A survey on NiTi rotary instruments usage by endodontists and general dentist in Tehran

INTRODUCTION: The aim of this study was to assess the extent of adoption, application and the associated issues with the nickel-titanium (NiTi) rotary instruments and techniques amongst endodontists and general dentists in Tehran.MATERIALS & METHODS: A total of 33 questions classified in six categories of demographics, frequency rate of NiTi rotary instrumentation and information. The sample size comprised of 100 endodontists and 100 general dental practitioners in Tehran. RESULTS: The overall response rate was 73.5%. NiTi rotary instruments were used by 98.4% and 50.6% of endodontists and general dentists, respectively. The main mentioned reason for not using rotary NiTi instruments was "lack of education". Among all procedural faults with NiTi, the most prevalent was “intra-canal file fracture” (88.5%) followed by "apical transportation" (71.2%) and "ledging" (68.3%). The main factors associated with the first procedural accident were "over-use" and “excessive pressure”. CONCLUSION: Dentists need more training and more comprehensive education regarding NiTi rotary instruments and techniques.

Root and Canal Morphology of Maxillary Teeth in an Iranian Subpopulation Residing in Western Iran Using Cone-beam Computed Tomography

Introduction: Accurate information regarding the morphology of roots and canals is a prerequisite for successful endodontic treatment. This study aimed to assess the number of roots and canals and canal type of maxillary teeth according to the Vertucci’s classification in an Iranian subpopulation residing in Western Iran using cone-beam computed tomography (CBCT). Methods and Materials: In this cross-sectional study, a total of 1750 teeth were evaluated on CBCT scans taken for purposes other than this study. For each tooth, 250 axial, sagittal and coronal sections with 1 mm slice thickness were evaluated using NNT Viewer software. The number of roots and canals and canal type according to the Vertucci’s classification were determined and reported. Data were analyzed using descriptive and analytical statistics via Fisher’s exact test and Chi square test. All data analyses were performed using SPSS version 18. Results: All of the maxillary anterior teeth were single-rooted, and Vertucci’s type I was the most common canal type. Maxillary premolars were mostly single-rooted and Vertucci’s type I was the most common type except for the first maxillary premolars, in which type V had the highest frequency. Maxillary molars mostly had three roots and two canals in the mesiobuccal root and one canal in the distobuccal and palatal roots. Conclusion: Although the number of roots in this cross-sectional study was similar to the findings of previous studies, canal type was significantly different from the results of previous studies. The result of this study can help clinicians in efficient root canal treatment of teeth.Keywords: Cone-beam Computed Tomography; Maxilla; Root Canal Morpholog

Oral health status among Iranian veterans exposed to sulfur mustard: a case-control study

Background: Sulfur mustard (SM) is a chemical warfare agent that has been repeatedly used since World War I. SM has chronic and deleterious effects on different body organs such as lungs, skin and eyes. Objectives: To determine dental and oral health status of chemical victims of SM who were exposed to SM during the Iraqi-Iran war. Material and Methods: In this case-control study, 100 male subjects exposed to SM were chosen as cases, and 100 non-exposed volunteers were chosen as controls. These groups were selected randomly according to their referral number, and were matched regarding age. Collection of information was performed using Oral Health Assessment Form designed by the World Health Organization. Quantitative and qualitative data were compared between the groups using independent samples t-test and Chi-square test, respectively. Results: There was a significant difference between the case and control groups with respect to the frequencies of oral candidiasis, pharyngeal erythema and/or hyperplasia, hairy tongue and reflux disease, being higher in the former group. There was also a positive association between the frequency of candidiasis and the percentage of disability; pharyngeal erythema and/or hyperplasia and use of salmeterol spray; and between hairy tongue and antibiotic use in the case group. Conclusions: Exposure to SM and the use of drugs for controlling long-term complications does not increase the risk of tooth decay, tooth loss, and intra and/or extra oral lesions in patients, but may be associated with increased incidence of oral candidiasis, pharyngeal erythema and/or hyperplasia, hairy tongue and reflux disease

A Randomized Triple-Blind Clinical Trial of the Effect of Low-Level Laser Therapy on Infiltration Injection Pain in the Anterior Maxilla

