Search published articles


Showing 26 results for Sadegh

H. Razmi , M. Aligholi , Sd. Sadeghi ,
Volume 19, Issue 4 (6 2007)
Abstract

Background and Aim: Many studies have shown that microorganisms are the main cause of pulpal diseases and the main purpose of root canal therapy is their elimination from the root canal system. Antiseptic agents are used to reduce bacteria but their antibacterial activities differ from in vivo to in vitro studies and might be inactivated by dentin and its components in root canal space. This study was designed to investigate the effect of dentin on antibacterial activity of different antimicrobial agents.

Materials and Methods: In this experimental study, two antibacterial agents (sodium hypochlorite and chlorhexidine) with different concentrations were used in four experimental groups: Group 1: dentin, Group 2: demineralized dentin with EDTA, Group 3: dentin matrix and Group 4: dentin mineral component. The species used in this study was Entrococcus faecalis. Different concentration of agents were added to mixture of each experimental group and bacteria. At the baseline and after one and 24 hours, samples were collected and cultured. After incubation period, colonies were counted. Data were analyzed by Tukey test with p<0.05 as the limit of significance.

Results: 2% and 0.2% chlorhexidine, and 5% sodium hypochlorite solutions at the three studied times eliminated Entrococcus faecalis completely. 1% sodium hypochlorite eliminated all bacteria in 1h and 24 hs. Statistical analysis showed significant differences between experimental and control groups (P<0.05). Sodium 1% hypochlorite at time 0, could reduce bacteria significantly (P<0.05) but didn’t eliminate them completely.

Conclusion: Inactivation of intracanal antiseptics was not observed in this study. As elimination of bacteria occurred, application of these antibacterial agents are recommended in endodontic treatment. Further investigations on other antibacterial agents, other concentrations and shorter time intervals are recommended.


H. Moosavi, S. Sadeghi,
Volume 21, Issue 1 (14 2008)
Abstract

Background and Aim: Application of varnish and dentin bonding agents can effectively reduce microleakage under amalgam restorations. Also rebonding may show some effects on microleakage and its complications. The aim of this study was to evaluate the effect of liner/ adhesives on microleakage of Class V amalgam restoration with or without rebonding.

Materials and Methods: In this in vitro study Class V cavities were prepared on sixty sound human maxillary premolars with the gingival floor 1mm below the CEJ. Cases were divided into six groups of ten teeth each. Specimens in group 1 and 2 were lined with Copalite and Scotchbond Multi-Purpose (SBMP) respectively. In the third group (control) no liner was applied. The teeth were then restored with spherical amalgam. Specimens in group 4 to 6 received the same treatments but after filling, the interfaces of restorations and teeth were etched with 37% phosphoric acid gel, rinsed and dried. Adhesive resin of SBMP was applied over amalgam and tooth margins and polymerized (rebonding). Specimens were thermocycled, exposed to dye and sectioned. Microleakage was graded (0-3) using a stereomicroscope at X40 magnification. Data were analyzed with Kruskal-Wallis, Mann-Whitney and Wilcoxon pair wise statistical tests. P<0.05 was considered as the limit of significance.

Results: The groups lined with SBMP showed the lowest and the groups without liner the highest microleakage (p= 0.001). Significant difference was observed in microleakage mean rank of enamel and dentin margins (p=0.048). Rebonding with resin did not improve the seal (p> 0.05).

Conclusion: Based on the results of this study, total etch adhesive system had significant effect on microleakage of Class V amalgam restorations especially in cervical margin. Rebonding did not show a significant effect on microleakage.


Ezatollah Jalalian, Mona Sadegh, Niaz Bazghale, Shahrzad Sadat Javadpour,
Volume 25, Issue 2 (9 2012)
Abstract

Background and Aims: Adequate retention of the post is a prerequisite for the clinical success which might be affected by the type of root canal filling material. The aim of this in vitro study was to compare the effects of gutta-percha and Resilon on retention of quartz fiber posts.

