roza haghgoo

The acidic component of liquid medicinal syrups used by pediatric patients may cause erosion and partial demineralization. This study aimed to evaluate the effect of cheese and casein phosphopeptide‑amorphous calcium phosphate (CPP‑ACP) on erosive lesions of primary teeth enamel following exposure to amoxicillin and ibuprofen syrups.

In this in vitro study, 60 noncarious deciduous molars were used. After measuring the surface microhardness of the samples, they were randomly separated into two groups and immersed in either amoxicillin or ibuprofen for 1 min three times per day. CPP‑ACP, cheese, and artificial saliva were then applied to each of the three subgroups (n = 10). After each immersion time, 10 min of therapy was given. Between treatment intervals, the samples were kept in artificial saliva. The microhardness was remeasured after 1 week. Data were analyzed using SPSS software through repeated‑measures ANOVA (α = 0.05).

All samples’ microhardness reduced considerably after immersion in liquid pharmaceuticals(amoxicillin [84.9 kgf/mm2 ] and ibuprofen [75.1 kgf/mm2 ]), but increased significantly following exposure to therapeutic solutions. There was no difference between the amoxicillin‑cheese and amoxicillin‑CPP‑ACP subgroups (P = 0.975). A statistically insignificant difference was found between the ibuprofen group and the ibuprofen‑CPP‑ACP subgroup (P = 0.499).

As a result, cheese and CPP‑ACP can be utilized to remineralize erosive lesions caused by amoxicillin or ibuprofen exposure.

The purpose of this in vitro study is to ascertain how NovaMin and Er,Cr:YSGG laser radiation affect the remineralization of primary tooth enamel lesions.

40 main teeth served as the study’s sample size. These teeth were allocated into five groups at random. The first group served as a negative control (artificial saliva); the second group served as a positive control (APF gel 1.23%); the third group NovaMin, the fourth group Er,Cr:YSGGlaser, the fifth group Er,Cr:YSGG laser and finally, the application of NovaMin. For the purpose of measuring microhardness, all samples were submitted to the dental materials laboratory three times.

The collected data were compared using the SPSS 28 program between the baseline measurement, after demineralization, and after remineralization. The data were analyzed using ANCOVA and Bonferroni tests. All groups demonstrated a considerable increase in microhardness as compared to the negative control group (P < 0.05). With the exception of the third and fourth groups, there was no discernible difference in the rise in microhardness between the other groups. The third and fourth groups were compared, and the results revealed that NovaMin had a greater impact than laser therapy alone (P = 0.023). Scanning electron microscopy (SEM) analysis backed up the findings.

In comparison to using the Er,Cr:YSGG laser alone, using NovaMin alone can speed up the remineralization of erosion lesions on the surface of primary teeth.

Mineral trioxide aggregate (MTA) is known as a common biomaterial for pulpotomy of primary molars, with limitation including high cost, difficult handling, and long setting time. This study was conducted to compare the clinical and radiographic success rate of Allium sativum oil and MTA in pulpotomy of primary molar teeth.

This randomized, controlled, clinical trial was performed on a group of children with at least two symptom‑free primary molars requiring pulpotomy. A total of 90 teeth were randomly assigned into two groups: After pulp amputation and hemostasis, Group I received MTA as medication in the pulp chamber and Group II received Allium sativum oil over the pulp stumps. Pulp chamber was then filled with reinforced ZOE paste (zinc oxide eugenol) and teeth were restored using stainless steel crowns. The follow‑up scheme of 6, 12, and 18 months was set, and teeth evaluation was conducted by a calibrated pediatric dentist based on the modified criteria proposed by Zurn and Seale. The results were analyzed using the generalized estimating equation analysis with the P = 0.05 as the level of significance.

The clinical success rate was 100% in both groups after all follow‑ups. The radiographic success rate was, however, 91.1% after 6.75. 6% after 12 and 18 months in Group II while it was 95.6% after 6, 91.1% after 12 and 18 months in Group I in those follow‑up points. The difference between the two groups was not statistically significant.

