Association of characteristics of delivery and medical conditions during the first month of life with developmental defects of enamel.

BACKGROUND: Developmental defects of enamel (DDE) may be influenced by health problems and illness in children. The aim of the study was to identify the main characteristics of birth (delivery) and adverse medical conditions during the first month of life that may be related to DDE in permanent teeth. METHODS: 1000 schoolchildren between the ages of 9 and 11 years were selected for this cross-sectional study by multistage randomization from four educational zones in Shiraz in 2013. Intraoral examination was used to diagnose DDE according to World Health Organization screening guidelines and the Modified DDE Index. The data on seven birth factors as well as health and nutritional conditions during the first month of life were collected by a questionnaire completed by the parents, and were analyzed with the chi-squared test, Spearman's correlation and binary logistic regression. RESULTS: 469 (48.2%) out of 974 schoolchildren had at least one permanent tooth with DDE. The defects were significantly related with Apgar score at birth <7 (p = 0.003) and illness during the first month (p = 0.035). The frequency of DDE was significantly lower in the third child in families compared to the first and second child (p = 0.005). However, DDE showed no significant relationship with gestational age, delivery type, birth weight, gender or type of feeding during early infancy. CONCLUSIONS: Three associated factors were identified (birth Apgar score, illness during the first month of life, birth order) for DDE in permanent teeth. No specific illness was found to be significantly associated with DDE

Photographic Facial Soft Tissue Analysis by Means of Linear and Angular Measurements in an Adolescent Persian Population.

To obtain objective average measurements of the profile and frontal facial soft tissue to be used as a guide for aesthetic treatment goals. Methods and Materials : This observational study included 110 females and 130 males high school students aged 16-18 years. None of the subjects had any facial deformities. All of them and their parents gave consent to take part in this study. In each case, two standard photographs of profile and frontal views were taken 27 landmarks were digitized on photographs. The mean, standard deviation, and range for a total of 43 facial indices were calculated digitally by computer software. The Student's t-test was used to compare males and females. Results : The ratio between the lower and middle facial thirds was one to one, but the height of the upper facial third was proportionally smaller than the other two-thirds in both sexes. Boys had greater nasal length, depth, and prominence than girls with statistically significant differences. Both upper and lower lips were more prominent in girls than in boys. All measurements of the chin showed sexual dimorphism characterized by greater chin height and prominence and deeper mentolabial sulcus. Boys had greater facial dimensions than girls. Mouth width, nasal base width, and intercanthal distance were significantly greater in boys. Conclusion : The labial, nasal, and chin areas showed sexual dimorphism in most of the parameters used in this study. Boys had larger faces, greater facial heights, longer nasal, labial, and chin lengths, and greater nasal, labial, and chin prominence

An approximation algorithm for computing the visibility region of a point on a terrain and visibility testing

Given a terrain and a query point p on or above it, we want to count the number of triangles of terrain that are visible from p. We present an approximation algorithm to solve this problem. We implement the algorithm and then we run it on the real data sets. The experimental results show that our approximation solution is very close to the real solution and compare to the other similar works, the running time of our algorithm is better than their algorithm. The analysis of time complexity of algorithm is also presented. Also, we consider visibility testing problem, where the goal is to test whether p and a given triangle of train are visible or not. We propose an algorithm for this problem and show that the average running time of this algorithm will be the same as running time of the case where we want to test the visibility between two query point p and q

Gender similarity in low agreement between written and video ISAAC asthma questionnaires

Background and Aim. The prevalence of childhood asthma varies among different nations and appears to have increased in recent years. It has been difficult to determine this prevalence precisely and compare the communities due to the lack of a standardized method. The International Studies of Asthma and Allergies in Childhood (ISAAC) has developed a written and video questionnaire to measure asthma prevalence and overcome these difficulties. This study was carried out to determine the prevalence of childhood asthma in Kashan, the central area of Iran, and to assess the agreement between the ISAAC written and video questionnaires and its gender relationship. Methods. Between December 2002 and June 2003, 2533 school children, aged 13-14 years, in Kashan secondary schools completed sequentially the ISAAC written and video questionnaires. The agreement between responses to the two questionnaires for reported “ever wheeze”, “exercise wheeze”, “night wheeze” and “night cough” was determined, using kappa coefficient and concordance. Results. The prevalence of asthma symptoms were significantly lower in the responses to the video questionnaire compared with the written questionnaire. Kappa coefficient showed only poor to fair agreement (κ = 0.13- 0.24) between video and written questionnaires, although the concordance between them always exceeded 60%. Conclusions. This study showed that reported asthma symptoms based on video questionnaires were significantly lower than the written questionnaire, and that there is low agreement between the two questionnaires which requires further investigation to explain the findings. In addition, this investigation revealed no significant difference between the genders for this low agreement

A comparison of photographic, replication and direct clinical examination methods for detecting developmental defects of enamel

Different methods have been used for detecting developmental defects of enamel (DDE). This study aimed to compare photographic and replication methods with the direct clinical examination method for detecting DDE in children's permanent incisors