变形链球菌和放线菌与根面龋关系的研究

目的 分析变形链球菌和放线菌与根面龋的关系。方法 用选择性培养基ＭＳ和ＢＹＳ对３０例根面龋中的变形链球菌、放线菌定量研究。结果 放线菌的检出率１００％,变形链球菌的检出率９３．３３％,放线菌在数量上（ＣＦＵ）占绝对优势,与变形链球菌数量相比有高度显著性差异,Ｐ〈０．０１。结论 支持放线菌是根面龋优势菌的观点。     

变形链球菌和放线菌与根面龋关系的研究

目的 :分析变形链球菌和放线菌与根面龋的关系。方法 :用选择性培养基MS和BYS对 30例根面龋中的变形链球菌、放线菌定量研究。结果 :放线菌的检出率 10 0 % ,变形链球菌的检出率 93.33% ,放线菌在数量上 (CFU)占绝对优势 ,与变形链球菌数量相比有高度显著性差异 ,P <0 .0 1。结论 :支持放线菌是根面龋优势菌的观点     

根面龋病灶微生物学研究

作者对13例根面龋患者病灶微生态系中的变形链球菌、乳酸杆菌、粘性放线菌进行定量研究。结果显示,变形链球菌在数量上占绝对优势,乳酸杆菌也较多,而粘性放线菌仅在1例中检出。故支持变形链球菌是根面龋和冠龋共同病原菌的观点。     

变形链球菌的环境应激反应

变形链球菌能适应不断变化的口腔环境并在其中生存，故而与龋病的发生密切相关。环境应激反应使变形链球菌的多种基因和蛋白质表达水平发生改变，涉及细菌的物质代谢、细胞修复及细胞信号传导系统等多方面。对环境应激反应时变形链球菌毒力因子表达变化的研究可更深入了解其致龋机制。本文就近年来对变链应激反应的分子生物学研究做一综述。     

老年人根面龋治疗的临床研究

根面龋是老年口腔疾患中最常见、危害较大的疾病之一,本文采用三种充填材料治疗并评价其疗效.结果显示:Dyract复合体与lonosit-Seal封闭剂疗效好,成功率高于FujiII玻璃离子水门汀.     

老年人根面龋的治疗体会

老年人由于牙龈萎缩和长期佩戴假牙压迫牙龈组织等原因，致结合上皮向根方移动而易使牙菌斑、食物残屑和微生物聚集，造成根面龋损，给老年患者造成进食和生活上的困难，降低了生活质量。据此，笔者将近几年临床老年人治疗所见介绍体会如下。     

变形链球菌和远缘链球菌致龋性的研究近况

变形链球菌和远缘链球菌是人类牙齿的主要致龋菌。近年研究表明两种细菌的生物学特性存在一定差异，远缘链球菌与龋病的活跃性密切相关，本文对两种细菌的流行病学、粘附机理、多的合成产酸酸耐酸进行了综述，为今后龋病病因学研究，抗龋疫的制备提供参考。     

变形链球菌的环境应激反应

变形链球菌能适应不断变化的口腔环境并在其中生存,故而与龋病的发生密切相关.环境应激反应使变形链球菌的多种基因和蛋白质表达水平发生改变,涉及细菌的物质代谢、细胞修复及细胞信号传导系统等多方面.对环境应激反应时变形链球菌毒力因子表达变化的研究可更深入了解其致龋机制.本文就近年来对变链应激反应的分子生物学研究做一综述.     

变形链球菌特异性单克隆抗体的临床初步应用

目的:分析2～4 岁儿童唾液变形链球菌水平和患龋状况的关系. 方法:选取84 名平均年龄3.8 岁的儿童进行口腔检查;采用变形链球菌特异性单克隆抗体技术检测受试儿童唾液中的变形链球菌水平,分析变形链球菌水平和患龋情况的关系;比较25 名儿童接受干预治疗前后单克隆抗体技术检测的唾液变形链球菌水平的变化. 结果:84 名受试儿童变形链球菌检出率为100%,平均密度为1.0×106/ml.25 名儿童治疗后变形链球菌水平为2×105/ml, 低于治疗前,有统计学差异(P<0.05). 结论:变形链球菌特异性单克隆抗体技术可有效观察唾液中变形链球菌水平和龋齿的变化关系,以及追踪高水平变形链球菌儿童的龋齿发展情况.     

