مجله دندانپزشکی دانشگاه علوم پزشکی تهران
سال سی و ششم شماره 1 (پیاپی 108، بهار 1402)

Journal of Dental Research is among the dentistry journal with the highest impact factor. This study aimed to map the most important topics for journal editors and readers.

The world's active research topics in the field of dentistry related to the Journal of Dental Research in the last 5 years were extracted from SciMapper's SciTrends. Also, we clustered the most cited papers in that journal to show the most important research topics for the journal editors and readers.

We identified and mapped 11 active international research areas in the field of dentistry and related to this journal. Among 146 faculty members of the school of dentistry, 12 had at least one article related to the most active research areas in the journal. In this regard, they had similar articles elated to the 7 clusters out of 13, but their articles are mainly related to the clusters 7 and 19. Among the investigated faculty members, nine had directly collaborated with 21 authors of the mapped clusters. Moreover, 12 faculty members could also connect to the 126 authors with articles in that journal through their scientific collaborators.

One way to publish in a top international journal is to know the most active and interesting research areas for the journal editors and readers. About 8% of the school of dentistry faculty members at Tehran University of Medical Sciences had some research related to the Journal of Dental Research.

The surgical removal of mandibular third molar is frequently accompanied by significant postsurgical complications, and different protocols have been described to decrease such complications. The aim of this study was to compare the postoperative complications of mandibular impacted third molar removal with two conventional rotary and piezoelectric methods.

In this study 27 patients with bilateral mandibular impacted third molars were selected. The patients’ teeth were extracted by the piezoelectric method on a random side and the opposite tooth was extracted by conventional rotary technique. On operation and post operation days, edema, pain, and mouth opening were assessed. The duration of each operation was also measured. Data were analyzed by Mann-Whitney test and independent t-test.

The mean duration of operation in the rotary group was less than that of the piezoelectric group, which was statistically significant (P=0.001). Pain was significantly higher in the rotary group on days 0 to 5 (P<0.05). Whereas, difference in pain on day 6 was not statistically significant (P=0.067). There was no significant difference between the two groups in each day after surgery regarding mouth opening (P>0.05). Edema was significantly higher in the rotary group on the first, third, and fifth days after surgery (P<0.05). Also, edema was higher in the rotary group on the seventh day after surgery, but not statistically significant (P=0.076).

According to the results of the present study, it can be concluded that pain and swelling in patients after impacted tooth surgery using time consuming piezoelectric technique can be reduced.

Background and Aims Guided endodontics is a new technique that is now evolving. It is used in many treatments, especially in access cavity preparation and locating root canals in teeth with pulp canal obliteration (PCO), microsurgical endodontics, and fiber post removal in retreatments. In addition, this technique is independent of operator experience, requires less treatment time for the patient, and is more precise and safer than conventional endodontics. This technique involves the use of cone beam computed tomography imaging (CBCT), tooth surface scanning, and special software to provide guidance for performing endodontic treatment in a fast, safe, and minimally invasive manner. This review article aims to introduce guided endodontics and to describe its technique, advantages, and limitations.

Management of pain and inflammation after third molar surgery is an important challenge of this treatment. Various medications have been proposed for pain control after surgery. Comparing the effectiveness of various drugs used in this field can improve dentists' clinical decisions. The aim of this study was to compare the effect of Ketorolac and Gelofen on pain relief in patients undergoing third molar surgery.

This randomized single-blinded clinical trial was performed on 140 patients who were divided into two groups of 70 after receiving the ethical code. The first group was prescribed 400 mg Gelofen capsule for 1 week, while the second group was prescribed 30 mg ketorolac ampule for 1 week. Then, using the visual analog scale (VAS), the patient’s pain was recorded 48 hours, 1 week, and 2 weeks after surgery. Data analysis was carried out using SPSS20 software by descriptive analysis of the results. Ki-square, T-test, and variance analysis were also used for analysis of variables.

The pain level in the ketorolac group after 48 hours, 1 week, and 2 weeks following surgery was significantly less than Gelofen group (P<0.01). Ketorolac effect on pain was irrelevant to the gender, age, and type of tooth variables.

From the results, it was concluded that Ketorolac had greater effect on pain relief after third molar surgery than Gelofen.

The evaluation of the results of health transformation plan in dentistry, which started in March 2016 with the aim of improving oral and dental health, is extremely important in order to improve planning for future actions. Therefore, the purpose of the present study was to evaluate the effect of the health transformation plan on common oral health indices in Guilan province in Iran.