According to the results, Allium sativum oil has a high clinical and radiographic success rate comparable to those of MTA.

Promoting childrenchr('39')s oral health is the basis for increasing the level of community health and the goal of pediatric dentistry. By recognizing all the factors affecting the health and formation of the childchr('39')s health habits, a fundamental step can be taken to promote oral health. The aim of this study was to evaluate the effect of parenting styles and demographic characteristic on OHI-S (Simplified Oral Health Index) in 2018.

In this cross-sectional study, 244 children aged 6-12 years in Behbahan-Iran with their parents were studied. The demographic questionnaire (variables such as parents chr('39')age, economic status, gender, occupation and parentschr('39') education were recorded) and Bumrind questionnaire were used. The oral health status of children was assessed to determine the simplified oral hygiene index. Then, the obtained data were analyzed using SPSS 25 software and regression and Pearson correlation test.

 The results showed that the children of parents who used the permissive method had higher score of simplified oral hygiene index (P<0.001) and simplified calculus index (P<0.001). However, in children of parents who used the authoritative parenting style, a decreased simplified oral hygiene index (P<0.001) and simplified debris Index (P<0.001) were observed. However, the method of authoritarian parenting style did not have a significant relationship with the simplified oral hygiene index (P=0.890), simplified calculus index (P=0.404), and simplified debris Index (P=0.721).

Powerful authoritarin and authoritative parenting practices have a clear impact on the oral health status of children. Therefore, parenting paratices can be considered as one of the main factors affecting the oral health of children.

Dental caries is one of the most common chronic diseases around the world. Inhibitory effects of Magnolia Grandiflora bark extract has been proved on tooth decay both in vitro and by using free sugar chewing gum. This research aimed to examine the effect of Magnolia Grandiflora bark mouth-wash on the prevalence of Streptococcus mutans in dental plaque.

This crossover, placebo-controlled, clinical trial study, was performed on a total of twenty participants (aged 18 to 35 years) in both control and intervention groups and four phases. The prevalence of S. mutans was measured in a certain volume of volunteer’s dental plaque at the beginning of the project (phase 1), after the first prescription (phase 2), following the washout period (phase 3) and finally after the second prescription (phase 4) by culture on bacteriology medium. Plaque index and saliva sampling were carried out in follow-up visits by a dentist. The data were analyzed using T-Test (paired and independent) quantitatively.

There was a significant difference in S. mutans frequency in dental plaque between when the participants used Magnolia mouthwash and when they washed out or used a placebo (p<0.005). Results also showed a significant difference between Magnolia and Placebo groups in the mean count of saliva bacterial colony counts after oral administration in the first and second time (P<0.001 and P<0.004, respectively).

The current trial showed that Magnolia Grandiflora %0.3 mouthwash tends to decrease the number of S. mutans in dental plaque significantly. Therefore, its mass production and release to the oral health community are suggested. However, further studies with larger sample sizes and varying treatment are required to substantiate the findings of this study.

Most children get a lot of anxiety while they visit a dentist. The most important factor in the child's fear at the beginning of treatment is the syringe and needle. Ways to cope with this anxiety include behavioural control techniques such as mental regeneration, distraction, and induction. The purpose of this study was to compare the pain and anxiety in children when using a syringe and toy- shape syringe needle. This study was the first study that used a toy-shape needle cover.

This clinical trial study was conducted on 20 children age from 5 to 8 years. More than half of them were anxious with Cfss-Ds (Dental Subscale of the Children's Fear Survey Schedule) and FIS
(Facial Image Scale) anxiety diagnostic tests, and the rest of them were not anxious. Patients were randomly divided into two groups. The first group received local anesthesia with conventional syringe and the second group, by syringe with toy shape needle cover. Following, the first group received local anesthesia by syringe with toy shape needle cover, and the second group, by a conventional syringe. Heart rate measuring and pain evaluating test was performed. Analysis of heart rate and anxiety data was performed by non-parametric wilcoxonsianed Ranks T-test (P-value was considered significant at 0.001).

