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This study aimed to assess the effect of inferior alveolar nerve (IAN) block of the mandible and infiltration anesthesia of the maxilla using lidocaine plus epinephrine or prilocaine with felypressin anesthetic agents on systolic and diastolic blood pressures, heart rate (HR) and peripheral oxygen saturation rate of patients. This randomized double-blind clinical trial evaluated 112 patients in four groups (n=28) based on the jaw (maxilla or mandible) and type of anesthetic agent (lidocaine with epinephrine or prilocaine with felypressin). Groups 1 and 2 received IAN block of the mandible or infiltration anesthesia of the maxilla, respectively, with 2% lidocaine plus 1:80.000 epinephrine. Groups 3 and 4 received IAN block of the mandible or infiltration anesthesia of the maxilla, respectively, using prilocaine with felypressin. Systolic and diastolic blood pressures and HR were measured by an automatic upper arm blood pressure monitor and the percentage of peripheral oxygen saturation rate was measured by a finger pulse oximeter 10 minutes before the injection, immediately after injection, 10 minutes after injection and 20 minutes after injection.

The purpose of the current research is to optimize the synthesis of sodium hyaluronatetitanium dioxide nanocomposite with the highest anticancer activity. To this end, the Taguchi method was followed to design nine experiments with different ratios of sodium hyaluronate biopolymer, titanium dioxide nanoparticles and stirring times. The results of scanning electron microscopy (SEM) confirmed the synthesis of the nanoparticle and nanocomposite. The comparison of anticancer activity level of synthesized nanocomposites using MTT assay showed that the nanocomposite synthesized in the conditions of experiment 9 (8 mg/ml of titanium dioxide nanoparticles, 2 mg/ml of sodium hyaluronate biopolymer and 60 min stirring time) had the maximum anticancer activity against Michigan Cancer Foundation-7 (MCF-7) cell line. According to the results, the Taguchi method can be employed as an effective and useful strategy to save time and cost in order to determine the optimal conditions for the synthesis of sodium hyaluronate-titanium dioxide nanocomposite with the most favorable anticancer activity.

This paper investigates symmetrical buckling of orthotropic circular and annular plates of continuous variable thickness. Uniform compression loading is applied at the plate outer boundary. Thickness varies linearly along radial direction. Inner edge is free, while outer edge has different boundary conditions: clamped, simply and elastically restraint against rotation. The optimized Ritz method is applied for buckling analysis. In this method, a polynomial function that is based on static deformation of orthotropic circular plates in bending is used. Also, by employing an exponential parameter in deformation function, eigenvalue is minimized in respect to this parameter. The obtained results show that in plate with identical thickness, increasing of outer radius decreases the buckling load factor.

Abstract Background Retention is an important aspect of orthodontic treatment. This study aimed to analyze the survival of three types of maxillary and mandibular bonded orthodontic retainers. Methods This retrospective cohort study evaluated the records of 118 orthodontic patients (90 females, 28 males, mean age of 22.34 ± 6.44 years) retrieved from a private orthodontic office. Data regarding the retainer failure, dental caries, unwanted tooth movements, maximum pocket depth (PD), and bleeding on probing (BOP) recorded at the follow-up sessions were extracted from patient records. Three types of retainer wires namely Bond-A-Braid, Orthoflex, and Retainium were compared regarding the abovementioned parameters. Data were analyzed by ANOVA, Chi-square, Monte-Carlo Chi-square, and Kruskal Wallis tests, the log rank test, and the Cox regression model. Results The frequency of retainer failure was not significantly different between males and females, different age groups, or different treatment durations (P > 0.05). Wire fracture was the most common failure type in both the maxilla and mandible. Also, the frequency of failure was not significantly different between the maxillary and mandibular retainers (P > 0.05). The frequency of failure, and survival of the three types of retainer wires were not significantly different during a 5-year period (P > 0.05). Conclusions The three types of orthodontic retainers had comparable survival rates. Their failure rate was not correlated with the age or gender of patients or the treatment duration.