Objective: To evaluate the level of pain experienced during infiltration anesthesia of the anterior maxilla following low-level laser therapy (LLLT) with 810-980 nm wavelengths. Material and Methods: In the current triple-blind clinical trial, 84 patients received a total of 168 infiltration anesthesia injections (1.8 mL of 2% lidocaine plus 1:100,000 epinephrine) in the anterior maxilla. Each patient received two injections into the buccal mucosa of the right and left central incisors with a two-week interval. One injection was performed after LLLT, while the other injection was administered conventionally without laser. The pain level was measured immediately after injection using a visual analog scale (VAS). Results: There was a significant difference in the pain level experienced with and without LLLT, such that the mean pain score following LLLT was significantly lower than that without LLLT (p<0.05). No significant difference was found in the pain level between laser and no laser groups in males, but the difference in this regard was significant in females (p<0.05) and female patients experienced a significantly lower level of pain following LLLT. Conclusion: The low-level laser therapy can be successfully used to decrease the level of pain experienced during infiltration anesthesia of the anterior maxilla

Applying the Taguchi Method to the Optimization of Anticancer Activity of Bacterial Alginate-CuO Bionanocomposite

AIM: In recent decades, despite various types of cancer inflicting many people worldwide, the existing therapies are not satisfactory and have many side effects. The present study was conducted to optimise the synthesis of novel alginate-CuO nanocomposite with utmost anticancer activity. METHODS: In this study, 9 nanocomposites were designed using Taguchi method and three factors including copper oxide nanoparticles, alginate biopolymer and stirring times were assessed at three different levels. The anticancer activity of the synthesised nanocomposites was evaluated on the MCF-7 cell line using the MTT method. Using the Qulitek-4 software, we determined the optimum conditions for the synthesis of alginate-CuO nanocomposite with the highest anticancer activity. RESULTS: The results indicated that all three factors (copper oxide, alginate and stirring time) were effective on the anticancer activity of the alginate-CuO nanocomposite. Also, the nanocomposite produced under the conditions of experiment 9 (8 mg/ml of copper oxide, 2 mg/ml of alginate and 60 min of stirring time) provided the highest growth inhibition rate as 75.63% against cancer cells. CONCLUSION: The synthesised alginate-copper oxide nanocomposites in this study showed a significant anticancer effect. Therefore, the synthesised nanocomposite under optimal conditions can be used in the design of new anticancer drugs

The Role of Nanomaterials in the Treatment of Diseases and Their Effects on the Immune System

Nanotechnology has been widely exploited in recent years in various applications. Different sectors of medicine and treatment have also focused on the use of nanoproducts. One of the areas of interest in the treatment measures is the interaction between nanomaterials and immune system components. Engineered nanomaterials can stimulate the inhibition or enhancement of immune responses and prevent the detection ability of the immune system. Changes in immune function, in addition to the benefits, may also lead to some damage. Therefore, adequate assessment of the novel nanomaterials seems to be necessary before practical use in treatment. However, there is little information on the toxicological and biological effects of nanomaterials, especially on the potential ways of contacting and handling nanomaterials in the body and the body response to these materials. Extensive variation and different properties of nanomaterials have made it much more difficult to access their toxicological effects to the present. The present study aims to raise knowledge about the potential benefits and risks of using the nanomaterials on the immune system to design and safely employ these compounds in therapeutic purposes

A Randomized Triple-Blind Clinical Trial of the Effect of Low-Level Laser Therapy on Infiltration Injection Pain in the Anterior Maxilla

Objective: To evaluate the level of pain experienced during infiltration anesthesia of the anterior maxilla following low-level laser therapy (LLLT) with 810-980 nm wavelengths. Material and Methods: In the current triple-blind clinical trial, 84 patients received a total of 168 infiltration anesthesia injections (1.8 mL of 2% lidocaine plus 1:100,000 epinephrine) in the anterior maxilla. Each patient received two injections into the buccal mucosa of the right and left central incisors with a two-week interval. One injection was performed after LLLT, while the other injection was administered conventionally without laser. The pain level was measured immediately after injection using a visual analog scale (VAS). Results: There was a significant difference in the pain level experienced with and without LLLT, such that the mean pain score following LLLT was significantly lower than that without LLLT (p<0.05). No significant difference was found in the pain level between laser and no laser groups in males, but the difference in this regard was significant in females (p<0.05) and female patients experienced a significantly lower level of pain following LLLT. Conclusion: The low-level laser therapy can be successfully used to decrease the level of pain experienced during infiltration anesthesia of the anterior maxilla

Effect of Continuous Positive Airway Pressure on Changes of Plasma/Serum Ghrelin and Evaluation of These Changes between Adults with Obstructive Sleep Apnea and Controls: A Meta-Analysis

