Mechanisms underlying sex bias in oral immune-mediated conditions, an insight.

The predilection for women in systemic autoimmune diseases is well established. However, this sex bias in oral autoimmune diseases has been classically reported from an epidemiological perspective without any elaborate attempts to unveil the underlying mechanisms. The unique nature of the oral environment is likely to impose a combination of systemic and local factors that ultimately result in the sex bias in autoimmune diseases of the oral cavity. Variations of immune responses, target organ vulnerability, endocrine and genetic factors, sex chromosomes and modes of parental inheritance are potential systemic factors, while the oral microbiome, oral tolerance, saliva, and oral epithelial stem cells may account for local contributing factors. This review will discuss the preponderance of women in oral immune-mediated diseases, the potential systemic and local mechanisms underlying this predominance and highlight the crucial need for further research in this area.

Prevalence of Burnout among Dental Students during COVID-19 Lockdown in UAE.

AIM: To estimate the prevalence of burnout among dental students in two major universities in the United Arab Emirates during the coronavirus disease-2019 (COVID-19) lockdown. MATERIALS AND METHODS: In this cross-sectional observational study, the burnout clinical subtype questionnaire (BCSQ-12-SS) (English version) was used. It consists of 12 questions covering domains of overload (4 questions), lack of development (4 questions), and neglect (4 questions). The questionnaire was sent to 500 dental students from the University of Sharjah (UOS) and Ajman University of Science and Technology (AUST). The association between burnout and sociodemographic variables was also investigated. RESULTS: The majority of responders were females (74%). Socio-demographic and study characteristics of dental students from both universities were not remarkably different. However, the responses to the BCSQ-12-SS questions were not very different. In this study, there was no significant association between burnout and demographic variables, such as age, gender, relationships, distance from family, residency, year of study, studying hours, and number of failed subjects. However, there was a significant association between burnout and receiving a scholarship and family support. CONCLUSION: Identifying individuals at risk for burnout may provide a potential intervention strategy and counseling to assist in dental student development, as it has good psychometric properties. CLINICAL SIGNIFICANCE: Burnout among dental students could develop into anxiety and depressive disorders. Early identification and prevention will protect the psychological well-being of dentists. How to cite this article: Al-Rawi NH, Yacoub A, Zaouali A, et al. Prevalence of Burnout among Dental Students during COVID-19 Lockdown in UAE. J Contemp Dent Pract 2021;22(5):538-544.

Oral health awareness, attitude towards dental treatment, fear of infection and economic impact during COVID-19 pandemic in the Middle East.

OBJECTIVES: To assess the impact of COVID-19 on oral hygiene (OH) awareness, attitude towards dental treatment, fear of infection and economic impact in the Middle East. METHODS: This survey was performed by online distribution of questionnaires in three countries in the Middle East (Jordan, Iraq and Egypt). The questionnaire consisted of five sections: the first section was aimed at collecting demographic data and the rest sections used to assess OH awareness, attitude towards dental treatment, degree of fear and economic impact of COVID-19. The answers were either multiple choice, closed-end (Yes or No) or 5-point Likert scale for the last four sections. RESULTS: A total of 3782 respondents completed the questionnaire. Overall, OH awareness was low (mean ±SD; 1.84 ± 1.03), while attitude towards dental treatment (5.04 ± 1.68) and economic impact (11.29 ± 4.37) were moderately affected. In addition, fear of infection showed moderately high level (14.04 ± 4.11). All subgroups of the demographic variables showed significant differences among them in relation to OH awareness and attitude towards dental treatment. The regression model suggested country, gender, age, education level, income level and fear as predictors for OH awareness (R2 0.036) and attitude towards dental care (R2 0.141). CONCLUSIONS: The pandemic negatively impacted the level of OH awareness. However, the attitude towards dental treatment was moderately affected. Increasing public fear and compromised economy influenced OH awareness and the attitude towards dental treatment.

Vertebral Malalignment among Male Dentists with Work-related Musculoskeletal Pain in the United Arab Emirates.