变形链球菌体外耐酸能力的实验研究

目的 :探讨来自不同龋敏感者变形链球菌 (血清型c)临床分离株耐酸能力的差异。方法 :配制相同浓度的各变形链球菌临床分离株菌悬液 ,分别在不同pH浓度 (pH 4 .0～ 7.0 )的TPY液体培养基中培养相同时间后 ,用紫外分光光度计测定吸光度 ,比较细菌的生长情况。结果 :同一个体所带不同基因型变形链球菌菌株耐酸能力具有差异 ;高龋组个体定植的耐酸能力强的菌株所占比例显著高于无龋组 (P <0 .0 5 )。结论 :高龋组变形链球菌 (血清型c)临床株的高致龋力与其耐酸能力强密切相关。     

Pellicle and early dental plaque in periodontitis patients before and after surgical pocket elimination

Abstract Objective. Gingival inflammation may affect the composition of the dental pellicle and initial acquisition of bacteria, which in turn could affect the healing of the periodontal pocket. The aim of this study was to examine the dental pellicle and early supragingival biofilms in periodontitis patients with an established subgingival infiltrate before and after surgical pocket elimination. Materials and methods. Eleven patients with remaining pockets were selected. Samples were taken before and after surgical pocket elimination and after subsequent experimental gingivitis. Pellicle proteins were analyzed by SDS-PAGE, immunoblotting and image analysis and 4-h supragingival plaque by culturing. Results. The inflammatory status affected to a greater extent the concentration of plasma proteins than salivary proteins in the dental pellicle. The highest plasma protein concentrations were observed at remaining periodontal pockets where also the highest bacterial counts were found. The TVC was reduced on the gingival tooth surfaces (p < 0.05) after pocket elimination and increased slightly during experimental gingivitis. The finding of streptococci was highest on the incisal tooth surfaces and increased after surgery. Gram-negative anaerobes were sparse but seen more often before than after pocket elimination and on gingival than on incisal surfaces. Conclusions. This study suggests that increased amounts of plasma proteins in the pellicle formed in the presence of remaining periodontal pockets may foster the acquisition of bacteria, including proteolytic Gram-negative species. This, in turn, results in an increased de novo plaque formation rate.     

Proportions of Streptococcus mutans, lactobacilli and Actinomyces spp in root surface plaque

Abstract – The incidence of Streptococcus mutans, lactobacilli and Actinomyces was examined in root surface dental plaque from 24 subjects with root surface caries and in 24 subjects with exposed root surfaces as a consequence of periodontitis but without root surface caries. Plaque was collected from the most posterior teeth in each quadrant: in the caries group from carious lesions and in the periodontitis group from buccal root surfaces. There were significantly higher proportions of S. mutans and lactobacilli in dental plaque samples taken from subjects suffering from root surface caries than in samples from subjects without root surface caries. The level of the group A. viscosus/naeslundii in the periodontitis group was higher than that found in the root surface caries group, but the difference was not statistically significant.     

Proportions of Streptococcus mutans, lactobacilli and Actinomyces spp in root surface plaque

The incidence of Streptococcus mutans, lactobacilli and Actinomyces was examined in root surface dental plaque from 24 subjects with root surface caries and in 24 subjects with exposed root surfaces as a consequence of periodontitis but without root surface caries. Plaque was collected from the most posterior teeth in each quadrant: in the caries group from carious lesions and in the periodontitis group from buccal root surfaces. There were significantly higher proportions of S. mutans and lactobacilli in dental plaque samples taken from subjects suffering from root surface caries than in samples from subjects without root surface caries. The level of the group A. viscosus/naeslundii in the periodontitis group was higher than that found in the root surface caries group, but the difference was not statistically significant.     

基于高通量测序技术研究慢性牙周炎患者龈下刮治和根面平整术治疗前后龈下菌群的变化

目的 采用基于16S核糖体DNA(rDNA)的高通量测序技术,分析10例慢性牙周炎患者接受龈下刮治和根面平整术(SRP)治疗前后龈下菌斑多样性及相对丰度的变化,探讨应用微生物群落的构成变化作为牙周炎诊断及预后评估指标的可行性.方法 选择2014年3—9月在首都医科大学附属北京口腔医院牙周科就诊的10例慢性牙周炎患者作为研究对象,在SRP治疗前及治疗后3个月分别在研究对象的同一位点采集龈下菌斑样本,提取样本基因组DNA,采用Illumina Miseq平台测序,分析各组样本从门到种各水平的菌群分布及相对丰度.结果 在门水平上,共检测到16个菌门,有8个门的细菌在牙周龈下菌斑菌群结构中占主要地位(99%);在属水平上,共检测到128个不同菌属,SRP治疗后3个月坦纳菌属(Tannerella)的相对丰度较治疗前明显降低(P<0.05),纤毛菌属(Leptotrichia)和链球菌属(Streptococcus)的相对丰度较治疗前明显上升(P<0.05);在种水平上,6种牙周可疑致病菌被检出,SRP治疗后3个月福赛坦纳菌(Tannerella forsythia)和中间普氏菌(Prevotella intermedia)的相对丰度较治疗前明显减少(P<0.05).结论 慢性牙周炎患者龈下菌群具多样性,SRP治疗前后,牙周可疑致病菌的相对丰度降低,而有益菌的相对丰度升高,SRP治疗可以明显改变龈下菌群构成.     

