复方茶多酚含漱液对正畸儿童牙面菌斑中致龋菌的影响

目的观察复方茶多酚含漱液对正畸儿童牙面菌斑中细菌总数和变形链球菌数的影响,以及牙菌斑内原位pH的改变。方法选择42例戴用固定矫治器的正畸儿童,随机分为2组,试验组用复方茶多酚含漱液漱口,对照组用蒸馏水漱口。分别于戴用矫治器前,戴入后1月采集上下颌牙唇颊面菌斑,测定菌斑中细菌总数及变形链球菌数,同时测定牙菌斑原位pH。结果对照组戴用后1月,细菌总数及变形链球菌数较戴用前明显增加(P0.01),牙菌斑原位pH较戴用前降低(P0.01)。试验组与对照组戴用后1个月相比,试验组细菌总数及变形链球菌数明显少于对照组(P0.01),牙菌斑原位pH高于对照组(P0.01)。结论戴用固定矫治器后,牙面菌斑内细菌总数及变形链球菌数较戴用前增加,牙菌斑原位pH较戴用前降低,应用茶多酚含漱液可明显抑制正畸儿童口腔内变形链球菌数,减少龋坏发生。     

固定矫治器戴入前后牙周可疑病原菌和牙周临床指数的变化

目的:固定矫治器戴入前后的不同时间进行龈缘菌斑的微生物学检查和牙周状况的临床检查,以探讨固定矫治器戴入前后牙周可疑病原菌和牙周状况的动态变化过程.方法:选择18名固定正畸患者,于矫治器戴入前和戴入后1、3、6月分别检查16、41牙位的菌斑指数、牙龈指数、探诊深度、探诊出血,并在近中颊侧颊轴角处采集龈缘菌斑样本,采用细菌培养鉴定方法测定牙周可疑病原菌的检出量(CFU/g)和检出率.结果:与基线相比,观察期内龈缘菌斑的G￣产黑色素厌氧杆菌检出量和检出率在两个牙位均升高(P＜0.05),41的优杆菌、弯曲杆菌、拟杆菌、普氏菌亦有升高(P＜0.05).临床指标中16的牙龈指数(颊侧)和探诊深度(颊、舌侧)升高;41的菌斑指数(舌侧)降低(P＜0.05).结论:固定矫治器戴入后虽然可通过严格的口腔卫生指导有效控制牙面菌斑,但仍可引起牙周可疑病原菌增加.     

固定矫治器对口腔菌群的影响

目的利用PCR-DGGE方法探讨戴用牙齿固定矫治器对口腔菌群的影响。方法从20例健康的牙齿正常个体和30例戴用固定矫治器的正畸患者的唾液中提取细菌基因组总DNA,利用聚合酶链式反应—变形梯度凝胶电泳(PCR-DGGE)方法获取口腔菌群的分子指纹图谱,对其进行相似性和多样性的分析以及优势条带的序列分析。结果 PCR-DGGE可明确将正常个体和正畸患者分成2个簇,且正畸患者口腔菌群的多样性明显增加,优势菌群发生转变,序列分析表明口腔链球菌数量明显减少,假单胞菌成为优势菌型。结论戴用固定矫治器能改变口腔菌群分布,引起口腔中有益菌的减少,促使致病菌增长,导致口腔菌群失调。     

不同正畸方式对患者唾液中变形链球菌和乳杆菌水平的影响CSCD

目的 探讨配戴隐形矫治器和固定矫治器的患者唾液中变形链球菌和乳杆菌的水平及其他唾液指标,为该类患者的治疗提供参考。方法 本研究共纳入80名患者并分为两组,其中隐形矫治器组患者[n=40,(20.4±1.7)岁]采用隐形矫治器治疗,固定矫治器组患者[n=40,(21.3±1.7)岁]采用固定矫治器治疗。正畸治疗开始前(t0)、正畸治疗第3个月(t1)和正畸治疗第6个月(t2)分别评估牙菌斑指数、唾液缓冲能力、唾液流量以及唾液中变形链球菌和乳杆菌的水平。结果 隐形矫治器组患者的菌斑指数随着时间的推移始终维持在0级,而固定矫治器组患者的菌斑指数随着时间的推移呈显著上升趋势。此外,在t2时,37.5%的固定矫治器组患者出现变形链球菌水平的增加及乳杆菌水平的增加(均P<0.05)。结论 与固定矫治器组相比,隐形矫治器治疗的受试者在治疗6个月后唾液微生物数量较低。不同矫治器类型治疗时必须采用不同的菌斑及微生物控制方式。     

