مجله دانشکده دندانپزشکی مشهد
سال چهل و هشتم شماره 1 (پیاپی 128، بهار 1403)

This study was conducted to evaluate the quality of life of undergraduate and postgraduate dental students attending Mashhad Dental School during the COVID-19 pandemic using the WHOQOL-BREF standard questionnaire.

Methods & Materials: 

This descriptive-analytic cross-sectional study was conducted from February 2020 to February 2021 in Mashhad Dental School. A questionnaire designed by the World Health Organization was used to collect the data. The WHOQOL-BREF questionnaire was distributed both in person and online through Survey.porsline.ir platform. A total of 571 students completed the questionnaire. The WHOQOL-BREF questionnaire is scored in four domains. Data were subjected to statistical analysis using SPSS 23. Independent samples t-test, one-way ANOVA, and Bonferroni''''s test were used for statistical comparison. The significance level was set at 5%.

In undergraduate students, no relationship was found between different domains of quality of life and gender. There was a significant relationship between residence and the domains of environmental health (P-value

Antral exostosis in the maxillary sinus generally causes changes in the sinus, and its expansion may complicate planned sinus lift procedures before implant placement in the edentulous posterior maxilla. Therefore, before planning implant surgery, it is necessary to evaluate the presence of antral exostoses and other abnormalities, especially in the maxillary sinuses. The aim of the present study was to investigate the prevalence of exostoses in the maxillary sinus through cone beam computed tomography (CBCT) images in a population of northern Iran.

In this descriptive analytical study, 1068 scans were examined. Several parameters such as the presence of exostosis, location, bilateral or unilateral, type of exostosis and type of bone were investigated. In the coronal, sagittal, and axial images, the presence of exostosis and its location in the maxillary sinus, and its appearance and symmetry were recorded. Then, the collected data were analyzed by SPSS version 20 software and the significance level was considered P<0.05.

In the present study, 1068 samples were evaluated, and exostoses were observed in 15 cases. Out of the 15 cases of exostosis observed, there were 4 cases of bilateral (26.7%) and 11 cases of unilateral (73.3%) exostoses. 9 cases were on the right, 2 cases on the left side and 4 cases were both on right and left sides. 9 cases were observed in the lower wall, 3 cases in the medial wall and 7 cases in the lateral wall. There was no significant relationship between gender and the presence of exostoses (P=0.427).

The most frequently encountered exostoses were of broad-base type. Therefore, dentists are suggested to evaluate the position and condition of the maxillary sinus before performing implant surgery.

Various stimuli may be extruded from the apical foramen and can harm the periapical tissue. Therefore, this study evaluated the effect of different final irrigation methods on the extrusion of debris and irrigation solution from the apical foramen.

Method and Materials: 

This experimental in-vitro study was performed on 44 mesiobuccal root canals of extracted human maxillary and mandibular teeth with a curvature of less than 25 degrees. First, they were randomly divided into four equal groups, including flat open end, side vented, bevel, and ultrasonic system. Then a cube of standard floral foam, with normal dimensions, was attached to each sample to simulate a partial resistance of periapical tissue. The amount of debris and solution extruded from the apical foramen was measured by weighing these floral foam cubes. Differences in extrusion of debris and detergent solution between experimental groups were analyzed by one-way ANOVA test.

Based on the obtained results, in the ultrasonic group, the difference in the weight of the extruded debris with the flat open needle group and the side vent needle group was significant ( P<0.001). In the open-end needle group, the difference in the weight of the extruded debris with the ultrasonic group, the bevel group, and the side vent needle group showed a statistically significant difference ( P<0.001).

According to the findings of the present study, the amount of extruded debris and solution from the lowest to the highest belonged to the irrigation with the one-sided needle, bevel, ultrasonic, and flat-open needle.

In this study, the effect of conventional in-person education and in-person education based on videos and posters on the level of knowledge and satisfaction of students was compared in the course of clinical applications of laser in dentistry.

In this comparative applied study, 66 dental students were divided into two groups to take the course on clinical applications of lasers. The first group underwent conventional in-person education, and the second group underwent in-person education based on learning aids. The data collection tool was a researcher-made questionnaire that the students completed after completing the course and included 15 questions in two fields, including knowledge level (9 questions) and satisfaction level (6 questions). The data were analyzed with SPSS software (version 24).  Independent sample T-test and chi-square test were used for statistical analysis. Significance level was set at 0.05. 

The mean and standard deviation of the knowledge and satisfaction scores of the students who completed the course through conventional in-person education were 24.06 ± 6.8 (out of 36 scores) and 17.09 ± 5.15 (out of 24 scores), respectively. The mean and standard deviation of the knowledge and satisfaction scores of the students who had taken the in-person education based on learning aids were 24.56 ± 7.05 and 17.73 ± 5.1, respectively. Statistical analysis did not show a significant difference between the two study methods (P<0.05).

