Conversion, Polymerization Shrinkage, Heat Generation, and Depth of Cure of Novel Dental Composites

Depth of Cure of Novel Dental Composites


  • Saad Liaqat Khyber Medical University, Peshawar
  • Humaira Jabeen Department of Dental Materials, Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan



Dental composites, polymerization shrinkage, degree of conversion, depth of cure


This study aims to determine the conversion, polymerization shrinkage, heat generation, and depth of cure of novel dental composites, and compare with current commercial composites. Methods: A total of 24 different formulations were tested for their conversion, shrinkage, heat generation, and depth of cure. Conversion was determined by using FTIR. Polymerization shrinkage and heat generation were determined theoretically using conversion, monomer volume fraction, average molecular weight of monomers present in each formulation, and number of methacrylate groups present in each monomer. Depth of cure was determined using the ISO 4049 scraping test.Results: The values obtained in this study for shrinkage, and heat generation were comparable to commercial bulk filled composites Z250, and Gradia. The factors that reduced the shrinkage and heat generation to a greater extent were sample thickness, and CaP addition. The higher shrinkage and heat generation in thin samples can be explained by large number of photons on the top surface. The heat generation is affected by the same variables as that of conversion and shrinkage. The heat generation values for samples using conversions at a thickness of 4 mm were ~ 0.06 kJ/cc, while using 1 mm thickness values gave ~ 0.08 kJ/cc. The reduction in depth of cure with the addition of CaP was ~ 5 %.Conclusion: The relatively higher, or comparable degree of conversion for experimental composites than commercial materials, could indicate their greater suitability for clinical applications. Polymerisation shrinkage, and heat generation are directly related to conversion, and conversion is affected by depth (thickness) of composites More detailed analysis is needed to confirm the ultimate depth of cure of these materials.


Tsitrou E, Kelogrigoris S, Koulaouzidou E, Antoniades-Halvatjoglou M, Koliniotou-Koumpia E, van Noort R. Effect of Extraction Media and Storage Time on the Elution of Monomers from Four Contemporary Resin Composite Materials. Toxicology International. 2014;21(1):89-95.

Tsitrou E, Kelogrigoris S, Koulaouzidou E, Antoniades-Halvatjoglou M, Koliniotou-Koumpia E, van Noort RJTi. Effect of extraction media and storage time on the elution of monomers from four contemporary resin composite materials. 2014;21(1):89.

Schneider LFJ, Cavalcante LM, Silikas N. Shrinkage Stresses Generated during Resin-Composite Applications: A Review. Journal of Dental Biomechanics. 2010;1(1).

Gupta SK, Saxena P, Pant VA, Pant AB. Release and toxicity of dental resin composite. Toxicology International. 2012;19(3):225.

Mante FK, Ozer F, Walter R, Atlas AM, Saleh N, Dietschi D, et al. The current state of adhesive dentistry: a guide for clinical practice. Compend Contin Educ Dent. 2013;9:2-8.

Nanjundasetty J, Nanda S, Panuganti V, Marigowda J. Marginal sealing ability of silorane and methacrylate resin composites in class II cavities: A scanning electron microscopic study2013 November 1, 2013. 503-8 p.

Dejak B, Młotkowski A. A comparison of stresses in molar teeth restored with inlays and direct restorations, including polymerization shrinkage of composite resin and tooth loading during mastication. Dental materials. 2014.

Ergun G, Egilmez F, Yilmaz S. Effect of reduced exposure times on the cytotoxicity of resin luting cements cured by high-power led. Journal of Applied Oral Science. 2011;19(3):286-92.

Emami N, Söderholm KJM. How light irradiance and curing time affect monomer conversion in light‐cured resin composites. European journal of oral sciences. 2003;111(6):536-42.

Kim YK, Grandini S, Ames JM, Gu L-s, Kim SK, Pashley DH, et al. Critical review on methacrylate resin-based root canal sealers. Journal of Endodontics. 2010;36(3):383-99.

Prakki A, Tallury P, Mondelli RFL, Kalachandra S. Influence of additives on the properties of Bis-GMA/Bis-GMA analog comonomers and corresponding copolymers. Dental materials. 2007;23(10):1199-204.

Rizzante FAP, Duque JA, Duarte MAH, Mondelli RFL, Mendonca G, Ishikiriama SK. Polymerization shrinkage, microhardness and depth of cure of bulk fill resin composites. Dental materials journal. 2019;38(3):403-10.

Świderska J, Czech Z, Świderski W, Kowalczyk A. Reducing of on polymerization shrinkage by application of UV curable dental restorative composites. Polish Journal of Chemical Technology. 2014;16(3):51-5.

Ersen KA, Gürbüz Ö, Özcan M. Evaluation of polymerization shrinkage of bulk-fill resin composites using microcomputed tomography. Clinical oral investigations. 2020;24(5):1687-93.

Son S, Roh H-M, Hur B, Kwon Y-H, Park J-K. The effect of resin thickness on polymerization characteristics of silorane-based composite resin. Restorative dentistry & endodontics. 2014;39(4):310-8.

Abbasi M, Moradi Z, Mirzaei M, Kharazifard MJ, Rezaei S. Polymerization shrinkage of five bulk-fill composite resins in comparison with a conventional composite resin. Journal of Dentistry (Tehran, Iran). 2018;15(6):365.

Durand LB, Ruiz‐López J, Perez BG, Ionescu AM, Carrillo‐Pérez F, Ghinea R, et al. Color, lightness, chroma, hue, and translucency adjustment potential of resin composites using CIEDE2000 color difference formula. Journal of Esthetic and Restorative Dentistry. 2021;33(6):836-43.

Kutz M. Applied plastics engineering handbook: processing and materials: William Andrew; 2011.

Alto M, Vieira R, Guimarães JGA, Poskus LT, Silva EMd. Depth of cure of dental composites submitted to different light-curing modes. Journal of Applied Oral Science. 2006;14(2):71-6.

Yue C, Tantbirojn D, Grothe RL, Versluis A, Hodges JS, Feigal RJ. The depth of cure of clear versus opaque sealants as influenced by curing regimens. The Journal of the American Dental Association. 2009;140(3):331-8.

Sa'di Shirshab Thiab QA, Mohammad K, Mahdi AG. The Effect of Shade and Curing Time on Depth of Cure (DOC) in Two Types of Composites, Polymerized with a Halogen Light Cure System. 2009. doi:

Rodriguez A, Yaman P, Dennison J, Garcia D. Effect of Light-Curing Exposure Time, Shade, and Thickness on the Depth of Cure of Bulk Fill Composites. Oper Dent. 2017;42(5):505-13. doi: 10.2341/16-057-L.



DOI: 10.54393/pbmj.v5i1.246
Published: 2022-01-31

How to Cite

Liaqat, S., & Jabeen, H. (2022). Conversion, Polymerization Shrinkage, Heat Generation, and Depth of Cure of Novel Dental Composites: Depth of Cure of Novel Dental Composites. Pakistan BioMedical Journal, 5(1), 79–82.



Original Article


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