The predominant cultivable microbiota of active and inactive lesions of destructive periodontal diseases

Subgingival plaque samples were taken from active and inactive lesions in 33 subjects exhibiting active destructive periodontal diseases. Active diseased sites were those which showed a significant loss of attachment within a 2-month interval as computed by the "tolerance method". The predominant cultivable species from 100 active sites were compared with those found in 150 inactive sites of comparable pocket depth and attachment level loss. Among the 33 subjects, W. recta, B. intermedius, F. nucleatum, B. gingivalis and B. forsythus were elevated more often in active sites; whereas, S. mitis, C. ochracea, S. sanguis II, V. parvula and an unnamed Actinomyces sp. were elevated in inactive sites. The likelihood of a site being active was increased if B. forsythus, B. gingivalis, P. micros, A. actinomycetemcomitans, W. recta, or B. intermedius were detected in that site, and decreased if S. sanguis II, the Actinomyces sp., or C. ochracea were detected.     

The microflora of periodontal sites showing active destructive progression

20 adult periodontitis (AP) subjects were examined every 2 to 4 months and microbiological samples were collected and cultured when 2 mm or more loss of attachment (active sites) was detected by 2 examiners. Similar sites in which no progressive destruction was observed (control sites) also were sampled in the same subjects. By lambda-analysis, there was no statistically significant difference in floras of active (42 sites from 12 subjects) and control (36 sites from 12 subjects) sites or between the floras of the active and control sites and of 63 samples from 22 AP subjects that were examined previously in a cross-sectional study. By paired t test, no microbial species had a significantly greater association with active than with control sites. The only species that were detected in one or more samples from all subjects with active sites were Wolinella recta, Fusobacterium nucleatum, and Peptostreptococcus micros. Porphyromonas gingivalis and 9 other taxa were isolated from one-half or more of the persons with active sites. The composition of microbiological floras of all periodontitis samples was statistically significantly different from that of subjects with healthy gingiva. The composition of microfloras of sites in subjects with naturally-occurring gingivitis was intermediate between that of subjects with healthy gingiva and that of active and control sites in AP subjects.     

Predominant microflora of severe, moderate and minimal periodontal lesions in young adults with rapidly progressive periodontitis

The purpose of this investigation was to study the microflora of severe, moderate and minimal periodontal lesions, in young adults with rapidly progressive periodontitis (RPP). Subgingival plaque samples were taken from 142 periodontal lesions in 10 young adults aging 25 to 35 years. The examination of the subgingival microflora indicated that certain species, including Porphyromonas gingivalis, Bacteroides forsythus, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans , and Campylobacter species were found to be predominant in severe periodontal lesions. B. forsythus, P. gingivalis, Prevotella intermedia, F. nucleatum, Capnocytophaga ochracea , were predominant in medium lesions while Streptococcus species and Actinomyces species, C. ochracea, Haemophilus segnis and Veillonella parvula , were found in higher levels in minimal periodontal lesions.     

Distribution of morphologically different micro-organisms associated with active periodontal lesions

The morphological composition of the subgingival plaque associated with active periodontitis lesions and comparable inactive control lesions were determined in a 36-year-old patient with advanced periodontal disease. Monthly measurements of the clinical attachment level were subjected to linear regression analysis as a function of time. Attachment loss was recorded during the monitoring period at 10 sites, with loss of 2 mm or more at 6 sites. Plaque samples taken from these 6 sites and from 6 control sites with similar clinical conditions were not of uniform composition. Active lesions harboured on average 46% more cocci and twice as many large spirochetes as inactive control lesions. A linear regression analysis of the proportions of different morphotypes in the subgingival plaque versus the calculated monthly attachment loss rate at the time of sampling provided only very weak correlations, if at all. The observations made in the patient under investigation suggest that there is no great probability of suspected differences in the floras of active and inactive lesions being detected by dark-field analysis alone. The role of motile rods and spirochetes may have been over-rated hitherto.     

