Brazilian gutta-percha points. Part II: thermal properties

Abstract

This study was undertaken to explore the effect of heating on gutta-percha, analyzing the occurrence of endothermic peaks corresponding to the transformation that occurs in the crystalline structure of the polymer during thermal manipulation. This study also sought to determine the temperature at which these peaks occur, causing a transformation from the beta- to the alpha-form, and from the alpha- to the amorphous phase. Eight nonstandardized gutta-percha points commercially available in Brazil (Konne, Tanari, Endopoint, Odous, Dentsply 0.04, Dentsply 0.06, Dentsply TP, Dentsply FM) and pure gutta-percha (control) were analysed using differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The transition temperatures were determined and analysed. With the exception of Dentsply 0.04 and Dentsply 0.06, the majority of the products showed thermal behaviour typical of beta-gutta-percha, with two endothermic peaks, exhibiting two crystalline transformations upon heating from ambient temperature to 130 degrees. Upon cooling and reheating, few samples presented two endothermic peaks. It was concluded that heating dental gutta-percha to 130 degrees C causes changes to its chemical structure which permanently alter its physical properties.

Effectiveness of gutta-percha and Resilon in filling lateral root canals using thermomechanical technique

“…When using thermomechanical techniques for root canal filling, it is important to assess the properties of gutta-percha at high temperatures [19][20][21] . The thermoplasticity of gutta-percha depends on their chemical composition 19,22,23 and is influenced by the thermal changes induced during the manufacturing process and during their use 20,22 . Many studies have evaluated several endodontic techniques for their ability to fill a root canal and its irregularities 10,14,16,17 .…”

Um material alternativo à base de SBS para substituir a guta percha no tratamento endodôntico

“…Até hoje, a guta percha é a substância obturadora mais utilizada na recuperação do sistema de canais radiculares [3][4][5][6][7][8][9] . Trata-se de um polímero natural, obtido pela coagulação do látex de algumas poucas espécies de árvores da família das Sapotáceas, do gênero Palaquium, das espécies Mimusops balata e Mimusops huberi, existentes principalmente na Sumatra, Filipinas e Malásia [10][11][12][13][14][15] . O principal componente presente no látex é o polímero poli-trans-isopreno, entretanto, o isômero cis pode estar presente em menor proporção [3][4][5][6][7]9,10,[12][13][14][15][16] .…”

“…Trata-se de um polímero natural, obtido pela coagulação do látex de algumas poucas espécies de árvores da família das Sapotáceas, do gênero Palaquium, das espécies Mimusops balata e Mimusops huberi, existentes principalmente na Sumatra, Filipinas e Malásia [10][11][12][13][14][15] . O principal componente presente no látex é o polímero poli-trans-isopreno, entretanto, o isômero cis pode estar presente em menor proporção [3][4][5][6][7]9,10,[12][13][14][15][16] . Em seu estado natural, a guta percha possui massa molar variando entre 10 4 a 10 6 g.mol -1 [8,11,17,28] .…”

In vitro analysis of thermocompaction time and gutta-percha type on quality of main canal and lateral canals filling

“…In alpha phase, in ambient temperatures, the material is fragile, sticky when heated, adherent and with higher flow than in beta phase. 5 Substance purity can alter its fusion point. [6][7][8] Recently, several new products have employed alpha phase to achieve thermocompaction.…”

“…[6][7][8] Recently, several new products have employed alpha phase to achieve thermocompaction. 5 As the composition of these materials is an industrial secret, both the alpha phase and the wax addition to get a more plastic material are questioned. As an example of these new types of cones, we find TP guttapercha (Dentsply-Maillefer).…”