[ effect of the number of clinical bracket points on the accuracy of curve fitted to dental arch form by 3D method]

Adjustment of an accurate curve to the dental arch is an important part of orthodontic treatment. Our goal was comparing the fitting accuracy of two curves constructed by different numbers of clinical bracket points [CBP] to the dental arch form using 4[th] degree polynomial function. A mathematical formula associated with a polynomial function was used to reconstruct the dental arch forms of 18 adolescents [18 casts] with normal occlusion. CBPs were marked on every tooth present in each maxillary and mandibular model [second molar to second molar] using an orthodontic bracket positioning gauge. A coordinate measuring machine [CMM] was used to record the coordinates of each CBP [x, y]. Then a curve fitting software was used to obtain the best 4[th] degree polynomial function and the associated curve fitted to all 14 CBPs. Another polynomial 4[th] degree function curve was obtained for the same models using CBPs only on central incisors, canines and second molars. Curves for each model were compared using statistical values including correlation coefficient, standard error, sum of residuals and R[2]. The mean root squares for curves fitted to 14 points in all samples were 0.8855 and it was 0.9629 when 6 points were compared with 14 points. The intraclass correlation coefficient [ICC] between curves fitted to 6 and 14 points was 0.946 in mandible, 0.983 in maxilla and 0.969 for both. Six CBPs were enough for proper fitting of 4th degree polynomial function to dental arch forms of both jaws

[Comparison of linear dimensional changes of two heat-cure acrylic resins]

Although acrylic resin materials have great features for making artificial dentures, but still dimensional change is a common problem in processing them. The aim of this study was to compare the linear dimensional changes of two heat-cure acrylic resins. In this descriptive study, twenty specimens in two groups were made by "Acropars" and "Meliodent" acrylic resins according to the manufacturer's recommendations in a metallic mold. Dimensional changes were measured at one, thirty and sixty weeks after processing with a digital caliper. The results were analyzed using T-test, T-paired test and repeated measure ANOVA. Considering the dimensional changes, there was a difference in the first day equal to 0.42 +/- 0.28 mm, in day thirty: -0.09 +/- 0.42 mm, and in day sixty: 0.07 +/- 0.22mm between the two acrylic resins, showing no statistically significant differences [p=0.21]. However, there were significant differences between different times of measurements [p=0.001]. "Meliodent" acrylic resin had more dimensional stability when compared to "Acropars" resin but there was not any significant difference between the two acrylic resins in the day sixty. There were significant differences between different times of measurements; the maximum difference between these two types of acrylic resins was in first day after polymerization

10 year survey on childhood CNS tumors

Tumors of the central nervous system constitute the largest group of solid neoplasms in children and are second only to leukemia in their overall frequency during childhood. The main purpose of the present study is to determine the incidence, age, sex, location and histological diagnosis of CNS tumors in children, less than 15 years of age, in the Mofid Children's Hospital, in the past 10 years. In this descriptive retrospective study we reviewed the medical records of 143 children with diagnosis of CNS tumors admitted during the past 10 years in neurology and surgery departments of Mofid Children's Hospital between the years 1996 and 2006. During the 10 year study period, CNS tumor was diagnosed in 143 patients; of these tumors, 119 were intracranial and 58 were intraspinal; 51.3% of brain tumors were located in the supratentorial and 48.7% in the infratentorial regions. The most common intracranial neoplasms were astrocytic tumors [36.8%], embryonal tumors [31.1%] and ependymal tumors [13.4%]. Of the intraspinal neoplasms the most frequently noted were embryonal tumors [37.5%], mesenchymal meningothelial tumors [20.8%], followed by astrocytic tumors [16.7%]. The median age at diagnosis was 8.9 +/- 4.1 years with a male to female ratio of 1.4:1 [P<0.5]. The most common intracranial astrocytic and embryonal neoplasms were pilocytic astrocytoma and medulloblastoma/ PNET respectively. Brain tumors in children constitute a diverse group in terms of incidence, distribution and histopathological diagnosis

[Relationship between occupational exposure and concentration of some trace elements in radiology and radiotherapy workers]

