钛烤瓷组32颗、金铂合金烤瓷组30颗。在修复1,3个月后检测龈沟液的分泌量以及肿瘤坏死因子α和白细胞介素6水平。 结果与结论：修复后1,3个月钴铬合金组龈沟液分泌量以及肿瘤坏死因子α和白细胞介素6水平明显高于修复前(P < 0.05)。修复后1,3个月纯钛组的龈沟液分泌量,肿瘤坏死因子α水平高于修复前(P < 0.05),而白细胞介素6水平与修复前比较差异无显著性意义(P > 0.05)。修复后1,3个月金铂合金组的各项指标与修复前比较差异无显著性意义(P > 0.05)。钴铬合金组龈沟液分泌量、肿瘤坏死因子α和白细胞介素6水平高于纯钛组、金铂合金组(P < 0.05)。纯钛组龈沟液分泌量、肿瘤坏死因子α水平高于金铂合金组(P < 0.05)。     

金铂合金烤瓷冠对牙周组织的影响

背景：金属烤瓷冠的修复材料种类很多,每种材料的性能及对牙周组织细胞毒性影响均不相同。 目的：观察金铂合金烤瓷冠修复后对牙周组织的影响。 方法：选择2009-06/2010-01采用金铂合金烤瓷冠进行上颌切牙修复患者21例(26颗牙),以患牙对侧的同名健康牙为对照牙。烤瓷冠戴入6~8个月后复诊。 结果与结论：修复体边缘的深度及密合度均符合临床要求,修复后患牙的菌斑指数和龈沟液内血管内皮生长因子、肿瘤坏死因子α水平与对照牙比较,差异无显著性意义(P > 0.05),但患牙探诊深度、龈沟内出血指数及龈沟液量明显高于对照牙,差异有显著性意义(P < 0.05)。说明金铂合金烤瓷冠对患牙牙周组织有一定的不良影响。     

非贵金属材料钴铬合金烤瓷联冠及烤瓷桥修复后基牙咬合力与牙周组织的变化北大核心

背景:测量牙缺失患者修复后的咬合力指标,可有效判断修复效果和患者修复后口腔功能的恢复情况。目的:观察行钴铬合金烤瓷联冠、烤瓷桥修复后患者基牙咬合力及牙周组织的变化。方法:将100例男性烤瓷牙修复患者随机分5组修复,其中20例采用钴铬合金烤瓷联冠修复前牙,20例采用钴铬合金烤瓷联冠修复前磨牙,20例采用钴铬合金烤瓷联冠修复磨牙,20例采用钴铬合金烤瓷桥修复前牙,20例采用钴铬合金烤瓷桥修复后牙。修复前、修复后即刻、修复后6个月,检测基牙咬合力变化及牙周相关指标变化。结果与结论:(1)咬合力:5组修复后即刻、修复后6个月的咬合力均高于修复前(P<0.05);修复前、修复后即刻、修复后6个月,烤瓷联冠磨牙组、烤瓷桥后牙组的咬合力高于烤瓷联冠前磨牙组、烤瓷联冠前牙组、烤瓷桥前牙组(P<0.05),烤瓷联冠前磨牙组咬合力高于烤瓷联冠前牙组、烤瓷桥前牙组(P<0.05);(2)牙周组织:5组组内修复前后的牙周袋探诊深度、菌斑控制指数、临床附着水平、牙龈沟液量比较差异均无显著性意义(P>0.05);5组间各指标比较差异均无显著性意义;(3)结果表明:行钴铬合金烤瓷联冠、烤瓷桥修复治疗能显著提升患者基牙咬合力,并且对牙周影响很小,生物相容性较好。     