应用16S rDNA检测固定矫治患者牙周可疑病原菌变化研究

应用16S rDNA检测固定矫治患者龈下菌斑中牙周可疑病原,探讨戴用固定矫治器对牙周组织健康的影响。随机选择36例治疗时间超过6个月的固定矫治患者组成实验组,29例未经正畸治疗者组成对照组。分别检验特定部位牙周临床指数并收集龈下菌斑样本。采用16S rDNA检测9种牙周可疑致病菌。实验组与对照组相比牙龈指数、牙周袋深度、探诊出血差异有明显统计学意义(P<0.05);牙周可疑病原菌中牙龈卟啉菌、齿垢密螺旋体在实验组的检出率明显高于对照组(P<0.05)。固定矫治器戴入可引起患者牙周可疑病原菌的明显变化。     

口腔卫生预防措施对固定正畸患者牙周菌群和牙周临床指数的影响

目的 采用牙周洁治和强化的口腔健康教育方法,通过检测牙周菌群和牙周临床指数的动态变化,探讨口腔卫生预防措施对固定正畸患者牙周菌群的影响。方法 选择正畸初诊患者20例,平均分为试验组（T组）和对照组（C组）。于正畸治疗开始前检查右上颌第一磨牙16和右下颌中切牙41牙周状况,并采集其近中颊轴嵴处龈缘菌斑做细菌分离培养。T组于治疗前进行全口洁治,每月复诊加力时均给予口腔卫生检查,强调口腔卫生的重要性;C组仅在初诊时进行口腔卫生指导,其余不作处理。2组患者分别于矫治器安装后1、3和6个月进行临床及细菌学检查。结果 随观察时间的延长,T组颊侧菌斑指数和牙龈指数在第1、3、6个月时较基线降低;C组颊侧菌斑指数第6个月时较基线降低,舌侧探诊深度则升高（P＜0.05）。细菌检出率和检出量的变化在T组可见韦荣球菌属降低而弯曲杆菌属和Gn产黑色素厌氧杆菌（BPAR）升高,C组消化链球菌属和BPAR升高（P＜0.05）;BPAR在第3个月、消化链球菌属在第6个月时T组检出率低于C组（P＜0.05）,而细菌检出量和牙周临床指数在2组间没有观测到处理因素的作用（P＞0.05）。结论 正畸前即存在牙龈炎的患者,建议进行预防性牙周洁治;牙周洁治必须和口腔卫生教育、正确的日常菌斑控制措施结合进行。     

双歧杆菌预防早产儿坏死性小肠结肠炎的疗效观察

目的 探讨双歧杆菌预防早产儿坏死性小肠结肠炎(NEC)的疗效.方法 随机分成试验组和对照组,对照组给予常规治疗,试验组在对照组基础上给予双歧杆菌治疗.观察两组不同胎龄和不同出生体重早产儿NEC患病率、治疗前后肠道各菌群变化的差异.结果 (1)试验组NEC总发生率显著低于对照组,差异有统计学意义(P＜0.01);(2)试验组出生体重＜1500g早产儿NEC发生率显著低于对照组,差异有统计学意义(P＜0.05);(3)治疗后试验组细菌总数、球菌总数及杆菌总数上升幅度显著大于对照组,差异均有统计学意义(P＜0.01);治疗后试验组杆球菌比值较对照组显著下降,差异有统计学意义(P＜0.01).结论 双歧杆菌可有效预防早产儿坏死性小肠结肠炎.     

牙菌斑形成早期微生物定植规律的定量PCR研究

目的观察牙面彻底清洁后24 h内牙面上定植的变异链球菌、伴放线放线杆菌和总微生物的数量变化。方法 8名健康成人接受全口洁治后,分别于6、12和24 h收集龈上菌斑,提取菌斑内细菌的基因组DNA。设计变异链球菌、伴放线放线杆菌和总菌特异性引物,获得目的基因,克隆于大肠埃希菌DH5α感受态细胞,测序后获得质粒标准品。将样本和梯度稀释的质粒标准品进行SYBR Green I实时荧光定量PCR检测,绘制标准曲线,确定样本中变异链球菌、伴放线放线杆菌和总菌DNA拷贝数。结果牙面彻底清洁6 h后即有大量变异链球菌定植,变异链球菌拷贝数占总菌的0.32%,24 h后增加到0.67%。12 h时定植的变异链球菌拷贝数高于6 h,差异有统计学意义（P=0.031）,24 h后继续增加（P=0.024）。12 h时定植的总菌拷贝数高于6 h,差异有统计学意义（P=0.004）,24 h后继续增加（P=0.042）。牙菌斑中伴放线放线杆菌的拷贝数低于103。结论早期牙菌斑中12 h定植的变异链球菌和总菌数量高于6 h,且24 h内不断增加,仅有少量伴放线放线杆菌定植。     

