Contamination of a dental unit water line system by Legionella Pneumophila in the Mashhad school of dentistry in 2009

Dental unit waterline system is considered potential source for contamination with Legionella species. The aim of this study was to determine if contamination of a dental unit water line system by Legionella pneumophila serogroup1 in the Mashhad School of Dentistry occurred in 2009. A total of 52 dental units were selected from all clinical departments of the Mashhad School of Dentistry. Samples of water were collected from outlets of water/air spray, high-speed dental hand pieces and water cup fillers. Samples were tested via the ELISA method. At the beginning of the work day, a total of 36.1 percent of dental units were contaminated by Le-gionella pneumophila serogroup 1. Infection control of the dental unit water line system regarding legionella in the Mashhad School of Dentistry is a challenge and engineering controls should be used in contaminated clinics

Prevalence and pattern of congenital missing teeth in a group of Iranian adolescents

Congenital missing tooth in the condition of having genetically one or more missing teeth which cannot be observed clinically or in radiographic images. This is one of the most prevalent anomalies in dental development that occurs either individually or as symptoms of a syndrome. Moreover, for permanent teeth, it is common with a reported prevalence of between 1.6-9.6%. The aim of this study was to assess the prevalence rate and the pattern of congenital missing teeth in adolescents referring to Mashhad School of Dentistry. In this cross-sectional study, a total of 600 panoramic radiographs related to the subjects aged 9-14 years [351 girls and 249 boys] were analyzed. The data were recorded in the related forms, and the analyzed using Chi-square and Exact rests. Among 600 panoramic radiographs, 94 teeth were found to be missing. The most and the least frequent missing teeth were the mandibular second premolars and the maxillary central incisors [observed in only 1 subject], respectively. The most commonly absent teeth were the mandibular second premolars, the mazillary lateral incisors, the mandibular central incisors, and the maxillary second premolars in order of the frequency. This study revealed that the frequency o missing tooth in girls to higher than that in boys. Thus, due to the girls' more aesthetic sensibility and also intricate treatment of such anomaly, accurate and frequent examination of adolescents' particularly girls' teeth for on-time diagnosis is crucial

[Dental treatment needs of 6-12-year old children in Mashhad orphanages in 2006]

Since the health of children living in orphanages is related to the health policies implemented in those centers, evaluation of their health status, at least annually, can reveal the shortcomings and help to correct them. The purpose of this study was to determine dental treatment needs in 6-12-year old children in Mashhad orphanages. This cross-sectional descriptive study was carried out on all 6-12-year old children [137 children] in Mashhad orphanages. Prevalence and severity of dental caries [using DMFT/dmft index], dental treatment need [using UTN index], gingival health status [using MGI index], and oral health status [using PI index] were evaluated. The data were analyzed using chi-square, and Mann-Whitney tests. 42% of children were male and 58% were female. 73.7% and 43.8% of children had some types of treatment needs in their primary and permanent teeth respectively. The mean DMFT was 1.37 +/- 1.61 [1.38 +/- 1.64 in girls and 1.36 +/- 1.57 in boys]. The mean dmft was 3.4 +/- 2.7[3.2 +/- 2.47 in girls and 3.61 +/- 3.0 in boys]. 57.2% had poor oral health status [PI index]. 67% had moderate and severe gingivitis [MGI index]. caries experience, especially in primary dentition was high in terms of prevalence and severity and most of the children had some types of treatment need. Effective oral health promotion strategies need to be implemented to improve the oral health of children living in orphanages

[Evaluation of oral health knowledge, attitude and behaviour of employees in Mashhad Health Centers No 1, 2 and 3 in 2006]