Materials and Methods: In this experimental study, 44 maxillary central incisors were sectioned at the CEJ level and prepared endodontically using ProTaper rotary files. The specimens were then randomly assigned into two experimental groups (n=22): group R, the root canals obturated with Resilon and group G, the root canals obturated with gutta-percha. After preparing the post space and insertion of quartz fiber posts, the coronal 10 mm of the root was sectioned perpendicular to the long axis to produce disks of 2.3 mm thickness.Then the specimens were submitted to the push-out test (1mm/min) using a universal testing machine. The data were analyzed using Mann-Whitney U test.

Results: There was a significant difference between the retention of posts in groups R (7.08±5.1) and G (4.8±3.3) (P=0.04).

Conclusion: Quartz fiber posts showed significantly higher retention in teeth obturated with Resilon compared to those obturated with gutta-percha.


Masoomeh Hasani Tabatabaie, Ayob Pahlavan, Esmaiel Yasini, Mansore Mirzaie, Sakineh Arami, Hamid Kermanshah, Hamidreza Sadeghipour Roudsari, Seyed Hossein Bassir, Taher Akbari Saeed, Hamed Hasani,
Volume 25, Issue 3 (1 2012)
Abstract

Background and Aims: There is concern that leached components from dental composites may cause adverse changes in the reproductive health. This study aimed to assess the effects of leached components from a hybrid resin composite on the reproductive system of male mice.
Materials and Methods: In the present animal study, twenty adult Syrian male mice were divided into two groups of 10 mice each. In the test group, components which leached from samples made from Filtek Z250 resin composite into 75% ethanol were daily administered to the mice for 28 days. In the control group, the procedure was repeated in the same way as the test group but without placing composite samples in the solution. Then, the body weight, weights of paired testes, Gonado Somatic Index, sperm viability, sperm motility, epididymal sperm reserve and daily sperm production were recorded. Four male mice in each group were mated with untreated female mice for 10 days. After that, the number of pregnant females and number of infants were recorded. The data were analyzed using repeated measures ANOVA, Chi-square test and t-test.
Results: There was a significant reduction in the sperm viability and sperm motility of male mice in the test group compared to the control group (P=0.001). There was no any significant differences in other parameters between two groups (P>0.05).
Conclusion: This study showed that the leached components from resin composites cannot cause infertility but they could potentially cause some adverse effects on the reproductive system of male mice.


Omid Aminian, Zahra Banafsheh Alemohammad, Khosro Sadeghniiat Haghighi,
Volume 26, Issue 2 (5-2013)
Abstract

Background and Aims: Regarding the diversity of reported low- back pain among dentists in different countries and lack of control group in most of the previous studies, the purpose of this study was to compare low- back pain and related risk factors between male general dentists and pharmacists to determine the relation between dentistry and development of low back pain.

Materials and Methods: In this cross-sectional study, 261 male dentists were compared with 193 male pharmacists as a control group with Standardized Nordic Questionnaire (low back section). Subjects were at least one year in clinical practice after becoming qualified and did not suffer from connective tissue diseases and history of a traumatic event causing fracture in spinal column. The data were analyzed by Chi- square, T-test and logistic regression analyses.

Results: The prevalence of low back pain in the past 12 months was 54.8% in male dentists and 36.3% in male pharmacists (P=.001). Logistic regression analyses, adjustmenting for occupation, age, body mass index (BMI), smoking, working years and working hours per week, revealed that there was a significant association between being a dentist and having low- back pain (OR=2.54, P=0.001).

 Conclusion: Dentistry as a profession in male gender is associated with low back pain, independent of age, body mass index (BMI), smoking, working years and working hours per week.


Parvin Khadem , Seied Ebrahim Jabarifar , Hajiahmadi Maryam , Sadeghain Susan Susan , Mohamad Safaie ,
Volume 26, Issue 3 (8-2013)
Abstract

  Background and Aims: Oral health prepares us for daily activities without discomfort, and dissatisfaction. In this research, agreement level between parents and children aged 11-14 year-old in reporting child oral health-related quality of life was studied in Isfahan city.

  Materials and Methods: In this descriptive, analytical and cross-sectional study 128 pairs of parents and children aged 11-14 were selected with random sampling technique from schools in Isfahan and were asked to complete the relevant questionnaires. The questionnaires evaluated quality of life in four fields of oral signs, functional deficits and emotional and social health. In order to evaluate child-parent agreement, intra-correlation coefficient (ICC), Pearson’s correlation coefficient, Spearman’s correlation coefficient and intra-class correlation coefficient (ICC) were used (α=0.05).