Effect of modified Widman flap surgery and systemic tetracycline on the subgingival microbiota of periodontal lesions

33 subjects with evidence of active destructive periodontal disease were treated by modified Widman flap surgery and systemic tetracycline (1 g/day for 21 days). Subgingival plaque samples were taken from 41 sites in 12 of these subjects before and 6 months after therapy for predominant cultivable microbiota studies. Mean pocket depth and attachment levels in the 41 sampled sites were 7.1 +/- 2.9 mm and 7.7 +/- 3.2 mm prior to therapy and 4.8 +/- 2.3 mm and 6.2 +/- 3.4 mm after therapy. B. melaninogenicus and V. parvula were more frequently detected in samples taken after therapy, while S. intermedius, S. morbillorum, S. uberis and W. recta were less frequently detected after therapy. A. actinomycetemcomitans were detected in 7 sites pretherapy and 1 site post therapy. The frequency of detection of B. gingivalis and B. intermedius was virtually unchanged. The mean levels of the Actinomyces sp., A. actinomycetemcomitans, B. gingivalis, B. intermedius, S. morbillorum, S. uberis and W. recta were decreased after therapy, while the mean levels of B. melaninogenicus, S. mitis, S. sanguis II and V. parvula were increased after therapy. V. parvula showed the greatest increase to 8.2% of the microbiota. In the second phase of the study, subgingival plaque samples from 94 sites in the 33 treated subjects were analyzed by predominant cultivable techniques. As a result of therapy, 24 sites exhibited attachment loss greater than 2 mm, 23 sites exhibited "gain" greater than 2 mm and the remaining 47 sites were considered to be unchanging.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intragingival occurrence of Actinobacillus actinomycetemcomitans and Bacteroides gingivalis in active destructive periodontal lesions

A total of six active and six nonactive sites from six untreated periodontitis patients were examined for intragingival presence of Actinobacillus actinomycetemcomitans and Bacteroides gingivalis. The active destructive periodontal disease was determined by the "tolerance method." The method of immunoperoxidase was used in the identification of intragingival microorganisms in active and nonactive periodontal sites. Light microscopic sections of gingival tissues consecutive to those with gram stain, revealing presence of bacteria (substantiated by electron microscopy), were stained with peroxidase-labeled antibodies against A. actinomycetemcomitans and B. gingivalis. B. gingivalis was found to be significantly elevated in the connective tissue of active sites when compared to nonactive sites. A statistically significant border-line difference was found between active and nonactive sites in the connective tissue invaded by A. actinomycetemcomitans. Our findings plus the well established periodontopathic potential of A. actinomycetemcomitans and B. gingivalis support the concept that these bacteria are important invasive pathogenic agents in periodontitis.     

Immunohistological characteristics of periodontal lesions associated with Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans infections

In this study, various phenotypes of infiltrating cells in the periodontium adjacent to pockets harboring Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were evaluated. Furthermore, the pattern of Class II antigen expression in the periodontal tissues was determined. Eight lesions were associated with the presence of P. gingivalis and 12 with A. actinomycetemcomitans. Predominant cells in the inflammatory infiltrate were T- and B-cells. In most biopsies T-cells dominated over B-cells. The proportion of P. gingivalis , but not of A. actinomycetemcomitans , was positively correlated to the total number of infiltrating cells in the tissue. A. actinomycetemcomitans sites demonstrated somewhat lower proportions of CD3+, CD4+ and CD19+ cells than P. gingivalis sites. However, the tendency of decreasing CD4+/CD8+ ratio with increasing number of A. actinomycetemcomitans indicates a local imbalance in immunoregulation. The frequency of class II antigen expression of both mononuclear and epithelial cells, a sign of immunological activation, was generally high.     

牙周治疗在牙周-牙髓联合病变中的应用效果评价

目的 评价牙周治疗在牙周-牙髓联合病变中的疗效。方法 选择109例牙周-牙髓病变患者（120颗患牙）,所有患牙均经完善的根管治疗,分为A、B 2组。A组为牙周治疗组（60颗患牙）,根管治疗完成2周后行牙周基础治疗;6周后仍有5 mm以上牙周袋且探诊后出血者,进行翻瓣术治疗。B组为非牙周治疗组（60颗患牙）,单纯行根管治疗和龈上洁治术。术后3、6、12、24个月进行随访,观察2组患者牙周探诊深度（PD）、牙槽骨吸收程度、牙松动度（TM）等的变化。采用SPSS 22.0软件包对数据进行统计学分析。结果 A组术前、术后2年PD分别为（5.966±1.877）mm、（5.133±1.935)mm,牙周探诊深度减轻,有统计学差异。B组术前、术后2年PD分别为（5.533±1.856）mm、( 6.167±1.927)mm,牙周探诊深度显著增加。2组术前TM无统计学差异（P>0.05）。术后2年,A组TM显著低于B组（P<0.05）。X线表现,A组术后2年牙槽骨吸收较术前无显著变化（P>0.05）;B组术后2年,牙槽骨吸收较术前显著减轻（P<0.05）。结论 根管治疗结合牙周治疗用于牙周-牙髓联合病变能取得较好的疗效,值得推广应用。     

