Color Stability of Expired Restorative Dental Composite Resins
Journal Title: IOSR Journal of Dental and Medical Sciences (IOSR-JDMS) - Year 2017, Vol 16, Issue 3
Abstract
Although expired dental composites should not be used in practice, limited information on their properties is available. The purpose of this study was to evaluate their color stability. 3 composite resins (ice/SDI, rok/SDI, spectrum/Dentsply) from 15 to 146 months after their expiration date and the same materials 23 to 45 months before their expiration date were used to make round specimens. All specimens were finished and polished and after their initial storage in water of 37oC for 48h, they were immersed in coffee baths simulating 30,60,90,180,360 days of coffee’s staining effect. A mean of three measurements of color parameters in the CIELAB system were taken with a portable colorimeter (ShadeEye/Shiofu) at all periods, and data were analyzed statistically by 2way repeated measures ANOVA at a=0.05. Color difference values (ΔΕ*) between base line and staining periods for the investigated materials were 17.7 to 47.6 for the new materials and 13.3 to 38.2 for the expired materials. Statistical analysis indicated significant differences between staining periods (p<0.05) with all materials, but no significant differences between expired and unexpired materials (p>0.05). Although investigated materials had expired for long, their staining behavior within coffee was similar to unexpired. Differences found among materials and immersion time.
Authors and Affiliations
Spyropoulou Nikolina, Plevritaki Anastasia, Masouras Konstantinos, Lagouvardos Panagiotis
Jodhpur disease (Primary acquired gastric outlet obstruction in infancy and childhood): A rare case
Jodhpur disease (Primary acquired gastric outlet obstruction in infancy and childhood) is a rare clinical entity causing symptoms of gastric outlet obstruction. This disease was first described in 1997 in Jodhpur, India....
A Study of Spontaneous Bacterial Peritonitis in Cirrhosis of Liver with Ascites with Special Reference to Serial Ascitic Fluid Cell Count as Prognostic Marker
Aim: To study clinical features and prognostic significance of various clinical, biochemical parameters and serial ascitic fluid cell count in SBP.. Study design: Prospective, observational, single centre, non-blind (ope...
“Risk Factors of Neonatal Sepsis: A Study in a Tertiary Care Paediatric Hospital, Dhaka, Bangladesh”
Neonatal sepsis is invasive infection, usually bacterial, occurring during the neonatal period. Signs are multiple, nonspecific, and include diminished spontaneous activity, less vigorous sucking, apnea, bradycardia, tem...
A Study on Prevalence of Thyroid Function Disorders Amongst The Population of Barpeta District, Assam.
Introduction and objectives -Thyroid diseases are amongst the commonest endocrine disorders worldwide. India too is no exception. In India sub Himalayan belt extending from Kashmir to Assam is well a recognized area of e...
Effect of Pranayama on Depression Score and Physical Fitness Index In Pre & Post Menstrual Phases In Young Females
INTRODUCTION- Premenstrual syndrome(PMS) also called Premenstrual tension(PMT) refers to cyclic recurrence of a combination of distressing physical, psychological or behavioral changes during the luteal phase of menstrua...