Antiapoptotic and antioxidative effects of cerium oxide nanoparticles on the testicular tissues of streptozotocin-induced diabetic rats: An experimental study

Background: Cerium dioxide nanoparticles (CNPs) due to the antidiabetic and antioxidant activities are proposed for the treatment of oxidative stress-associated diseases. Objective: To examine the impact of CNPs on hyperglycemia-induced apoptosis and oxidative stress in the testis of diabetic rats. Materials and Methods: Twenty-four male rats were divided into four groups (n = 6/each) as diabetic rats, CNPs group, diabetic + CNPs rats, and controls. The control group was fed only mouse food and water. Rats became diabetic through receiving streptozotocin (STZ) 60 mg/kg. CNPs were given to the rats at a dose of 30 mg/kg daily for 2 wk. Malondialdehyde and total thiol group (TTG) levels were measured using spectrofluorometer. Expression of b-cell lymphoma protein 2-associated X protein (BAX) and b-cell lymphoma protein 2 (Bcl-2) were investigated using quantitative real-time polymerase chain reaction. Western blot analysis was used to examine caspase 3 protein levels. Results: The content of malondialdehyde significantly increased in the STZ-diabetic rats, while TTG levels demonstrated a remarkable decrease. Caspase-3, BAX, and BAX/Bcl-2 mRNA ratio raised significantly in the STZ-diabetic rats. On the other hand, Bcl-2 mRNA levels reduced in the testis of diabetic rats (p = 0.006). Intervention with CNPs caused a substantial increase in the TTG levels, while the malondialdehyde contents, caspase-3, BAX levels, as well as BAX/Bcl-2 mRNA ratio were considerably decreased following CNPs treatment. Administration of CNPs increased mRNA levels of Bcl-2 (p < 0.0001). Conclusion: CNPs treatment attenuates testicular apoptosis and oxidative stress induced by diabetes. This nanoparticle might be suggested for the treatment of diabetes-associated reproductive disorders. Key words: Apoptosis, Nanoceria, Diabetes, Oxidative stress, Testis

Comparison of Marginal Circumference of Two Different Pre-crimped Stainless Steel Crowns for Primary Molars After Re-crimping

Objectives: It is not clear what type of pre-crimped crown is more successful in achieving greater marginal adaptation following re-crimping. This study aimed to assess the changes in the circumference of 3M ESPE and MIB pre-crimped stainless steel crowns (SSCs) for the primary maxillary and mandibular first and second molars following re-crimping. Materials and Methods: This was an in-vitro, experimental study. Initial photographs were obtained from the margins of 3M and MIB SSCs for the upper and lower primary molars using a digital camera. Crown margins were crimped by applying 0.2N force using 114 and 137 pliers. Post-crimping photographs were also obtained and the changes in crown circumference after crimping were calculated using AutoCad software. The percentage of reduction in the circumference of crowns for each tooth was statistically analyzed based on the type of crown using student t-test. The effect of crown design and the associated teeth on the decreased circumference percentage was statistically analyzed by two-sided ANOVA. Results: The percentage of reduction in lower E SSC circumference was 3.71±0.39% in MIB and 6.29±0.62% in 3M crowns. These values were 3.55±0.55% and 7.15±1.13% for the lower Ds, and 3.95±0.43 and 6.24±0.85% for the upper Ds, respectively. For the upper Es, these values were found to be 3.12±0.65% and 5.14±0.94%, respectively. For each tooth, a significant difference was found between MIB and 3M SSCs in terms of the percentage of reduction in crown circumference following crimping. The magnitude of this reduction was smaller in MIB compared to 3M SSCs (P<0.001). Conclusion: Considering the significant reduction in the marginal circumference of pre-crimped SSCs following re-crimping, it appears that this manipulation must be necessarily performed for MIB and 3M pre-crimped SSCs. By using 3M SSCs, higher marginal adaptation can be achieved following crimping

Accuracy of Ipex-I and Root ZX Mini Electronic Apex Locators and Conventional Radiography in Determining Root Canal Length in Primary Molars with Root Resorption: A Narrative Review

Background and purpose: One of the main goals in pediatric dentistry is to maintain deciduous teeth until the permanent teeth grow. In cases where the pulp of deciduous teeth is involved, pulpectomy is needed which requires determining the correct working length of the canals and cleaning and filling their interior space using a proper filling material. The principles of successful endodontic treatment in permanent teeth are well known, but, determining the anatomy of the canal of deciduous teeth is difficult due to the resorption and deposition of hard tissue in the root canal, the shape, dimensions, and variable conditions of root apex. Therefore, in this narrative review, we investigated the accuracy of Ipex-I and Root ZX mini electronic apex locators and conventional radiography in root canal length determination in resorbed primary molars. A thorough search was conducted in Science Direct, Google Scholar, PubMed, Scopus, Irandoc, SID, Magiran, and Iranmedex covering the articles published in 2000–2020. According to findings, all techniques mentioned were found to have almost similar accuracy in determining the working length in resorbed deciduous molars. However, obtaining radiography images may be difficult in children, therefore, apex locators are more preferable to the conventional method