Reliability and failure behavior of CAD-on fixed partial dentures.
Dent Mater
; 32(5): 624-30, 2016 May.
Article
em En
| MEDLINE
| ID: mdl-26897479
ABSTRACT
OBJECTIVES:
To estimate the reliability and failure behavior of fixed partial dentures (FPDs) fabricated using the CAD-on technique.METHODS:
FPDs (n=25) were fabricated using a CAD/CAM system IPS e.max ZirCAD - Crystall./Connect and IPS e.max CAD (Ivoclar). The restoration type ("three-unit bridge") and design method ("multilayer") based on Biogenerics were used. Framework and porcelain structures were united using a fusion ceramic (Crystall./Connect, Ivoclar). Mechanical fatigue was tested in a servohydraulic load frame machine at a cyclic loading (frequency 2Hz; load ratio 0.1). Based on previous data from specimens tested in fast fracture, three different stress profiles were used. The lifetime data were analyzed using an inverse power law-Weibull cumulative damage model (ALTA PRO, Reliasoft). All failed specimens were examined under a field emission scanning electron microscope.RESULTS:
Porcelain chipping was the predominant (60%) mode of failure for FPDs tested in fast fracture and connector failure was predominant (67%) under fatigue. For fast fracture data, the Weibull modulus (ß) of FPDs was 7.8 combining the two failure modes. When chipping and connector fracture data were analyzed separately, ß values were 7.9 and 2.9. For the step stress fatigue test, ß values were lower than estimated using fast fracture, being 1.6 for connector fracture and 1.3 for porcelain chipping.SIGNIFICANCE:
The test method (fast fracture or fatigue) significantly influenced the reliability of FPDs fabricated using the CAD-on technique, but it did not influence their failure behavior.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Falha de Restauração Dentária
/
Prótese Parcial Fixa
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Dent Mater
Assunto da revista:
ODONTOLOGIA
Ano de publicação:
2016
Tipo de documento:
Article