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Summary Introduction The aim of this study was to three-dimensionally compare the root angulation changes after orthodontic traction of buccally versus palatally maxillary impacted canines (MICs). Material and methods This retrospective study included patients from a private dental office of both sexes, older than 12 years, with at least one unilateral or bilateral buccal or palatal MIC, no loss of permanent teeth, with complete apical closure at the beginning of traction, and with CBCTs taken at pretreatment (T0) and after orthodontic traction (T1). The sample was divided in two groups according to their impaction site: buccal versus palatal. In all the scans, the MIC was segmented and the root angulation changes after traction were evaluated. The assessment included the sigma angle (projected on the XZ plane or coronal tomographic view), the delta angle (projected on the XY plane or axial view) and the epsilon angle (projected on the YZ plane, or sagittal view). Intragroup comparisons were performed with Wilcoxon signed-rank tests. Intergroup comparisons were performed with t-tests or Mann-Whitney U tests. Finally, the influence of MIC characteristics on the measured angles were evaluated with multiple linear regression analyses (α = 0.05). Results Thirty-three patients (16 men, mean age: 20.38; 17 women, mean age 18.37) with forty-five orthodontically treated MIC (19 buccal versus 26 palatal) were finally included. The palatal MICs showed greater mediolateral uprighting than the buccal MICs, root displacement towards the midsagittal plane, as demonstrated by the sigma angle (palatal group: 37.58 ± 15.08°; buccal group: 29.17 ± 31.15°; P = 0.164) and delta (palatal group: −76.90 ± 26.55°; buccal group: −30.56 ± 41.67°; P Conclusions Mediolateral and anteroposterior root angulation show significant differences after traction between buccal and palatal MICs. Palatal MICs showed greater medial root displacement while buccal MICs showed greater anterior root displacement. This condition should be considered for better planning of traction and orthodontic finishing.

The objective of this study was to evaluate the 3-dimensional changes in alveolar bone morphology after traction of buccally vs palatally unilateral maxillary impacted canines (MIC).Following a split-mouth model, 27 cone-beam computed tomography images of unilaterally MIC (14 palatally and 13 buccally) and 27 contralateral unimpacted controls were obtained before and after traction using nickel-titanium closed-coil springs and a rigid anchorage appliance. Alveolar bone height and width were measured in the axial, coronal, and sagittal slides by 3 calibrated orthodontists, taking into account the impaction characteristics. A t test was used to compare the 2 groups, and a paired t test was applied for intragroup comparisons (both sides). A multiple linear regression model was used to evaluate the influence of the predictor variables on alveolar bone dimensional changes.The alveolar height showed a significantly greater decrease in palatally MIC (2.09 to 2.79 mm) than buccally MIC (0.28 to 0.57 mm) (P 0.05) for all surfaces. However, the alveolar width increased similarly in both groups up to 1.36 mm. In general, the affected side had a more significant height loss and greater increases in alveolar width than the nonaffected side. Regression analysis indicated that buccally MIC and age decreased alveolar changes, whereas female sex increased alveolar changes (P 0.05).MIC traction with nickel-titanium closed-coil springs and heavy anchorage induces significant 3-dimensional changes in alveolar bone characterized by alveolar bone height decreases and cervical alveolar bone width increases. The height decrease is greater in palatally than in buccally MIC.

Introduction This study evaluated the influence of cone-beam computed tomography (CBCT) on endodondists' level of confidence in their diagnosis of endodontic cases and their treatment plans. Methods Twenty clinical cases with periapical radiographs and small-volume CBCT scans were classified according to the American Association of Endodontists guidelines. Information was provided on patient clinical history, and both extraoral and intraoral examinations were simulated. Fifteen endodontists filled out 2 questionnaires. In the first (Q1), the clinical description and a periapical radiograph were presented, followed by the questions. Thirty days later, they answered a second questionnaire (Q2) containing the same clinical description and CBCT. Their confidence in diagnosis and treatment planning was analyzed before and after receiving the tomographic images. Responses were recorded on a 5-point Likert scale, and the Wilcoxon test was used to investigate before and after levels of confidence in diagnosis and treatment planning. Results The CBCT images influenced confidence in diagnosis and treatment planning of endodontic cases classified as complex (Wilcoxon test; P ≤ .05). There was a substantial change in the treatment planned in both moderate and complex cases after CBCT. Case complexity did not affect the participants' decision to request complementary information through CBCT. Conclusions In complex cases, CBCT increased endodontists' confidence to diagnose and plan treatment, when compared with periapical radiographs. Endodontists tended to recommend intervention when periapical images were supplemented with CBCT. CBCT proved to be an imaging method that influences endodontists' preoperative evaluation and treatment choice.

