فهرست مطالب farzaneh afkhami

La présente étude a permis de réaliser l’évaluation des métaphores traduites de Divan de Hâfez proposées par De Fouchécour afin d’avoir une vision générale sur la manière d’emploi de la métaphore dans les deux langues française et persane. Nous avons profité des parties les plus importantes et les plus utiles des idées de Meschonnic dans ses différents ouvrages, pour vérifier la manière d’agir de métaphore, son effet sur le sens et nous avons l’intention de vérifier les points communs et les points différents d’emploi de la métaphore dans les deux langues française et persane. Le principe de base c’est que le travail du traducteur doit avoir la même qualité que celui de l'auteur. Pour cela, l'objectif de ce travail de recherche est de trouver les stratégies possibles pour traduire les figures du sens et aussi on va constater des solutions trouvées par De Fouchécour pour en relever des moyens dans la voie de la traduction des figures de sens. Le travail proposé est articulé autour de trois parties: la première présente quelques principes des idées d’Henri Meschonnic, la seconde consiste en des remarques sur les figures du sens en français et en persan et la troisième présente l’analyse des ghazals.

The combination of mineral trioxide aggregate (MTA) and 2% chlorhexidine (CHX) has been recently introduced as an intracanal medicament. The aim of this study was to evaluate the potential cytotoxic effects of MTA mixed with 2% chlorhexidine gel on human periodontal ligament stem cells (PDLSCs) and compare it with other common endodontic regeneration medicaments.

Minimum inhibitory concentration and minimum bactericidal concentration of six experimental groups against Enterococcus faecalis was determined. The study groups consisted of RetoMTA mixed with 2% chlorhexidine gel (MTA+CHX), calcium hydroxide (CH), CH mixed with CHX gel, two concentrations of double antibiotic paste, and 2% CHX. The direct cytotoxic effect of minimum bactericidal concentration was evaluated by MTT on PDLSCs on days 1, 3, and 7. One-way ANOVA and post hoc tests were used for data analysis (P<0.05).

The viability of cells treated with MTA+CHX decreased significantly over time (P<0.05) making this group the most cytotoxic intracanal medicament on the 3rd and 7th days of treatment. On day one, the highest viability percentage was detected in the CH+CHX group followed by the CHX group. On day 3, CH+CHX and CHX groups displayed the highest viability percentage. On day 7, the highest viability was observed in the CHX group, which showed no significant difference with the control group (P=0.12).

Regarding the antimicrobial potency of intracanal medicaments at minimum bactericidal concentration levels, CHX gel appears to be the least cytotoxic drug, while MTA+CHX shows the highest reduction in viability percentage

This is particularly apparent within the insects that show high variations in genitalic form between closely related species. Static allometry is one of the effective approaches for quantification of such variation. Despite the crucial roles of the parasitic Hymenoptera in the ecosystems, little is known about the sexual selection in this order, compared with other insect orders. We examined the allometry of different morphological traits in 35 males and 35 females of Habrobracon hebetor (Say, 1836) (Hymenoptera: Braconidae) from a laboratory colony reared in Mashhad city, for the first time. The aim was the investigation of allometric relationships of different body traits as a way for quantification of the natural selection impacts on the different body parts. 12 genitalic and non-genitalic body parts of H. hebetor males and females were photographed and measured. Principal Component Analysis (PCA) was used to explore the variance of the traits and two regression analysis methods to obtain the allometric slopes. All the non-genitalic traits in male and female wasps showed isometry except pterostigma width in male wasps which showed positive allometry. In male genitalia, two traits showed strong negative allometry and one trait showed isometry. Our findings showed that in this species males with an average size of genitalia were more successful in generating viable offspring than males with relatively smaller or larger genitalia sizes and this is irrespective of the overall body size. Our results showed for the first time that such stabilizing sexual selection might operate on genital size in the braconid wasps.

 Our study aimed to assess the diagnostic accuracy of different voxel sizes for cone-beam computed tomography (CBCT) when detecting strip perforations of variable sizes. We used 0.2 and 0.3 mm3 voxel for detecting root strip perforations. 

This was an in vitro study conducted on 155 extracted humans' mandibular first molars. The teeth were randomly divided into five groups (n=31). Perforation were not induced in the control group. In the remaining four groups, strip perforations of 0.5, 1, 1.5, and 2 mm diameters were created in the mesiolingual canal using #3 Gates Glidden drills. The CBCT scans were taken first with a 12×9 cm field of view (FOV), 90 kVp, 4 mA, and 0.2 mm3 voxel size for 24 sec and then with a 12×9 cm FOV, 90 kVp, 2 mA, and 0.3 mm3 voxel size for another 24 sec. Two observers evaluated the images and reported the largest diameter of perforations. The results were compared with the gold standard values (determined by an electronic digital caliper) using statistical methods, including the kappa coefficient and generalized estimating equation (P<0.05). 