Background and objective: Obstructive sleep apnea (OSA) can be related to high ghrelin hormone levels that may encourage additional energy intake. Herein, a new systematic review and meta-analysis were performed to check the changes in serum/plasma levels of ghrelin in adults with OSA compared to controls, as well as before compared after continuous positive airway pressure (CPAP) therapy in adults with OSA. Materials and methods: Four main databases were systematically and comprehensively searched until 17 October 2022, without any restrictions. For assessing the quality, we used the Joanna Briggs Institute (JBI) critical appraisal checklist adapted for case&ndash;control studies and the National Institutes of Health (NIH) quality assessment tool for before&ndash;after studies. The effect sizes were extracted by the Review Manager 5.3 software for the blood of ghrelin in adults with OSA compared with controls, as well as before and after CPAP therapy. Results: Fifteen articles involving thirteen studies for case&ndash;control studies and nine articles for before&ndash;after studies were included. The pooled standardized mean differences were 0.30 (95% confidence interval (CI): &minus;0.02, 0.61; p = 0.07; I2 = 80%) and 0.10 (95% CI: &minus;0.08, 0.27; p = 0.27; I2 = 42%) for case&ndash;control and before&ndash;after studies, respectively. For thirteen case&ndash;control studies, nine had moderate and four high qualities, whereas for nine before&ndash;after studies, five had good and four fair qualities. Based on the trial sequential analysis, more studies are needed to confirm the pooled results of the analyses of blood ghrelin levels in case&ndash;control and before&ndash;after studies. In addition, the radial plot showed outliers for the analysis of case&ndash;control studies that they were significant factors for high heterogeneity. Conclusions: The findings of the present meta-analysis recommended that the blood levels of ghrelin had no significant difference in the adults with OSA compared with the controls, nor did they have significant difference in adults with OSA before compared with after CPAP therapy. The present findings need to be confirmed in additional studies with more cases and higher qualities

Buccolingual Inclination of Canine and First and Second Molar Teeth and the Curve of Wilson in Different Sagittal Skeletal Patterns of Adults Using Cone-Beam Computed Tomography

Objectives. This study aimed to assess the buccolingual inclination of canine and first and second molar teeth and the curve of Wilson in different sagittal skeletal patterns in untreated adults using cone-beam computed tomography (CBCT). Materials and Methods. Sixty-six CBCT scans of adults (mean age: 28.74 ± 5.25 years) were evaluated in this cross-sectional study. The images were standardized using the Frankfurt horizontal plane and the interorbital line. The sagittal skeletal pattern was determined using the ANB angle and Wits appraisal. Inclination angles were measured by NNT Viewer and Mimics software. The curve of Wilson was measured by connecting the tips of mesiobuccal and mesiolingual cusps of maxillary first and second molars along the buccal groove and measuring the formed angle. Data were analyzed using ANOVA. Results. The intraobserver agreement was 0.969. The mean inclination of maxillary first and second molars in class I and III patients was significantly higher than that in class II patients P0.05. The mean curve of Wilson in second molars of class II patients was significantly higher than that in class I patients P<0.05. Conclusion. In different sagittal skeletal patterns, a compensatory relationship exists between the opposing teeth, which, along with the standards of crowns, can be used to determine the appropriate position of teeth in dental arch

Shear Bond Strength of Metal and Ceramic Brackets to Composite Using Single Bond and Universal Adhesive

AIM: This study aimed to assess the shear bond strength (SBS) of metal and ceramic brackets bonded to composite restorations using single bond 5th generation bonding agent and G-Premio Bond universal adhesive. MATERIALS AND METHODS: In this in vitro, experimental study, 60 sound extracted human premolars were veneered with composite and were then randomly divided into four groups (n = 15) of Single Bond + Transbond XT + metal brackets, universal adhesive + Transbond XT+ metal brackets, Single Bond + Transbond XT + ceramic brackets, and universal adhesive + Transbond XT + ceramic brackets. Twenty-four hours after thermocycling, the SBS of brackets was measured using a universal testing machine. The adhesive remnant index (ARI) score was also determined under a stereomicroscope. Two-way ANOVA was used to compare the groups (p &lt;0.05). RESULTS: No significant difference was found in the mean SBS of ceramic and metal brackets or between the two bonding agents (p &gt; 0.05). The interaction effect of type of bracket and type of bonding agent on SBS was not significant (p &gt; 0.05). ARI score I had the highest frequency in Single Bond + Metal bracket group. The highest frequency of ARI score V was noted in the Single Bond + Ceramic bracket group. A comparison of ARI scores of metal bracket groups showed a significant difference between single bond and universal adhesive (p = 0.002). CONCLUSION: Both adhesives can provide adequate SBS for the bonding of metal and ceramic brackets to composite restorations