جستجوی مقالات مرتبط با کلیدواژه "Dental" در نشریات گروه "پزشکی"

Some previous studies have suggested that laser irradiation improves the bond strength of composite to dentin. This study aimed to assess the effect of 810 and 970 nm diode laser on microtensile Bond Strength (µTBS) of universal adhesives to dentin. 

In this in vitro, experimental study, the occlusal third of 54 extracted third molars was cut, and they were randomly divided into 9 groups (n=18). In groups 1-3, Tetric N-Bond Universal (TNB), G-Premio Bond (GPB), and Single Bond Universal (SBU) adhesives were applied, respectively and the teeth were built-up by applying three 1-mm thick composite increments. The same was performed for groups 4-6 and 7-9 with the difference that they underwent 810 and 970 nm diode laser irradiation (0.8 W, 20 s), respectively, prior to light curing. All the teeth were then sectioned into 1×1 mm blocks and their µTBS was measured. Data were analyzed by two-way ANOVA and Tukey test.

The interaction effect of type of bonding agent and laser irradiation on µTBS was not significant (p=0.79). There was a statistical difference between the bond strength of the adhesive systems used (p=0.009).

Laser irradiation of universal adhesives applied by the etch and rinse (E&R) technique using 810 and 970 nm diode laser (0.8 W, 20 s) prior to their polymerization did not increase their µTBS to dentin.

This study aimed to compare the effects of requirement-based and test-based formative assessment methods on pre-clinical endodontic competence and performance of dental students.

This interventional field study was conducted on dental students of Shahid Beheshti Dental School in the first and second semesters of 2021 academic year (third-year students), taking practical basic endodontics 1. After receiving theoretical instructions and practical demonstrations, the students in both groups were asked to perform root canal therapy for extracted maxillary anterior and mandibular/maxillary canine teeth as part of their requirement. Their errors were assessed and recorded by two calibratedinstructors. Next, group 1 students performed root canal therapy for mandibular incisors and premolars as their requirement and returned the treated teeth on a specific date every 3 weeks. Group 2 students did not have a specific requirement and only participated in an examination which included endodontic treatment of the same group of teeth treated by group 1 students at the same designated dates. The treated teeth were assessed by instructors for errors. A final examination was held at the end of the semester for both groups. The two groups were compared by independent t-test, ANCOVA, Pearson Chi-square, and Mann-Whitney tests (alpha=0.05).

No significant difference was found between the two groups in access cavity preparation, root canal instrumentation, or obturation (P>0.05).

Requirement-based and test-based formative assessment methods had similar effects on pre-clinical endodontic competence and performance of dental students

Non-cognitive and personality variables, such as grit, have been shown to play an important role in medical science education. In order to facilitate studies in this field, it is necessary to have a reliable and valid instrument. The purpose of this study was to evaluate the factor structure and psychometric properties of the short Grit Scale (Grit-S) for Iranian dental students.

For this psychometric study, the short Grit-S was administered to a sample of dental students (n = 226) during the first semester of the academic year 2022-2023 at the School of Dentistry of Zanjan University of Medical Sciences. First, the questionnaire was translated, and then the psychometric properties of the Short Grit-S were evaluated. Descriptive statistics and Exploratory Factor Analysis (EFA) were performed using SPSS 26, while Confirmatory Factor Analysis (CFA) was conducted through AMOS 24.

The results of this study provide evidence for the validity and reliability of the Short Grit-S as a measure of grit among Iranian dental students. The internal consistency coefficient (Cronbach's alpha), split-half reliability, and test-retest were 0.80, 0.82, and 0.84, respectively. The Short Grit-S was found to be a valid and reliable instrument with good factorial validity, internal consistency, convergence, and criterion validity. The Short Grit-S was found to be useful for finding out how persistent Iranian dental students were in their efforts (Eigenvalue 3.53; variance explained 50.44) and how interested they were in learning (Eigenvalue 1.16; variance explained 16.55). The two-factor model with 7 items (item 2 was omitted) was found to be the best factor structure for the Persian version of the Short Grit-S.