AIM: Musculoskeletal pain (MSP) is a highly prevalent and debilitating disorder among dentists, often leading to early retirement. Poor ergonomics in the dental practice not only causes MSP, but can also lead to postural deviations as a result of an imbalance in muscle function. The aim of this study was to observe the relationship between MSP and vertebral deviations among male dentists in the United Arab Emirates (UAE). MATERIALS AND METHODS: A total of 60 male dentists participated in this cross-sectional study. Standardized Nordic questionnaire (SNQ) was used to record MSP and PostureScreen Mobile® (PSM) application was used to observe postural deviations in the vertebral regions, including the neck, shoulders, upper back, lower back, and hips. RESULTS: About 83% of participants were suffering from MSP, with the lower back as the most commonly reported region (29%). The pain characteristics reported were chronicity (63%) and dullness (72%). As for postural deviations, the most common site recorded was the neck region (72%). The correlation between the regions of deviation and the regions of pain showed that the shoulder region was more significant than other regions. CONCLUSION: Musculoskeletal pain and vertebral malalignment are common among practicing dentists, probably because of bad postural habits and lack of awareness. Preventive strategies to minimize the risk of developing these health problems are highly recommended. CLINICAL SIGNIFICANCE: Work-related MSP (WRMSP) is a significant health problem among dentists and may be linked to the later development of vertebral deviations. Posture screen analysis is a quick, yet objective postural and movement screening tool in which findings can quickly be rendered to prospective dentists, so that custom postural and functional exercises may be correctly practiced.

Work-related Musculoskeletal Pain among Different Dental Specialists in United Arab Emirates.

INTRODUCTION: Dentists are at a very high risk of developing work-related musculoskeletal pain. The present study aimed at studying the prevalence of musculoskeletal pain among different dental specialists in the United Arab Emirates (UAE), and correlating the region of pain with the type of clinical work done by the specialists. MATERIALS AND METHODS: A sample of more than 100 dentists was chosen randomly from different emirates in UAE. An interview questionnaire was administered regarding the number of years of experience and the presence, region, duration, and type of musculoskeletal pain they experienced. RESULTS: Musculoskeletal pain is experienced by 83.3% of periodontists, 80% of conservative dentists, 77.8% of endodon-tists, 72.7% of orthodontists, 70% of oral surgeons, 63.6% of prosthodontists, 63% of general dental practitioners, and 50% of pedodontists. The results have also indicated that the region of experienced musculoskeletal pain does vary according to the specialty. From those dentists who experience work-related musculoskeletal pain, 80% of conservative dentists experience pain in neck and shoulders, 66.7% of periodontists, and 54.5% of orthodontists experience pain in the lower back region. More than 50% of endodontists experience pain in the neck and shoulders regions, and 39% of general dental practitioners who experience pain in the neck region. CONCLUSION: Preventive measures need to be taken to decrease the risk of dentists and dental specialists developing work-related musculoskeletal pain. CLINICAL SIGNIFICANCE: The prevalence and distribution of musculoskeletal disorders (MSDs) among registered general dental practitioners and dental specialists in UAE was not clearly documented. The study results indicated that the region that experienced musculoskeletal pain does vary according to the specialty.

Tunable theranostics: innovative strategies in combating oral cancer.

Objective: This study aims to assess and compare the potential of advanced nano/micro delivery systems, including quantum dots, carbon nanotubes, magnetic nanoparticles, dendrimers, and microneedles, as theranostic platforms for oral cancer. Furthermore, we seek to evaluate their respective advantages and disadvantages over the past decade. Materials and Methods: A comprehensive literature search was performed using Google Scholar and PubMed, with a focus on articles published between 2013 and 2023. Search queries included the specific advanced delivery system as the primary term, followed by oral cancer as the secondary term (e.g., "quantum dots AND oral cancer," etc.). Results: The advanced delivery platforms exhibited notable diagnostic and therapeutic advantages when compared to conventional techniques or control groups. These benefits encompassed improved tumor detection and visualization, enhanced precision in targeting tumors with reduced harm to neighboring tissues, and improved drug solubility and distribution, leading to enhanced drug absorption and tumor uptake. Conclusion: The findings suggest that advanced nano/micro delivery platforms hold promise for addressing numerous challenges associated with chemotherapy. By enabling precise targeting of cancerous cells, these platforms have the potential to mitigate adverse effects on surrounding healthy tissues, thus encouraging the development of innovative diagnostic and therapeutic strategies for oral cancer.

