oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Search Results: 1 - 10 of 2021 matches for " Sh - Javadinejad "
All listed articles are free for downloading (OA Articles)
Page 1 /2021
Display every page Item
In vitro comparison of rotary instruments and K-files in root canal preparation of primary molars
Javadinejad Sh.,Zarejahromi M.,Mirenayat A.
Journal of Dental Medicine , 2008,
Abstract: "nBackground and Aim: The role of applying rotary instruments in reducing preparation time and proper root canal preparation have been approved in permanent teeth. The aim of this study was to compare the rotary instruments (Hero642) and K-files in root canal preparation of primary molars. Time and canal transportation were compared. "nMaterials and Methods: In this experimental, invitro study, 30 human extracted primary molars with 8 mm length were selected and divided into two equal groups. After preparing access cavity, group 1was prepared by K-files and group 2 by Hero642 systems. Before canal preparation, with # 15 K-file and after canal preparation, with master apical file, canal curvature was evaluated by Weine technique using Radiovisiography. Apical transportation was calculated. Time taken for preparation was recorded by chronometer. The results were analyzed with T-test and Mann-Whitney. P<0.05 was considered as the level of significance. "nResults: The average canal transportation angle was 3.42 for Hero642 group and 7.33 for K-file group (p<0.04). The mean instrumentation time was 4.28 for Hero642 group and 8.76 minutes for K-file group (p<0.001). There was a significant difference between two groups. "nConclusion: Based on the findings of this study, it is suggested to apply Hero642 rotary instrument for primary molar canal preparation due to less preparation time and less canal transposition.
Sealant Microleakage Evaluation of Three Common Fissure Preparation Methods
Javadinejad Sh.,Ghasemi Toodeshki D.,Salehi A.
Journal of Dentistry , 2011,
Abstract: Statement of Problem: In order to decrease microleakage, several preparation methods and cleaning techniques are used on the tooth surface before sealant application has been advocated. These techniques are pumice prophylaxis, fissure enameloplasty, adhesive, laser and air abrasion. Purpose: The purpose of this in vitro study was to evaluate microleakage of three different preparation techniques before acid etching and pit and fissure sealant application. Materials and Method: Sixty extracted sound third molars were randomly divided into 4 groups of 15 each. The teeth were prepared using 1 of the 3 occlusal surface treatments, 1) traditional pumice prophylaxis 2) fissure enameloplasty 3) air abrasion and acid etching. Then the sealant (Clinpro) was applied on the occlusal fissures of all the teeth based on the manufacturer's recommendations. The teeth were thermocycled between 5 and 55 degrees C for 500 cycles with a dwell time of 30 seconds and then stored in normal saline. All the teeth were sealed apically and coated within 1.5 mm of the sealant margin with two layers of nail varnish. They were then immersed in a 0.5% solution of fushin for 24 hours to allow dye penetration into the possible gaps between the enamel and sealant. Buccolingual cuts were made parallel to the long axis of the tooth. The surfaces were scored 0 to 2 for the extent of microleakage using a stereomicroscope. The results were analyzed through mann-Withney test and Mann-Whitney U test.Results: Pretreatment with air abrasion produced the lowest microleakage scores. In the control group, 46.7% microleakage was shown, in the pumice prophylaxis group 40% and in the enameloplasty group 53.3%. There was no significant difference in microleakage between the 3 fissure preparation methods prior to sealant placement ( p >0.05).Conclusion: Neither air abrasion nor enameloplasty followed by acid etching produced significantly less fissure sealant microleakage as compared to the traditional pumice prophylaxis technique.
Caries Prevalence in 12-year-old Children of Isfahan City Expressed by the Significant Caries Index
Sh - Javadinejad,M Karami,HR Azizi
Journal of Isfahan Dental School , 2006,
Abstract: Introduction: The Significant Caries (SiC) has been defined to determine dental caries for different societies by Word Health Organization. The good of present study was to evaluate Sic in 12-year-old students in city of Isfahan and make a comparison with dental caries risk factors.Methods and Materials: This was a descriptive cross sectional study. Three hundred and forty students, 12-year-old from Isfahan city were examined according to SiC Index by means of mirror and explorer. Risk factors and decay were evaluated recorded in separate check list. Findings were analyzed by Chi-square and SPSS soft ware.Results: The mean DMFT for all students were 2.4 and SiC Index was 4.6, which were directly related to factors such as regular brushing, parents’ educational level, mothers’ occupation families income, consump-tion of sweets, number of children in the family.Conclusion: SiC Index in 12-year-old students in Esfahan city was far from ideal SiC Index determined by World Health Organization which is 3. Therefore more attention to this group of student is recommended.
