ABSTRACT
As próteses parciais removíveis (PPRs) são indicadas para reabilitação, devolvendo a funcionalidade e estética comprometida com a perda dentária. Possuem uma estrutura metálica responsável pela ancoragem dos elementos dentais e sua vida útil pode estar relacionada, dentre outros fatores, a defeitos provenientes das técnicas de fundição. Este estudo teve por objetivo avaliar a frequência e localização da porosidade interna nas estruturas metálicas de PPR em ligas de cobalto-cromo, através de uma análise radiográfica, com aparelho odontológico de consultório, por se tratar de um método eficaz, simples, conservador e de baixo custo. Foram analisadas 60 estruturas metálicas, sendo 37 superiores e 23 inferiores, confeccionadas junto às disciplinas de prótese do curso de Odontologia da Escola Bahiana de Medicina e Saúde Pública (EBMSP), durante o período letivo de 2012.2 a 2013.1. Os resultados mostraram que 50% das peças apresentavam evidências radiográficas de porosidade, distribuídas entre seus componentes. Pode-se concluir que o conector maior das amostras superiores é a área mais propensa a apresentar defeitos internos quando comparado aos retentores e apoios.
The removable partial dentures (RPDs) are indicated for rehabilitation, restoring function and aesthetics compromised due to tooth loss. They have a metal structure responsible for the anchorage of the dental elements and its lifespan may be related, among other factors, to defects resulting from casting techniques. This study aims to assess the frequency and location of internal porosity in the metal structures of PPR in cobalt-chromium alloy, through a radiographic analysis using with dental office machine an effective, simple, conservative and low cost method. Sixty metal structures were evaluated, being 37 upper and 23 lower. These structures were manufactured during the discipline of Prosthesis from the Dentistry Course (Escola Bahiana de Medicina e Saúde Pública) between2012.2 and 2013.1.Results showed that 50% of the items presented radiographic evidence of porosity distributed among its components. It can be concluded that the larger connector of the upper samples is the most susceptible to internal defects when compared to retainers and supports.
Subject(s)
Humans , Dental Materials/chemistry , Porosity , Denture, Partial, Removable , Radiography, Dental/instrumentation , Brazil , Data Interpretation, StatisticalABSTRACT
The objective of this article was to investigate the perception of esthetic changes in the facial profile of bilateral Class II patients treated with the Modified Thurow Appliance for extraoral treatment. Silhouettes were traced of profiles of patients who initially presented a bilateral Class II molar relationship and who, post-treatment, presented molars in a Class I relationship. Three groups were formed: the first composed of patients with maxillary protrusion (SNA >84°), the second with maxillary retrusion (SNA <80°), and the third with a well-positioned maxilla (SNA 80-84°). A panel of 200 lay evaluators judged the profile esthetics by a randomized drawing of the silhouettes. The multiple analysis results showed that the profile esthetic scores for the three positions of the maxilla were greatly influenced by significant interactions with the characteristics (like sex and age) of the evaluators: retrusive maxilla (Score *Age Group, p< 0.001), normal maxilla (Score *Sex, p= 0.024; Score *Age Group,p= 0.050) and protrusive maxilla (Score *Age Group,p< 0.001). It was observed that the profile of Class II patients with protrusion, normal relationship and retrusion of the maxilla, improved in their esthetic post-treatment result; however, the evaluators showed greater satisfaction with the groups of protrusion and normal position of the maxilla. The Modified Thurow Appliance provided significant improvements in the esthetics of the profile of patients who presented protrusion and normal position of the maxilla. However, its use was not the best treatment option for patients with maxillary retrusion.