Specific infections as the etiology of destructive periodontal disease: a systematic review

Destructive periodontal disease has been primarily defined and investigated as an infectious disease. The aim of this study was to systematically search for cohort studies where microbiological diagnoses were performed before the onset of destructive periodontal disease and where statistically significant associations were identified. A search was executed in PubMed. The results showed that three studies published after 2005 supported the infection hypothesis for one putative periodontal pathogen: Aggregatibacter actinomycetemcomitans. These three studies were conducted in predominantly non‐Caucasian pediatric populations living in geographic areas with an elevated child‐mortality rate. These studies did not obtain physical or laboratory markers of health, making it possible that A. actinomycetemcomitans was not a cause but a marker for poor environmental or systemic health. No cohort studies were identified supporting the infection hypothesis in adults, Caucasians or in a population residing in areas with child‐mortality rates reflective of healthy population goals. While the possibility cannot be excluded that A. actinomycetemcomitans has an etiological role in certain specific pediatric populations, there are no cohort studies supporting an infectious etiology of destructive periodontal disease in adults.     

Er∶YAG激光治疗Ⅱ度根分叉病变牙周炎患者的临床疗效评价

目的 观察并评价Er:YAG（Erbium-doped yttrium aluminium garnet lase, 掺铒钇铝石榴石）激光治疗Ⅱ度根分叉病变牙周炎患者的临床疗效。方法 纳入30例慢性牙周炎出现Ⅱ度根分叉病变患者（60颗患牙）,采取左右半口对照研究。以超声龈上洁治1周后作为基线,随机分为实验组：超声波及手用器械行龈下刮治、根面平整+Er:YAG激光牙周袋内照射,对照组：单纯使用超声波及手用器械行龈下刮治、根面平整治疗对侧同名牙。治疗后12周、20周后比较2组牙龈指数（gingival index, GI）、牙周袋深度（pocket depth, PD）、水平探诊深度 (horizontal probing depth, HPD)、附着丧失 (attachment loss, AL)的变化。采用 SPSS 20.0软件包进行统计学处理。结果 实验组和对照组各牙周临床指标（GI、PD、HPD、AL）在治疗后12周、20周与基线时相比,均显著下降（P<0.05）。治疗后12周和20周,实验组PD分别为 (4.03±0.48) 和 (3.43±0.45) mm,对照组为 (4.82±0.55) 和 (4.27±0.36) mm。经配对样本t检验,实验组PD减小量显著高于对照组（P<0.05）。治疗后12周,2组间HPD无显著差异;术后20周复查HPD发现,实验组为 （3.01±0.34） mm,对照组为（3.78±0.29） mm,实验组HPD降低但仍显著大于对照组（P<0.05）。12周和20周时,实验组GI和AL值较对照组低,但差异无统计学意义。结论 Er:YAG激光对慢性牙周炎Ⅱ度根分叉患者的治疗安全有效,临床应用价值显著。     

Antimicrobial photodynamic active biomaterials for periodontal regeneration

Objective

Biomaterials for periodontal regeneration may have insufficient mechanical and antimicrobial properties or are difficult to apply under clinical conditions. The aim of the present study was to develop a polymeric bone grafting material of suitable physical appearance and antimicrobial photodynamic activity.