  Results: The agreements between PPQ11-14 (parent perception questionnaire), CPQ11-14 (child perception questionnaire) and the related fields were 0.81, -0.67. The highest agreement level (ICC=0.83) was related to emotional health (excellent), followed by functional deficits (ICC=0.80), social health (ICC=0.69) and oral signs (ICC=0.64). Pearson's test showed significant correlations between CPQ11-14 and PPQ11-14 (r=0.81) (P<0.01).

  Conclusion: Although parents, especially mothers, may be used as proxies for their children in relation to quality of life and related fields, the views of both should be obtained in order to fully represent child oral health-related quality of life issues.


Amin Sobhani Mohhsen, Hasan Razmi, Mona Sadegh,
Volume 26, Issue 3 (8-2013)
Abstract

  Background and Aims: Successful root canal therapy requires knowledge of tooth anatomy and root canal morphology. For permanent mandibular premolars, great variety in size, shape and number of roots and root fusion expression has been reported in the literature. There is a wide variety of methods used in studies for evaluating the root canal morphology. One of these methods is Cone-beam Computed tomography (CBCT) that reduces the limitations of two-dimensional X-ray imaging, with less exposure in comparison with other 3D radiographies. Thus, this study was designed to evaluate the differences in the root and canal morphology of permanent mandibular premolars in an Iranian population by means of CBCT images.

  Materials and Methods: We searched a database of CBCT scans and evaluated 400 (20-60 years old) patients who met the inclusion criteria and teeth in this images (CBCT) were evaluated in three dimensions (Axial, Coronal and Sagital). Tooth length, number of roots, number of canals, canal type, root curvature and the effect of gender on any of the items mentioned were evaluated. Data were analyzed using T-test.

  Results: The average length of the first premolar of mandibular was 22.27 mm and second premolar was 22.28 mm. 98.4% of the first premolar and 98.2% of the second premolar were single root., and 87.3% and 93.1% were single channel. The incidence of number of canals based on vertochy divisions were:type 1: 90.7% and 90.8%, type 0: 2.2% and 2.8%, type 4: 3.3% and 3.1%, type 6: 1.4% and 2.1% and type 3: 2.5% and 1.5% respectively. In any case, there was no significant difference between males and females (P<0.001).

  Conclusion: Results indicate that dentists can obtain valuable information about the anatomy and morphology of the root canals using CBCT.


Ezatollah Jalalian, Mona Sadegh, Rana Mohamadi, Reihane Aghajani, Elnaz Shafiee,
Volume 27, Issue 1 (4-2014)
Abstract

  Background and Aims : The root fracture resistance of endodontically treated teeth depends on the types of posts. The aim of this study was to compare the effect of two types of bonded non-metallic posts with different elasticity modulus on the fracture resistance of endodontically treated teeth under compressive loads.

  Materials and Methods: In this in vitro experimental study, 20 fresh extracted mandibular premolars were selected and sectioned adjacent to the CEJ and then were endodontically treated. The specimens were randomly divided into two groups (n=10). After post space preparations, the fiber RTD Light posts (R.T.D, France) and zirconia coated fiber posts (ICE light, Danville) were cemented into the root canals. Composite resin (Lumiglass R.T.D, France) cores were built up. Aluminium foil was used to mimic the PDL, and the specimens were embedded in acrylic resin and tested in a Universal Testing Machine. A compressive load was applied at a 90 degree angle until fracture at a crosshead speed of 1mm/min. Data were analyzed using one-way ANOVA and T test .

  Results: The mean fracture resistance of R.T.D group was (1083.11 ± 156.74 (N)) and the mean of ICE light group was (865.18 ± 106.24 (N)). The highest mean fracture resistance was observed in RTD fiberglass and a statistically significant difference was observed between the two groups (P<0.001).

  Conclusion: FRC posts with zirconia coating due to unfavorable fractures of the teeth should be used with caution, and thus, fiber posts are preferred.