 Based on the findings of our study, the inter-observer agreement ranged from 58-100%, while the intra-observer agreement was reported to be around 100%. The difference in accuracy between 0.2 and 0.3 mm3 voxel sizes was not statistically significant (P>0.05). In addition, the accuracy of detecting different perforation sizes in the CBCT did not follow a specific pattern. 

 This in vitro study showed that CBCT is a reliable diagnostic tool, and even in lower dosages of 0.3 mm3 voxel size, image resolution and diagnostic accuracy was not affected. Moreover, smaller root perforations could be detected as accurately as larger ones with CBCT.

The aim of the present study is to compare the effect of SmearClear and sodiumhypochlorite (NaOCl), chlorhexidine (CHX) and normal saline (NS) on the push-out bond strength of Resilon/Epiphany system to dentine. Methods and Materials: In this in vitro study; 48 single-rooted teeth were selected and decoronated from the CEJ. Then the specimens were divided into four groups (n=12). The roots were prepared by single length technique using MTwo rotary system. The final irrigations of the canals were done using 2% CHX, normal saline, 5.25% NaOCl or SmearClear. The canals were obturated by Resilon/Epiphany system. The teeth were cut perpendicular to their longitudinal axis and four 1-mm-thick sections were obtained from coronal and mid root regions. The push-out bond strength of Resilon/Epiphany system to dentin were calculated and bond failure patterns were assessed. The data were subjected to two-way analysis of variance and Tukey’s tests. The highest bond strength values were reported for SmearClear and the lowest values for the NS solutions. The effects of irrigant type (P<0.05) and canal area (P<0.0001) on the bond strength of Resilon to dentin were significant (P<0.05). Higher bond strength values were obtained in the mid root areas compared to the coronal regions. In two-by-two comparisons, significant differences in bond strength were found between SmearClear and normal saline (P<0.05) while the other irrigants showed no significant differences (P>0.05). SmearClear solution was able to increase the push-out bond strength of Resilon to the dentin similar to other irrigants (NaOCl and CHX). Therefore, it can be used for the root canal irrigation and smear layer removal in the clinical situations.

Vertical root fracture inevitably leads to tooth extraction. Thus, root filling with obturating materials and sealers that can reinforce the tooth would be an ideal way to reduce fracture in root treated teeth. This study aimed to assess the fracture resistance of roots following the application of different sealers including Epiphany, iRoot sealer and AH-plus.
Methods and Materials: Fifty extracted human single-canal premolars without caries, curvature or cracks were used in this study. Tooth crowns were cut to yield 13-mm-long roots. Five roots were put in the negative control group and were left unprepared. Forty-five canals were prepared using ProTaper rotary files up to F3 and were then randomly divided into three groups based on the sealer type (n=15). The root canals were filled using cold lateral condensation technique with gutta-percha and AH-Plus sealer, gutta-percha and iRoot sealer and Resilon and Epiphany sealer, in groups one to three, respectively. The roots were then mounted in acrylic molds for fracture resistance testing and subjected to compressive load at a crosshead speed of 1mm/min until fracture. Data were analyzed using the one-way ANOVA.
The mean fracture resistance was 673.38±170.42 N in AH-Plus, 562.00±184.68 N in iRoot, 708.03±228.05 N in Resilon and 592.59±117.29 N in the control group. No statistically significant difference was found between the experimental groups and the negative control group (P=0.26).
Application of AH-Plus, bioceramic and Resilon sealers did not change the fracture resistance of roots compared to that of unprepared root canals.

The aim of this study was to compare the antibacterial effect of Persian green tea extract (GTE) and 2.5% sodium hypochlorite (NaOCl) against Enterococcus faecalis (E. faecalis) as an intracanal irrigant.
Methods and Materials: Thirty freshly extracted teeth were instrumented and sectioned into mesial and distal segments. The specimens were put into wells containing 2 mL of E. faecalis-containing medium. After 3 weeks, the specimens were removed and divided randomly into three groups (n=20). Each group was exposed to 3 mL of different irrigants for 3 min. Groups 1, 2 and 3 were irrigated with GTE, 2.5% NaOCl and normal saline, respectively. Biofilm formed in the middle third of the root canal was carved by sterile scalpel and cultured in Mueller-Hinton medium. Number of colony forming units (CFU) was counted on each plate. In addition, antimicrobial activity of the irrigants was evaluated by the agar disc diffusion test. The diameter of inhibition zone (IZ) around each irrigant was evaluated. The Kruskal-Wallis and Dunn tests were used to analysis the data.
While in NaOCl group no bacterial colonies were observed, the mean number of E. faecalis in GTE and control groups were 275±74 CFU/mL (P This research highlighted the potential role of plant extracts in antimicrobial root canal irrigation protocol.

