kazem khosravi

P roof of retaliation (qi.sas) in premeditated murder requires conditions, one of which is the equivalence of the perpetrator and the victim in “religion”. This condition is due to the controversy of Islamic jurists that there are three sects of narrations in relation to it. Thus, the Shiite jurists, by rejecting the narrations based on the retaliation of the Muslim killer against the Dhimmi infidel (first category), have been believed in the non-retaliation of the Muslim killer  murder of a muslim murderer against the tributary (dhimmi) infidel (third category). These narrations by attributing narrations tending to corroborate retaliation in the case of habitual murder, they refer to the absoluteness of some verses of the Holy Quran, such as the verse of denying (no) domination (Allah will by no means give the unbelievers a way against the believers), as well as the consensus of the jurists. However, it seems that their reasons for not proving (ascertaining) the retaliation of a Muslim murderer, absolutely or non- habitually, face serious problems. So that by renouncing the mentioned narrations to the infidel deserving to be fought with, finally in the face of the intentional killing (deliberate killing) of a Muslim against a dhimmi infidel (Tributary infidel), there will be no choice but to prove (ascertain) retribution.

Sometimes he commit all crimes, but he does not achieve the result again. If this failure to fail to achieve the result is due to a lack of subject matter or a failure to act as a means of committing a crime, it would be impossible to commit a crime. Regarding the method of this research, which is fundamental (descriptive-analytic), by referring to the principled books, we find that the Shichr('39')a principals in their writings discussed the topic of discontinuance in its own literature and literature. It seemed to me that discourse was deliberately dealt with in the formulation of a procedural principle , Expressing the possibility of the occurrence of a result outside the field, which can undoubtedly only be compatible with the crime.However, the legislator, in the wording of article 122 of the Islamic Penal Code, regards the punishment of perpetrators of a crime as imposing a distinction between legal and material grounds. This separation of legislatures seems consistent and consistent with the correct view of some of the principals such as Sheikh Ansari (RA) In connection with the absence of eagles and punishments

Ethanasi, translated into Farsi with terms such as sickness with pity, medical illness, accelerated death, mourning for mercy, death and sweet death, etc. In one of its examples, intentional deprivation of life from one Patient with severe illness is defined on his request. In the context of euthanasia, there has been a lot of moral debate that some of them regard as contrary to the high morals and dignity of humankind, and in contrast to others, they do not see it in the context of morality. In any case, regardless of ethical issues, it seems that the Iranian legislator, by virtue of Article 365 of the Islamic Penal Code approved in 1392, considers euthanasia as a coincidence with other killers who claim retaliation. Since it is voluntary in euthanasia or pious murder, the consent of the person to his murder on the other is the basis of the discussion, this phenomenon is more controversial among the jurists. Therefore, the jurists who consider the right of qisas first and foremost to be innocent against him consider his consent in the fall of the Qisas. In contrast to the jurists who consider the right of qisas first and foremost to the victim's heir, it is natural to regard the consent of the criminal against him before his death, and regard the killing of this person, even if he is satisfied, with retaliation for qisas. As we study the books of jurists and inquiring into the arguments of their supporters and opponents, we conclude that while distinguishing between the ruling and the state of affairs, the permission of the person to be murdered actually prevents the establishment of the right of retribution, so Who, despite this permission, will not have any right to retaliation against the returnee or his parents. Therefore, we do not find any evidence of the opponents of Euthanasia so powerful and fundamental that it could be relied upon as a retribution to Euthanasia. Therefore, it is desirable that our legislator, in the light of the rich jurisprudential support in this regard, and the necessity of a differential treatment of these people with other killers in the relevant laws, should be comprehensive, more specialized, and more efficient.

Comparative Evaluation of microleakage of Bulk-fill and Posterior Composite Resins Using the Incremental Technique and a Liner in Cl II Restorations Abstract
I recent years there has been a surge in the use of tooth-colored restorations. However, the polymerization shrinkage of these materials can form gaps, resulting in microleakage. This study aimed to compare microleakage by using different materials and techniques.
In this experimental study, Cl II cavities were prepared on the mesial surfaces of 60 sound human third molars. The teeth were randomly divided into five groups (n=12): Group 1 were filled with Surefil posterior composite using the oblique incremental technique. In group 2 Surefil SDR flowable composite was placed at the base of cavities followed by filling the cavity with Surefil posterior composite. Specimens in group 3 were restored only with Surefil SDR flowable composite resin in two steps, and in group 4, a layer of G-aenial Universal flow composite with 1 mm thickness was placed as the liner and the rest of the cavity filled with the Surefil posterior composite using the oblique incremental technique. Group5 benefited from snow plow technique using G-aenial Universal flow and Surefil posterior composite. Samples thermocycled and placed in 0.5% fuchsine solution for 24 hours. The teeth were evaluated under a stereomicroscope for the deepest dye penetration. Kruskal-Wallis and Mann-Whitney tests were used for analysis of data.
The highest frequencies of scores 1 and zero were recorded in the group 5 which indicating the least microleakage in this group.
G-aenial Universal Flo composite resin with the snow plow technique resulted in a significant decrease in the microleakage.