The mean amount of pain measured after using a syringe with a toy shape needle cover and using conventional syringe had a significant difference of 5.20% between the two groups. The pain was reduced in children who received local anesthesia by syringe with toy shape needle cover (P<0.001).

The physical appearance of the injection device plays an important role in reducing the anxiety and pain of injection in the children.

Direct pulp capping (DPC) is a conservative vital pulp therapy, which has some limitations in primary dentition. The aim of this study was to evaluate pulpal response of primary teeth after DPC with two biocompatible materials naming calcium-enriched mixture (CEM) and bioactive glass (BAG). Methods and Materials: This study was designed as a randomized clinical trial. After obtaining informed consent, 20 sound primary canines scheduled for orthodontic extraction, were selected. Following mechanical pulp exposure, the exposed site was capped with either CEM cement or BAG and then restored with amalgam. Teeth were extracted after two months and examined histopathologically. Parameters of hard tissue bridge (HTB) formation, its type and pulpal inflammation scores, were compared between the two groups. Data were analysed using the Fisher’s exact test. All CEM specimens showed inflammation scores of 0 (less than 10%). In the BAG group, inflammation scores of 0, 1 and 2 were observed in 7, 2 and 1 specimens, respectively. Fisher’s exact test showed no significant differences (P>0.05). All CEM specimens (100%) formed HTB, which was irregular in all cases. In 7 of 10 teeth in BAG, HTB formed and was irregular. Fisher’s exact test revealed no significant differences between the two groups in this regard (P<0.001). Both CEM and BAG are suitable DPC agents in terms of HTB formation and pulp inflammation scores.

In this study, the results of using MTA and propolis in the pulpotomy of primary molar teeth are evaluated clinically and radiographically. Methods and Methods: A total of 25 healthy 4 to 8 year old children each having two carious primary molar teeth in one arch, based on inclusion criteria were selected. In each child, random assignment of the pulpotomy medicaments was done as follows: Group I, MTA in one side; Group II, Propolis in another side. All the pulpotomized teeth were evaluated at 3, 6, and 9 month clinically and radiographically, based on the scoring criteria system. Finally data was analyzed using GEE analysis. Results showed that the effects of treatment and time on two scores were tested. Based on the results of this model, the chances of having clinical score 2, versus score 1 are about 2.7 times higher in MTA treatment than in propolis (P=0.001). Similarly, the chance of having a clinical score 2 relative to its one, at 9th month is approximately 6.8 times higher than the 3th month (P=0.000) and at 6th month is approximately 2.8 times higher than the 3th month (P=0.005). The chance of having higher scores of radiographies in treatment of propolis is approximately 6.5 times than that of MTA (P=0.000). Also, the chance of having higher scores of radiographic index at 6th month is approximately 5 times and at 9th month is approximately 27 times more than the 3th month (P=0.00). Based on the results of this experimental study, teeth treated with MTA showed more suitable clinical and radiographic results as compared to propolis at 9 months follow-up.

One of the major challenges in dental practice is dental complaints that majority of complaints resulted in criminal prosecution and the legal practitioners. The aim of this study was to investigate the patients’ complaints on the diagnosis and treatment plan, dentist’s behavior, treatment charge, and management unlike the behavior of medical affairs, lack of enforcement in Tehran Medical Council between 2005-2011.
We referred to the Medical Council in order to obtain permission for evaluating complaints of dentists in Tehran. All files in units of prosecutors, magistrates and judicial committee were evaluated. Data were analyzed using spss version16 software.
The results showed that the highest percentage of complaints was related to the how treatment was managed (41.7%) and the lowest percentage of complaints were about the dentist's diagnosis and treatment plan (2.9%).
Based on the results of this study, with dentists’ awareness of the existing rules and strict supervision, occurrence of complaints on the dental treatment can be prevented.