Objectives: This study aimed to assess the prevalence and configuration of C‐shaped canal morphology in maxillary molars in an Iranian population residing in Kermanshah Province of Iran using cone‐beam computed tomography (CBCT). Materials and Methods: This cross‐sectional study was conducted on 2290 CBCT scans of 804 maxillary first molars, 1049 maxillary second molars, and 437 maxillary third molars. The Maxillary Upper‐C Classification System was used for the detection of C‐shaped canal morphology, and the classification by Jo et al. was used for assessment of the configuration of C‐shaped canals. Data were analyzed by the Chi‐square test (α = 0.05). Results: The prevalence of C‐shaped canals in the maxillary first, second, and third molars was 1%, 7%, and 9%, respectively. Type III other types (B‐P) was the most frequent configuration followed by type I subtype C (MB‐DB). The prevalence of C‐shaped canal morphology was not significantly different among different age groups (p > 0.05); however, its prevalence in females was almost twice that in males (p < 0.05). The prevalence of C‐shaped canals was not significantly different in the right and left quadrants (p = 0.099). The most frequent configuration was type I subtype B (DB‐P) in males, and type III other types (B‐P) in females (p = 0.364). Conclusion: The prevalence of C‐shaped canals in maxillary first, second, and third molars was 1%, 7%, and 9%, respectively. C‐shaped canals were more common in females, and type III other types (B‐P) was the most frequent configuration in our study population. [ABSTRACT FROM AUTHOR]

Background: This study was aimed to assess the implant-related anatomical landmarks in the mandibular interforaminal region in an Iranian population using cone-beam computed tomography (CBCT). Methods: In this retrospective cross-sectional study, 378 CBCT images of the mandible were evaluated for the presence of the incisive canal, anterior loop of the inferior alveolar nerve (IAN), mandibular canal, mental foramen, and incisive canal. The effect of age and gender of patients on the abovementioned variables was also evaluated. Data were analyzed using independent t-test, analysis of variance, and Chi-square test. Results: The anterior loop and the incisive canal were present in 36.24% and 97.62% of the cases, respectively. The mean length of the anterior loop and the incisive canal was 2.70 ± 1.20 mm and 12 ± 3.29 mm in the right, and 2.86 ± 1.24 mm and 12.21 ± 3.38 mm in the left side, respectively. The mean diameter of the mental foramen and incisive canal was 4.25 ± 1.08 mm and 1.89 ± 0.46 mm in the right, and 4.21 ± 1.02 mm and 1.94 ± 0.45 mm in the left side, respectively. The descending path was the most common path of the incisive canal. The distance from the incisive canal to the buccal plate and inferior border of the mandible was significantly shorter in females (P < 0.001). Conclusion: Considering the high variability and clinical significance of the incisive canal and anterior loop of the IAN, and their high prevalence, it is recommended to assess the presence/absence of these structures in the interforaminal region of the mandible on CBCT scans before surgical procedures in this region.

Objective: To assess the effect of experience in landmark identification on two-dimensional (2D) lateral cephalograms on performance of dental students concerning landmark identification on three-dimensional (3D) cone-beam computed tomography (CBCT) scans. Material and Methods: This quasi-experimental study evaluated 40 dental students in two groups (n=20). Group 1 included senior dental students who had experience in landmark identification on 2D lateral cephalograms and Group 2 included third-year dental students with no such experience. Both groups received instructions on identification of eight landmarks on 3D CBCT scans. The coordinates of the landmarks were determined in x, y and z axes. One orthodontist determined the mean coordinates of each landmark as a reference by twice measurements with a one-week interval. The mean distance from the identified points to the reference points was reported as the mean consistency (MC), and the standard deviation of the mean was considered as precision of landmark identification. Data were analyzed using independent samples t-test. Results: The mean distances from the points identified as nasion, point B, orbitale, anterior nasal spine (ANS), menton, coronoid process and pogonion in x, y and z axes and point A in x and z axes (p

