L. Papagiannoulis

The microbiota on different oral surfaces in healthy children

INTRODUCTION Knowledge of the early oral colonization patterns could provide a better understanding of oral biofilm development and disease initiation that in turn could be the basis for early preventive programmes. METHODS Microbial samples were collected from five different oral habitats from a total of 93 children (age 3-12 years), attending the Dental School of the University of Athens, who were split into three age groups. A total of 38 microbial species were sought out by the checkerboard DNA-DNA hybridization technique. RESULTS All of the test species, except Parvimonas micra and Porphyromonas gingivalis, differed significantly among sample locations providing quite distinct microbial profiles for the different oral surfaces. Supragingival and subgingival plaque had similar profiles and exhibited higher proportions of Actinomyces species and Green complex while soft tissue samples were dominated by streptococci of the Yellow complex. The profiles of the tongue dorsum and saliva were also similar. Many of the species were in similar proportions in all three age groups for a given location. Periodontal pathogens showed increases in proportions with increasing age. Specifically, the Red complex species (Tannerella forsythia, P. gingivalis, Treponema denticola) showed a significant increase in proportion with age (P < 0.05) in all sample locations. CONCLUSIONS The results showed a pattern of colonization in children similar to that previously found in adults. Differences in the profile between age groups suggest a gradual maturation of the oral microbiota, with it being made up of an increasing number of Orange and Red complex species.

Effect of topical fluoride agents on the morphologic characteristics and composition of resin composite restorative materials

STATEMENT OF PROBLEM The high reactivity of fluoride agents used in topical fluoride treatments have raised important questions on their potential adverse effects on restorative materials. PURPOSE The purpose of this study was to evaluate the effect of topical fluoride agents used for office or home treatments on the surface morphologic characteristics and composition of composite restoratives. MATERIAL AND METHODS The fluorides used were Act, Phosflur, Gel II, Prevident, Stop, Butler APE, Nupro, and Omni Gel & Rinse. The composites tested were Brilliant DI, Heliomolar Ro, Herculite XRV, and P-50. The pH of the fluorides was measured as received and after dilution with water at a 1:3 volume ratio. The composites were subjected to the fluoride treatments until the total number of applications simulated the equivalent of 4 years under treatment. The changes induced on the surface morphologic features and composition of the restoratives were assessed by multiple internal reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, and x-ray microanalysis. RESULTS All fluorides showed an acidic pH that was not significantly changed after dilution, except Stop, which exhibited a significant pH reduction. All fluorides increased the amount of loosely bound water in the composite matrix. Butler APF gel was the most aggressive for Brilliant DI and Herculite XRV, leading to excessive surface degradation, porosity, destruction of the filler-matrix interface, filler dissolution, and debonding. A reduction in the extent of remaining C = C bonds was observed in Herculite XRV after Butler APF treatment; Phosflur, Gel II, and Prevident had a milder effect. Treatment of Brilliant Dl and Herculite XRV with Omni Gel & Rinse resulted in the formation of a stable precipitation layer rich in barium, phosphorus, tin, oxygen, and fluoride. P-50 was severely affected at the resin-matrix interface after Stop treatment, whereas Omni Gel & Rinse induced fewer surface changes. Heliomolar Ro was the least affected restorative regardless of the type of fluoride used.

Distribution of selected cariogenic bacteria in five different intra-oral habitats in young children.