Injection is one of the most stressful dental procedures. The purpose of this study was to investigate the effect of video glasses in reducing anxiety and pain during inferior alveolar nerve block injection. This experimental study was performed on 40 children 6-8 years old. Children were randomly assigned to two groups. Each group was treated in three sessions. Children’s inherent anxiety was assessed in the first session and prophylaxis and fluoride therapy was performed for all children without anxiety. In the second session in the first group, injection was applied with glasses and in the second group, injection was applied without glasses. In the third session, in the first group injection was applied without glasses and in the second group, injection was applied with glasses. Visual analog scale pain assessment methods were used. Assessment of anxiety was done using the Modified Children Dental Anxiety Scale. The data were analyzed with Mann-Whitney and using SPSS 15 software. Average pain in the first group of video glasses was 1.89+_0.65 that this amount increased in the second session without glasses to 3.00±0.81. In the second group, the mean pain in the first session without glasses was 3.05±0.60 and this amount in the second session with glasses declined to 2.05±0.60. The difference between the two sessions in the two groups was statistically significant (P <0.001). Based on our findings, the use of audio-visual glasses is effective in reducing pain and anxiety during dental treatments.

Back ground and Microbial dental plaque is the main factor of periodontal disease. Antimicrobial effects of magnolia bark have been studied in vitro and also by using sugar-free chewing gum. The aim of this study was to evaluation antimicrobial effect of a mouthwash made from magnolia bark on the reduction of dental plaque using a periodontal parameter called Oleary plaque index. In this clinical trial study, initially a hydroalcoholic extract of Magnolia grandiflora bark was obtained. With regards to the MIC of the Magnolia extract for Streptococcus mutans and Stereptoccocus sanguis, a 0.3% mouthwash was obtained from the extract. Twenty volunteers entered the study to use this mouthwash and were classified into category of poor and good health based on their plaque percent index. OLeary index parameter was calculated in four stages. A placebo mouthwash was used as a control in this study. The findings were analyzed statistically using unpaired and paired t-tests. Results and In each round of magnolia mouthwash administration, percentage of OLeary index statistically showed a significant difference between the phase of mouthwash consuming and the resting phase. Also, the plaque percent index showed a significant difference between the magnolia mouthwash group and the placebo one (p<0.005) and the mouthwash was more effective.

Dental caries is the most common human infection. The most important indicator of dental caries is DMFT. Control of dental caries requires prevention programs. Prevention needs full knowledge of the possibilities that can be achieved through epidemiological studies. The aim of this study was to compare DMFT index in 8-12 year retarded students in special schools in Zahedan city with healthy subjects and evaluation of its relationship with factors such as age, sex, and educational level.

This descriptive, cross-sectional study was performed on 200 students including 100 healthy students and 100 mental retarded students. 50% of them were female and 50% were male. The sampling was randomized stratified. A questionnaire was completed for each student and DMFT index was measured by clinical examination according to WHO criteria. The data was analyzed using SPSS19 and t- test and ANOVA. Significant level was 0.05 and correlation coefficient Pearson was obtained.

The mean DMFT index was 2.92 ± 1.67 in normal students and 4.03 ± 1.92 in retarded students. DMFT in mentally retarded children had a significant relationship with age. In mentally retarded children, DMFT had no significant correlation with other studied variants.

Based on this study, the Health index of mentally retarded children is lower than WHO standards.

