Influence of different fillers on the properties of an experimental vinyl polysiloxane

Abstract The aim of the study was to evaluate the effect of the incorporation of different fillers on an experimental vinyl polysiloxane (VPS) at two different concentrations, 20% and 40%. Different fillers were added to an experimental VPS. The study was developed in two stages: (i) incorporation of fillers in different concentrations: (a) 20 wt% fillers, and (b) 40 wt%. The fillers were added to experimental VPS and mixed with a speed mixer; (ii) characterization of experimental VPS; after the base paste and catalyst paste were mixed, the experimental VPS was used to make specimens specifically for each test, which were stored at 23°C for 24 hours. The tests were designed according to the specific standardization for the analysis of tensile strength, detail reproduction, Shore A hardness, and elastic recovery. For analysis of filler size pattern, scanning electron microscopy at 1500× magnification was used. The aerosil OX-50 40% (AE), and pure aluminum hydroxide 40% (PAH) groups presented the highest tensile strength and Shore A hardness values. However, those were the only groups that did not present continuous detail reproduction of an intersection of 20 μm line. The elastic recovery was not statistically significant. The undesirable characteristics of VPS (lowest Shore A hardness and tensile strength) were observed when it was added to the composition of acrylic polymer (AP) and fiberglass (FG) in both concentrations, 20% and 40%. In groups AE and PAH, agglomerates of nanofillers were shown in SEM micrography, while the other groups presented different shapes and fillers sizes.

Importância da dimensão vertical no restabelecimento estético do sorriso / Importance of vertical dimension on the reestablishment of an aesthetic smile

Este artigo relata o caso clínico de uma paciente insatisfeita com sua aparência devido a desgastes dentários. A paciente apresentava prótese parcial removível superior e inferior, com perda de dimensão vertical, dada por desgastes dentários generalizados posteriores, os quais alteravam a oclusão. O tratamento reabilitador escolhido para o caso foi, primeiramente, a confecção de restaurações indiretas do tipo overlay de cerômeros nos dentes posteroinferiores, facetas cerâmicas nos elementos anterossuperiores e restaurações diretas anteroinferiores. A partir de um planejamento adequado, seguido de um tratamento bem executado, foi possível lançar mão de diferentes técnicas, a fim de proporcionar à paciente o restabelecimento da função e da estética, bem como do equilíbrio fisiológico oclusal...

The purpose of this article was to report the clinical case of an unsatisfied patient with her appearance related to tooth wear. The patient had upper and lower removable partial dentures with loss of vertical dimension, given by generalized posterior tooth wear, which altered her occlusion. The rehabilitative treatment chosen for the case was indirect restorations (overlay) in posterior lower teeth, ceramic veneers in the anterior-upper teeth and direct restorations in the anterior-lower teeth. Through a well planning and a well-executed treatment, it was possible to use different techniques in order to provide patient function, aesthetics and occlusal physiological balance...