Despite the growing tendency toward tooth-colored restorations in dentistry, polymerization shrinkage and subsequent marginal microleakage remains a problem. The aim of this in vitro study was to compare microleakage between silorane-based and methacrylate-based composite resins at different time intervals and with different restorative techniques. In this in vitro study, 108 sound extracted human molar teeth were used. Mesial and distal proximal class II boxes with dimensions of 1.5 mm depth and 4 mm width were prepared. The gingival margins of all cavities were 1 mm below the cement enamel junction. The teeth were randomly divided into three groups based on test materials. In the fi rst group, the teeth were restored by a nanocomposite (Filtek Z350XT, 3MESPE) and SE Bond adhesive (Kuraray, Japan), in the second group, the teeth were restored with a silorane-based (Filtek P90, 3MESPE) and Filtek P90 Adhesive (3M ESPE, USA) and in the third group, the teeth were restored with a microhybrid posterior composite resin (Filtek P60, 3MESPE) and SE Bond adhesive (Kuraray, Japan). Half of the proximal cavities in each of these three groups were restored in two horizontal layers and the other half in four horizontal layers. After a period of aging (24-h, 3-month and 6-month) in water and then application of 500 thermal cycles, the teeth were immersed for 24-h in 0.5% fuchsin and evaluated under a stereomicroscope at ×36 magnifi cation to evaluate leakage in gingival margin. Data was statistically analyzed using Kruskal-Wallis and Mann-Whitney U-tests. P ≤ 0.05 was considered as signifi cant. In Z350XT statistically signifi cant differences were observed in microleakage in comparison of 24-h and 6-month intervals (P = 0.01) that was higher in 6-month. Comparison of microleakage in P90 and P60 composite resins was also statistically signifi cant and was less in P90. Microleakage was not signifi cantly different between P90 and Z350XT at 24-h. However, this difference was signifi cant at 3-month and 6-month intervals. Differences in microleakage of P60 and Z-350XT composite resins were not statistically signifi cant in all intervals (P = 0.38). P90 showed the lowest microleakage during storage in water. Z350XT had microleakage similar to P90 within 24-h, but after 6-month of storage in water, it showed the highest microleakage among all the groups. The number of layers (2 layers vs. 4 layers) did not result in any differences in microleakage scores of the composite resins (P = 0.42). Water storage times did not result in any signifi cant effect on microleakage of P90 and P60.

Dental composite resins، as the name implies، are composite materials composed of organic and inorganic elements. The main components of dental composites are polymers، organic and inorganic filers، an initiator and an activator. In addition، some elements، referred to as silanes، are added to the surface of non-organic phases or fillers of composite resins for a stable bond between the two organic and inorganic phases. The aim of this study was to review the chemical structure of dental composites with a special emphasis on nano-composites and new composites. Review Report: This review was carried out by running a search in various databases including Pubmed and ISI Web of Science from 1987 to 2010 using the key words dental composites، nano-composite and chemical structure. In the recent decade، major changes have taken place in the chemical structure of dental composites; these changes include fluoride- and calcium phosphate-releasing nano-composites and use of nano-molecular processes to construct tooth enamel by using nano-rods، nano-spheres and amelogenin. With a proper knowledge of changes in the chemical structure of dental composites، clinical behavior of these materials can be evaluated more properly. It appears that new changes are going to have important effects on the clinical behavior of newly introduced composites; however، further research is required in this respect.

