مجله دانشکده دندانپزشکی مشهد
سال چهل و هفتم شماره 3 (پیاپی 126، پاییز 1402)

Periapical lesions develop in response to chronic stimulation of an infected root canal in the periapical tissue. Two of the most common periapical inflammatory lesions are periapical cysts and granulomas. A mast cell is a round to elliptical immune cell that originates from bone marrow stem cells and enters peripheral blood, secreting histamine, heparin, cytokines, and chemokines under the influence of triggers. The present study aimed to evaluate mast cell density in periapical cysts and granulomas.

This descriptive cross-sectional study was performed on 60 samples of periapical inflammatory lesions, including radicular cysts and periapical granulomas. Sections were stained with Giemsa and then the number of mast cells were counted in five random areas of the cyst and granuloma walls. The results were analyzed in SPSS software (version 23) using the Mann-Whitney test. P-value<0.05 was considered statistically significant.

The mean number of mast cells in the radicular cyst (6.073±4/6) was higher than periapical granuloma (4.627±5.4); nonetheless, no significant correlation was found (P =0.174).

The presence of mast cells suggests the major role of these cells in the inflammatory mechanism of periapical lesions. Based on the critical role of these cells in the development and spread of periapical lesions, incorporating therapeutic and pharmaceutical approachs to alter the function of mast cell degranulation may be helpful in arresting inflammation in the early stages or preventing the spread of lesions.

One of the factors affecting deciduous occlusion is infant feeding modes. The objective of this research was to identify and document the malocclusions that arise due to various approaches of infant feeding, and to assist in clarifying ambiguities surrounding skeletal growth complications that result from infant feeding practices.

This cross-sectional descriptive-analytical study was conducted in 2021 on 284 children with an age range of 4-5 years who were selected from kindergartens and preschools in Sari by cluster sampling and then systematic sampling. After obtaining written consent from the parents and recording the child's personal information in the demographic checklist, the surface of the teeth was cleaned with a sterile gauze and then examined. The relationship of deciduous molars, overjet and overbite, open bite, posterior crossbite, and the relationship of deciduous canines were recorded. Data analysis was performed by Chi-square and one-way ANOVA using SPSS software (version 22). P-values of <0.05 were considered statistically significant. 

Infant feeding showed a significant relationship with the mother's education level, as well as the parents' occupational status. However, feeding type showed no significant relationship with the child's gender, number of children in the family, age of the child, age of the parents, and duration of milk feeding. Mesial step and distal step patterns were significantly more frequent in deciduous molars of breastfed children and those fed with formula milk, respectively (P<0.001). Furthermore, the type of feeding was not significantly associated with overjet, overbite, posterior crossbite, and deciduous canine relationship.

Breastfeeding is regarded as the most complete method of feeding infants, which is also a predisposing factor for developing a mesial step deciduous dentition.

The notion of educational service quality is multifaceted and arises from the perceived variance between students' expectations from the educational system and the services they actually receive. The progression of universities has shifted from a quantitative phase to a qualitative one, and as such, it has become necessary to assess the quality of university services. This research was conducted to evaluate the educational service quality at Gorgan Dental School.

A cross-sectional descriptive study was conducted in 2021, among dental students attending Gorgan Dental School, Golestan University of Medical Sciences. Data were collected using the SERVQUAL model questionnaire, which was devised considering the five domains of service quality. Descriptive statistics and inferential statistics were used in SPSS 23 to analyze the data.

 A total of 103 students, with an average age of 23. 09±3. 31 years, participated in this study. Most of the students were female (59%) and the rest were male (44%). The average overall score of expected service quality was 4.52±0.49 and the overall average score of perceived service quality was 3.09±0.71. The overall average gap in service quality was -1.44±0.79. The greatest gap was noticed in the responsiveness domain (-1.58±1.05) and the least gap was found in the tangible domain (-23.1±0.92).

There was a gap in all aspects of the quality of educational services and related terms, which shows that the expectations of students have not been completely met. In order to resolve this gap, meticulous planning and effective management of educational services should be enacted.

This study aimed to evaluate the expression of epidermal growth factor receptor (EGFR) in oral leukoplakia with and without dysplasia and normal mucosa by immunohistochemistry.

In this study, 45 samples of oral leukoplakia with and without dysplasia of normal mucosa (15 samples per group) were selected from the archives of the oral and maxillofacial pathology department Mashhad dental school. Immunohistochemical evaluation of EGFR expression according to the manufacturer's instructions was performed. The percentage of immunoreactivity was recorded and compared by statistical tests (Chi-square One-way ANOVA Kruskal-WallisMann-Whitney U). 