Arami Sakineh , Aghasadeghi Mohamadreza , Tabatabaie Masome Hasani , Darvishpour Hojat , Sheikhzadeh Sedigheh ,
Volume 27, Issue 4 (1-2015)
Abstract

  Background and Aims: Hepatitis B is an important infection route in dentistry requiring different disinfectants to prevent its transmission. The aim of this study was to compare the effects of chemical disinfectants (FD366, ISORAPID and 5% sodium hypochlorite 2/100) to remove Hepatitis B infections from the dental surfaces.

  Materials and Methods: In this experimental laboratory trial, serum of 10 HBV patients was poured into microtubes, FD366, ISORAPID and hypochlorite disinfectants were added to them. PCR experiments with viral diagnostic kits were used to diagnose the virus genome. Real time PCR was used to evaluate after incubation with the disinfectants. The reductions occurred in the viral load of Hepatitis B were statistically analyzed using Kruskal-wallis and Mann-Whitney U tests .

  Results: No significant antiviral efficacy was noted following the application of FD366 and ISORAPID disinfectants (P=0/07). However, hypochlorite showed the most efficacy to disinfect Hepatitis B and a significant difference was found among them (P<0.0001).

  Conclusion: Under the study limitations, FD366 and ISORAPID disinfectants did not show adequate efficacy to remove Hepatitis B virus. Hypochlorite was the most effective disinfectant.


Mohtavipour Seyedeh Tahereh , Seyedeh Saeideh Mohtavipour, Alieh Sadat Javadzadeh Haghighat, Shiva Sadeghi, Maryam Rezvani, Bahar Mahmoud Khalesi,
Volume 29, Issue 1 (7-2016)
Abstract

Background and Aims: Estimating the canal length is essential for reaching to a proper endodontic treatment. Any error and miscalculation in estimation of the working length, especially in curved canals, can result in complication during and after root canal therapy. The introduction of digital radiography has enabled us to measure curved canal length. The purpose of this study was to evaluate the calibration tool of Complementary Metal Oxide Semiconductor (CMOS) digital system in estimation of working length.

Materials and Methods: In this in-vitro study, 80 extracted molar teeth were selected and randomly divided into three groups based on angle and radius of canal curvature. A 5 mm orthodontic wire was placed on the lateral surface of the root. Conventional radiographs were taken after insertion of endodontic file in the apical third of root canals. Radiographic images were scanned and imported to the software of CMOS digital system. Two observers estimated the file lengths with and without using calibration tool of digital measurement software. The correlation between observers was evaluated and then data were analyzed using Paired T-test with 95% confidence.

Results: Overall agreement between observers was good. There was no significant difference between the mean values of calibrated measurement and true file length in the basis of canal curves (P>0.001). However, there was significant difference between the mean values of uncalibrated measurement and true file length in the basis of canal curvature (P<0.001).

Conclusion: The calibrated measurement of file length was more accurate than that of the uncalibrated file length measurement.


Ramin Mosharraf, Aref Sadeghian,
Volume 31, Issue 3 (11-2018)
Abstract

Background and Aims: In endodontically treated teeth, the fiber posts are used to retain a core restoration. The purpose of this study was to evaluate the effect of different resin cements on the bond strength of fiber reinforced composite posts to root canal dentin, and comparing the bond strength in different sections of root.
Materials and Methods: In this in-vitro experimental study, 48 extracted single-canal central incisors were endodontically treated. For the push out test, the posts were divided into 3 groups according to one of the following three different cement materials (n=16) (Bifix SE, Bifix QM, Rebilda). Three slices with a thickness of 2-mm were prepared of each root. The push-out tests were performed at a cross-head speed of 1 mm/minute using a universal testing machine. Data were analyzed by two-way and one-way ANOVA test followed by Tukey post hoc test (α=0.05).
Results: There was no significant differences between the mean push out bond strength of three experimental groups (P=0.650), but there were significant differences between the mean push out bond strength of root dentin regions (P<0.001).
Conclusion: Under the conditions of this study, there was no significant difference between the mean push out bond strength of 3 different resin cement systems. The coronal region of root dentin showed significantly higher mean bond strength values than that of the middle and apical thirds.