糖尿病大鼠牙周组织中免疫调节相关信号通路研究

目的观察糖尿病大鼠模型牙周组织中CD4、CD8、核因子-κB受体活化子配体(receptor activator forNF-κB ligand,RANKL)及骨保护素(osteoprotegerin,OPG)表达的变化。方法 38只健康雄性SD大鼠,随机选取30只,高热量饲料喂养1个月后,建立肥胖模型,随后每只大鼠按55 mg/kg一次性静脉注射链脲佐菌素(strepto-zotocin,STZ),建立糖尿病模型组;其余8只普通饲料喂养1个月后,一次性静脉注射相同剂量的pH值4.5、0.1 mol/L柠檬酸缓冲液,设为对照组。建模第16周处死大鼠,解剖上颌骨,制作3μm厚连续切片,荧光免疫组化检测牙周组织中CD4、CD8及RANKL、OPG的表达。采用激光扫描共聚焦显微镜(laser scanning confocal micro-scope,LSCM)采集图像,行灰度值分析,比较CD4、CD8、RANKL、OPG在糖尿病组和对照组大鼠牙周组织中的表达差异。结果糖尿病组CD4、CD8、RANKL的表达均高于对照组,差异有统计学意义(P<0.05);糖尿病组与对照组相比OPG表达降低,差异无统计学意义。结论糖尿病可能通过RANKL/OPG调节途径促进牙周炎的发生发展。     

Prevalence and risk indicators for destructive periodontal diseases in 3 urban American minority populations

BACKGROUND, AIMS: Destructive periodontal diseases have been reported disproportionately more prevalent and severe in African-Americans relative to other American populations. Differences in subgingival microbiota and host immune response have also been reported for African-Americans, implying that risk factors for disease progression may also differ for these populations. Since it is not clear whether these differences are truly genetic or due to confounding variables such as social economic status, we examined a series of clinical, environmental, demographic, and microbiologic features associated with periodontal disease status in a group of 185 urban minority subjects resident within the greater New York metropolitan area. METHODS: The study population consisted of 56 Asian-American, 71 African-American and 58 Hispanic subjects. Clinical data recorded included pocket depth, attachment level, gingival erythema, bleeding upon probing, suppuration, and the presence of supragingival plaque. Environmental and demographic data recorded included smoking history, years resident in the United States, whether the subject reported a private dentist and occupational status. Subgingival plaque was sampled from the mesial aspect of all teeth exclusive of third molars and the levels of 40 subgingival species enumerated using checkerboard DNA-DNA hybridization. RESULTS: The African-American group had more missing teeth, deeper periodontal pocket depth and more attachment loss than the Asian-American or Hispanic groups. However, the African-American group were less likely to report having a private dentist, had a greater proportion of smokers and a greater proportion of unskilled individuals. The profile of subgingival species differed among the three ethnic/racial groups with A. actinomycetemcomitans, N. mucosa, S. noxia and T. socranskii significantly elevated in the Asian-American group and P. micros significantly elevated in the African-American group. When subset by occupational status, numbers of missing teeth, pocket depth, attachment level and prior disease activity were all found increased in the unskilled relative to the professional group. Local factors including the mean % of sites with plaque, marginal gingival erythema, bleeding upon probing and suppuration were also elevated in the unskilled group. The microbial profile differed among the 3 occupational groups with the unskilled group having elevated numbers of species associated with destructive periodontal diseases. CONCLUSIONS: Although greater destructive periodontal disease prevalence and severity were found in the African-American group, these results suggest that environmental and demographic variables, such as occupational status, may have a greater influence on risk indicators associated with disease prevalence and progression in these populations.     

Plasmids in Actinobacillus actinomycetemcomitans strains isolated from periodontal lesions of patients with rapidly destructive periodontitis

Several strains of Actinobacillus actinomycetemcomitans newly isolated from periodontal lesions of patients with rapidly destructive periodontitis were all shown to possess identical plasmid profiles consisting of 4 plasmids. The largest plasmid, 20 MegaDalton (MDa), was also found in reference strains. Two different methods were used for isolation of the plasmids; the large 20 MDa plasmid (pHRP1) was found using the Kado and Liu method only. The 3 small plasmids of 7.0, 5.2 and 4.0 MDa (pHRP2, pHRP3, pHRP4), respectively, were seen using the Birnboim and Doly method. These plasmids are so far to be regarded as cryptic; no phenotypical characters have been linked to their presence. The large 20 MDa plasmid was found in all strains examined, and may be a genotypical marker for the A. actinomycetemcomitans species.     