Introduction The aim of this study was to compare the inclination and position changes of maxillary incisors after traction of unilateral vs bilateral maxillary impacted canines in nonextraction orthodontic treatment. Methods This longitudinal and retrospective study evaluated 24 patients with impacted maxillary canines; 12 with unilateral impaction and 12 with bilateral impaction. All subjects had Angle Class I malocclusion and were orthodontically treated with a standardized traction protocol that did not include premolar extractions. Cone-beam computed tomographies were obtained before and after canine traction and the inclination and position of both maxillary central incisors were measured. Furthermore, dental arch, skeletal, and canine impaction characteristics were evaluated. Paired and independent t tests were used for intra and inter group comparisons, respectively. Multiple linear regressions were also used. Results After canine traction, a significant incisor labial inclination was observed in the bilateral group (10.41° right side, P = 0.008 and 12.79° left side, P = 0.001), while in the unilateral group, this was observed only on the nonaffected side (6.67°, P = 0.008). Furthermore, a significant protrusion of incisors was observed in the bilateral group (2.66 mm right side, P = 0.006, and 3.15 mm left side, P = 0.001) and in the nonaffected side of the unilateral group (1.74 mm, P = 0.022). Intergroup comparisons showed greater values of incisor labial inclination for the bilateral group when compared with the unilateral group, independently of the sides. Conclusions Traction of maxillary impacted canines, in nonextraction treatment, produces greater labial inclination of maxillary incisors in bilateral cases and similar protrusion in both unilateral and bilateral cases. Unilateral impaction cases showed significant incisor inclination and protrusion in the nonaffected side. These treatment effects should be considered by clinicians.

Introduction Orthodontic traction of a maxillary impacted canine (MIC) increases the orthodontic treatment time. Therefore, the objective of this study was to evaluate the influence of MIC characteristics and factors associated with orthodontic treatment on the duration of active orthodontic traction. Methods This follow-up and retrospective study included 45 MICs orthodontically tractioned into the occlusal plane with the use of a standardized protocol. MIC characteristics, including type, sector, side, location, height, and complexity of impaction, as well as α and β angles and canine root length and area were measured. Likewise, factors associated with orthodontic treatment, including sex, age, malocclusion, premolar extractions, previous incisor root resorption, ANB, APDI, and SNA angles, and PNS-ANS distance were also evaluated. The statistical analysis included multiple linear regressions to estimate the influence of all variables on the duration of traction (α = 0.05). Results Sex had significant influence (P = 0.027) on the time of traction; in female patients, the time was 2.05 months more than in male patients. Bilateral impaction treatment increased the time by 2.74 months compared with unilateral cases (P = 0.001). Traction of bicortically centered impacted canines increased the duration of traction by 2.85 months (P = 0.001). Finally, the traction time increased in 2.35 months (P = 0.046) when the impaction sectors were 4 or 5 (close to the midline). Conclusions The duration of active orthodontic traction of MIC is mainly influenced by sex, bilateral type, bicortically centered location, or when MIC is located in sector 4 or 5 close to midline, increasing the traction time by some months.

