The samples of dental deposit plaque collected from 30 people in the faculty of Natural Science were stained by Gram technique. A bacterial prosperious component was detected including Gram (+) cocci, Gram (-) cocci, red and thin cell, red and long cell, straight and curved Gram (-) cells, thin spinal cells … Microorganism population on the deposit plaque under the gun includes bacteria, cocci, and spirochaetes. 3 genera were determined including Streptococcus, Lactobacillus and Actinomyces, with a highest incidence of Streptococcus. The representative genus has the characteristic similar to Streptococcus mutans and it seems that it plays an important role leading to caries
Dental Plaque ; Bacteria ; Dental Care

BACKGROUND AND OBJECTIVE: The role of dental plaque as the etiology of caries and periodontal diseases has long been established. Therefore, plaque control is central to the prevention and management of these oral diseases. Among the different means of self-performed plaque control, brushing is the most essential. Moreover, toothpaste is a common adjunct during tooth brushing, as its abrasive contents are believed to enhance plaque removal. This study aimed to compare the effectiveness of plaque removal when brushing with a sodium bicarbonate abrasive-containing toothpaste, compared to brushing using an abrasive-free toothpaste.

METHODS: Twelve students from the University of the Philippines College of Dentistry participated in the study. The subjects discontinued all oral hygiene measures for a minimum of 48 hours. Using the Modified Bass technique, they performed tooth brushing for two minutes, using either an abrasive-free or abrasive containing toothpaste. Toothpaste allocation was randomized via fishbowl method. Pre-brushing and post brushing plaque scores were recorded using the Turesky modification of Quigley-Hein plaque index. A washout period of 11 days was implemented before crossover to the second round, wherein employed toothpastes were switched. The difference in plaque reduction between the two kinds of toothpaste was analyzed using Wilcoxon signed rank test.

RESULTS AND CONCLUSION: Overall plaque reductions were 75% for the abrasive-free toothpaste and 73% for the abrasive-containing toothpaste. The difference between the toothpaste was statistically insignificant (p=0.48). Therefore, based on the study, brushing with a sodium bicarbonate abrasive-containing toothpaste resulted in similar levels of plaque removal, compared to brushing with an abrasive-free toothpaste. There is insufficient evidence that abrasives in toothpaste result in more effective dental plaque removal. 

OBJECTIVES: The aim of this study was to compare Plaque Percent Index (PPI), calculated by Patient Hygiene Performance Index (PHPI), Rustogi's modification of the Navy Plaque Index (RMNPI), and the Quigley & Hein Plaque Index (QHPI), with visual assessment. METHODS: Ninety-six subjects, aged between 30–65 years, were examined; twenty subjects were included in the final analysis. The subjects' teeth were stained and photographed. Dental coloring and intraoral camera photography were performed by a single examiner. The oral images obtained were analyzed using Image J to measure the area of dental plaque. The values of PHPI, RMNPI, and QHPI were calculated twice. Statistical analyses were performed using descriptive statistics, chi-square test, and Pearson's correlation coefficient. RESULTS: The results of the correlation analyses of PPI with PHPI, QHPI, and RMNPI were as follows: for PHPI, the correlation coefficient (r)=0.584; for QHPI, r=0.689; and for RMNPI, r=0.729. Further, the kappa indices of PHPI, QHPI, and RMNPI were 0.810, 0.677, and 0.590 respectively. CONCLUSIONS: Among RMNPI, QHPI, and PHPI dental plaque indices, RMNPI and QHPI showed a high degree of correlation with the actual stained dental plaque area; on the other hand, PHPI showed the highest kappa index.
Dental Plaque Index* ; Dental Plaque* ; Hand ; Humans ; Hygiene ; Photography ; Tooth

OBJECTIVETo compare the periodontal indices and Porphyromonas gingivalis (P. gingivalis) between the use of self-ligating brackets and conventional brackets.

METHODSThirty patients were divided into 2 groups(n=15). Self-ligating brackets were used in the experimental group. Conventional brackets were used in the control group. Clinical periodontal indices, including plaque index (PLI), gingival index (GI) and probing depth (PD) of observed teeth were examined at three different time points: Before orthodontic treatment, the first month after treatment and the third month after treatment. Subgingival plaques were collected simultaneously at each time point. The number of total bacteria and P. gingivalis in each sample were detectd and quantitated by real-time quantitative polymerase chain reaction, the percentage of P. gingivalis in total bacteria was obtained.

RESULTSBefore treatment, the periodontal indices and the percentage of P. gingivalis in total bacteria had no difference between the two groups (P>0.05). After 1 and 3 months respectively, the periodontal indices and the percentage of P. gingivalis in total bacteria increased with time (P<0.05) and were obviously lower than those of the control group (P<0.05).

CONCLUSIONCompared with conventional brackets, the self-ligating brackets are better for periodontal health. But it is adverse effect on oral health.

Dental plaque is structurally a kind of biofilm which contains a variety of micro-organisms. The interreaction of oral micro-organisms may affect the nature, forms, and toxicity of the dental plaque biofilm, as well as the localization and field planting of bacteria inside the biofilm. The signal transduction existed between the bacterium has an important effect on the formation and virulence of bacterial biofilm. This reviewing paper focuses on the latest research progress of human oral microbial community and dental plaque biofilm.
Bacteria ; Bacterial Adhesion ; Biofilms ; Dental Plaque ; Humans

The purpose of this study was to evaluate the effectiveness of gargling solution with 0.05% NaF and 10% Xylitol in orthodontic patients with fixed appliance. The sample consisted of 20 patients who were classified into an experimental group and a control group, 10 patients each. Experimental group was used experimental gargling solution and the control group was used with placebo solution. The results were as follows. 1. There were significant reduction in the number of S. mutans C.F.U. between pre and post 3 weeks(p<0.01), 9 weeks(p<0.05) in experimental group. 2. There were significant reduction in the ration of S. mutans C.F.U. to total C.F.U between pre and post 3, 6, 9 weeks(p<0.01) in experimental group. 3. S. mutans, which were reduced until 3 weeks, did not show significant change after 3, 6, 9 weeks. 4. S. mutans were strongly suppressed until 3 weeks after gargling solution with 0.05% NaF and 10% Xylitol.
Dental Plaque* ; Humans ; Streptococcus mutans* ; Streptococcus* ; Xylitol

OBJECTIVETo establish determination method of formic acid, lactic acid, acetic acid and succinic acid in dental plaque with high performance liquid chromatography (HPLC).

