Occupational Exposure to Physical and Chemical Risk Factors: A Systematic Review of Reproductive Pathophysiological Effects in Women and Men

The human reproductive system can be affected by occupational exposure to many physical and chemical risk factors. This study was carried out to review the studies conducted on the issue of the pathophysiological effects of occupational physical and chemical risk factors on the reproductive system of females and males. In this systematic review, the databases such as “Google Scholar,” “Pub-Med,” “Scopus,” and “Web of Science” were used. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020), the studies included in our study were published between 2000 and 2021. In order to extract the required data, all sections of the articles were reviewed. Out of 57 articles we reviewed, 34 articles were related to field studies and 23 articles to clinical studies. Among them, 43 studies dealt with the pathophysiological effects of chemical agents, six studies dealt with the pathophysiological effects of physical factors, and 8 studies dealt with the pathophysiological effects of physicochemical factors on the human reproductive system. Physical (noise, heat, and radiofrequency radiation) and chemical (such as carbamate and organophosphate pesticides, benzene, toluene, xylene, formaldehyde, NO2, CS2, manganese, lead, nickel, and n-hexane) risk factors had pathophysiological effects on the human reproductive system. The presence of these risk factors in the workplace caused damage to the human reproductive system. The rate of these negative pathophysiological effects can be reduced by performing appropriate managerial, technical, and engineering measures in work environments.

Oral rehabilitation of Papillon–Lefèvre syndrome patients by dental implants: a systematic review

Objectives@#Papillon–Lefèvre syndrome (PLS) is a rare autosomal recessive disorder. These patients lose their teeth at a young age and are in need of prosthetic rehabilitation. The aim of this systematic review was to assess the success of dental implant placement in these patients. @*Materials and Methods@#An electronic search was performed in PubMed Central, Scopus, and Web of Science using the keyword “Papillon–Lefèvre syndrome” AND “dental implant” OR “prosthodontics”. Articles reporting implant placement in patients with PLS until July 2019 were included. @*Results@#Assessment of the included 11 articles reporting 15 cases showed 136 implant placements in these patients. Implant failure occurred in 3 patients (20 implants). The peri-implantitis and failure rate was higher in the maxilla. Meta-analysis showed the probability of failure to be 7% (95% confidence interval [CI] 0%-31%) for maxillary implants and 2% (95% CI 0%-9%) for mandibular implants. The follow-up time ranged between 1 and 20 years. Healing after bone graft and implant placement in these patients was uneventful. @*Conclusion@#Dental implants may be a viable treatment option for PLS patients. Implantation can help preserve alveolar bone if the patients’ immunological and growing conditions are well-considered and proper oral hygiene and compliance with the maintenance program are continued.

Diagnostic accuracy of CT scan for detection of cervical lymph node metastasis in oral squamous cell carcinoma in comparison with histopathological analysis after neck dissection

Objectives: presence/absence of cervical lymph node metastasis plays a critical role in prognosis and survival of patients with oral squamous cell carcinoma [SCC]. This study was designed to assess the diagnostic accuracy of computed tomography [CT] scan for detection of cervical lymph node metastasis in oral SCC in comparison with histopathological analysis after neck dissection

Methods: in this retrospective cross-sectional study, pathology and CT reports of 50 patients with oral SCC were retrieved from the archives of Taleghani and Shariati Hospitals and data regarding the site of involvement, lymph node metastasis, level of cervical involvement and size of involved lymph node were retrieved from patient files. The results of CT scan and pathology reports were compared and the accuracy, sensitivity, specificity, positive predictive value [PPV] and negative predictive value [NPV] of CT scan were calculated compared to the gold standard [pathology report]. Basic statistics was meed for analyz the data

Results: the sensitivity of CT scan for detection of metastatic cervical lymph nodes was 69.23% compared to the pathology report [gold standard]. The specificity, PPV and NPV were 27.02%, 25% and 71.42%, respectively. The diagnostic accuracy of CT scan was 38%

Conclusion: based on the results, CT scan is not reliable for detection of metastatic cervical lymph nodes in oral SCC, and more advanced techniques may be indicated for assessment of cervical lymph node involvement and deciding on the most efficient surgical approach in patients with oral SCC

