Svante Twetman

IT University of Copenhagen, København, Capital Region, Denmark

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Publications (160)183.5 Total impact

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    ABSTRACT: Background: To evaluate the effect of probiotic chewing tablets on early childhood caries development in preschool children living in a low socioeconomic multicultural area. Methods: The investigation employed a randomized double-blind placebo-controlled design. The study group consisted of 138 healthy 2-3-year-old children that were consecutively recruited after informed parental consent. After enrollment, they were randomized to a test or a placebo group. The parents of the test group were instructed to give their child one chewing tablet per day containing three strains of live probiotic bacteria (ProBiora3®) and the placebo group got identical tablets without bacteria. The duration was one year and the prevalence and increment of initial and manifest caries lesions was examined at baseline and follow-up. All parents were thoroughly instructed to brush the teeth of their off-springs twice daily with fluoride toothpaste. Results: The groups were balanced at baseline and the attrition rate was 20 %. Around 2/3 of the children in both groups reported an acceptable compliance. The caries increment (Δds) was significantly lower in the test group when compared with the placebo group, 0.2 vs. 0.8 (p < 0.05). The risk reduction was 0.47 (95 % CI 0.24-0.98) and the number needed to treat close to five. No differences were displayed between the groups concerning presence of visible plaque or bleeding-on-brushing. No side effects were reported. Conclusions: The results suggested that early childhood caries development could be reduced through administration of these probiotic chewing tablets as adjunct to daily use of fluoride toothpaste in preschool children. Further studies on a possible dose-response relationship seem justified TRIAL REGISTRATION: Identifier: NCT01720771 . First received: October 31, 2012.
    BMC Oral Health 09/2015; 15(1):112. DOI:10.1186/s12903-015-0096-5 · 1.13 Impact Factor
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    Svante Twetman ·
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    ABSTRACT: Background: The aim of this conference paper was to examine the evidence base for primary and secondary prevention of dental caries, erosions and dentin hypersensitivity through professional and self-care measures. Methods: A mapping of systematic reviews (SR) of literature was carried out in PubMed and the Cochrane library through April 2014 using established MeSH-terms and disease-related search words in various combinations. The search was restricted to SR's published in English or Scandinavian and all age groups were considered. The reference lists of the selected papers were hand-searched for additional review articles of potential interest. Meta-analyses, guidelines and treatment recommendations were considered only when SR's were lacking. In the event of updates or multiple systematic reviews covering the same topic, only the most recent article was included. No quality assessment of the systematic reviews was carried out. The quality of evidence was rated in four levels according to the GRADE scale. Results: In total, 39 SR were included. For primary caries prevention, the quality of evidence was high for the use of fluoride toothpaste (with and without triclosan) and moderate for fluoride varnish and fissure sealants. The quality of evidence for fluoride gel, fluoride mouth rinse, xylitol gums and silver diamine fluoride (SDF) was rated as low. For secondary caries prevention and caries arrest, only fluoride interventions and SDF proved consistent benefits, although the quality of evidence was low. Likewise, the GRADE score for preventing erosions located in the enamel with fluoride supplements was low. The quality of evidence for various professional and self-care methods to prevent and manage dentine hypersensitivity was very low. Conclusions: There are knowledge gaps in many domains of cariology and preventive dentistry that must be addressed and bridged through clinical research of good quality.
    BMC Oral Health 09/2015; 15(Suppl 1):S4. DOI:10.1186/1472-6831-15-S1-S4 · 1.13 Impact Factor
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    ABSTRACT: Background: This paper is a summary document of the Prevention in Practice Conference and Special Supplement of BMC Oral Health. It represents the consensus view of the presenters and captures the questions, comments and suggestions of the assembled audience. Methods: Using the prepared manuscripts for the conference, collected materials from scribes during the conference and additional resources collated in advance of the meeting, authors agreed on the summary document. Results: The Prevention in Practice conference aimed to collate information about which diseases could be prevented in practice, how diseases could be identified early enough to facilitate prevention, what evidence based therapies and treatments were available and how, given the collective evidence, could these be introduced in general dental practice within different reimbursement models. Conclusions: While examples of best practice were provided from both social care and insurance models it was clear that further work was required on both provider and payer side to ensure that evidence based prevention was both implemented properly but also reimbursed sufficiently. It is clear that savings can be made but these must not be overstated and that the use of effective skill mix would be key to realizing efficiencies. The evidence base for prevention of caries and periodontal disease has been available for many years, as have the tools and techniques to detect, diagnose and stage the diseases appropriately. Dentistry finds itself in a enviable position with respect to its ability to prevent, arrest and reverse much of the burden of disease, however, it is clear that the infrastructure within primary care must be changed, and practitioners and their teams appropriately supported to deliver this paradigm shift from a surgical to a medical model.
