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Publications (4)7.2 Total impact

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    ABSTRACT: To evaluate the in vivo effect of chewing gum containing allyl isothiocyanate alone, and in combination with zinc salts on reduction of the level of volatile sulfur compounds responsible for oral malodor. 15 healthy volunteers between the ages of 20-50 chewed either an experimental gum or a placebo gum for 12 minutes. Their mouth air was analyzed for volatile sulfur compounds by a gas chromatograph at baseline, immediately after chewing, and at 60, 120 and 180 minutes after treatment. The study revealed that allyl isothiocyanate, a constituent of mustard seed extract, can effectively reduce the concentration of volatile sulfur compounds in mouth air. Chewing gum containing 0.1% zinc lactate and 0.01% of allyl isothiocyanate eliminated 89%, 55.5%, 48% and 24% of the total VSC concentration immediately after chewing and at 1, 2, and 3 hours after chewing, respectively.
    American journal of dentistry 08/2013; 26(4):180-4. · 1.06 Impact Factor
  • Minmin Tian, A Bryan Hanley, Michael W J Dodds
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    ABSTRACT: Oral malodor is a major social and psychological issue that affects general populations. Volatile sulfur compounds (VSCs), particularly hydrogen sulfide (H2S) and methyl mercaptan (CH3SH), are responsible for most oral malodor. The objectives for this study were to determine whether allyl isothiocyanate (AITC) at an organoleptically acceptable level can eliminate VSCs containing a free thiol moiety and further to elucidate the mechanism of action and reaction kinetics. The study revealed that gas chromatograph with a sulfur detector demonstrated a good linearity, high accuracy and sensitivity on analysis of VSCs. Zinc salts eliminate the headspace level of H2S but not CH3SH. AITC eliminates both H2S and CH3SH via a nucleophilic addition reaction. In addition, a chemical structure-activity relationship study revealed that the presence of unsaturated group on the side chain of the isothiocyanate accelerates the elimination of VSCs.
    Journal of Breath Research 03/2013; 7(2):026001. · 2.57 Impact Factor
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    ABSTRACT: This was a single-center, prospective, cross-sectional study stratified by age and gender with the objective of determining the relationship between gum chewing history, salivary flow, and dental caries severity in adults. We enrolled 191 subjects aged 18-65 years who underwent assessments for gum chewing history, unstimulated salivary flow rate, salivary pH, and caries severity. Unstimulated salivary flow rate tended to decline with increasing age (p = 0.04), and significant differences in unstimulated salivary flow rate were also found for males (0.58 ± 0.32 ml/min) versus females (0.48 ± 0.30 ml/min) (p = 0.02). Weekly gum chewing frequency was greater in younger subjects (p = 0.001) while no age group differences were noted in pieces per day or chewing duration. Gum chewing habits were similar in males and females. A multivariate model demonstrated that only days per week chewing gum (p < 0.001) and gender (p = 0.007) were predictive of unstimulated salivary flow rate (R(2) = 0.40). Mean caries severity scores, assessed via ICDAS II and DMFT, increased with age. In multivariate analysis, age was positively associated with ICDAS (p = 0.001) and days per week chewing gum was negatively associated with ICDAS (p = 0.004), indicating that caries severity increased with age, and that days of chewing provided an inverse effect, with increased days of chewing being associated with decreased severity of caries. Overall, a history of frequent gum chewing is associated with higher unstimulated salivary flow rate and lower caries severity.
    Caries Research 07/2012; 46(6):513-518. · 2.51 Impact Factor
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    ABSTRACT: To assess the oral debris removal efficacy of two commercial sugar-free chewing gums, based on a newly developed oral debris scoring system. A randomized, examiner-blinded, three-arm crossover study was conducted, with a 1-week washout period between the crossover phases. 42 healthy adults were randomly assigned to sugar-free stick gum (Wrigley's Extra Freshmint), sugar-free pellet gum (Wrigley's Extra Fruit) or no-gum chewing groups. Subjects consumed a single chocolate cookie, and were examined at baseline, and at 2-, 5-, and 10-minute time points with or without gum-chewing treatment. Primary outcome measures were oral debris scores on the occlusal surface, interproximal and gingival margin areas. The entire test procedure was repeated on two subsequent visits. The baseline conditions in the three groups did not differ significantly. Chewing either stick gum or pellet gum resulted in significantly lower oral debris scores (P < 0.0001) compared to the control (no-gum) treatment for all intraoral sites, while no significant difference was observed between the two chewing gum groups. Intra-examiner repeatability of the new scoring criteria was high throughout the study (Kappa > 0.90).
    American journal of dentistry 04/2012; 25(2):118-22. · 1.06 Impact Factor