不同材料烤瓷冠在后牙种植修复中的对比

背景：种植体上部结构牙冠材料的选择十分重要,其临床修复效果直接影响到种植体的寿命和患者的牙周健康状况。 目的：比较Lava氧化锆全瓷、金铂合金烤瓷与银钯合金烤瓷冠在后牙单颗缺失口腔种植修复中的临床效果。 方法：选择60例120颗第一磨牙缺失病例,完成单颗牙缺失种植牙修复治疗,上部结构修复牙冠材料分别为Lava氧化锆全瓷冠、金铂合金烤瓷冠与银钯合金烤瓷冠,每种材料40颗,比较3种修复体的临床修复效果。 结果与结论：通过6-48个月的随访发现,Lava氧化锆全瓷冠组和金铂合金烤瓷冠组的牙龈边缘着色、龈缘密合度、修复体颜色优于银钯合金烤瓷冠组,Lava氧化锆全瓷冠组的牙龈边缘着色和修复体颜色优于金铂合金烤瓷冠组,金铂合金烤瓷冠组的龈缘密合度优于Lava氧化锆全瓷冠组;银钯合金烤瓷冠抗折程度最强,最具临床优越性,但其牙龈指数最高,牙龈健康程度最差,菌斑形成速度最快、程度最重。由此可见,在种植修复完成后需要选择较为适合的冠部修复体进行种植修复,Lava氧化锆全瓷冠具有卓越的生物相容性,而金铂合金烤瓷冠在边缘密合性方面更具优势,此两种修复体在临床治疗中具有一定的优势。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

CAD/CAM氧化锆全瓷冠修复对牙周组织的影响

背景：全冠修复体远期疗效的维持很大程度上取决于牙周组织的健康状况。 目的：探讨CAD/CAM氧化锆全瓷冠修复体对牙周组织健康状况的影响。 方法：随机选择需行全冠修复的55例患者64颗基牙作为研究对象,实验组为CAD/CAM氧化锆全瓷冠修复的29例患者32颗基牙,对照组为进行镍铬合金烤瓷冠修复的26例患者32颗基牙。检测两组修复前和修复后12个月的龈沟液含量、肿瘤坏死因子α和白细胞介素6水平,以及牙龈出血指数、牙周探诊深度、菌斑指数及附着丧失。 结果与结论：实验组修复前后各指标比较差异均无显著性意义(P > 0.05)。对照组修复12个月后的龈沟液含量、肿瘤坏死因子α、白细胞介素6、牙龈出血指数、牙周探诊深度及菌斑指数均高于修复前(P > 0.05)。修复12个月后,实验组龈沟液含量、肿瘤坏死因子α、白细胞介素6、牙龈出血指数、牙周探诊深度及菌斑指数均低于对照组(P < 0.05)。表明CAD/CAM氧化锆全瓷冠修复后对牙周组织健康基本无不良影响。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

不同烤瓷材料对牙冠损伤的修复效果及修复的满意度评价

目的探讨不同烤瓷材料对牙冠损伤的修复作用及对修复的满意度评价。方法选择解放军第三二三医院2012年5月至2015年5月收治的128例牙冠损伤患者,其中男性71例,女性57例;年龄24~60岁。根据修复方法不同分为钴铬合金烤瓷冠修复组与全瓷冠修复组,每组64例。分别进行钴铬合金烤瓷冠修复与全瓷冠修复,治疗6个月,观察两组患者对修复的牙体满意度、牙体颜色逼真率、正常咀嚼率、牙周正常率和邻接良好率及不良反应发生情况。结果全瓷冠修复组优良率(96.9%)比钴铬合金烤瓷冠修复组(79.7%)高,差异有统计学意义(χ~2=6.528,P0.05)。全瓷冠修复组牙体颜色逼真率、正常咀嚼率、牙周正常率和邻接良好率明显优于钴铬合金烤瓷冠修复组,差异有统计学意义(P0.05)。全瓷冠修复组不良反应发生率(6.25%)明显低于钴铬合金烤瓷冠修复组(45.3%),差异有统计学意义(χ~2=10.648,P0.05)。全瓷冠修复组满意度为96.9%,明显高于钴铬合金烤瓷冠修复组(79.7%),差异有统计学意义(χ~2=6.528,P0.05)。结论采用全瓷冠对患者牙齿缺损进行修复,患者牙齿美观度高,术后不良反应率低,患者术后随访满意度高。     

金属烤瓷修复体对牙龈组织影响的临床初步分析与研究

目的研究比较镍铬合金、钛合金、金合金为内冠的金属烤瓷修复体引起牙龈炎症的情况.方法对于上前牙分别用镍铬合金、钛合金、金合金为内冠各50例进行金属烤瓷修复,观察修复后有无牙龈充血、水肿、增生、退缩、牙周袋、颈缘色素沉着情况(颈缘黑线).结果镍铬合金为内冠的金属烤瓷冠修复后有20例引起牙龈炎或出现龈缘色素沉着.钛合金为内冠的烤瓷冠修复后有3例出现牙龈炎或出现色素沉着.金合金为内冠的金属烤瓷冠修复后只有1例引起牙龈炎.结论金合金为内冠的金属烤瓷冠修复体对牙龈组织无不良影响,镍铬合金烤瓷冠修复体易引起牙龈炎及牙颈缘黑色,钛合金烤瓷修复体不易引起牙龈炎,但也可以起牙颈缘黑线.     