Histological evaluation of bone healing using organic bovine bone in combination with platelet-rich plasma (an experimental study on rabbits).

OBJECTIVES: This study was carried out to histologically assess the effect of bone grafting materials extracted from bovine origin on the bone healing process either alone or when mixed with autologous platelet-rich plasma which could be used in many procedures of oral and maxillofacial bone and implant reconstructive surgery. MATERIALS AND METHODS: Sixteen rabbits were used; three intrabony defects in the femur bone of each rabbit were created, one left unfilled for normal healing process and served as control, the second filled with xenogenic graft (Gen-Ox-lyophilized bovine bone organic matrix), and the third filled with (Gen-Ox-lyophilized bovine bone organic matrix) mixed with autologous platelet-rich plasma. Histological examination of the sections was performed after staining with H&E and Van Geison stains. The histomorphometric analysis including counting of bone cells (osteoblasts, osteocytes, and osteoclasts) with performance of osteon diameter and lamellar thickness at the end of the fourth week postoperatively was obtained. RESULTS: It has been shown that with the use of autologous platelet-rich plasma in combination with the xenogenic bone graft prepared from bovine origin, new bone formation and neovascularization were enhanced significantly when compared with xenogenic graft alone. CONCLUSION: The addition of PRP to xenogenic bone substitute in small bone defects of the rabbit femur showed a histomorphometric increase in bone formation (at the fourth week of healing). CLINICAL RELEVANCE: Platelet concentrate might be used to accelerate the osseointegration of enosseous dental implants.

Prediction of Lymphovascular and Perineural Invasion of Oral Squamous Cell Carcinoma by Combined Expression of p63 and Cyclin D1.

OBJECTIVES: The aim of this study was to determine the value of immune expression of p63 and cyclin D1 in the prediction of lymphovascular invasion (LVI) and perineural invasion (PNI) in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Clinical and histopathologic features of 65 subjects with histologically confirmed OSCC were collected. Tissue microarray blocks representing all subjects were prepared for the immunohistochemical quantification of the nuclear expression of p63 and cyclin D1 using immune ratio plugin of image J software. Image analysis was performed by two independent pathologists. Independent samples t-test, analysis of variance, and receiver operating characteristic curve tests were used for statistical analysis. The level of significance was set at p≤ 0.05. RESULTS: The optimum cutoff value for the prediction of LVI for p63 and cyclin D1 was found to be 100 and 93.2, respectively, while the optimum cutoff value for the prediction of PNI for p63 and cyclin D1 was found to be 95.9 and 94, respectively. p63 and cyclin D1 expression correlated with several clinicopathologic features of the studied population. p63 expression was a significant predictor of moderate/poorly differentiated OSCC compared with well-differentiated OSCC. A parallel combination of positive p63 and cyclin D1 increased the specificity of predicting LVI from 89.1% and 67.4% for either p63 or cyclin D1, respectively, to 93.5% with a positive predictive value of 92.5%. Similarly, the parallel combination of the two markers raised the specificity of predicting PNI from 70% and 77.5% for either p63 or cyclin D1, respectively, to 90% with a positive predictive value of 86.3%. CONCLUSION: Combined overexpression of nuclear markers p63 and cyclin D1 can be considered as a valuable independent predictor of LVI and PNI, and hence tumor progression, in OSCC.

The impact of reflex-based recreational activities and preclinical training on psychomotor skills in an educational dental environment.

