Prevalence of fluorosis in 5-12 year-old children in the north-western villages of Makoo in 2004

Fluorosis is defined as a sort of enamel hypocalcification. Clinical features of fluorosis vary from thin white lines on the enamel to chalky and opaque enamel. The enamel may be destroyed after tooth eruption. Various prevalence rates have been reported in different populations. Major contributing factors are temperature, altitude and hygienic trends. The aim of this study was to evaluate the prevalence and severity of fluorosis in 5-12 year-old children in the North-Western villages of Makoo. A total of 58 children aged between 5 and 6, and 421 students aged between 7 and 12 from the North-Western villages of Makoo were selected. Dean Index was used to evaluate the prevalence of fluorosis in the primary and permanent dentition. To compare the severity of fluorosis in the maxilla and mandible and also to assess the coordination rate of fluorosis in the left and right sides of the jaw, TF Index was used. TSIF was used to compare fluorosis rate in different tooth surfaces. Discoloration prevalence and rate were compared between maxillary and mandibular incisors. Chi-square test and t-test were used to analyze the results. Fluorosis rate in the primary and permanent dentition was 100%. According to TF Index, the highest coordination rate was observed in mandibular incisors and the least was observed in maxillary second molars. The difference in the severity of fluorosis between maxilla and mandible was statistically significant [p < 0.05]. Discoloration rate increased in maxillary central incisors with age. Very high prevalence rate of fluorosis in the primary and permanent teeth in the North-West of Makoo revealed a major regional problem; therefore, preventive strategies such as informing people of improper use of fluoride-containing supplements and reduction of the fluoride content of drinking water are suggested

Contamination of dental unit water and air outlets following use of clean head system and conventional handpieces

Dental handpiece is a source of contamination because it is in constant touch with the oral cavity. Sterilization does not seem to be sufficient to prevent penetration of microorganisms into air and water lines of the unit, because negative pressure developed by valves [which are placed in water outlets] and post shut-off inertial rotation of handpiece result in water and debris being sucked into air and water outlets of dental unit. The aim of this study was to compare dental unit contamination following use of clean head system handpieces and conventional handpieces. Twenty-two dental units in the Department of Pediatric Dentistry in Shahid Beheshti Faculty of Dentistry were used for the purpose of this study. A 1.5x10[8] cfu/mm[3] concentration of Staphylococcus epidermis [SE] was used to contaminate the air and water outlets of dental units. Ten clean head system handpieces and 10 conventional handpieces were used for 30 seconds in the above-mentioned suspension. Microbial samples were collected from the air and water lines. Culturing and colony counting procedures were carried out. Data was analyzed by t-test; a value of p < 0.01 was considered significant. demonstrated a significantly lower SE contamination in water outlets following the use of clean head system [p < 0.01]. A lower tendency of clean head system handpieces to transmit SE compared to conventional system makes them a better choice for infection control