    09/2015; 15:S12. DOI:10.1186/1472-6831-15-S1-S12
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    ABSTRACT: Elderly individuals suffering from subnormal saliva secretion combined with inadequate oral hygiene may develop rampant caries and caries in parts of the dentition not normally affected by caries if preventive measures are not undertaken. Such measures include elevating fluoride levels at the saliva/biofilm/tooth interface. To analyse whole-saliva fluoride levels and mineral saturation indices during different fluoride toothpaste regimens in home-living elderly. Whole saliva was collected from 27 subjects (7 males and 20 females, mean age 73.5 ± 6.1 years) at ten time points covering the whole day during five 2-week periods. During the first period, participants used their normal toothpaste without instructions (baseline). This was followed by TP1: 1,450-ppm NaF toothpaste; TP2: 1,450-ppm monofluorophosphate (MFP) toothpaste with addition of calcium; TP3: 5,000-ppm NaF toothpaste, and TP4: the same toothpaste with additional 'smearing' of toothpaste on the teeth, twice daily. During TP1-TP4, the participants were instructed to brush 3 times per day using 1.5 g of toothpaste without rinsing. Salivary fluoride levels increased with toothpaste fluoride content (p < 0.001), although major interindividual and intraindividual variations were observed. The highest fluoride values appeared in the morning and at night (p < 0.001). Saturation indices for calcium fluoride were affected by the fluoride content in pastes (p < 0.05). Concerning hydroxyapatite and fluorapatite, indices were highest with the MFP toothpaste and extra calcium (NS to p < 0.05). Use of a high-fluoride toothpaste resulted in significantly increased fluoride levels in whole saliva and mineral saturation indices were indeed influenced by choice of toothpaste. © 2015 S. Karger AG, Basel.
    Caries Research 08/2015; 49(5):489-498. DOI:10.1159/000434730 · 2.28 Impact Factor
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    ABSTRACT: Background: Previous studies have suggested that children with oral clefts may have higher caries prevalence in comparison with non-cleft controls but the relative importance of the potential risk factors is not clear. The aim of this study was to compare the caries risk profiles in a group of cleft lip and/or palate (CL(P)) children with non-cleft controls in the same age using a computerized caries risk assessment model. Methods: The study group consisted of 133 children with CL(P) (77 subjects aged 5 years and 56 aged 10 years) and 297 non-cleft controls (133 aged 5 years and 164 aged 10 years). A questionnaire was used to collect data concerning the child's oral hygiene routines, dietary habits and fluoride exposure. Oral hygiene was assessed using Quigley-Hein plaque Index and the caries prevalence and frequency was scored according to the International Caries Detection and Assessment System. Whole saliva samples were analyzed for mutans streptococci, lactobacilli, buffering capacity and secretion rate. The risk factors and risk profiles were compared between the groups with aid of Cariogram and the estimated risk for future caries was categorized as "high" or "low". Results: Children with CL(P) (the entire study group) had significantly higher counts of salivary lactobacilli (p < 0.05) and displayed less good oral hygiene (p < 0.05). More 10-year-old children in the CL(P) group had low secretion rate but this difference was not significant. The average chance to avoid caries ranged from 59 to 67% but there were no significant differences between the groups. The odds of being categorized with high caries risk in the CL(P) group was significantly elevated (OR = 1.89; 95% CI = 1.25-2.86). In both groups, children in the high risk category had a higher caries experience than those with low risk. Conclusion: Children with CL(P) displayed increased odds of being categorized at high caries risk with impaired oral hygiene and elevated salivary lactobacilli counts as most influential factors. The results suggest that a caries risk assessment model should be applied in the routine CL(P) care as a basis for the clinical decision-making and implementation of primary and secondary caries prevention.