Dental adhesives are widely used in modern dentistry to provide retention of composite resin restoration and to reduce associated marginal microleakage. We aimed to evaluate the effect of adding silica fillers to adhesive on microleakage of composite restorations in different times. Forty-eight premolars were collected in 0.5% chloramine T solution. The teeth were divided into two groups. CLV cavities were prepared. In the first group, SE bond and in the second group, experimental unfilled SE bond were applied. In subgroups 1 of both groups, the teeth were incubated for 3 months then evaluated. In subgroups 2 of both groups, evaluation was performed after 24 hours. Cavities were filled with Z250 composite resin. Before incubation, samples were thermocycled at 5 to 55° C in 1000 cycles, then immersed in silver nitrate solution and afterwards developer solution for microleakage evaluation. They were then mounted, sectioned and observed under steriomicroscope and scanning electron microscope for scoring. The data were analyzed with Kruskal-Wallis and Mann-Whitney tests. There was significant difference in microleakage between groups in different times. There was no significant difference between occlusal microleakage regardless of time (p<0.001). The difference between cervical microleakage of two adhesive types was not significant (p=0.533). There was significant difference between 24 hours and 3 months storage (p<0.001). No significant difference was detected between filled and unfilled adhesives regardless of time (p<0.001). Although there was no significant difference between the two adhesives, unfilled adhesives performed slightly better than filled adhesives.

As the use of different irrigants to eliminate residual debris and smear layer inthe field of endodontic is unavoidable, by considering the effect of irrigants on the bond strength of resin composite restorations, this study was designed to evaluate the effect of a mixture of a tetracycline isomer, an acid, and a detergent (MTAD) on the shear bond strength of two self-etch adhesives, Clearfil SE Bond and Adper Prompt L- Pop to dentin. The crowns of 80 extracted premolars were transversally sectioned to expose dentin. Flat dentin surfaces were wet abraded with 320-grit abrasive paper and randomly assigned to eight groups according to two self-etch adhesive and four dentin surface treatments: direct application over smear layer (no treatment), etching with 35% phosphoric acid for 15s, 1 min 5.25% NaOCl/1 min MTAD and 20min 1.3% NaOCl/5min MTAD. Shear bond strength was tested 24 h after storage in distilled water at 37ºC in incubator. Data were analyzed using one-way ANOVA followed by duncan post-hoc (α=0.05). Phosphoric acid etching prior to SE Bond application significantly decreased the shear bond strength to dentin (P<0.05). Application of MTAD clinical protocol (20min 1.3% NaOCl/5min MTAD) did not significantly decrease the shear bond strength of self-etch adhesives to dentin (P=0.745) Based on the results of present investigation, it seems that the use of clinical protocol of 1.3% NaOCl as a root canal irrigant and a 5-min application of MTAD as a final rinse to remove the smear layer has no adverse effect on the shear bond strength of self-etch adhesives to dentin.

Surface microhardness is a physical property which access the effect of chemical and physical agents on hard tissues of teeth, and a useful way to examine the resistance of fluoride treated enamel against caries. The purpose of this study was to evaluate microhardness of enamel following pH-cycling through demineralization and remineralization using suspensions of dentifrices with different fluoride contents. In this in vitro study 56 enamel blocks of primary incisors were soaked in demineralizing solution and four dentifrices suspensions including: Crest 1100 ppm F (NaF), Crest 500 ppm F (NaF), Pooneh 500 ppm F (NaF,) and Pooneh without fluoride. The means and percentage changes of surface microhardness in pre-demineralization, after demineralization and remineralization stages in four groups were measured. The findings of four groups in three stages were compared by, ANOVA, Tukey and paired t-tests. (α=0.05) Average surface microhardness changes of Crest 1100 ppm F, was higher than Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride. The percentages of surface microhardness recovery for Crest 1100 ppm F, Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride were 45.4, 35.4, 28.6, and 23.7 respectively. Demineralization treatment decreased the surface microhardness of enamel (P<0.05) and the surface microhardness recovery in all groups were significant (P<0.0001). Surface microhardness of enamel after remineralization by Crest 1100 ppm F was higher than Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride.

In many cases, it is necessary to bond orthodontic attachments to composite resin restorations. The aim of this study was to evaluate the effect of different surface treatments and duration, aging and the adhesive type on shear bond strength of orthodontic brackets to composite resin surfaces. In this experimental study, 204 discs of two composite resins (Z100 and Point 4) were prepared and mounted in acrylic blocks. Half of the specimens in each group (52) were stored in distilled water at 37ºC for 3 months before bonding to evaluate the effect of aging. Each of the 4 groups were subdivided into 4 subgroups of 13 specimens each according to the surface treatment (application of diamond bur followed by phosphoric acid etching and phosphoric acid etching alone) and adhesive system used (self-curing and light-cured). Shear bond strengths were measured with Dartec testing machine after bracket bonding. Statistical analysis was carried out by four-way ANOVA (α=0.05). There were no statistically significant differences in mean shear bond strengths between the two restorative composite resins (p value = 0.529). Other variables under study (duration, surface treatment type and adhesive type) had statistically significant effects on the shear bond strength of orthodontic brackets to composite resin surfaces (p value < 0.05). Surface treatment, adhesive type and time elapsed after composite setting had significant effects on bond strength of orthodontic brackets to composite resin surfaces. Application of light-cured adhesives after surface roughening by bur and acid-etching can increase bond strength dramatically.

