| Grant number: | 14/08408-1 |
| Support type: | Scholarships in Brazil - Scientific Initiation |
| Effective date (Start): | July 01, 2014 |
| Effective date (End): | June 30, 2015 |
| Field of knowledge: | Health Sciences - Dentistry - Dental Materials |
| Principal Investigator: | Tarcisio Jose de Arruda Paes Junior |
| Grantee: | Tayná Mendes Inácio de Carvalho |
| Home Institution: | Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil |
Abstract This research has a proposal to evaluate some mechanical characteristics of a heat cured acrylic resins thermo-active in microwave when varies the condition and type of the gypsum used during processing of polymerization method. Will be used as the object of analysis two commercial dental stones: type II, and III and two heat cured acrylic resin (Lucitone and Vipi Wave). The analysis will be performed out under two different conditions: review of the final product acrylic resin as hardness and porosity and on the way how is the heating of the gypsum and acrylic resin during the curing cycles. The idea is to draw a parallel between what occurs during the polymerization itself, with the consequence that translates into the polymerized material. For the evaluation according to the mechanical characteristics will be adopted the same methodology employed in predecessors studies and enshrined in literature. The L2C Group - Lucitone 550 polymerization, microwave , untreated gypsum type II; L2S Group - Lucitone 550 polymerization, microwave , with prior treatment of type II gypsum ( gypsum dissected ) ; V2C Group - Vipi -Wave polymerization, microwave , untreated gypsum type II; V2S Group - Vipi -Wave polymerization, microwave , with prior treatment of type II gypsum ( gypsum dissected ) ; the L3C Group - Lucitone 550 polymerization, microwave , untreated gypsum type III; L3S Group - Lucitone 550 polymerization, microwave , pretreatment of type III gypsum ( gypsum dissected ) ; V3C Group - Vipi -Wave polymerization, microwave , untreated gypsum type III inclusion; V3S Group - Vipi -Wave polymerization, microwave , pretreatment with type III gypsum ( gypsum dissected ). For the assessment of hardness and porosity are prepared three kinds of wax patterns # 7 in the geometric shape of a parallelogram with dimensions respectively of 2,0 x2,0x2,0cm (8cm3), 2,0 x2,0x1,0 (4cm3) and 2,0 x2, 0x0,5 (2cm3). The pre-drying the gypsum was made in a microwave oven at 600W for 10 minutes. After this period, the flasks remained for two hours in an oven and then proceeding to the pressing of the acrylic resin and its polymerization. Then, finishing and polishing of specimens must be performed. The analysis will be done by Vickers microhardness (VHN) test, where in three indentations are made on each specimen and the average value was considered. To evaluate the porosity is primarily made a ranking as to its presence, and for those where they were found possibly a qualitative analysis is done in a stereomicroscope. Regarding the evaluation of gradation material temperature during the polymerization will be employed Technology iButton temperature sensors that allow to capture the information periodically within the resin and gypsum, such that it allows time to establish a temperature ratio as each situation that is present in both groups. The data analysis will be compiled, distributed and comparatively evaluated using the statistical test Analysis of Variance (ANOVA) 5%. | |