    BMC Oral Health 07/2015; 15(1):85. DOI:10.1186/s12903-015-0067-x · 1.13 Impact Factor
  • Svante Twetman · Vineet Dhar ·
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    ABSTRACT: The purpose of this paper was to systematically review the quality of evidence related to self-applied and professionally applied fluorides, antimicrobial agents, fissure sealants, temporary restorations, and restorative care for the prevention and management of early childhood caries (ECC). Relevant papers were selected after an electronic search for literature published in English between 2000 and April 2014. From 877 reports, 33 were included for full review. The quality of evidence was expressed according to the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. There was moderate and limited quality of evidence in support of fluoride toothpaste and fluoride varnish for ECC prevention, while the evidence for fluoride tablets/drops was insufficient. The support for the use of silver diamine fluoride, xylitol, chlorhexidine varnish/gel, povidone iodine, probiotic bacteria, and remineralizing agents (casein phosphopeptide-amorphous calcium phosphate) was insufficient. There was also insufficient quality of evidence for the use of sealants, temporary restorations, and traditional restorative care to reduce incidence of ECC. The results reinforce the need for high quality clinical research and point out the knowledge gaps to be addressed in future studies.
    06/2015; 37(3):246-53.
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    ABSTRACT: The 2014 Early Childhood Caries Conference encompassed evidence-based reviews on the state of the science regarding early childhood carries (ECC) epidemiology, etiology, prevention, and disease management. The purpose of this paper was to discuss the work presented at the conference and identify opportunities in research, policy, and clinical management that may improve early childhood caries outcomes and lower costs of care. While great progress has been made since the 1997 ECC Conference, there remains a paucity of high-quality evidence from randomized controlled trials on what are the most effective means to prevent and manage ECC. Analyses of studies indicate that some approaches, such as chlorhexidine, iodine, and remineralizing agents, have not shown consistent findings in preventing ECC. However, evidence exists to yield recommendations in some areas. There are useful risk assessment indicators to identify preschool children at risk for caries. Fluoridated toothpaste and fluoride varnish currently are the most effective chemotherapeutic strategies to prevent ECC. Motivational interviewing, a form of patient-centered counseling, is effective for motivating oral health behaviors and shows promise for reducing caries. Additionally, evidence is emerging that shows the value of chronic disease management approaches and integrating ECC oral health care within medical care settings. Recommendations for future directions in ECC research and policy were also key outcomes of the conference.
    06/2015; 37(3):294-9.
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    ABSTRACT: To determine the prevalence of dental caries and enamel defects in 5- and 10-year-old Swedish children with cleft lip and/or palate (CL(P)) in comparison to non-cleft controls. The study group consisted of 139 children with CL(P) (80 subjects aged 5 years and 59 aged 10 years) and 313 age-matched non-cleft controls. All children were examined by one of two calibrated examiners. Caries was scored according to the International Caries Detection and Assessment System (ICDAS-II) and enamel defects as presence and frequency of hypoplasia and hypomineralization. The caries prevalence among the 5-year-old CL(P) children and the non-cleft controls was 36% and 18%, respectively (p < 0.05). The CL(P) children had higher caries frequency (initial and cavitated lesions) in the primary dentition than their controls (1.2 vs 0.9; p < 0.05). A significantly higher prevalence of enamel defects was found in CL(P) children of both age groups and anterior permanent teeth were most commonly affected. Preschool children with cleft lip and/or palate seem to have more caries in the primary dentition than age-matched non-cleft controls. Enamel defects were more common in CL(P) children in both age groups.
