Introduction:The premature loss of primary teeth may reduce arch length required for the succeeding tooth and, hence, predisposes crowding, rotation and impaction of the permanent teeth. There are only limited studies carried out about the prevalence of early loss of primary teeth.Aim:The present study was performed to evaluate the prevalence of early loss of primary teeth in school children in Chidambaram town in Tamilnadu, India.Settings and Design:A total of 1121 school children (561 boys and 560 girls) between 5 and 10 years of age were selected for the study.Materials and Methods:An experienced examiner performed all clinical examinations under natural light. Data including age and missing tooth was collected.Statistical Analysis Used:Microsoft Excel/2000 (Microsoft Office XP) data spreadsheet was used and later exported to the Statistical Package for Social Science (SPSS) for Windows (version 10.0). Descriptive statistics was applied and, from the results, chi-square tests were applied at a level of significance of 5% (P < 0.05). Results and Conclusions: The results showed that 16.5% of the sample had early loss of primary teeth, but no differences were observed between genders (P > 0.05). The greatest prevalence was found among the 8-year olds (5.08%), and the most commonly missing teeth were the right lower primary first molars (16.82%). It can be concluded that the prevalence of early loss was high and that the lower primary molars were the most commonly missing teeth in the present study

Background:Dental caries is essentially a process of diffusion and dissolution. If the aspect of dissolution can be curtailed some degree of prevention can be achieved.Aims:The present study was carried out to evaluate and compare the effect of Er:YAG laser and Co2 laser irradiation combined with acidulated phosphate fluoride treatment on in vitro acid resistance of human enamel.Design:An in vitro study was carried out on 30 human premolars to evaluate the enamel's acid resistance using an atomic emission spectrometry analysis.Materials and Methods:A total of 60 enamel specimens were prepared from 30 human premolars and were randomly assigned to 6 groups: (1) Untreated (control); (2) 1.23% acidulated phosphate fluoride (APF) gel application alone for 4 min; (3) Er:YAG laser treatment alone; (4) Co2 laser treatment alone; (5) Er:YAG laser + APF gel application; (6) Co2 laser + APF gel application. The specimens were then individually immersed in 5 ml of acetate buffer solution (0.1 mol/L, pH 4.5) and incubated at 37°C for 24 h, and the acid resistance was evaluated by determining the calcium ion concentration using the atomic emission spectrometry.Statistical Analysis:An ANOVA model was constructed (P value of 0.05), followed by Tukey's test for multiple pair wise comparisons of mean values.Results:Significant differences were found between the control group and the test groups (P < 0.001).Conclusions:Combining acidulated phosphate fluoride with either Er:YAG or Co2 laser had a synergistic effect in decreasing the enamel demineralization more than either fluoride treatment or laser treatment alone.

Aim:The aim of the present study was to estimate and compare the microleakage of a pit and fissure sealant after etching and Er:YAG laser treatment.Materials and Methods:Twenty non-carious premolars extracted for orthodontic reasons were equally divided into two groups. Samples in Group- I were treated with 37% phosphoric acid. Samples in Group II were irradiated with Er: YAG laser at 400 mJ at 4 Hz. Sealant was placed and light cured. Then, the samples were subjected to thermocycling. The samples were then immersed in 1% methylene blue. The samples were sectioned and examined under stereomicroscope at ×10 magnification.Results:Acid etched samples showed significantly less microleakage when compared to laser etching and it was statistically significant (P<0.01).