ABSTRACT
Background. Fluoride-releasing capacity has been added to fissure sealants to benefit from the positive anticariogenic effects of both sealants and fluoride. This comparative research investigated the inhibitory effects of conventional and fluoridereleasing fissure sealants on initial lesions with or without exposure to fluoride toothpaste. Methods. Cavities were prepared on buccal surfaces of 24 premolar teeth which were randomly divided into three groups. In the cavities of the first group, a fluoride-releasing fissure sealant and in the second group, a conventional fissure sealant were placed; the third group was left intact. Incipient lesions were produced around the cavities. Each group was divided into two subgroups, which were exposed to fluoride-containing toothpaste or artificial saliva. Lesion depths were measured under a polarized light microscope before and after treatment. Changes in lesion depths in the samples were analyzed by SPSS 17. Results. Initial and final caries depths were significantly lower in the fluoride-releasing fissure sealant group compared to the other groups (P<0.001). The average depths of carious lesions were lower in subgroups exposed to fluoride-containing toothpaste than the subgroups exposed to artificial saliva and the difference was significant in the conventional sealant group and the group without sealant (P<0.001); however, the difference between the toothpaste-exposed and saliva-exposed subgroups was not significant in the fluoride-releasing fissure sealant group (P=0.721). Conclusion. Incorporation of fluoride into the fissure sealants can be effective in the inhibition of dental caries. It seems that fluoride, released from fluoride-releasing sealants, overwhelms the remineralizing capacity of fluoride released from the toothpaste on the same tooth.
ABSTRACT
Background. Diode lasers (DLs) have demonstrated equal or better desensitizing effects than fluoride varnish, 10% potas-sium nitrate (NK) gel and Gluma. The current study evaluated the desensitizing effect of combined application of DLs with two different output powers and compared it with single DL therapy. Methods. Sixty-two hypersensitive teeth were allocated randomly into two groups: the single group was treated with 3-W DL beam once and in the combined group, the teeth were irradiated three times (the first time with 0.2-W and then with 3-W and the second and third times, 48 and 96 hours after the baseline visit, with 0.2-W DL beams). The amount of dentin hyper-sensitivity (DH) was evaluated, immediately before and after each visit, and 1 week and 1 and 3 months after the first visit. Data analysis was performed using chi-squared test, repeated measurement of ANOVA and Mann-Whitney U test. P<0.05 was considered statistically significant. Results. Statistically significant changes were observed in the means of VAS indices between all the measurement intervals and pretreatment measures, in both experimental groups (P<0.001). The difference in VAS reduction among the groups was not significant when the hypersensitive teeth were stimulated by a periodontal probe and a jet of air (P=0.63 and P=0.12). Conclusion. The results of the present study showed that using both high-intensity and combined DL beams gives rise to significant reductions in DH. There was no significant difference between combined and single laser therapies in the treatment of tooth hypersensitivity.
ABSTRACT
PURPOSE: This study aimed to determine the average eruption time and sequence of permanent teeth in patients with cerebral palsy (CP) and to compare the results with the established norms for Iranian subjects. METHODS: This cross-sectional study comprised of 207 individuals with CP, 96 boys and 111 girls, ranging from 6 to 19 years. The average age at eruption of permanent teeth, excluding third molars, was given as the mean (± SD) and median in years for each gender. A table of percentiles of the eruption time was also determined. Comparisons were made using t-test at a significance level of 0.05. RESULTS: The sequence of eruption in children with CP was almost similar to the normal. With the exception of the second premolar and the second molar, tooth eruption was advanced in girls compared with boys. There was no difference between the left and right sides of each arch. Mandibular teeth had an earlier eruption time than maxillary teeth except for the second premolar. In general, eruption times of children with CP were later (1-33 months) than those reported previously for healthy children. CONCLUSIONS: Despite the almost similar sequence of eruption, a high tendency to delayed eruption of permanent dentition was observed in children with CP.
Subject(s)
Cerebral Palsy/physiopathology , Dentition, Permanent , Tooth Eruption , Child , Child, Preschool , Female , Humans , MaleABSTRACT
BACKGROUND AND AIMS: As a result of poor quality of public water supply in many countries, people have recently turned to bottled water consumption, the fluoride content of which is not generally consistent among different brands. This study sought to measure the fluoride concentration of public water supply in comparison with commercial brands of min-eral bottled water available in Tehran, Iran. MATERIALS AND METHODS: Eight different brands of locally produced bottled mineral water and samples of tap water were evaluated for fluoride content. All samples were collected in five equal containers in two summer and winter seasons. The fluoride content in part per million (ppm) was determined using a fluoride Ion Selective Electrode. The data were ana-lyzed using two-way ANOVA. For comparison of the fluoride content between three different brands of bottled water, one-way ANOVA was employed. Sample t-test was used to compare the label and laboratory values of bottled water. RESULTS: The highest concentration of fluoride in a bottled water brand was found to be 0.409 ppm with a pH of 6.67 in summer. There was a significant difference between the mean fluoride level of tap water (0.229 ± 0.079 ppm) and bottled water (0.111 ± 0.122 ppm) (P < 0.001). The measured fluoride concentrations of bottled water were significantly lower than those printed on the labels (P < 0.001). CONCLUSION: Our findings revealed that the mean fluoride level of both bottled and tap water samples evaluated is con-siderably lower than accepted standards.
ABSTRACT
PURPOSE: The authors conducted an in vitro study to evaluate the shear bond strength of a fissure sealant to enamel pretreated with erbium,chromium:yttrium, scandium,gallium,garnet (Er,Cr:YSGG) laser or air abrasion followed by acid etching. METHODS: The authors sectioned extracted sound premolars mesiodistally and used the buccal and lingual surfaces for experimental analysis. They divided specimens randomly into three groups of 15 each according to the enamel surface pretreatment methods: group A, 37 percent phosphoric acid; group B, air abrasion followed by acid etching with 37 percent phosphoric acid; group C, irradiation with Er,Cr:YSGG laser followed by acid etching with 37 percent phosphoric acid. After applying a bonding system, the authors bonded cylinders of sealant to the enamel surfaces by using transparent gelatin tubes (0.7 millimeter in diameter and 1 mm in height) and then polymerized them. They stored all specimens in distilled water at 37 degrees C for 24 hours. They tested shear bond strength by using a universal testing machine with a crosshead speed of 0.5 mm per second. The authors analyzed the data by means of one-way analysis of variance and Tukey-Kramer post hoc tests (alpha = .05). RESULTS: The bond strength of group B specimens was statistically higher than those of group A and group C specimens (P < .05). The authors found no statistically significant differences in shear bond strength between surfaces treated with Er,Cr:YSGG laser and those treated with acid etching alone (P > .05). CONCLUSION: Pretreatment of enamel surfaces with air abrasion increased the bond strength of fissure sealant, but pretreatment with Er,Cr:YSGG laser did not increase the effectiveness of conventional acid etching of enamel in sealant bonds.