    Acta odontologica Scandinavica 05/2015; 14. DOI:10.3109/00016357.2015.1044562 · 1.03 Impact Factor
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    ABSTRACT: The aim of this double-blind randomized placebo-controlled trial was to evaluate the effects of probiotic supplements in adjunct to conventional management of peri-implant mucositis. Forty-nine adult patients with peri-implant mucositis were consecutively recruited after informed consent. After initial mechanical debridement and oral hygiene instructions, the patients received a topical oil application (active or placebo) followed by twice-daily intake of lozenges (active or placebo) for 3 months. The active products contained a mix of two strains of Lactobacillus reuteri. Patients were clinically monitored and sampled at baseline and after 1, 2, 4, 12 and 26 weeks. The clinical end-points were pocket-probing depth (PPD), plaque index (PI) and bleeding on probing (BOP). In addition, the subgingival microbiota was processed with checkerboard DNA-DNA hybridization and samples of gingival crevicular fluid (GCF) were analyzed for selected cytokines with the aid of multiplex immunoassays. After 4 and 12 weeks, all clinical parameters were improved in both the test and the placebo group. PPD and BOP were significantly reduced compared with baseline (p < 0.05), but no significant differences were displayed between the groups. The clinical improvements persisted 3 months after the intervention. No major alterations of the subgingival microflora were disclosed and the levels of inflammatory mediators in GCF did not differ between the groups. Mechanical debridement and oral hygiene reinforcement resulted in clinical improvement of peri-implant mucositis and a reduction in cytokine levels. Probiotic supplements did not provide added benefit to placebo.
    Acta odontologica Scandinavica 05/2015; DOI:10.3109/00016357.2015.1040065 · 1.03 Impact Factor
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    ABSTRACT: Bacterial profiles of saliva in subjects with periodontitis and dental caries have been demonstrated to differ from that of oral health. The aim of this comparative analysis of existing data generated by the Human Oral Microbe Identification Microarray (HOMIM) from 293 stimulated saliva samples was to compare bacterial profiles of saliva in subjects with periodontitis and dental caries.
    Journal of Oral Microbiology 04/2015; 7:27429. DOI:10.3402/jom.v7.27429
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    ABSTRACT: Background/objectives: The purpose of the study is to evaluate the effect of daily intake of lozenges containing probiotic bacteria on white spot lesion (WSL) formation as well as on salivary lactobacilli (LB) and mutans streptococci (MS) counts, in patients undergoing orthodontic treatment with fixed appliances. Materials/methods: A randomized double-blind placebo-controlled study design with two parallel arms was employed. Patients (n = 85, mean age 15.9 years) with maxillary braces on at least eight anterior teeth and a remaining treatment period of 7-24 months were finally enrolled and randomly allocated to a test or placebo group. Subjects in the test group were instructed to take one probiotic lozenge containing two strains of Lactobacillus reuteri once daily. An identical lozenge without active bacteria was used in the placebo group. Dental plaque, WSL, and salivary MS and LB levels were recorded at baseline and immediately after debonding. Results: The groups were balanced at baseline. The mean duration of the intervention was 17 months and the total dropout rate was 10 per cent. There were no differences in the incidence of WSL between the groups at debonding. The patients had generally a neglected oral hygiene, both at baseline and at the follow-up. The levels of salivary LB were significantly reduced in both groups (P < 0.05) at the time of debonding compared with baseline, while no alterations of the MS counts were unveiled. Limitations: WSL were scored from photos that may not fully mirror the clinical situation. Chair-side tests estimate the counts of selected bacteria in saliva and do not reflect the entire microbiota. The invention was implemented approximately 6 months after the onset of the fixed appliances and some lesions may have been present at bonding. Conclusions/clinical implications: Daily intake of probiotic lozenges did not seem to affect the development of WSL during orthodontic treatment with fixed appliances.
    The European Journal of Orthodontics 04/2015; DOI:10.1093/ejo/cjv015 · 1.48 Impact Factor
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    Per Rabe · Svante Twetman · Bertil Kinnby · Gunnel Svensäter · Julia R Davies ·
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    ABSTRACT: Objective: To develop a model in which to investigate the architecture of plaque biofilms formed on enamel surfaces in vivo and to compare the effects of anti-microbial agents of relevance for caries on biofilm vitality. Materials and Methodology : Enamel discs mounted on healing abutments in the pre-molar region were worn by three subjects for 7 days. Control discs were removed before subjects rinsed with 0.1% chlorhexidine digluconate (CHX) or 0.2% sodium fluoride (NaF) for 1 minute. Biofilms were stained with Baclight Live/Dead and z-stacks of images created using confocal scanning laser micoscopy. The levels of vital and dead/damaged bacteria in the biofilms, assessed as the proportion of green and red pixels respectively, were analysed using ImageTrak(®) software. Results : The subjects showed individual differences in biofilm architecture. The thickness of the biofilms varied from 28-96µm although cell density was always the greatest in the middle layers. In control biofilms, the overall levels of vitality were high (71-98%) especially in the area closest to the enamel interface. Rinsing with either CHX or NaF caused a similar reduction in overall vitality. CHX exerted an effect throughout the biofilm, particularly on the surface of cell clusters whereas NaF caused cell damage/death mainly in the middle to lower biofilm layers. Conclusion : We describe a model that allows the formation of mature, undisturbed oral biofilms on human enamel surfaces in vivo and show that CHX and NaF have a similar effect on overall vitality but differ in their sites of action.