Introduction The orthodontic traction of impacted canines is a procedure of variable complexity. The objective of this study was to determine the influence of this complexity on the root resorption (RR) of adjacent incisors, using cone-beam computed tomography. Methods This longitudinal retrospective study included 45 patients (19 female, 11 male; ages, 18.16 ± 7.3 years) with maxillary impacted canines, classified into 2 groups according to the level of orthodontic traction complexity: low complexity group (n = 20) and high complexity group (n = 25). The amounts of RR of 45 maxillary central and 45 lateral incisors were evaluated before and after treatment. Complexity was defined considering impaction sector, eruption inclination angle, and canine position (palatal, buccal, or bicortical). Three orthodontists measured RR in each maxillary incisor. Independent t tests or Mann-Whitney U tests were used to compare resorption between groups depending on the normality of the data. A multiple linear regression was calculated to evaluate the influence of all variables on RR (α = 0.05). Results RR of maxillary incisors in the sagittal, coronal, and axial sections showed no significant differences between groups (P > 0.05). Independently of the groups, RR ranged approximately from 1 to 1.5 mm and from 3 to 4 mm2. RR was less than 2 mm2 in the axial sections. Multiple linear regression indicated no significant influence of orthodontic treatment complexity on RR. Male patients had more RR, specifically in the maxillary central incisors than female patients (P Conclusions The complexity of orthodontic traction of impacted maxillary canines is not a risk factor for greater RR of maxillary incisors close to the impaction area.

Cycling helmets often incorporate elements aimed to dissipate rotational energies, which is widely acknowledged to play a key role in concussion mechanics. In this study, we investigated the mechanics of an oblique helmet test protocol that induced helmet rotation while using it to evaluate the effectiveness of three helmet models: two standard expanded polystyrene helmets and a commercially-available helmet equipped with a liner designed to mitigate linear and rotational energies.Helmets equipped with WaveCel were tested against two expanded polystyrene helmet models through guided drops using a Hybrid III (HIII) head-and-neck surrogate. The three helmet models were tested across four impact conditions (n = 5) of different speeds and impact surface angles.Across all tests, a similar sequence of head motion was observed - first a flexion phase followed by an extension phase. The extension phase lacked evidence of biofidelity and was likely attributable to the energy stored in the neckform during the flexion phase; it was therefore neglected from analysis. Results showed WaveCel reduced the probability of AIS2 head injury across all tests (3 to 27% reductions in 4.8 m/s impacts; 36 to 37% reductions in 6.2 m/s impacts).The two-phased response of the HIII suggests that boundary condition selection can influence results and should thus be reported in studies using similar methods. While this protocol involved both axial and tangential impact components and were thus representative of real-world collisions, the efficacy of WaveCel should be further investigated through additional laboratory studies and tracking real-world cycling injury statistics.

Purpose To evaluate the presence of calcifications in the internal carotid artery (ICA) in cone-beam computed tomography (CBCT), and to verify the association of these findings with sex, age, dental condition, and risk factors associated with vascular disorders. Methods The CBCT scans used in this study were obtained from the database of a private dental clinic requested for the planning of rehabilitation with dental implants. The selection criteria were patients aged 40 years and above. Out of a pool of 1,176 CBCT examinations, a total of 284 scans of adult patients were evaluated by two blinded observers. Data were collected from patients' medical records. Results ICA calcifications were present in 63.0% of the examinations. Most calcifications were in the intracranial pathway (166). Despite being present in a smaller number 57 (C1), extracranial calcifications were more severe. Spearman's ρ coefficients (rS) indicated that the number of missing teeth was directly associated with the presence of calcifications (p = 0.042) and severity (p = 0.020). The age variable also had a direct relationship with the presence of calcifications (p ≤ 0.0001), increasing its frequency and severity over the years. In addition, hypertension (p = 0.036) and use of antihypertensive drugs (p = 0.015) were directly associated. Conclusions There is a high occurrence of ICA calcifications in CBCT as incidental findings in adult patients, and it is directly associated with age, number of missing teeth and hypertension.

