SciELO - Scientific Electronic Library Online

 
vol.17 issue4Effects of oral environment stabilization procedures on counts of Candida spp. in childrenIn vitro evaluation of human dental enamel surface roughness bleached with 35% carbamide peroxide and submitted to abrasive dentifrice brushing author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Pesquisa Odontológica Brasileira

Print version ISSN 1517-7491

Abstract

PAZINATTO, Flávia Bittencourt; CAMPOS, Bruno Barbosa; COSTA, Leonardo César  and  ATTA, Maria Teresa. Effect of the number of thermocycles on microleakage of resin composite restorations. Pesqui. Odontol. Bras. [online]. 2003, vol.17, n.4, pp. 337-341. ISSN 1517-7491.  http://dx.doi.org/10.1590/S1517-74912003000400008.

Thermocycling simulates, in vitro, thermal changes that occur in the oral cavity. The aim of this study was to evaluate the influence of the number of cycles on microleakage. Class V cavities (1.5 mm deep, 3 mm in height and 3 mm in width) were prepared in bovine teeth, restored with a Single Bond/Z250 restorative system (3M/ESPE) and then divided into five groups of ten teeth each: group 1 was not thermocycled (control group), and groups 2, 3, 4 and 5 were thermocycled 500, 1,000, 2,500 and 5,000 times, respectively (5º-55º ± 2ºC, 15 s dwell time). The teeth were immersed in 0.5% basic fuchsin aqueous solution for 24 h, sectioned and the sections with the highest degree of microleakage were selected, scanned and the extent of dye penetration was measured by the ImageTool program. The results submitted to one-way ANOVA showed no significant differences between the groups (p > 0.05). The averages of microleakage values in millimeters were: group 1 (3.92); group 2 (3.13); group 3 (4.48); group 4 (4.33) and group 5 (3.42). Thus, it was concluded that there is no relation between the increase of the number of cycles and the increase in microleakage.

Keywords : Dental leakage; Composite resins.

        · abstract in Portuguese     · text in English     · pdf in English