    The Open Dentistry Journal 03/2015; 9(1):106-11. DOI:10.2174/1874210601509010106
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    ABSTRACT: To identify, appraise and summarize existing knowledge and knowledge gaps in practice-relevant questions in pediatric dentistry. A systematic mapping of systematic reviews was undertaken for domains considered important in daily clinical practice. The literature search covered questions in the following domains: behavior management problems/dental anxiety; caries risk assessment and caries detection including radiographic technologies; prevention and non-operative treatment of caries in primary and young permanent teeth; operative treatment of caries in primary and young permanent teeth; prevention and treatment of periodontal disease; management of tooth developmental and mineralization disturbances; prevention and treatment of oral conditions in children with chronic diseases/developmental disturbances/obesity; diagnosis, prevention and treatment of dental erosion and tooth wear; treatment of traumatic injuries in primary and young permanent teeth and cost-effectiveness of these interventions. Abstracts and full text reviews were assessed independently by two reviewers and any differences were solved by consensus. AMSTAR was used to assess the risk of bias of each included systematic review. Reviews judged as having a low or moderate risk of bias were used to formulate existing knowledge and knowledge gaps. Out of 81 systematic reviews meeting the inclusion criteria, 38 were judged to have a low or moderate risk of bias. Half of them concerned caries prevention. The quality of evidence was high for a caries-preventive effect of daily use of fluoride toothpaste and moderate for fissure sealing with resin-based materials. For the rest the quality of evidence for the effects of interventions was low or very low. There is an urgent need for primary clinical research of good quality in most clinically-relevant domains in pediatric dentistry.
    PLoS ONE 02/2015; 10(2):e0117537. DOI:10.1371/journal.pone.0117537 · 3.23 Impact Factor
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    Gunnel Hänsel Petersson · Svante Twetman ·
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    ABSTRACT: To validate baseline caries risk classifications according to the Cariogram model with the actual caries development over a 3-year period in a group of young adults living in Sweden. The study group consisted of 1,295 19-year-old patients that completed a comprehensive clinical baseline examination, including radiographs and salivary tests. An individual caries risk profile was computed and the patient was placed in one of five risk categories. After 3 years, 982 patients (75.8%) were re-examined and caries increment for each patient was calculated. The outcome was expressed as sensitivity, specificity and predictive values and compared with a risk assessment scheme used in Public Dental Service. The drop-outs displayed more risk factors and a significantly higher caries burden at baseline compared with those that remained in the project (p < 0.05). There was a strong association between the Cariogram risk categories and the 3-year caries increment on cavity level but the predictive values were modest. The high or very high caries risk categories yielded high specificities (>90%) but poor sensitivities. The low risk groups displayed higher sensitivities on expense of impaired specificities. No combinations proved clinically useful values according to Yuoden's index. Within the limitations of the present study, the computer-based Cariogram did not perform better than a caries risk assessment scheme based on past caries experience and caries progression, over a 3-year period in young adults.
    BMC Oral Health 01/2015; 15(1):17. DOI:10.1186/1472-6831-15-17 · 1.13 Impact Factor
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    ABSTRACT: Aim: To investigate selected lifestyle factors in relation to active caries and restored root surface lesions in adults. Materials and methods: Based on clinical examinations and questionnaires, data on root caries, socioeconomic status, body mass index, dietary habits, alcohol consumption, tobacco use and oral hygiene routines were collected from 4369 adults aged 21-89 who took part in a survey covering 13 municipalities across Denmark. Uni- and multivariate logistic regression analyses were applied to analyse the relationship between the independent lifestyle variables and active caries and restored root surface lesions, respectively. Results: The prevalence of active root caries was 4%, while 26% displayed restored root surfaces. The sugar intake was not related to root caries. A multivariate logistic regression analysis revealed that, in subjects aged 45 or over, smoking and wearing dentures were significantly associated with presence of active root caries (p<0.01). The intake of 15 drinks or more per week was associated with higher odds of root surface restorations compared with no alcohol intake (OR=1.7; p<0.001). Conclusions: Lifestyle factors such as tobacco use and alcohol consumption, as well as wearing dentures, were significantly associated with the occurrence of untreated caries and restored root surface lesions, especially in persons over 45. Thus, such lifestyle factors should be taken into consideration, identifying persons with a need of preventive dental services. In addition, oral health education should focus on the possible risks of smoking and a high alcohol intake.