四种烤瓷冠基底金属浸提液干预人牙龈成纤维细胞尿纤溶酶原激活剂和Ⅰ型纤溶酶原激活物抑制剂的表达

背景：修复材料的生物相容性是决定临床修复效果的重要因素之一。 目的：通过比较4种金属浸提液对人牙龈成纤维细胞尿纤溶酶原激活剂和Ⅰ型纤溶酶原激活物抑制剂表达的差异探索其生物相容性。 方法：选用活体牙龈,原代培养人牙龈成纤维细胞,采用镍铬、钴铬、纯钛及金钯合金4种金属浸提液进行干预,以未进行干预的细胞作为对照。 结果与结论：ELISA检测结果显示镍铬和钴铬合金浸提液干预后细胞尿纤溶酶原激活剂表达增加;免疫荧光实验结合电镜观察发现镍铬和钴铬合金浸提液干预的细胞胞质荧光染色深,分布均匀,遍布整个细胞,提示细胞Ⅰ型纤溶酶原激活物抑制剂表达增加。而纯钛和金钯合金浸提液对细胞尿纤溶酶原激活剂和Ⅰ型纤溶酶原激活物抑制剂的表达无影响。说明纯钛和金钯合金的生物相容性优于镍铬和钴铬合金。      

不同后牙固定桥材料的临床应用

背景：在后牙固定桥材料的选择上尚存争议,氧化锆全瓷冠、金铂合金烤瓷冠与镍铬合金烤瓷冠各具优点与不足。 目的：比较Lava氧化锆全瓷、金铂合金烤瓷与镍铬合金烤瓷后牙固定桥辅以纤维桩、树脂核修复后牙牙列缺损的临床效果。 方法：选择120例下颌第一磨牙缺失患者,分别应用Lava氧化锆全瓷后牙固定桥、金铂合金烤瓷与镍铬合金烤瓷后牙固定桥并辅以纤维桩、树脂核修复后牙牙列缺损,比较3种修复体的修复效果。 结果与结论：通过6-48个月的随访发现,在牙龈边缘着色、龈缘密合度、修复体颜色、修复体周围龋方面Lava氧化锆全瓷冠和金铂合金烤瓷冠的修复效果优于镍铬合金烤瓷冠,其中Lava氧化锆全瓷冠的牙龈边缘着色和修复体颜色优于金铂合金烤瓷冠,而金铂合金烤瓷冠的龈缘密合度好于Lava氧化锆全瓷冠。在修复体折裂程度方面镍铬合金烤瓷冠低于Lava氧化锆全瓷冠和金铂合金烤瓷冠,但镍铬合金烤瓷修复者牙龈指数和基牙松动程度最高,牙龈健康程度最差,Lava氧化锆全瓷冠和金铂合金烤瓷冠比较以上指标差异无显著性意义。由此可见,在后牙固定桥修复体种类的选择上,Lava氧化锆全瓷冠和金铂合金烤瓷冠是较为理想的修复体;前者在生物相容性方面具有一定的优越性,而后者在边缘密合性方面更具优势。     

