Yosuke Masuo

Effect of S-PRG Eluate on Biofilm Formation and Enzyme Activity of Oral Bacteria.

Recently, the antibacterial activity of a composite resin containing prereacted glass ionomer (S-PRG) filler was revealed. We examined the effect of an S-PRG eluate on various biologic activities of Streptococcus mutans and Porphyromonas gingivalis. Adherence ability of S. mutans was evaluated by microtiter plate assay; protease and gelatinase activities of P. gingivalis were examined by synthetic substrate hydrolysis and gelatin film spot assay, respectively. Coaggregation of P. gingivalis with Fusobacterium nucleatum was also examined. S-PRG eluate was found to suppress streptococcal adherence. S-PRG eluate inhibited the protease and gelatinase activities of P. gingivalis and the coaggregation between P. gingivalis and F. nucleatum. These results indicate that S-PRG eluate suppresses streptococcal adherence and inhibits the protease and coaggregation activities of P. gingivalis. These findings may prompt research into novel strategies for preventing caries and periodontitis.

Lactobacillus salivarius WB21–containing tablets for the treatment of oral malodor: a double-blind, randomized, placebo-controlled crossover trial

OBJECTIVE This study evaluated the effect of probiotic intervention using lactobacilli on oral malodor. STUDY DESIGN We conducted a 14-day, double-blind, placebo-controlled, randomized crossover trial of tablets containing Lactobacillus salivarius WB21 (2.0 × 10(9) colony-forming units per day) or placebo taken orally by patients with oral malodor. RESULTS Organoleptic test scores significantly decreased in both the probiotic and placebo periods compared with the respective baseline scores (P < .001 and P = .002), and no difference was detected between periods. In contrast, the concentration of volatile sulfur compounds (VSCs) (P = .019) and the average probing pocket depth (P = .001) decreased significantly in the probiotic period compared with the placebo period. Bacterial quantitative analysis found significantly lower levels of ubiquitous bacteria (P = .003) and Fusobacterium nucleatum (P = .020) in the probiotic period. CONCLUSIONS These results indicated that daily oral consumption of tablets containing probiotic lactobacilli could help to control oral malodor and malodor-related factors.

Effects of S-PRG eluate on oral biofilm and oral malodor

OBJECTIVES This study evaluated the effects of a surface pre-reacted glass-ionomer (S-PRG) eluate on oral microbiota and dental biofilms in vitro, and on oral malodor and tongue bacterial loads clinically. STUDY DESIGN The effect of S-PRG eluate on the growth and survival of salivary bacteria was examined under both aerobic and anaerobic conditions; its ability to inhibit new biofilm formation and disrupt mature biofilms was also evaluated. The concentration of volatile sulfur compounds (VSCs) was measured using a portable sulfide monitor before and after rinsing with S-PRG eluate or distilled water. The number of bacteria on the tongue surface was calculated using a portable bacterial counter before and after tongue scraping with S-PRG eluate or distilled water. RESULTS No zone of inhibition was seen for S-PRG eluate against salivary microbiota under either aerobic or anaerobic conditions; however, treatment with ≥20% S-PRG eluate was sufficient to suppress biofilm formation relative to untreated controls. Mature biofilms were significantly disrupted following treatment with ≥60% S-PRG eluate relative to controls. Rinsing with S-PRG eluate significantly reduced the level of VSCs relative to baseline; this effect was not seen with distilled water alone. Waste fluids collected after oral rinsing with S-PRG eluate contained more bacteria than rinsing with distilled water alone. Finally, tongue scraping using S-PRG eluate was shown to significantly reduce the number of bacteria on the tongue surface. CONCLUSIONS S-PRG eluate inhibits biofilm formation and disrupts mature biofilms, although its antibacterial activity is limited. Oral rinsing and tongue cleaning with S-PRG eluate may reduce oral malodor by effectively removing oral bacteria from the oral cavity.

Relationship between the β-galactosidase activity in saliva and parameters associated with oral malodor.

