eISSN: 2299-551X
ISSN: 0011-4553
Journal of Stomatology
Current issue Archive Manuscripts accepted About the journal Editorial board Reviewers Abstracting and indexing Subscription Contact Instructions for authors Ethical standards and procedures
Editorial System
Submit your Manuscript
SCImago Journal & Country Rank
vol. 76
Original paper

Do high-viscosity bulk-fill composites polymerize sufficiently at deep layers?

Firas Saddam Oglah Albaaj
Iqbal Alshalal
Mohammed Kassim Gholam

  1. College of Dentistry, Mustansiriyah University, Baghdad, Iraq
  2. Training and Workshops Center, University of Technology, Baghdad, Iraq
J Stoma 2023; 76, 1: 37-42
Online publish date: 2023/01/11
View full text Get citation
PlumX metrics:
High-viscosity bulk-fill composites may polymerize insufficiently at deep layers after a short curing time. This in-vitro study aimed to estimate and compare the degree of conversion (DC) and micro-hardness (MH), following 20 and 40 seconds photopolymerization of three high-viscosity bulk-fill composites at 2-4 mm depth.

Material and methods
Three new brands of bulk-fill dental composites were selected for this study, including Beautifil-Bulk (Shofu Inc., Kyoto, Japan), Tetric N-Ceram Bulk Fill (Ivoclar Vivadent AG, Schaan, Liechtenstein), and Opus Bulk Fill (FGM, Joinville, SC, Brazil). For each composite, six disc samples located at a 2-4 mm depth were prepared via photopolymerization for 20 (n = 3) or 40 (n = 3) seconds. Each sample was 2 mm thick and 8 mm wide. Following one-hour post-cure, DC and MH assessments were applied using Fourier transform infrared spectroscopy (FTIR) and Vickers MH devices. Data were analyzed using parametric ANOVA and LSD tests.

Values of DC and MH were higher following 40 seconds compared with 20 seconds photopolymerization. However, none of the composites reached the minimum accepted DC (≥ 55%). For both curing times, Tetric N-Ceram showed the highest DC% (42%, 51%), while Beautifil-Bulk had the highest MH values for top (58.2 ± 0.5, 60.0 ± 1.5) and bottom (47.5 ± 3.1, 53.5 ± 1.0) surfaces.

At a 2-4 mm depth and one-hour post-cure, bulk-fill composites showed insufficient DC and low MH values when photopolymerized for 20 or 40 seconds. The extension of curing time to 40 seconds improved the DC and MH values.


bulk-fill composite, composite micro-hardness, composite degree of conversion

Quick links
© 2024 Termedia Sp. z o.o.
Developed by Bentus.