The aim of the present in vitro study was to evaluate the disinfection ability of 980-nm diode laser in comparison with sodium hypochlorite (NaOCl) as a common root canal irrigant in canals infected with Enterococcus faecalis (E. faecalis). Methods and Materials: The root canals of 18 extracted single-rooted premolars were prepared by rotary system. After decoronation, the roots were autoclaved. One specimen was chosen for the negative control, and the remaining teeth were incubated with E. faecalis suspension for two weeks. Subsequently, one specimen was selected as the positive control and the remaining samples were divided into two groups (n=8). The samples of the first group were irrigated with 5.25% NaOCl and the second group were treated with a 980-nm diode laser. Microbial samples were taken from the root canals and bacterial cultivation was carried out. The average value and the standard deviation of colony-forming units (CFU) of each specimen were measured using descriptive statistics. The student’s t-test was used to compare the reduction in CFU in each group. The equality of variance of CFU was measured by the Levene’s test. NaOCl resulted in 99.87% removal of the bacteria and showed significantly more antibacterial effect compared to the 980-nm diode laser which led to 96.56% bacterial reduction (P<0.05). Although 5.25% NaOCl seems to reduce E. faecalis more effectively, the diode laser also reduced the bacterial count. Therefore a 980-nm diode laser could be considered as a complementary disinfection method in root canal treatment.

This study aimed to assess and compare the apical sealing ability of HEROfill® Soft-Core system and lateral condensation technique in fine curved canals using the fluid filtration method.
Forty human mesiobuccal root canals of mandibular first molars with 25° to 40° curvatures were instrumented to an apical size 30/0.04. Roots were randomly assigned to two experimental groups of 15, designated as groups A and B. Two control groups, each containing five teeth, served as positive and negative controls. Group A was obturated using lateral condensation technique and group B with the HEROfill® Soft-Core system. The groups were tested for microleakage using an in vitro fluid filtration apparatus with 0.5 atm pressure at zero, two, four, six, eight and 10 minutes. Independent t-test was used to analyze the microleakage data.
The mean and standard deviation (SD) values for fluid microleakage in the lateral condensation group were 0.58±0.49 µL/min, 0.68±0.35 µL/min, 0.74±0.22 µL/min, 0.71±0.29 µL/min and 0.60± 0.29 µL/min at two, four, six, eight and 10 minutes, respectively. The mean and SD values for fluid microleakage in the HEROfill® group were 0.53±0.42 µL/min, 0.67±0.34 µL/min, 0.69±0.26 µL/min, 0.73±0.33 µL/min and 0.63±0.26 µL/min at two, four, six, eight and 10 minutes, respectively. The difference between the lateral condensation and HEROfill® groups was not statistically significant at two (P=0.776), four (P=0.909), six (P=0.562), eight (P=0.861) or 10 (P=0.765) minutes.
The HEROfill® system and cold lateral condensation technique were equally effective for apical sealing of curved canals.

Pulpectomy is the preferred treatment for restorable primary teeth with symptomatic irreversible pulpitis or periradicular lesion. Considering the rather new application of rotary files for pulpectomy of primary teeth, the aim of this study was to compare the cleaning efficacy and instrumentation time of hand K-files and Mtwo rotary system for preparation of human primary molars. Methods and Materials: This experimental study was conducted on 100 extracted primary maxillary and mandibular intact molars with no resorption. Access cavities were prepared and India ink was injected into the root canal on a vibrator using an insulin syringe. Canals were then divided into 5 groups (n=20): in group I, canals were instrumented using K-files up to #25 for mesial and buccal canals and #30 for palatal and distal canals. In group II, canals were prepared using Mtwo rotary files (15/0.05, 20/0.06 and 25/0.06 for mesial and buccal canals and 15/0.05, 20/0.06, 25/0.06 and finally 30/0.05 for distal and palatal canals). In group III, root canals were only irrigated with saline. Groups IV and V were the positive and negative control groups, respectively. The time required for cleaning and preparation of the canals for each of the specimens in groups I, II and III was recorded. The mean score of cleanliness of Mtwo was not significantly different from K-file group (P>0.05). However the mean instrumentation time in Mtwo group was significantly shorter (P<0.001). Although there were no differences regarding the cleaning efficacy of either system, Mtwo rotary files were far more time efficient.

