Journal of Dental Medicine

Background and Aims: Due to high mortality rate and cost of smoking, WHO has emphasized on the role of dentists in smoking cessation among patients. The aim of the present study was to investigate the dental students, knowledge toward health consequences of smoking, their attitude towards smoking cessation activities, and their education programs in this field.
Materials and Methods: In this cross-sectional study, the target group was senior dental students at Tehran and Shahid Beheshti Universities of Medical Sciences, and Azad and Shahed Universities. A questionnaire was used to collect data in addition to background information, on the knowledge, attitudes, and education towards tobacco cessation counseling in dental practice was administered to the students. The sampling method was census. Data were analyzed using oneway Anova followed by Turkey HSD post-hoc test for pairwise comparison.
Results: Overall 138 students participated in this program (The response rate was 100%). Of the maximum achievable knowledge score (28), the average knowledge score in Tehran University was 22.8, in Shahid Beheshti University 20.31, in Azad University 22.31, and in Shahed University 22.16 (P=0.027) with significant statistical differences. However, But the average of attitude and education score of the students did not vary significantly (P>0.05).
Conclusion: Most of the students had sufficient knowledge about the risks of tobacco use and positive attitude toward tobacco cessation counseling. It was concluded that the students would only pay attention to the principals of smoking cessation counselling when they actually believe in them. Therefore, in order to improve the performance of students, training should be given on tobacco cessation techniques at the dental schools, thus, that students could play an effective role in tobacco cessation counseling for patients.

Management of internal root resorption is a challenge to the endodontists. If it is left untreated, it may lead to the destruction of the surrounding dental hard tissues. Despite, routine obturation techniques are often employed without considering the best technique to solve this problem. This study presented a case of internal root resorption and apical periodontitis affecting tooth 12 (FDI) in a 31-year-old female patient, with a history of crown preparation in that region. We managed it with EndosealMTA and gutta-percha. After 12 months follow up, the tooth was still symptomless and in function and healing of bone resorption occurred.

Background and Aims: The bleaching agents can lead to color and translucency changes in composite resins. Due to the increasing use of the nano composites and the silorane-based composites, this study aimed at examining the color and translucency changes of these restorations after bleaching agents.
Materials and Methods: In this experimental - laboratory study, 198 composite discs were divided into three groups of 66 specimens using three types of composite: the microhybrid composite Z250, the nanohybrid composite Z350 and the silorane-based composite P90. After acid etching, half of the specimens in each group were covered by a resin rebounding agent. Then, the color and translucency assessment was done by reflectance spectrophotometer, using CIE LAB system. Each group was divided into three subgroups of bleaching agents: the 40% hydrogen peroxide and 20% carbamide peroxide bleaching agents and the control group. After applying bleaching agents, the final color and translucency changes were assessed. Data were analyzed using Mann Whitney and Kruskal Wallis tests.
Results: The effect of composite and bleaching agent type and bonding agent were significant (P<0.001). The color changes in the microhybrid composite were higher than nanohybrid and silorane-based composites (P<0.001) (∆E>3.3). Also, the color changes by 20% carbamide peroxide were higher than that of hydrogen peroxide and control groups (P<0.001). The results of translucency changes were generally consistent with color-change measurements (∆E>3.3).
Conclusion: According to the present study, the most color changes appeared in the microhybrid composite and by 20% carbamide peroxide bleaching agent. Rebound samples were generally less affected by bleaching agents. The least color and translucency changes were related to nanohybrid composites.

Background and Aims: Various methods to induce anesthesia have been investigated in situations where the primary inferior alveolar nerve block (IANB) injections fail. The aim of this study was to compare the effect of synergic effects of anesthetic injection of prilocaine supplemental with that of lidocaine anesthesia in teeth with irreversible pulpitis.
Materials and Methods: This study was a parallel-controlled clinical trial on 58 patients with one mandibular molar tooth having irreversible pulpitis. The first anesthesia was injected with an inferior alveolar block with 2% lidocaine anesthesia. Patients who failed pulpal anesthesia were randomly divided into two groups; case and control groups. In the case group, IANB was injected with 3% prilocaine, and in the control group with 2% lidocaine anesthesia. Anesthesia after the second injection was evaluated by three methods of numerical evaluation of the patient's response to Electric Pulp Tester (EPT), the severity of the patient's response to the cold test, and the extent of pain during the onset of access cavity latency on the Visual Analog Scale (VAS). Statistical analysis was performed using T-test and Mann-Whitney tests.
Results: There was no significant difference between the two groups in terms of depth of anesthesia (P>0.05).
Conclusion: The results of this study showed that there was no difference between 2% lidocaine and 3% prilocaine in the depth of supplemental IANB anesthesia after failure of first IANB in mandibular molar teeth with irreversible pulpitis.
 