Abstract Background Considering the increasing popularity of electronic learning, particularly smartphone-based mobile learning, and its reportedly optimal efficacy for instruction of complicated topics, this study aimed to compare the efficacy of smartphone-based mobile learning versus lecture-based learning for instruction of cephalometric landmark identification. Methods This quasi-experimental interventional study evaluated 53 dental students (4th year) in two groups of intervention (n = 27; smartphone instruction using an application) and control (n = 26, traditional lecture-based instruction). Two weeks after the instructions, dental students were asked to identify four landmarks namely the posterior nasal spine (PNS), orbitale (Or), articulare (Ar) and gonion (Go) on lateral cephalograms. The mean coordinates of each landmark identified by orthodontists served as the reference point, and the mean distance from each identified point to the reference point was reported as the mean consistency while the standard deviation of this mean was reported as the precision of measurement. Data were analyzed using SPSS version 18 via independent sample t-test. Results No significant difference was noted between the two groups in identification of PNS, Ar or Go (P > 0.05). However, the mean error rate in identification of Or was significantly lower in smartphone group compared with the traditional learning group (P = 0.020). Conclusions Smartphone-based mobile learning had a comparable, and even slightly superior, efficacy to lecture-based learning for instruction of cephalometric landmark identification, and may be considered, at least as an adjunct, to enhance the instruction of complicated topics. Trial registration number This is not a human subject research. https://ethics.research.ac.ir/ProposalCertificateEn.php?id=33714&Print=true&NoPrintHeader=true&NoPrintFooter=true&NoPrintPageBorder=true&LetterPrint=true .

Abstract Background This meta-analysis evaluated the association of LTF, ENAM, and AMELX polymorphisms with dental caries susceptibility. Methods We searched the Scopus, PubMed/Medline, Web of Science, and Cochrane Library databases to retrieve articles published by October 2019. Review Manager 5.3 software was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). The results of publication bias tests were retrieved by Comprehensive Meta-Analysis 2.0 software. Results A total of 150 relevant records were identified; out of which, 16 were entered into the analysis (4 studies assessed LTF, 11 ENAM, and 11 AMELX polymorphisms). Of all polymorphisms, there was a significant association only between ENAM rs3796704 polymorphism and dental caries susceptibility. Both ENAM rs3796704 and AMELX rs17878486 polymorphisms had a significant association with dental caries risk in the Caucasian ethnicity and the studies including caries-free control group. Conclusions The results of this meta-analysis showed that the G allele and the GG genotype of ENAM rs3796704 were associated with an increased risk of caries in the case group compared with the control group. But there was no association between LTF rs1126478, ENAM (rs1264848 and rs3796703), and AMELX (rs946252, rs17878486, and rs2106416) polymorphisms and dental caries susceptibility.

Objectives. Some correlations have been proposed between chronic rhinosinusitis (CRS) and type and severity of nasal septal deviation. This study sought to compare the type and severity of nasal septal deviation between CRS patients undergoing functional endoscopic sinus surgery (FESS) and asymptomatic controls using cone-beam computed tomography (CBCT). Materials and Methods. This prospective case-control study evaluated 49 CRS patients who did not respond to pharmaceutical therapy and were candidates for FESS and 49 asymptomatic controls. All participants underwent CBCT and were inspected for septal deviation type and severity. Data were analyzed by the independent t-test and chi-square test. Results. The study population comprised of 58.25% males and 41.8% females, with a mean age of 33.74 ± 11.78 years. Significant correlations were noted between the presence of CRS and severity of septal deviation (P=0.007). Type of septal deviation had no significant correlation with the presence of CRS (P=0.443). Conclusion. Patients with CRS have significantly more severe nasal septal deviation. However, type of septal deviation is not correlated with CRS.

Increasing resistance of microbes to available antimicrobial agents has necessitated the production of new compounds with wider activity and lower toxicity. Candida is one of the pathogenic fungal strains that are highly prevalent in oral diseases. The goal of this study was to optimize the biosynthesis of selenium nanoparticles (NPs) with the suitable antifungal activity on Candida albicans oral pathogen. For this purpose, selenium NPs were synthesized by the green method using the Halomonas elongata bacterium. To optimally synthesize NPs with the maximal antifungal properties, 9 experiments were planned applying the Taguchi method. In the planned experiments, the efficacy of 3 factors, sodium selenite concentration, glucose concentration, and incubation time at 3 various levels was studied, and the most desirable conditions with the suitable performance were determined. Then, optimizing the synthesis of the studied nanoparticles, their properties were evaluated using Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), electron transmission microscopy (TEM), and thermogravimetric analysis (TGA) to confirm the synthesis of nanoparticles with suitable conditions. The results demonstrated that the synthesized NPs in the experiment 9 condition showed the best performance and prevented more than 70% of fungal growth. Since selenium NPs were effective as an antifungal agent, they can be used in the structure of mouthwashes as an antimicrobial agent in the prevention and treatment of many oral diseases.