Volatile sulfur compounds (VSCs) are produced by enzymes capable of transforming S-amino acids to corresponding sulfides. Protein degradation by periodontopathogens plays an important role in this process, and the proteolysis of glycoproteins depends on the initial removal of the carbohydrate side chains. In the present report, we tested the relationship between the β-galactosidase activity in saliva and parameters that influence oral malodor, including daily habits and oral conditions. The prevalence of periodontopathic bacteria was also examined. Forty-nine saliva samples were collected from halitosis patients. Patients were examined for breath odor and other associated parameters. Their breath odor was assessed using an organoleptic test, a portable sulfide monitor and gas chromatography. The presence of periodontopathic bacteria in the saliva was also examined. β-galactosidase activity was measured with the chromogenic substrates 5-bromo-4-chloro-3-indoyl-β-d-galactopyranoside and isopropyl-β-d-thiogalactopyranoside. β-galactosidase activity was positively correlated with malodor strength (organoleptic score, portable sulfide monitor score and VSC concentrations). Enzyme activity was also correlated with the degree of observable tongue coating. However, it showed no relationship with periodontal condition, saliva flow, tooth decay, unfitted restorations or the color of any tongue coating. While there was no relationship with Porphyromonas gingivalis and Treponema denticola, there was a negative correlation with Prevotella intermedia. These results indicate that β-galactosidase activity plays an important role in malodor production. Interestingly, the activity of this enzyme was not related to the presence of periodontopathic bacteria, which are the main malodor-producing organisms. The results obtained here may have been associated with physiologic halitosis, which is not necessarily associated with oral problems or with periodontopathic bacteria.

Enterococcus faecium WB2000 Inhibits Biofilm Formation by Oral Cariogenic Streptococci

This study investigated the inhibitory effect of probiotic Enterococcus faecium WB2000 on biofilm formation by cariogenic streptococci. The ability of E. faecium WB2000 and JCM5804 and Enterococcus faecalis JCM5803 to inhibit biofilm formation by seven laboratory oral streptococcal strains and 13 clinical mutans streptococcal strains was assayed. The Enterococcal strains inhibited biofilm formation in dual cultures with the mutans streptococcal strains Streptococcus mutans Xc and Streptococcus sobrinus JCM5176 (P < 0.05), but not with the noncariogenic streptococcal strains. Enterococcus faecium WB2000 inhibited biofilm formation by 90.0% (9/10) of the clinical S. mutans strains and 100% (3/3) of the clinical S. sobrinus strains. After culturing, the pH did not differ between single and dual cultures. The viable counts of floating mutans streptococci were lower in dual cultures with E. faecium WB2000 than in single cultures. Enterococcus faecium WB2000 acted as a probiotic bacterial inhibitor of cariogenic streptococcal biofilm formation.

Salivary β-galactosidase activity affects physiological oral malodour

OBJECTIVES Previous reports have associated salivary β-galactosidase activity with non-periodontopathic oral malodour. In this study, we investigated the localization of β-galactosidase and elucidated the relationship between its enzymatic activity and physiological oral malodour. STUDY DESIGN Fifty-six patients complaining of halitosis were separated into two groups: periodontally healthy and periodontitis. Saliva samples from the subjects were separated by centrifugation, and the level of β-galactosidase activity was measured in the supernatant, pellet lysate, and whole saliva using the chromogenic substrate o-nitrophenyl-β-d-galactopyranoside. The correlation of salivary β-galactosidase activity with breath odour and associated parameters was examined. RESULTS Similar levels of β-galactosidase activity were detected in the pellet lysate and whole saliva, but not in the saliva supernatant. Positive correlations were observed between the β-galactosidase activity in whole saliva and oral malodour levels in the periodontally healthy group, but not in the periodontitis group. In addition, the plaque index and tongue coating score were positively correlated with β-galactosidase activity in the periodontally healthy group. Overall, stimulated salivary flow and salivary pH were negatively correlated with enzyme activity. The amounts of total bacteria, Fusobacterium nucleatum, and Streptococcus salivarius were positively associated with β-galactosidase activity in the periodontally healthy group. Furthermore, the amounts of total bacteria and S. salivarius were positively associated with the amount of volatile sulphur compounds. CONCLUSIONS Our results indicate that β-galactosidase is located on the cell surface of oral bacteria derived from dental plaque and tongue coating, and it plays an important role in producing the malodour underlying physiological oral malodour.

