蜂胶涂膜对变形链球菌生长和黏附的抑制作用

目的观察蜂胶涂膜对变形链球菌生长和黏附的抑制作用。方法采用纸片琼脂扩散法观察10、25、50g/L和100g/L蜂胶防龋涂膜对变形链球菌c型和d型的抑菌作用。以蜂胶涂膜涂布黏附板,置变形链球菌培养液中培养,观察其抗黏附效果。结果各浓度蜂胶涂膜及基质都能够抑制细菌生长和黏附,且抑菌作用呈现明显的浓度依赖性,100g/L涂膜组的抑菌效果与1.6g/L洗必泰溶液无显著性差异(P>0.05)。结论25~100g/L蜂胶涂膜均可以有效抑制变形链球菌c型和d型的生长黏附。     

重度龋儿童远缘链球菌基因多态性研究

目的 采用随机引物聚合酶链反应(arbitrarily primed-polymerase chain reaction,AP-PCR)法初步探讨远缘链球菌在重度低龄儿童龋(severe early childhood caries,S-ECC)儿童与无龋儿童口腔中基因型分布的情况,分析其与婴幼儿龋发生之间的关系.方法 选取北京市海淀区和西城区14所幼儿园178名42～54个月龄儿童,S-ECC(患龋牙数≥5)组87例,无龋组91人.嚼蜡法采集刺激性唾液进行分离培养,典型菌落行革兰染色、生化鉴定并保种,提取基因组DNA,PCR鉴定变形链球菌和远缘链球菌,AP-PCR法对远缘链球菌临床分离株行基因型分析.结果 S-ECC组远缘链球菌检出率18%(16/87),显著高于无龋组的3%(3/91),差异有统计学意义(P＜0.01).53株远缘链球菌临床分离株共检出22种基因型,S-ECC组个体基因型为1～3种,无龋组均为1种;此外,S-ECC组3名个体间存在相同基因型的菌株.S-ECC组基因型数与龋失补牙数间存在相关性(r=0.50,P＜0.05).结论 S-ECC儿童远缘链球菌检出率明显高于无龋儿童,且菌株间存在基因多态性,个体携带基因型的种类数与其致龋性间存在相关性;远缘链球菌无关个体间存在相同基因型的菌株.     

人工合成变形链球菌表面蛋白多肽体外抗粘附实验

目的 :观察一种人工合成变形链球菌表面蛋白多肽体外抗粘附作用。方法 :H3标记细菌羟磷灰石法观察多肽体外抗粘附作用。结果 :对于S .mutansIngbritt和S .sobrinus 6 715 ,1pmol%D 1μmol均有抑制作用 ,抑制作用随多肽浓度增加而增加。多肽浓度在 1μmol有较强抑制作用。 结论 :人工合成变形链球菌表面蛋白多肽具有体外抗粘附 ,降低变形链球菌的粘附于羟磷灰石的作用 ,并且该多肽无直接抑菌作用 ,有可能成为一种新的生物防龋制剂。     

甲壳胺复合物影响变形链球菌生长、代谢的实验室研究

目的观察甲壳胺、荼多酚单一组分及甲壳胺复合物对口腔致龋菌生长、粘附和代谢产酸的影响。方法采用0．5％甲壳胺、0．25％茶多酚以及同等浓度的甲壳胺、茶多酚复合物对变形链球菌、远缘链球菌进行抑菌实验、抗粘附实验、解吸附实验以及产酸抑制实验。结果0．5％甲壳胺可抑制变链菌对毛细管的粘附．并促进附着于粘附板上的变链菌脱落，产酸实验中，0．5％甲壳胺和0．25％荼多酚可减少终末pH下降和乳酸量生成，甲壳胺复合物对变链菌的抑制粘附和产酸作用明显高于单一成分组。结论甲壳胺复合物对口腔致龋菌生长、粘附和代谢产酸均有明显的抑制，提示甲壳胺及荼多酚作为天然抗菌斑附着剂，用于龋病预防具有一定的价值和可行性。     