This cross-sectional analytical study was performed using the Health Deputy of Guilan University of Medical Sciences data and results of the general population and housing census of the 2010 and 2015. Data analysis was done using Ordinary Least Squares regression method, considering dependent variables including DMFT, dmft and periodontal disease indices (CPI) and independent variables including gender, education, urban or rural residence, percentage of 13-year-old population, illiteracy rate, fertility rate and being or not in the transformation plan, to investigate the difference between the two groups before and after the implementation of the transformation plan in terms of variables and to examine the relationship between independent and dependent variables. Finally, data were analyzed by STATA SE software version 15.

The health transformation plan did not have a significant relationship with the change of DMFT and CPI 2 to CPI 6 indices, but had succeeded in reducing dmft and CPI1 (P<0.05), which reduction in CPI1 index was not desirable.

It seems that despite the extensive activities of the health transformation plan in dentistry in the field of prevention and treatment, there is still a need for more changes, especially in terms of culture and education. Also, there is need to provide more facilities for access to services by all sections of the society, especially the weak sections for healthcare.

Considering the regulatory role of vitamin D3 in the immune system, this vitamin may be able to prevent autoimmune diseases by modulating the immune system, so this study was conducted with the aim of comparison of the serum level of vitamin D3 in patients with oral lichen planus and healthy persons.

In this case-control study, the serum vitamin D3 level of 80 people, including 40 patients referred to Guilan dental school who were suffering from oral lichen planus and 40 healthy individuals referred to the laboratory for routine check-up, after matching for age and gender, was investigated. Data based on the type of variable were analyzed using independent t-tests, Mann-Whitney, Chi-square test, and Fisher's exact test using SPSS26 software at a significance level of 0.05.

In this study, 80 person participated, including 29 women (72.5%) and 11 men (27.5%) in each of two groups of patients with an average age of 52.17 ± 12.12 years and healthy people with an average age of 52.10 ± 12.23 years. The average serum level of vitamin D3 in the control group was significantly higher than the case group (P=0.006). There was no statistically significant relationship between the vitamin D3 serum level and different types of oral lichen planus, gender, duration of disease, and age.

Considering the significant lower mean serum level of vitamin D3 in people with oral lichen planus; vitamin D3 may be effective as a supplement in the healing process of patients' lesions.

Artificial intelligence (AI) technology is widely used in dentistry in addition to numerous other sectors that impact human life, including medicine. A dentist can use AI technology to analyze patient data, diagnostic processes, and management activities. This study was conducted in Iran to identify the dental applications of AI and prioritize them.

In the winter of 2022, this applied research was carried out in two stages using a mixed method. In the qualitative phase, 570 articles from 2011 to 2022 were identified in the databases of PubMed, Web of Science, Scopus and Google Scholar among the studies in the field of dentistry and related to artificial intelligence technology based on keywords and then the applications of artificial intelligence in dentistry were extracted. In the quantitative phase, the identified applications prioritized by a group of experts comprised 13 University faculty members with related research areas using the best-worst method (BWM).

The factors identified in the first stage of research were classified into six categories: implant and surgery, executive management, disease diagnosis, analysis of images, clinical prediction, and orthodontics. According to the experts’ opinion, it was determined that medical photo analysis had the highest coefficient of importance (0.252) followed by orthodontics (0.234), disease diagnosis (0.151), implantology and surgery (0.143), clinical forecasts (0.127), and executive management (0.093).

Dentists can use the capabilities of artificial intelligence in examining patients' teeth and diagnostic tests in dentistry based on the analysis of patient information. Information technology policymakers with the support and reinforcement of knowledge-based companies active in the field of artificial intelligence and joint investment in the field of medicine can be the basis for progress and the development of this technology in the country and the field of treatment.

Considering the problems associated with occupational stress and burnout caused by this stress, this study aimed to determine the academic burnout, dental environment stress, and their association among dental students in Isfahan.

This analytical cross-sectional study was conducted in 2020, applying a convenient sampling method. Data collected from undergraduate dental students from Isfahan University of Medical Sciences and Azad University of Isfahan using the validated Persian version of BCSQ-12-SS (Burnout Clinical Subtype Questionnaire) including 12 questions and DES (Dental Environment Stress) including 32 questions. Volunteer students filled in the online questionnaires using social media including WhatsApp and Telegram. Data were analyzed using SPSS26, U Mann-Whitney test, Kruskal-Wallis test, Spearman correlation coefficient, and a linear regression model (level of significance P<0.05).

