Cytogenetic damage induced by mouthrinses formulations in vivo and in vitro.

The aim of the present study was to comparatively evaluate DNA damage and cellular death in cells exposed to various commercially available mouthrinses: Listerine Cepacol, Plax alcohol free, Periogard, and Plax Whitening. A total of 75 volunteers were included in the search distributed into five groups containing 15 people each for in vivo study. Exfoliated buccal mucosa cells were collected immediately before mouthrinse exposure and after 2 weeks. Furthermore, blood samples were obtained from three healthy donors for in vitro study. The micronucleus test was used to evaluate mutagenicity and cytotoxicity in vivo. The single-cell gel (comet) assay was used to determine DNA damage in vitro. After 2 weeks exposure, Periogard showed 1.8% of micronucleated cells with significant statistical differences (p < 0.05) compared to before exposure (0.27%). Plax Whitening presented high tail moment value (4.5) when compared to negative control (0.6). The addition of all mouthrinses to cells incubated with methyl methanesulfonate did not alter the number of strand breaks in the genetic material. Listerine was able to reduce genetic damage induced by hydrogen peroxide because a decrease of tail moment was noticed. The results of the present study suggest that Periogard and Plax Whitening can induce genetic damage, whereas Listerine is an antioxidant agent. Since DNA damage is considered to be prime mechanism during chemical carcinogenesis, these data may be relevant in risk assessment for protecting human health and preventing carcinogenesis.

Properties of a new mouthrinse for patients receiving radiation therapy.

INTRODUCTION: Patients receiving radiation therapy due to oral cancer develop complications such as hyposalivation, mucositis, oral infections, dental hypersensitivity and caries. Mouthrinses can alleviate some of these problems. AIMS AND OBJECTIVES: To investigate the in vitro antimicrobial properties and cytotoxicity of an experimental mouthrinse. METHODS: The mouthrinse contained 30% hexylene glycol (glycerine), 7% potassium nitrate and 0.025% sodium fluoride. The minimal inhibitory concentration (MIC) of these ingredients and the mixture was determined for C. albicans, S. aureus and S. mutans over 24 hours at different concentrations. The MICs of two commercial mouthrinses, Corsodyl and Plax, were also determined using the same organisms. All mouthrinses were then tested to determine the percentage kill over 1, 2, and 3 minutes. RESULTS: The MICs for hexylene glycol were 10%, 30% and 10% for C. albicans, S. aureus and S. mutons respectively. Potassium nitrate and sodium fluoride had no antimicrobial effects. The MIC of Corsodyl was 0.016 mg/ml for all the test organisms. The MIC for Plax varied from 0.0002 mg/ml to 0.001 mg/ml. The kill rates for all mouthrinses were acceptable, with no statistical differences between them. The experimental mouthrinse was not toxic to human oesophageal SCC cells after 1 minute exposure. At the time of the experiment, the costs of a similar quantity of the experimental mouthrinse, Corsodyl and Plax were R5.24, R30.00 and R10.00 respectively. CONCLUSIONS: The experimental mouthrinse was cost-effective and proved to have an antimicrobial effect and could be used safely to alleviate oral infections, desensitize teeth, improve oral hygiene and control dental caries in cancer patients after radiation therapy.

Cytotoxicity evaluation of Persica mouthwash on cultured human and mouse cell lines in the presence and absence of fetal calf serum.

BACKGROUND AND AIMS: The effectiveness of an ideal antimicrobial agent depends on its ability to kill microbes while causing minimal toxicity to host cells. Several studies have been reported on the antimicrobial effects of chewing sticks (Salvadora persica) on oral bacteria. The purpose of this study was to evaluate the cytotoxic effects of Persica and chlorhexidine (CHX) mouthwashes on cultured human and mouse cell lines. MATERIALS AND METHODS: This was an experimental study. The toxic effects of four dilutions of Persica and CHX mouthwashes on KB, Saos-2, J744 A1, and gingival fibroblast cells were evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. The effect of fetal calf serum (FCS) components on the cytotoxicity of these mouthwashes was also investigated. STATISTICAL ANALYSIS: Analysis of variance and the Kruskal-Wallis test were used to evaluate the results. RESULTS: The results indicated that Persica , at concentrations higher than 0.1%, exerted a very significant cytotoxic effect on all the cell lines (P < or = 0.01). CHX, at a concentration of 0.001%, exerted toxic effects only on gingival fibroblasts; concentrations higher than 0.001% were required to produce significant cell death in the other cell lines. At all the concentrations under study, both Persica and CHX exerted significantly greater cytotoxic effects in the absence of FCS than in its presence (i.e., in control culture medium). The toxicities of both mouthwashes were attenuated in the presence of FCS (10%). CONCLUSION: Our results indicate that both Persica and CHX mouthwashes are toxic to macrophage, epithelial, fibroblast, and osteoblast cells in a concentration-dependent manner.

Effect of three commercial mouth rinses on cultured human gingival fibroblast: an in vitro study.