洗必泰对变形链球菌、远缘链球菌耐氟菌株与亲代菌株生长抑制的测定

目的：通过洗必泰对变形链球菌、远缘链球菌耐氟菌株与亲代菌株生长抑制的测定，探讨一种新的防龋途径。方法：将醋酸洗必泰液稀释成不同的浓度，分别加入变形链球菌、远缘链球菌及耐氟菌株菌悬液，测得最小抑菌浓度（MIC）、最小杀菌浓度（MBC）。结果：洗必泰对变形链球菌、远缘链球菌及耐氟菌株均有抑菌、杀菌作用，4种细菌最小抑菌浓度（MIC）均值为338μg/L，最小杀菌浓度（MBC）均值为375μg/L。结论：洗必泰可有效抑制变形链球菌、远缘链球菌及耐氟菌株生长。     

表兄链球菌的检测与儿童猛性龋的关系

目的：探讨表兄链球菌(Streptococcus sobrinus,S. sobrinus)与儿童猛性龋的关系。方法：根据前期郑州市区猛性龋调查结果,随机抽样选择3～5岁儿童66例,其中猛性龋、普通高龋及无龋组各22例。采用TYCSB培养基作变形链球菌(Streptococcus mutans, S. mutans )及S. sobrinus初步筛选,结合生理生化鉴定,并采用聚合酶链反应作最终鉴定。采用 SPSS10.0软件包对实验组与对照组S.mutans和S.sobrinus的检出率进行χ²检验,组间均数作t检验。结果： S. sobrinus在各组儿童牙菌斑中均不能脱离S. mutans而单独检出,猛性龋组S. mutans检出率高于高龋组,差异无显著性(P>0.05),而2组儿童S. sobrinus检出率的差异有显著性(P<0.05);猛性龋组与无龋组S. mutans检出率差异显著(P<0.05),S. sobrinus检出率差异显著(P< 0.01)。同时检出S. mutans和S. sobrinus的样本,其猛性龋的发生率及龋失补牙数、龋失补牙面数和平滑面龋均数与只能检出S. mutans及2种细菌均不能检出的样本的差异有显著性(P< 0.01)。结论：S. mutans与S. sobrinus是儿童猛性龋的主要致病菌,S. sobrinus与儿童猛性龋的发生有关。S. sobrinus对儿童猛性龋的发生、发展具有协同作用。     

套式PCR检测唾液中变形链球菌及远缘链球菌

目的 探索一种快速、简便地从人类唾液中同时检测变形链球菌和远缘链球菌的方法。方法 分别以变形链球菌gtfI和远缘链球菌gtfB基因设计两组成套引物，首先用套式PCR（二次PCR）检测变形链球菌和远缘链球菌标准株和临床株，然后用套式PCR直接从唾液中检测这两种细菌。结果 变链菌（血清型c,e,f)的标准株及临床株第1次PCR扩增产物为517bp，第2次扩增产物为468bp；远缘链球菌（血清型d,g)及道勒链球菌（血清型h)的标准株及临床株第1次PCR扩增产物为712bp，第2次扩增产物为663bp;其他异种菌均不能扩增出产物，因此该PCR检测具有高度的特异性。细菌纯培养物及唾液PCR检测的敏感性分别是：第1次PCR为10^5CFU，第2次PCR为10^3CFU。结论 套式PCR能快速在人类唾液中同时检测变形链球菌和远缘链球菌。该检测方法有望运用于临床检测，对揭示两种细菌与龋病发生关系的研究具有一定价值。     

Relationship of quantitative salivary levels of Streptococcus mutans and S. sobrinus in mothers to caries status and colonization of mutans streptococci in plaque in their 2.5-year-old children

