Tooth eruption sequence and dental crowding: a case-control study.

UNLABELLED: When cases of dental crowding are identified and diagnosed promptly, interceptive orthodontics is particularly successful. AIM: To assess the differences in the eruption sequence of the mandibular canine and first premolar teeth in children with and without dental crowding. MATERIALS AND METHODS: Children who attended the Shiraz Dental School's orthodontic clinic (Iran) from September to December 2012 were enrolled in this case-control study. Tooth size arch length discrepancy (TSALD) of all 8-10 year olds was calculated from patients' dental models. Thirty-six children were randomly selected from those with TSALD of equal or less than 4mm (those with crowding). Each selected case was matched for sex and age with another child (as control) with TSALD>-4mm attending the same clinic, in the same time period. The existing panoramic radiographs were traced and the eruption percentages were measured for mandibular canine and first premolar teeth. The mean difference between canine and first premolar eruption percentages was compared between the case and control groups using the SPSS (version PASW 18) software and a paired sample t-test. RESULTS: Canine and first premolar eruption percentages in the case group were 65.82±13.00 and 78.92±10.15 percent, respectively. The mean eruption percentages for canines and first premolars of the control group were 74.12±14.55 and 75.47±11.60 percent, respectively. There was a significant difference in pre-eruptive positions of canine and first premolar teeth in those with moderate to severe crowding when compared to the control group (p<0.001). CONCLUSION: These findings may improve the early diagnosis of children with high risk of developing moderate to severe crowding during mixed dentition

Outcomes of orbital decompression for thyroid eye disease over a 10-year period at a tertiary eye care referral center

Background: Orbital decompression is frequently indicated to treat exophthalmos and compressive optic neuropathy, among other indications for thyroid eye disease (TED). This study aimed to evaluate the outcomes of orbital decompression and compare the results by urgency and type of surgery in patients with TED. Methods: In this cross-sectional study, we recruited patients with TED who had undergone emergency or elective orbital decompression surgery at a tertiary eye care referral center in Tehran, Iran, between 2010 and 2020. Ophthalmic examination findings, demographic and clinical profiles, and types and outcomes of surgical interventions were reviewed and analyzed. Results: Fifty-one orbits of 35 patients with a mean (standard deviation [SD]) age of 36.2 (12.0) years and male-to-female ratio of 23 (66%)/12 (34%) were included. The mean (SD) duration from the diagnosis to the surgery was 41.0 (39.0) months. The surgical method was fat decompression in 1 (2%) orbit; fat and inferior wall decompressions in 2 (4%) orbits; fat, inferior, and medial wall (two-wall) decompressions in 43 (84%) orbits; and fat, inferior, medial, and lateral wall (three-wall) decompressions in five (10%) orbits. Three-wall decompression surgery resulted in significantly lower exophthalmometry readings than those associated with two-wall surgery at all postoperative follow-ups (P &lt; 0.05). Ten (20%) orbits required emergency decompression because of sight-threatening conditions and revealed comparable exophthalmometry readings with electively decompressed orbits at the 1-year visit (P &gt; 0.05). Thirty-seven (73%) orbits required other surgeries within the 1-year follow-up. The mean (SD) exophthalmometry readings before and 1-year after surgery were 26.3 (4.0) and 18.3 (2.7) mm, respectively, with a significant decrease and significant 5.5 (3.3)-mm change from baseline in decompressed orbits (both P &lt; 0.001). Diplopia was reported in 29% (n = 10) of patients less than 2 months postoperatively. Conclusions: Emergency or elective orbital decompression significantly reduced exophthalmos in patients with TED within 1 year postoperatively. Three-wall orbital decompression produced the more immediate impact, while two-wall orbital decompression showed the higher effect at a later timepoint. The most common complication was diplopia, while other serious complications occurred infrequently. Further prospective comparative studies involving more participants and longer postoperative follow-up periods are required to verify these preliminary findings

Precisión de las radiografías digitales bitewing con y sin aplicación de desplazamiento horizontal del tubo en el diagnóstico del exceso de cemento residual alrededor de los implantes dentales: Un estudio in vitro.