Statement of the Problem: With the recent focus of researches on the development of non-invasive treatment modalities, the non-invasive treatment of early carious lesions by remineralization would bring a major advance in the clinical management of these dental defects. Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is considered to be effective in tooth remineralization. The aim of this in-vitro study was to compare the effects of whey and CPP-ACP in increasing the enamel microhardness. Microhardness of 30 sound human permanent premolars was measured before and after 8-minute immersion of samples in Coca-Cola. The teeth were then randomly divided into 3 groups and were immersed in artificial saliva, whey, and tooth mousse for 10 minutes. The changes of microhardness within each group and among the groups were recorded and analyzed using paired t-test. The microhardness increased in each group and between the groups; this increase was statistically significant (p= 0.009). The effect of whey on increasing the enamel microhardness was more than that of tooth mousse.

Dental caries is an infectious disease that can be prevented in several ways. The aim of this study was to compare the efficacy of sodium fluoride mouthrinse and nano- hydroxyapatite (nano-HA) for the remineralization of incipient caries. After obtaining different concentrations of nano-HA (0-2-5-10%), 60 sound premolars fixed in acrylic blocks were coated with nail polish except for one surface. Ten teeth (control group) were stored in distilled water and the remaining 50 samples were demineralized by immersion in 13 ml of 0.1 M lactic acid and 0.2% poly acrylic acid for 48 hours. Their microhardness was then measured and compared to that of the control group. Next, the 50 test teeth were randomly divided into 5 groups of group1 (negative), group 2 (2% nano-HA), group 3 (5% nano-HA), group 4(10% nano-HA) and group 5 (0.2 NAF mouthrinse). The microhardness of the teeth was measured after 12 hours of immersion in the above-mentioned solutions. Data were analyzed using repeated measures analysis of variance (ANOVA). Microhardness of all samples decreased significantly after immersion in the demineralization solution and increased following immersion in nano-HA and NAF mouthrinses; however, this increase was not statistically significant (P=0.711). Nano-HA and NAF mouthrinses can greatly enhance remineralization and increase tooth microhardness.

The aim of this study was to investigate the mechanical properties (flexural strength، micro-shear bond strength) and remineralizing potential of fissure sealants by adding various concentrations of β-tricalcium phosphate nanoparticles. This in-vitro study consisted of five experimental groups containing prepared nano-fisssure sealants (1-5 wt. % b-TCP nanoparticles) and two control groups containing a prepared and a commercial fissure sealant. Flexural/micro-shear bond strength values were measured using Zwick test machine. Cavities on sixty healthy premolar teeth were filled with the fissure sealants containing 0-5 wt. % of nano b-TCP. The samples were assessed for remineralization under scanning electron microscopy (SEM) and EDAX. Kolmogorov-Smirnov test، One-way ANOVA and Tukey''s Post Hoc analysis/HSD were used to analyze the data. There was no significant difference between the flexural strengths/elastic modulus of the 0-5 wt. % nano β-TCP groups (p>0. 05). The average flexural strength/elastic modulus of the prepared fissure sealant group (0%) was significantly higher than the commercial fissure sealant group (Clinpro) (p<0. 05). There was no significant difference between micro-shear bond strengths of the experimental groups (1-5 wt. %)، and between the commercial and the prepared (0%) fissure sealant groups (p>0. 05). Examining the samples under SEM showed a significant increase in thickness of the intermediate layer with increasing concentrations of β-TCP nanoparticles (p<0. 05). Addition of 1-5 wt. % b-TCP nanoparticles to the fissure sealants significantly increased the remineralization potential without affecting the mechanical properties.

Providing a safe and efficient dental treatment for a young patient is a challenge for the dentist and the child. The purpose of this study was to investigate the effectiveness, safety and acceptability of buccal midazolam in dental pediatric patients and to compare it with oral Midazolam. Eighteen uncooperative healthy children aged 2.5-6 years were randomized to each of buccal midazolam (0.3mg/kg) or oral midazolam (0.5mg/kg) at the first visit, the alternative has been used at the second visit in a cross-over manner. The study took place at pediatric dentistry clinic of Shahed University, Tehran, from November 2011 to June 2012. The patients` vital signs and behavioral scores were recorded. The patient, the operator and the observer were blinded to the applied medication. Post operatively, patients` and parents` satisfaction were assessed by Visual Analogue Score and a questionnaire respectively. The P-value was set at 0.05 for significance level. There were no significant differences in physiologic factors in the medication groups at time 0, 10, 20, 30 minutes and discharge. There was also no significant difference between the two groups in behavioral parameters. The majority of parents rated both sedative agents as “effective” or “very effective” and their children mostly were without anxiety or with minor anxiety. Buccal midazolam may be safely and efficiently used in sedation of pediatric dental patients.

