Traumatic injuries in primary dentition and their immediate and long-term consequences: a 10-year retrospective study from the State University of Rio de Janeiro, Brazil.

BACKGROUND/AIM: Dental trauma is a highly prevalent problem worldwide. The aim of this study was to describe characteristics of trauma to anterior primary teeth and its sequelae for primary and successor teeth over a 10-year period of assistance at the paediatric dental traumatology clinic in the State University of Rio de Janeiro, Brazil. MATERIALS AND METHODS: The data were obtained from the dental records of children assisted from 2006 to 2016. Inclusion criteria were trauma to anterior primary teeth; aged <1 to 9 years at the time of trauma; and at least one follow-up appointment. The data concerning traumatized teeth, child's age, soft tissue injuries, types of traumatic dental injuries and sequelae in both dentitions were collected. RESULTS: Of the 1230 dental records, 483 (39.3%) were eligible, consisting of 815 teeth. The mean age at the time of trauma was 37.4 months (239 males and 244 females). The most important characteristics were: tooth 51 was most affected; falls, at home, on a ceramic floor, were the main cause; gingival laceration, enamel fracture and intrusive luxation were the most frequent types of trauma; premature tooth loss of primary teeth and enamel discoloration in their successor were the most frequent sequelae; and injuries in the periodontal tissue were demonstrated as the highest risk for sequelae in successors (OR, 3.798; p< 0.001). CONCLUSIONS: Most traumatic injuries occur in young children, in their home environment. Consequences for the primary teeth were more frequent compared to the permanent successor tooth. Traumatized primary teeth involving periodontal tissue have more chances to result in sequelae to their successor teeth.

Extensions and solutions for nonlinear diffusion equations and random walks.

We investigate a connection between random walks and nonlinear diffusion equations within the framework proposed by Einstein to explain the Brownian motion. We show here how to properly modify that framework in order to handle different physical scenarios. We obtain solutions for nonlinear diffusion equations that emerge from the random walk approach and analyse possible connections with a generalized thermostatistics formalism. Finally, we conclude that fractal and fractional derivatives may emerge in the context of nonlinear diffusion equations, depending on the choice of distribution functions related to the spreading of systems.

Diffusive process on a backbone structure with drift terms.

The effects of an external force on a diffusive process subjected to a backbone structure are investigated by considering the system governed by a Fokker-Planck equation with drift terms. Our results show an anomalous spreading which may present different diffusive regimes connected to anomalous diffusion and stationary states.

Duplication of a permanent maxillary incisor root caused by trauma to the predecessor primary tooth: clinical case report.

AIM: This report describes a permanent maxillary incisor tooth with two roots possibly caused by trauma to the predecessor primary tooth. SUMMARY: Diagnosis, aetiology, clinical implications and endodontic and aesthetic treatment of an incisor tooth with two roots are presented. Diagnosis, early intervention by a multidisciplinary team and clinical and radiographic examination of patients who suffer trauma to primary teeth are of importance to minimize or avoid damage to successor teeth. KEY LEARNING POINTS: • A possible sequelae of trauma to a primary tooth is root duplication in the permanent tooth. • Root duplication is a rare anomaly that has its diagnosis based on the radiographic examination. • Careful diagnosis and follow-up are necessary to prevent future complications related to the successor tooth.

Fokker-Planck equation in a wedge domain: anomalous diffusion and survival probability.

We obtain exact solutions and the survival probability for a Fokker-Planck equation subjected to the two-dimensional wedge domain. We consider a spatial dependence in the diffusion coefficient and the presence of external forces. The results show an anomalous spreading of the solution and, consequently, a nonusual behavior of the survival probability which can be connected to anomalous diffusion.

Fractional diffusion equation in a confined region: surface effects and exact solutions.

Surface effects on a diffusion process governed by a fractional diffusion equation in a confined region with spatial and time dependent boundary conditions are investigated. First, we consider the one-dimensional case with the boundary conditions rho(0,t)=Phi0(t) and rho(a,t)=Phia(t). Subsequently, the two-dimensional case in the cylindrical symmetry with rho(a,theta,t)=Phia(theta,t) and rho(b,theta,t)=Phib(theta,t) is investigated. For these cases, we also obtain exact solutions for an arbitrary initial condition by using the Green's function approach.

General solution of the diffusion equation with a nonlocal diffusive term and a linear force term.

We obtain a formal solution for a large class of diffusion equations with a spatial kernel dependence in the diffusive term. The presence of this kernel represents a nonlocal dependence of the diffusive process and, by a suitable choice, it has the spatial fractional diffusion equations as a particular case. We also consider the presence of a linear external force and source terms. In addition, we show that a rich class of anomalous diffusion, e.g., the Lévy superdiffusion, can be obtained by an appropriated choice of kernel.

[Dengue study in a slum area in Rio de Janeiro: preliminary analysis]. / Estudo do dengue em área urbana favelizada do Rio de Janeiro: considerações iniciais.

This study is part of a program to control and prevent dengue in a slum bordering on the grounds of the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil. The results obtained from a questionnaire and entomological survey called attention to problems pertaining to the information transmitted by public health campaigns and its interpretation, since many practices result from misunderstanding or forgetting preventive messages. Dengue-related data include most frequent vector breeding sites, people's knowledge, and dengue-related habits. The study's conclusions in terms of dengue prevention point to the need for drafting messages not only about ideal preventive practices but also teaching possible solutions: disseminating frequent messages throughout the year and not only seasonally and planning health education to join health professionals and the population in the search for sustainable dengue control alternatives.

Notes on the training of workers in the health sector.

The following notes attempt to contribute to questions on planning, design, and evaluation of training courses for technical personnel in the health sector. The authors analyze and compare trainees' views on their courses and point out issues related to planning, implementation, and some benefits of training for trainees' lives.