"Borderline" fluorotic region in Serbia: correlations among fluoride in drinking water, biomarkers of exposure and dental fluorosis in schoolchildren.

This study explores relation between dental fluorosis occurrence in schoolchildren, residents of Ritopek, a small local community near Belgrade, and fluoride exposure via drinking water. Additionally, fluoride levels were determined in children's urine and hair samples, and efforts were made to correlate them with dental fluorosis. Dental fluorosis and caries prevalence were examined in a total of 52 schoolchildren aged 7-15 years (29 boys and 23 girls). Fluoride levels in three types of samples were analyzed using composite fluoride ion-selective electrode. Results showed high prevalence of dental fluorosis (34.6 %) and low prevalence of dental caries (23.1 %, mean DMFT 0.96) among children exposed to wide range of water fluoride levels (0.11-4.14 mg/L, n = 27). About 11 % of water samples exceeded 1.5 mg/L, a drinking-water quality guideline value for fluoride given by the World Health Organization (2006). Fluoride levels in urine and hair samples ranged between 0.07-2.59 (n = 48) and 1.07-19.83 mg/L (n = 33), respectively. Severity of dental fluorosis was positively and linearly correlated with fluoride levels in drinking water (r = 0.79). Fluoride levels in urine and hair were strongly and positively correlated with levels in drinking water (r = 0.92 and 0.94, respectively). Fluoride levels in hair samples appeared to be a potentially promising biomarker of fluoride intake via drinking water on one hand, and severity of dental fluorosis on the other hand. Based on community fluorosis index value of 0.58, dental fluorosis revealed in Ritopek can be considered as "borderline" public health issue.

Fluoride subacute testicular toxicity in Wistar rats: Benchmark dose analysis for the redox parameters, essential elements and DNA damage.

Excessive fluoride (F-) levels in the environment could induce different pathological changes, including comorbidities in reproductive functions. Hence, the aim of the present in vivo study was to explore F- subacute toxicity mechanisms via Benchmark dose (BMD) methodology on rat's testicles. The experiment was conducted on thirty male Wistar rats for 28 days, divided into six groups (n = 5): 1) Control (tap water); 2) 10 mg/L F-; 3) 25 mg/L F-; 4) 50 mg/L F-; 5) 100 mg/L F-; 6) 150 mg/L F-. Testicles were dissected out and processed for the determination of F- tissue concentrations, redox status parameters, essential elements level, and DNA damage. PROASTweb 70.1 software was used for determination of external and internal dose-response relationship. The results confirmed a significant increase in superoxide anion (O2.-), total oxidative status (TOS), copper (Cu), zinc (Zn), iron (Fe), DNA damage levels, and decrease in superoxide dismutase activity (SOD1) and total thiol (SH) groups. The dose-dependent changes were confirmed for SOD1 activity and DNA damage. The most sensitive parameters were SOD1 activity and DNA damage with the lowest BMDLs 0.1 µg F-/kg b. w. Since human and animal populations are daily and frequently unconsciously exposed to F-, this dose-response study is valuable for further research regarding the F- health risk assessment.

[The application of air abrasion in dentistry].

One of the main objectives of contemporary dentistry is to preserve healthy tooth structure by applying techniques of noninvasive treatment. Air abrasion is a minimally invasive nonmechanical technique of tooth preparation that uses kinetic energy to remove carious tooth structure. A powerful narrow stream of moving aluminum-oxide particles hit the tooth surface and they abrade it without heat, vibration or noise. Variables that affect speed of cutting include air pressure, particle size, powder flow, tip's size, angle and distance from the tooth. It has been proposed that air abrasion can be used to diagnose early occlusal-surface lesions and treat them with minimal tooth preparation using magnifier. Reported advantages of air abrasion include reduced noise, vibration and sensitivity. Air abrasion cavity preparations have more rounded internal contours than those prepared with straight burs. This may increase the longevity of placed restorations because it reduces the incidence of fractures and a consequence of decreased internal stresses. However, air abrasion cannot be used for all patients, i.e. in cases involving severe dust allergy, asthma, chronic obstructive lung disease, recent extraction or other oral surgery, open wounds, advanced periodontal disease, recent placement of orthodontic appliances and oral abrasions, or subgingival caries removal. Many of these conditions increase the risk of air embolism in the oral soft tissues. Dust control is a challenge, and it necessitates the use of rubber dam, high-volume evacuation, protective masks and safety eyewear for both the patient and the therapist.

