A guta percha é um dos materiais obturadores mais usados nos tratamentos endodônticos. Este polímero é obtido de poucas espécies de árvores do arquipélago malaio. Sua grande desvantagem é que pode degradar com o tempo devido ao envelhecimento e esta degradação pode ser potencializada com aquecimento durante a obturação. Neste trabalho foram desenvolvidos cones de tratamento endodôntico à base de SBS. Os estudos clínicos mostraram que este novo material pode ser utilizado nas técnicas de obturação a frio e a quente. No caso de um retratamento, foram empregados os mesmos solventes para a guta percha. Porém, a grande vantagem é que estes cones de SBS, por apresentarem uma resistência à abrasão inferior à dos cones de guta percha, são mais facilmente removidos da cavidade do dente, preservando, assim, as paredes do mesmo. As curvas de TGA mostraram que o compósito de SBS apresenta temperatura de degradação superior à da guta percha, indicando um material mais estável à temperatura, característica importante para o processo de obturação do dente.

Gutta percha is the most widely used dental material for root canal fillings and has been used for over 100 years. It is obtained from a few species of trees in the Malaio archipelago. The disadvantage of gutta percha is its degradability upon aging which can be enhanced when heat is used during obturation. In this work, dental cones based on SBS were developed. Clinical results showed that the new material can be used in warm as well as in cold obturation techniques. In the case of retreatment the new material was found to be easier and faster to be removed from the canal, thus preserving the teeth walls. The same behavior was observed when a solvent was used. Furthermore, the new material exhibited a higher degradation temperature which is an indication of its higher temperature stability, an important characteristic during the obturation process.

This paper describes the preparation of magnetic copolymer obtained from suspension polymerization of styrene (Sty) and divinylbenzene (DVB) in the presence of iron particles treated and not treated with oleic acid. The magnetic copolymers were characterized according to their morphology, particle size distribution and magnetic properties. The results show that incorporation of iron particles significantly changed the particles’ morphology. All samples presented higher saturation magnetization than the values reported in the literature and the particle size distribution was more monodisperse when the polymerization was conducted with 5%wt of benzoyl peroxide (BPO).