Teaching the course of the clinical applications of lasers was not significantly different between in-person education based on learning aids and conventional in-person education concerning the students' level of knowledge and satisfaction.

Many types of maxillary expansion devices with different expansion rates are used in the treatment of maxillary arch constriction. This study aimed to assess the effectivenessof a new removable plate appliance to improve maxillary arch constriction in comparison to similar common devices.Methods and Materials: The present quasiexperimental study was conducted on 15 patients who had referred to the dental clinic of Birjand University of Medical Sciences between July 2020 and December 2021. In the case group, the maxilla was widened with a transparent removable plate made of thermoplastic plates without wire components. The information of patients in the control group (treated with the removable acrylic plate with a midline screw and wire components) was extracted from a similar study. Data were subjected to statistical analysis using SPPS version 25. T-test, Mann-Whitney and one-sample T-test were used to compare groups. P-value less than 0.05 was considered statistically significant. The average amount of monthly intermolar expansion was 0.871±0.552 and 1.156±1.09 mm in the case and control groups, respectively. The mean amount of monthly inter-canine expansion was 0.994±0.498 mm and 0.931±0.869 mm in the case and control group, respectively. The results indicated no significant difference between the two study groups in terms of intermolar expansion (P=0.07) and intercanine expansion (P=0.68). The degree of satisfaction with the treatment was significantly higher in the case group, compared to the control group (P=0.01). It seems that the transparent thermoplastic removable plate without wire components is not more effective in the treatment of patients with maxillary arch stenosis compared to the common model with wire components. However, the use of this new device can be effective in increasing patients’ satisfaction by maintaining the efficiency of treatment.

This study aimed cohort study aimed to evaluate the relationship between the depth of invasion (DOI) and the lymphocytic host response (LHR) in oral squamous cell carcinoma (OSCC) biopsies with various clinicopathological characteristics of the disease.

Eighty-seven OSCC biopsy samples were obtained and key patient data such as clinical stage, grading, nodal involvement, overall survival (OS), and disease-free survival (DFS) were collected. DOI was measured from the basement membrane to the deepest invasion point, classifying samples into low risk (DOI < 4 mm) and high risk (DOI > 4 mm) categories. Additionally, LHR in the DOI was categorized as mild, moderate, or severe. The Chi-squared and Fisher’s exact test and Kaplan-Meier analysis were used for data analysis. The significance level was set at 0.05.

The findings revealed that 43.7% of patients fell into the low-risk DOI category, while 56.3% were in the high-risk group. LHR levels varied, with 36.8% mild, 18.4% moderate, and 44.8% severe. Most patients were in stage IV (31%) and grade I (60.9%). A significant relationship was found between the high-risk DOI group and several factors: disease stage (p < 0.001), grading (p = 0.021), five-year OS (p=0.001), five-year DFS (p < 0.001), and lymph node involvement (p < 0.001). Moreover, a significant relationship existed between LHR and the disease stage (p = 0.003) and lymph node involvement (p = 0.001).

Incorporating DOI into routine histopathological reports could be beneficial in predicting OSCC prognosis, especially in early stages. This underscores the importance of histopathological evaluations in OSCC treatment planning, highlighting the value of DOI and LHR in understanding the disease's clinicopathological aspects.

Dentists often face challenges in maintaining adequate oral hygiene for orthodontic patients. Nowadays, there are many oral health applications available that, along with interactive education and reminders, ultimately lead to better oral hygiene and desired oral health. This study aimed to investigate the level of use of these applications by orthodontic professionals in our country.

Methods & Materials: 

The present study was a descriptive cross-sectional questionnaire-based study, conducted in 2022. Using a convenient sampling method, 188 orthodontic professionals were recruited from the country, and 101 of them completed the questionnaire with informed and voluntary consent. A questionnaire was designed and validated to determine the familiarity and use of education and reminder health applications by professionals, and the data were collected online. Descriptive statistics were used to report the results, and the relationship between variables was analyzed using the chi-square test at a confidence level of 95%.

Most of the specialists had some difficulty with maintaining the oral hygiene of their patients. According to the present study, in the case of poor oral health of the patient, more than half (53.5%) of them sometimes had to terminate the orthodontic treatment of their patients. However, the results of the study showed that the orthodontists almost never used oral health education and reminder applications. Instagram was recognized as the most commonly used social network by orthodontist.

The results of this study indicate the need for specialists to have an efficient method of educating and reminding orthodontic patients about oral health. Given the lack of awareness and use of available applications by specialists and the absence of a suitable Iranian application, investment in designing or upgrading health reminder applications tailored to the culture and needs of society is recommended.