[Hard dental tissue minimal-invasive preparation using contemporary polymer rotating instruments and laser].

Goal of contemporary dentistry is to decrease the patient's discomfort during treatment. Dentists aim to achieve maximum with the newly developed dental materials as well as with new cavity preparation techniques in the shortest time span. Since the development of the first constructed borer (drilling machine) for caries removal, the preparation techniques have considerably changed. The progress of dental materials as well as the cavity preparation techniques has led us to contemporary carbide tungsten and diamond borers that are used with obligatory water cooling. The innovation within this field represents newly developed polymer borers that can detect the difference between carious lesions and healthy tooth structure. In this way the cavity preparation may be performed without damaging dental healthy tissue. This is possible owing to their hardness which is lower than the hardness of intact dentin. Polymer borer preparation is painless with less vibration, while the increase in temperature is negligible. Lasers have been used in clinical dentistry since 1980s so it can be said that they represent a new technology. The function of lasers is based on ablation which requires water. Erbium lasers have shown the highest potential with their ability to produce effective ablation of hard dental tissues. Laser application in dentistry requires special training as well as some protective measures. Laser advantages, compared to traditional preparation techniques, involve the absence of vibration, painless preparation, possibility of preparation without anesthetic and easier patient's adjustment to dental intervention which is of importance, especially in pediatric dentistry.

[The presence of early childhood caries among the members of different ethnic groups of the South Backa District].

BACKGROUND/AIM: Early childhood caries (ECC) is a special form of caries in primary dentition that affect teeth after eruption, with rapid progression, later symptomatology and numerous complications. The aim of this study was to investigate the frequency of ECC among different ethnic groups of preschool children in the South Backa District. METHODS: The survey was performed as a cross-sectional analytical study on the sample of preschool children of both sexes and different ethnic groups in the South Backa District. The diagnosis and the clinical form of ECC was defined by dental check-ups according to the modified Wyne's criteria: the initial form (type 1) shows carious lesions without disturbing the surface structure of the tooth enamel, the moderate form (type 2) shows carious lesions affecting one or two teeth or their surfaces, the middle form (type 3) shows carious lesions affecting more than two teeth or their surfaces, the severe form (type 4) shows the presence of two and more gangrenous roots in the maxilla intercanini sector, and the severe form with complications (type 5) shows the presence of two and more gangrenous roots in the maxilla intercanini sector with the presence of fistula and/or abscess of tooth root apex. Epidemiological data on the different ethnic groups were obtained by interviewing the parents of the examined children. The tests on significant statistical differences was performed by the variance analysis and chi2 test. RESULTS: The prevalence of ECC in children oped 41.32 +/- 8.57 months, of the South Backa District was 30.5%. The highest disease frequency was found in Roma children (50.0%) as well as in children of Ruthenian nationality (43.8%), than in children of Slovakia nationality (37.8%), Serbian (26.1%), Hungerian (25.4%) and other nationalities (27.4%). The frequency of types 1, 3, 4, and 5 ECC was twice as high as in children who do not speak Serbian language. CONCLUSION: The frequency of ECC occurence is different among ethnic groups. The highest frequency of ECC is present among the members of ethnic groups whose native language is not Serbian.

[Influence of social environment on caries prevalence in early childhood].

