5,508 research outputs found
Combined Orthodontic and Restorative Minimally Invasive Approach to Diastema and Morphology Management in the Esthetic Area. Clinical Multidisciplinary Case Report with 3-Year Follow-Up
Ceramic laminates are restorations that are bonded using adhesive techniques, which provide for the treatment of the prepared dental elements according to well-defined steps. Adhesive cementation guarantees high predictability and esthetics. Orthodontic treatment is the first choice in patients with a dental misalignment. Patients who have dental element color and shape issues will undergo restorative treatment following orthodontics. Case Report. This clinical report describes a case treated with an interdisciplinary approach (orthodontic and prosthetic) of a patient who presented with diastemas, inversion of dental axes, small clinical crowns, and chromatic imperfections in the anterior maxillary teeth. The esthetic expectations of the patient for the anterior portion of the maxillary anterior teeth have been successfully achieved through orthodontic treatment and the realization of ceramic veneers. An accurate interdisciplinary evaluation of the treatment was necessary for a satisfactory result in the anterior maxillary teeth esthetically compromised in several aspects. Discussion. The modern materials used with the strict protocol of the adhesive procedures allow a minimally invasive, highly esthetic approach with an excellent long-term prognosis. The restorations must reproduce the physiological characteristics of the natural teeth aiming at an excellent biological, biomechanical, functional, and esthetic integration. Many adult patients come to visit with a combination of problems; the esthetic rehabilitation of these cases requires the evaluation of the quantity of gingival exposure, of the gingival architecture, of the size of the clinical crowns, and of the dental position. The ideal treatment of these cases involves an interdisciplinary approach. Prosthodontists, periodontists, orthodontists, and dental technicians must work together because the understanding of the various phases of treatment is fundamental to achieve the desired clinical result
Preventive treatment of post-traumatic dental infraocclusion: study on the knowledge of dental decoronation in a sample of Italian dental students and dentists
AIM: The aim of the present work is to investigate whether dental decoronation is a procedure known by a sample of dental students and Italian dentists. Dental decoronation technique is performed in order to mitigate the outcomes which may occur after a delayed tooth replantation.MATERIALS AND METHODS: A cognitive survey about the knowledge of the dental decoronation technique was carried on two groups: a sample of 120 dental students (5th year of dental school), from University of Cagliari, Sassari and of Chieti-Pescara (60 males and 60 females), and a group which involved 200 Italian dentists (age comprised between 25 and 45, 130 females and 70 males) enrolled at pedodontics and orthodontics Masters and CE courses (University of Roma Sapienza, Chieti- Pescara, Cagliari). The latter group's main field of work was paediatric dentistry and orthodontics, two dental specialties often involved in treating Traumatic dental injuries.RESULTS: Only 20 dentists out of the 200 interviewed answered that they knew this technique and only 5 of them proved to know it and were able to describe it correctly. No students interviewed knew this technique.CONCLUSION: It is apparent from the results of this survey that there is very little information about the dental decoronation technique both during the Degree Course in Dentistry and Post Graduate specialty programmes (Continuing Education Courses and Masters)
Three-dimensional flow instability in a lid-driven isosceles triangular cavity
Linear three-dimensional modal instability of steady laminar two-dimensional states developing in a lid-driven cavity of isosceles triangular cross-section is investigated theoretically and experimentally for the case in which the equal sides form a rectangular corner. An asymmetric steady two-dimensional motion is driven by the steady motion of one of the equal sides. If the side moves away from the rectangular corner, a stationary three-dimensional instability is found. If the motion is directed towards the corner, the instability is oscillatory. The respective critical Reynolds numbers are identified both theoretically and experimentally. The neutral curves pertinent to the two configurations and the properties of the respective leading eigenmodes are documented and analogies to instabilities in rectangular lid-driven cavities are discussed
Dental injuries in young athletes, a five-year follow-up study
Aim The aim of this study is to produce a clinical therapy protocol for a group of 20 athletes between the ages of 8 and 14, who all suffered traumas affecting hard dental and periodontal tissues. Material and methods This study involves a group of 20 athletes (10 male and 10 female) who had suffered dental traumas of varying severity. In order to collect the data, two classification systems were used: one for hard tissue traumas and another for periodontal lesions. The athletes were subdivided into lesion groups, treated depending on the type of lesions and then followed-up over a period of 5 years. A statistical analysis was carried out to study the association between type of lesions, types of sports and the number of teeth involved. Results We found that recovery time ranged from 3 to 5 days for uncomplicated fractures and up to 14 days for luxations. Only four complications were registered during the follow-up period and these were most likely due to the severity of the trauma. Out of the 20 athletes, 16 had begun and maintained the habit of using mouth protection devices when practicing their sport. The statistical analysis focused on the possible association between the risk levels of a sport and the typical lesions and complications that usually occur. Due to their high frequency, the two types of lesions taken into account in our study were complicated fractures (FP) and luxated/fractured teeth (LF). The average number of teeth involved varied according to the sport's risk level (medium or high) with averages of 1.6 teeth involved for medium-risk sports and 2.0 teeth for high-risk sports. Conclusions What emerged in particular was the regular progress in the recovery time needed for the injuries sustained, with few complications or delays in rehabilitation; we also noted that the numerous athletes who habitually used mouthguards while competing during the recovery period did not suffer any recurrences of injuries or further complications. Regarding the results of our statistical analysis, no association was found between the sport's risk, the types of lesions and the occurrence of complications. In addition, analysis of the average number of teeth involved showed that there is no statistical evidence to reject the hypothesis that the ratios remain the same in the two groups