Background and Aims: Oral squamous cell carcinoma (OSCC) is one of the most prevalent oral cancers with increased risk in individuals younger than 40 years especially in developed countries. There are many evidences that people who have plenty of fruits and vegetables in their diets tend to have lower risk of cancer. In this study, we evaluated the anticancer effect of four medicinal plants of Otostegia Persica, Otostegia Michauxii, Otostegia Aucheri, and Hibiscus Sabdariffa on OSCC cell lines.
Materials and Methods: In this study, methanolic & dichloromethane extracts of the above medicinal plants were used in order to evaluate their effect on oral squamous cell carcinoma cell line in different concentrations and after 24 , 48 and 72 hrs by MTT assay test. Finally, the appropriate concentration for repeating the test were chosen.
Results: In this study, the mean amounts of IC50 for O. persica and O. Aucheri were less than the two other herbs and the least and most amount of IC50 were related to the dicloromethanolic extract of O. persica after 72 hrs and the water extract of H. sabdariffa after 24 hrs, respectively.
Conclusion: It was concluded that all of the plants evaluated especially O.Persica and O.Aucheri had anticancer properties and dichloromethalonic extracts of these plant were more effective than that of methanolic extract.

Background and Aims: Erosion is the chemical dissolution of a tooth by acid without bacterial involvement. The purpose of the current study was to investigate the effect of resin infiltration (Icon), MI paste plus, and Nd:YAG laser on the enamel microhardness.
Materials and Methods: 40 enamel samples were obtained from the third molar tooth. Primary microhardness was measured in all specimens. Then, erosion was created using hydrochloride acid on the surfaces of enamel and the microhardness values were measured. The samples were randomly divided into four groups. G1: MI paste plus, G2: MI paste plus+ Nd:YA laser, G3: ICON without etching, G4: ICON with etching. Erosion was induced again by hydrochloric acid and then subjected to thermocycling. Finally, the microhardness of the samples was measured. Statistical analysis was performed using SPSS23 software, one-way ANOVA, multiple Tukey and T-test comparisons. P<0.05 was considered as a significant level.
Results: The microhardness increased in the third stage compared to the second stage in all groups, which was statistically significant (P<0.000). Also, the comparison of the increase of microhardness among groups, except second group with the fourth group, was statistically significant.
Conclusion: All the materials used in this study significantly increased the microhardness of the eroded enamel.

Background and Aims: The vertical growth pattern of the face depends on several factors. One of these factors can be the muscle strength of the jaw. Maximum occlusal force (MOF) can be considered as an index to measure the function of the muscles of the masticatory system. Despite the various studies, the relationship between the facial pattern and muscle function is still controversial. According to soft tissue paradigm theory, muscle can affect the shape and form of bones of the jaw, face and head. The aim of this study was to determine the relationship between the maximum occlusal force and head and face growth pattern in dental students of Shahed University in Tehran.
Materials and Methods81 dental students (40 males and 41 females) were participated. MOF was measured with a loadcell designed for this purpose, and the anthropometric points of the face and head were measured with digital caliper. Two-way ANOVA and Tukey HSD tests were used to determine the effect of facial and head patterns on the maximum occlusal force. Statistical analysis was performed by SPSS23.
Results: The mean MOF in males was 480 N and in females 320 N. Head forms in our sample research were 54.32% Brachycephale, 32.09% Mesocephale, and 13.58% Dolicocephale. The form of the face was 23.45% euprosopic, 39.5% mesoprosopic, and 37.03% leptoprosopic. According to the statistical analysis, the relationship between the maximum occlusal force and leptoprosopic form of face was statistically significant (P=0.02). However, there was not significant relationship between the maximal occlusal force and none of the three type of head forms (P=0.813).
Conclusion: MOF was related to the leptoprosopic pattern of face, and these individuals had less bite power. No relationship between the maximum occlusal force and head forms and neither between the head pattern and facial pattern was found in this study. The maximum occlusal force in men was higher in all three facial patterns than that of women, although this relationship was not significant.

