A preliminary clinical trial using flowable glass-ionomer cement as a liner in proximal-ART restorations: the operator effect

Objectives: This in vivo study was carried out to assess the influence of the operator experience on the survival rate of proximal-ART restorations using a two-layer technique to insert the glass-ionomer cement (GIC). Study Design: Forty five proximal cavities in primary molars were restored in a school setting according to the ART technique. The cavities were restored by two operators with Ketac Molar Easymix, and received a flowable layer of GIC prior to a second GIC layer with a regular consistency. The operators had different clinical experiences with ART (no experience or two years of experience), but both completed a one-week training to perform the restorations and the GIC mixing in this study. Results: After a 12-month follow-up, 74% of the restorations survived; the main reason for failure was bulk fracture or total loss of the restoration.There was no operator influence (log-rank test p=0.2) Conclusion: The results encourage future well designed controlled clinical trials using the two-layer technique for insertion of GIC in proximal-ART restorations, after training the operators

The Influence of Oral Bacteria on Epithelial Cell Migration In Vitro

Oral ulcerations often arise as a side effect from chemo- and radiation therapy. In a previous clinical study, Porphyromonas gingivalis was identified as a positive predictor for oral ulcerations after hematopoetic stem cell transplantation, possibly incriminating P. gingivalis in delayed healing of the ulcerations. Therefore, it was tested whether P. gingivalis and its secreted products could inhibit the migration of oral epithelial cells in an in vitro scratch assay. To compare, the oral bacteria Prevotella nigrescens, Prevotella intermedia, Tannerella forsythia, and Streptococcus mitis were included. A standardized scratch was made in a confluent layer of human oral epithelial cells. The epithelial cells were challenged with bacterial cells and with medium containing secretions of these bacteria. Closure of the scratch was measured after 17 h using a phase contrast microscope. P. gingivalis, P. nigrescens, and secretions of P. gingivalis strongly inhibited cell migration. A challenge with 1000 heat-killed bacteria versus 1 epithelial cell resulted in a relative closure of the scratch of 25% for P. gingivalis and 20% for P. nigrescens. Weaker inhibitory effects were found for the other bacteria. The results confirmed our hypothesis that the oral bacteria may be involved in delayed wound healing

Genetic Loci Associated With Fluoride Resistance in Streptococcus mutans

The prolonged exposure of the cariogenic bacterial species Streptococcus mutans to high concentrations of fluoride leads to the development of fluoride resistance in this species. Previous studies confirmed the involvement of a mutation in a single chromosomal region in the occurrence of fluoride resistance. The involvement of multiple genomic mutations has not been verified. The aim of this study is to identify multiple genetic loci associated with fluoride resistance in S. mutans. The previously published whole genome sequences of two fluoride-resistant S. mutans strains (UA159-FR and C180-2FR) and their corresponding wild-type strains (UA159 and C180-2) were analyzed to locate shared chromosomal mutations in fluoride-resistant strains. Both fluoride-resistant strains were isolated in laboratory by culturing their mother strains in media with high concentrations of fluoride. The corresponding gene expression and enzyme activities were accordingly validated. Mutations were identified in two glycolytic enzymes, namely pyruvate kinase and enolase. Pyruvate kinase was deactivated in fluoride-resistant strain C180-2FR. Enolase was less inhibited by fluoride in fluoride-resistant strain UA159-FR than in its wild-type strain. Mutations in the promoter mutp constitutively increased the promoter activity and up-regulated the expression of the downstream fluoride antiporters in fluoride-resistant strains. Mutations in the intergenic region glpFp led to lower expression of glpF, encoding a glycerol uptake facilitator protein, in fluoride-resistant strains than in wild-type strains. Our results revealed that there is overlap of chromosomal regions with mutations among different fluoride-resistant S. mutans strains. They provide novel candidates for the study of the mechanisms of fluoride resistance

European Organization for Caries Research Workshop: Methodology for Determination of Potentially Available Fluoride in Toothpastes

