Influence of Preheating Procedure and Polymerization Modes on Degree of Conversion of Contemporary Resin Composites

Year 2025, , 65 - 70, 20.01.2025

Özge Gizem Yenidünya Ahmet Erdem Nilgün Akgül , Başak Yazkan Mutlu Özcan

https://doi.org/10.17567/currresdentsci.1617446

Abstract

Objective: To evaluate the effects of preheating procedure and polymerization modes on degree of conversion (DC) of resin composites.
Methods: Three different types of composites - a conventional (GrandioSO - [GSO]), a bulkfill (GrandioSO x-tra - [GSX]), and a thermoviscous bulkfill (VisCalor bulk - [VCB]) - were investigated. Three specimens were prepared for each combination of the variables (composite type*preheating procedure*polymerization mode). Photo-polymerization was performed using an LED operated in standard (SM), high power plus (HM), and x-tra power (XM) modes. DC was measured with Fourier Transform Infrared Spectroscopy after 5 min and 24 h post-irradiation. Furthermore, three-way analysis of variance followed by a Tukey test at a significance level of P <.05 were performed to compare the DC values.
Results: Considering the DC values at two post-irradiation time, preheated VCB group polymerized with HM gave the highest DC value, while GSX cured with XM, regardless of the preheating exhibited the lowest one. Preheating application caused a statistically significant increase in the DC values of the VCB*SM, VCB*HM, and GSO*HM groups at both evaluation periods, and the GSX*SM group at 24h post-irradiation. Regarding the polymerization mode, the ranking depending on the significant differences among all preheated composites tested at both time intervals was HM > SM > XM.
Conclusion: Preheating generally exhibited favorable effects on the DC of all tested composites, with the most significant impact observed in VCB. Additionally, polymerization with x-tra power mode is not recommended to achieve a sufficient DC required for clinically acceptable restorations.
Keywords: bulk fill composite; degree of conversion; FTIR; polymerization mode; preheating; thermoviscousity