Background and Aims: Elastomeric chains are known as a current device with the purpose of dental movement in orthodontic treatments. The aim of this study was to compare the elastomeric behavior and force degradation rate between different elastomeric chains existing in Iran in different time durations.
Materials and Methods: 11 different elastomeric chains used in this study were: Class One, ASTAR, G&H, TSNPT, MIB (French and Chinese type), Ultra Chain and both American, Ortho Technology (simple and memory type). All chains were stretched upon to exert 150 g force and then force degradation rate in 6 time duration
(1, 3, 24 hours and 3, 7, 21 days) and modulus of elasticity (MOE) in 2 time duration (start and 21 days) were investigated. All Data were analyzed statistically by ANOVA, Tukey, Games-Howel tests.
Results: All chains up to the 21th day showed a significant decrease in MOE except for the G&H, ClassOne, simple orthotechnology and a significant force degradation except for the American (memory type). The most significant force degradation rate was in ASTAR gray (P<0.05) and the least in MIB (French), Ultra Chain, and American (P<0.05).
Conclusion: All chains showed significant time-dependent force degradation (mostly in the first day). Only, this rate was not significant in any time duration for the American (memory). In all groups, the most force degradation rate belonged to ASTAR gray and the least to Ultra Chain, MIB (French) and American after 21th day.

Background and Aims: Adding nanoparticles to dental composite resins, could reduce bacterial adhesion and secondary caries. Thermocycling can resemble in-vitro conditions to the oral environment. The aim of this study was to determine the effect of thermocycling on the microleakage of a mixture of copper oxide nanoparticles and flowable composite.
Materials and Methods: In this in-vitro study, 88 premolar teeth were divided into eight groups based on the application of copper oxide nanoparticles with concentrations of 0.1% and 0.3% w/w and thermocycling by 0, 1000, 5000 and 15,000 cycles. The occlusal grooves of the teeth were sealed with the mixture of flowable composite and copper oxide nanoparticles, and the teeth were thermocycled. Next, the teeth were immersed in methylene blue 2% solution for 24 hrs and were cut and the microleakage was evaluated by a stereomicroscope (hp/USA). Data were analyzed using Kruskal-Wallis and Mann-Whitney tests at the significance level of 0.05.
Results: In the groups with 0.1 % copper oxide nanoparticles, the mean microleakage increased significantly with increasing the number of thermocycling rounds (P=0.032). The difference in the microleakage between the groups exposed to 0 and 15,000 termocycling was significant (P=0.019). However, thermocycling had no significant effect on the microleakage of groups with concentration of 0.3% (P=0.780). The specimens subjected to the 0, 1000, 5000 and 15000 thermocycling in two concentrations of copper oxide nanoparticles showed no significant difference in the microleakage.
Conclusion: In groups containing copper oxide nanoparticles with a concentration of 0.1%, the microleakage increased by increasing the number of thermocycling up to 15,000 cycles compared to the control group. However, this did not have significant effect for the concentration of 0.3% copper oxide nanoparticles.

Background and Aims: A significant percentage of children with dental caries require, hospital dentistry and their parents do not have much information in this regard. The aim of this study was to determine the knowledge, attitude and practice of pediatricians in hospital dentistry in Isfahan Province.
Materials and Methods: This cross-sectional study was performed on 100 pediatricians working in Isfahan. The self-administered questionnaire included demographics of doctors and 19 questions for assessing the knowledge, attitude and practice of pediatric practitioners about hospital dentistry under general anesthesia. Raw data were analyzed by Chi-square test using SPSS software version 23.
Results: 100 pediatricians with an average age of 44.1±5.7 years (57% male) completed the questionnaire. 53% of the pediatricians had a high level of awareness about hospital dentistry and 42% about its related guides. 66% practitioners had a favorable attitude toward general anesthesia and costs, while 71% considered the parents' awareness were poor about hospital dentistry. Only 43% of pediatricians performed oral examinations in their daily visits, and 17% had a referral for hospital dentistry. Male pediatricians aged from 35 to 45 had a higher level of knowledge about hospital dentistry. The attitude and practice of pediatricians did not have a significant relationship with their age. Meanwhile, male pediatricians had better performance in oral and dental examination and referral for hospital dentistry (P=0.15).
Conclusion: From the results of this study, there is a need for a serious improvement in the level of knowledge, attitude, and practice of pediatricians in the field of hospital dentistry.