Toothpastes are the most universally accepted form of fluoride delivery for caries prevention. To provide anti-caries benefits, they must be able to release fluoride during the time of tooth brushing or post brushing into the oral cavity. However, there is no standard accepted procedure to measure how much fluoride in a toothpaste may be (bio) available for release. The European Organization for Caries Research proposed and supported a workshop with experts in fluoride analysis in toothpastes and representatives from industry. The objective of the workshop was to discuss issues surrounding fluoride analysis in toothpaste and reach consensus on terminology and best practices, wherever the available evidence allowed it. Participants received a background paper and heard presentations followed by structured discussion to define the problem. The group also reviewed evidence on the validity, reliability and feasibility of each technique (namely chromatography and fluoride electroanalysis) and discussed their strengths and limitations. Participants were able to reach a consensus on terminology and were also able to identify and summarize the advantages and disadvantages of each technique. However, they agreed that most currently available methods were developed for regulatory agencies several decades ago, utilizing the best available data from clinical trials then, but require to be updated. They also agreed that although significant advances to our understanding of the mechanism of action of fluoride in toothpaste have been achieved over the past 4 decades, this clearly is an extraordinarily complex subject and more work remains to be done

Chapter 7: Sugar and Dental Caries

Sugar is added to food for a multitude of functions: fermentation, preservation, physical and chemical, and also to satisfy the consumer's preference for sweetness. Unfortunately, sugar consumption is also a main aetiological factor for dental caries. The relationship between sugar and caries was established in the latter half of the 19th century. Many factors influence this relationship: the availability of sugar for bacterial digestion, the presence of acidogenic bacteria in the plaque on teeth, and the ability of fluoride and saliva to counteract bacteria and acids. The importance of the frequency of administering sugars over the amount has been demonstrated in various studies in humans. Through guidelines, world and national health organizations advocate the reduction of sugar consumption to below 10E% (daily dietary energy percentage consumption per capita), but voluntary implementation on an individual basis is difficult for many, and maybe more compulsory strategies that aim to reduce both the amount and frequency of sugar intake are needed

An application of the Health Action Process Approach model to oral hygiene behaviour and dental plaque in adolescents with fixed orthodontic appliances

Background. The Health Action Process Approach (HAPA) model addresses health behaviours, but it has never been applied to model adolescents’ oral hygiene behaviour during fixed orthodontic treatment. Aim. This study aimed to apply the HAPA model to explain adolescents’ oral hygiene behaviour and dental plaque during orthodontic treatment with fixed appliances. Methods. In this cross-sectional study, 116 adolescents with fixed appliances from an orthodontic clinic situated in Almere (the Netherlands) completed a questionnaire assessing oral health behaviours and the psychosocial factors of the HAPA model. Linear regression analyses were performed to examine the factors associated with dental plaque, toothbrushing, and the use of a proxy brush. Results. Stepwise regression analysis showed that lower amounts of plaque were significantly associated with higher frequency of the use of a proxy brush (R2 = 45%), higher intention of the use of a proxy brush (R2 = 5%), female gender (R2 = 2%), and older age (R2 = 2%). The multiple regression analyses revealed that higher action self-efficacy, intention, maintenance self-efficacy, and a higher education were significantly associated with the use of a proxy brush (R2 = 45%). Conclusion. Decreased levels of dental plaque are mainly associated with increased use of a proxy brush that is subsequently associated with a higher intention and self-efficacy to use the proxy brush

A Mobile App (WhiteTeeth) to Promote Good Oral Health Behavior Among Dutch Adolescents with Fixed Orthodontic Appliances: Intervention Mapping Approach

De verdediging hiervan was op 26 september. Background: The insertion of fixed orthodontic appliances increases the risk of dental caries, particularly in adolescents. Caries can be prevented through good oral health behavior. To support adolescents with fixed orthodontic appliances and for promoting oral health behavior, we developed a theory- and evidence-based mHealth program, the WhiteTeeth app. Objective: The objective of our paper was to describe the systematic development and content of the WhiteTeeth app. Methods: For systematic development of the program, we used the intervention mapping (IM) approach. In this paper, we present the results of applying the first 5 steps of IM to the design of an mHealth program: (1) identifying target behaviors and determinants through problem analysis, including a literature search, a survey study, and semistructured interviews, to explore adolescent oral health behavior during orthodontic therapy; (2) defining program outcomes and objectives; (3) selecting theoretical methods and translating them into practical strategies for the program design; (4) producing the program, including a pilot test with 28 adolescents testing the acceptability and usability of the WhiteTeeth app; and (5) planning implementation and adoption. Auteurs: Scheerman, J.F.M., van Empelen, P., van Loveren, C., & van Meijel, B. (2018

