Removal of oral debris and bacteria during supervised tooth brushing.

OBJECTIVE: To investigate foam generation during brushing, and the oral debris and bacteria removal efficacy of an experimental gel-to-foam dentifrice compared to a commercially-available dentifrice after brushing. METHODS: Thirty-four subjects participated in this blinded, crossover study. After a wash-out period prior to each session of product use, subjects reported to the site having abstained from oral hygiene, eating and drinking from 22:00 h on the evening prior to treatment visits. The subjects brushed with a weighed dose of assigned paste and were asked to expectorate their toothpaste slurry into a collection vessel at 30 and 60 seconds during supervised brushing. The expectorated foam was measured immediately, after which subjects rinsed with 10 ml of sterile water and expectorated into the same vessel. Samples were placed on ice and immediately transported to the laboratory for analysis. Bacteria (total anaerobes and VSC-producing bacteria) were enumerated using appropriate selective media. To calculate the amount of debris, a measured portion of the sample was deposited onto a pre-weighed dish and weighed. Dishes were dried thoroughly and weighed again after cooling. RESULTS: Use of the gel-to-foam dentifrice resulted in 105% greater foam volume compared with use of the control dentifrice (p < 0.0001). Further, the gel-to-foam dentifrice removed 15.77% more debris than the control dentifrice (p-value = 0.0342). There was greater removal of total anaerobes and VSC-producing bacteria by the gel-to-foam dentifrice versus the control dentifrice (p-value < 0.0001). CONCLUSION: Single use of a gel-to-foam dentifrice generated a greater volume of foam and removed a greater amount of oral debris and bacteria during brushing than a standard dentifrice.

Impact of different tongue cleaning methods on the bacterial load of the tongue dorsum.

OBJECTIVE: To assess the extent and duration of the effect of tongue cleaning procedures on bacterial load on the dorsal surface of the tongue. METHODS: 19 subjects participated in this blinded crossover study. Subjects abstained from oral hygiene, eating and drinking from 22:00 h the previous evening. Tongue samples were collected at baseline and within 15 minutes of one of three procedures: teeth brushing alone; teeth brushing plus tongue scraping; teeth brushing plus tongue cleaning using a high speed vacuum ejector and irrigation with 20 ml antibacterial mouthwash. Subjects then brushed twice daily for 3 days apart from the second group who additionally scraped their tongue twice daily. On day 4, baseline and post-treatment samples were collected as per day 1. Bacteria (total anaerobes, Gram-negative anaerobes, VSC-producing bacteria and Streptococcus saliuarius) were enumerated using appropriate selective media. RESULTS: The tongue dorsum was colonized by all 4 bacterial categories (log(10) 6-8 cfu/sample). For subjects who brushed their teeth only, there was a significant reduction from baseline for S. saliuarius only. In contrast, tooth brushing plus tongue scraping resulted in statistically significant reductions from baseline for all bacterial categories (range log(10) 0.11-0.40 cfu/sample). Highly statistically significant reductions (log(10) 1.11-1.96 cfu/sample) were observed for subjects who underwent thorough tongue cleaning with the saliva ejector/mouthwash. To determine longevity of treatment effects, baseline bacterial loads for days 1 and 4 were compared. Only daily tongue scraping resulted in statistical significant reduction in baseline microbial loads on day 4. CONCLUSION: While mechanical tongue cleaning with or without chemical intervention can reduce bacterial load on the tongue, this effect is transient, and regular tongue cleaning is required to provide a long lasting (overnight) reduction in bacterial numbers. Nevertheless, tongue cleaning is an oral hygiene procedure that is little practiced due to discomfort and/or lack of awareness on the part of dental professionals and their patients.

Control of oral malodour by dentifrices measured by gas chromatography.

OBJECTIVE: To evaluate the effect of toothpaste treatments on levels of oral volatile sulphur compounds (VSCs) measured by gas chromatography in two clinical studies. METHODS: These were blinded, randomised, controlled, crossover studies with 16 (study A) or 20 (study B) healthy volunteers between the ages of 19-54. Study A: breath samples were collected at baseline, immediately and lhr after brushing. Four dentifrices (Zinc A, Zinc B, commercially available triclosan dentifrice and zinc free control) were evaluated. Study B: breath samples were collected at baseline, immediately, 1, 2, 3 and 7 hours after treatment. Subjects consumed a light breakfast then provided an additional breath sample between baseline assessment and treatment. Two dentifrices (gel-to-foam and a commercially available triclosan dentrifrice) were evaluated. Breath samples were collected in syringes and analysed for VSCs (hydrogen sulphide, methyl mercaptan and Total VSCs) utilising gas chromatography (GC) with flame photometric detection. RESULTS: Study A: immediately after treatment, a statistically significant reduction in VSCs from baseline was observed for Zinc A product only. A statistically significant reduction in VSCs from baseline was observed after 1 hour for all products. Both zinc products exhibited a significantly greater reduction from baseline VSCs than Colgate Total and Control at all time points. Study B: a statistically significant reduction in VSCs from baseline was observed at all time points for both products. The gel-to-foam product exhibited significantly greater reduction from baseline Total VSC concentration than Colgate Total at all time points from 1 hour post-treatment. CONCLUSION: Control of oral malodour by toothpaste treatment, evaluated as VSC levels using GC, has been demonstrated. Zinc is effective at reducing VSCs and the efficacy of zinc is formulation dependent. A gel-to-foam dentifrice was more effective at reducing VSCs than Colgate Total up to 7 hours.

Topographic distribution of bacteria associated with oral malodour on the tongue.

OBJECTIVE: To investigate the topographic distribution of bacterial types and loads associated with mid-morning oral malodour on the tongue surface. DESIGN: Fifty subjects with good oral health and at least 20 natural uncrowned teeth were included. Samples were taken with sterile brushes from the dorsal anterior (DA), dorsal middle (DM), dorsal posterior (DP), dorsal posterior to the circumvallate papillae (DPCP), lateral posterior (LP) and ventral posterior (VP) tongue surfaces. Samples were cultured on appropriate media for anaerobic bacteria, aerobic bacteria, Gram-negative anaerobic bacteria, volatile sulphur compound (VSC)-producing bacteria and Streptococcus saliuarius. Malodour was assessed by trained judges on an intensity basis. RESULTS: The counts of all bacterial groups were consistently highest at the DPCP surface. Mean VSC-producing bacterial counts (colony forming units/brush x10(5)) were 1.45, 5.67, 32.52, 88.94, 6.46 and 0.33 at DA, DM, DP, DPCP, LP and VP surfaces, respectively. Anaerobic, Gram-negative and VSC counts at DPCP surfaces increased with malodour intensity, whereas aerobic and S. saliuarius counts decreased; however these differences were not statistically significant. CONCLUSION: It is concluded that the DPCP area consistently carries the highest load of bacteria capable of contributing to oral malodour. The study demonstrates that tongue surfaces not accessible to routine oral hygiene procedures can significantly contribute to oral malodour.