IPS e.max Press全瓷冠用于前牙修复：边缘适合度及颜色匹配随访

背景：IPS e.max Press热压铸全瓷以其较好的美观效果和生物学性能已被越来越多地应用于临床修复。 目的：分析IPS e.max Press全瓷冠用于前牙美学修复的边缘适合度及颜色匹配等情况。 方法：纳入前牙美容修复患者52例(138颗牙),其中男20例,女32例,年龄18-45岁,前牙缺损62颗,牙外伤46颗,畸形小牙30颗,分为2组修复,治疗组(n=26)采用IPS e. max Press全瓷冠和传统钴铬合金烤瓷冠修复,对照组(n=26)采用传统钴铬合金烤瓷冠修复,修复后1周复诊,调查患者满意度;修复后随访6个月、2年,评估修复体完整性、边缘适合度、牙龈健康状况及颜色匹配等情况。 结果与结论：修复后1周,治疗组患者对修复体颜色、外形及舒适度方面的满意度显著高于对照组(P < 0.05);治疗后6个月,治疗组边缘适合度、牙龈健康状况及颜色匹配显著优于对照组(P < 0.05);治疗后2年,治疗组边缘适合度、牙龈健康状况及颜色匹配显著优于对照组(P < 0.05)。表明IPS e.max Press全瓷冠修复前牙具有良好的边缘适合度、牙龈健康状况及颜色匹配等生物学特性,患者满意度高。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Etiological analysis of initial colonization of periodontal pathogens in oral cavity

It is unclear when the initial colonization by periodontal pathogens occurs in the oral cavity. Therefore, we report here the association between specific age groups and the time when the initial colonization by periodontal pathogens occurs in the oral cavity in such groups. Findings are based on an epidemiological analysis of the prevalence of five periodontal pathogens in the oral cavities of a wide range of age populations, from newborn to elderly, who were randomly selected in a geographic region of Brazil. These periodontal pathogens include Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Tannerella forsythia and were analyzed in the bacterial samples isolated from gingival sulcus, the dorsum of the tongue, and cheek mucosa of diverse age groups, using a bacterial DNA-specific PCR method. Results indicated that there are distinct age-related groups where initial colonization by the five periodontal pathogens examined in this study can be detected and that the presence of teeth is a permissive factor for colonization by P. gingivalis, P. intermedia, and T. forsythia. Although it remains unclear exactly how or when target pathogens colonize healthy subjects, an understanding of age-related groups does provide a potentially useful tool in the early detection and prevention of periodontitis in healthy individuals.     

Association of three bacterial species and periodontal status in Chinese adults: an epidemiological approach

Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia are oral pathogens associated with periodontitis. The association between these three bacteria and periodontal disease has been reported in populations of many countries. However, corresponding data in Chinese populations are still lacking. The aim of this study was to detect these pathogens in subgingival plaque collected from 468 subjects with chronic periodontitis in a group of Chinese adults by using a PCR method and to determine the degree of association between the target bacteria and periodontal status based on logistic regression analysis. A. actinomycetemcomitans, P. gingivalis, and T. forsythia were found in 20.5%, 70.7%, and 77.1% of the subjects, respectively. About one-third (36.1%) of subjects had chronic periodontitis. Upon univariate analysis, age, male gender, current smoking status, diabetes, and the presence of A. actinomycetemcomitans or P. gingivalis were positively associated with chronic periodontitis, whereas education and income exhibited inverse associations with chronic periodontitis. Upon multivariate analysis, education, current smoking status, diabetes, and the presence of A. actinomycetemcomitans and P. gingivalis remained significant. The adjusted odds ratios for having chronic periodontitis were 2.5 and 3.4 in subjects positive for A. actinomycetemcomitans and P. gingivalis, respectively. However, no significant association was observed between the presence of T. forsythia and periodontal status. This study assesses the prevalence of periodontal pathogens and chronic periodontitis and the associations with sociodemographic characteristics among this group of Chinese adults. These findings also suggest that PCR should be considered for field oral epidemiologic studies and may be necessary in investigations presenting major logistic challenges.     

Immunoglobulin G response to subgingival gram-negative bacteria in human subjects

Serum and gingival crevicular fluid from normal healthy adults and patients with periodontitis were screened for immunoglobulin G antibodies to antigens from Bacteroides gingivalis 381, Bacteroides intermedius 24, Bacteroides loescheii ATCC 15930, Fusobacterium nucleatum ATCC 25586, Eikenella corrodens 1073, Actinobacillus actinomycetemcomitans ATCC 29522, and Capnocytophaga sp. strain M-12. Immunoglobulin G antibody titers to the antigens were measured by an enzyme-linked immunosorbent assay. The antibody levels to B. gingivalis in serum and gingival crevicular fluid were significantly higher in the samples from patients with periodontitis than in samples from healthy individuals. Although there were individual differences within patient groups, a positive correlation (P less than 0.01) was found between the serum immunoglobulin G levels to B. gingivalis and the development of periodontitis. The antibodies to F. nucleatum (P less than 0.05), E. corrodens (P less than 0.05), and A. actinomycetemcomitans were slightly higher in patients with periodontitis than in normal subjects. There were no remarkable differences between the two groups in titers to B. intermedius, B. loescheii, and Capnocytophaga sp.     

