title: Comparative Evaluation of Bond Strength and Microleakage of Standard and Expired Composite at Resin-Dentin Interface: Anin vitroStudy.
abstract: BACKGROUND
  Evaluation of bond strength and microleakage caused by polymerization shrinkage provides a screening mechanism and an indication of the potential for the clinical success of composite restorations.
  
  
  OBJECTIVE
  The aim of this study was to determine the effect on shear bond strength and microleakage of standard and expired composites.
  
  
  METHODS
  Selected specimens were etched using 37% phosphoric acid for 15 seconds and were randomly divided into four groups. Group I: Standard composite and bonding agent; group II: Expired composite and bonding agents; group III: Standard composite and expired bonding agent; and group IV: Expired composite and standard bonding agent. Specimens were further subdivided into two subgroups. In subgroup A, specimens were sheared with a universal testing machine, and the results were calculated in MPa; in subgroup B, specimens was sectioned longitudinally and analyzed for leakage (dye penetration) using a stereomicroscope.
  
  
  RESULTS
  The results of the present study showed that acceptable values for bond strength and microleakage were obtained even if one of the components of the dental resin composite is expired.
  
  
  CONCLUSIONS
  In Indian scenario, the expired composite material may provide some assistance in compromised clinical situations. It can be used as an interim restoration and compensate for the high material cost.
  Talreja N, Singla S, Shashikiran ND. Comparative Evaluation of Bond Strength and Microleakage of Standard and Expired Composite at Resin-Dentin Interface: Anin vitroStudy. Int J Clin Pediatr Dent 2017;10(1):1-4.
authors.affiliation: Postgraduate Student, Department of Pedodontics and Preventive Dentistry, People's College of Dental Sciences and Research Centre, People's University, Bhopal, Madhya Pradesh, India.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Talreja
authors.affiliation: Reader, Department of Pedodontics and Preventive Dentistry, People's College of Dental Sciences and Research Centre, People's University, Bhopal, Madhya Pradesh, India.
authors.forename: Shilpy
authors.initials: S
authors.lastname: Singla
authors.affiliation: Professor and Head, Department of Pedodontics and Preventive Dentistry, People's College of Dental Sciences and Research Centre, People's University, Bhopal, Madhya Pradesh, India.
authors.forename: N D
authors.initials: ND
authors.lastname: Shashikiran
keywords: Bond strength; Expired composites; Microleakage.