File fracture is one of the main procedural mishaps in endodontic treatment. The aim of this in vitro study was to compare the fracture rate of three NiTi rotary systems; Hero 642, Mtwo and FlexMaster in artificial canals. Methods and Materials: In this study, bovine long bone was used. After primary preparation of bones, longitudinal sections with 4-cm diameter were cut and encoded. Subsequently, semicircular sections were prepared. A total number of 500 canals were created in the same way; the upper 3 mm of the canals were initially prepared with orifice shapers and then canals were filed with FlexMaster files sizes 25/0.02 and 25/0.04 to 13 mm of canal length. The prepared canals were assigned into 3 groups of the following systems: Hero 642, Mtwo and FlexMaster. Six selected instruments were used from each system; the files were applied 13 mm along the canals for 10 sec with manufacturer’s suggested speed and torque. The number of the canals prepared by each file before its separation was recorded; finally the data was analyzed with ANOVA test. Mean number of prepared canals in Mtwo, FlexMaster and Hero groups before file separation was 15, 25 and 32, respectively. Results of this study showed that the number of prepared canals by Hero 642 was more than FlexMaster and Mtwo systems.

Nanosilver has numerous applications in medicine due to its potent antibacterial activity. However, data regarding the bio-safety of its effective concentrations is scarce. This study aims to assess the toxicity of silver nanoparticles on human gingival epithelial cells under in-vitro conditions. This in-vitro study evaluated the toxic effects of filtered and unfiltered nanosilver solution on human gingival epithelial cells obtained from the Pasteur Institute of Iran using the methylthiazol tetrazolium bromide (MTT) assay(mitochondrial function)and membrane leakage of lactate dehydrogenase (LDH) at 24, 48 and 72h time points. The concentrations of silver nanoparticle solution used were 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20 and 50µg/ml. The MTT assay showed that nanosilver solution at high concentrations (20 and 50µg/ml) significantly decreased the viability of cells at all time points. The lower non-fatal concentrations at 24 and 48h were capable of causing cell death or significantly inhibit cell growth at 72h. The LDH assay demonstrated that death of epithelial cells only occurs at high concentrations of nanosilver (20 and 50µg) and no significant toxicity was seen at lower concentrations. Based on the results, silver nanoparticles have toxic effects on human gingival epithelial cells and this effect is time and dose-dependent.

Metallic nano-particles show exclusive biological، chemical and physical characteristic. The purpose of this research was to evaluate the effect of various amounts of nanosilver incorporation (0 (as control)، 20، 40، 80، 120، 200 ppm) on the mechanical Properties (compressive and flexural strength) of resin modified Glass ionomer Cement.

Based on ISO 4049 and ISO 9971 for polyalkenoid cements، 90 cases in each group were prepared for the flexural and compressive strength. Specimens in 6 groups with different amounts of nanosilver (20، 40، 80، 120 and 200 ppm) and control (Fuji II LC improved)، stored in distilled water at 37 ° C for 1 day and 30 days. Flexural strength، using a three-point bending method، Modulus of elasticity and the compressive strength were measured by universal testing machine (Zwick) with crosshead speed of 0. 5 mm/min. Data were analyzed using two-way ANOVA and Tukey post HOC test.