There was a statistically significant difference among the three groups with regards to EFGR expression (P=0.001). Increased expression of EGFR from normal mucosa to non-dysplastic leukoplakia and dysplastic leukoplakia was observed. There was no statistically significant difference between dysplastic and non-dysplastic leukoplakia.

Increased expression of EGFR was recognized as a key contributing factor for malignant transformations from normal mocusa to non-dysplastic and dysplastic leukoplakia, therefore indicating its role in the carcinogenesis of oral mucosa.

In this research, thermomechanical analysis of a 3D model of dental bridge between the first mandibular premolar and first molar was analyzed in Ansys Workbench software.

The dental bridge made of lithium disilicate ceramic and type II gold alloy was subjected to fluid at 4°C and 60°C for 5 seconds at occlusal and lingual surfaces. Moreover, the static and impact loads were applied at the center of the dental bridge. The first static load was a vertical force, and the second static load was in the form of an oblique force at an angle of 45° with respect to occlusal plane, oriented towards the buccal side. The impact loading simulation was performed for an impactor with different kinetic energy normal to the occlusal plane.

The maximum thermal stress in the bridge and dental tissue at 4°C is obtained at more than 60°C, yet dependent on the coefficient of thermal expansion, the elastic modulus, and the temperature field. The maximum thermal stress in gold bridges is about 30% higher than in ceramic bridges. In addition, it was found that in the case when only vertical occlusion forces are acting, there is a significant underestimation of the maximum stress of 40% compared to the case of an oblique force. The stress intensity under rigid impactor with an initial kinetic energy of 2.2, 8.6, and 19.4 mJ was obtained at 1.35, 2.2, and 3 times the static stress, respectively, and the reaction force at roots was proportional to the magnitude of the kinetic energy of the impactor.

As evidenced in this study, the stress created in the dental bridge in impact loading and cold thermal stimulation is more critical than other loadings. On average, the ceramic dental bridge demonstrates less stress in both tooth tissue and dental bridge.

Bakground:

 Considering the role of fear and anxiety management in the success of treatment and the need for dentists to be familiar with anxiety control protocols, we assessed the level of dentists' exposure to patients with dental fear and anxiety and measured the use of anxiety management techniques in this shudy.

 This cross-sectional study was carried out on 360 dentists working in Isfahan City, Iran, in 2020. A 20-item researcher-made questionnaire was designed and validated. The first part of this questionnaire collected information about demographic characteristics, including age, gender, graduation year, and working hours per day and week. The second part included questions to assess dentists’ knowledge in identifying patients with dental anxiety and their management method, the frequency of their exposure to anxious patients in different age groups, and the frequency of using behavioral and pharmacological techniques to manage anxiety. The validity of the questionnaire was measured by calculating the content validity index and its reliability through test-re-test. The questionnaire was prepared electronically and distributed in dentists’ virtual groups. Data were analyzed by SPSS 22. Comparisons between dentists' performance and demographic indicators, such as work experience, gender, and age groups were calculated using Chi-square and correlation coefficients (α=0. 05).

 Out of 360 distributed questionnaires, 311 were filled out (response rate of 86%). The frequency of male dentists was 49. 8% (n=155), and the mean work experience was 10. 3±9. 3 (1-38 years). Overall, the mean of dentists' exposure to patients with dental anxiety was 27. 1±11. 23%. The frequency of using different anxiety control techniques was 82. 9% for Tell-Show-Do, 71. 6% for distraction, and 22. 5% for cognitive-behavioral techniques. The use of cognitive-behavioral methods in the control of dental anxiety showed a significant relationship with gender (P<0. 001). It was also found that medication administration was lower in women dentists (P<0. 001). Regarding the ability to control patients with dental anxiety, appreciably 80% of dentists with more than 20 years of experience reported their ability as very or relatively well.

 Despite the exposure of dentists to anxious patients in different age groups, their knowledge to manage them seems insufficient. They rarely used cognitive-behavioral techniques and muscle relaxation to manage anxious patients. The application of nitrous oxide, sedatives, and hypnotherapy was not very frequent. Therefore, the consideration of educational courses for dentists to identify and manage anxious patients for successful treatment and improve their health seems necessary.