ntroduction: The low contents fluoride tooth pastes are effective and safe in pedodontics. The purpose of this in vitro experimental study was comparing microhardness changes following application of crest 1100 ppm, crest 500 ppm, pooneh 500 ppm and pooneh without fluoride. In this experimental invitro study fifty-six primary incisors were mounted in cylindrical tubes by epoxy resin. The initial surface microhardness of exposed surface was measured based on Vickers unit in 1500, 1000 and 500 micrometer by Buhler instrument. Then dental blocks were randomly divided into four groups as, Crest 1100 ppm, Crest 500 ppm, Pooneh 500 ppm and Pooneh without fluoride. The four groups were immersed in demineralization solution and tooth pastes suspension in PH-cycling Process. Surface microhardness of the samples was again measured after demineralization and suspension. Paired t-test, ANOVA and Tukey test were used for statistical analysis. The mean and standard deviation of initial surface microhardness was 341±29. The mean and standard deviation of surface microhardness after exposed suspensions of crest 1100 ppm, crest 500 ppm, pooneh 500 ppm and pooneh without fluoride were 258±5.6, 241±9.3, 248±7.6 and 238±7.9 respectively. The mean change in surface microhardness in crest 1100 ppm, crest 500 ppm, pooneh 500 ppm and pooneh without fluoride were 45.4, 28.6, 35.4 and 23.7 respectively. The mean change in surface microhardness between crest 500 ppm and Pooneh 500 ppm was not different. The difference in surface microhardness between crest 500 ppm, pooneh 500 ppm and pooneh without fluoride was insignificant.

One of the most important aspects of self-etching primer system in orthodontics is the duration of adhesive resin use after application of self-etching primer. Evaluating time delay effect on band strength is the objective of this study. In this interventional-axperimental study, premolar with sound buccal enamel were selected, and randomly divided in four groups, In the first group buccal surface were etched for 30 seconds, with 37% phosphoric acid. After washing and drying, primer XT was applied on teeth and brackets. Transbond XT was used in bonding. Light with 500 mw  was glowed from mesial, occlusal and distal surface for fifteen seconds, 5 and 10 minutes respectively. After thermocycling of all samples, debonding strength was measured with the help of DARTEC machine. Analysis was done by ANOVA and Duncan. The highest shear bond strength (19.4 Mpa) was seen in group one and the lowest (9.87 Mpa) in group four. Between the remaining groups and group one, there was a significant difference in mean shear bond strength. Scan electron microscope showed a strong deep tag between tooth enamel surface and adhesive in group one. Significant difference in shear bond strength of two groups, traditional etching and self-etching primer was observed. Mean of shear bond strength with self-etching primer method was acceptable and delay in applying resin composite had no significant effect on shear bond strength of brackets to enamel.

The dual cured resin cements are conventionally used for cementing indirect restorations, such as composite and ceramic inlays and onlays. The aim of this investigation was to evaluate the efficacy of two light-curing units, LED & QTH in polymerization of dual cured resin cement that were placed beneath the ceramic onlays. This experimental study was conducted using 20 specimens. Ten specimens were cured with QTH and the rest with LED light curing devises. Metal rings with 5mm in diameter and 0.5mm in thickness were placed next to the surface of the curved dentin of the molar teeth that were mounted in self cured acrylic resin. A Mylar strip was placed beneath the metal rings and they were filled with Maxcem dual cured resin cement; they were then covered with another Mylar strip. Next, the ceramic onlays with 2mm thickness were placed over the Mylar strips. The specimens were stored in a dry and dark incubator at 37◦C for 24 hours, after cemented onlays were cured for 60 seconds. The Vickers hardness was determined for each sample and data were analyzed by using student T-test and SPSS statistical software. The mean Vickers hardness for QTH cured specimens was 24.75(± 3.59), and this value was 33.92 (±2.28) for the LED light cured specimens. The mean group difference was statistically significant (P<0.001). Based on these findings, the efficacy of LED light curing unit was significantly more efficient in polymerization of resin cements that were placed underneath the ceramic onlays compared with QTH light-curing unit. Key words: Resin cement - Micro hardness test - Radiation effects - Light curing units. Corresponding Author: Dr. Feiz A., Department of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences. Isfahan, Iran.