Roxana Sadeghamalnikraftar, Maryam Rezai Dastjerdi, Hemat Gholinia, Babak Amoian,
Volume 32, Issue 1 (7-2019)
Abstract

Background and Aims: Removable partial denture (RPDs) is a common therapy for rehabilitation of partialy edentulous patients while RPD causes a lot of periodontal problems. The purpose of this study was to investigate the effect of RPDs made in Babol dental school on the periodontal health of abutment and non-abutment teeth.
Materials and Methods: In this cross sectional study, 70 patients who were candidates for RPDs divided into four groups according to Kennedy classification. The following periodontal parameters were evaluated for abutment and non-abutment teeth, plaque index (PI), calculus index (CI), width of keratinized gingiva, bleeding on probing (BOP), periodontal pocket depth (PPD), tooth mobility (TM) and gingival recession. This clinical measurement was taken immediately before insertion of the RPD, then one, three, and six months later. These parameters were then analyzed using Mann-Whitney, Independent sample t-test, Covariance, Chi-square statistical tests.
Results: In Class I; the mean score for the width of keratnized gingiva (P<0.001), PPD (P=0.002), and BOP (P<0.001) of the abutment and non-abutment teeth were significantly different after 1 month. After 3 months there were significant differences with regard to the PI (P=0.01), width of keratnized gingiva (P<0.001), BOP (P<0.001) and PPD (P<0.001). After 6 months, only the PI, CI, and TM parameters were not statistically significant. In Class II; the mean score for width of keratnized gingiva (P<0.001) and PI (P=0.002) after 1 month, width of keratnized gingiva (P<0.001), BOP (P=0.02), PPD (P=0.05) and TM (P=0.03) after 3 months and width of keratnized gingiva (P<0.001), PI (P=0.04), BOP (P<0.001) and TM (P=0.03) after six months were statistically significant. In Class III; only gingival recession did not show any significant difference at 1 and 3 months later. The width of keratnized gingiva (P<0.001), PI (P=0.001), BOP (P<0.001) and TM (P=0.03) after 6 months were statistically significant.
Conclusion: This study showed that RPDs affect the periodontal condition of both abutment and non-abutment teeth, which can be reduced by more precise design of the prosthesis, periodontal follow ups and good oral hygiene.

Mohammad Najafi, Hassan Semyari, Rokhsareh Sadeghi, Fatemeh Mashhadiabbas, Fereshteh Shanei,
Volume 32, Issue 3 (11-2019)
Abstract

Background and Aims: Reconstruction of osseous defects is one of the ideal goals of periodontal treatments and dental implant therapy. Different biomaterials have been used for this purpose and many studies have tried to compare and introduce the best ones. The present study aimed to evaluate the effect of PDFDB (Partially Demineralized Freeze-Dried Bone Graft) and FDBA (Freeze Dried Bone Allograft) on the regeneration of rabbit calvarial defects.
Materials and Methods: In this experimental study, 48 similar defects with the diameter of 8 mm were generated in the calvarium of 16 rabbits. Two defects were filled with FDBA and PDFDB, while the other one remained unfilled as the control group. All defects were covered by collagen membranes. 6 and 12 weeks after surgery, the histologic and histomorphometric tests were performed to evaluate the following variables: the rate of new bone formation and its type, the amount of residual grafting material, degree of inflammation and pattern of bone formation. Comparison of osteogenesis percentage and residual biomaterial was performed by repetitive variance analysis, whereas qualitative variables were compared by Friedman non-parametric test.
Results: Regarding bone formation percentage, there was no statistically significant difference between three different groups at 6-week (P=0.33) and also at 12-week time points (P=0.98). The amount of residual material in the PDFDB group was significantly lower than FDBA (P=0.04) in the 6-week samples. However, this difference was not significant in the 12-week samples (P=0.41). Bone quality showed statistically significant difference between graft containing groups and control group after 12 weeks (P=0.01). It means, all samples in FDBA and PDFDB groups displayed lamellar bone after 12 weeks while in control group, only woven bone or a combination of woven and lamellar bone was seen.
Conclusion: FDBA and PDFDB demonstrated similar regenerating effect in the rabbit calvarial bone defects and hastened bone maturation compared to the non-grafted defects.

