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Background: The evaluation of treatment-associated errors is important in the radiotherapy process, particularly those resulting related to patient setup. Objective: This research aimed to assess the interfractional setup errors and determine the Clinical Target Volume to Planning Target Volume (CTV to PTV) margin in patients undergoing 3-Dimensional Conformal Radiation Therapy (3DCRT) for head and neck cancer by means of electronic portal imaging device. Material and Methods: In this analytical study, 300 portal images were acquired from 50 patients undergoing 3DCRT for head and neck cancer. Using the portal images of Lateral (LAT) and Antero-Posterior (AP) fields, population systematic (∑) and random (σ) errors were obtained in the lateral, longitudinal, and vertical directions. Finally, based on the International Commission on Radiation Units and Measurements (ICRU) Report 62's, Stroom's and Van Herk's methods, Planning target volume margins were determined. Results: The translational shift ranges were 0-8.1 mm in the ML, 0-9 mm in the SI (AP), 0-8.8 mm in the SI (LAT), and 0-10 mm in the AP directions. The population systematic and random errors were respectively 3.230, 2.753, and 2.997 mm, and 1.476, 1.853, and 1.715 mm in X, Y, and Z directions. The calculated PTV margins using the ICRU-62, Stroom's, and Van Herk's formulae were ranging from 3.236-3.551, 6.605- 7.493, and 7.932-9.108 mm, respectively. Conclusion: A PTV margin of 7.5-9.5 mm seems safe for ensuring adequate treatment volume coverage. In addition, the EPID is an effective equipment for verifying patient positioning and reducing treatment setup errors. [ABSTRACT FROM AUTHOR]

Objectives: Dental clinics are one of the major producers of mercury-containing waste due to the use of dental amalgam. The atmospheric transport and persistence of mercury and its compounds in the environment, coupled with their high potential for bioaccumulation and detrimental effects on human health and ecosystems, underscore the necessity for effective management of mercury waste. Due to the lack of comprehensive and integrated guidelines for the effective management of dental amalgam waste in Iran, the objective of this study was to adapt a guideline for the management of amalgam waste in dental settings within the country. Materials and Methods: The method used was based on the adaptation principles presented by the Ministry of Health and Medical Education, and included searching and reviewing guidelines related to the management of amalgam waste in developed countries, extracting recommendations, revising the recommendations considering the local infra-structures and conditions, and receiving expert opinions and reaching consensus according to the RAND/UCLA Appropriateness Method. Results: The final guideline includes 34 recommendations in 5 areas: management of the amalgam scraps, considerations for dental equipment, management of the extracted teeth containing amalgam restorations, management of the amalgam capsules, and considerations for placement and replacement of the amalgam restorations. Conclusion: The use of this guideline in medical universities, public and private dental clinics, along with the supervisory role of the Ministry of Health and Medical Education, can be a way to minimize the environmental hazards of mercury. [ABSTRACT FROM AUTHOR]

Objective: The impact of the deep margin elevation (DME) technique and its associated materials on the stress distribution in ceramic endocrowns remains to be fully understood. This finite element analysis (FEA) aimed to assess the effects of flowable composite and resin‐modified glass ionomer (RMGI) as DME materials on the maximum Von Mises stress (VMS) values and overall stress distribution within ceramic endocrowns and the surrounding tooth structure. Materials and Methods: A mandibular molar featuring a class II mesio occlusal (MO) cavity with the gingival margin of the mesial cavity positioned 2 mm below the cementoenamel junction (CEJ) was prepared and scanned using a Medit i500 scanner. The digital file was then transferred to computer‐aided design (CAD) software to create the models. The study generated four scenarios: an intact tooth model (model of intact tooth (MIT)), a prepared tooth model without a DME layer (model without DME (MWD)), a model with a 2 mm DME layer using composite material (model with DME of composite (MDC)), and a model employing RMGI (model with DME of RMGI (MDR)). Stress distribution under axial loads was evaluated based on the Von Mises criterion. Results: The MIT model demonstrated the highest stress concentration at the CEJ region yet exhibited lower stress levels than others. The MWD model showed the highest stress levels. No significant differences in stress distribution patterns were observed between the MDR and MDC models. All models displayed similar stress distributions in the bone. Conclusion: Regardless of the material used, incorporating a DME layer in cavities extending below the CEJ is advisable to achieve uniform stress distribution. Minimizing tooth preparation and preserving tooth structure are recommended. Clinical Significance: Employing a DME layer in cavities with margins below the CEJ is beneficial for reducing stress, irrespective of the material choice. [ABSTRACT FROM AUTHOR]