Periodontitis vaccine decreases local prostaglandin E2 levels in a primate model

Interleukin-1beta, tumor necrosis factor alpha, prostaglandin E2 (PGE2), and Porphyromonas gingivalis-specific immunoglobulin G levels in gingival crevicular fluid were measured in primates immunized with a P. gingivalis vaccine followed by ligature-induced periodontitis. Only PGE2 levels were dramatically suppressed (P < 0.0001) in immunized animals versus controls. A significant correlation (P < 0.027) was also found between PGE2 levels and decreased bone loss scores. This study presents the first evidence of a potential mechanism involved in periodontitis vaccine-induced suppression of bone loss in a nonhuman primate model and offers insight into the role of PGE2 in periodontal destruction.     

DNA from periodontopathogenic bacteria is immunostimulatory for mouse and human immune cells

Although bacterial DNA (bDNA) containing unmethylated CpG motifs stimulates innate immune cells through Toll-like receptor 9 (TLR-9), its precise role in the pathophysiology of diseases is still equivocal. Here we examined the immunostimulatory effects of DNA extracted from periodontopathogenic bacteria. A major role in the etiology of periodontal diseases has been attributed to Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Peptostreptococcus micros. We therefore isolated DNA from these bacteria and stimulated murine macrophages and human gingival fibroblasts (HGF) in vitro. Furthermore, HEK 293 cells transfected with human TLR-9 were also stimulated with these DNA preparations. We observed that DNA from these pathogens stimulates macrophages and gingival fibroblasts to produce tumor necrosis factor alpha and interleukin-6 in a dose-dependent manner. Methylation of the CpG motifs abolished the observed effects. Activation of HEK 293 cells expressing TLR-9 which were responsive to bDNA but not to lipopolysaccharide confirmed that immunostimulation was achieved by bDNA. In addition, the examined bDNA differed in the ability to stimulate murine macrophages, HGF, and TLR-9-transfected cells. DNA from A. actinomycetemcomitans elicited a potent cytokine response, while DNA from P. gingivalis and P. micros showed lower immunostimulatory activity. Taken together, the results strongly suggest that DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros possesses immunostimulatory properties in regard to cytokine secretion by macrophages and fibroblasts. These stimulatory effects are due to unmethylated CpG motifs within bDNA and differ between distinct periodontopathogenic bacteria strains. Hence, immunostimulation by DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros could contribute to the pathogenesis of periodontal diseases.     

Prevalence of periodontal pathogens in dental plaque of children

Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Tannerella forsythensis have been implicated as the main etiological agents of periodontal disease. The purpose of this work was to estimate the prevalence of these organisms in plaque from children without gingivitis (group 1; n = 65) and from those with gingivitis (group 2; n = 53). Extracted DNA from plaque was subjected to two rounds of PCR targeting the 16S rRNA gene using both universal primers and species-specific primers. The results were as follows: group 1, P. gingivalis, 49%; A. actinomycetemcomitans, 55%; and T. forsythensis, 65%; group 2, P. gingivalis, 47%; A. actinomycetemcomitans, 59%; and T. forsythensis, 45%. T. forsythensis was detected more frequently in children with no gingivitis than in those with gingivitis (P = 0.03). There was no significant difference between the two groups with respect to the presence of P. gingivalis or A. actinomycetemcomitans in either group (P > 0.05). Logistic regression analysis revealed that the odds of a patient having gingivitis were 2.3 times greater in the absence of T. forsythensis. In conclusion, the results of this study have shown that the three pathogens can be detected in the dental plaque of healthy children and of those with gingivitis and that T. forsythensis is associated with dental plaque at sites with no gingivitis.     

Modification of cystatin C activity by bacterial proteinases and neutrophil elastase in periodontitis.