In conclusion, the study found that the Persian version of the Short Grit-S with 7 items was a reliable and valid instrument for measuring grit among Iranian dental students.

“Complex problems require complex solutions” 1 and the population's oral health is a typical –and still unresolved- complex problem. There are some reasons why oral diseases are considered as a major and complex global public health problem. Over three billion people in the world suffer from these diseases 2, and their economic burden on individuals and societies is considerable 3, but the current treatment-oriented (rather than preventive) 4 high-technology approach has proved inefficient and has failed to address the underlying causes of these diseases as well as the existing inequalities in oral health. Even the most cited proposed models applied to understand the determinants of oral health are mostly linear and do not adequately consider the interaction of behavioral, psychological, sociological and structural factors. Thus, a fundamentally different approach is required for a ‘radical action’, i.e., a system change to reduce the burden of oral diseases. 5 In this commentary, we introduce “system thinking” (ST) as the required approach to address this hugely complex problem. We will start with a brief introduction to the definition and characteristics of ST. Then, we discuss how this approach might help policy makers to develop new and effective solutions for some specific problems in the dental public health domain. System thinking could be considered as an initiative or approach aimed at examining how things interact with each other within their respective contexts as a whole entity. 6 This approach has been emerged in the public health literature with impressive growth in the recent years and its implications in solving public health problems ranging from obesity to tobacco have been discussed. Public health interventions usually deal with complex issues that are multifactorial and multilevel. The recognition of such complexity has encouraged public health practitioners and researchers to experiment with systems sciences techniques to shift their focus from individual behavior changes to societal, environmental and policy interventions. 7 Thoughtful engagement with complexity, including capturing and understanding nonlinear cause and effect relationships, differing time scales, identification and management of unintended consequences, and transdisciplinary thinking can be regarded as the key strengths of systems approaches that could be adopted to solve public health problems. 8 Different theories and methods in ST have been designed to aid the analysis and address complex public health problems for which simple blueprint approaches have limited success. 9 Some tools are developed to facilitate reaching a common understanding of an issue, thus prompting further inquiry and action among a group of people. For example, “systems archetypes”, including causal loop diagrams (CLD), can help teams to understand the generic patterns of interaction that can be applicable to their “story”, rather than using the pre-existing templates. 10 CLD has the potential to promote our understanding of the broader political, institutional, and cultural contexts. It could be helpful in improving the currently accepted causality models in dentistry, which have commonly categorized determinants as structural, intermediate and proximal ones, with direct, linear and mostly unidirectional relations. 2 For example, understanding the current visible trend toward cosmetic dentistry in many high-income and even middle-income countries could be seen as a typical case that requires a system-thinking approach. Reduction of the trend to only a moral or financial issue is clearly insufficient. The interaction of a series of cultural, structural, economic and psychological causes could explain over-utilization or over-provision of aesthetic dental services. However, even when analyzing the commercial determinants of dental diseases, as an emerging approach in dental public health, its interactions seem to follow the same causality approach. Therefore, a system science approach might be helpful in identifying how unhealthy commodity industries market their products, gain control over policy, and legitimize their increasing presence in public health. Thus, identification of the connection circles for dental disease causes that would otherwise be missed