The presence of residual antibiotics and the excessive accumulation of metals beyond permissible limits in milk represent significant health challenges. This study aimed to analyse the levels of heavy metals and trace elements in raw milk from Kurdistan province using inductively coupled plasma mass spectrometry (ICP‐MS) following digestion via thermal block. Subsequently, the samples were evaluated for contamination with MRSA (methicillin‐resistant Staphylococcus aureus), taking into account the potential correlation between methicillin‐resistant strains and metal accumulation. Finally, milk safety was assessed based on the presence of toxic metals. A total of 180 milk samples were examined. Among them, 13.34% were found to be contaminated with S. aureus, and of those, 62.48% tested positive for MRSA. The metal concentrations (mg/kg) were measured as follows: arsenic 7 × 10−2 ± 6 × 10−3, cadmium 4.70 × 10−1 ± 9.70 × 10−2, lead 7 × 10−2 ± 5 × 10−3, mercury 3 × 10−2 ± 9 × 10−3 and iron 4 × 10−2 ± 9 × 10−3. Interestingly, arsenic, cadmium and iron levels were found to be correlated with the presence of MRSA. Additionally, there was an inverse relationship between toxic metals and essential ones in samples sensitive to methicillin (P < 0.001). The Target Hazard Quotient (THQ) for cadmium is indicated at 9.94. Furthermore, the calculated Carcinogenic Risk (CR) parameters for cadmium and arsenic were 6.06 × 10−3 and 2.22 × 10−4, respectively, suggesting that their concentrations fall within the carcinogenic range. The coexistence of MRSA and metal contamination in raw milk highlights the potential risks linked to its consumption. Consequently, the adoption of rigorous hygiene protocols is imperative to effectively address these concerns. [ABSTRACT FROM AUTHOR]

Background: Cystic echinococcosis (CE) is a parasitic and zoonotic infection, recognized globally as a neglected disease, with significant morbidity and mortality rates, especially in low-advantaged countries. We aimed to evaluate the recurrence rate after hydatid disease surgery in Fars Province, Iran. Methods: A retrospective design was used to examine the data collected from Nemazee and Shahid Faghihi Hospitals, Shiraz, southern Iran, over eight years, from 2011 to 2019. The research was conducted in 2023. The study extracted the following data from hospital records: demographic characteristics, paraclinical findings (such as sonography and CT scan), organ involvement, cyst number and size, surgical procedure, cyst complications, intraoperative or postoperative complications, and recurrence rate. Results: The study included 303 patients, of whom recurrence occurred in 36 (11.9%). Intra or postoperative complications were associated with recurrence (P=0.001). In the recurrent cases, the most common intraoperative complication was anaphylactic shock (P=0.001), and the most common postoperative complications were unresolved pneumothorax and empyema (P=0.001). There was a significant association between recurrence and complicated cysts (P=0.001). There was no significant difference between the organ involved and the complicated cyst in the recurrence (P=0.50). There was no association between increasing the cyst's size and the chance of the recurrence rate. There was a significant relationship between recurrence and the number of cysts in the affected organ (P=0.001). There was a significant association between using no scolicidal agents and recurrence (P=0.001), and no antiparasitic drugs were used in only one (2.7%) patient (P=0.3240). There was no significant association between recurrence and duration of admission (P=0.193). Conclusion: Intra or postoperative complications (anaphylactic shock, unresolved pneumothorax, and empyema), complicated cysts, the number of cysts in the affected organ, and injecting of no scolicidal agents were significantly associated with recurrence. Recurrence may have many reasons, such as insufficient drainage (incomplete peri-cystectomy and minute spillage of cyst contents), missing hidden cysts (numbered cysts), rupture or spillage of the cysts, and inadequate medical treatment. [ABSTRACT FROM AUTHOR]