Health is the base for Development and also health level is affected by the development. Through Culture Promotion attracting Public cooperation, we can change their knowledge, attitude and behaviour about oral and dental health. This study aimed at determining the level of knowledge, attitude and behaviour among staff of health and treatment centers No1, 2 and 3 of Mashhad city about oral and dental health. This research was a descriptive cross-sectional study. This study was conducted on 186 staff of health centers in the city of Mashhad who had been selected through multistage sampling. After completing of the questionnaires by the staff, the data were collected and then analyzed by Kruskal Wallis statistical test. This study showed that among the 186 cases studied, 23.1% had good knowledge and 19.9% had poor knowledge about oral and dental health, while only 2.2% had good attitude and 9.2% of the cases had good behaviour. This study showed that the level of knowledge about oral and dental health had a statistically significant relationship with educational level [P=0.004], so that the dentists had the highest level of knowledge and the technicians had the lowest level. This study revealed that among these three health centers in Mashhad, health center No 2 staff had the lowest knowledge level. According to the low knowledge, attitude and behavior of the staff of the health centers No 1, 2 and 3, establishment of strategies for continuous education courses seems necessary

[ effect of different surface treatments of stainless steel crown and different bonding agents on shear bond strength of direct composite resin veneer]

Stainless steel crown [SSC] is the most durable and reliable restoration for primary teeth with extensive caries but its metalic appearance has always been a matter of concern. With advances in restorative materials and metal bonding processes, composite veneer has enhanced esthetics of these crowns in clinic. The aim of this study was to evaluate the shear bond strength of SSC to composite resin using different surface treatments and adhesives. In this experimental study, 90 stainless steel crowns were selected. They were mounted in molds and divided into 3 groups of 30 each [S, E and F]. In group S [sandblast], buccal surfaces were sandblasted for 5 seconds. In group E [etch] acidic gel was applied for 5 minutes and in group F [fissure bur] surface roughness was created by fissure diamond bur. Each group was divided into 3 subgroups [SB, AB, P] based on different adhesives: Single Bond, All Bond2 and Panavia F. Composite was then bonded to specimens. Cases were incubated in 100% humidity at 37°C for 24 hours. Shear bond strength was measured by Zwick machine with crosshead speed of 0.5 mm/min. Data were analyzed by ANOVA test with p<0.05 as the limit of significance. There was no statistical interaction between surface treatment and adhesive type [P>0.05] so the two variables were studied separately. No significant difference was observed in mean shear bond strength of composite among the three kinds of adhesives [P>0.05]. Similar results were obtained regarding surface treatments [P>0.05]. Based on the results of this study, treating the SSC surface with bur and using single bond adhesive and composite can be used successfully to obtain esthetic results in pediatric restorative treatments

[Goiter surgery and urinary iodine concentration in 7-10-year-old children, Azarbayejan-Gharbi Province, 2001]

Iodine deficiency disorder [IDD] is a worldwide health problem. Parts of Iran, such as Azarbayejan-Gharbi, had been known as endemic areas for goiter. IDD was accepted as a priority health problem in our country and a National IDD Council was formed in 1989. This study was performed to evaluate the National IDD Council program in 2001 among 7-10-year-old children in Azarbayejan-Gharbi province. In this cross sectional study, 1200 children [M/F ratio=1], aged 7-10 years, were selected and grading of goiter was performed in accordance to the WHO criteria. Urinary samples were obtained from 120 children and urinary iodine was measured using digestion method. Total prevalence of goiter was 7.2% [6.7% in girls and 7.8% in boys]. The median urinary iodine was 14.6microg/dl. 83.9% had urinary iodine of more than 10microg/dl, while 2.6% had urinary iodine levels of < 5microg/dl. None of the candidates has urinary iodine of less the 2microg/dl. There was no significant difference between sexes and urban or rural areas. Results have revealed that the total prevalence of goiter has significantly decreased among children in Azarbayejan-Gharbi province, meanwhile, urinary iodine concentration of children has reached to WHO approved rate. Thus, Azarbayejan-Gharbi province could be classified among "iodine-deficiency-free" areas in Iran

[Radiogrphic evaluation of third molar developmental stages in a group of Iranian children and adolescents]