Among 300 participants (response rate=64%), the mean age was 24.25±2.72, and 54.7% were women. The mean score of academic burnout was 2.61±0.66 of the maximum score of 5. Overload was the most effective dimension of academic burnout. The mean score of DES was 2.80±0.51 of the maximum score of 4. Clinical education was the most effective dimension of DES. A direct correlation was observed between the dental environment stress and academic burnout (P<0.001; r=0.33).

The academic burnout among dental students in Isfahan was moderate and dental environment stress was high. Considering the direct association between the stress and burnout, more efforts should be made to reduce dental environment stress especially in the field of clinical education.

The incisive canal cyst also known as nasopalatine duct cyst (NPDC) is the most common developmental non odontogenic cyst and it is usually asymptomatic with a well corticated round, ovoid or in some cases unique heart shaped radiolucent radiographic finding. Its accurate diagnosis from odontogenic cysts, odontogenic tumor, and benign non-odontogenic tumors using clinical and radiographic findings leads to eradication of pathologic condition with minimum residual defects and patient discomfort. In this case report, the clinical and radiographic findings of a 60-year-old female with the chief complaint of swelling was reviewed. There were typical histologic and radiographic findings related to nasopalatine duct cyst. The surgical management is explained. Follow up visit showed satisfactory healing and no dehiscence. It could be suggested that heart shaped radiographic finding in 3-D reconstructed image in the maxillary midline would be a good predictor for NPDC.

Dry socket is one of the most common post-tooth-extraction complications. The aim of this study was to investigate the relationship between some of the predisposing factors of dry socket and this complication in all maxillary and mandibular molars and evaluation of its incidence. Furthermore, the two jaws were compared.

In this descriptive-analytical cross-sectional study, 150 patients were examined in 2020 in the city of Zahedan. A questionnaire consisting of two sections was designed: In the first section age, gender, systemic disease, smoking status, contraceptive pill consumption, and antibiotic consumption were investigated. In the second section, data related to the difficulty of surgery based on the duration of surgery and the number of local anesthetic cartridges that were administered were collected. Then, the collected data were analyzed by Chi-square and Kruskal-Wallis tests.

The incidence of dry socket was 25.3%. The frequency of dry socket was significantly relevant to smoking, oral contraceptive consumption, difficulty of the surgery, and the number of local anesthetic cartridges that were administered (P≤0.05). Age, gender, controlled systemic disorder, and systemic antibiotic usage for two weeks prior to surgery revealed no significant associations with dry socket (P>0.05). Furthermore, the frequency of dry socket in maxillary and mandibular jaws had a significant difference according to smoking status, difficulty of surgery, and number of local anesthetics carpules (P≤0.05).

It is recommended to identify high-risk groups when performing extraction to consider pre-operative and post-operative measures in order to reduce postoperative complications.

Dentists are at risk of musculoskeletal disorders due to their job characteristics. The purpose of this study was to compare the posture and musculoskeletal disorders of dentists with high and low work experience.

This analytical cross-sectional study research was conducted on 76 dentists in Urmia city. Based on work experience, the samples were divided into two groups: less experienced (less than 15 years) and experienced (15 years and more). The variables of forward head, kyphosis, round shoulder, and musculoskeletal disorders were compared in two groups. Forward head and round shoulder variables were evaluated by photography, kyphosis variable by flexible ruler, and musculoskeletal disorders were evaluated by Nordic questionnaire. Data analysis was done using descriptive statistics and analytical statistics (Kolmogorov-Smirnov test, Leven test, independent t-test and Yeoman-Whitney test).

The independent t-test results showed that the angle of forward head, round shoulder, and kyphosis was higher in the high work-experience group than that of the low work-experience group (P=0.001). In comparing the prevalence of neck disorders, the results were significant such that the experienced group had more neck disorders (P=0.002). However, in examining the difference in the amount of disorders in other parts of the body, the difference between the two groups was not statistically significant (P>0.05).

Experienced dentists had a higher degree of forward head, round shoulder and kyphosis positions. Although, there are musculoskeletal disorders in both groups of dentists with low and high level of experience, neck disorders were more common in high-experienced dentists than that of low-experienced ones.