赤藓糖醇对主要致龋链球菌及耐氟菌株生长和产酸的影响

目的通过赤藓糖醇对变形链球菌、远缘链球菌及其耐氟菌株混合菌生长和产酸影响的体外研究,为赤藓糖醇防龋作用的机理提供制论依据。方法采用最小抑菌浓度递增法对变形链球菌（S.mutans ATCC 25175,S.m）、远缘链球菌（S.sobrinus 6715,S.s）进行氟化钠体外诱导耐氟菌株（S.m-FR、S.s-FR）,利用液体稀释法配制赤藓糖醇TSB液8个浓度,分别加入含有变形链球菌、远缘链球菌及其耐氟菌株的细菌混悬液48 h,用比浊法观察其对混合菌生长的影响,并用pH计测定培养前后上清液的△pH值。结果吸光度A值和△pH值实验前后与对照组相比最低浓度为12%时差异均有统计学意义（P〈0.05）,且随着浓度的升高A值和△pH值均下降。结论赤藓糖醇能抑制变形链球菌、远缘链球菌及耐氟菌株混合菌生长和产酸,并且随着浓度的升高抑制作用增强。     

天然蜂胶牙泰治疗冠周炎的临床实验研究

作者将用蜜蜂产品蜂胶制成的蜂胶牙泰（酊剂）用于治疗冠周炎,同时与１％碘甘油对比观察,以评价蜂胶牙泰的临床疗效及体内抑菌作用。选冠周炎患者６０例,试验组４５例（其中３０例同时兼作体内抑菌试验）,对照组１５例。体内抑菌试验结果表明３０例经蜂胶牙泰治疗后冠周袋内５种主要致病菌菌落数、厌氧菌总数、需氧菌总数、总菌数明显下降（Ｐ＜０．０１）,而１５例经１％碘甘油治疗后盲袋内细菌数下降不明显（Ｐ＞０．０５）。临床实验研究结果,蜂胶牙泰组有效率为４８．９％,１％碘甘油组有效率为２０．０％（Ｐ＜０．０５）。蜂胶牙泰治疗冠周炎临床疗效优于传统药物１％碘甘油,且对口腔粘膜无刺激无毒副作用,是一种有前途的冠周炎局部用药。     

Differences in microbiological composition of saliva and dental plaque in subjects with different drinking habits

Several foods have been shown to contain natural components (especially polyphenols) which display anti-adhesive properties against Streptococcus mutans, the aetiological agent responsible for dental crown caries, as well as inhibition of glucosyltransferases, which are the S. mutans enzymes involved in the synthesis of an adherent, water-insoluble glucan from sucrose. Other studies have demonstrated an in vitro action on oral plaque biofilm formation and desorption. This study evaluated whether the activity displayed in vitro by food compounds could affect the microbiological composition of saliva and dental plaque of subjects with a diet rich in these foods, comparing the results with those obtained from subjects with a different diet. The foods considered were: coffee, barley coffee, tea and wine. A total of 93 subjects were recruited into the study. Six samples of both plaque and saliva were collected from each subject at roughly one-monthly intervals. Total bacteria, total streptococci, S. mutans and lactobacilli counts were determined by culture in both saliva and dental plaque. The highest bacterial titres were recorded for the control population, while each drinking habit subgroup showed counts roughly one log lower than the controls. These differences in bacterial counts proved statistically significant (P<0.05). As far as dental plaque was concerned, while total counts did not significantly vary per mg of plaque in the subjects belonging to the different drinking habit subgroups, a significant decrease (P<0.05) was observed in those subjects drinking coffee, tea, barley coffee and wine when mutans streptococci and lactobacilli were evaluated. In several cases a more than one log decrease was observed. Plaque indices were also determined, and a significant (P<0.05) reduction in values was recorded in the subjects belonging the specific drinking habit subgroups compared to the control group. This study indicates that there is a correlation between consumption of specific foods and oral health in terms of reduced plaque deposition and lower counts of odontopathogens.     