Mineral trioxide aggregate and calcium hydroxide are considered the gold standard pulp-capping materials. Recently, Portland cement has been introduced with properties similar to those of mineral trioxide aggregate. Histopathological effects of direct pulp capping using mineral trioxide aggregate and Portland cements on dog dental pulp tissue were evaluated in the present study. This histopatological study was carried out on 64 dog premolars. First, the pulp was exposed with a sterile bur. Then, the exposed pulp was capped with white or gray mineral trioxide aggregates and white or gray Port-land cements in each quadrant and sealed with glass-ionomer. The specimens were evaluated under a light microscope after 6 months. Statistical analysis was carried out using Kruskal-Wallis test. Statistical significance was defined at α=5%. There was no acute inflammation in any of the specimens. Chronic inflammation in white and gray mineral triox-ide aggregates and white and gray Portland cements was reported to be 45.5%, 27.3%, 57.1% and 34.1%, respectively. Al-though the differences were not statistically significant, severe inflammation was observed mostly adjacent to white mineral trioxide aggregate. The largest extent of increased vascularization (45%) and the least increase in fibrous tissue were ob-served adjacent to white mineral trioxide aggregate, with no significant differences. In addition, the least calcified tissue formed adjacent to white mineral trioxide aggregate, although the difference was not significant. The materials used in this study were equally effective as pulp protection materials following direct pulp cap-ping in dog teeth.

Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography. Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured. Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm. The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions.

Root canal treatment is based on elimination of intraradicular microorganisms. Calcium hydroxide Ca(OH)2 is the most widely used material for canal dressing, However, Enterococcus faecalis has been reported to be resistant bacteria in persistent apical periodontitis. The purpose of this study was to evaluate the efficacy of Ca(OH)2 on the elimination of intraluminal and intratubular E. faecalis. 36 human unirooted teeth contaminated with E. faecalis. 30 Specimens in experimental group which were treated with 10% Ca(OH)2, or sterile water as a positive control (n=6). Specimens from each experimentagroup were randomly divided into 2 equal subgroups: A (n=15) had specimens incubated and sampled at 1 day; and B (n=15) had specimens incubated and sampled at 7 days. For each group, paper points were used to obtain the intraluminal E. faecalis and Gates Glidden burs to obtain intratubular bacteria either after one day or one week. Samples obtained from these root canal preparations were analyzed for bacterial load by counting the number of colony forming units (CFUs). A significant decrease in the number of CFUs was observed after dressing with Ca(OH)2 after 1 week camper to 1 day either in sampling with paper point or Gates Glidden. Additionally, no differences were observed between the antimicrobial properties of Ca(OH)2 on intraluminal and intratubular E. faecalis. significantly higher antimicrobial efficacy are measured by the number of CFUs after Ca(OH)2 medication after 1 week. Ca(OH)2 showed the same antimicrobial efficacy on intraluminal and intratubular E. faecalis.

Blood contamination of the canal during preparation can be a major problem in endodontics; this may result in apical microleakage. The aim of this in vitro study was to evaluate the effect of blood on apical microleakage of a resin-based root canal sealer (AH26) and a polymer-based root canal sealer (Epiphany). In this experimental study, 50 decoronated central incisors and canine teeth were prepared by RaCe rotary system and randomly divided into 4 groups (n=10). Groups A1 and A2 were obturated by Epiphany/Resilon and AH26/Gutta-percha, respectively. The obturations were performed with a single cone technique after drying root canals. In B1 and B2 groups, the test groups, 0.02cc citrated human blood was injected into dried root canals and they were obturated in the same manner. Ten specimens were served as positive and negative controls (n=5).The apical leakage was measured by means of a computerized fluid filtration method after 1 day and 3 weeks. The data was analyzed by One-Sample Kolmogorov-Smirnov, Independent Sample t-test and univariate analysis. Statistical significances were preset at α=0.05. There was no significant difference in apical microleakage of the two sealers after 1 day and 3 weeks in dry and blood environment (P>0.05). Sealer and environment had no interaction (P>0.05). Blood contamination has no significant effect on the apical microleakage of Epiphny and AH26.