Mandibular third molar is the most common impacted tooth and craniofacial morphology and facial parameters can be appropriate predictors of impaction of this tooth. The aim of this study was to evaluate the relationship between Gonial angle, mandibular plane inclination, and ramus height with the impaction of mandibular third molar.

This retrospective descriptive-analytical study was performed by analysis of lateral cephalometric radiographic images of 172 patients in city of Zahedan in 2020. The status of eruption of mandibular third molars was determined by clinical examination and assistance of panoramic radiographic images and samples were categorized into four groups: fully erupted (1), partially impacted (2), impacted (3), partially developed (4). Then, the Gonial angle, mandibular plane, and ramus height were measured on lateral cephalometric images of each group and collected data were analyzed by Chi-square test and analysis of variance (ANOVA).

Among the patients, 68.02% were female and 31.97% were male. The difference between the mean values of Gonial angle of four groups was not statistically significant (P>0.05). In the fourth group, the mean value of mandibular plane inclination was significantly higher (29.74) and the mean value of the ramus height was significantly less (49.21 mm) than other groups.

According to the preformed analysis and obtained results, Gonial angle, mandibular plane, and ramus height were not accurate predictors for the impaction of mandibular third molar and further studies should be undertaken in this filed.

Endocrown is a type of monoblock restoration using the pulp chamber and remaining coronal tooth structure for retention. Advancements in adhesive techniques have breathed fresh spirit into endocrown. Nowadays, there are two approaches for endocrown: conventional approach and  biomimetic approach. This study aimed to review data on the steps and clinical and philosophical points of using these approaches to help dentists’ selection and performance.

The review was conducted by reviewing the articles available in PubMed, Scopus, and Google Scholar databases from 1995 to 2022. The keywords used were; Crown, Endodontically-treated teeth, Light-curing of dental adhesive, Onlay, and Post-Core.  

After removing duplicates, titles/abstracts were reviewed. Animal studies, studies without available full text or non-English language studies were excluded from the study. Then, the full texts of the remaining 59 articles were evaluated and 49 articles were eligible for the present study. The articles included clinical trials, in vitro, systematic reviews, and case reports.

Endocrown is a successful alternative to crown, especially in molar teeth. Regardless of the conventional or biomimetic approach, this treatment has a more favorable fracture pattern while preserving the remaining tooth tissue as much as possible.

One of the concerns of dentists is selecting a suitable brand of stainless steel crowns with maximum dimensional adaptation with primary teeth. The aim of this study was to compare the primary molar crown dimensions with that of two brands of stainless steel crowns (SSCs) in a sample of Iranian children.

 In this study, 130 eligible children between 3 and 12 years (66 boys, 64 girls) were selected. After recording the demographic information, the mesiodistal, buccolingual and occluso-gingival dimensions of first (D) and second (E) primary molars were measured on dental casts and compared with the dimensions of KTR (MeiMeiMinBenjing, Benjing, China) and Shinghung (Shinhungcompany, Seoul, South Korea) SSCs. Data were assessed using chi-square test and Pearson correlation coefficient. P<0.05 was considered statistically significant.

In this study, the most dimension matching of the teeth with that of SSCs were observed mesiodistally in upper D and lower D, buccolingualy in the upper D and lower D, and occluso-gingivaly in upper D and lower E. The most cases of mismatch in the mesiodistal dimensions of the teeth with that of SSCs were observed in the lower E and upper D. Also, the most cases of mismatch in the buccolingual dimension were found for upper E and lower E.

Both SSCs brands in this study showed significant dimensional adaptation with the primary teeth in Iranian children. The most dimensional adaptation was between KTR SSCs and maxillary primary molars, and between Shinhung SSCs and mandibular primary molars.

Pulp necrosis in immature teeth disrupts root development and makes the teeth susceptible to fracture. Regenerative endodontics is a relatively new modality of treatment where the necrotic pulp is replaced with newly formed healthy tissue which has normal functionality. Many clinical reports have demonstrated the potential of this strategy to induce root maturation and apical closure. However, clinical outcomes are patient-dependent and unpredictable. Developing predictable protocols can be achieved through the interplay of three basic elements of tissue engineering, namely, scaffolds, stem cells, and signaling molecules. Furthermore, the clinical success of this treatment is influenced by both the method of preparing the inner space of the root and the type of biomaterial utilized in the coronal part. In this review, we discuss recent advances in tissue engineering-based strategies for regeneration of the pulp/dentine complex along with their advantages and limitations.