in more individualized behavior approaches could be achieved by using such qualitative-quantitative methods as CLDs. One of the concerns of health planners has been the inquiry that whether interventions shown to be effective in a research setting would be simply replicated at the large scale or in the real world. The concept of “Effectiveness Decay” contributes the ‘effective coverage’ of an intervention to contextual and operational determinants. The process of using or utilizing an intervention begins with the questions asking whether patients access care and whether and how services are administered, received and adhered to. 11 Therefore, based on this concept, the real effectiveness of a community-based intervention might differ from the expected efficacy illustrated in small-scale research settings. For example, in the field of dental public health, based on a Cochrane systematic review of Fluoride Varnish (FV) application in ideal settings for clinical trials, it is suggested that this intervention can reduce the worsening of caries in the primary dentition with a prevention fraction of 37%. However, applying FV in wider public health programs has shown a modest and nonsignificant anti-caries effect. 12 The potential area for case loss in these interventions, or ‘node’, as a function of many concurrent forces between actors, context and structure of health systems might be discovered. 13 While effectiveness decay models highlight areas of deficiency requiring targeted attention, they do not reveal the underlying causes of such a decay. There are a number of other tools including network mapping, social network analyses and process mapping that are used to map out events or show how things are connected. Thus, it is possible to examine critical processes that are associated with the potential supply and demand-side determinants underlying the nodes indicated in the effectiveness decay models. 11 Application of ST in designing and evaluating the system-wide upstream policies seems to be another enormously important but overlooked issue. To design system-wide policies, the emphasis would be on some kind of multi-disciplinary and multi-stakeholder involvement. It is recommended that for a collective brainstorming on the possibly system-wide effects of the proposed upstream policies, the representative of each relevant sub-system (considering the relationships and dynamics among these sub-systems) is required. 14 The current unacceptable state of global oral health is rooted not only in external factors as competing disease priorities or scarcity of resources, but also in the inadequate coalescence among oral health actors and their disconnection with the wider global health mainstream. Therefore, to improve the populations' oral health, it is highly recommended that upstream policy interventions, such as legislation, regulation and fiscal change, focus more on the involvement of stakeholders from private and public sectors in oral health and other NCDs systems, industry, non-health sectors such as education councils, mass media, etc. We then need to focus on maximizing the synergy of efforts. Involvement of a wide range of stakeholders is crucial in conceptualizing the pathway of dynamic interactions in sub-systems or building blocks of the oral health system. Furthermore, system thinking can be beneficial for designing the methods to evaluate the implemented system-wide interventions. The emphasis in this approach is mainly upon incorporating plausibility designs such as “interrupted time-series”, which use mixed methods to provide estimates of adequacy, processes, contexts, effects and economic analyses of the interventions. They could complement and upgrade the traditional evaluation methods commonly used in health systems, i.e., probability designs such as randomized controlled trials with high internal validity but insufficient in evaluating system-wide interventions. Finally, it is worth mentioning that while the dental public health could benefit from system thinking approach to solve its special problems, the application of the such approach is emerging slowly in the oral health sector and mostly limited to the behavioral and psychological acculturation of dental habits such as tooth brushing. 15 The use of systems science within DPH is crucial to understanding and promoting good oral health for all, as well as to better understanding the complexity associated with the systems.

