Melbourne Dental School - Research Publications
Permanent URI for this collection
Search Results
1 - 5 of 5
-
ItemThe prebiotic effect of CPP-ACP sugar-free chewing gum(ELSEVIER SCI LTD, 2019-12)OBJECTIVES: To determine if chewing gum containing casein phosphopeptide stabilised amorphous calcium phosphate (CPP-ACP) promoted an increase in the abundance of Streptococcus sanguinis and other species associated with dental health in supragingival plaque in a clinical study. MATERIALS AND METHODS: Nineteen participants were recruited for a three-leg cross-over, randomised, controlled clinical trial. Participants chewed a sugar-free gum with or without CPP-ACP six times daily for 20 min over two weeks. The study also involved no gum chewing (no gum) for the same two week period. Participants were randomly assigned to one of the test gums or no gum for each intervention period. Participants abstained from oral hygiene and had washout periods of two weeks between intervention periods. After each intervention period, supragingival plaque was collected and analysed for bacterial composition by sequencing the V4 variable region of the 16S rRNA gene. Data were analysed using a linear mixed model. RESULTS: The CPP-ACP gum intervention produced a significant (p < 0.01) increase in the proportions of S. sanguinis (112%), as well as the commensal species Rothia dentocariosa (127%), Corynebacterium durum (80%) and Streptococcus mitis (55%) when compared with the no gum intervention. All the species that were promoted by the CPP-ACP gum are known to possess one or both of the alkali-producing enzymes arginine deiminase and nitrate reductase. CONCLUSION: This clinical study demonstrated that chewing a sugar-free gum containing CPP-ACP promoted prebiosis by significantly increasing the proportion of S. sanguinis and other health-associated bacterial species in supragingival plaque. CLINICAL SIGNIFICANCE: Regular chewing of CPP-ACP sugar-free gum increases the proportions of health-associated commensal species in supragingival plaque to promote prebiosis and oral homeostasis.
-
ItemOral candidal carriage in asymptomatic patients(WILEY-BLACKWELL, 2016-06)BACKGROUND: Interest in the association between oral cancer risk and Candida-associated promotion of mucosal dysplasia continues. However, little is known of the presence and amount of oral yeast in the mouths of healthy patients without mucosal lesions. The purpose of this prospective cross-sectional clinical study was to ascertain the prevalence and degree of carriage of Candida in the oral cavities of a non-cancer population, with reference to a range of parameters affecting the oral environment. METHODS: Oral rinse samples were collected from a sample of 203 patients attending the Royal Dental Hospital of Melbourne and analysed for the presence and degree of colonization of yeast species that were phenotypically identified as albicans and non-albicans species. RESULTS: Oral yeast carriage was found in 98/203 patients (48.3%), and of these, 83 (84.7%) patients carried C. albicans. There was no statistical difference in carriage when comparing gender, age, or presence of a removable prosthesis. CONCLUSIONS: Both smoking and the presence of active carious lesions were found to be positively correlated with the carriage of oral Candida. Individuals who are current smokers are nearly seven times more likely to have oral Candida, and participants with high candidal colonization are more likely to be current smokers. Participants with active carious lesions were also more likely to carry oral Candida.
-
ItemAnticariogenic efficacy of a saliva biomimetic in head-and-neck cancer patients undergoing radiotherapy(WILEY, 2019-03)BACKGROUND: The aim of this study was to investigate the effect of treatment with the saliva biomimetic, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and SnF2 /NaF compared with SnF2 /NaF alone on coronal surface caries progression in head-and-neck cancer patients undergoing radiotherapy. METHODS: Twenty-four participants were randomized into two groups. Both groups used 0.4% SnF2 gel and a 0.32% NaF toothpaste; the test group also applied a crème containing 10% CPP-ACP three times daily while the control group used an identical crème without CPP-ACP (placebo). Resting saliva flow rate and saliva fluoride concentrations were determined. Caries status was assessed using ICDASII at baseline and 12-weeks postradiotherapy. Data were statistically analysed using a linear mixed effects model. RESULTS: Both groups showed significantly reduced resting saliva flow rate (P < 0.001) postradiotherapy. There were no significant differences in flow rates and fluoride concentration between groups. The CPP-ACP group exhibited a significant (P < 0.05) 51% reduction in coronal surface caries progression compared with the placebo group. CONCLUSION: Resting salivary flow rate was significantly reduced in head-and-neck cancer patients following radiotherapy and use of CPP-ACP with SnF2 /NaF significantly lowered caries progression compared with SnF2 /NaF alone.
-
ItemReducing Potentially Preventable Dental Hospitalizations of Young Children: A Community-Level Analysis.(SAGE Publications, 2018-07)An increasing number of Australians are being admitted to hospitals and day procedure centers to have dental treatment under a dental general anesthetic (DGA). Children younger than 2 y are having DGAs. These operations are costly and, although there have been improvements in safety, are not without risk. Most DGAs in children are to treat dental caries and have been defined as potentially preventable dental hospitalizations (PPDHs). This article reports on an analysis of the impact of access to community water fluoridation (CWF), availability of oral health professionals (OHPs), and socioeconomic status (SES) on PPDHs of 0- to 4-y-olds in 2012-2013 in Victoria, Australia. Data on these variables were obtained at the community (postcode) level. From the negative binomial multivariate analysis, each of the 3 independent variables was independently significantly associated with PPDHs at the postcode level. Children residing in postcodes without CWF on average had 59% higher rates than those with access (incident rate ratio [IRR], 1.59; P < 0.0001), children in postcodes with the lowest level of availability of OHPs had 65% higher rates than those with the highest access (IRR, 1.65; P < 0.0001), and children living in the most disadvantaged SES quintiles had 57% higher rates than children in the most advantaged quintiles (IRR, 1.57; P < 0.0001). There was a stepwise social gradient by SES quintile. In analysis of access to CWF and SES status, children without access to CWF had 86% higher PPDH rates than children with access (IRR, 1.86; P < 0.0001). In summary, no access to CWF, poor availability of OHPs, and lower SES status were independently associated with higher PPDH rates among 0- to 4-y-olds in Victoria at the postcode level. The study highlights the importance of considering 3 interacting factors-access to CWF, access to OHPs, and SES-in efforts to reduce PPDH rates in young children. Knowledge Transfer Statement: Extending access to water fluoridation, increasing the availability of dental services, and raising disadvantaged families' socioeconomic status are each likely to decrease the rate of dental general anesthetics in young children.
-
ItemNo Preview AvailablePolymicrobial nature of chronic oral disease(CSIRO publishing, 2015)Recent microbiome studies have shown that the human oral microbiome is composed of over 260 abundant bacterial species that predominantly live as polymicrobial biofilms accreted to the non-shedding hard surfaces of the teeth. In addition representatives of both Archaea and Fungi are found in the oral cavity and there is considerable colonisation of the soft tissues of the mouth. Most of these species are commensal and form complex biofilm communities that restrict the colonisation of the oral cavity by exogenous bacteria. Changes in the polymicrobial biofilm microenvironment such as those resulting from the effects of chronic inflammation for subgingival plaque, can lead to the emergence of opportunistic pathogens resulting in dysbiosis and the development of chronic diseases such as periodontitis in a susceptible host. The application of microbiomic studies to the analysis of these complex and dynamic communities in rigorously designed human clinical studies will provide valuable mechanistic insight into the bacterial succession and complex interactions involved in the development of dysbiosis and disease. value in exploring challenges for public policy given the broad societal, economic, and political implications of the present market predictions.