BACKGROUND Knowledge of the colonization patterns and composition of the oral microbiota can lead to a better understanding of disease initiation. AIM The aim of this study was to examine the distribution of selected cariogenic bacteria in samples from five different oral habitats in young Greek children. DESIGN Ninety-three children 3-12 years old (mean + SD 7.9 +/- 2.5) (60.2% male, 39.8% female) participated and split into three different age groups: primary (3-6 years), early mixed (6-9 years), and mixed dentition (9-12 years). Samples for bacterial enumeration were taken from saliva, supragingival and subgingival plaque, tongue dorsum, and soft tissues from each child, and were further analysed using checkerboard DNA-DNA hybridization. RESULTS Mean counts and proportions of all the test bacteria differed significantly among sample locations. Cariogenic bacteria were present in almost all healthy children. Mean proportions of Streptococcus mutans isolated from soft tissue and Streptococcus sanguinis from soft tissue, subgingival and saliva samples increased significantly with age, whereas the opposite was seen for Lactobacillus acidophilus. CONCLUSIONS Cariogenic bacteria were present in almost all young children. Soft tissues, saliva, and tongue were more often colonized by cariogenic streptococcal species than teeth. These surfaces may serve as reservoirs for oral pathogens, requiring attention during preventive interventions.

Caries-preventive effectiveness of fluoride varnish as adjunct to oral health promotion and supervised tooth brushing in preschool children: a double-blind randomized controlled trial.

OBJECTIVES To evaluate the effect of biannual fluoride varnish applications in preschool children as an adjunct to school-based oral health promotion and supervised tooth brushing with 1000ppm fluoride toothpaste. METHODS 424 preschool children, 2-5 year of age, from 10 different pre schools in Athens were invited to this double-blind randomized controlled trial and 328 children completed the 2-year programme. All children received oral health education with hygiene instructions twice yearly and attended supervised tooth brushing once daily. The test group was treated with fluoride varnish (0.9% diflurosilane) biannually while the control group had placebo applications. The primary endpoints were caries prevalence and increment; secondary outcomes were gingival health, mutans streptococci growth and salivary buffer capacity. RESULTS The groups were balanced at baseline and no significant differences in caries prevalence or increment were displayed between the groups after 1 and 2 years, respectively. There was a reduced number of new pre-cavitated enamel lesions during the second year of the study (p=0.05) but the decrease was not statistically significant. The secondary endpoints were unaffected by the varnish treatments. CONCLUSIONS Under the present conditions, biannual fluoride varnish applications in preschool children did not show significant caries-preventive benefits when provided as an adjunct to school-based supervised tooth brushing with 1000ppm fluoride toothpaste. CLINICAL SIGNIFICANCE In community based, caries prevention programmes, for high caries risk preschool children, a fluoride varnish may add little to caries prevention, when 1000ppm fluoride toothpaste is used daily.

Progression of proximal caries in children with different caries indices: A 4-year radiographic study

Aim: This was to investigate survival rate, median survival time and differences in the progression of different stages of proximal caries in 196 children, aged 6 to 8 years old, with different caries index at baseline examination. Methods: Based on DMFS/dmfs values, children were categorized as low, moderate and high caries index groups. Subjects with DMFS/dmfs smaller or equal to half of a child’s age were classified as low caries index group; children with DMFS/dmfs greater than half and smaller than, or equal to, the child’s age as moderate; those with DMFS/dmfs greater than the child’s age as high. Proximal caries and its progression were diagnosed from bitewing radiographs taken at 1 — year intervals over a period of 4 years. The mesial surface of the first permanent molars, mesial and distal surfaces of the first and second primary molars and distal surfaces of the primary canines were examined. Sound surfaces, caries lesions in the external and internal half of the enamel and external, middle, internal third of the dentine as well as filled, extracted and exfoliated teeth were recorded. Statistics: A life table analysis was performed to estimate survival rate and median survival time of each state of proximal caries and differences between the groups in the progression of the proximal lesions were tested with the Wilcoxon pairwise comparison statistic. Results: There were statistically significant differences in the caries rate of the sound proximal surfaces of the primary teeth between the low and high caries index groups. Also, statistically significant differences between these two groups were found in the progression of the external half of the enamel caries in the first permanent molars and in the primary teeth. Conclusions: A high caries index increases the risk of developing caries in the sound proximal surfaces of posterior primary teeth and causes faster progression of the external half of the enamel lesions in the first permanent molars and posterior primary teeth.

