Pre-heating mitigates composite degradation
J. appl. oral sci
; J. appl. oral sci;23(6): 571-579, Nov.-Dec. 2015. graf
Article
em En
| LILACS, BBO
| ID: lil-769823
Biblioteca responsável:
BR1.1
ABSTRACT
ABSTRACT Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey’s tests (α=5%). Results Radiopacity levels were as follows Durafill VS<Z-350<Z-250 (p<0.05). The depth of silver penetration into the composites ranked as follows Durafill VS>Z-350>Z-250 (p<0.05). After storage in water/NaOH, pre-heated specimens presented higher radiopacity values than non-pre-heated specimens (p<0.05). There was a lower penetration of silver in pre-heated specimens (p<0.05). Conclusions Pre-heating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
BBO
/
LILACS
Assunto principal:
Prata
/
Resinas Compostas
/
Temperatura Alta
/
Calefação
Tipo de estudo:
Evaluation_studies
Idioma:
En
Revista:
J. appl. oral sci
Assunto da revista:
ODONTOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Brasil