Dissatisfaction of parents with the appearance of conventional stainless-steel crowns (SSCs) has led the pedodontists to choose alternative esthetic restorations such as zirconia crowns.

In this report, a new approach for fabrication of direct composite crowns for primary molars was described using dual-cure core build-up composite material in five patients with one-year follow-up.

Direct composite crown appears to be a suitable esthetic restoration for pulpotomized primary molars in cooperative patients with acceptable oral hygiene.

In dentistry, acquiring knowledge, communication skills, and professional manual skills requires a favorable learning environment. This study aimed to investigate the association of decision-making styles and socioemotional skills in senior dental students (5th semester and higher) of Tehran Islamic Azad University.

This cross-sectional study evaluated 149 senior dental students. Their demographic information was collected, and they were asked to fill out the Melbourne Decision Making questionnaire (MDMQ), and Survey on Social and Emotional Skills (SSES) questionnaire to assess their social-emotional skills. The validity and reliability of the instruments were evaluated. Descriptive statistics and correlations were calculated between the scores of the MDMQ and SSES subscales, and P values < 0.05 were considered significant.   

A significant correlation was observed between SSES and MDMQ scores with a rho coefficient of 0.193 (P<0.018). Assertiveness presented positive correlations with MDMQ with a rho coefficient of 0.252 (P<0.002). A positive correlation was also found between tolerance skills and sociability skills with correlation coefficients of rho=0.145 and rho=0.141, respectively (P<0. 00). Significant correlations were observed between decision-making styles and the subscales of creativity (P<0.021) and trust skills (P<0.04), respectively.

A significant relationship was found between dental students' socioemotional skills and decision-making styles. Training that involves creativity and trust skills might be crucial for future decision-making by dental students.

Mobile phones have become a vital part of modern life, generating concerns about addiction among students. The present study aimed to assess smartphone usage and addiction among undergraduate dental students in Eluru, Andhra Pradesh. A cross-sectional study was conducted among 304 dental students using a pre-designed questionnaire based on the Smartphone Addiction Scale Short Version (SAS-SV). Data was analyzed using descriptive and inferential statistics. Out of 304 participants, most spent 3–4 hours on smartphones. Females showed slightly lower addiction scores than males. Addiction tendencies differed across different academic years, with second-year students scoring the highest. The study’s findings suggested that most dental students were addicted to smartphones. The study also revealed that having a smartphone was a crucial asset in their daily lives, and they preferred smartphones with advanced features.

 This in-vivo study evaluated the accuracy of full-arch digital impressions obtained through different intraoral scanning technologies regarding trueness and efficiency against the standard alginate impressions.

 Alginate impressions were taken from 50 subjects, and the resulting stone casts were scanned using the Trios 3Shape desktop scanner. In-vivo scans were conducted on each participant using three intraoral scanners: Medit, CEREC Primescan, and 3Shape Trios. The scanned files were superimposed onto two software platforms: the 3Shape Orthoanalyser and Geomagic software. This superimposition was performed against the reference model to calculate 3D and 2D deviations, enabling efficiency comparisons between digital and traditional workflows based on work time in minutes. Measurements and comparisons were made in three planes: transverse, sagittal, and vertical dimensions for all the models and stone casts. Statistical analysis employed SPSS 23, with the significance level set at P<0.05.

Significant deviations were observed between the three intraoral scanners and the alginate impression, with molar and premolar areas showing greater imprecision across dental arches. Compared to the alginate technique, Medit i500 tended to reduce the transverse dimension in the areas mentioned above, while CEREC exhibited higher precision. Molar and premolar areas emerged as the regions with the greatest discrepancies, both in excess and deficiency, compared to the alginate impression. This difference in dimensions was, however, statistically insignificant overall. 3Shape Trios exhibited the shortest scan times, indicating higher efficiency. Among the intraoral scanners, Medit recorded the longest scanning duration.

 Accepting the null hypothesis, the scans obtained using all three scanners were comparable with statistically insignificant differences in the measurements. The three scanners differed in the total scan time taken, with the Medit scanner requiring the longest scan time and the 3Shape TRIOS 3 scanner demonstrating the shortest scan duration.

 One of the key indicators of the effectiveness of a country's healthcare system is the delivery of accessible and impactful health services, particularly in the field of oral and dental healthcare. Among the barriers to the utilization of oral and dental healthcare services within healthcare systems, the most prominent obstacles are a lack of awareness and insufficient financial resources. The objective of this research is to investigate the factors that influence the extent to which individuals in Iran make use of dental insurance services.

 The research employed a linear probability model to evaluate how eight independent variables influence the utilization of dental insurance services. These variables included possession of supplementary dental insurance, age, parenthood, marital status, gender, level of education, DMFT index, and accessibility. The study encompassed data from 384 policyholders who participated across 20 dental clinics located in Tehran. Sampling was conducted using a stratified random sampling method, covering individuals with dental insurance from mid-2022 to mid-2023. The Kolmogorov-Smirnov test ensured data normality. One-sample examined hypotheses, while Pearson's Chi-Square tested relationships. The Gamma coefficient assessed relationship strength, and the Friedman test ranked factors influencing dental service utilization.