Chlamydia pneumoniae together with collagenase-2 (MMP-8) in periodontal lesions

OBJECTIVE: Dental infections may be associated with subsequent atherosclerosis. In this regard we wanted to study if traces of Chlamydia pneumoniae can be found from deep periodontal pockets characterized with elevated collagenase-2 [matrix metalloproteinase (MMP)-8] levels in gingival crevicular fluid (GCF). Chlamydia pneumoniae has not previously been found to infect the oral cavity. SUBJECTS AND METHODS: Subgingival samples of dental plaque were collected from 31 teeth in 12 adult periodontitis patients by means of sterile curettes and examined for C. pneumoniae using a quantitative PCR technique. GCF samples were also collected and assayed by an immunofluorometric assay (IFMA) for MMP-8. RESULTS: Chlamydia pneumoniae RNA was demonstrated in a sample from one of the patients studied. Periodontal treatment eliminated the C. pneumoniae from the patient's subgingival dental plaque as well as reduced GCF MMP-8 level. CONCLUSIONS: Our findings suggest that C. pneumoniae, which is not normally thought to be involved in periodontitis, can be found in dental plaque.     

Difficulties encountered in the search for the etiologic agents of destructive periodontal diseases

The present paper outlines some of the difficulties encountered in the search for the etiologic agents of destructive periodontal diseases. These include technical problems such as acquiring an appropriate microbial sample, as well as difficulties in the dispersion, cultivation and identification of isolates in that sample. Many of these difficulties are currently being successfully addressed. A second set of problems is more conceptual in nature. These include difficulties in distinguishing between periodontal diseases and determining the state of activity of periodontal lesions. In addition, complexes of organisms and/or sequences of species may be involved in the progress of lesions. A further problem is encountered in attempting to distinguish overgrowths of opportunistic species from increases in proportions of true pathogens. Finally, it appears likely that different infections occur at the same time in a single oral cavity. The technical and conceptual difficulties eventually filter down to the data analytical step and present numerous problems to the analyst. With all of these difficulties in mind, it is not surprising that the etiologic agents of destructive periodontal diseases are not clearly defined. However, improvement in technological assessments of the microbiota and clinical evaluation of the disease should permit reasoned approaches to be taken. The delineation of the etiologic agents of destructive periodontal diseases will be, of necessity, a multistage iterative process. Etiologic agents will be suggested by predominant cultivable studies and hypotheses concerning subsets of these agents tested using more specific procedures such as selective media, immunofluorescent techniques or DNA probes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Soluble Fcγ receptors in periodontal lesions

Soluble Fcγ-binding components were detected in gingival fluid from periodontal lesions by incubation with biotinylated human Fcγ fragments. FcγIII receptor was identified by incubation of gingival fluid with monoclonal antibody. Sodium dodecyl sulfate-polyacrylamide gel electophoresis and Western transfer showed that most of the Fcγ-binding components had minimal mobility in a 4–15% gradient gel under nonreducing conditions. Under reducing conditions, the main band of Fcγ-binding components in gingival fluid migrated corresponding to protein A of 49 kDa. The pattern of Fcγ-binding components was similar in serum and gingival fluid except for the observation in gingival fluid of Fcγ-binding components migrating like standard proteins of 19 to 20 kDa, a size that corresponds to the polypeptide part of FcγII receptor and FcγIII receptor.     

无托槽隐形矫治器对牙周炎错胎患者的疗效观察

目的观察无托槽隐形矫治器对中、重度牙周炎错胎患者的治疗效果。方法牙周炎错胎畸形患者9例,其中男性5例,女性4例,平均年龄37．8岁。多数牙齿均有不同程度的牙周附着丧失,少数牙齿为重度牙周附着丧失、牙齿松动Ⅰ～Ⅱ度、牙槽骨吸收至根尖1／3。Ⅰ类错胎患者1例,Ⅱ类错骀患者5例,Ⅲ类错骀患者3例。经牙周基础治疗,控制牙周炎症后开始正畸治疗,均为非拔牙矫治,全部采用无托槽隐形矫治技术矫治。结果隐形矫治疗程最短6个月,最长17个月,平均疗程12．5个月。9例患者咬合关系和面型都得到明显改善,前牙殆创伤消除,牙周炎症控制良好,治疗后牙周探诊深度减小。结论无托槽隐形矫治器对牙周炎错骀患者的治疗是有效的,有利于矫治过程中口腔卫生维护和牙周治疗。