Abstract – Objectives: The aim of this study was to assess the relationships of quantitative salivary levels of Streptococcus mutans and S. sobrinus in mothers with the colonization of mutans streptococci (MS) in plaque and caries status in their 2.5‐year‐old children. Furthermore, the dynamics of caries status in the children was evaluated in a 2‐year follow‐up survey. Methods: After oral examination of 54 mother‐and‐child pairs, the saliva samples from the mothers and the plaque samples from the children were collected. The levels (log DNA copies/ml saliva) of S. mutans and S. sobrinus were quantified using real‐time polymerase chain reaction (PCR) assays, while MS in the plaque samples were detected using a cultivation method. In addition, 50 of the 54 children participated in a 2‐year follow‐up survey of caries prevalence. Results: In the 2.5‐year‐old children, the percentage of dft‐positive subjects and mean number of dft were significantly higher in the MS(+) group when compared with the MS(?) group. Findings from the 2‐year follow‐up survey indicated that MS(+) subjects had a persistently higher mean number of dft at 4.5 years. The 2.5‐year‐old children were divided into three groups based on the quantitative levels of salivary S. mutans and S. sobrinus in their mothers: those whose mothers had low levels of S. mutans (<4 log DNA copies/ml) and S. sobrinus (<2) (group 1); those whose mothers had a high level of S. mutans (≥4) and low level of S. sobrinus (<2) (group 2); and those whose mothers had high levels of both (≥4 and ≥2, respectively) (group 3). Among the three groups, the percentages of MS(+) and dft‐positive children were highest in group 3 and lowest in group 1. Furthermore, multiple logistic regression analyses revealed that grouping the mothers based on salivary level of S. mutans and S. sobrinus was an efficient means to predict both MS colonization (OR = 2.96) and prevalence of dental caries (OR = 9.39) in children at 2.5 years of age. Conlusions: In the 54 mother‐and‐child pairs tested, the maternal salivary levels of S. mutans and S. sobrinus determined by real‐time PCR were significantly related to MS colonization in plaque as well as dental caries in their children at 2.5 years of age. Thus, determination of maternal levels of both organisms using the present cut‐off values is proposed as an efficient method to indicate the risks of maternal transmission of MS and childhood dental caries.     

几种制剂对口腔主要致龋菌抑制作用的比较

目的 :研究玉洁纯、硫酸锌、茶多酚以及它们相对配伍的制剂应用于龋病预防的可能性。方法 :采用液体稀释法体外抑菌实验比较玉洁纯、硫酸锌、茶多酚以及它们配伍使用时对口腔主要致龋菌S .mutansIngbritt、S .sobrinus　 6 715的抑制效果。结果 :以上三种制剂均能有效地抑制主要致龋菌的生长 ,其中玉洁纯的抑菌效果最为显著 ;硫酸锌和茶多酚都不能有效地促进玉洁纯的抑菌作用。结论 :玉洁纯作为一种高效低毒的抑菌剂可以考虑用于龋病预防 ,硫酸锌对玉洁纯抑菌效果的影响有待进一步研究。     

唾液获得性膜原位葡聚糖与变形链球菌和茸毛链球菌附着关系的实验研究

通过离体实验观察了实验性获得性膜原位葡聚糖在变形链球菌Ｓ．ｍｕｔａｎｓ和Ｓ．ｓｏｂｒｉｎｕｓ附着牙面过程中的作用。结果表明：两菌具有相似的产生ＧＴＦ和原位葡聚糖的能力，但两菌附着量和附着率的差别较大。在有蔗糖和ＧＴＦ存在时，Ｓ，ｓｏｂｒｉｎｕｓ的附着率明显高于Ｓ．ｍｕｔａｎｓ．提示原位葡聚糖在Ｓ．ｓｏｂｒｉｎｕｓ的附着中起重要作用，Ｓ、ｓｏｂｒｉｎｕｓ主要以蔗糖依赖性机制定居牙面，而Ｓ．ｍｕｔａｎｓ主要以蔗糖非依赖性机制定居牙面。     

The effect of chlorhexidine varnish treatment on salivary mutans streptococcal levels in child orthodontic patients.

A chlorhexidine dental varnish was applied to the teeth of 26 children, ten to 17 years of age, in an attempt to limit the increase in colonization by mutans streptococci that normally accompanies the placement of fixed orthodontic appliances and to assess the acceptance of the application procedure. Despite the insertion of the appliances in the month following the varnish application, the numbers of detectable salivary mutans streptococci in the children were found to remain significantly lower than baseline values for seven months (p less than 0.01). Among the 26 children, 16 exhibited high counts (greater than 2.5 x 10(5) cfu/mL saliva) at baseline, but none exhibited such counts until three months post-treatment, when one child did. By seven months, eight children had high counts. No significant difference in effectiveness was observed between varnish formulations containing 10% or 20% chlorhexidine acetate, or between children of different ages or past caries experience. The lack of drop-outs and the results of a questionnaire indicated that acceptance of the treatment by the children was excellent. The study indicates that chlorhexidine varnish therapy was acceptable to the children and was effective in suppressing oral mutans streptococcal levels for long periods, even when used prior to the placement of fixed orthodontic appliances.     