Investigating the chronic radiation effects in radiotherapy workers requires consideration of those parameters in which any small changes could result in profound effect on biological system. In this regard, body trace elements are believed to have important roles. To assess the biological effect of occupational exposure on blood trace elements concentrations. This was a case-control study performed at Isfahan University of Medical Sciences in 2006. Fifty radiotherapy workers were selected as case group and an equal number of hospital staff with similar social class and no radiation exposure as control group. Blood samples were collected from all members of two groups followed by determination of serum content of trace elements including copper, iron, zinc and magnesium. The data were analyzed using variance and regression tests. The mean concentrations of copper, iron, zinc and magnesium in technician group were 1.026 +/- 0.287, 1.052 +/- 0.185, 0.768 +/- 0.143, 21.112 +/- 1.272 and in control group 0.903 +/- 0.208, 1.00 +/- 0.134, 0.872 +/- 0.156, and 21.105 +/- 1.372, respectively. Values obtained for copper in technicians group were found to be higher than those of control group [p<0.02]. Zinc concentration was shown to be significantly lower in female technicians [p<0.03] than in males. No significant difference was found for magnesium or iron between two study groups. Based on data found in present study, the likelihood of the idea that chronic exposure to radiation could affect the concentration of body trace element is highlighted

effect of occupational therapy on negative symptoms of schizophrenia

Nowadays, schizophrenia is one of the most important disabling mental disorders in the world. Regarding to occupational therapy as one of the most essential treatment for this disorder, the main aim of this study is to determine the effect of it on negative symptoms of schizophrenias patients. This study is a clinical trials research and the samples were 84 schizophrenia patients of psychiatric ward of Farabi hospital in Isfahan. Sampling method was convenient and the samples were divided in to two interventional and control group randomly. The data collecting tool was scale for assessment of negative symptoms [SANS] and analyzing was performed by T-test, Wilcoxon and Mann-Whitney test. Findings showed that occupational therapy activities decrease the mean of significant differences of negative symptoms of schizophrenia such as flat affect, mutism, apathy, dissocial, loss of attention and the mean of significant difference in two groups, revealed a significant statistics difference in both at the beginning and the end of this study. Because occupational therapy and its related activities has an effective role on the symptoms of schizophrenia patients, rehabilitation is suggested in different field of treatment so that patients can get appropriate self respect and as well as a good level of social interactions.

[Prevalance of Childhood Brain Tumors at Mophid Hospital in Tehran [1996-2002]]

Central nervous system tumors are the most common soild tumors in children, which are very important because of nonspecific clinical manifestation, delayed diagnosis, complication and relatively high mortality. The aim of this study from different angles and different aspects is to arrive at workable solutions towards appropriate management of these cases. An "existing data" study was carried out by using data of 120 patients [age<14 years] with brain tumors operated in Mophid hospital during 8 years [1996-2002]. Variables included age, gender, tumor site, pathology of tumor, symptoms, signs, time period of first clinical manifestation till the definite diagnosis. Results showed that female to male ratio was 3: 2. The most common tumor was astrocytoma [50%]. The most frequent location of tumor was posterior fossa [52%]. The major peak in the incidence of tumors was observed between 5 and 9 years. The longest period between disease onset till final diagnosis was related to astrocytoma [180days]. vomiting [63%] and headache [56%] were the commonest complaints of patients referring to the hospital. DTR changes [39%] and cerebellar signs were reported as most common neurologic findings. Clinical findings of these tumors are usually nonspecific therefore physician should recognize the clinical presentations and put them in their differential diagnosis which would reduce time period of disease onset until final diagnosis and thus decrease mortality and morbidity due to this tumors. A comprehensive study is recommended in order to estimate survival, response to treatment and complications resulting from it

[Patients' satisfaction from medical and nursing services]

Introduction: Patients' satisfaction is a point, which has nowadays found its importance in medical Services. This can be a good scale to measure and evaluate medical services quality-reflexing patients' needs, expectation and wishes fulfillments. This study has tried to investigate the patients' satisfaction from medical and nursing service

Methods: This is a descriptive study of which the data were collected by questionnaires including three sections [demographic characteristics and satisfaction levels from medical and nursing services]. The subjects included 358 Patients' randomly selected, being discharged from hospital. Satisfaction levels were measured with Lickert scale in which the patients had been asked to determine their satisfaction from services by words as quite satisfied, somehow satisfied, dissatisfied, quite dissatisfied and indifferent

Results: The findings showed that most of the patients [68.7%] were satisfied with medical services while this value was 66.5% for nursing services. X[2] test was used to determine the association between demographic characteristics and satisfaction. The statistical results showed a significant association between sex, age, education degree, hospitalization history and satisfaction from medical nursing service

Discussion: On the whole, the findings showed that medical and nursing services have satisfied the subjects. The patients were more satisfied with specific wards, possibly either due to a lower life expectancy in these ward which decreases patients expectation or more precise care the doctors and nurses provide the patients with in these wards