Periodontal and microbiological parameters in children and adolescents with cleft lip and /or palate

Objective. To evaluate the oral hygiene and the periodontal condition of children and adolescents with cleft lip and/or palate (CLP). Methods. Forty-one children and adolescents, 4-18 years, with CLP and 41 normal controls participated. Clinical parameters examined were the plaque and gingival index and Community Periodontal Index of Treatment Needs. For teeth in the cleft area, probing pocket depth, bleeding on probing, and tooth mobility were also evaluated. Samples of subgingival plaque were collected from 21 randomly selected patients of each group. Results. The CLP group had generally poorer oral hygiene (plaque index significantly higher) compared with the control. Children in both groups presented mild degree of gingivitis. Teeth in the cleft area had significantly higher pocket probing depth and tooth mobility, compared with corresponding teeth in the control group. The microbial analysis did not reveal significant differences in the composition of the subgingival microbiota between groups. Teeth in the cleft presented higher isolation frequencies and mean percentages of periodontopathic bacteria. Conclusion. Youngsters with CLP showed poor oral hygiene and worse periodontal condition, compared with controls. The above results advocate their participation in an intensive preventive dental programme that should start at an early age, possibly decreasing the risk of future periodontal disease.

Emotional stress and craniomandibular dysfunction in children.

ABSTRACT This study investigated the relationship between craniomandibular dysfunction (CMD) and emotionally stressful states measured by the urinary catecholamines in 314 children aged six to eight years. The children were examined clinically and interviewed by the same investigator. During the clinical examination the following variables were recorded: maximal mouth opening with and without pain, deviation of the mandible in opening wide, muscle and temporomandibular joint (TMJ) tenderness or pain and sounds from the TMJ. The variables recorded during the interview were headaches, difficulties in opening wide, pain upon opening wide, and clicking. A questionnaire was distributed to the parents to collect information regarding socioeconomic factors. A 24-hour urine sample was collected for each subject and analyzed by the high performance liquid chromatography (HPLC) technique to assay the catecholamine content. The logistic multiple regression analysis was carried out to test whether craniomandibular dysfunction was affected by the studied variables. A 95% probability level was used. The results showed that epinephrine had a significant effect on TMJ tenderness, while norepinephrine and dopamine did not have a significant association with any of the signs and symptoms of CMD. The data suggest that emotionally stressful states increase the probability of developing TMJ tenderness in children of this age.

Histological validation of a laser fluorescence device for occlusal caries detection in primary molars

AIM: This was to validate in vitro a laser fluorescence device, DIAGNOdent™ 2095-DD, on the detection of occlusal caries in primary molars using the histological examination as the gold standard and to compare the laser fluorescence findings to the results of the conventionally used diagnostic methods. STUDY DESIGN AND METHODS: 111 occlusal pits in 24 extracted primary molars were examined for caries by one trained operator (Intra-examiner Reliability K>0.83), using direct visual (DV), indirect visual (IDV), radiographic (XR) and fluorescence (DD) examinations and then the extent of caries was determined histologically. Sensitivity, specificity, accuracy and the area under the ROC curve — AUC were calculated for all methods, using the histological evaluation as the gold standard. STATISTICS: Differences between examination methods were estimated by pair-wise comparison of their respective AUC. RESULTS: DD’s sensitivity for enamel and for dentine lesions respectively was 0.90 and 0.36, its specificity 0.36 and 0.91 and its accuracy 0.61 and 0.65. The DD device exhibited better sensitivity than specificity for enamel lesions and better specificity than sensitivity for lesions into dentine. The DD device was found to have the highest sensitivity for lesions into enamel, specificity and accuracy and as well as the largest AUC compared with all other methods. For lesions into dentine however, according to AUC values the DD was not statistically significant different from the other methods. CONCLUSION: Compared with the other methods, the DD had the highest validity for enamel caries while its validity for caries into dentine was not statistical different from the other methods.