Keywords

bulk fill composite, degree of conversion, FTIR, polymerization mode, preheating

References

• 1. Garoushi S, Lassila L, Vallittu PK. Impact of fast high-intensity versus conventional light-curing protocol on selected properties of dental composites. Materials. 2021; 14(6): 1381. https://doi.org/10.3390/ ma14061381
• 2. Bolaños-Carmona V, Benavides-Reyes C, González-López S, González-Rodríguez P, Alvarez-Lloret P. Influence of spectroscopic techniques on the estimation of the degree of conversion of bulk-fill composites. Oper Dent. 2020; 45(1): 92-103. https://doi.org/ 10.2341/18-095-L 3. Sadeghyar A, Watts DC, Schedle A. Limited reciprocity in curing efficiency of bulk-fill resin-composites. Dent Mater. 2020; 36(8): 997-1008.https://doi.org/10.1016/j.dental.2020.04.019
• 4. Ilie N, Stark K. Curing behaviour of high-viscosity bulk-fill composites. J Dent. 2014; 42(8): 977-985. http://dx.doi.org/ 10.1016/j.jdent.2014.05.012
• 5. Besegato JF, Jussiani EI, Andrello AC, et al. Effect of light-curing protocols on the mechanical behavior of bulk-fill resin composites. J Mech Behav Biomed Mater. 2019; 90: 381-387. https://doi.org/ 10.1016/j.jmbbm.2018.10.026
• 6. Aung SZ, Takagaki T, Ikeda M, et al. The effect of different light curing units on Vickers microhardness and degree of conversion of flowable resin composites. Dent Mater J. 2021; 40(1): 44-51. https://doi.org/ 10.4012/dmj.2019-353
• 7. Hasanain FA, Nassar HM. Utilizing light cure units: A concise narrative review. Polymers. 2021; 13(10): 1596. https://doi.org/ 10.3390/polym13101596
• 8. Yang J, Silikas N, Watts DC. Pre-heating time and exposure duration: Effects on post-irradiation properties of a thermos-viscous resin-composite. Dent Mater. 2020;36(6):787-793. https://doi.org/ 10.1016/j.dental.2020.03.025
• 9. Fanfoni L, De Biasi M, Antollovich G, Di Lenarda R, Angerame D. Evaluation of degree of conversion, rate of cure, microhardness, depth of cure, and contraction stress of new nanohybrid composites containing pre-polymerized spherical filler. J Mater Sci Mater Med. 2020; 31(12): 1-11. https://doi.org/10.1007/s10856-020-06464-9
• 10. Wang R, Wang Y. Depth-dependence of Degree of Conversion and Microhardness for Dual-cure and Light-cure Composites. Oper Dent. 2020; 45(4): 396-406. https://doi.org/10.2341/19-074-L
• 11. Daugherty MM, Lien W, Mansell MR, Risk DL, Savett DA, Vandewalle KS. Effect of high-intensity curing lights on the polymerization of bulk-fill composites. Dent Mater. 2018; 34(10): 1531-1541. https://doi.org/10.1016/j.dental.2018.06.005
• 12. Jain L, Mehta D, Meena N, Gupta R. Influence of light energy density, composite type, composite thickness, and postcuring phase on degree of conversion of bulk-fill composites. Contemp Clin Dent. 2018; 9(Suppl 1): S147-152. https://doi.org/10.4103/ccd.ccd_169_18
• 13. Delgado AH, Young AM. Methacrylate peak determination and selection recommendations using ATR-FTIR to investigate polymerisation of dental methacrylate mixtures. PLoS One. 2021; 16(6): e0252999. https://doi.org/10.1371/journal.pone.0252999
• 14. Xu T, Li X, Wang H, et al. Polymerization shrinkage kinetics and degree of conversion of resin composites. J Oral Sci. 2020; 62(3): 275-280. https://doi.org/10.2334/josnusd.19-0157
• 15. Lohbauer U, Zinelis S, Rahiotis C, Petschelt A, Eliades G. The effect of resin composite pre-heating on monomer conversion and polymerization shrinkage. Dent Mater. 2009;25(4):514-519. https://doi.org/10.1016/j.dental.2008.10.006
• 16. Modena RA, Sinhoreti MAC, Palin W, Cavalcante LM, Schneider LF. Light and viscosity effects on the curing potential of bulk-fill composites placed in deep cavities. Odontology. 2021; 109(4): 874-883. https://doi.org/10.1007/s10266-021-00614-3
• 17. Yu P, Yap AUJ, Wang XY. Degree of conversion and polymerization shrinkage of bulk-fill resin-based composites. Oper Dent. 2017; 42(1): 82-89. https://doi.org/10.2341/16-027-L
• 18. Lempel E, Őri Z, Kincses D, Lovász BV, Kunsági-Máté S, Szalma J. Degree of conversion and in vitro temperature rise of pulp chamber during polymerization of flowable and sculptable conventional, bulk-fill and short-fibre reinforced resin composites. Dent Mater. 2021; 37(6): 983-997. https://doi.org/10.1016/j.dental.2021.02.013