Objective: The aim of this study was to evaluate the accuracy of two craniometric methods for sexual prediction (SP) using cone-beam computed tomography (CBCT) in the Dutch population and to construct a formula for each method and then the two combined.Design: One-hundred sixty CBCT images were selected from a Dutch database (80 males and 80 females). The images were analyzed by two examiners taking seven measurements in the maxillary sinus (MS) region (first method) and nine in the mandibular canal (MC) region (second method). The most predictive measurements in both methods were used to develop an equation to determine the accuracy of each method.Results: All measurements showed statistical difference between genders. Logistic regression results showed two variables with greater SP index with 75% accuracy in the first method and four variables with 71.9% accuracy in the second. The two methods combined showed another four variables with 78.5% accuracy.Conclusion: All measurements showed statistically significant differences between sexes. The SP accuracy values were 75% for first 71.9% for the second method. When the two methods were combined, the accuracy increased to 78.5%. The formulas developed in this study can be applied as a complementary method for human identification in the Dutch population.

This work presents a methodology for a cloud-based condition monitoring system for fault detection and identification in rotating machines, such as uncoupling, angular and parallel misalignment, by data mining PROFINET network and PROFIdrive profile process data. The proposed methodology involves a new strategy for feature selection of unsupervised data set and employs SVM (Support Vector Machine) and OCSVM (One-Class Support Vector Machine) for operation status classification. The present diagnostic system represents a low-cost solution to the manufacturing process of small and medium enterprises, because it does not require dedicated sensors for fault detection and high featured hardware, and it employs an online cloud-based services. The experimental tests resulted in an accuracy between 87.5% and 100%, and high robustness among different operating conditions. In addition, the proposed feature selection strategy reduced the total execution time by 97.5%.

This paper proposes a study on the use of ring topology to increase availability of PROFINET networks. It discusses the influence of Media Redundancy Protocol (MRP), watchdog time, and the computational power of the PROFINET Controller on the communication recovery time after a ring fracture. The paper proposes to consider two main contributions to the overall recovery time: the first is related to the low level (Ethernet layer 2) redundancy management, while the second is related to the software configuration of the entire network. Several different configurations of networks have been created in laboratory and many others have been analyzed in real industry plants. The collected results show how watchdog could influence recovery time since its violation could trigger higher level routines whose duration is basically set by PROFINET controller computational capability. On balance, relevant suggestions to increase the availability of PROFINET networks are pointed out.

The purpose of the study presented in this article was to identify and summarize the sustainable practices adopted by producers of the red ceramic in a process of extraction and transportation of clay in a specific region. Initially designed as descriptive, the research combines bibliographic review with data collection, followed by qualitative and quantitative methods. The study sample was collected by interviewing the traditional producers located around Brazilian town of Prudentopolis in the state of Parana, Brazil. The article reveals the factors of economic, environmental and social impact of the industry as well as emphasizes the problematic aspects of relationships between production companies and local communities. The red ceramic industry is a significant part of the economic landscape in several a small municipality in the state of Parana. Even though the activities of clay extraction and transportation are inherently harmful for environment, local producers’ practices include recuperation techniques that somewhat allows to mitigate the consequences of the landscape degradation in a long run. The study revealed an environmental concern among companies’ managers and their conscious incentives to apply those recuperation measures. At the same time, we had to observe that a whole complex of the necessary activities was not implemented by any of the observed companies. The social impact of the industry is emphasized by its noise and pollution that causes tensions between companies and affected communities. Shortage of manual labour in the region can also be included into the list of socially determined challenges of the industrial actors.

The late Archaean Umburanas greenstone belt (UGB) is located in the Sao Francisco Craton, southwest of Bahia State, Brazil. The lower unit of UGB comprises basal komatiite lavas and tholeiitic basalts intercalated with felsic volcanic rocks. The regional crystalline basement rocks, the Gaviao block, predominantly consist of granitic, granodioritic and migmatitic gneiss along with tonalite-trondhjemite-granodiorite (TTG) associations. Petrographic studies of UGB komatiites reveal characteristic spinifex igneous texture although primary mineralogy is rarely preserved. Based on textural relationships, komatiites are divided into cumulate, spinifex, and massive types. The MgO content varies in the range 31.5–40.4 wt%. The MgO–SiO 2 negative correlation in komatiites suggests olivine fractionation trend. The UGB komatiites are of Al-undepleted type, characterized by Al 2 O 3 /TiO 2 (21–48) ratio, enriched in highly incompatible LILE relative to moderately incompatible HFSE and distinct negative Nb, Sr and Eu anomalies. Also shows depletion of light rare earths, convex-downward rare earth patterns typically not observed in komatiites world-wide, and primitive mantle normalized Gd/Yb (1.03–1.23) and La/Sm (2.36–4.99) ratios. The negative Eu anomaly is attributed to the circulation of H 2 O-rich fluid, whereas the negative Nb and Sr anomalies are attributed to contamination from granitic basement rocks of the Gaviao block. The UGB komatiites are most likely derived from adiabatic decompressional melting of a mantle plume. The melting took place at liquidus temperatures in the range 1572–1711 °C, which is consistent with mantle-plume origin invoked for several other komatiites in Archaean greenstone belts elsewhere. The melts were more likely generated at a depth shallower than 100 km (pressure