The fabrication of provisional fixed restorations is one of the most important steps during a fixed prosthesis treatment. In cases which provisional prosthesis are required for a period longer than 14 days, discoloration is more critical. Due to the production and popularity of using Acropars acrylic resin for fabricating provisional prosthesis in the country, the comparative evaluation of color change of Iranian (Acropars) and Foreign (Trim) acrylic resins used for provisional restoration was conducted in an In vitro environment.

A total of 64 disc-shaped samples (32 samples for each type of resin) were prepared. The color characteristics of the samples were measured at baseline, before their exposure to 4 types of color solutions and the changes after exposure to the dye solutions (10, 20 and 30 days after exposure) were determined by the spectrophotometer.

The mean color difference (ΔE*) in Iranian acrylic resin in different solutions was in the unacceptable range and mean color difference (ΔE*) for Trim acrylic resin was in the acceptable range.

Acropras acryl underwent more discoloration compared to trim acryl

Adherence to the principles of professional ethics, rules and regulations of the medical profession and patients' rights are prerequisites for providing dental care. Therefore, the present study was conducted to investigate the level of ethical skills among Yazd general dental practitioners.

In this descriptive cross-sectional study, general dentists practicing in Yazd during January 2020-2021 were randomly selected and completed a sixteen-item Chambers Ethical Skills Questionnaire which contains four domains of moral sensitivity, reasoning, integrity and courage. Data were subjected to statistical analysis using SPSS Version. 24 and analyzed using t-test, ANOVA and Tukey test. The significance level was 0. 05.

A total of 100 dentists, including 41 males and 59 females with a mean age of 35. 58±9. 19 Years, participated in this study. The mean score of dentists’ moral skills was 18. 06±4. 40 out of 32. The mean score of moral sensitivity, moral courage, moral integrity and moral reasoning were 5. 68±1. 61, 5. 30±1. 58, 3. 91±1. 59 and 3±1. 87, respectively out of 8 scores in each domain. There was no statistically significant relationship between the mean score of moral skills and its domains with age, sex, work experience and mother's education (P-value>0. 05). There was a statistically significant correlation between the mean score of moral courage and father’s (P=0.005) education and place of dental care (P =0.037).

Considering the average obtained scores of dentists' regarding ethical skills, the necessity of organizing educational courses with the topics of ethical skills, especially in the domain of moral reasoning and integrity is necessary

Pain management has always been a challenge in dentistry and especially after endodontic treatments. Hence, this study aimed to evaluate the analgesic effect of an herbal medication containing ginger and pineapple extract, curcumin, and bromelain, called Anaheal Plus, after endodontic treatment, compared to Ibuprofen.

In this clinical trial study, 78 patients were randomly selected and divided into two groups. In group A, patients were asked to take 400mg Ibuprofen, whereas patients in group B,took Anaheal Plus before treatment. Pain intensity values were assessed and recorded using VAS scores. Pain was evaluated prior to endodontic treatment, as well as 6, 12- and 24-hours post-treatment. Mann-Whitney, Chi-square, Repeated measure ANOVA and Friedman tests were also applied to analyze the data.

The mean pain scores in groups A and B were 6.46±2.71 and 5.79±2.57 before treatment, 2.95±2.59 and 2.67±2.69 six hours after treatment, 1.49 ± 1.22 and 1.38± 0.79 12 hours after treatment, and 0.65± 0.31and 0.60± 0.28 24 hours after treatment, respectively. Statistical analysis showed no significant difference between Ibuprofen and Anaheal Plus groups in terms of the obtained pain scores during different time intervals.

The findings of this study revealed that both Anaheal Plus and Ibuprofen had similar effects in pain alleviation for patients receiving endodontic treatment. Therefore, Anaheal Plus can be considered as an alternative analgesic drug in endodontic treatment due to its fewer side effects in comparison with Ibuprofen

Pyogenic granuloma is a benign and non-neoplastic mucocutaneous lesion that has multiple causes and develops in response to local irritation, trauma, or hormonal changes during pregnancy. In the oral cavity, this lesion often involves the anterior of the maxillary gingiva, and rarely, the tongue, labial mucosa, and palatal mucosa are involved. The clinical appearance of the lesion was usually seen as a nodule with or without a base, with a smooth surface or lobulated surface. It is usually non-tender, but it can bleed on touch. This lesion may be seen in any size from a few millimeters up to several centimeters. It is more common in females. This case report presents a rare site of a pyogenic granuloma on the dorsal site of the tongue. Clinical symptoms, causes, differential diagnosis, histology of the pyogenic granuloma, and treatment were discussed in this case report.