Artigo de peri??dico
Surface roughness and volumetric contraction of a Y-TZP ceramic sintered by microwave energy and by resistive heating
Registro en:
2178-6011
04
20
10.14295/bds.2017.v20i4.1481
Autor
BARCHETTA, NAYARA
NANNI, LARISSA
MIRANDA, JEAN
LAZAR, DOLORES
ASSUI, VALTER
SAAVEDRA, GUILHERME
Resumen
Objectives: The aim of this study was to evaluate
a Y-TZP ceramic sintered by a microwave protocol
on volume shrinkage and surface roughness.
Material and Methods: Twenty four (N=24)
Y-TZP discs were fabricated by milling in CAD/
CAM for size standardization. The mean final
dimensions of the specimens were 15 mm X 1.6
mm. Samples were divided into 2 groups (n=12):
conventional resistive heating sintering protocol
(C - Control) and microwave sintering protocol
(MO - experimental). For the characterization
of the specimens, surface roughness (Ra and Rz
parameters) was evaluated with a roughness tester,
and volume shrinkage was measured with a hand
micrometer. Data were statistically evaluated by
Student???s t and Mann-Whitney U tests (??=0.05).
Results: The roughness results were: 0.25 ??m ??
0.02 (Ra) and 2.68 ??m ?? 0.666 (Rz) for the MO
samples; 0.26 ??m ?? 0.04 (Ra) and 2.73 ??m ??
0.461 (Rz) for the C group (Ra: p = 0.19; Rz: p
= 0.81). The shrinkage results was: MO (21.02%
?? 2.70) and C (20.10% ?? 0.52) (p = 0.274).
Conclusion: The conventional and microwave
sintering methods were similar regarding surface
roughness and volume shrinkage of Y-TZP dental
ceramic.