Effects of Weight Watchers' diet on salivary secretion rate, buffer effect and numbers of mutans streptococci and lactobacilli

The aim of this investigation was to study how a change to the dietary regimen of the Weight Watchers' (WW) affected salivary secretion rate, buffer effect and number of cariogenic bacteria. Thirty-three women joining the WW were saliva sampled at the evening prior the day of the start of the dietary regimen and after 4 and 8 wk on the dietary regimen. No significant changes were found regarding saliva secretion rate and buffer effect. A significant decrease of salivary numbers of mutans streptococci and lactobacilli occurred. Between the 4th and 8th wk of dietary regimen an increase of cariogenic bacteria occurred but not back to the baseline values. At baseline 15 of the WW carried Streptococcus sobrinus in addition to Streptococcus mutans . The total number of salivary mutans streptococci and lactobacilli was significantly higher in those subjects. In conclusion the dietary regimen of the WW, based on food choice and distributions of meals in agreement with a non-cariogenic diet, reduced the number of cariogenic bacteria in most subjects, but not in all, while the secretion rate and buffer effect remained the same.     

中药五倍子对变形链球菌及远缘链球菌抑制作用的体外研究

目的：研究五倍子及其主要成分鞣酸在体外对变链菌及远缘链球菌的抑制作用，并摸索适宜剂型和浓度。方法：本实验采用纸片扩散法研究五种浓度五倍子煎剂，五倍子浸剂，鞣酸标准品抑制变链菌及远缘链球菌生长的作用。结果：65.2mL/L以上浓度五倍子煎剂，浸剂，鞣酸对变链菌及远缘链球菌生长均有抑制作用，其中五倍子浸剂抑菌作用最强。抑菌作用随着各剂型浓度的增国而增强。结论：五倍子可以抑制变链菌及远缘链球菌生长，其中浸剂效果最优，鞣酸组效果较差，可初步推测五倍子中含有其他协同鞣酸抑菌的成分。     

The effect of polyol-combinant saliva stimulants on S. mutans levels in plaque and saliva of patients with mental retardation

The effect of chewable saliva-stimulants on Streptococcus mutans levels in dental plaque and paraffin-stimulated whole saliva among participants who were mentally disabled was investigated. Over 64-days, 98 participants chewed one of four saliva-stimulating tablets five times/day. The tablets contained one of the following: xylitol (X) or sorbitol (S), or 1:1 mixtures of xylitol and erythritol (XE) or sorbitol and erythritol (SE). Consumption of xylitol and sorbitol in Groups X and S was 5.4 grams/day/ subject, and of each polyol in Groups XE and SE, consumption was 2.7 g/day/subject. Interproximal dental plaque and stimulated whole saliva were sampled at baseline, at Day 36, and Day 64. There was a statistically significant reduction of S. mutans in plaque and saliva counts in Groups X and XE. The percentage of S. mutans in total streptococci increased significantly in dental plaque in Group S but decreased in the other groups. The results suggest that xylitol-containing saliva stimulants may be more effective than sorbitol-containing products in controlling some caries-associated parameters in people who are mentally disabled. Also a relationship may exist between the pentitol-type xylitol and S. mutans , and erythritol may exert a specific biochemical effect on this organism, although further studies are needed.     

玉洁纯、硫酸锌对口腔主要致龋菌生长产酸的影响

目的：评价玉洁纯、硫酸锌对口腔主要致龋菌的影响,确定抑制细菌所需的浓度。方法：使用紫外分光光度计及ｐＨ电极检测不同浓度的药物及两者相对配伍使用时对口腔主要致龋菌－变形链球菌和远缘链球菌的抑制效果。结果：玉洁纯、硫酸锌均能有效地抑制变链和远链的生产和产酸,硫酸锌不能增强玉洁纯的抑制效果。结论：初步认为玉洁纯可作为龋病预防用药,硫酸锌在配方中的作用有待进一步探讨。     

Clinical and microbiological parameters in patients with self-ligating and conventional brackets during early phase of orthodontic treatment