Purpose: This study was designed to evaluate the diagnostic value of digital Bitewing (BW) radiographs with and without horizontal tube shift in detecting Residual excess cement (REC) on the proximal and non-proximal surfaces of implant restorations. Material and Methods: Eight mandibular models were fabricated with two implants placed on each side in the premolar and first molar positions. Excess cement was applied to either proximal or non-proximal surfaces of the restorations intentionally during the process of crown cementation. BW radiographs with and without applying horizontal tube shift were acquired. Three maxillofacial radiologists were asked to determine the presence and location of REC in the radiographs. Sensitivity and specificity of the radiographic technique were assessed according to the restoration surface that contained REC. Results: Sensitivity of BW radiographs was 100% for the detection of REC on the proximal surfaces and 41-18, 80% on the non-proximal surfaces. Specificity of the technique was 85.71%-100% for the proximal surfaces and 75-94. 12% for the non-proximal areas. Specificity of the radiographic method was generally greater than its sensitivity for the non-proximal surfaces while in the proximal areas, the two variables had quite similar values. Conclusion: Digital BW radiography is generally more useful for detection of REC on the proximal surfaces. Higher specificity of this technique for the bucco-lingual surfaces suggests more reliability of the negative diagnoses in the non-proximal areas.Objetivo: Evaluar el valor diagnóstico de las radiografías digitales bitewing (BW), con y sin desplazamiento horizontal del tubo, para detectar el exceso de cemento residual (ECR) en las superficies proximales y no proximales de las restauraciones con implantes. Material y Métodos: Se fabricaron ocho modelos mandibulares con dos implantes colocados a cada lado en las posiciones premolar y primer molar. El exceso de cemento se aplicó intencionalmente en las superficies proximales o no proximales de las restauraciones durante el proceso de cementación de la corona. Se adquirieron radiografías BW con y sin aplicación de desplazamiento horizontal del tubo. Se pidió a tres radiólogos maxilofaciales que determinaran la presencia y ubicación de ECR en las radiografías. La sensibilidad y la especificidad de la técnica radiográfica se evaluaron según la superficie de restauración que contenía ECR. Resultados: La sensibilidad de las radiografías de BW fue del 100% para la detección de ECR en las superficies proximales y del 41,18-80% en las superficies no proximales. La especificidad de la técnica fue 85-71, 100% para las superficies proximales y 75-94, 12% para las áreas no proximales. La especificidad del método radiográfico fue generalmente mayor que su sensibilidad para las superficies no proximales, mientras que en las áreas proximales, las dos variables tuvieron valores bastante similares. Conclusión: La radiografía digital BW es generalmente más útil para la detección de ECR en las superficies proximales. La mayor especificidad de esta técnica para las superficies buco-linguales sugiere una mayor confiabilidad de los diagnósticos negativos en las áreas no proximales

Identifying Birds' Collision Risk with Wind Turbines Using a Multidimensional Utilization Distribution Method

Renewable energy plays a key role in reducing greenhouse gas emissions. However, the expansion of wind farms has raised concerns about risks for bird collisions. We tested different methods used to understand whether birds' flight occurs over wind turbines and found kernel density estimators outperform other methods. Previous studies using kernel utilization distribution (KUD) have considered only the 2 horizontal dimensions (2D). However, if altitude is ignored, an unrealistic depiction of the situation may result because birds move in 3 dimensions (3D). We quantified the 3D space use of the Griffon vulture (Gyps fulvus) in El Estrecho natural park in Tarifa (southern Spain, on the northern shore of the Strait of Gibraltar) during 2012-2013, and, for the first time, their risk of collision with wind turbines in an area in the south of Spain. The 2D KUD showed a substantial overlap of the birds' flight paths with the wind turbines in the study area, whereas the 3D kernel estimate did not show such overlap. Our aim was to develop a new approach using 3D kernel estimation to understand the space use of soaring birds; these are killed by collision with wind turbines more often than any other bird types in southern Spain. We determined the probability of bird collision with an obstacle within its range. Other potential application areas include airfields, plane flight paths, and tall buildings. (c) 2020 The Authors. Wildlife Society Bulletin published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.Peer reviewe

Evaluation of Palatal Bone Thickness and Its Relationship with Palatal Vault Depth for Mini-Implant Insertion Using Cone Beam Computed Tomography Images

Objective: The purpose of this study was to measure the thickness of the palatal bone using cone beam computed tomography images for placement of mini-screws and their relationship with palatal vault depth.Methods: This study was performed on 150 maxillary cone beam computed tomography images, 50% (n = 75) had deep palate and 50% (n = 75) had normal palate and 27.3% (n = 41) were male and 72.7% (n =109) were female. Coronal sections with a thickness of 1 mm were prepared at distances of 4 mm, 8 mm, 12 mm, 16 mm, 20 mm, and 24 mm from the posterior wall of the incisive foramen. Then, in each section, in the midsagittal line and at distances of 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm from that to the lateral sides, the bone thickness was measured. The Korkhaus index was used to identify the patients with a high palatal vault.Results: The results showed that at the posterior sections in the midsagittal and parasagittal area, a significant difference (P < .05) was observed between deep and normal palate, and in these points, the bone thickness in the normal palate was greater. Also, in the section of 4 mm and 8 mm, a significant difference was observed between males and females in most of these points, and those were greater in males than females.Conclusion: The maximum thickness of the palatal bone was observed first along the midsagittal line and then the paramedian and in the anterior section. Patients with deep palate had less palatal bone thickness in the posterior sections