Academic burnout in students is characterized by feeling tired of doing homework, having a pessimistic attitude towards education and academic courses, and a sence of academic incompetence. The present study aimed to investigate the role of social support and life satisfaction in academic burnout of dental students in Zahedan University of Medical Sciences.

In this cross-sectional study, 162 dental students attending Zahedan University of Medical Sciences entered the study. The sample was obtained using a census-based sampling method and according to the inclusion criteria. Data were collected using Breso Academic Burnout Questionnaire, Diener Life Satisfaction Questionnaire and Zimet Perceived Social Support Multidimensional Scale Questionnaire. Data were subjected to statistical analysis using SPSS version 18 and was analyzed using the independent T-test, ANOVA and linear regression analysis.                           

According to the results, 65.4% (106) of students were at high levels of academic burnout. The scores of social support (4.53± 0.84) and life satisfaction (13.38± 4.07) were also in the moderate range in most students. The analysis of the data did not show any significant differences in average social support, life satisfaction and academic burnout with gender and academic term (p>0.05), and the results of the regression analysis showed that life satisfaction and social support had an inverse and significant effect (β= - 0.156 and β= - 0.290) on academic burnout.

According to the findings of the current study, most dental students had a high level of academic burnout and social support and life satisfaction of most students were not at a desirable level. Since social support and life satisfaction have had a significant and inverse impact on academic burnout, ameliorating these two components can make a significant contribution to reducing the rate of academic burnout among dental students.

Finishing and polishing are important stages of composite restorations. Failure to polish will cause recurrent caries, plaque accumulation, and inflammation of the periodontium. This study evaluated the influence of diamond polish-pastes on the polish retention of the nanocomposites after pH-Cycling and tooth brushing.

Forty cylindrical specimens including nanofilled composite (FiltekZ350) and nanohybrid composite (Aelite) were subjected to 4 polishing methods in 8 groups (n=5). A reference under Mylar strip (M), sequence of Sof-Lex discs(S), Sof-Lex discs and diamond polishing paste (TDV) (ST), and Sof-Lex discs and diamond polishing paste (Ultradent) (SU). After finishing and polishing, the Ra and Rz were determined by a profilometer for the first time. Specimens were subjected to a pH-cycling regimen and 10,000 brushing cycle. New readings of the Ra and Rz parameters were obtained. All sets of data were subjected to one-way ANOVA, Duncan multiple range test, and T-test.

In Z350 composite, the analysis of variance test showed a significant difference between Ra1 and Rz1 of the four investigated groups (P=0. 002, P=0. 003). After pH-cycling and brushing, Ra2 values showed significant differences among the four investigated groups (P=0. 009). The Rz2 values were not significantly different among the four groups (P=0. 353). In Aelite composite, the analysis of variance test showed a significant difference between Ra1 and Rz1 of the four investigated groups (P<0. 000, P=0. 004). After pH-cycling and brushing, Ra2 and Rz2 showed significant differences among the four investigated groups (P<0. 000, P<0. 000).

Comparison of Rz and Ra in Z350 composite before and after pH-cycling and brushing indicated no significant difference. In other words, pH-cycling and brushing did not change the surface roughness. Aelite composite had higher Rz than Z350 composite before and after pH-cycling and brushing. Diamond polishing pastes had no effect on reducing surface roughness.

Aplasia and hypoplasia of the maxillary sinus are rare conditions that can cause symptoms such as headache and voice change. Most patients are asymptomatic, the purpose of this study is to evaluate quantitatively and the quality of the maxillary sinus in CBCT images was in a population from the north of the country.

The current descriptive study was an analysis that included 997 CBCT samples of the maxillary sinus. When the maximum horizontal or vertical diameter of the maxillary sinus is less than half the maximum diameter of the orbit on the same side, mild MSH. And when the maximum vertical or horizontal diameter of the maxillary sinus was less than half of the maximum diameter of the orbit on the same side and with the enlargement of the orbit on the same side, moderate MSH and the maximum vertical and horizontal diameter of the maxillary sinus was less than half of the maximum diameter of the orbit on the same side, severe MSH were defined Finally, the data was statistically analyzed using SPSS version 26 software.

Out of 997 samples examined in the study, 42 samples were qualitatively and quantitatively found to have sinus hypoplasia (4.2%).

Out of 997 samples examined in the study, 42 samples were qualitatively and quantitatively found to have sinus hypoplasia. Of the 42 hypoplasia cases, 25 were unilateral and 17 were bilateral. There was no statistically significant relationship between gender and age group with maxillary sinus hypoplasia.