Plaque fluoride and mutans streptococci in plaque and saliva before and after discontinuation of water fluoridation

Our aim was to compare plaque fluoride and the level of mutans streptococci in saliva and plaque before and 1 and 2 years after discontinuation of water fluoridation in Kuopio, Finland. For comparison, a low-fluoride community was included in the study. Pooled plaque and saliva were collected from a random sample of 12-year-olds in both communities ( n =139). Enumeration of mutans streptococci in plaque was made on MSB agar and the level of salivary mutans streptococci was measured using the Strip mutans® method. Fluoride was analyzed using a fluoride specific electrode. Caries, gingival status, fluoride varnish applications and self-reported oral health habits were recorded at baseline. Before discontinuation of fluoridation. the level of mutans streptococci in saliva was significantly lower in the fluoridated than in the non-fluoridated community. The difference in plaque mutans streptococci was not statistically significant. After discontinuation of water fluoridation, there was a significant shift towards elevated values of salivary mutans streptococci in the fluoridated community, but the level of mutans streptococci in plaque remained at the baseline level. There was no significant difference between the communities in the fluoride content of plaque either before or after discontinuation of fluoridation. From the background factors, only caries scores (higher in the non-fluoridated community) and oral hygiene (better in the non-fluoridated community) were significantly different between the communities.     

A new selective medium for Streptococcus mutans and the distribution of S. mutans and S. sobrinus and their serotypes in dental plaque

A new selective medium (MS-MUT) was developed for the isolation of Streptococcus mutans from clinical specimens. The average growth recovery of S. mutans on MS-MUT medium was 72.4% of that on MS medium. Growth of Streptococcus sobrinus was significantly inhibited on the medium with an average recovery of 0.034%. In 103 subjects, S. MUTANS was detected at 58.3, 75.0 and 95.7% in the dental plaque of caries-free (CF), caries-inactive (CI) and caries-active (CA) subjects, respectively. S. sobrinus was detected in 8.3, 13.6 and 38.3% of CF, CI and CA subjects, respectively. S. sobrinus alone was detected in only 4.3% of CA subjects. The subjects in whom neither S. mutans nor S. sobrinus were detected were 41.6% in CF and 25.0% in CI. The most predominant serotype was C with a 67% detection rate. S. sobrinus, serotypes D or G were usually found together with S. mutans.     

Improvement of plaque score after oral hygiene instruction in patients with periodontitis

The purpose of this study was to investigate the variations in oral hygiene conditions after oral hygiene instruction. We divided the patients with periodontitis into three groups according to the number of times oral hygiene instruction had to be given to achieve the O'Leary plaque control record (PCR) of 20%. The first group was those who achieved PCR 20% quickly (early achievement group). The second group was those who achieved PCR 20% gradually but slowly (slow achievement group). And the third group was those who showed no progress at all (non achievement group). Results showed that there were statistical differences among the average changes in PCR and residual plaque score (PS) of the teeth surfaces in each group. Especially the early achievement group were significantly superior to the other groups in improvement of PS of mandibular lingual surface with one oral hygiene instruction. We also have investigated differences in the probing depth, age and sex at initial treatment among these three groups. The average probing depth at initial treatment was significantly deeper in the non achievement group than in the early achievement groups, and there were more males than females in the early achievement and non achievement groups.     

The effect of plaque control after scaling and root planing on the subgingival microflora in human periodontitis

The aim of the present study was to evaluate the effect of a strict supragingival plaque control regimen on bacterial repopulation following scaling and root planing. 7 patients with moderate to severe inflammatory periodontal disease received a full-mouth scaling and subgingival curettage. Using a split-mouth design, 2 sites of opposite quadrants were submitted to professional supragingival plaque control 3 X a week while the contralateral sites served as controls. Clinical and bacterial examination were performed on days 7, 14, 28, 49, 56, 63 and 70 following therapy. All clinical parameters (P1I, GI, probing depth, attachment levels) showed significant improvement after scaling and root planing. Shifts in the subgingival bacterial population observed by dark field were also noticed following curettage: there was a decrease in the proportions of spirochetes and motile rods and an increase in that of coccoid cells. However, bacterial distribution tended to return to base line values towards the end of the observation period. No difference in the pattern of bacterial recolonization of the subgingival area could be detected between the sites under strict supragingival plaque control and the control sites.     

固定矫治器粘结前后牙齿颊面菌斑pH值和变形链球菌附着的改变

目的对固定矫治器粘结前后牙颊面菌斑pH值和变形链球菌附着量、比例进行研究,初步探讨固定矫治中菌斑微生态的变化。方法应用离子选择性微电极测定菌斑提取液的pH值,对变形链球菌和总厌氧菌进行培养,记数。结果固定矫治器粘结后牙面菌斑pH值有极显著的下降(p<0.001),粘结一周后下降了0.5,三周后下降了0.7。菌斑湿重在粘结后三周有显著增多(p<0.05)。变形链球菌附着量、比例有极显著的升高(p<0.001)。粘结后一周,变形链球菌的数目平均上升了8.85×1011CFU/g;粘结后三周,平均上升了4.20×1011CFU/g,比例增加了1.10％。结论固定矫治器粘结后颊面菌斑的致龋性增强,但并未转化为致龋性菌斑。固定正畸与龋易感性的关系有待进一步研究。