The flexural strength and modulus of various amounts of nanosilver incorporation of resin modified glass-ionomer cement were not significantly different (P>0. 05). The compressive strength of incorporating of20 ppm compared with control (P=0. 01)، 40 ppm (P=0. 02) and 80 ppm compared with control (P<0. 001) were increased. The flexural strength and compressive strength of Fuji II LC، containing nanosilver particles were increased after 1 day and 1 month significantly (P<0. 001).

Incorporation of 20 to 80 ppm nanosilver into Fuji II LC had increased mechanical properties compared to the original cement.

Iatrogenic furcal perforation is a procedural accident in endodontic treatments of primary/permanent teeth; prognosis may be favorable if a complete seal with biomaterial is immediately established. The purpose of this in vitro study was to evaluate microleakage of calcium enriched mixture (CEM) cement and ProRoot mineral trioxide aggregate (MTA) for sealing primary molar furcal perforations. This study was conducted on 38 extracted human primary molars. Furcation perforations were created in the pulp chamber floor. The teeth were divided randomly in two experimental groups (n=17) and two positive and negative controls (n=2). Perforations were then repaired with biomaterials. After 72 h, the teeth were submerged in 2% fuchsin dye solution for 24h. The samples were sectioned longitudinally and evaluated for dye leakage. Data analyzed statistically using ANOVA test. The negative and positive controls behaved as expected. Dye microleakage was observed in all experimental samples; however, there was no statistically significant difference between the microleakage of MTA (4.411±2.042 mm) and CEM (3.647±1.040 mm) groups (P>0.05). Based on the findings of this in vitro study, CEM and tooth-colored ProRoot MTA have similar sealing ability for furcal perforation repair of primary molar teeth.

Microleakage is one of the most important problems in dentistry. Varnish is commonly used to reduce microleakage. Nanotechnology has recently produced cosmetic dental materials with better mechanical properties. The aim of this study was to compare the microleakage of dental restorations using traditional varnish and varnish containing nano-silver. In this research study، for preparing a nano-silver varnish، nano- silver powders was added to soluble varnish with a certain weight standard. Then، 30 teeth were divided into three groups for each time period (3 days and 1 month): nano silver-containing varnish، varnish، and without varnish (control group). For each sample، two class 5 cavities were prepared (one side of the buccal and lingual) with appropriate dimensions and optimum turbine and in each cavity (except to control) suitable varnish was applied and the cavities was filled with amalgam. Then، the teeth immersed in water for 3 days and 1 month depending on related groups. After the appropriate time has elapsed، the teeth were thermo-cycled. The teeth were placed in 2% Fushin. The teeth were divided into two halves from the middle of class 5 cavity. The sections were evaluated by stereomicroscope and dye penetration was measured. The data were analyzed by Two-Way ANOVA and Tukey multiple comparison test. Tukey multiple comparison analysis showed that there was a significant difference between nano-silver containing varnish group and two other groups. Based on the results of this study، applying of nano-silver to varnish reduces microleakage in amalgam restoration.

Furcal perforations are one of the most challenging causes of endodontic failures. Several materials including MTA have been used for non surgical repair of these perforations. The aim of this study was to compare treatment outcome of furcal perforation treatment in primary molars using Root MTA and ProRoot MTA. This in vitro study was conducted on 54 primary first molars that were randomly divided into the two experimental groups of 24 teeth each and two control groups (n=6). After preparation of access cavities, perforations were made and the perforation areas were repaired using either Root or ProRoot MTAs. After staining and preparation of mesiodistal longitudinal sections, dye leakage was measured using a stereomicroscope. The data was analyzed by the Mann Whitney statistical test. Significant level was set at 0.05. The data indicated that the dye leakage of ProRoot MTA is significantly lesser than Root MTA (P=0.001). ProRoot MTA showed good sealing ability in repairing furcal perforations of primary molars.

Long delays in getting a paper published in a medical journal may affect motivation for research. The aim of this study was to evaluate the duration of the research, and the average interval between the completion of a research project and the publication of the research article in dental research journals.