BACKGROUND: Participating in recreational activities from a young age may have the potential enhance psychomotor skills early on, and conversely, low levels of participation in these activities may predict slower development of preclinical hand skills. PURPOSE: This study aims to evaluate the eye-hand coordination benefits of leisure and reflex-based activities to those of typical instructional techniques among dental students. DATA SOURCES: The databases used were PubMed, EBSCOhost, and Scopus. STUDY SELECTION: Ten articles were selected from a total of 1135 articles found across three databases. DATA EXTRACTION: The articles were screened by four investigators through a series of steps in accordance to inclusion and exclusion criteria and rid of any duplicates. DATA SYNTHESIS: The majority of the 10 featured articles were conducted in the United States. All of the research included was cohort observational studies. This systematic review includes a total of 1975 participants from the publications selected for this purpose. RESULTS: Manual dexterity may be taught and improved by practice, and tests designed to measure it should be used primarily to pinpoint which students would benefit most from individualized, close supervision during their education. CONCLUSION: Researchers found that reflex-based activities helped students develop better hand-eye coordination in a classroom setting. However, more precise dental-related tests and questionnaires can always be developed through further study; doing so would yield a wealth of information that would be immensely useful to the dental sector.

MicroRNA expression in apical periodontitis and pulpal inflammation: a systematic review.

Background: The aim of this systematic review is to determine microRNAs (miRs) that are differently expressed between diseased pulpal and periapical tissues. Design: This systematic review used PubMed, Scopus, EBSCO, ProQuest, Cochrane database as well as manual searching to extract studies from January 2012 up to February 2022. Results: A total of 12 studies met the eligibility criteria were included. All selected studies were of case-control type. Twenty-four miRNAs associated with apical periodontitis, 11 were found to be upregulatedand 13 were downregulated. Four out of the 44 miRs associated with pulpal inflammation were upregulated, whereas forty were downregulated. Six miRs, namely hsa-miR-181b, hsa-miR-181c,hsa-miR-455-3p,hsa-miR-128-3p, hsa-miR199a-5p, and hsa-miR-95, exhibited considerable downregulation in both periapical and pulp tissues. Conclusion: MiRs have been investigated for their role in pulpal and periapical biology and may be utilised in diagnostic and therapeutic purposes. Further investigations are required to determine why certain irreversible pulpitis situations progress to apical periodontitis and others do not, based on the various miR expressions. Moreover, clinical and laboratory trials are needed to support this theory.

Differential Expression Profile of Salivary oncomiRNAs among Smokeless Tobacco Users.

OBJECTIVE: The aim of this study was to evaluate the expression of selected salivary oncomiRNAs among smokeless tobacco users and nonsmokers. MATERIALS AND METHODS: Twenty-five subjects with chronic smokeless tobacco habit (> 1 year) and 25 nonsmokers were selected for this study. MicroRNA was extracted from saliva samples using the miRNeasy Kit (Qiagen, Hilden, Germany). The forward primers used in the reactions include hsa-miR-21-5p, hsa-miR-146a-3p, hsa-miR-155-3p, and hsa-miR-199a-3p. Relative expression of miRNAs was calculated using the 2-ΔΔCt method. Fold change is calculated by raising 2 to the power of the negative ΔΔCT value. STATISTICAL ANALYSIS: Statistical analysis was carried out using GraphPad Prism 5 software. A p-value less than 0.05 was considered statistically significant. RESULTS: The four tested miRNAs were found overexpressed in saliva of subjects with smokeless tobacco habit when compared with saliva from nontobacco users. miR-21 expression was 3.74 ± 2.26 folds higher among subjects with smokeless tobacco habit compared to nontobacco users (p < 0.01). The expression for miR-146a (5.56 ± 8.3 folds; p < 0.05), miR-155 (8.06 ± 23.4 folds; p < 0.0001) and miR-199a (14.39 ± 30.3 folds; p < 0.05) was significantly higher among subjects with smokeless tobacco habit. CONCLUSION: Smokeless tobacco leads to salivary overexpression of the miRs 21, 146a, 155, and 199a. Monitoring the levels of these four oncomiRs may provide insight about the future development of oral squamous cell carcinoma, especially in patients with smokeless tobacco habits.

Anatomical landscape of oral squamous cell carcinoma: A single cancer center study in UAE.

