Research Article
Does Consistency of Dental Resin-Composites Influence their Resistance to Microleakage?
Samy M. El-safty
Correspondence Address :
Samy M. El-safty
Dental
Biomaterials department
School of dentistry, Tanta University
Tanta, Egypt
Email: drelsafti@yahoo.com
Received on: December 08, 2017, Accepted on: December 15, 2017, Published on: December 22, 2017
Citation: Samy M. El-safty (2017). Does Consistency of Dental Resin-Composites Influence their Resistance to Microleakage?
Copyright: 2017 Samy M. El-safty. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Objective: To investigate the influence of consistency of resin-composite restorative materials on microleakage at the restoration/tooth interface.
Materials and Methods: Class V cavities were prepared on the sound facial surfaces of forty recently extracted first and second molars (4 mm mesiodistally, 2 mm occlusogingivally and 2 mm deep). Cavities were thoroughly cleaned using a water spray for 10 s and then dried using an oil-free air spray for 3-5 s. The forty prepared cavities were then randomly divided into four experimental groups (n = 10); Group A: the cavities were incrementally filled with a conventional nanohybrid resin-composite (FiltekTM Z350 XT, 3M ESPE, St. Paul, MN, USA) applied to the dentin surface without adhesive application. Group B: the cavities were incrementally filled with the conventional nanohybrid resin-composite used in Group A but bonded to the dentin surface through an adhesive application (Single Bond Universal, 3M Deutschland GmbH, Germany). Group C: the cavities were incrementally filled with a flowable resin-composite (Vertise FlowTM, Kerr Corporation Orange, CA, USA) applied to the dentin surface without adhesive application. Group D: the cavities were incrementally filled with the flowable resin-composite used in Group C but bonded to the dentin surface through the adhesive used in group B. After 24 h storage in distilled water, specimens were thermocycled for 500 cycles between 5 and 55 degree C with a dwell time of 1 minute. Specimens were then dried and their root apexes were sealed with small increments of resin-composite. A finger nail polish was applied to all surfaces of the teeth except for the restorations and 1 mm surrounding them. Specimens were then immersed in 1% methylene blue dye for 24 h at room temperature. After 24 h, they were then embedded in a self-curing polymethyl methacrylate (PMMA; Esschem Co., PA, USA) and labelled according to their groups. Each specimen was sectioned longitudinally through the center of the restoration from buccal to lingual surface with an Isomet Precision Saw (Isomet TM 5000, Buehler, Illinois, USA). A stereo-microscope at 25x magnification was employed to determine the extent of dye penetration.
Results: From the data recorded, it was clear that the highest leakage scores were shown by Group A (1.3) followed by Group B and C (0.8 and 0.7, respectively) and the lowest leakage scores were recorded by Group D (0.3).
Conclusions: Cavities restored after adhesive application exhibited lower microleakage scores compared to those restored without adhesive application. The flowable resin-composite used in the study proved higher ability to resist microleakage than the conventional one.
Keywords: Microleakage, Consistency of dental resin-composites, Polymerization contraction stress, Dental Adhesive Systems.