Fracture resistance of zirconia-based all-ceramic crowns after bur adjustment.
Eur J Oral Sci
; 125(4): 310-313, 2017 08.
Article
en En
| MEDLINE
| ID: mdl-28597965
ABSTRACT
Intra-oral grinding is often required to optimize occlusion of all-ceramic restorations. The effect of burs of different grit size on the fracture resistance of veneered zirconia crowns was investigated in this study. Forty-eight standardized zirconia copings were produced. The ceramic veneer was designed with a positive ellipsoidal defect on the palatal aspect of the crowns. To simulate adjustment of dental restorations by burs, this palatal defect was removed by use of three different diamond-coated burs with grit sizes 46, 107, or 151 µm (fine, medium, or coarse, respectively). Each different grit size of bur was used to grind 16 crowns. All crowns were then polished and surface roughness was measured. Half of the specimens underwent thermomechanical aging (10,000 thermocycles between 6.5°C and 60°C) and 1.2 million cycles of chewing simulation (F = 108 N). A linear regression model was computed to test the effect of aging and grinding grit size at a level of significance of α = 0.05. Fracture loads increased with decreasing grit size. Grit size and aging had a significant effect on the fracture resistance of the crowns. Use of fine and coarse burs for intra-oral adjustments resulted in different fracture resistance of veneered zirconia crowns. Coarse burs should be avoided in the final stage of grinding before polishing.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Circonio
/
Diseño de Prótesis Dental
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Fracaso de la Restauración Dental
/
Coronas
/
Materiales Dentales
Límite:
Humans
Idioma:
En
Revista:
Eur J Oral Sci
Asunto de la revista:
ODONTOLOGIA
Año:
2017
Tipo del documento:
Article
País de afiliación:
Alemania