Abstract Background Frailty assessment is a critical approach in assessing the health status of older people. The clinical tools deployed by geriatricians to assess frailty can be grouped into two categories; using a questionnaire-based method or analyzing the physical performance of the subject. In performance analysis, the time taken by a subject to complete a physical task such as walking over a specific distance, typically three meters, is measured. The questionnaire-based method is subjective, and the time-based performance analysis does not necessarily identify the kinematic characteristics of motion and their root causes. However, kinematic characteristics are crucial in measuring the degree of frailty. Results The studies reviewed in this paper indicate that the quantitative analysis of activity of daily living, balance and gait are significant methods for assessing frailty in older people. Kinematic parameters (such as gait speed) and sensor-derived parameters are also strong markers of frailty. Seventeen gait parameters are found to be sensitive for discriminating various frailty levels. Gait velocity is the most significant parameter. Short term monitoring of daily activities is a more significant method for frailty assessment than is long term monitoring and can be implemented easily using clinical tests such as sit to stand or stand to sit. The risk of fall can be considered an outcome of frailty. Conclusion Frailty is a multi-dimensional phenomenon that is defined by various domains; physical, social, psychological and environmental. The physical domain has proven to be essential in the objective determination of the degree of frailty in older people. The deployment of inertial sensor in clinical tests is an effective method for the objective assessment of frailty.

Background: Chemical treatments for the modulation of host response are applied along with mechanical modalities as adjunctive to periodontal treatment. The objective of this pilot study was to investigate the effects of locally-delivered alendronate sodium gel in adjunction to scaling and root planning on periodontal indices and bone formation within vertical defects of smokers with chronic periodontitis. Methods and Materials: In this study vertical defects (n=8) with depth>5 mm have been investigated. After performing the phase I of periodontal treatment, alendronate sodium gel (1%) was applied into the periodontal pockets. The whole procedure was repeated after 4 weeks. Periodontal indices (plaque and bleeding), probing depth, gingival recession, and radiographic parameter (depth of bony defect) were measured at the beginning and following 6 months. Results: Compared to pre-treatment, the probing depth, radiographic depth of bony defect and bleeding and plaque indices were significantly reduced by local application of alendronate sodium gel (P=0.026; P=0.012 and P=0.007 respectively). Gingival recession showed significant increase (P=0.011). Conclusion: Local alendronate sodium gel (1%) plays an important role in the improvement process of periodontal indices and bone formation within vertical bony defects of smoker patients with chronic periodontitis.

Objectives: Minimizing the frictional force between orthodontic wire and brackets is imperative to safely obtain a more favorable result by applying lower loads. Several methods have been proposed for this purpose such as changing the wire shape/size, changing the bracket design, and coating wires with different materials. This study aimed to assess the effect of zirconium oxide (ZrO2) nano-coating on frictional resistance of three types of orthodontic wires. Materials and Methods: This in vitro, experimental study evaluated 42 pieces of nickel-titanium (NiTi), stainless steel (SS), and beta-titanium (TMA) orthodontic wires, and 42 maxillary canine brackets. The samples were divided into six groups with and without ZrO2 nano-coating. The nano-coating was applied on the wires using the sol-gel technique. The presence of ZrO2 nano-coating was evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The surface roughness of the samples was evaluated using atomic force microscopy (AFM). The brackets and wire had a 5° angle relative to each other. The static and kinetic friction of the samples were evaluated in the presence of artificial saliva and occlusogingival movements in a universal testing machine. Data were analyzed by the Shapiro–Wilk's test, one-way ANOVA, Kruskal–Walli's test, Mann–Whitney U test, independent t-test, and Tukey's test. Results: ZrO2 nano-coating was only observed on TMA wires. The surface roughness of coated NiTi and SS wires had no significant difference from that of non-coated wires (P > 0.05). However, this difference was significant for TMA wires with and without the coating (P < 0.05). The static and kinetic friction were not significantly different between wires with and without coating (P > 0.05). Conclusions: ZrO2 nano-coating could only be applied on TMA wires, and had no significant efficacy for reduction of static or kinetic friction of TMA wires.