 Possessing supplementary dental insurance with an average rank of 5.2 is the most influential factor in the extent of utilization of dental services. The DMFT index, ranking on average at 2.5, is identified as the third factor (following accessibility to dental services as the second factor) in the utilization of dental services.

 Possessing insurance emerges as a crucial factor compared to the DMFT index when it comes to dental visits. In other words, Iranians with a DMFT index but lacking insurance coverage show a lower likelihood of seeking dental treatment. This observation holds true even in the more affluent northern areas of Tehran, contrasting with regions spanning from center to lower Tehran.

Fixed orthodontic retainers are pivotal in determining the success of treatment outcomes. However, the bonding materials utilized in their construction are not completely inert. These materials may release bisphenol A (BPA), a compound associated with various health risks. This study aimed to evaluate the cytotoxicity of potential bonding agents used in fixed orthodontic retainers.

In this experimental study, human gingival fibroblasts were cultured and subjected to various dental materials. These materials included acrylic resin (representing removable retainers), Transbond LR, and Enlight LV (which are common adhesives for fixed retainers), as well as Gradia Direct, Direct Flo, and Herculite XRV (commonly used in restorative composites). A control group was also exposed to normal saline. Discs measuring 0.5×1×1 mm were prepared from these materials. The viability of the fibroblasts was assessed using the MTT assay, and a statistical analysis (one-way analysis of variance) was conducted to compare the groups at a significance level of 0.05.

The results of statistical analysis indicated no significant difference between the groups in terms of cytotoxicity for human gingival fibroblasts (p= 0.71).

 None of the tested materials negatively impacted the viability of human gingival fibroblasts. These results provide valuable clinical insights, reassuring orthodontic practitioners about the safety profile of these commonly used materials in the context of fixed orthodontic retention and restorative procedures.

Positive attitude of dentists towards the professional ethical principles can improve the quality of provided services and minimize occupational stress. This study aimed to assess the attitude and professionalism in education of dental residents at the School of Dentistry of Islamic Azad University, Tehran.

This descriptive cross-sectional study was conducted on all dental residents attending the School of Dentistry of Islamic Azad University in Tehran in 2022. Data were collected using the American Board of Internal Medicine (ABIM) professionalism questionnaire, which was translated to Persian by Aramesh, and its validity and reliability were confirmed. This questionnaire includes two parts of (I) demographic information, and (II) questions regarding the perception of professionalism at work (totally 17 questions) in four main domains of excellence, honor/integrity, altruism/respect, and empathy. Data were collected through face-to-face interviews and analyzed by one-way ANOVA and regression test. 

Of 57 dental residents, 26.3% were males and 73.7% were females. The mean total score of professionalism was found to be 114.96±23.45 out of 153, and the overall percentage of professionalism was calculated to be 75.13%±15.33% out of 100%. The percentage of professionalism score in the third-year and higher residents was 8% higher than that in second-year residents (P=0.052). The mean percentage of professionalism score was not significantly correlated with the field of specialty, gender, age, participation in related courses, or grade point average (GPA) (P>0.05).

It appears that attitude and professionalism of dental residents of School of Dentistry of Islamic Azad University of Tehran in 2022 were optimal. The honor/integrity domain acquired the highest, and the altruism/respect domain gained the lowest score.

In dental education, understanding optimal assessment methods and factors like stress and confidence is essential. This research assessed second-year dental students' performance in fixed prosthodontics using multiple-choice questions (MCQs) and pre-clinical practical exams, examining impacts of gender, stress, and confidence.

Using a quasi-experimental design, 495 students from a single faculty underwent assessment. Selected via convenience sampling, they were exposed to MCQs and practical exams in fixed prosthodontics. An expert-reviewed questionnaire gauged their stress and confidence. Data was analyzed using descriptive statistics, t-tests, and Pearson's correlation. Additionally, a balanced sub-set of 176 students (88 males and 88 females) was chosen for gender-based analysis.