METHODSAfter the samples were centrifuged, 2 microL supernatant was transferred to a 1 mL centrifuge tube and diluted in water, then was determined with HPLC. The mixture of phosphate buffer and methanol (97:3) as mobile phase throughout the experiment. The determination of organic acid was performed on Phenomenex C18 column and at their maximum absorption wave.

RESULTSThe linear ranges of formic acid, lactic acid, acetic acid and succinic acid were 0.110-500, 0.049-500, 0.047-500, 0.084-500 microg/mL. The detection limits were 0.110, 0.049, 0.047, 0.084 microg/mL. The relative standard derivation were 9.5%, 7.9%, 4.3%, 4.2%. The average recoveries of samples were 82%-112%, 82%-102.5%, 90%-115%, 80%-110%.

CONCLUSIONThe method was simple, quick and adapt for analysis of organic acid in dental plaque.

PURPOSE: To test the plaque-removal efficacy of a single-tufted toothbrush on the posterior molars compared with a flat-trimmed toothbrush. METHODS: Forty-nine subjects were selected. Professional instruction and written brushing instructions were given. After thorough supra-gingival scaling and polishing, all subjects were asked to abstain from oral hygiene procedures for 24 hours prior to the first experiment. The subjects were randomized to a treatment sequence. The modified Quigley and Hein plaque index was recorded pre- and post-tooth brushing, at 6 surfaces of the posterior molars. After a wash-out period, all the remaining plaque was removed professionally. Twenty-four hours of brushing abstinence was again performed. The plaque index was recorded pre- and post-tooth brushing after the subjects were given the second toothbrush in the cross-over sequence. RESULTS: The percentage reductions in plaque scores achieved with the single-tufted brushes were significantly higher than those of the flat-trimmed brush at the maxillary buccal interproximal, marginal and mandibular lingual interproximal site. The other locations showed no significant difference. CONCLUSIONS: The results of the present study implied that the single-tufted brush could be an effective tool for the removal of plaque at some, but not all, sites of the posterior molars.
Dental Equipment ; Dental Plaque ; Molar ; Oral Hygiene ; Toothbrushing

OBJECTIVES: To compare the treatment effects of periodontal endoscope-assisted and traditional subgingival scaling on residual pockets. METHODS: A total of 13 patients with periodontitis from Dept. of Periodontics, West China Hospital of Stomatology, Sichuan University were recruited. After 4-6 weeks of initial treatment, the residual pockets with a probing depth (PD) of ≥4 mm and attachment loss (AL) of ≥4 mm and bleeding on probing were examined with traditional (control group) and periodontal endoscope-assisted subgingival scaling (endoscopy group) in a randomly controlled split-mouth design. At baseline and 6 weeks and 3 months after treatment, plaque index (PLI), PD, AL, and bleeding index (BI) were measured. Differences in these clinical parameters within and between groups and patient-reported outcomes were compared. RESULTS: A total of the 694 sites of 251 teeth were included in this trial. Both groups showed significant improvement in each periodontal parameters 6 weeks and 3 months after treatment ( CONCLUSIONS Periodontal endoscope-assisted subgingival scaling resulted in better effects than traditional subgingival scaling when the residual pockets were in a single-rooted tooth, with a PD of ≥5 mm but without vertical alveolar bone resorption and furcation involvement.
Dental Plaque Index ; Dental Scaling ; Endoscopes ; Humans ; Periodontitis/therapy*

Streptococcus mutans (S. mutans) is generally regarded as a major contributor to dental caries because of its ability to synthesize extracellular polysaccharides (EPS) that aid in the formation of plaque biofilm. The VicRKX system of S. mutans plays an important role in biofilm formation. The aim of this study was to investigate the effects of vicK gene on specific characteristics of EPS in S. mutans biofilm. We constructed single-species biofilms formed by different mutants of vicK gene. Production and distribution of EPS were detected through atomic force microscopy, scanning electron microscopy and confocal laser scanning microscopy. Microcosmic structures of EPS were analyzed by gel permeation chromatography and gas chromatography-mass spectrometry. Cariogenicity of the vicK mutant was assessed in a specific pathogen-free rat model. Transcriptional levels of cariogenicity-associated genes were confirmed by quantitative real-time polymerase chain reaction. The results showed that deletion of vicK gene suppressed biofilm formation as well as EPS production, and EPS were synthesized mostly around the cells. Molecular weight and monosaccharide components underwent evident alterations. Biofilms formed in vivo were sparse and contributed a decreased degree of caries. Moreover, expressional levels of genes related to EPS synthesis were down-regulated, except for gtfB. Our report demonstrates that vicK gene enhances biofilm formation and subsequent caries development. And this may due to its regulations on EPS metabolism, like synthesis or microcosmic features of EPS. This study suggests that vicK gene and EPS can be considered as promising targets to modulate dental caries.
Animals ; Biofilms ; Dental Caries ; Dental Plaque ; Rats ; Streptococcus mutans/genetics*