Background and Aims: Pregnancy is a period with hormonal and psychological changes affecting women’s oral health. The aim of present review study was to evaluate, elaborate and categorize factors affecting oral health status of pregnant women.
Materials and Methods: A literature search with the following keywords: pregnancy, “pregnant women”, “pregnant mothers” and “expectant mothers” , AND dentistry, “dental health” and “oral health” in PubMed and Scopus was performed from 2009 to 2019. Search results included 1435 articles which 467 duplicate studies were excluded. Finally, 30 articles were included in the study. Oral health outcomes were categorized and significant relationships with determinants and risk factors were reported.
Results: Most studies (70%) were performed cross-sectionally. Among the studied outcomes, dental visit, periodontal disease and dental caries were the most common. The most studied independent variables were socioeconomic factors and demographic factors, followed by behavioral and enabling factors. The lowest frequency was related to the systemic factors. Mothers’ education and age were examined more than other variables and in about 40% of studies had significant association with outcomes. Dental counseling was assessed in only 3 studies and in all three studies, the relationship with outcome was significant.
Conclusion: Socioeconomic, demographic and enabling factors could affect the oral health of pregnant women.

Background and Aims: Pulpal exposures originated from the external cervical root resorptions have major effects on the treatment and prognosis. Therefore, the aim of this study was performed to compare the two different imaging systems-digital radiography with PSP (Photostimulable Phosphor) sensor in three horizontal different views and CBCT (cone beam computed tomography) images to assess the pulpal exposure in simulated cavity of external cervical root resorptions that was performed in 1398 in the School of Dentistry of Azad University.
Materials and Methods: 40 intact maxilla anterior teeth with straight roots were included. Teeth were randomly divided to two groups (20 teeth with and 20 without pulpal exposures). Each sample was assessed using PSP digital radiography (in 3 horizontal angles) and CBCT image system, to detect the presence of pulpal exposures. False negative and false positive results in 2 imaging procedures were judged with ratio test.
Results: The results showed in CBCT (P.P.V=85.7%) and (N.P.V=89.5%), and in digital intraoral radiography (P.P.V=80%) and (N.P.V=80%) in proximal defects. Ratio test showed that there were no significant differences in the proximal defects (P<0.4).
Conclusion: The results showed that there were no significant differences in detection of exposure in the proximal surfaces between two imaging systems.

Background and Aims: This study aimed to collect reports and HIS in a web-based system due to the problems of paper recording of student activities in practical courses, as well as the lack of computers in the departments for observing graphs and treatment plans.
Materials and Methods: The initial graphic design of the website was done after the assessment of needs and the necessary planning for designing the website. The main template of the website was designed after consulting with the faculty and the designer company. A combination of HTML, CSS, JQuery, and Java script was used for static coding and what the user sees or interacts with. Then, the basic information entered the website and the content designer put the website in the designed layout. In the end, a sample hosting space was prepared and the website was fully provided to the professors and faculty officials to work with as an administrator and a user. They conveyed all their opinions and the corrections were made based on the feedback given.
Results: The use of the internet and software with a central database played a significant role in monitoring and evaluating the long-term information of the student and the evaluation of the entire department, universities, and patients in each region up to macro-national evaluations. This could give the expansion and advancement of science in addition to the central registration of documents and radiographs, as well as their ease to access.
Conclusion: The designed website was well received among the students and the attending staff. Introducing a web based logbook and HIS system can optimize the clinical teaching. These logbooks could help both students and staff saving time and resources, and to facilitate providing better personalized care for patients.

Conclusion: The high prevalence of TMD and related factors, such as a history of jaw dislocation, posterior edentulousness, earache, and clenching, requires attention to be identified and treat these problems.

Background and Aims: Survival of periodontal ligament (PDL) cells after avulsion is an important factor in treatment prognosis. Grapefruit Seed Extract (GSE) can be a proper environment for preserving periodontal ligament cells. The objective of this study was to analyze the effect of different concentrations of GSE on the proliferation of fibroblast PDL cells.
Materials and Methods: In this study, the undifferentiated PDL fibroblasts were obtained from two human premolars teeth and cultured in Dulbecco’s modified Eagle’s medium (DMEM). The cultured cells were exposed to different concentrations of GSE. The positive and negative control groups were cultured in fetal bovine serum (FBS) 10% and in a medium without FBS 10%, respectively. The plates were incubated for 1, 6, 12, 24, and 48 hrs. The PDL cell viability was assessed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Statistical analysis of data was accomplished using repeated measure ANOVA with Post HOC Tukey, P<0.05 was considered statistically significant.
Results: We found out that among different concentrations of GSE, 1:128 had the most impact on undifferentiated PDL fibroblasts. Although, the cell vitality was higher in the twelfth hour, 1:128 GSE and in the forty-eighth hour, 1:1024 GSE than the positive control group but they were not statistically significant (P>0.05). Furthermore, all the samples were similar to the positive control group in three of the five timeperiods (P>0.05).
Conclusion: GSE was more effective in fewer concentration and longer periods and it had no toxic effect on PDL cells. Therefore, GSE can be considred as a promoting medium in PDL regeneration of avulsed permanent teeth in the future.