Nitric Oxide Concentrations in Saliva in Relation to Caries; Experience in 6-12 Years Old Children
SH Javadinejad,M Talebi,G Aslani
Journal of Isfahan Dental School , 2007,
Abstract: Introduction: Recently, there is a growing interest in the role of nitrate and nitrites in protecting against oral and gastrointestinal diseases. In human, ingested nitrate absorbs into the blood and concentrates in the salivary glands rapidly changes to nitrite. Nitrite may then be acidified through encounter with the plaque micro flora. The acidification of nitrite produces a mixture of nitrogen oxides as well as nitrous acid. Nitrous acid will spontaneously decompose to produce nitric oxide (NO). NO participates in the nonspecific defense mechanisms of the oral cavity to prevent bacteria from overgrowing. The aim of the study was to determine the correlation of nitric oxide with dental caries in children in mixed dentition period. Methods and Materials: The 3 ten-member groups of children aged 6 to 12 years with dfs < 1, 5 < dfs < 10 & dfs > 10 were selected. A 2 ml sample of saliva of each child were taken and transferred to laboratory, where by using the chromatograph unit, NO concentration was measured. Data were evaluated by ANOVA and t-tests. Results: Based on the laboratory findings, NO concentration in dfs < 1 group showed significant difference with other groups; but there was no significant difference of the NO concentration in groups with 5 < dfs < 10 and dfs > 10. Conclusion: The NO levels were higher in high dfs groups. NO production might be a host defense mechanism when dental caries increases. Key words: nitric oxide, saliva, caries
Comparative evaluation of microleakage of glass ionomer and resin based fissure sealants, using noninvasive and invasive techniques
SH Javadinejad,SM Razavi,S Dehghani
Journal of Isfahan Dental School , 2007,
Abstract: Introduction: Use of glass ionomer cement as pit and fissure sealant, has added benefit by its fluoride-releasing property. The efficacy of using invasive and non-invasive techniques was assessed by microleakage of Glass ionomer (Triage, G C Corporation, Tokyo, Japan) and Resin based sealants (Concise, 3M Dental Products, USA).Methods and Materials: In this in vitro experimental study, 80 sound premolars were divided into four groups of 20. In groups 1 and 2, Triage and in groups 3 and 4, Concise was used. In groups 1 and 3, fissures leaved intact (Noninvasive technique). In groups 2 and 4, fissures were prepared with tapered diamond bur (Invasive technique).The teeth were thermocycled at 5o-55oc for 250 cycles and immersed in 5% methylene blue solution for 24 hours. Sectioned samples were observed for the extent of dye penetration, and scores were based on established scoring criteria. 0- Without dye penetration.1- Dye penetration restricted to the outer half of the sealant.2- Dye penetration restricted to the inner half of the sealant.3- Dye penetration into the underlying fissure. The data were analyzed using Kruskall-Wallis and Man-Whitney tests.Results: There were no statistically significant differences between invasive and noninvasive techniques; but microleakage of Triage was statistically more than Concise.Conclusion: Because there was no difference between the two techniques, invasive technique is not recommended. Considering the recent controversies, it can be said that Triage cannot be a viable alternative for resin based sealants.Key words: Fissure sealant, Microleakage, Glass ionomer, Resin based, Noninvasive technique, Invasive technique
The Conductivity of Indium Phosphide Irradiated by Fast Electrons  [PDF]
Sh. Sh. Rashidova
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.411183
Abstract:

In this work, studied electrical conductivity(s) and annealing of radiation defects in crystals of n-InP are irradiated by electrons energy of 6 MeV and doses of 1017 el/cm2 (centimeter) and 2 × 1017 el/cm2 (centimeter). It is shown that alongside point defects (in the form of complexes with impurity atoms in crystals of n-InP) also form the complex defects of the type of disordered areas, annealing of which proceeds at T > 300°C that binds accumulating radiation defects.

Comparison of infiltration and inferior alveolar block anesthesia techniques in controlling pulpotomy pain in the primary mandibular first molars
Davood Ghasemi Todeshkechoi,Adeleh Pooyafard,Shahrzad javadinejad
Journal of Isfahan Dental School , 2011,
Abstract: Introduction: Pain control is of utmost importance in all dentistry fields. Anesthetic injection is perhaps the most difficult part of treatment in children. The most common anesthesia technique in the mandible is the inferior alveolar nerve block. As the block injection has a lasting anesthetic effect in children and also might cause traumatic injuries to soft tissues a different injection technique is needed. This study compared infiltration and block techniques for pain control during pulpotomy in the primary first mandibular molars.Materials and Methods: In this clinical study forty 5-8 year-old children were chosen. The subjects needed bilateral pulpotomy of primary mandibular first molars. This study was conducted based on a cross-over design. The patients were randomly divided into two groups. The patients in group A received an infiltration injection on the right side and a block injection on the left during the first and second sessions, respectively. The patients in group B received a block injection on the right side and an infiltration injection on the left during the first and second sessions, respectively. The patient pain was recorded at the moment of injection and on pulp exposure based on SEM (Sound Eye Molar) scale. Data was analyzed by Mann-Whitney U and Wilcoxon signed-rank tests. Statistical significance was defined at α = 0.05.Results: The results showed that at the moment of injection the SEM in the infiltration technique was significantly lower than that in the block technique, which demonstrates that the child can better tolerate the pain in the infiltration injection (p value < 0.001). However, the two techniques did not show significant differences in pulpal anesthesia based on the SEM scale.Conclusion: It seems the infiltration technique is superior to the block technique in controlling pain during pulpotomy in the mandibular primary first molars in 5-8 year-old children. Key words: Inferior alveolar nerve block, Infiltration anesthesia, Pulpotomy, SEM Scale, Pain control.