Objectives: This study aimed to present demographic and clinicopathological aspects of OSCC identified in Pathology service in the UAE over a 13-year period and compare these findings to a cohort of 523 cases of Head and neck squamous cell carcinoma using the Cancer Genome Atlas's cBioPortal database (http://cbioportal.org). Material and methods: Histological examination of all hematoxylin and eosin-stained slides and assessment of all demographic and clinical information from laboratory records were performed on all OSCC diagnosed between 2005 and 2018. Results: Males made up 71.4% of the sample of 231 OSCCs that were evaluated. The patients' average age was 55.38 years. The two most prevalent afflicted sites were the anterior two-thirds of the tongue (57.6%) and the cheek (28.1%). The most prevalent site among smokers were the floor of mouth, cheek, and jaw bones. There was a link between tumor size and numerous anatomical subsites that was shown to be highly significant. OSCC in the FOM was associated with a 25% mortality rate. Patients with OSCC of the anterior tongue and cheek had the best prognosis, with only 15.7% and 15.3% of patients dying during follow-up. Conclusion: The present investigation found a correlation between the diverse clinicopathological characteristics of the various anatomical subsites in OSCC. Different anatomical subsites also displayed varying degrees of gene mutation.

Morphometric analysis of odontoid process among Arab population: a retrospective cone beam CT study.

Objective: This study aims to evaluate the feasibility of using cone beam computed tomography (CBCT) scans to assess the odontoid process diameter in the Arab population and to determine whether one or two cortical screws can be used for treating odontoid fractures. Methods: The odontoid process of 142 individuals aged 12-75 years, including 72 males (mean age: 35.5) and 70 females (mean age: 36.2), were analyzed using CBCT scans. The sagittal and coronal CBCT views were used to evaluate the antero-posterior (AP) and transverse diameters of the odontoid process. Results: Males had substantially bigger transverse and AP diameters of the odontoid process than females (p < 0.05 & P < 0.01 respectively). Among the sample, 97 individuals (67.4%) had external transverse diameter (METD) of less than 9 mm which is slightly bigger than that of Indians and 48 individuals (31.83%) had enough room for two 3.5 mm or two 2.7 mm screws as their METD was more than 9 mm like that of Greek and Turkish. Age had no significant impact on the morphometric measurements of the odontoid process. Conclusion: More than sixty percent of the sample had METDs of less than 9 millimeters, indicating that a single 4.5-mm Herbert screw may be suggested for fixing fractured odontoid processes in the Arab population.

Titanium dioxide dental implants surfaces related oxidative stress in bone remodeling: a systematic review.

Background: Titanium dioxide dental implants have a controversial effect on reactive oxygen species (ROS) production. ROS is necessary for cellular signal transmission and proper metabolism, but also has the ability to cause cell death as well as DNA, RNA, and proteins damage by excessive oxidative stress. This study aimed to systematically review the effect of titanium dioxide dental implant-induced oxidative stress and its role on the osteogenesis-angiogenesis coupling in bone remodeling. Methods: This systematic review was performed conforming to preferred reporting items for systematic review and meta-analysis (PRISMA) model. Four different databases (PubMed, Science Direct, Scopus and Medline databases) as well as manual searching were adopted. Relevant studies from January 2000 till September 2021 were retrieved. Critical Appraisal Skills Programme (CASP) was used to assess the quality of the selected studies. Results: Out of 755 articles, only 14 which met the eligibility criteria were included. Six studies found that titanium dioxide nanotube (TNT) reduced oxidative stress and promoted osteoblastic activity through its effect on Wnt, mitogen-activated protein kinase (MAPK) and forkhead box protein O1 (FoxO1) signaling pathways. On the other hand, three studies confirmed that titanium dioxide nanoparticles (TiO2NPs) induce oxidative stress, reduce ostegenesis and impair antioxidant defense system as a significant negative correlation was found between decreased SIR3 protein level and increased superoxide (O2 •-). Moreover, five studies proved that titanium implant alloy enhances the generation of ROS and induces cytotoxicity of osteoblast cells via its effect on NOX pathway. Conclusion: TiO2NPs stimulate a wide array of oxidative stress related pathways. Scientific evidence are in favor to support the use of TiO2 nanotube-coated titanium implants to reduce oxidative stress and promote osteogenesis in bone remodeling. To validate the cellular and molecular cross talk in bone remodeling of the present review, well-controlled clinical trials with a large sample size are required.