Background and Aims: Knowing the depth and type of the teeth impaction with radiographic approaches can guide the clinicians into selecting the most appropriate treatment and prevent surgical complications. Therefore, the purpose of this article was to evaluate the prevalence of canine and premolar impaction in the digital panoramic view of patients referred to Rasht dental school in 2019.
Materials and Methods: This annalistic-descriptive cross-sectional study comprised patients who attended the Faculty of Dentistry, Rasht, Iran in 2019. Dental records and panoramic radiographs of 500 patients were reviewed retrospectively. Demographic information as well as the type and depth of impaction, involved jaw, and also, the associated pathological lesions were recorded. Data were analyzed with SPSS24 version with significant level of P<0.05.
Results: The findings revealed that among 500 individuals (300 (60%) were females and 200 (40%) were males), 35 individuals (7%) had at least one impacted tooth, 80% of impacted teeth were canines and the others were premolars. The most common impaction type, impaction level, and pathological lesion were mesioangular, B, and carries of the adjacent tooth, respectively. A significant relation was not observed between the type and level of impaction with the involved jaw (P=0.15, P=0.99) and also, the relation between the type of pathological lesion and gender was insignificant (P=0.85).
Conclusion: Functional and esthetic complications of impacted tooth can be prevented or declined by on-time radiographic screening.

Background and Aims: Dental aesthetics has become an important issue in contemporary society. This study was designed to evaluate the patients’ satisfaction with their dental appearance and tendency to improve dental aesthetics.
Materials and Methods: In this descriptive study, a questionnaire with 17 questions was used to collect data from 200 patients referred to the dental school of Isfahan University of Medical Sciences from April-July 2019. A valid and reliable self-administrative questionnaire consisted of questions about the appearance of anterior teeth, receiving cosmetic treatments, and favorite aesthetic dental treatments was designed and used. Data were fed into SPSS22 and analyzed by Mann-Whitney, Kruskal Wallis and Spearman correlation tests (α=0.05).
Results: Among the participants, 27.5% (n=45) were dissatisfied with the appearance of their anterior teeth and the major reason for this dissatisfaction was related to the tooth color (35.8%, n=71). It was also observed that approximately 84% (n=168) of the patients had a history of smile concealment because of their teeth appearance. Among cosmetic dentistry treatments, aesthetic restorations were more commonly used than other treatments (20.5%, n=41). However, the most desired cosmetic treatments were teeth whitening (78.4%, n=156). There was no significant relationship between the satisfaction with the appearance of teeth and interest in the orthodontic treatment with age and education level (P=0.6).
Conclusion: Teeth color was the most important factor determining the degree of satisfaction with the appearance of teeth. Most of subjects desired to receive an aesthetic dental treatment and teeth whitening was the most popular aesthetic dental treatment.

Background and Aims: Due to the review of general dental courses, it was necessary to assess the students' satisfaction with this curriculum. The aim of this study was the assessment level of students’satisfaction with the new educational curriculum of the Ministry of Health at the department of restorative dentistry of Tehran university of medical sciences in 2019-2020.
Materials and Methods: In this descriptive cross-sectional trial,72 sixth year dental students of Tehran University who passed the restorative dentistry courses based on the new curriculum were studied. A questionnaire was developed and for validity content assessment, it was presented to 5 professors and then revised. For reliability approval of the questionnaire, test-retest approach was used. The questionnaire was given to the 30 students of the main pilot group in one session and two-week later and agreement percentage and Kappa index were calculated.  After conducting the "test" process and re-testing, the "questions" were statistically analyzed using STATA software.
Results: The most level of satisfaction regarding to practicality of subjects was found for fundamental of restorative dentistry including principles of amalgam class I cavity preparations and restorations on the dentic (81.94% and 76.39% acceptable respectively) and the principles of amalgam classII cavity restorations on the dentic (72.22%). The least satisfaction levels were obsereved in the first and second theoretical restorative courses including tooth-colored restorations (47.22%), onlays and inlays (47.22%) and tooth-colored classII cavity preparations and restorations (48.61%). The amount (P-value or error of the first type) was reported in all questions>0.001.
Conclusion: Despite the limitation of this study, final-year dental students’ satisfaction of theoretical restorative dentistry courses was medium, while it was high for the fundamental and practical restorative courses of 2017 educational curriculum.