Salivary microbiota and caries occurrence in Mutans Streptococci-positive school children.

AIM: To compare the composition of the salivary microbiota in caries-affected vs. caries-free mutans streptococci (MS)- positive children with mixed dentition. MATERIALS AND METHODS: Twenty eight healthy, 11-12-year-old schoolchildren with high MS counts (>10⊃5 CFU/mL) were included in this study. The children were screened with the Dentocult SM Strip Mutans test (Orion Diagnostica, Espoo, Finland) and examined using the International Caries Detection and Assessment System (ICDAS). The microbial composition of the saliva was assessed using the Human Oral Microbe Identification Microarray (HOMIM). Microbial differences between caries-affected (n=18) and caries-free children (n=10) were compared by Mann-Whitney analysis. RESULTS: The microbiota of the caries-affected vs. caries-free children was rather similar. Abiotrophia defectiva and Actinomyces meyeri/A. odontolyticus were significantly higher in caries-affected than in caries-free children (p=0.006, 0.046, respectively). Shuttleworthia satelles was significantly higher in caries-free compared to caries-affected children (p=0.031). A. defectiva and A. meyeri/A. odontolyticus correlated positively with caries severity measured by ICDAS Caries Index (p = 0.494, 0.454, 0.400 respectively) while S. satelles was negatively correlated with caries severity (p= -0.489). CONCLUSIONS: Salivary A. defectiva and A. meyeri/A. odontolyticus and are associated with caries occurrence in MS-positive children with mixed dentition.

Cytokines as diagnostic markers of pulpal inflammation.

AIM: To measure and compare the levels of the cytokines IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ in pulpal blood from irreversible pulpitis, asymptomatic caries exposure and normal pulps. METHODOLOGY: Blood was obtained from pulp exposure sites using cotton pellets. Twenty-five samples were obtained from normal teeth, 40 from asymptomatic caries-exposed pulps and 43 from irreversible pulpitis teeth. Cytokine levels were determined by high-sensitivity ELISA. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U-tests. RESULTS: Significantly higher levels (P < 0.05) of IL-6, IL-8, IL-10, TNF-α and IFN-γ were detected in caries-exposed pulps and irreversible pulpitis as compared to normal teeth. IL-2 and IL-10 levels were significantly higher (P < 0.05) in caries-exposed pulps as compared to irreversible pulpitis, whilst IL-8 was significantly higher (P < 0.001) in irreversible pulpitis as compared to caries-exposed teeth. Most interestingly, IL-6/IL-10 and IL-8/IL-10 ratios were significantly higher (P < 0.001) in irreversible pulpitis compared with both caries-exposed and normal teeth. CONCLUSION: Levels of IL-8 and the ratios of IL-6/IL-10 and IL-8/IL-10 have the potential to be indicators of pulpal inflammation in caries exposure cases. Cytokine estimation in pulpal blood may help in the diagnosis of pulpal inflammation.

Caries recurrence after treatment under general anaesthesia for early childhood caries: a retrospective cohort study.

AIM: To evaluate rates of caries relapse and explore factors affecting relapse rates after comprehensive dental treatment under general anaesthesia (GA). METHODS: A retrospective cohort study of children ≤6 years of age at the time of reference GA (RGA) who were in an anaesthetic low risk category [American Society of Anesthesiologists (ASA) classification 1 or 2], and had completed 36 months follow-up period was conducted. Patients' demographics and dental records were collected. Associations between relapse rate and different factors affecting relapse rates were evaluated. RESULTS: A total of 278 children with mean age of 47 ± 14 months were included. Over 8 % of children had more than one GA, 88 % attended their post-operative follow-up appointment and 45 % returned for all recall appointments over 3 years. During the 3-year follow-up, the relapse rate was 22 %. ASA-2 children and those with less than full primary dentition present at the RGA were more than twice as likely to experience caries relapse as compared to ASA-1 children (OR = 2.46, 95 % CI 1.33-4.56) and those with mixed dentition present at the RGA (OR = 2.74, 95 % CI 1.27-5.91). CONCLUSION: ASA-2 health status and having less than a full primary dentition were major predictors of caries relapse after dental treatment under GA.

Effects of xylitol mouthrinse on Streptococcus mutans.

OBJECTIVES: This study aimed to measure the effect of xylitol mouthrinse on salivary Streptococcus mutans counts. METHODS: Subjects in the study group (n = 25) used xylitol mouthrinse for 4 weeks, while another group (n = 25) used saccharine mouthrinse. S. mutans were measured before and after intervention. RESULTS: At the baseline the mean S. mutans scores were 3.9 (SE = 0.03) and 3.9 (0.04) for the xylitol group and control group respectively, while the scores were 2.8 (0.13) and 3.9 (0.07) after the intervention. Significant reductions (p < 0.01) in the scores of S. mutans were found after the four week use of xylitol mouthrinse. CONCLUSIONS: Significant reductions in the scores of S. mutans were found after the four week use of 20% xylitol mouthrinse. The bacteriostatic effect of xylitol mouthrinse on S. mutans may be comparable to other xylitol products. Further studies are needed to confirm both the short and long term effects of xylitol mouthrinse.