Basically as a matter of fact, it is important to determine the status of third molars before many of the children's dental treatment. The pattern of development and growth of face, jaw and teeth differs from race to race. Therefore, studies on the third molar status in each population seem to be an important issue. This study was performed to determine the pattern of the third molar development in a group of Iranian children and adolescents, in order to province a suitable reference for clinical use and future studies. In this descriptive study, 757 panoramic radiographs of patients, 6-16 years old, were investigated and the development of the third molars was categorized based on nine stages. The data were analyzed with chi-square and paired samples tests. The most important results of this study were: 1. The earliest and latest ages with the possibility of observing the signs of wisdom tooth crypt in panoramic radiographs, were six and 14 years respectively. 2. Among the investigated ages, the highest possibility of observing finding the first sign of third molar crypt emergence was found to be at the age of nine. 3. Possibility of the third molar existence after age of 10 reduces about 53% in comparison to the earlier ages. 4. There was a significant difference between age and the third molar developmental stage in each four quadrant [p=0.000]. Determination of the pattern of third molars development stages is useful in clinical diagnosis and comprehensive treatment plan

[ prevalence study of traumatic dental injuries in male Athletes in non martial sports in Mashhad in 2001]

In our country were the youth form a high percentage of the population and we can observe their growing presence in athletic fields, the study of prevalence of traumatic dental injuries and the ways of preventing them seems necessary. The purpose of this study is to specify the rate of prevalence of traumatic dental injuries caused by non- martial sports in the city of Mashhad. In this cross-sectional study, 409 male athletes from 12 gyms [both professional and non- professional] in Mashhad were examined for traumatic dental injuries in 3 kinds of non-martial sports [wrestling, football and basketball] through a questionnaire containing data about their athletic backgrounds. Statistical analysis was made by Ep16 software and was analysed using X2 statistical test. 1. Out of the total number of those examined 33% had traumatic dental injuries. 2. The highest rate of injuries was related to the upper jaw dental injuries [75.2%] central incisors [60.5%] and the incisal third [26.1%]. 3. Out of all those having traumatic dental injuries 24.7% had referred for comprehensive treatment. Considering high rate of prevalence of dental injuries among athletes [33%] and with regarded to the outcomes caused by not having proper and timely treatment, it seems necessary to instruct sports coaches sanitary instructors of schools, and the athletes about the importance of using mouthguards and the early treatment of dental injuries

[Evaluation of oral and dental health status in major thalassemia patients referred to Dr. Sheikh Hospital in Mashhad in 2002]

The thalassaemias, a heterojenous group of inherited disorders, are caused by deficient synthesis of one or more of the chains of human haemoglobin. Oral-facial manifestations such as maxillary protrusion, severe malocclusion, marked openbite, saddle nose, protrusion of upper lip and glossitis are seen in thalassemia. In this cross-sectional descriptive study, 165 patients, consisting of 97 boys and 68 girls who supported by thalassemic society were examined. Study variables were age, sex, dental caries and gingival status. Data were analyzed by Chi-square, T test and variance analysis. Mean DMFT index was 3.6+/-0.2, and the maximum belonged to more than 18 year old children [6.31+/-3.28]. DMFT=0 and dmft=0 was found in 28.2% and 34.4% respectively. In relation to gingival status 33% had gingivitis, 1.8% had periodontitis and 64.8% normal gingival. According to the high incidence of caries and gingivitis in thalassemic patients need to be encouraged for effective preventive measures, education and dental treatment for this high risk group

[Evaluation of oral health status amongst 6-7-year-old children in Mashhad in 2001]