Postoperative care in ICU versus non-ICU after head and neck free-flap surgery: a systematic review and meta-analysis.

OBJECTIVE: Admission to the intensive care unit (ICU) has long been considered as routine by most head and neck surgeons after microvascular free-flap transfer. This study aimed to answer the question 'Is there a difference in the flap survival and postoperative complications rates between admission to intensive care unit (ICU) versus Non-ICU following microvascular head and neck reconstructive surgery?'. DESIGN: Systematic review, and meta-analysis. METHODS: The PubMed, Embase, Scopus and Cochrane Library electronic databases were systematically searched (till April 2021) to identify the relevant studies. Studies that compared postoperative nursing of patients who underwent microvascular head and neck reconstructive surgery in ICU and non-ICU were included. The outcome variables were flap failure and length of hospital stay (LOS) and other complications. Weighted OR or mean differences with 95% CIs were calculated. RESULTS: Eight studies involving a total of 2349 patients were included. No statistically significant differences were observed between ICU and non-ICU admitted patients regarding flap survival reported (fixed, risk ratio, 1.46; 95% CI 0.80 to 2.69, p=0.231, I2=0%), reoperation, readmission, respiratory failure, delirium and mortality (p>0.05). A significant increase in the postoperative pneumonia (p=0.018) and sepsis (p=0.033) was observed in patients admitted to ICU compared with non-ICU setting. CONCLUSION: This meta-analysis showed that an immediate postoperative nursing in the ICU after head and neck microvascular reconstructive surgery did not reduce the incidence of flap failure or complications rate. Limiting the routine ICU admission to the carefully selected patients may result in a reduction in the incidence of postoperative pneumonia, sepsis, LOS and total hospital charge.

Analysis of inferior nasal turbinate volume in subjects with nasal septum deviation: a retrospective cone beam tomography study.

Background: The association of the linear dimensions of the inferior turbinate hypertrophy with nasal septal deviation has been studied recently. However, the volumetric dimensions provide a more accurate status of the turbinate hypertrophy compared to linear measurements. The aim of this study was to analyze the association of inferior nasal turbinate volume with the degree of nasal septal deviation (NSD). Methods: A retrospective evaluation of the cone beam computed tomography (CBCT) scans of 412 patients was carried out to obtain 150 scans which were included in the study. The scans were categorized into three groups. Group 1 comprised of 50 scans of patients with no inferior turbinate hypertrophy (ITH) and no nasal septal deviation. Group 2 comprised of 50 scans of patients with ITH and no NSD; whereas Group 3 included 50 scans of patients with ITH and NSD. The total turbinate volume of inferior turbinates (bilateral) were determined by using Vesalius 3D software (PS-Medtech, Amsterdam, Netherlands). Results: The intraclass correlation coefficient (ICC) between the volumetric estimations performed by the two radiologists was 0.82. There were no significant age and gender related changes in the total turbinate volume. Patients in Group 3 had significantly higher (p = 0.001) total turbinate volume compared to Group 2 and Group 1. There was a positive and significant correlation (r = 0.52, p = 0.002) between the degree of septal deviation and total turbinate volume. When the total turbinate volume of the patients with different types of septal deviation was compared in Group 3, a statistically significant difference (p = 0.001) was observed. Regression analysis revealed that the septal deviation angle (SDA) (p = 0.001) had a relationship with total turbinate volume. From the results of the study we can conclude that the total turbinate volume is higher in patients with nasal septal deviation. It can also be concluded that the septal deviation angle has a positive correlation with total turbinate volume. The data obtained from the study can be useful in post-surgical follow up and evaluation of patients with nasal septal deviation and hypertrophied inferior nasal turbinate.