Accuracy of Cameriere method in chronological age estimation
Shahrzad Javadinejad,Mozhdeh Mehdizadeh,Reihaneh Torabi
Journal of Isfahan Dental School , 2012,
Abstract: Introduction: Various dental age estimation methods have been used, based on tooth development. In Cameriere method the distance of the apices of seven left permanent mandibular teeth is measured. The aim of this study was to compare dental age means estimated by Cameriere method and the means of chronological age. Materials and Methods: In this cross-sectional descriptive study, 109 panoramic radiographs of 67 females and 42 males aged 5 15 years were assessed. The variables included the number of teeth with full development and closed apices, the distance between the inner sides of open apices in immature teeth, and the tooth lengths. To accommodate the effect of magnification and x-ray angulation, the measurements were normalized by dividing them by tooth lengths. Finally, the normalized measurements of open apices, the sum of the normalized open apices, the number of teeth with closed apices, gender and chronological age were recorded using SPSS 18 for age estimation formula. Data were analyzed by Pearson’s correlation coefficient and independent t-test (α = 0.05). Results: Pearson’s correlation coefficient showed significant and inverse correlations between age and all the other variables. Differences between dental and chronological ages varied from -2.66 to 2.79 years. The median of chronological age was 10.67 and that of Cameriere age was 11.12 years. The difference between chronological age and estimated age was not significant (p value = 0.95). The differences between chronological and Cameriere ages were 0.73 in girls and 0.99 in boys. Estimated age was more accurate in girls (p value = 0.04). Conclusion: The present study indicated that Cameriere method was reliable for age estimation in our sample; also this method of age estimation was more accurate for girls than for boys. Key words: Age factor, Forensic dentistry, Panoramic radiograph, Tooth apex.
Clinical comparison of a self-etching fissure sealant with a conventional sealant: A 12-month follow-up
Shahrzad Javadinejad,Parvin Mirzakoucheki Borojeni,Morteza Saleki,Fatemeh Hajizadeh
Journal of Isfahan Dental School , 2012,
Abstract: Introduction: Self-etching fissure sealants have been introduced recently, leading to elimination of etching and rinsing, reducing working time and consequently increasing child cooperation. This clinical study was conducted to compare the retention rate, caries occurrence and marginal integrity of a self-etching fissure sealant (Prevent Seal) with a conventional sealant (Concise) over a12-month period. Materials and methods: In this clinical trial 192 first permanent molars of 48 children aged 7-9 years were selected. Self-etching sealants were randomly used for first permanent molars on one side of the mandible and contralateral side of the maxilla and conventional sealants (etch-and-rinse) were placed on the remaining first permanent molars. Clinical evaluation was performed at 3-, 6-, and 12-month intervals by a single blind examiner. The retention was classified as complete retention, partial loss and total loss. Caries incidence was assessed. Marginal integrity of sealants was also evaluated with modified U.S. Public Health Service (USPHS) codes. Data were analyzed with Friedman’s, Wilcoxon’s signed rank and McNemar’s tests using SPSS statistical software (α=0.05).Results: At the end of 12 months Concise had higher retention rates (87.5%) than Prevent Seal (12.5%), with statistically significant differences (p value < 0.001). Regarding marginal integrity of the sealants, Concise yielded significantly better results than Prevent Seal at all the follow-up examinations (p value < 0.001). However, there were no significant differences in caries incidence between the two groups (p value = 0.99).Conclusion: The results indicated that retention rate and marginal integrity of self-etching sealants are less than those of conventional ones at 12-month evaluation period. Key words: Clinical trial, Pit and fissure sealants, Tooth marginal integrity.
Phenomenological and Semi-microscopic Analysis for the Elastic Scattering of Protons from 12C Nuclei at Different Energies  [PDF]
Sh. Hamada, N. Amangeldi
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.45B013
Abstract:

Analysis of the elastic scattering of protons from 12C nuclei had been performed within the framework of both the optical model and single folding model at different proton energies; 17, 30.3, 40, 49.48 and 61.4 MeV. We have obtained the global potential parameters which could fairly reproduce the experimental data for p+12C elastic scattering at the aforementioned energies. The radial and energy dependence of the real and imaginary parts of the potential were calculated. Good agreement between experimental data and theoretical predictions in the whole angular range was obtained using both phenomenological approach (Optical Model), and semi-microscopic approach (Single Folding). In single folding calculations, the real part of the potential was calculated from a more fundamental basis by the folding method in which the NN interaction VNN(r), is folded into the density of the target nuclei and supplemented with a phenomenological imaginary potential. The obtained normalization factor Nr is in the range of 0.75 - 0.9.

Page 1 /2021
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.