Introduction Studies to evaluate the diagnostic power of imaging examinations to detect root resorption have been based on simulations produced by burs. Standardized, round, and well-outlined access cavities do not reproduce the characteristics of physiological lesions and may facilitate diagnosis, masking the true accuracy of imaging techniques. A methodology to simulate internal root resorption by using acid demineralization was developed. Methods Eleven extracted single-rooted teeth were mesiodistally sectioned into homologous halves. Root canals were labeled to ensure restricted and controlled action of fluids. The protocol was composed of 24-hour cycles (5% nitric acid for 12 hours, rinsing with deionized water, and 8% sodium hypochlorite for 10 minutes). At the end of each cycle 1 tooth was removed from treatment, defining an exposure time that cumulated to the last tooth. Electron microscopy imaging was assessed to determine lesion area and depth. Results Minimum and maximum and areas and depths were 3.14 mm² and 10.34 mm² and 0.22 mm and 1.59 mm, respectively. Resorption simulated by the protocol proposed reproduced lesions of different sizes. Conclusions The irregular shape and larger diameter:depth ratio suggest that these lesions are more similar to in vivo internal root resorption, compared with bur-induced lesions.

Radiographic cephalometry is a complex area of study. The literature shows a lack of interobserver reproducibility in the definition and identification of cephalometric landmarks. The aim of this study was to test a learning virtual object (LVO) called ceph learning used in the teaching of radiographic cephalometry and to verify whether it improves performance of the landmarking process.A total of 40 undergraduate students were divided into 2 groups. Group A was taught according to the conventional teaching method of theory and practical classes, and group B was taught with an LVO. The students' learning performance was tested by using a multiple-choice questionnaire that covered the knowledge and understanding of cephalometry and by the index of correct landmark identification. The Student t test was used to check statistical differences between the 2 groups. LVO usability was evaluated with a questionnaire based on the system usability scale.In the first posttest, the Student t test showed no significant differences (P0.05). However, in the second posttest 15 days later, a decrease was observed in the scores of group A, with significant differences (P0.05). Students approved the LVO usability aspects--effectiveness, efficiency, and satisfaction (82.45% +/- 6.78%).LVO was shown to be a useful and efficient tool in the learning process and might assist the learning of cephalometry.

The literature has shown that subjective concepts lead to interobserver variations in the definitions and identifications of cephalometric landmarks. Observers must be trained and calibrated to conduct scientific research using cephalometric comparisons. In this study, we aimed to develop and test a computational model called Cyclops cephalometry in radiographic cephalometry training and calibration.This system uses the concepts of evaluation process managers, examiners, and testers, thus affording uniformity in cephalometric evaluations. The system was tested with 5 orthodontists and 5 postgraduate students who located 28 landmarks in 10 lateral cephalometric radiographs before and after training.Before training, the Student t test showed significant differences (P0.05) in accuracy between the orthodontists and the students (71.4% and 54.9%, respectively). However, considerable improvement in accuracy was observed after training in both groups (86.5% and 83%, respectively), without significant differences (P = 0.30) between groups. Users of the system agreed about its usability aspects such as effectiveness, efficiency, and satisfaction.This model was shown to be a useful and efficient tool in the calibration process, and might be helpful in various comparative cephalometric investigations.