    Acta Odontologica Scandinavica 12/2014; 73(6):1-7. DOI:10.3109/00016357.2014.986753 · 1.03 Impact Factor
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    ABSTRACT: Objective The aim of the present study was to investigate the reproducibility of bacterial enumeration from subsequent subgingival samples collected from patients with peri-implant mucositis. Material and methods Duplicate microbial samples from 222 unique implant sites in 45 adult subjects were collected with paper points and analyzed using the checkerboard DNA-DNA hybridization technique. Whole genomic probes of 74 preselected bacterial species were used. Based on the bacterial scores, Cohen’s kappa coefficient was used to calculate the inter-annotator agreement for categorical data. The percentage agreement was considered as “good” when the two samples showed the same score or differed by 1 to the power of 10. Results Moderate to fair kappa values were displayed for all bacterial species in the test panel (range 0.21-0.58). There were no significant differences between Gram-positive and Gram-negative species. The percentage of good agreement between the first and second samples averaged 74.7 % (n = 74; range 56-83 %), while the proportion of poor agreement ranged from 1 to 19 % for the various strains. Conclusion While an acceptable clinical agreement was obtained in most cases, diverging bacterial scores may appear in subgingival samples collected at the same time point from patients with peri-implant mucositis. Clinical relevance The broad bulky base of implant crowns may present an obstacle for the collection of reproducible subgingival samples with paper points.
    Clinical Oral Investigations 09/2014; 19(5). DOI:10.1007/s00784-014-1324-0 · 2.35 Impact Factor
  • Lisa Twetman · Svante Twetman ·
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    ABSTRACT: Aim: To compare the prevalence and levels of salivary Mutans Streptococci (MS) assessed with two commercial chair-side methods based on culture growth or monoclonal antibodies, respectively. Material and methods: The study group consisted of a convenience sample of 89 adults, 23-72 years of age, referred to a maxillofacial hospital clinic with a caries history. Stimulated whole saliva samples were collected and the number of MS was assessed with the Dentocult-SM Strip Mutans (DSM) and the Saliva-Check Mutans (SCM). The outcome was compared with conventional anaerobic laboratory cultivation on selective MSB agar. Results: The prevalence of ≥ 5 × 10(5) CFU was 21%, 62%, and 73% with the SCM, DSM and MSB-cultivation, respectively. The correlation between DSM and SCM tests was r = 0.49 (p < 0.05) but the agreement on the high levels was fair. In comparison with the MSB agar, DSM provided acceptable levels of sensitivity and specificity while the SCM displayed a poor sensitivity but a perfect specificity. Both chair-side methods were significantly related to the prevalence of active root caries lesions (p < 0.05). Conclusions: The two chair-side salivary tests were significantly correlated and due their high specificity, they may be sensitive enough for screening purposes and for patient-centered promotion of oral health.
    Oral health and dental management 09/2014; 13(3):580-3.
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    ABSTRACT: This article describes the construction and characterization of a mariner-based transposon vector designed for use in oral streptococci, but with a potential use in other Gram-positive bacteria. The new transposon vector, termed pMN100, contains the temperature-sensitive origin of replication repATs-pWV01, a selectable kanamycin resistance gene, a Himar1 transposase gene regulated by a xylose-inducible promoter, and an erythromycin resistance gene flanked by himar inverted repeats. The pMN100 plasmid was transformed into Streptococcus mutans UA159 and transposon mutagenesis was performed via a protocol established to perform high numbers of separate transpositions despite a low frequency of transposition. The distribution of transposon inserts in 30 randomly picked mutants suggested that mariner transposon mutagenesis is unbiased in S. mutans. A generated transposon mutant library containing 5000 mutants was used in a screen to identify genes involved in the production of sucrose-dependent extracellular matrix components. Mutants with transposon inserts in genes encoding glycosyltransferases and the competence-related secretory locus were predominantly found in this screen.