Findings indicate statistical parity between MCQ and practical exam performances (p>0.001). Females slightly outperformed in MCQs, while males excelled in practicals, without reaching statistical significance (p>0.05). Stress correlated with practical exam outcomes (r=0.34, p=0.001), and confidence with MCQ scores (r=0.41, p<0.0001).

The research underscores near-equivalence of MCQs and practical exams for student assessments in fixed prosthodontics. Recognizing the roles of stress and confidence in assessments offers insights for balanced evaluations. Dental faculties should integrate these findings, and future work should pivot towards tool validations for enriched learning.

Porcelain laminate veneers (PLV) offer a conservative aesthetic solution for interdental space closure. However, space is typically not distributed symmetrically, and the mesiodistal width of the restored teeth may increase unless multiple teeth are prepared for conventional PLV to maintain appropriate individual tooth proportion. Ceramic fragments can be suggested to close the space without modifying tooth size and dental proportion. This article presents two cases where interdental gaps were closed using lingually placed porcelain laminate (LPPL). All stages of the restorative procedures, including treatment planning, temporization, tooth preparation, and cementation of these delicate restorations, are detailed. Based on the results of these clinical reports, we regard the use of LPPL as a successful treatment option in selected cases, as evidenced by 2- and 6-year follow-ups. The Modified United State Public Health Criteria is reported.

Porcelain chipping and delamination are among the shortcomings of all-ceramic restorations. This study aimed to assess the effect of laser irradiation and sandblasting on shear bond strength (SBS) of zirconia to veneering porcelain.

In this in vitro, experimental study, 60 zirconia blocks were randomly divided into three groups (n=20) for surface treatment with Er:YAG laser, sandblasting, and no surface treatment (control). Each group was randomly divided into two subgroups (n=10) for porcelain application by the layering or the pressing technique. The surface roughness, SBS, and failure mode were determined and analyzed using two-way ANOVA, Tukey’s HSD test, Chi-square test, and Pearson’s correlation test (alpha=0.05).

The mean SBS was 8.16±3.66 MPa, 9.32±2.7 MPa, and 11.85±3.06 MPa in the control, laser, and sandblasting groups, respectively. The SBS was significantly different among the three groups (P=0.002). The failure mode of the three groups was not significantly different (P>0.05). The sandblasted group showed significantly higher surface roughness than the control and laser groups (P<0.001).

Sandblasting yielded higher SBS particularly when the porcelain was applied by the layering technique. Although laser irradiation increased the SBS, the difference with the control group was not statistically significant.

Proper planning of orthodontic services at a communal level requires a clear understanding of the correct approach to providing orthodontic treatments to different population groups. Thus, this study aimed to evaluate the level of awareness of orthodontic treatments among general dentists and dental students in their last two years of study in Isfahan city.

In this analytical descriptive and study, 75 dental students in their last two years of  study at faculty of Dentistry, Isfahan Azad University ,and 75 general dentists in Isfahan City were randomly selected. Participants were given a questionnaire consisting of two parts: the first part was related to background information, and the second part contained 25 questions aimed at determining the level of awareness. Data was analyzed using Chi-square, Mann-Whitney, and Spearman correlation tests (α= 0.05). 

The results showed no significant difference in the mean scores between dental students, and general dentists (P=0.301). However, women demonstrated a significantly higher level of awareness compared to men (P=0.002).The level of awareness did not differ significantly with age (P=0.124) or work experience of dentists (P=0.848).  Furthermore, here was no significant difference in the mean scores of 6ths and 5th year students. (P=0.91).

The level of awareness of general dentists and dental students in their last two years of study was medium with women demonstrating a higher level of awareness. The level of awareness was not influenced by age, work experience, and year of entering the university.