A Case Report of Tooth Wear Associated with a Patient's Inappropriate Efforts to Reduce Oral Malodor Caused by Endodontic Lesion

Here, we report a case of severe tooth wear associated with a patients inappropriate efforts to reduce oral malodor. A 72-year-old male patient visited our breath clinic complaining of strong breath odor. Former dentists had performed periodontal treatments including scaling and root planing, but his oral malodor did not decrease. His own subsequent breath odor-reducing efforts included daily use of lemons and vinegar to reduce or mask the odor, eating and chewing hard foods to clean his teeth, and extensive tooth brushing with a hard-bristled toothbrush. Oral malodor was detected in our breath clinic by several tests, including an organoleptic test, portable sulphide monitor, and gas chromatography. Although patients oral hygiene and periodontal condition were not poor on presentation, his teeth showed heavy wear and hypersensitiving with an unfitted restoration on tooth 16. Radiographic examination of the tooth did not reveal endodontic lesion, but when the metal crown was removed, severe pus discharge and strong malodor were observed. When this was treated, his breath odor was improved. After dental treatment and oral hygiene instruction, no further tooth wear was observed; he was not concerned about breath odor thereafter.

A Case of Oral Malodor: Improving the Motivation of Patients by Use ofBacterial Examination

Here, we report a case of oral malodor that was diagnosed by bacterial examination. The patient (a 32-year-old female) visited our breath clinic because a family member advised her to do so. Strong oral malodor was detected by several tests including an organoleptic test, a portable sulfide monitor, and gas chromatography. She noticed her oral malodor, but her motivation toward treatment was low. Even after explaining the cause of halitosis and the importance of oral hygiene, her motivation did not improve. So we applied a bacterial examination, and explained the results in detail. She understood how oral bacteria had caused the oral malodor, and she tried to do tooth brushing better. After a basic periodontal treatment, her oral condition improved and the number of periodontopathic bacteria reduced. She continued with careful tooth brushing even after the periodontal treatment, and her breath odor remarkably decreased. This case report indicates the usefulness of bacterial examination for motivating patients to improve their oral hygiene.

Lactobacillus salivarius WB21–containing tablets for the treatment of oral malodor: a double-blind, randomized, placebo-controlled crossover trial—reply to letter

1. The enrollment period was from June 2010 to September 2011, and the intervention and observation period was from June 2010 to November 2011. 2. We intended to collect 100 registrants, but 82 patients were finally registered. We confirmed the power of the main outcome based on sample size (see the Discussion section). 3. The interquartile ranges (IQRs) for the data in the figures are provided in the text. 4. As described in the Methods section, the organoleptic test (OLT) scores were estimated by 2 evaluators, and the means of these scores were used in the analysis. Therefore, the x-axis is represented as 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5, and the yaxis is the number of participants. 5. As described in the Methods section, we confirmed that the degree of coincidence of the 3 evaluators always exceeded 75%. 6. As described in the Methods section, malodor was assessed at least 5 hours after eating, drinking, smoking, and brushing or rinsing of the mouth. 7. This was a crossover trial. Both periods contained 23 participants. Therefore, 26% (6 of 23) of the patients in the probiotic period and 13% (3 of 23) of the patients in the placebo period improved to an OLT score 1. 8. Thankyou foryour comments.However, oralmalodor is typically generated directly from the oral cavity. 9. As described in the Methods and Discussion sections, the period effect was present in the tongue coating score (TCS). Longer washout periods may be required to evaluate changes in the TCS. 10. See the Discussion section. 11. The statistical analysis for the study was performed by a statistician. The period effect was present only in the tongue coating score. The meaning of “mystify” is unclear. Do you mean that you want to see the raw data? 12. The data are shown as median and IQR of the average probing pocket depth (PPD) in Table II. The statistical analysis was performed using the Wilcoxon signed-rank test. 13. We have used the reference literature. Please see the details in our previous reports containing the reference literature.