Sažetak sa skupa
Evaluation of Direct and Indirect Methods of Repairing Fractured
P. Piotrowski
Z. Krysinski
S. Rztowski
Sažetak
INTRODUCTION: The most common technology used in producing a fixed partial denture is firing porcelain to metal. The fracture of veneering material rarely occurs, although it is one of the most striking problems in daily practise.
PURPOSE: The purpose of this study was to evaluate the shear bond strength of composite to porcelain and metal by using two intraoral repair methods: direct and indirect.
MATERIAL AND METHODS: The direct method was performed by using Ceramic Repair System (Ivoclar, Lichtenstein) with and without sandblasting. The indirect method involved Co-Jet system (ESPE,Germany) and Rely X ARC (3M,USA) as luting agents. 180 specimens fabricated with feldspathic porcelain and Ni-Cr alloy
were divided into 3 groups: CR/0 (direct method of repair without sandblasting), CR/S (direct method of repair with sandblasting) and CJ (indirect method based on Co-Jet system). Each of them was divided into 3 subgroups of 20: porcelain (P), porcelain and metal (P/M) and metal (M). The 10 specimens were then subjected to a shear test in a mechanical testing machine at a crosshead speed of
0.5 mm/min. Mode of failure was recorded. Means and standart deviations of loads were calculated.
RESULTS: Tested groups exhibited the following values in megapascals: CR/0-P = 20.36 ± 3.05; CR/0-P/M = 19.45 ± 3.49; CR/0-M = 10.86 ± 4.1; CR/S-P = 18.21 ± 2.62; CR/S-P/M = 19.34 ± 1.76; CR/S-M = 9,54 ± 2.48; CJ-P = 19.85 ± 1.94; CJ-P/M = 19,78 ± 3.60; CJ-M = 13.56 ± 3.82. The mean fractured loads were significantly lower for metal subgroups than for porcelain and porcelain/ metal subgroups.
CONCLUSION: Higher shear bond strength is expected when porcelain was fractured without extensive metal exposure.
Ključne riječi
Hrčak ID:
10243
URI
Datum izdavanja:
15.9.2002.
Posjeta: 1.280 *