Prevalence of putative periodontopathogens in subgingival dental plaques from gingivitis lesions in Korean orthodontic patients

The objective of this study was to detect and compare the presence of periodontopathogens in the subgingival plaques of gingivitis lesions in adults who wore fixed orthodontic appliances, as opposed to adults who did not wear any orthodontic appliances. Thirty-six individuals participated in this study. Nineteen of these subjects did not wear any orthodontic appliances, and these subjects comprised the control group. The other 17 individuals had been wearing fixed orthodontic appliances for at least 3 months each. After a periodontal examination, we collected subgingival plaque samples from the gingivitis lesions of each patient. Using PCR based on 16S rDNA, we detected the presence of 6 putative periodontopathogenic species, Treponema denticola, Porphyromonas gingivalis, Tannerella forsythia (formerly Bacteroides forsythus), Prevotella nigrescens, Prevotella intermedia, and Actinobacillus actinomycetemcomitans. With regard to the presence of individual periodontopathogens, we found that T. forsythia, T. denticola, and P. nigrescens were significantly more common in the samples obtained from the orthodontic patients than in the samples obtained from the non-orthodontic patient controls. Our results indicate that the local changes associated with the wearing of fixed orthodontic appliances may affect the prevalence of periodontopathogens in subgingival dental plaques.     

A Computational Fluid Dynamic Analysis of Peri-Bracket Salivary Flow Influencing the Microbial and Periodontal Parameters

Fixed vestibular appliances decrease the “self-cleansing” action of saliva and promote aggregation of dental plaque by disturbing the salivary flow field on tooth surfaces, leading to a higher prevalence of enamel demineralization and periodontal diseases. In the current study, we investigated the salivary dynamic characteristics of plaque retention and periodontal status around appliances during orthodontic treatment. By reconstructing lower central incisors and orthodontic appliances, we simulated saliva flow on the tooth surface and then characterized and quantified the salivary flow pattern surrounding the bracket and archwire. In parallel, we tested the total peri-bracket bacterial counts and periodontal status to assess interrelations. Our results demonstrate that orthodontic appliances disturb the salivary flow field on tooth surfaces and can lead to a decrease in salivary velocity and an increase in bacterial numbers. Local vortexes forming in the areas gingival to the bracket, together with the narrow space limitation, contributed to the periodontal inflammatory response. This study confirms that changes in salivary flow are an obvious predisposing factor for bacterial accumulation, and advances the ability to replicate, in vitro, the salivary characteristics of plaque retention and periodontal status around appliances during orthodontic treatment.     

Influence of the fluoride releasing dental materials on the bacterial flora of dental plaque

The assessment of influence of silver-free, fluor releasing dental materials on dental plaque bacteria quantity. 17 patients were included into the study. 51 restorations were placed following manufacturers recommendations. Following materials were used: conventional glassionomer Ketac-Molar ESPE, resin modified glassionomer Fuji II LC GC and fluor containing composite Charisma Heraeus Kulzer Class V restorations were placed in following teeth of upper and lower jaw: canines, first bicuspids, second bicuspids. Sound enamel was a control. After 10 weeks the 72 hours old dental plaque was collected from surface of restorations and control using sterile probe. Total amount of 68 dental plaques were investigated. Each plaque was placed on scaled and sterile aluminum foil. The moist weight of dental plaque was scaled. Dental plaque was moved into 7 ml 0.85% NaCl solution reduced by cystein chlorine hydrogen and disintegrated by ultrasounds (power:100 Watt, wave amplitude: 5 micorm). The suspension of dental plaque was serially diluted from 10(-4) to 10(-5) in sterile 0,85% NaCl solution, and seeded with amount of 0.1 ml on appropriate base. In dental plaque trials the amount of cariogenic bacteria was calculated--Streptococcus mutans, Streptococcus, Lactobacillus, Veillonella and Neisseria, and also total amount of aerobic and anaerobic bacteria was measured. Microbiologic studies were performed in Institute of Microbiology, Medical University, ?ód?. Statistical analysis of collected data was accomplished. In 72 hours old dental plaques collected from the surfaces of Ketac -Molar, Fuji II LC, Charisma after 10 weeks since being placed into the class V cavity, results show no statistically significant differences in the amount of Streptococcus mutans, Streptococcus spp., Lactobacillus spp., Veillonella spp., Neisseria spp, in total amount of aerobic and anaerobic bacteria and in the quantity proportion of Streptococcus mutans versus Streptococcus spp. in comparison with control trail. Results show no statistically significant differences in the amount of listed above bacteria and in the proportion of Streptococcus mutans versus Streptococcus spp. in 72 hours old dental plaques collected from surfaces of investigated restorative materials.     