INTRODUCTION: Early childhood caries (ECC) is a special form of caries that affects decideous teeth with rapid progression and numerous complications. OBJECTIVE: The aim of the study was to define the prevalence of ECC in children of the South Backa area, the importance of social environment for the prevalence and severity of ECC, and define the model for its prevention. METHODS: The survey was the cross-sectional analytical study in the 10% sample of children, aged 13-64 months, different sex, social status and human environment. Severity and prevalence of ECC were assessed by dental check-ups. The epidemiological data were obtained by the interview of parents. The tests of significant statistical differences were performed by the analysis variance and chi2 (p < 0.05) test, as well as interdependence of ECC and single characteristics that could be a predictor of the disease by the logistic regression. RESULTS: The prevalence of ECC was 30.5%. The highest disease frequency was found in children of male sex (35.1%), out of kindergardens (54.2%), in the third and the next born child in the family (46.9%) and in part-time employed mothers (47.2%) who had only elementary education (59.3%) and were poorly informed about oral health. The highest prevalence (47.1%) of ECC was found in children whose parents had the lowest income per month. Type 1 of ECC was the most presented one (75.0%). CONCLUSION: The higher prevalence and more severe ECC were found in the third and the next born male child from rural environment.

Fluoride in drinking water and dental fluorosis.

In this study we determined the fluoride content in drinking water and hair of 12-year-old schoolchildren from different Serbian municipalities, i.e. Valjevo, Veliko Gradiste, Kacarevo and Vranjska Banja. The analyses were performed using composite fluoride ion-selective electrode. Average fluoride levels were 0.10, 0.15, 0.79 and 11 ppm in well water, 0.07, 0.10, 0.17 and 0.15 ppm in tap water, 19.3, 21.5, 25.4, and 32.5 ppm in hair samples, in Valjevo, Veliko Gradiste, Kacarevo and Vranjska Banja, respectively. Correlation analysis indicated statistically significant positive relationship between fluoride in wells water and fluoride in hair, for all municipalities: correlation coefficients were 0.54 (p < 0.05), 0.89, 0.97 and 0.99 (p < 0.001), in Vranjska Banja, Valjevo, Veliko Gradiste, and Kacarevo, respectively. Positive correlation was obtained also between fluoride in tap water and hair samples in all regions under the study, with statistical significance only in Valjevo municipality, p < 0.05. Dental examination of schoolchildren confirmed dental fluorosis only in the region of Vranjska Banja. Moreover, in endemic fluorotic region of Vranjska Banja, positive and statistically significant correlations were confirmed between fluoride in well water and dental fluorosis level (r = 0.61; p < 0.01) and additionally between fluoride in hair and dental fluorosis level (0.62; p < 0.01). The primary findings from this study have shown that fluoride content in hair is highly correlated with fluoride content in drinking water and dental fluorosis level, indicating that hair may be regarded as biomaterial of high informative potential in evaluating prolonged exposure to fluorides and to individuate children at risk of fluorosis regardless of the phase of teeth eruption.

Relationship between fluoride intake in Serbian children living in two areas with different natural levels of fluorides and occurrence of dental fluorosis.

The amount of fluoride present naturally in drinking water is highly variable, being dependent upon the individual geological environment from which the water is obtained. Chronic exposure to exceeding fluoride doses induces set of toxic effects, i.e. fluorosis. The aim of this study was to examine fluoride content in water and in the most frequently used vegetables, potato and bean, grown in two different Serbian regions, i.e. control region (Valjevo) and high naturally occurring fluoride region (Vranjska Banja), and moreover, to correlate estimated daily intake with dental fluorosis occurrence as an adverse effect of fluoride exposure of schoolchildren in Serbia. Study confirmed significant difference in fluoride content in water, potato and bean, consumed by 12-year-old children in two investigated municipalities. Results of the study indicated positive and statistically significant correlation between daily intake of fluoride and dental fluorosis level in the fluorotic municipality of Vranjska Banja (r = 0.61; p = 0.000017). Obtained relationship could be evaluated by means of binary logistic regression analysis, whereas probability for fluorosis occurrence could be predicted using the following equation: fluorosis occurence (%) = (34.852 x Cwater -12.644 x Cpotato - 9.362 x Cbean - 7.673) x 100 (Chi-Square (3) = 33.033; p < 0.001).