Management accounting change as a learning process: a longitudinal analysis
Purpose The purpose of this paper is to investigate how a substantial organization gradually builds a management accounting system from scratch, changing its accounting routines by learning processes. The paper uses the experiential learning theory and the concept of learning style to investigate the learning process during management accounting change. The study aims to expand the domain of management accounting change theory to emphasize the learning-related aspects that can constitute it. Design/methodology/approach The paper provides an interpretation of management accounting change based on the model of problem management proposed by Kolb (1983) and the theory of experiential learning (Kolb, 1976, 1984). The study is based on a 14-year longitudinal case study (1994-2007). The case examined can be considered a theory illustration case. Data were obtained from a broad variety of sources including interviews, document analysis and adopting an interventionist approach during the redesign of the costing system. Findings The paper contributes to two important aspects of management accounting change. First, it becomes apparent that the costing information change was not a discrete event but a process of experience and learning conducted through several iterations of trial-and-error loops that extended over the years. Second, the findings reveal that the learning process can alter management accounting system design in a radical or incremental way according to the learning style of the people involved in the process of change. Research limitations/implications Because of the adopted research approach, results could be extended only to other organizations presenting similar characteristics. Several further areas of research are suggested by the findings of this paper. In particular, it would be of interest to investigate the links between learning styles and communication and its effect on management accounting change. Practical implications The paper includes implications for the management of learning during management accounting change, to improve the efficiency and effectiveness of this process. Originality/value This paper is one response to the call for an interdisciplinary research approach to the management accounting change phenomena using a "method theory" taken from the discipline of management to provide an explanation of the change in management accounting. In respect of the previous literature, it provides two main contributions, namely, the proposal of a model useful both to interpret and manage learning processes; the effect of learning style on management accounting routines change
Linear white lesion in the oral mucosa
Two unrelated patients aged 60 and 61 presented with an asymptomatic, white, slightly raised line on the buccal mucosa extending bilaterally from the commissure to the last molar teeth along their occlusal line, involving also the inner lower lip mucosa (Fig 1, A and B). The lesions could not wipe off on scratching. Medical history was unremarkable. Histopathology showed hyperparakeratosis without granular layers and regular acanthosis vacuolated cells in the upper spinous cell layer with some dyskeratotic cells in the absence of dysplasia (Fig 2). Neither inflammatory infiltrate nor bacterial colonies attached to the surface or fungal elements were seen (Fig 3)
Preliminary neutron kinetic. Thermal hydraulic coupled analysis of the ALFRED reactor using PHISICS/RELAP5-3D
The development of a lead-cooled fast reactor (LFR) demonstrator was proposed, mainly in EU, to investigate the feasibility of an industrial size ELFR (European Lead-cooled Fast Reactor). The demonstrator, called ALFRED (Advanced Lead-cooled Fast Reactor European Demonstrator), consists of a pool-type lead-cooled fast reactor, with a nominal thermal power of 300 MWt. This paper aims to verify the capability of the PHISICS/RELAP5-3D coupled approach to simulate transients of such reactor and to evaluate the effects of accidental scenarios relevant for the safety analysis on the system thermal-hydraulics and on the core power spatial evolution. RELAP5-3D©, developed at Idaho National Laboratory (INL), is a thermal-hydraulic system code, validated for a wide range of transient simulations. The code provides the possibility to simulate innovative working fluids (such as lead and lead alloys) and to use a fully integrated multi-dimensional nodalization. In addition, the need to study complex neutronic systems recommended the development of a new kinetic model allowing the calculation with any number of energy groups and also considering the transport for the angular variations. At this purpose, INL developed PHISICS (Parallel and Highly Innovative Simulation for INL Code System) and its coupling methodology with RELAP5-3D. The simulation activity described in this paper has been focused on the safety analysis of ALFRED reactor assuming the occurrence of two unprotected transient scenarios: unprotected loss of flow (ULOF) and unprotected transient overpower (UTOP). At this purpose, a thermal-hydraulic geometrical scheme of the whole reactor has been developed. The models and the outcomes of the calculations are described and discussed in the paper, highlighting the capability of the coupling approach to obtain results consistent with the ones available in the literature
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