    MicrobiologyOpen 06/2014; 3(3). DOI:10.1002/mbo3.171 · 2.21 Impact Factor
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    ABSTRACT: To evaluate the performance of an impedance spectroscopy technology for detecting non-cavitated occlusal caries lesions in permanent teeth in vitro. The method was compared with a commonly used laser fluorescence device and validated against histology. A non-cavitated sample of 100 extracted posterior teeth was randomly selected and assessed for caries on enamel and dentin level with aid of CarioScan PRO (ACIS) and DIAGNOdent pen (LF pen) by three examiners. After the measurements, the extension of the lesion was histologically determined as gold standard. Sensitivity, specificity, accuracy and receiver-operating curves were calculated. Intra- and inter-examiner reproducibility was expressed by intra class correlation coefficients. The histological caries prevalence was 99% and 41% exhibited dentin caries. The ACIS technique displayed high specificities but almost negligible sensitivities at readings >50. A similar pattern was noted for the LF pen at readings >30. The intra- and inter-examiner reproducibility varied between 0.47 and 0.98 and the values were generally lower for the ACIS technique than for the LF pen. The inter-examiner agreement reached excellent levels with both methods. In vitro,the ACIS technique showed a low ability to disclose occlusal caries lesions in the enamel and/or dentin of non-cavitated permanent molars. However, further in vivo studies of permanent occlusal surfaces are needed to mirror the clinical situation.
    The Open Dentistry Journal 04/2014; 8(1):28-32. DOI:10.2174/1874210601408010028
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    ABSTRACT: The bacterial profile of saliva is composed of bacteria from different oral surfaces. The objective of this study was to determine whether different diet intake, lifestyle, or socioeconomic status is associated with characteristic bacterial saliva profiles. Stimulated saliva samples from 292 participants with low levels of dental caries and periodontitis, enrolled in the Danish Health Examination Survey (DANHES), were analyzed for the presence of approximately 300 bacterial species by means of the Human Oral Microbe Identification Microarray (HOMIM). Using presence and levels (mean HOMIM-value) of bacterial probes as endpoints, the influence of diet intake, lifestyle, and socioeconomic status on the bacterial saliva profile was analyzed by Mann-Whitney tests with Benjamini-Hochberg's correction for multiple comparisons and principal component analysis. Targets for 131 different probes were identified in 292 samples, with Streptococcus and Veillonella being the most predominant genera identified. Two bacterial taxa (Streptococcus sobrinus and Eubacterium [11][G-3] brachy) were more associated with smokers than non-smokers (adjusted p-value<0.01). Stratification of the group based on extreme ends of the parameters age, gender, alcohol consumption, body mass index (BMI), and diet intake had no statistical influence on the composition of the bacterial profile of saliva. Conversely, differences in socioeconomic status were reflected by the bacterial profiles of saliva. The bacterial profile of saliva seems independent of diet intake, but influenced by smoking and maybe socioeconomic status.
    Journal of Oral Microbiology 04/2014; 6(1). DOI:10.3402/jom.v6.23609

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  • 2008-2015
    • IT University of Copenhagen
      København, Capital Region, Denmark
  • 2001-2013
    • Umeå University
      • • Faculty of Medicine
      • • Department of Odontology
      Umeå, Västerbotten, Sweden
  • 2000-2013
    • Malmö University
      • • Department of Orthodontics
      • • Faculty of Odontology (OD)
      Malmö, Skåne, Sweden
  • 1989-2010
    • Länssjukhuset Ryhov
      Jönköping, Jönköping, Sweden
  • 1982-2006
    • Karolinska Institutet
      • Department of Dental Medicine
      Solna, Stockholm, Sweden
  • 2003
    • University of Southern California
      Los Angeles, California, United States
  • 1998-1999
    • Lund University
      Lund, Skåne, Sweden
  • 1996
    • King Faisal Specialist Hospital and Research Centre
      • Department of Dentistry
      Ar Riyāḑ, Ar Riyāḑ, Saudi Arabia
    • Karlstad Central Hospital
      Karlstad, Värmland, Sweden