In vivo evaluation of the effect of essential oil-containing oral strips on salivary bacteria using the checkerboard method.

OBJECTIVE: The aim of this study was to evaluate the antimicrobial effect of essential oil-containing oral strips on different species of the oral microbiota. METHODOLOGY: Saliva samples were collected from 20 subjects with good oral health, diluted and plated onto blood agar medium. The subjects were asked to place the strip (Listerine PocketPaks) on the tongue allowing it to dissolve. After 30 minutes, new saliva samples were collected again and the plates with the samples were incubated under anaerobic conditions at 37 degrees C for seven days. Colony counts (CFU/mL) were determined for each sample. The colonies on the plates were washed with 1 mL of TE buffer, and the bacterial suspensions were processed for the identification of 24 species by DNA probes and the Checkerboard DNA-DNA hybridization method. Differences in total counts, prevalence, and levels of the species evaluated before and after placement of the strips were determined by Wilcoxon sign rank and Chi-square tests. RESULTS: A modest increase in the total bacterial number in saliva from 1.4 x 10(8) to 1.7 x 10(8) bacterial cells was observed 30 minutes after the strip placement, although this change was not significant (p = 0.632). Most of the species reduced in frequency and/or levels, including the pathogens A. actinomycetemcomitans, C. rectus, E. corrodens, Fusobacterium spp., P. intermedia, and S. noxia, as well as the beneficial species A. meyeri, A. georgia, A. gerencseriae, A. odontolyticus, and P. acnes after strip placement. In contrast, A. viscosus, P. melaninogenica, P. gingivalis, P. micros, Streptococcus spp., T. forsythensis, and V. parvula presented an increase in prevalence and/or levels. These changes were not statistically significant after adjusting for multiple comparisons (p > 0.0022). CONCLUSION: The use of the essential oil-containing oral strips resulted in a short-term small increase in the total number of salivary microorganisms. In addition, a not significant decrease of certain periodontopathogens, and an increase in species compatible with oral health were observed.

Microbiological response of localized sites with recurrent periodontitis in maintenance patients treated with tetracycline fibers.

BACKGROUND: Whether adjunctive tetracycline fibers can provide an additive effect to scaling and root planing in treating non-responsive sites in maintenance subjects is still controversial. Recolonization of the bacteria from untreated sites or from the extracrevicular region may explain the insignificant response to local therapy. The purpose of the present study was to evaluate the microbiological response of sites treated with tetracycline fibers combined with scaling and root planing. METHODS: The study was conducted in a split-mouth design. Thirty patients on maintenance therapy having at least 2 non-adjacent sites in separate quadrants with probing depths between 4 to 8 mm with bleeding on probing, or aspartate aminotransferase enzyme levels > 800 microIU in the gingival crevicular fluid, were treated with scaling and root planing plus tetracycline fibers or with scaling and root planing only. Subgingival plaque samples were collected at baseline, and 1, 3, and 6 months following treatment. A. actino-mycetemcomitans, C. rectus, B. forsythus, E. corrodens, F. nucleatum, P. gingivalis, and P. intermedia were detected by culture, immunofluorescence, or PCR technique. RESULTS: There was a reduction of total bacterial cell count, as well as of certain periodontal pathogens, following treatment. The prevalence of A. actinomycetemcomitans, B. forsythus, and P. gingivalis and the mean proportions of C. rectus, P. intermedia, F. nucleatum, and P. gingivalis decreased after therapy, but there was no statistically significant difference between the 2 treatment groups with respect to bacterial proportions or the number of positive sites. Besides, the pathogens could not be eliminated from the periodontal pocket, and recolonization of the pocket was noted at 3 months post-treatment. CONCLUSIONS: Bacteria located within the cheek, tongue mucosa, saliva, or untreated sites may contribute to reinfection of the pockets and explain the insignificant response to local tetracycline therapy.

The antimicrobial activity of essential oils and essential oil components towards oral bacteria.

A method for reproducibly determining minimal inhibitory concentrations and minimal bactericidal concentrations of plant extracts towards fastidiously and facultatively anaerobic oral bacteria, predicated upon measurements of optical densities in microtitre plate wells, was devised. The antimicrobial properties of some botanical oils were surveyed; of these, Australian tea tree oil, peppermint oil, and sage oil proved to be the most potent essential oils, whereas thymol and eugenol were potent essential oil components.

The antimicrobial activity of Prevention mouthrinse.