Influence of topical fluoridation of glass ionomer cements on inhibitory activity on cariogenic bacteria

Glass ionomer cements are important options in restorative and preventive dentistry due to their adhesion to the tooth surface and fluoride release, which can decrease the risk of recurrent caries. The aim of this study was to define, in vivo, the influence of the topical use of fluoride gel on dental plaque bacteria growing on the glass ionomer cement. Fifteen patients were included into this study. Thirty five class V restorations from the glass ionomer cement (Ketac Molar Aplicap, ESPE Germany) were placed in the patient's one half of the lower jaw. The sound enamel of other side of the lower jaw was treated as a control. After 6 month 72 old dental plaque was collected from the surfaces of restorations and the surfaces of the sound enamel. Total amount of 30 dental plaque samples were investigated according to the previously described method (17). In dental plaque samples the amount of Streptococcus mutans was calculated at the Department of Microbiology, Medical University of Lód?. Next the topical application of fluoride gel (Fluormex) was performed on the surfaces of glass ionomer (Ketac Molar) fillings and the sound enamel. The patients were asked not to clean the teeth for 72 h. After this time the dental plaque was again collected from the surfaces of restorations and sound enamel. Statistical analysis of collected data was accomplished and showed no statistically significant differences in the amount of Streptococcus mutans both on Ketac Molar and the enamel before and after the topical use of fluoride gel. It was concluded that the topical fluoridation of glass ionomer cement did not affect Streptococcus mutans growing in dental plaque.     

A high molecular mass cranberry constituent reduces mutans streptococci level in saliva and inhibits in vitro adhesion to hydroxyapatite

Previous investigations showed that a high molecular mass, non-dialyzable material (NDM) from cranberries inhibits the adhesion of a number of bacterial species and prevents the co-aggregation of many oral bacterial pairs. In the present study we determined the effect of mouthwash supplemented with NDM on oral hygiene. Following 6 weeks of daily usage of cranberry-containing mouthwash by an experimental group (n = 29), we found that salivary mutans streptococci count as well as the total bacterial count were reduced significantly (ANOVA, P < 0.01) compared with those of the control (n = 30) using placebo mouthwash. No change in the plaque and gingival indices was observed. In vitro, the cranberry constituent inhibited the adhesion of Streptococcus sobrinus to saliva-coated hydroxyapatite. The data suggest that the ability to reduce mutans streptococci counts in vivo is due to the anti-adhesion activity of the cranberry constituent.     

Antimicrobial effects of a pulsed electromagnetic field: an in vitro polymicrobial periodontal subgingival biofilm model

Abstract

The objective was to test the influence of a pulsed electromagnetic field (PEMF) on bacterial biofilm colonization around implants incorporated with healing abutments. Healing abutments with (test group) and without (control group) active PEMF devices were placed in a multispecies biofilm consisting of 31 different bacterial species. The biofilm composition and total bacterial counts (x10⁵) were analyzed by checkerboard DNA-DNA hybridization. After 96?h, the mean level of 7 out of the 31 bacterial species differed significantly between groups, namely Eubacterium nodatum, Fusobacterium nucleatum ssp. nucleatum, Streptococcus intermedius, Streptococcus anginosus, Streptococcus mutans, Fusobacterium nucleatum ssp. Vicentii and Capnocytophaga ochracea were elevated in the control group (p?<?0.05). The mean total bacterial counts were lower in the Test group vs the control group (p?<?0.05). An electromagnetic healing cap had antimicrobial effects on the bacterial species and can be used to control bacterial colonization around dental implants. Further clinical studies should be conducted to confirm these findings.     

Nested PCR for detection of mutans streptococci in dental plaque

AIMS: Mutans streptococci such as Streptococcus mutans and Streptococcus sobrinus have been implicated in human dental caries. In an attempt to develop a rapid and sensitive method for detecting Strep. mutans and Strep. sobrinus in dental plaque, a nested PCR amplification based on the 16S rRNA gene was employed. METHODS AND RESULTS: A universal set of PCR primers for bacterial 16S rRNA gene was introduced for the first PCR, and then two sets of primers specific for the 16S rRNA gene sequences of either Strep. mutans or Strep. sobrinus were used for the second PCR. Eighteen plaque samples were analyzed, and a nested PCR was shown to be more sensitive for detecting Strep. mutans and Strep. sobrinus than direct PCR. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: The 16S rRNA gene-based nested PCR method is a rapid and sensitive method for the detection of mutans streptococci, and may also be suitable for carrying out large-scale studies on the cariogenicity of mutans streptococci.