AIM: To study the interaction between the human cysteine proteinase inhibitor, cystatin C, and proteinases of periodontitis associated bacteria. METHODS: Gingival crevicular fluid samples were collected from discrete periodontitis sites and their cystatin C content was estimated by enzyme linked immunosorbent assay (ELISA). The interaction between cystatin C and proteolytic enzymes from cultured strains of the gingival bacteria Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans was studied by measuring inhibition of enzyme activity against peptidyl substrates, by detection of break down patterns of solid phase coupled and soluble cystatin C, and by N-terminal sequence analysis of cystatin C products resulting from the interactions. RESULTS: Gingival crevicular fluid contained cystatin C at a concentration of approximately 15 nM. Cystatin C did not inhibit the principal thiol stimulated proteinase activity of P gingivalis. Instead, strains of P gingivalis and P intermedia, but not A actinomycetemcomitans, released cystatin C modifying proteinases. Extracts of five P gingivalis and five P intermedia strains all hydrolysed bonds in the N-terminal region of cystatin C at physiological pH values. The modified cystatin C resulting from incubation with one P gingivalis strain was isolated and found to lack the eight most N-terminal residues. The affinity of the modified inhibitor for cathepsin B was 20-fold lower (Ki 5 nM) than that of full length cystatin C. A 50 kDa thiol stimulated proteinase, gingipain R, was isolated from P gingivalis and shown to be responsible for the Arg8-bond hydrolysis in cystatin C. The cathepsin B inhibitory activity of cystatin C incubated with gingival crevicular fluid was rapidly abolished after Val10-bond cleavage by elastase from exudate neutrophils, but cleavage at the gingipain specific Arg8-bond was also demonstrated. CONCLUSIONS: The physiological control of cathepsin B activity is impeded in periodontitis, owing to the release of proteinases from infecting P gingivalis and neutrophils, with a contribution to the tissue destruction seen in periodontitis as a probable consequence.     

Epithelial cell response to challenge of bacterial lipoteichoic acids and lipopolysaccharides in vitro

Accumulating dental plaque at the gingival margin contains lipoteichoic acids (LTAs) from the cell walls of gram-positive bacteria. In subgingival plaque associated with periodontal disease the amount of lipopolysaccharides (LPSs) from gram-negative bacteria increases. As the gingival junctional epithelium (JE) is an important structural and functional tissue, participating in the first line defence against apical advancement of dental plaque, this study examined the direct effects of LTAs (from Streptococcus mutans and S. sanguis) and LPSs (from Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Escherichia coli) on two epithelial cell lines (HaCaT and ERM) and a culture model for human JE. The cells were exposed to the LTAs or LPSs (10-50 microg/ml) for variable periods of time. None of the bacterial surface components had any effect on primary adhesion or on the epithelial attachment of the JE cultures. However, cell growth and mitotic activity were consistently reduced in all cultures treated with LTAs. In contrast, LPSs showed only slight or no effects on cell growth and mitotic activity depending on the epithelial cells used. This suggests that LPSs, despite their established role as modulators of inflammation, do not have direct harmful effects - at the concentrations found in dental plaque and gingival crevicular fluid - which would explain the mechanism of epithelial degeneration and detachment from the tooth surface. However, the LTAs appear to inhibit the renewal of epithelium and may thus contribute to degeneration of coronal JE and subgingival colonisation by periodontal pathogens.     

牙周致病菌在动脉粥样硬化斑块中的检测

目的 检测冠状动脉粥样硬化斑块中的5种特异性牙周致病菌.方法 收集101例行冠状动脉搭桥手术患者的动脉粥样硬化斑块标本,采用Chelex-100法提取冠状动脉粥样硬化斑块中的DNA,并通过PCR分别检测动脉粥样硬化斑块中的牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)、伴放线放线杆菌(Actinobacillus actinomycetemcomitans,Aa)、具核梭杆菌(Fusobacterium nucleatum,Fn)、中间普氏菌(Prevotella intermedia,Pi)、福赛斯坦纳菌(Tannerella forsythensis,Tf)5种牙周特异性致病菌.结果 101例患者动脉粥样硬化斑块中牙龈卟啉单胞菌(Pg)的检出率为31％,福赛斯坦纳菌(Tf)为42％,中间普氏菌(Pi)为26％,具核梭杆菌(Fn)为21％,伴放线放线杆菌(Aa)为23％.这几种细菌的PCR产物通过测序,结果与GenBank数据库中的序列进行比对同源性达99％～100％.结论 牙周致病菌在冠心病的发生、发展中可能发挥着一定作用,考虑慢性牙周炎与冠心病之间有一定的相关性.