Dental caries is a major problem in dentistry. Although we have observed a decline in caries prevalence for many years, it is clear that dental caries still remains the most prevalent disease afflicting humans. The objective of this study is evaluation of oral health status amongst 6-7-year-old children in Mashhad. This cross-sectional descriptive study was performed on 1938, 6-7-year-old preschool children in Mashhad to determine dmft index. T student and Chi-square tests were used for analytical analyze. The mean of dmft in all children was 4.72 +/- 4.18, and there was not a significant difference between girls and boys. Results showed that a significant number of primary teeth were caries. The maximum mean of dmft was seen in teeth D and E. 55.1% of boys and 56.3% of girls had caries in the first primary molars. 59% of boys and 58.1% of girls had caries in the second primary molar. Also 24.7% boys and 22.9% of girls had dmft=0[caries free], and 14.6% boys and 13.5% of girls suffer from rampand caries [dmft>10]. Successful management of the dental caries problem demands,a comprehensive preventive program, regular recall appointment for maintenance work and reemphasis of the preventive procedures

in - vitro study on the effect of Iranian soft drinks on enamel microhardness of primary teeth

Diet is the most important etiologic factor in dental erosion. Erosion of dietary origin in children is frequently related to carbonated drinks and acidic foods. The aim of this study was to evaluate the effects of some acidic soft drinks on enamel micro-hardness of primary teeth. This interventional in vitro study was performed on 40 healthy deciduous teeth. Enamel blocks were prepared and were polished on their external surfaces using water and sand paper. The baseline hardness was measured using Vickers microhardness measuring apparatus. The enamel blocks were then immersed in 20[cc] Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt-drink for 5 and their microhardness was assessed. The data were analyzed using co-variance and paired sample t-tests. The baseline hardness in primary teeth, was 378.4 +/- 31.65 [kg/mm[2]] for Coca Cola, 373.57 +/- 30.31 [kg/mm[2]] for Zam Zam, 378.38 +/- 21.92 [kg/mm[2]] for Pepsi and 385.43 +/- 34.79 [kg/mm[2]] for Ab-Ali yoghurt-drink, before being placed in the experimental soft drinks, After immersion [second hardness], these values decreased to 333.02 +/- 32.15 [kg/mm[2]], 339.65 +/- 20.91 [kg/mm[2]], 342.27 +/- 28.01 [kg/mm[2]] and 341.46 +/- 32.34 [kg/mm[2]] for Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt soft drinks, respectively. The reduction in microhardness was statistically significant for each of the tested soft drinks but a statistically significant difference was not observed between the study groups. The intake of soft drinks such as Coca Cola, Zam Zam, Pepsi and Ab-Ali yoghurt-drink can reduce enamel microhardness in primary teeth

[Evaluation of urinary fluoride excretion following NaF mouth rinse prescription in 6-12 years old children]

Sodium fluoride mouthrinses have been effective in preventing caries in numerous clinical trials during the past 50 years. The purpose of this study was to asses the oral retention, or ingested and urinary excretion of fluoride with the use of Naf mouthrinse. 45 school children at the ages of 6 to 12 years at a day and night [residential] nursery were selected. The amount of fluoride in their drinking water was about 0.2ppm. At the first part of study, before using mouthrinse children were instructed to brush their teeth at bedtime with non fluoride dentifrice. The salivary specimens were gathered the same night after brushing, but specimens from the urine were gathered the next morning. In the second part, the same specimens were taken after using the 0.2% Naf mouthrinse [1 minute with 5ml]. The difference between amount taken orally and the one not recovered in the expectoration is amount of fluoride retained orally and potentially ingested. Fluoride concentration in the urine and saliva was measured by means of potentiometer device. The data were analysed by the statistical package of Graphpad instat and using paired sample t.test, and analysis of variance. The numerical values are shown as mean +/- sd. The fluoride retained during mouthrinsing ranged from 1.07 to 2.42mg F, with the average of 1.7 +/- 0.32mg F. The amount of F excreted before and after mouthrinsing was 110.56 +/- 40.46 microg and 201.27 +/- 70.45 microg respectively. The urinary fluoride excretion rate before and after mouthrinsing was 13.87 +/- 5.05 and 24.68 +/- 9.35 respectively. These results indicated that more than 1/3 of the applicated solution is orally retained or potentially ingested. There was significant difference between the amount of urinary fluoride excretion rate before and after mouthrinse application [P<0.0001]. Amount of fluoride existing in fluoride mouthrinse might be swallod and ingested, therefore necessary caution should be consider inorder to recommend this fluoride regimen in school children. The potential ingestion may be considered unimportant, but since there are many other sources of fluoride such as dentifrices, fluoride accumulation may be a cause of increasing the fluorosis risk. So, training and teaching school personel about proper use of mouthrinse is of great priority