Effect of cement type on the color attributes of a zirconia ceramic

PURPOSE: This in vitro study evaluated the effects of four different cements on the color attributes of a zirconia ceramic. MATERIALS AND METHODS: 40 zirconia ceramic disk specimens (0.5 mm thickness, 10 mm diameter, 0.1 mm cement space) were fabricated by a computer-aided design and computer-aided manufacturing system. The specimens were divided into 4 groups of 10 specimens and cemented to composite substrates using four different cements including: Glass Ionomer, Panavia F2.0, Zinc Phosphate, and TempBond. The L*, a*, and b* color attributes of the specimens were measured before and after cementation by a spectrophotometer. Additionally, ΔE values were measured to determine color changes for the groups and then compared with the perceptional threshold of ΔE = 3.3. Repeated Measures ANOVA, Tukey Post Hoc, Bonferroni, One-way ANOVA, and One-sample t-test tests were used to analyze the data. All tests were carried out at the 0.05 level of significance. RESULTS: Statistically significant differences were detected in the ΔE values for Zinc Phosphate (P<.0001) and TempBond (P<.0001) groups. However, there were no statistically significant differences in this respect for Glass Ionomer (P=.99) and Panavia F2.0 (P=1) groups. The means and standard deviations of the ΔE values for Glass Ionomer, Panavia F2.0, Zinc Phosphate, and Tempbond groups were 2.11±0.66, 0.94±0.39, 5.77±0.83, and 7.50±1.16 Unit, respectively. CONCLUSION: Within the limitations of this study, it was concluded that Zinc Phosphate and Tempbond cements affected the color attributes of the tested zirconia ceramic beyond the perceptional threshold. However, Glass Ionomer and Panavia F2.0 cements created acceptable color changes.

Analysis of longitudinal binary outcomes in clinical trials with low percentage of missing values

In interventional or observational longitudinal studies, the issue of missing values is one of the main concepts that should be investigated. The researcher's main concerns are the impact of missing data on the final results of the study and the appropriate methods that missing values should be handled. Regarding the role and the scale of the variable that missing values have been occurred and the structure of missing values, different methods for analysis have been presented. In this article, the impact of missing values on a binary response variable, in a longitudinal clinical trial with three follow up sessions has been investigated Propensity Score, Predictive Model Based and Mahalanobis imputation strategies with complete case and available data methods have been used for dealing with missing values in the mentioned study. Three models; Random intercept, Marginal GEE and Marginalized Random effects models were implemented to evaluate the effect of covariates. The percentage of missing responses in each of the treatment groups, throughout the course of the study, differs from 6.8 to 14.1. Although, the estimate of variance component in random intercept and marginalized random effect models were highly significant [p <0.001] the same results were obtained for the effect of independent variables on the response variable with different imputation strategies. In our study according to the low missing percentage, there were no considerable differences between different methods that were used for handling missing data

Study motives and career choices of Iranian medical and dental students

To compare the study motives and career choices of senior undergraduate medical and dental students in Iran. A cross-sectional questionnaire-based survey study involving final year medical and dental students from 4 dental and medical schools was conducted in 2010. The questionnaire was designed in three sections [Demographic details, motivational items and career choice items] and after confirming the validity and reliability of the questions, it was distributed among the students. Data were entered into SPSS; statistical analysis included logistic regression and multiple linear regression. The response rate was 62% [n=219] for medical and 64% [n=300] for dental students. The factor analysis identified six motivational items: "Social and professional status", "Health care and people", "Others' recommendation", "personal interest and nature of occupation", "Occupational experience" and "Personal life". Medical students were more influenced by "Playing a role in community health" and "Personal interest". "Work independence" and "Social factors" however were two major influential factors among dental students. There were significant differences in important influences by age [Social and professional status, Others' recommendation], Parents' education [Social and professional status, Health care and people, Personal life] and marital status [single >married: Occupational experience, married > single: Personal life]. Engaging in postgraduate studies was the first career preference among 90.9% and 89.8% of dental and medical students respectively. Medical and dental students report a wide range of motivational factors in studying medicine/dentistry and future career plans which is affected by age, parents' education and marital status