Prevention mouthrinse was designed to serve as a vital supplement to normal oral hygiene procedures. To determine the antimicrobial potency of this mouthrinse, minimal inhibitory concentrations (MICs), bactericidal kinetics, and short-term exposure studies were conducted. A spectrum of oral microorganisms was employed in this investigation: Streptococcus sanguis, Streptococcus anginosus, Streptococcus mutans, Actinomyces viscosus, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Eikenella corrodens, Porphyromonas gingivalis, Serratia marcescens and Candida albicans. Microorganisms were cultured in standard enriched media and under appropriate atmospheric conditions. Inhibition assays were conducted in tubes, with each mouthrinse dilution assayed in triplicate. MIC determinations revealed that all of the microorganisms studied were highly susceptible to Prevention mouthrinse, with MICs ranging from 16-fold to 128-fold dilutions. Bactericidal kinetics assays showed rapid killing of the test organisms in the presence of the mouthrinse. Brief (5-minute) exposure of S. mutans to 8-fold diluted mouthrinse resulted in a substantial delay in growth. Under the constraints of this type of study, Prevention mouthrinse exhibited potent antimicrobial activity against all of the microorganisms studied. We support the notion that Prevention mouthrinse may be a valuable supplement to normal oral hygiene procedures. A 6-month clinical trial assessing the in vivo efficacy of Prevention mouthrinse is currently being conducted.

Multicenter evaluation of tetracycline fiber therapy. III. Microbiological response.

In a multicenter study of the effects of tetracycline (TC) fiber therapy, subgingival plaque samples were tested for 6 probable periodontal pathogens by DNA probe analysis. Levels of Actinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas (Bacteroides) gingivalis, Prevotella intermedia (Bacteroides intermedius), and Wolinella recta were quantitatively determined in samples taken at baseline, and immediately after TC fiber removal, control fiber removal, and scaling and root planing. At untreated sites, samples were taken at baseline and 10 d later. Specificity of the DNA probe method was evaluated by testing the hybridization to 83 reference cultures. Interaction of the F. nucleatum probe with Fusobacterium periodonticum, and of the W. recta probe with Wolinella curva were the only cross-hybridizations noted. Species were detected at an average sensitivity of 2.9 x 10(4) organisms per sample. Approximately 70% of sites were initially infected with P. gingivalis and F. nucleatum; 50% with P. intermedia and E. corrodens; infections with W. recta and A. actinomycetemcomitans were less common (36% and 11% respectively). The average numbers of organisms found in the plaque samples were highest for F. nucleatum, P. gingivalis, and P. intermedia (ca. 10(6)). E. corrodens, W. recta, and A. actinomycetemcomitans occurred at 10-fold lower levels. Bacterial numbers and proportions of species in subgingival sites from the five centers did not differ appreciably. Both TC fiber therapy and scaling decreased the number of sites infected with all the monitored species. The bacterial composition at untreated sites and at sites where control fibers were placed was not significantly altered. The percentage reduction of the number of sites with detectable infection varied with each species: from 86% with W. recta to approximately 40% with P. gingivalis. Significant reduction of pocket depth and bleeding occurred at TC fiber-treated sites infected with each of the species. Significant attachment level gain occurred only at sites initially infected with P. gingivalis and treated with TC fibers.

Tetracycline fiber therapy monitored by DNA probe and cultural methods.

Oligonucleotide DNA probe and selective cultural methods were compared in their ability to monitor 6 putative periodontal pathogens in a study evaluating local tetracycline fiber therapy. Subgingival plaque was sampled from 4 sites in each of 20 subjects. Samples were taken before and after therapy from sites assigned to the following test groups: tetracycline (TC) fiber, scaling and root planing, control fiber, and untreated. Each sample was analyzed by both DNA probe and cultural methods. Total anaerobic cultivable counts, Porphyromonas (Bacteroides) gingivalis and Prevotella intermedia (Bacteroides intermedius) were enumerated on nonselective blood agar. Actinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum and Wolinella recta were isolated on selective media. TC fiber therapy and scaling reduced total cultivable counts from an initial value of 1 x 10(7) to approximately 2 x 10(5) following therapy. Total counts at untreated sites and at sites with control fibers did not change from baseline. A. actinomycetemcomitans and E. corrodens were detected more frequently by the cultural method; the other monitored species were detected more frequently by DNA probes than by the cultural methods. Agreements between methods were: 77.2% for A. actinomycetemcomitans; 72.2% for P. intermedia; 75.6% for E. corrodens; 39.4% for F. nucleatum; 35.6% for P. gingivalis; and 68.9% for W. recta. Limitations of the selective cultural methods used probably contributed to the discrepancies for P. gingivalis and F. nucleatum. DNA probe and cultural methods indicated comparable levels of suppression of the monitored species following TC fiber therapy and scaling. The microbiota of control fiber and untreated sites did not appear to be significantly altered by either method.