Resumo

BARROS, Suelen Aline de Lima et al. Dimensional change in gypsum models with fractures and collage with cyanocrylate. RFO UPF [online]. 2014, vol.19, n.1, pp. 44-47. ISSN 1413-4012.

Objective: To assess the dimensional accuracy of gypsum models types III and IV, subjected to several types of fractures and followed by cyanoacrylate bonding. Materials and method: The sample consisted of 80 cast models made from Platinum Zetalabor™ addition silicone dies from a master model in stainless steel, with two abutments. Two groups were formed (n = 40): Group 1 - Gypsum models type III, and Group 2 - Gypsum models type IV. Each group was subdivided by: Control (n = 10) - Gypsum models without fracture; Experimental 1 (n = 10) - Gypsum models bonded with Super Bonder™ cyanoacrylate-based adhesive after fracture in the prosthetic space between two abutments; Experimental 2 (n = 10) - Gypsum models bonded after horizontal fracture in the abutments, simulating fracture occurred during removal of the die model; Experimental 3 (n = 10) - Gypsum models bonded after fracture simulating an accident of fall from a laboratory bench. The sampling units were measured using a digital caliper. Data were processed and subjected to statistical analysis (Shapiro-Wilk test, and Student t test). Results: The gypsum models fractured and bonded with cyanoacrylate showed linear dimensional changes when compared to respective controls. The gypsum models type III from Group 1 behaved differently when compared to gypsum models type IV from the same group. Conclusion: The bonding of abutments in cast models of fixed prosthesis without standardization threatens their dimensional accuracy.

Palavras-chave : Gypsum.; Dental Prosthesis.; Cyanoacrylate..