Effect of Age on the Score of the Persian Version of the University of Cincinnati Auditory Processing Inventory: A Pilot Study

Background and Aim: The Persian version of the University of Cincinnati Auditory Processing Inventory (P-UCAPI) is used to evaluate auditory processing disorders in Iranian people using six subscales, each focusing on different auditory skills. In this study, we aimed to compare the total score and the subscale scores of the P-UCAPI among three age groups to evaluate the impact of aging on auditory processing. Methods: Participants in three age groups of 20, including 21–39 years (group A), 42–60 years (group B), and 61–80 years (group C) completed the P-UCAPI. One-way ANOVA and Welch’s t-test was used to compare the mean scores of each subscale among the three groups. Results: The mean scores of listening and concentrating (p<0.001), understanding speech (p<0.001), attention (p=0.010), and other (p<0.001) were significantly lower in group C compared to group A. The mean scores of listening and concentrating (p=0.001), understanding speech (p<0.001), and other (p<0.001) were significantly lower in group C compared to group B. The mean total score was not significantly different between groups A and B (p=0.333). However, the difference was significant between groups A and C (p<0.001) and between groups B and C (p<0.001). Conclusion: The increase of age affects the auditory processing and generally reduces the auditory performance

Cone-Beam Computed Tomographic Assessment of Bone Thickness in the Mandibular Anterior Region for Application of Orthodontic Mini-Screws

Objective: To determine the proper zones for placement of orthodontic mini-screws, based on cone-beam computed tomography (CBCT) measurements in the anterior mandibular region.Methods: The current cross-sectional study was performed on CBCT images of 77 individuals in the age range of 18-60 years. Axial slices at the levels of 2, 5, and 8 mm from the cementoenamel junction (CEJ) of the mandibular anterior teeth were selected. Interdental distances were measured in the mesiodistal direction, parallel to the midline of the mandibular arch. Areas with more suitable width were investigated for measuring the minimum interdental space. On the reconstructed cross-sectional images, labiolingual thickness of the bone was measured at the levels of 2, 5, 8, and 11 mm from the CEJ. The Kruskal–Wallis test, Mann–Whitney test with Bonferroni correction, Welch test, and Tukey’s multiple analogy test were used to analyze the data.Results: Mesiodistal and labiolingual distances between the roots in every measured region had the highest values at the levels of 8 and 11 mm from the CEJ. The highest measured values were related to the interdental region between the lateral incisor and canine teeth on both sides of the arch. There were no statistically significant differences between these values (P < .001).Conclusion: The lateral incisor–canine areas at the level of 8 mm from the CEJ are introduced as the optimal sites for placement of orthodontic mini-screws. In addition, the results recommend the application of mini-screws with 1.3-1.7 mm diameter and 5-7 mm length

Risk-based avilable transfer capability (ATC) assessment including non-diaspatchable generation

Available Transfer Capability (ATC) is a measure for assessing the capability between different areas of the power systems which are governed by non-linear power flow equations. ATC contains different complicated parts. Total transfer capability (TTC) and two margins; transmission reliability margin (TRM) benefit margins (CBM) are the main parts which have to be considered for accurate calculation. This report conducts the ATC evaluation with the main part, TTC, by a continuation power flow algorithm (CPF). CPF is an attractive method for non-linear equations and specially is used as the solution to power flow equations due to its capability for solving the power flow algebraic equations at the bifurcation nose point. CPF algorithm has been compared with other types for power flow equation solution algorithms and obtained based on its superior characteristics over them. Integration of wind farms into the IEEE 30-bus test system at a different location was successfully done. non-dispatchable generation impacts on ATC value has been checked by considering the probabilistic method for wind turbine power output, while both thermal and voltage system limitations have been applied. Results show that, available transfer capability is dramatically declined by considering these power system limitations. In addition, integrating of the wind farm into the test system has increased the power system loading parameter and similarly ATC. It was shown that by changing the location of injected wind power into the power system, ATC is changed. This change firmly depends on the voltage profile level of the connected bus into the wind farm and also weather conditions in the wind farm