When composite resin polymerizes, shrinkage stresses tend to produce gaps at the tooth restoration interfaces. The aim of this study was to assess the ability of two low viscosity resin systems (Single Bond, and Prompt L-Pop) and a specific surface penetrating (PermaSeal) sealant in preventing microleakage in class V composite restorations.
Hundred and five caries free human premolars were selected. Wedge shaped cavities with occlusal margins in enamel and cervical margins in dentin were prepared and restored using Single Bond and Z100 composite resin. After storing the samples in distilled water for 24 hours, finishing and polishing was done and then they were randomly divided into six groups each including 15 samples along with one control group. Other groups were sealed using three different agents with and without etched margins. The specimens were thermocycled and then, immersed in a 50% silver nitrate solution as tracer agent for 4 hours. All samples sectioned longitudinally and analyzed for leakage (dye penetration) using a stereomicroscope. Kruskal-Wallis and Mann Whitney U tests were used for statistical analysis.
Kruskal-Wallis test showed significant differences between the groups. Mann-Whitney U analysis revealed significant reduction in microleakage only in two groups namely, PermaSeal with etched and Prompt L-Pop without etched margins. There was no evidence of microleakage at the occlusal margins in any group.
The results obtained in this in vitro study showed that applying PermaSeal with etched and Prompt L-Pop without etched margins could reduce marginal leakage and improve marginal integrity.

Resin composites are common materials used to restore anterior teeth following root canal therapy, but are accompanied with shrinkage during polymerization. The aim of this in vitro study was to investigate the effect of the insertion method and polymerization shrinkage of resin composite on residual tooth structure.
Stereomicroscopy and computerized Finite Element Modelling (FEM) were used to compare residual stresses in endodontically treated, extracted maxillary central incisor teeth, in which the access cavities were restored with resin composite. Theoretical stresses derived from the FEM were analyzed during preparation and after teeth were restored using either a “bulk” or a “wedge incremental” method. These data were subsequently compared with stresses measured directly using strain gauges.
Results showed that intensive stresses, which had the potential to cause fracture in dental structures and composite de-bonding, were applied to teeth during polymerization.
According to the results of this study, the “bulk” build up led to less stress induction during restoration of teeth following root canal therapy.

The bond strength of restorative materials to dentin plays an important role in their clinical longevity. However since clinical trials are time consuming and costly and owing to rapid progressive in adhesive bonding systems, it’s essential to find a simple, rapid and standard method to evaluate the bond strength of bonding agents in laboratory tests. The purpose of this study is to evaluate the effect of different cross-head speeds on shear bond strength of two dentin bonding systems belong to fourth generation (Scotchbond Multi-Purpose) and fifth generation (Single Bond) and classify the failure modes (adhesive, cohesive or mixed). Methods & Materials: The buccal surfaces of 80 intact premolars were ground by a wheel shape diamond to the tip of the buccal cusps until the dentin is exposed. Then the buccal surfaces were flattened by paper discs with air and water spray. Finally, all samples were etched by 35% phosphoric acid. Afterwards the etched samples were divided into two 40 groups. Scotchbond Multi-Purpose was used for the first group and Single Bond for the second one. Then the Z100 composite was connected to the samples by 3×5 mm plastic molds. Each 40 group was divided by four 10 batches. Afterwards, the shear bond strength of each batch was determined by Dartec machine at four different cross-head speeds (0.5, 1, 2&5mm/min). After this step, the failure mode of the specimens was determined with stereomicroscope (56×). The quantitative variables were analysed with one way ANOVA and Duncan test and the qualitative variables were analysed with chi – square and fisher tests. Statistical analysis showed that in Scotchbond Multi-Purpose group there were no significant differences between mean shear bond strength and failure mode of the samples that were tested by cross-head speed of (0.5 & 1mm/min) & (2&5 mm/min), (P>0.05), but significant differences were observed (P<0.001) between batches that were tested by cross-head speed of (0.5 & 2 mm/min), (0.5 & 5 mm/min), (1&2 mm/min) & (1&5 mm/min). In the Single Bond groups there were no significant differences between mean shear bond strength and failure mode of various batches that were tested in difference cross-head speed (P>0.05). Evaluation of shear bond strength and failure mode of dentin bonding systems showed that they depend on the different cross-head speeds. However, the cross-head speed less than 1mm/min makes adhesive failures. Therefore it’s preferable for shear bond strength tests.