AIM: To examine the effect of three commercial mouth rinses (Hexidine 0.2%, Listerine Cool Mint, Betadine 1%) upon cultured human gingival fibroblast proliferation. MATERIALS AND METHODS: Human gingival fibroblasts were cultured and incubated in Dulbecco's Minimum Eagle's Medium containing Chlorhexidine, Listerine, Povidone-Iodine at varying concentrations (1%, 2%, 5%, 10%, 20% and 100% of the given solution) at 37 degrees C for 1, 5 and 15 min. Control cells received an equal volume of Dulbecco's Minimum Eagle's Medium without adding mouth rinses, for similar duration of exposure at 37 degrees C. Following incubation the media were removed, cells were washed twice with medium, supplemented with 10% Fetal Bovine Serum, and fibroblasts in the test and control group were allowed to recover in the same media for 24 h. RESULTS: In all the three groups, the proliferation inhibition was dependent on the concentration of solublized mouth rinses in the cell culture but independent of the duration of exposure to all three mouth rinses. The results showed that all three solutions were toxic to cultured human gingival fibroblasts, Chlorhexidine being the most cytotoxic. It was seen that at dilute concentrations (1% and 2% of given solutions) Listerine was more cytotoxic than Chlorhexidine and Povidone-Iodine. CONCLUSION: These results suggest that Chlorhexidine, Listerine and Povidone-Iodine are capable of inducing a dose-dependent reduction in cellular proliferation of fibroblasts. The results presented are interesting, but to know the clinical significance, further studies are needed.

Toxicity screening of mouthwashes in the pollen tube growth test: safety assessment of recommended dilutions.

This study investigated whether mouthwash dilutions, recommended by the manufacturers, may contribute to oral mucosa irritation. Twenty frequently used mouthwash brands were examined by the pollen tube growth test, an alternative in vitro method for assessment of the irritating potential of ingredients of cosmetic formulations. The test is based on the photometric quantification of pollen tube growth inhibition. This parameter is expressed by IC50 values that characterize the cytotoxic potential of a product. The IC50s clearly revealed that none of the tested mouthwashes should cause acute irritation if used in the recommended dilution. However, at least 4 of the mouthwashes evaluated in this study could probably irritate the oral mucosa acutely if used undiluted (original concentration).

Toxicity screening of mouthwashes in the pollen tube growth test: safety assessment of recommended dilutions

Este estudo investigou se soluções de bochecho nas diluições recomendadas pelos fabricantes podem contribuir para a irritação das mucosas orais. Vinte soluções de bochecho frequentemente utilizadas foram avaliadas por meio do análise do crescimento do tubo polínico. Este teste constitui um método alternativo in vitro para estimar o potencial irritante dos ingredientes de formulações cosméticas. O teste baseia-se numa medição fotométrica da inibição do crescimento de tubos polínicos. A inibição do crescimento é expressa por valores IC50 que caracterizam o potencial citotóxico de uma dada substância. Os valores de IC50 aqui apresentados demonstraram que nenhuma das soluções de bochecho estudadas deve causar irritação aguda das mucosas orais, desde que utilizadas nas diluições recomendadas pelo fabricante. No entanto, verificou-se que pelo menos quatro dos colutórios podem causar irritação aguda das mucosas orais ao serem utilizados na a forma concentrada.

Toxicity assessment of mouthwashes in the pollen tube growth test.

AIM: Mouthwashes are frequently used to treat oral discomfort, halitosis or superficial infections. Adverse effects of mouthwash use are recognized, e.g. mucosal peeling and stomatitis. In addition, mouthwashes have been accused of causing oral cancer. The aim of this study was to analyse the acute toxicity of mouthwashes in an in vitro testing system, the pollen tube growth test (PTG test). MATERIALS AND METHODS: Twenty mouthwash brands were prepared for study. The mouthwashes were added to suspensions of pollen of tobacco plants (Nicotiana sylvestris) that were collected during the early stages of anthesis. The inhibition of the pollen germination and pollen tube growth T(t) was measured photometrically from centrifuged supernatants of the Alcian blue-stained suspensions at a wavelength of 607 nm after 18 hours of incubation. The results were compared to inhibitions that resulted from other toxic substances. RESULTS: In the PTG-test, the acute toxicity of several mouthwashes exceeds the toxic effect of alcohol. Calculated IC50 values for the mouthwashes ranged from 49,326 +/- 4881 mg/l to 541 +/- 137 mg/l. CONCLUSION: Consumers should be informed about the number and concentrations of mouthwash ingredients and their toxic potential. These declarations would provide the basis for further testing the toxic effects of mouthwashes.

In vitro toxicity assessment of mouthwashes in the pollen tube growth test: first results.

Mouthwashes are widespread used to treat halitosis or minor oral infections. Adverse effects of mouthwashes were recognized, e.g. desquamation of the oral mucosa and stomatitis. The acute toxicity of mouthwashes was tested in an in vitro system, the pollen tube growth test (PTG-test). In the PTG-test the acute toxicity of mouthwashes exceeds the toxic effect of alcohol. Consumers should be informed about the number and amounts of mouthwash ingredients, and their toxic potential. These declarations would provide the basis for testing the carcinogenic effects of mouthwashes.