Arezoo Khabazian, Fateme Azarnoosh, Sayed Mohsen Sadeghi,
Volume 33, Issue 2 (8-2020)
Abstract

Background and Aims: Periodontal diseases are prevalent and are not only a threat to oral and dental health of patients and community, but also affect the quality of life associated with oral health. Therefore, the present study aimed to evaluate the effects of non-surgical periodontal therapy on the quality of life associated with oral health in patients with periodontitis and gingivitis.
Materials and Methods: 47 patients with gingivitis and moderate to severe chronic periodontitis referred to the periodontology department of Yazd Dental School in 2019 were studied. OHIP-14 validated questionnaire was used to assess the quality of life related to oral health. At the beginning of the study, both groups completed the questionnaire. Then scaling and root planning for periodontitis group and scaling for gingivitis group were done. Patients completed the questionnaires again 9-12 weeks after periodontal treatment. Data were analyzed by SPSS software version 22 using independent T-test, Chi-square, Mann-Whitney and Wilcoxon tests.
Results: The mean score of quality of life in patients with gingivitis was 19.18±11.68 before the treatment and 13.26 ±11.41 after treatment. The mean score of quality of life in patients with periodontitis was 23.29±9.80 before treatment and 13.95±9.68 after treatment. All the differences between groups before and after treatment were statistically significant (showing better quality of life after the treatment) (P<0.05). There was no statistically significant difference between the mean score of quality of life related to oral health in the studied patients according to the age and sex (P>0.05).
Conclusion: According to the results of this study, treatment of periodontal diseases improves quality of life related to oral health in patients with gingivitis and moderate to severe chronic periodontitis.

Noushin Khandan Dezfuli, Majid Sadeghpour, Mojgan Sarabi Nobakht, Elham Estabarghi, Kumarss Amini,
Volume 34, Issue 0 (5-2021)
Abstract

Background and Aims: Periodontitis is a common and inflammatory infectious disease that causes damage to the tissues supporting the tooth and consequent tooth loss. Periodontal disease is a multimicrobial and multifactorial disease and important anaerobic bacteria are involved in periodontal infection. TGF-1β is one of the growth factors and anti-inflammatory cytokines that play a crucial role in the repair of periodontal lesions. The aim of this study was to evaluate Tetra Arms-PCR with high sensitivity and specificity, which can be used to evaluate the genomic polymorphism among oral samples and show the relationship between TGF-1β and periodontal disease.
Materials and Methods: The present study was a case-control study in the periodontology department of Kerman Dental School. Sampling was done from 100 samples including 50 healthy individuals and 50 patients with microbial periodontal infection. Genotype was analyzed using DNA extracted from the blood of patients by PCR -ARMs-Tetra to determine the relationship between TGF-1β genomic polymorphism and periodontitis. Statistical analysis was performed with SPSS19 software and one-way ANOVA.
Results: The samples were culture positive, therefore, more than 65% of the isolated bacteria were anaerobic which included: Prevotella, Porphyromonas, Fusobacterium, Peptostreptococcus anaerobic. The results of Tetra PCR ARMs after sequence frequency were genotype CC allele (25%), CT allele (20%), TT allele (5%). Percentage of control group were CC allele (20%), CT allele (24%), and TT allele (6%). The frequency of C and T alleles in the patient group was 70% and 30%, and in the control group 63% and 37%, respectively with no significant difference between two groups (P=0.83).
Conclusion: According to the results of this study and the application of anaerobic conditions, forced anaerobic bacteria can be isolated from clinical specimens of oral infections and by Tetra Arms-PCR no significant relationship between TGF-1β genomic polymorphism and periodontitis was observed. In addition, therer was no significant difference in the frequency of alleles and genotypes between the control and patient groups.

Mostafa Motallebi, Maryam Sadeghipour, Nika Mehrnia, Mohammad Behnaz, Nahid Mohammadnia,
Volume 35, Issue 0 (5-2022)
Abstract