Prevalence of Anosmia or Ageusia in Patients With COVID-19 Among United Arab Emirates Population.

OBJECTIVE: The aim of this research was to determine the relationship and prevalence of taste and smell dysfunction in patients with COVID-19 in the United Arab Emirates (UAE) population. METHODS: Enrolled participants were interviewed online via a phone call after obtaining their informed consent. Quantification of smell, taste, and other sensations before, during, and after COVID-19 infection was correlated with the severity of COVID-19 symptoms. RESULTS: A total of 500 patients with (mild-severe) COVID-19 completed the survey. A total of 26.4% were asymptomatic, and 21.4% were classified as paucisymptomatic with less severe symptoms. Almost equal proportions of the studied population experienced extreme taste sensation reductions (43%) and loss of smell sensation (44%). Statistically significant drastic decreases in smell and taste senses were seen among younger individuals. The magnitude of reduction in both sense changes increased steeply from the asymptomatic group to the paucisymptomatic group to the symptomatic group. CONCLUSIONS: Sudden anosmia or ageusia need to be recognised for early detection of COVID-19 infection to identify otherwise hidden carriers, thus favoring an early isolation strategy that will restrict the spread of the disease.

Comparative Analysis of Manual Dexterity of Dental Students at Ajman University following One Academic Year of Preclinical Training Sessions: A Longitudinal Cohort Study.

OBJECTIVES: Dental students must complete two stages of training, namely, preclinical training on phantom head models and clinical training on actual patients to acquire the practical skills required by their Bachelor of Dental Surgery program.Our objectives are to evaluate the level of improvement of the manual skills obtained by third-year dental students after one full academic year of preclinical training courses using dexterity tests under direct and indirect vision and to compare the improvement among male and female dental students under the same conditions. MATERIALS AND METHODS: A total of 72 preclinical students participated in our cohort trial, each of whom was assigned a random identification number that was only known to the researchers. After the beginning of the academic year, the experiment was performed under identical conditions for both the O'Connor Tweezer Dexterity Test and the Purdue Pegboard Test. The examinations were conducted at two distinct times: T0 before phantom laboratory training (the beginning of preclinical sessions) and T1 after phantom laboratory training (9 months after T0). STATISTICAL ANALYSIS: Signed-rank test of Wilcoxon over two separate periods (T0 and T1), comparisons were made between the direct and indirect visual dexterity test scores. In addition, the Mann-Whitney U test was used to compare results across gender. The statistical significance (p-value) was set at below 0.05 with a confidence level of 95%. RESULTS: A statistically significant difference was detected between the T0 and T1 assessments on the Purdue Pegboard Test and the O'Connor Tweezer Dexterity Test for all selected dentistry students in both direct and indirect conditions (p < 0.001). CONCLUSION: Further investigation in other dental departments or schools, particularly those with different entry standards, is required prior to making a definitive conclusion about the use of these dexterity assessments as predictors of prospective dental students' performance.

Teeth Whitening and Antibacterial Effects of Juglans regia Bark: A Preliminary Study.

OBJECTIVES: Natural folk medicines with antimicrobial effects have been under investigation during the past decades. The aim of this study was to evaluate the teeth whitening and antimicrobial effects of ethanol extract of Persian walnut "Juglans regia" barks. MATERIALS AND METHODS: Minimum inhibitory concentration (MIC) was determined using a broth microdilution assay which was conducted through a 2-fold serial dilution method, and a whitening experiment was done in vitro on extracted teeth, with a pH test being performed on 2-fold dilutions of the ethanol extract. RESULT: It was found that the MIC for Enterobacter and E. coli and Staphylococcus and Pseudomonas was found to be 5 mg/ml and 2.5 mg/ml, respectively. Both dilutions were found to be acidic, and the extract of Juglans regia bark also demonstrated the ability of teeth whitening. CONCLUSION: This study supports the use of Juglans regia bark as a natural product in dentistry because of the confirmed antimicrobial ability as well as its whitening effect. Clinical Relevance. Herb extract might be incorporated within commercially available kinds of toothpaste to enhance its whitening and antimicrobial effects.