Objective:To determine the effect of different bracket designs (conventional brackets and self-ligating brackets) on periodontal clinical parameters and periodontal pathogens in subgingival plaque.Material and Methods:The following inclusion criteria were used: requirement of orthodontic treatment plan starting with alignment and leveling, good general health, healthy periodontium, no antibiotic therapy in the previous 6 months before the beginning of the study, and no smoking. The study sample totaled 38 patients (13 male, 25 female; mean age, 14.6 ± 2.0 years). Patients were divided into two groups with random distribution of brackets. Recording of clinical parameters was done before the placement of the orthodontic appliance (T0) and at 6 weeks (T1), 12 weeks (T2), and 18 weeks (T3) after full bonding of orthodontic appliances. Periodontal pathogens of subgingival microflora were detected at T3 using a commercially available polymerase chain reaction test (micro-Dent test) that contains probes for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola.Results:There was a statistically significant higher prevalence of A actinomycetemcomitans in patients with conventional brackets than in patients with self-ligating brackets, but there was no statistically significant difference for other putative periodontal pathogens. The two different types of brackets did not show statistically significant differences in periodontal clinical parameters.Conclusion:Bracket design does not seem to have a strong influence on periodontal clinical parameters and periodontal pathogens in subgingival plaque. The correlation between some periodontal pathogens and clinical periodontal parameters was weak.     

The effect of orthodontic treatment on salivary flow, pH, buffer capacity, and levels of mutans streptococci and lactobacilli

Fixed orthodontic treatment has been shown to cause an increased incidence of enamel demineralisation. The purpose of this study was to investigate the changes in stimulated salivary flow rate, pH, buffer capacity, and the levels of mutans streptococci (MS) and lactobacilli in patients undergoing therapy with fixed orthodontic appliances. Saliva samples, plaque index scores and dietary histories were taken from 21 sequential patients before the start of treatment, and one month and three months after placement of brackets and bands. There was a statistically significant increase in stimulated salivary flow rate, pH, buffer capacity, plaque index scores, and in the levels of MS and lactobacilli after three months of active treatment. It is postulated that the balance between the cariogenic challenge posed by high levels of MS and lactobacilli, and the reparative effects of concurrent increases in salivary flow rate, pH and buffer capacity, determines the likelihood of mineral loss or gain over time. A failure to follow basic preventive measures may increase the risk for some patients of enamel decalcification during orthodontic treatment with fixed appliances.     

The effect of different formulations of chlorhexidine in reducing levels of mutans streptococci in the oral cavity: A systematic review of the literature

OBJECTIVES: The current study undertakes a systematic review of the literature in order to assess how long different formulations (solutions, gels and varnishes) of chlorhexidine (CHX) reduce the level of mutans streptococci (MS) in the oral cavity. SOURCES: A search of the PUBMED and LILACS databases was conducted through October 2005. STUDY SELECTION: Clinical studies evaluating the effects of CHX solutions, gels, or varnishes on MS levels were targeted (n=52). CONCLUSIONS: The studies varied greatly in quantity of mouthwash solution used in rinsing, length of rinsing, and treatment frequency and period. CHX mouthwash solution had short-term effect on salivary MS. Most of studies evaluating CHX gel and varnish used a concentration of 1%. The 1% CHX gel showed a significant reduction through intensive treatment (3-4 daily applications over 2 days) or through daily application for 10 and 14 days. It cannot be asserted that 1% CHX varnish provides better results when applied intensively as compared to applications conducted at intervals of 1 or more months. Treatment using 1% CHX varnish displays large variations in the level and length of decreased MS levels. Despite variability in results, 40% CHX varnish has a greater effect on the period of decreased MS levels than does 1% CHX varnish. Studies did not show a statistically significant difference between the gel and the varnish. The effects of CHX treatment must be monitored, given sharp individual variability in response to this treatment.     

Short term effect of mechanical plaque control on salivary concentration of S. mutans and lactobacilli

Abstract — All visible plaque was professionally removed from teeth of 40 children who were highly infected with S. mutans and lactobacilli. Shortly before and after the removal of plaque the concentrations of those bacteria were assessed in saliva stimulated by chewing. S. mutans and lactobacilli correlated well at baseline but not after plaque elimination, e.g. more than 80% of children who were heavily infected with S. mutans could be identified by a lactobacillus test at baseline. After the elimination of plaque, the mean concentration of S. mutans dropped by 64% but lactobacilli remained unchanged. The results indicate that oral hygiene measures taken by the patient prior to sampling of saliva may mask the true concentration of salivary S. mutans and complicate the identification of high caries risk patients.