This study assessed in vitro the diagnostic ability of cone beam computed tomography (CBCT) scans with different voxel resolutions in the detection of simulated external root resorption (ERR). For that purpose, 59 teeth were viewed through iCAT tomography (Imaging Sciences International, Inc, Hatfield, PA) following three protocols in which the variation was the voxel resolution (0.4, 0.3, and 0.2mm). A calibrated examiner blinded to the protocol assessed the images through the i-CAT View software (Imaging Sciences International, Inc). The chi-square statistical analysis did not show associations between voxel resolution, section plane, size of cavity, and radicular third. Sensitivity and specificity values were similar. However, likelihood ratio values of 6.4 for a 0.4-mm voxel, 16 for a 0.3-mm voxel, and 12 for a 0.2-mm voxel were found. It was concluded that CBCT is a reliable method for the investigation of simulated ERR, and a 0.3-mm voxel appeared to be the best protocol, associating good diagnostic performance with lower X-ray exposure. (J Endod 2009;35:233–235)

On this work, we draft an analysis of the principal aspects related to the modification of the role of the State after the Brazilian Federal Constitution of 1988 focus on the airport infrastructure’s exploration. In Brazil, the airport airport infrastructure’s exploration is monopolized by INFRAERO (Empresa Brasileira de Infraestrutura Aeroportuaria) but the Federal Constitution allows the airport infrastrucuture’s exploration by the private agents on force from articles 21, XII, c and 175. Besides the Constitution, the Law no. 9.472 from 1997 has created a new kind of exploration: authorization with obligations. Although this Law is for telecommunication sector there is no prohibition for this institute to be applied on the airport infrastructure’s exploration. This work also studied the main forms of airport’s exploration through the State or by private agents. Besides, this work has studied the main functions of the Regulator Authority and Antitrust Authorities to promote the competition among the airports.

This paper explains the reasons for investments on infrastructure by the private sector. Today, there are prisons, water supply, roads, airports and other activities that request a high investment managed by the private sector. It can be done through concessions, privatization or public-private partnerships (PPP). About the private investments on airports, ICAO has allowed the less interference by the states at the airport administration. So, this paper proposes to demonstrate that the application of public private partnership at Brazilian airports is worthwhile.

This paper explains two tendencies of air transport: integrations and unbundling. The vertical integration happens on two ways: operational and industrial. The operational vertical integration refers for every service of the operation such as catering, cargo and maintenance. The industrial vertical integration is growing each day because the airlines are looking for acquiring airports and tour operators. On the same direction of the industrial vertical integration, the horizontal integration is also growing because of high costs of the operations. But the newest tendency is the unbundling on air transport. The unbundling gives more transparency on the relationship between the consumers and the airlines and let the airlines improve their profits.

This paper explains the reasons for investments on infrastructure by the private sector. Today, there are prisons, water supply, roads, airports and other activities that request a high investment managed by private sector. It can be done through concessions, privatization or public private partnerships (PPP). About the private investments on airports, ICAO has allowed the less interference by the States at the airport administration. So, this paper is going to propose the application of public private partnership at Rio de Janeiro's airport.

This paper makes a short history of Air Law before explaning how the economic regulation works on air transport and its going to focus on the basic market access rights. The economic regulation on air transport is shared on three kinds of regulation: national, bilateral and multilateral. At the national level, the regulation is organized by a civil aviation authority. This authority is responsible to organize the civil aviation within a State and make international agreements to regulate the market access rights. While the bilateral regulation there is gap to determinate who is the regulation authority. So, it is regulates by the practice. The multilateral regulation has two important authorities - ICAO (International Civil Aviation Organization) and IATA (International Air Transport Association) - that makes the basic rules of regulation to be followed by the States that signed the International Civil Aviation Conference. About the economic regulation of air transport, ICAO stipulates 10 principles. Being the basic market acess rights the main one. The basic market acess rights are responsible to determinate the level international competition within a State through route and traffic and exploration rights by a foreign airline.

Airlines has been suiting for Deep Vein Thrombosis (DVT) onboard of aircrafts. However, airlines can not be always liable for Deep Vein Thrombosis aboard of aircraft.This paper shows that airlines are not liable if they take measures to avoid DVT aboard.