Background and Aims: Today, academic stress and subsequent test anxiety is one of the most important problems for the last year of high school students. In addition to systemic effects, stress can affect the level of oral health by disrupting oral health behaviors. The aim of this study was to investigate the relationship between stress and variables related to oral health in the final year of high school students prior to University entrance exam.
Materials and Methods: In this descriptive-analytical study, the level of stress and variables related to oral health in 180 students of the final year of high school in Tehran, in three time periods during the academic year 2018-2019, were measured by a questionnaire and one clinical examination. Data were analyzed by Friedman, Bonferroni and Generalized Estimating Equations using SPSS software.
Results: As the exam approaches, some variables related to the oral health, such as toothbrush usage pattern, daily sleep, fast food frequency, and sweet snack consumption, changed (P<0.05). Daily sleep changes were significantly associated with the stress changes (P=0.022). According to the results of the Repeated Measures Analysis, significant changes were observed between the average score of the "Cognitive Error" aspect of three times (P<0.001). Also, according to the results of the Bonferroni Test, significant changes related to the difference in the average score of "cognitive error" 6 months and 3 months before the entrance exam (P<0.001), 6 months and 1 month before the entrance exam (P<0.001), and 3 months and 1 month before the entrance exam (P<0.001) were observed. In all three cases, as the time of the entrance exam approaches, the score of "cognitive error" had decreased significantly. Considering that the lower score in this index indicates a higher level of test anxiety, the closer we get to the entrance exam, the higher the level of test anxiety in the "cognitive error" dimension
Conclusion: The academic stress of the national university entrance exam can affect some oral health variables such as daily sleep, however, it is not related to other variables.

Seyyed Peyman Shariatpanahi, Pouya Jamshidi, Maryam Sadeghipour Roudsari, Mohammad Hosein Khoshnevisan, Mahshid Namdari, Baharan Arshadi Fard, Sarvin Soleimanpoor,
Volume 37, Issue 0 (3-2024)
Abstract

Background and Aims: Nowadays, the requirement of any policy-making at the national and regional level is to know the level of knowledge of people about oral health and ways to prevent dental caries.  This study examined the habits, actions and economic level of elementary school students in Qazvin city in 2017-2018.  Also, the effects of peer group social network on behaviors related to oral health and obesity was investigated in order to find the way for interventions making it more effective in this social group.
Materials and Methods: In this descriptive-analytical study, 145 students participated. They were in the 3nd and 6th grades of elementary school in the academic year of 2017-2018. The questionnaire used in this study had 20 questions and 4 main sections. The main parts of this questionnaire included demographic characteristics, behavior and habits related to oral health, oral health knowledge of students and families, and socio-economic status. Data were collected through clinical examinations and through valid questionnaires and evaluated using SPSS and Excel software.
Results: According to the results of Pearson's correlation analysis, a significant correlation was observed between the health knowledge scores of individuals and their friends between both groups of casual and close friends (P<0.01). The correlation between the knowledge of individuals and close friends was significantly stronger (P<0.01). Also, there was a significant relationship between socio-economic status and behaviors related to oral health (P<0.05). There was also a significant positive relationship between the number of times close friends brushing their teeth in a social network (P<0.001). This connection was not observed in the friends’ network.
Conclusion: This study determined that close friends can be effective in determining the oral hygiene behaviors of elementary school students.

Negar Kamali, Farimah Sardari, Mostafa Sadeghi,
Volume 37, Issue 0 (3-2024)
Abstract

Background and Aims: The quality of sleep plays a significant role in the academic performance of dental students, especially in the clinical years. Identifying and treating students at risk of sleep disorders can reduce or limit the drop in academic performance. The purpose of this study was to determine the relationship between the sleep quality and educational performance of Rafsanjan dental Student-Iran.
Materials and Methods: The present study was a descriptive-analytical cross-sectional study that was conducted among all dental students in Rafsanjan University of Medical Sciences - Iran. This study was presented to all dental students in Rafsanjan by online questionnaire method on Pressline website. The questionnaire included demographic information and student number along with the Pittsburgh Sleep Quality Standard Questionnaire. The Pittsburgh Questionnaire examines the quality of sleep in the range of 0 to 21. The link of the questionnaire was made available to the students through Telegram, and the GPA of the total students was obtained by using the student number from the Vice-Chancellor of University Education. The data were analyzed with SPSS26 software. First, the data were analyzed with Smironov's kermograph test. The results of this test showed that the data distribution is not normal (P<0.05). Due to the non-normality of the data distribution, non-parametric tests such as K-score, Mann-Whitney, Kruskal-Wallis and Spearman were used.
Results: 151 students participated in the questionnaire of which, 73 were men (48.3%) and 78 were women (51.7%). The mean and standard deviation of the age of the subjects studied was 22.11±2.3 years. The overall average sleep quality score of dental students was equal to 8.13, which according to the questionnaire, students experience poor sleep quality. 86.1% of students had poor sleep quality. Examining the correlation between the sleep quality and academic performance showed that there was no significant relationship between them. Sleep quality had no significant relationship with gender, marital status, place of residence, and entry year (P<0.05).
Conclusion: The results of the present study showed that majority of dental students in Rafsanjan had low sleep quality. Although, there was no relationship between the quality of sleep and academic performance, it seems necessary to pay attention to the sleep status of these students in order to improve their sleep quality, which is an important factor in improving their health by administrators and Rizan health program.