In this cross sectional study, all eligible articles were collected and adjusted based on the reported intervals according to the month of publication. In this study, delay was defined as the interval between receipt of the paper and final modification >6 months, final modification and final approval >3 months and the time between final approval and publication >3 months. Name of the journal, authors, type of design, quality of materials (type and time of source, number of sources in English, Farsi, whether books or articles) and the project sponsor, were assessed to determine if any of these factors were associated with delay.

In this study, 7 journals and 509 articles were evaluated. 14.6% of the papers were delayed. Delay between receipt and final modification was noted in 31.2%, between final modification and final approval was observed in 3.3% and between final approval and publication in 11.2%. In 54.3 percent of papers, this data was not available. At all stages, type of journal had a significant role especially in the time between approval and publication.

Significant delays have been observed between receipt of papers and their publication in dental journals.

The main reason for failure in application of fissure sealant is its loss of bond to tooth and development of secondary decays. Nanoparticles of hydroxyapatite have convenient biologic properties and we can try to benefit from these characteristics by adding them to repair materials. The present study was performed with the aim to assess the effect of addition of various amount nanoparticles of hydroxyapatite on mechanical properties such as microshear bond strength and physical properties like curing depth and degree of conversion as well as evaluation of teeth enamel remineralization.

In the present laboratory experimental studydifferent weight percentages comprising 0% (control)، 1%، 3%، 5%، 10% and 15% of nanoparticles of hydroxyapatite with 50 nm dimensions were separately added to fissure sealant. Then degree ofconversiontest by Fourier Transform Infrared Spectroscopy (FTIR) and curing depth according to ISO 4049 standard were performed on prepared samples. For the microshearbond strength test 35 premolar teeth without caries were used. The substance properties measurement device (Zwick) was used to do the test. Remineralization of permanent teeth enamel was assessed by Scanning Electron Microscopy (SEM). Raw data obtained were statistically analyzed by normal distribution test (Kolmogorov-Smirnov)، one way ANOVA and Tukey Post Hoc.

Results showed that microshear bond strength and degree of conversion had no significant difference in various concentrations of fissure sealant containing hydroxyapatite nanoparticles (P>0/05). Between microshear bond strength and degree of conversion means of 3M commercial fissure sealant and usual fissure sealant there was no significant difference (P>0/05). Curing depth in concentrations of 10% (P=0) and 15% (P=0) statistically significantly decreased compared to previous groups (P<0/05). Curing depth of 3M commercial fissure sealant group was lower compared to conventional fissure sealant group (P=0) and the difference was statistically significant (P<0/05). A remineralized region on the surface between the fissure sealant and tooth enamel was observed by SEM. This region was more remarkable in higher concentrations.

Fissure sealant containing hydroxyapatite nanoparticles with effect on remineralization on the surface of tooth enamel can lead to reduction of micro-leakages and prevention of development of secondary caries while mechanical properties do not decline.

Formocresol is widely used in primary teeth pulpotomies; however it is known to have several side effects. The purpose of this study was to assess pulpal changes of primary teeth pulps after pulpotomy with sodium hypochlorite and formocresol. In this randomized clinical trial, 22 teeth were selected. These teeth were randomly divided into 2 groups (formocresol; n=11 and sodium hypochlorite n=11). Two months post-operatively teeth were extracted and pulpal responses were evaluated by recording the degree of inflammation and extent of pulpal involvement. Dentinal bridge formation was also evaluated. Finally the data was analyzed with McNemartest. The formocresol group demonstrated mild inflammation in 4 cases whereas sodium hypochlorite had mild inflammation in six cases. Severe inflammation was only found in 1 case in the sodium hypochlorite group, but it was present in 4 cases in the formocresol group. In sodium hypochlorite group there were no cases of necrosis, and dentinal bridge was found in 3 cases, unlike, the formocresol group which had necrosis but no dentinal bridge formation. Based on the results of this study sodium hypochlorite may be a suitable solution for conducting pulpotomy in primary teeth.