Search

Objective. This study assesses the prevalence of caries and some background factors in 4-year-old children in the city of Umeå, northern Sweden, and compares this with data from earlier studies to reveal changes over time. Materials and methods. Children from the catchment areas of three Public Dental Health Service clinics in Umeå ( n = 224) born during the third quarter of 2008 were invited to undergo a clinical dental examination. Decayed surfaces (including both dentine and enamel, except for enamel lesions on buccal and lingual surfaces), missing and filled surfaces (dmfs) were recorded using the same methods and criteria as in a series of earlier studies performed between 1980-2007. Background data were collected in a case-history and a questionnaire. Results. The proportion of children with caries significantly decreased from 2007 (38%) to 2012 (22%) ( p < 0.05). In addition, the distribution of dmfs differed significantly between these years ( p < 0.05). More immigrant children had caries (42%) than non-immigrant children (15%) ( p < 0.05). For children with caries, there were no significant changes in the distribution of dmfs between 1980-2012 ( p > 0.05). An immigrant background was associated with a lower frequency of tooth brushing and a higher intake of ice cream, sweets and chocolate drinks ( p < 0.05). Conclusion. Although the proportion of children with caries declined between 2007-2012, this decline was limited to non-immigrant children. Since 1980 the distribution of dmfs remained unchanged among children with caries. More research on interventions for changing oral health behaviours is needed, specifically for immigrant children. [ABSTRACT FROM AUTHOR]

Objective. Co-aggregation and growth inhibition abilities of probiotic bacteria may play a key role in their interference with the oral biofilm. The aim was to investigate the in vitro ability of selected commercial probiotic lactobacilli to co-aggregate and inhibit growth of oral mutans steptococci isolated from adults with contrasting levels of caries. Materials and methods. Mutans streptococci (MS) strains were isolated from caries-free ( n == 3) and caries-susceptible ( n == 5) young adults and processed with eight commercial probiotic lactobacilli strains. One laboratory reference strain ( S. mutans Ingbritt) was selected as control. Co-aggregation was determined spectrophotometrically and growth inhibition was assessed with the agar overlay technique. Results. All probiotic lactobacilli showed an ability to co-aggregate with the isolated MS strains. Statistically significant differences ( p < 0.05) were found between strains from different individuals when compared with the reference strain. The selected lactobacilli inhibited MS growth, but the ability varied between the strains and was clearly related to pH. No differences were observed between the different MS strains from caries-free and caries-susceptible individuals. Conclusions. The selected lactobacilli displayed co-aggregation activity and inhibited growth of clinical mutans streptococci. The growth inhibition was strain-specific and dependent on pH and cell concentration. The findings indicate that the outcome of lactobacilli-derived probiotic therapy might vary between individuals and depend on the specific strain used. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the in vitro abilities of probiotic bacteria derived from consumer products to coaggregate with caries-associated mutans streptococci. Material and Methods. Six lactobacillus strains (L. acidophilus (CCUG 5917), L. plantarum 299v, L. rhamnosus GG and LB21, L. paracasei F19, L. reuteri PTA5289) were cultivated under anaerobic conditions at 37°C in Man Rogosa Sharpe (MSB) broth for 24 h. Four strains of human streptococci (S. mutans Ingbritt, S. mutans (ATCC 25175), S. mutans GS-5, S. sobrinus (ATCC 33478) were similarly grown in Brain Heart Infusion (BHI) broth. A gastrointestinal pathogen (Escherichia coli) was aerobically cultivated on BHI broth as a positive control. After incubation, the bacteria were aerobically harvested, washed, and suspended in 10 mmol/l phosphate-buffered saline (pH 7.2). The probiotic strains were characterized with the API 50 CH system to confirm their identity. Coaggregation was determined by spectrophotometry in mixtures and bacterial suspensions alone after 1, 2, 4, and 24 h and expressed as the aggregation ratio (%). Results. All probiotic strains showed coaggregation abilities with the oral pathogens and the results were strain specific and dependent on time. S. mutans GS-5 exhibited a significantly higher ability to coaggregate with all the probiotic strains than the other mutans streptococci and E. coli. The differences among the probiotic strains were modest with L. acidophilus being the most prone and L. rhamnosus LB21 the least prone to coaggregate with the oral streptococci. Conclusions. The results demonstrated different abilities of lactobacilli-derived probiotic bacteria to coaggregate with selected oral streptococci. Aggregation assays may be a useful complement for screening of probiotic candidates with possible anti-caries properties. [ABSTRACT FROM AUTHOR]

Objective. To investigate the effect of a chewing gum containing probiotic bacteria on gingival inflammation and the levels of selected inflammatory mediators in gingival crevicular fluid (GCF). Material and Methods. Forty-two healthy adults with moderate levels of gingival inflammation entered a double-blind placebo-controlled study design. The subjects were randomly assigned to one of three parallel arms: Group A/P was given one active and one placebo gum daily, Group A/A received two active chewing gums, and Group P/P two placebo gums. The chewing gums contained two strains of Lactobacillus reuteri: ATCC 55730 and ATCC PTA 5289 (1×108 CFU/gum, respectively). The subjects were instructed to chew the gums for 10 min over the course of 2 weeks. Bleeding on probing (BOP) and GCF sampling were conducted at baseline and after 1, 2 and 4 weeks. The levels of IL-1β, TNF-α, IL-6, IL-8 and IL-10 were determined using luminex technology and multiplex immunoassay kits. Results. BOP improved and GCF volume decreased in all groups during the chewing period, but the results were statistically significant (p<0.05) only in Groups A/P and A/A. The levels of TNF-α and IL-8 decreased significantly (p<0.05) in Group A/A compared with baseline after 1 and 2 weeks, respectively. A non-significant decreasing tendency was also observed concerning IL-1β during the chewing period. The levels of IL-6 and IL-10 were unaffected in all groups after 1 and 2 weeks. Conclusions. The reduction of pro-inflammatory cytokines in GCF may be proof of principle for the probiotic approach combating inflammation in the oral cavity. [ABSTRACT FROM AUTHOR]

Objective. The aim was to investigate the effect of high and low amounts of xylitol on the interdental plaque-pH, directly and after sucrose challenge, in schoolchildren with habitual consumption. Material and methods. The study group consisted of 11 healthy children (10–15 years) with low caries risk and the experiment had a single-blind crossover (Latin square) design. After a 2-week run-in period with a daily 4.0&ThickSpace;g xylitol intake, the children were subjected to single-dose exposures of chewing gums with (i) paraffin (CTR; no xylitol), (ii) low-dose xylitol (LX; 2.0&ThickSpace;g xylitol), and (iii) high-dose xylitol (HX; 6.0&ThickSpace;g xylitol) in a randomized order separated by a washout period of 1 week. Samples of chewing-stimulated whole saliva were collected prior to and after the experimental period for determination of bacterial counts. The outcome measures were in situ plaque-pH (micro-touch method) and area under the pH curve (AUC). Results. The AUC was significantly greater ( p [ABSTRACT FROM AUTHOR]