Insufficient adhesion between fiber post and root canal is the main reason for the failure of the restoration and the fiber post surface treatment can imprive the bond strength. Additionally, there is disagreement about the ideal method of preparation to achieve the desired bond. The aim of this study was to compare the effect of two surface treatment methods on push-out bond strength of fiber posts to root canals.

In this study, 45 healthy incisor teeth underwent root canal treatment. After preparing the post space, they were divided into 3 groups of 15, based on the surface treatment methods of the fiber post. In the first group as control group, no surface treatment was done on the fiber post. In the second and third groups, sandblasting with Cojet sand particles and 810 nm diode laser were used for surface treatment, respectively. Then, fiber posts were placed in all root channels by a self-adhesive resin cement. Then, the roots were cut in such a way that from each, 3 pieces with a thickness of 1.5 mm were obtained. Finally, the push-out bond strengths were measured using a universal testing machine. Data were analyzed by ANOVA using SPSS software. The level of significance was considered at P<0.05.

The average bond strengths in three groups were as follows: control group, 2.877 ±1.430, sandblast group 6.318±3.444, and laser 4.224 ±1.890 MPa ± SD. The difference in the bond strength between the sandblast group and the control group was significant (P=0.001). However, the average of the bond strength of laser group was not significantly different from the control group. (P=0.03).

The findings of this study showed that unlike diode laser radiation, the use of Cojet sand particles for sandblasting the fiber post surfaces significanlty improved the bond strength.

Considering the prevalence of periodontal disease in Iranian adults and its impact on general health and the role of medical practitioners, the purpose of the present study was to determine physician’s knowledge and attitude towards periodontal health.

A cross-sectional study was conducted in Tehran in 2019 and after getting informed consent, a valid and reliable questionnaire was provided to medical practitioners in a continuing education course. Data were analyzed using the SPSS26 software.

In total 170 subjects (response rate=95%) responded. The mean scores of knowledge and attitude towards periodontal health were 4.1 (maximum score of 6) and 51.9 (maximum score of 65), respectively. Work experience (P=0.022) and period of time after graduation (P=0.007) had a positive and significant relationship with participants' knowledge. Also, gender (P=0.012), work experience (P=0.002), period after graduation (P=0.005) and practitioner’s workplace (P=0.001) were significantly associated with their attitudes. The results showed that women had a better attitude towards prevention of gum disease.

In the present study, medical practitioners’ knowledge was good towards description of healthy periodontium and the first sign of periodontal diseas. Also, their attitudes regarding the importance of oral and dental diseases and its impact on social activities were appropriate. The results of the present study showed more emphasis is needed on delivering relevant dental education in medical curriculum.

 Root canal treatment failures are often attributed to incomplete removal of bacteria, particularly Enterococcus faecalis. While, chlorhexidine and sodium hypochlorite serve as conventional treatments. herbal medicine has been today considered as an alternative to synthetic medicine due to its safety. Therefore, the aim of the present study was to compare the antibactrial effect of Scrophularia Striata extract with chlorhexidine and sodium hypochlorite on Enterococcus Faecalis in the tooth root canal.

 In this study, sixty extracted teeth were examined. Following the infection of dental canals with Enterococcus faecalis, materials were tested in 3 groups: 1) chlorhexidine 2% (18 teeth), 2) sodium hypochlorite 2.5% (18 teeth), and 3) Scrophularia striata (at the concentration obtained from MIC, 20%; 18 teeth). Additionally, the positive control and negative control were included (3 teeth in each group). Samples were then cultured on bile esculin agar. After 72 hours, black colonies were eaxamined. Chi-squared test was used to analyze the results.

 Enterococcus faecalis bacteria grew in 6, 8, and 17 out of the 18 teeth within the sodium hypochlorite, chlorhexidine, and Scrophularia striata extract groups, respectively. Consequently, the bactericidal effects for sodium hypochlorite, chlorhexidine, and Scrophularia striata extract were 66.6%, 55.5%, and 5.55%, respectively.

The antibacterial effect of the Scrophularia striata extract was significantly lower than chlorhexidine and sodium hypochlorite on Enterococcus faecalis in dental canals viewed as a suitable replacement to the already in use synthetic therapeutic irrigants.