Abstract
Objective:To evaluate the degree of conversion (DC) and depth (extent) of cure of four resin cements (Variolink E, Calibra, NX3 and Variolink N) using Fourier transform infrared (FTIR) and Vickers Micro hardness (MH).Methods:Ten disks (1mmx2mm) of each resin cement were light cured through a ceramic disk for 40 seconds prior to assessment. The ATR spectra of the uncured resin were collected in absorbance mode from 16 scans at 4 wave number resolutions. Degree of conversion was calculated by estimating the changes in peak height ratio of the absorbance intensities of aliphatic C=C peak at 1638 cm-1 and that of an internal standard peak of aromatic C=C at 1608 cm-1 during polymerization. For Vickers microhardness testing 10 disks of each cement specimen was exposed to 100 grams of load for 15 seconds. Three indentations were made 0.5mm apart and an average Vickers micro-hardness (MH) for each specimen. Two way ANOVA and multiple comparison tests were performed to assess data.Results:The highest degree of conversion by peak area was shown by Variolink-Esthetic [light-cure (87.18±2.90%)]; however the lowest was observed in samples of Variolink-N [Dual cure (44.55±4.33%)]. Similarly, Variolink-Esthetic and NX3 cement showed significantly higher MH as compared to other groups.Conclusion:Ivocerin containing Variolink–E cement showed high degree of conversion and extent of polymerization when compared to conventional light and dual cure luting cements.
Highlights
Advancement in resin based dental materials including resin luting cements is at the center of developing predictable adhesive dentistry
Degree of Conversion (DC): The highest degree of conversion by peak area was shown by photopolymerized samples of Variolink-Esthetic [light-cure (87.18±2.90%)], the lowest
The present study was based on the hypothesis that Variolink E having Ivocerin as photo initiator will have better degree of conversion and extent of polymerization to other luting cements(Variolink N, Calibra and NX3)
Summary
Advancement in resin based dental materials including resin luting cements is at the center of developing predictable adhesive dentistry. Properties of resin based cements critical to the success of adhesive restorations include adequate bond strength, low solubility, biocompatibility, color stability, low film thickness and polymerization shrinkage.[1] Resin cements are classified according to the filler type (micro, micro, nano), mode of activation (photo, chemical and dual cure) and bonding mechanism (self-etch and total etch).[2] Resin cements contain different monomers linked together during polymerization reaction. If the conversion of monomer to polymer is maximized the possibility of polymerization shrinkage of the filling material is increased.[6]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.