• 19. Yılmaz B, Bakkal M, Zengin Kurt B. Structural and mechanical analysis of three orthodontic adhesive composites cured with different light units. J Appl Biomater Funct Mater. 2020; 18: 1-8. https://doi.org/ 10.1177/2280800020901716
• 20. Par M, Marovic D, Attin T, Tarle Z, Tauböck TT. Effect of rapid high-intensity light-curing on polymerization shrinkage properties of conventional and bulk-fill composites. J Dent. 2020; 101: 103448. https://doi.org/10.1016/j.jdent.2020.103448
• 21. André CB, Nima G, Sebold M, Giannini M, Price RB. Stability of the light output, oral cavity tip accessibility in posterior region and emission spectrum of light-curing units. Oper Dent. 2018; 43(4): 398-407. https://doi.org/10.2341/17-033-L
• 22. Tauböck TT, Tarle Z, Marovic D, Attin T. Pre-heating of high-viscosity bulk-fill resin composites: effects on shrinkage force and monomer conversion. J Dent. 2015; 43(11): 1358-1364. http://dx.doi.org/ 10.1016/j.jdent.2015.07.014
• 23. Mundim FM, Garcia LDFR, Cruvinel DR, Lima FA, Bachmann L, Pires-de FDCP. Color stability, opacity and degree of conversion of pre-heated composites. J Dent. 2011; 39: e25-e29. https://doi.org/ 10.1016/j.jdent.2010.12.001
• 24. El-Korashy DI. Post-gel shrinkage strain and degree of conversion of preheated resin composite cured using different regimens. Oper Dent. 2010; 35(2): 172-179. https://doi.org/10.2341/09-072-L
• 25. Lopes LCP, Terada RSS, Tsuzuki FM, Giannini M, Hirata R. Heating and preheating of dental restorative materials—a systematic review. Clin Oral Investig. 2020; 24(12): 4225-4235. https://doi.org/10.1007/ s00784-020-03637-2
• 26. Kincses D, Böddi K, Őri Z, et al. Pre-Heating Effect on Monomer Elution and Degree of Conversion of Contemporary and Thermoviscous Bulk-Fill Resin-Based Dental Composites. Polymers. 2021; 13(20): 3599. https://doi.org/10.3390/polym13203599
• 27. Lempel E, Őri Z, Szalma J, et al. Effect of exposure time and pre-heating on the conversion degree of conventional, bulk-fill, fiber reinforced and polyacid-modified resin composites. Dent Mater. 2019; 35(2): 217-228. https://doi.org/10.1016/j.dental.2018.11.017
• 28. Yang J, Silikas N, Watts DC. Pre-heating effects on extrusion force, stickiness and packability of resin-based composite. Dent Mater. 2019; 35(11): 1594-1602. https://doi.org/10.1016/j.dental.2019. 08.101
• 29. Rueggeberg FA, Hashinger DT, Fairhurst CW. Calibration of FTIR conversion analysis of contemporary dental resin composites. Dent Mater. 1990; 6(4): 241-249. https://doi.org/10.1016/S0109-5641(05)80005-3
• 30. Elkaffass AA, Eltoukhy RI, Salwa-Abd-Elraof Elnegoly SH. Influence of preheating on mechanical and surface properties of nanofilled resin composites. J Clin Exp Dent. 2020;12(5):e494-500. https://doi.org/ 10.4317/jced.56469
• 31. Prasanna N, Pallavi Reddy Y, Kavitha S, Lakshmi Narayanan L. Degree of conversion and residual stress of preheated and room-temperature composites. Indian J Dent Res. 2007;18:173-176. https://doi.org/10.4103/0970-9290.35827
• 32. Daronch M, Rueggeberg FA, De Goes MF, Giudici R. Polymerization kinetics of pre-heated composite. J Dent Res. 2006;85(1):38-43. https://doi.org/10.1177/154405910608500106
• 33. Almeida LND, Mendes GAM, Favarão IN, et al. Influence of preheating and post-curing on a novel fiber-reinforced composite post material. Braz Oral Res. 2018; 32:e97. https://doi.org/ 10.1590/1807-3107bor-2018.vol32.0097
• 34. Fróes-Salgado NR, Silva LM, Kawano Y, Francci C, Reis A, Loguercio AD. Composite pre-heating: effects on marginal adaptation, degree of conversion and mechanical properties. Dent Mater. 2010; 26(9): 908-914. https://doi.org/10.1016/j.dental.2010.03.023
• 35. Atria PJ, Sampaio CS, Caceres E, et al. Micro-computed tomography evaluation of volumetric polymerization shrinkage and degree of conversion of composites cured by various light power outputs. Dent Mater J. 2018; 37(1): 33-39. https://doi.org/10.4012/dmj.2016-430