A mobile app (Whiteteeth) to promote good oral health behavior among dutch adolescents with fixed orthodontic appliances: Intervention mapping approach

Background: The insertion of fixed orthodontic appliances increases the risk of dental caries, particularly in adolescents. Caries can be prevented through good oral health behavior. To support adolescents with fixed orthodontic appliances and for promoting oral health behavior, we developed a theory-and evidence-based mHealth program, the WhiteTeeth app. Objective: The objective of our paper was to describe the systematic development and content of the WhiteTeeth app. Methods: For systematic development of the program, we used the intervention mapping (IM) approach. In this paper, we present the results of applying the first 5 steps of IM to the design of an mHealth program: (1) identifying target behaviors and determinants through problem analysis, including a literature search, a survey study, and semistructured interviews, to explore adolescent oral health behavior during orthodontic therapy; (2) defining program outcomes and objectives; (3) selecting theoretical methods and translating them into practical strategies for the program design; (4) producing the program, including a pilot test with 28 adolescents testing the acceptability and usability of the WhiteTeeth app; and (5) planning implementation and adoption. Results: On the basis of our literature search, we identified fluoride use and control of dental plaque levels (eg, tooth brushing and proxy brush usage) as target behaviors for preventing caries. Next, we identified important and changeable determinants of oral health behavior that fitted the theoretical concepts of the Health Action Process Approach (HAPA) theory. The HAPA theory, the self-regulation theory, and the results of the semistructured interviews were used to define the program objectives, that is, the performance and change objectives. After defining the objectives, we identified multiple behavior change techniques that could be used to achieve these objectives, such as providing oral health information and feedback, prompting self-monitoring, coaching of set actions and coping plans, and sending reminders. We translated these methods into practical strategies, such as videos and a brushing timer. Next, we combined these strategies into a single program resulting in the WhiteTeeth app (which is available on both iTunes and Google Play stores as “Witgebit”). Adolescents with fixed orthodontic appliances and dental professionals were included in the development process to increase the success of implementation. The pilot test revealed that the app users appreciated and liked the app. The WhiteTeeth app can be integrated into current orthodontic care. Conclusions: IM allowed us to identify multiple techniques that have been shown to be the most effective in initiating behavior change, but have not yet been incorporated into existing orthodontic apps. The WhiteTeeth app contains all these techniques, which makes it a unique and promising home-based app for promoting oral health in adolescents with fixed orthodontic appliances

Health action process approach in oral health behaviour: Target interventions, constructs and groups—A systematic review

Objective: The aim of this study was to systematically map the Health Action Process Approach (HAPA)-based interventions in dentistry in relation to the type of intervention, the target groups and the constructs of the HAPA model that are used in the study and to assess the clinical relevance of the studies. Methods: A search in the databases of the National Library of Medicine (MEDLINE-PubMed), PsychINFO and Cochrane-CENTRAL was conducted. A quality assessment to estimate the risk of bias and a qualitative descriptive analysis were performed. The overall gathered evidence was graded. Results: Ten randomized controlled trials and three observational studies thus in total 13 studies were included. Flossing was the targeted behaviour in ten studies. The target groups consisted of students, adolescents and dental patients. Overall, all nine HAPA constructs were used, but only one study used all HAPA constructs. Six studies presented the used behavioural change techniques according to the BCT taxonomy. Based on the number of the used constructs, only two studies were classified as HAPA intervention studies. The most frequently used constructs were action control as an intervention and behaviour as an outcome measure. The overall evidence was graded with moderate certainty. Conclusion: In the majority of the studies, the targeted intervention was flossing and the population consisted of students, adolescents and dental patients. All studies used only a selection of the HAPA constructs. Therefore, only a minority of the studies can be considered real HAPA intervention studies