Accuracy of the methodology section of graduate and post-graduate theses in Shahid Beheshti medical university, school of dentistry from March 2009 to October 2011

The purpose of this study was to investigate the histologic interaction Theses are among the most important research sources of the universities and should be authored according to the international standards of scientific writing. The present study aimed at determining the accuracy of the methodology section of graduate and post-graduate theses conducted in Shahid Beheshti Medical University, School of Dentistry from March 2009 to October 2011. In this descriptive cross-sectional study all approved theses of the Shahid Beheshti Medical University, School of Dentistry from March 2009 to October 2011 were evaluated according to the international check lists. For data analysis, SPSS version 16.0 software, ANOVA and independent ttest were used. A total of 101 theses with observational design and 72 with experimental design were evaluated. The mean conformity of observational theses with STROBE check list was 75%. The highest conformity was observed in the complete description of inclusion and exclusion criteria [95%] while the lowest conformity was observed in the bias control [48%]. The mean conformity of the interventional theses with all the items of CONSORT checklist was 62%. The highest conformity was found in complete description of the type and process of intervention [90.3%] whereas the lowest conformity was found in allocation concealment mechanism [88%]. No significant correlation was found between the presence of a consulting professor and academic ranking of the thesis instructor and the mean score of thesis. In observational theses, the lowest conformity was observed in the description of the bias control; whereas, in interventional theses the lowest conformity was detected to be in allocation concealment mechanism

Socioeconomic links to health-related quality of life, anxiety, and depression in kidney transplant recipients

The impact of socioeconomic status on the chance of being a candidate of kidney transplantation and its effect on graft survival has been documented. Our aim was to investigate the association of socioeconomic status with kidney allograft recipients' health-related quality of life and level of anxiety and depression. Two hundred and forty-two kidney transplant recipients were categorized according to their monthly family income into low-income, moderate-income, and high-income groups. These groups were compared in terms of health-related quality of life [short form-36] and level of anxiety and depression symptoms [hospital anxiety depression scale]. There was a trend of higher HRQOL scores in association with a higher income, which was significant for the total HRQOL score and its subdomains of physical function and role limitation due to physical and emotional problems. A slight increase in anxiety symptom scores was also seen in kidney recipients with lower incomes; however, the depression symptom scores were not significantly different between the income groups. Logistic regression analysis showed that the impact of income on the total HRQL and anxiety symptoms scores remained significant after controlling the effect of age, sex, and time interval from transplantation. A significant proportion of our kidney allograft recipients had a low income and had a poorer health-related quality of life and a greater load of anxiety according to their perception of their status, compared to those with higher incomes. Special consideration to kidney transplant recipients with a lower income may improve their wellbeing

Survival of rehospitalized kidney allograft recipients

Undergoing transplantation is extremely stressful, and a recipient is likely leave the hospital burdened with fears of an uncertain future. A paucity of knowledge on the long-term survival of rehospitalized kidney transplant recipients is the likely the reason that physicians fail to provide this group of patients with promising information and reassurance about their future. We sought to describe the long-term patient and graft survival after nonfatal rehospitalization in kidney recipients with a normal graft function after discharge. We reviewed the follow-up data [from the time of discharge after first rehospitalization] of 253 kidney transplant recipients who had been discharged from rehospitalization with a normal kidney function [serum creatinine less than 1.6 mg/dL]. Patient and graft survival rates 6 months and 1, 2, and 5 years after discharge were determined. The mean duration of follow-up [from the time of discharge after the first rehospitalization] was 38.9 +/- 11.2 months [range, 6 to 84 months]. The overall patient survival rates were 98%, 97%, 95%, and 93% at 6 months, 1 year, 2 years, and 5 years, respectively. Graft survival rates at these times were 88%, 82%, 77%, and 63%, respectively. After the first posttransplant rehospitalization, 54 patients [21.9%] experienced more hospitalization episodes [mean, 2.6 +/- 2.0 times], while 193 [78.1%] had no further hospitalizations during the follow-up period. Kidney transplant recipients who are rehospitalized should be reassured about favorable chances of survival if discharged with a normal graft function