Mostafa Sadeghi, Niloufar Jafari, Mohammadhossein Kafi, Ali Rostami,
Volume 38, Issue 0 (4-2025)
Abstract

Background and Aims: The development and regular use of adhesive systems has started to revolutionize many aspects of restorative and preventive dentistry. The success of adhesive restorations highly depends on correct application of them. Therefore, the present study was conducted with the aim of determining the knowledge of dentists in Rafsanjan city (Iran) in choosing correct dental adhesive systems in 2023.
Materials and Methods: In this cross-sectional descriptive study, all dentists working in Rafsanjan city were included. The data was collected by a valid and reliable electronic questionnaire, which included two parts of demographic information (gender, age, place of work and year of graduation) and the 12 multiple-choice questions aimed to assess respondents' knowledge regarding the selection of dental adhesive materials in combination with self-cure or dual-cure composites, anterior and posterior composite restorations, fiber posts, fissure sealants, primary teeth, anterior composite veneers, ceramic laminates, and non-carious cervical lesions. The scoring of this questionnaire was as follows: 0 to 3 correct answers = Low level of knowledge; 4 to 6 correct answers = Moderate level of knowledge; 7 to 9 correct answers = Good level of knowledge; 10 to 12 correct answers = Very good level of knowledge.  The four answer choices included "etch-and-rinse (three-step)", "etch-and-rinse (two-step)", "self-etch (two-step)", and "self-etch (all-in-one bottle)". Then data were analyzed by parametric tests (ANOVA, t-test, and Pearson). The significant level was considered as P<0.05.
Results: Out of 91 dentists in Rafsanjan, 79 (86.8%) participated in the study, of which 35 (46.3%) were men. The average work experience was 3.49±3.96 years for men and 2.98±3.73 years for women. The average knowledge score was 4.38±2.16 out of 12 (4.29±2.23 in men and 4.45±2.12 in women). The results showed that there was no significant relationship between the knowledge score and the gender, age, work experience, and workplace (P>0.05).
Conclusion: According to the results which indicated the insufficient knowledge of dentists in  choosing correct dental adhesive systems, it is suggested to pay more attention on teaching in this field at the dental schools. For graduate dentists, new and practical information about the choice of adhesive systems should be provided by continuous education programs.

Negar Sarami, Sousan Sadeghian, Mehrdad Honarmand,
Volume 38, Issue 0 (4-2025)
Abstract

Background and Aims: Over the past two decades, the use of mini-screws in orthodontics has become increasingly common. Various factors such as design, length, diameter, and insertion angle of the miniscrew, as well as the quality and thickness of the patient's bone, would influence the success and stability of miniscrews. This study aimed to investigate the effects of miniscrew shape, cortical and cancellous bone thickness, and insertion/removal torque on the stress distribution in the mandibular bone surrounding the miniscrew.
Materials and Methods: This study was conducted using finite element analysis (FEA). Bone thickness parameters were extracted from the literature, and the mandibular bone along with cylindrical and tapered miniscrew models were simulated using ABAQUS software. By altering the relevant variables, the resulting stress were evaluated.
Results: An increase in both insertion and removal torque led to a corresponding rise in the stress around the miniscrew. Stress variations were more pronounced in tapared miniscrews in response to the changes in bone thickness and torque. The influence of cancellous bone thickness on stress distribution was found to be minimal.
Conclusion: Although, the tapered miniscrews offer greater retention and stability compared to the cylindrical types, their heightened sensitivity to variations in parameters such as bone thickness and torque necessitates cautious application.


Page 1 from 2    
First
Previous
1
 

© 2026 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by: Yektaweb