[ comparative study of fracture strength of pulpotomized primary molars after restoration with compomer and composite]

Maintenance of primary teeth has a special importance for development of occlusion and arc stability. Primary teeth which have lost a lot of tooth structure are restored routinely with stainless steel crowns-Bonded restorations reinforce the remnant structure of tooth and increase the fracture strength. The purpose of this study was to determine the fracture strength of pulpotomized primary molars after restoring with Coremax II and Compoglass. In this parallel in vitro interventional study, 60 extracted second primary molars, were selected. After the teeth were mounted in self-curing acrylic resin, the standard pulpotomy was performed. The teeth were divided into 3 groups of 20. Group A was restored with Coremax II, group B with Compoglass and group C [control] with amalgam. All groups were subdivided into 2 subgroups for load cycling Subgroups a[1], b[1] and C[1] were regarded as baseline without load cycling. Subgroups A[2], B[2] and C[2] were loaded for a period of 5 days load cycling. After that, the specimens were placed in Incubator for 24 hours. Finally all groups were fractured in the Instron Machine. compressive test was performed with the round Cross head speed of 5-mm/min. All specimens were examined for type of fracture [adhesive, cohesive] with use of a steriomicroscope [xl6]. Quantitative data analysis was done using ANOVA and Duncan's test with a 95% significance level. Chi-square test was performed for evaluation of kind of fracture. There was an interaction between two factors of time and material [P<0.05]. The time interval had a significant effect on mean fracture strengths of Coremax II and amalgam [P<0.05]. The most fracture strength was observed at base line. Kind of material had a significant effect on fracture strength. At baseline, Compoglass had the least mean fracture strength [97.19 kg] and Coremax II had the greatest one [131.39]. After 5 years there was no significant difference in fracture strength between amalgam and Compoglass, but the fracture strength of Coremax was significantly higher than the others [P<0.05]. There was a correlation between kind of fracture and material. In amalgam, 100% of fracture was of adhesive and in Compoglass, 60% of cohesive type while in Coremax II, 85% of the fracture was of adhesive type. According to this study and because of high fracture strength of teeth restored with Core max II, this material is an acceptable restoration material just for restoration of pulpotomized primary molars

Frequency of oral lesions in newborns at Mashhad Imam Reza Hospital, in 2001

Neonatal period is the first developing phase after birth follow by different developmental processes up to the age of puberty. A neonate may be born with different oral lesions. The aim of this study was to evaluate oral lesions in newborns at Mashhad Imam Reza Hospital. In this cross - sectional descriptive study, 600 newborns were observed during 2.5 months in 2001. Total oral cavity including soft palate, hard palate, tongue, alveolar ridge and oral cavity floor was examined with tongue blade and light. Results showed that 52.6% of newborns [316 cases] had oral lesions. 0.66% cases had natal and neonatal teeth, 0.5% cases had congenital epulis, 1.8% cases were with ankyloglossia, 41.5% cases with Epstein's pearls, 22.3% cases with Bohn nodule and 0.16% case with exostosis. There were no cases with cleft lip or cleft palate. The most frequent oral lesion observed was Epstein's pearls. Our study showed that prevalence of natal teeth in the city of Mashhad was more than other countries except for Bohn nodule and Epstein's pearls which occurred less frequently than other countries