Abstract
To evaluate the marginal sealing of resin composite restorations subjected to various light-curing protocols, both with and without artificial aging through thermocycling. A comparative, longitudinal in vitro experimental study was performed with 120 bovine teeth distributed across 8 groups. The teeth were treated with different light intensities (650-1200 mW/cm², 800 mW/cm², 1200 mW/cm², 2500-2800 mW/cm²) along with different curing times (15", 20", 10", 3"), as described in the ISO 11405-2015 standard. Thermocycling comprised of 10,000 cycles to replicate one year of intraoral conditions, and microleakage was measured with dye penetration and the Khera and Chan scale (0-3). The majority of samples (41.7%) displayed dye penetration in the middle third of the interface (grade 2). Significant differences were detected among samples with and without thermocycling in the specific groups (p=0.027 and p=0.013), confirming a possible effect of artificial aging. For the highest light intensities (2500-2800 mW/cm²), no significant differences were present (p=0.527), indicating a possible lower effect of thermocycling at these intensities. The results demonstrate that marginal sealing varies by curing protocols and aging processes. Thermocycling affected microleakage with moderate light intensity, while higher intensities and shorter curing times had a reduced effect. These results point to the need for optimizing the curing protocols to provide better long-term durability for the restoration. Further work should examine other variables that may alter marginal sealing.
References
Shawkey M.D., D'Alba L. Interactions between colour-producing mechanisms and their effects on the integumentary colour palette. Philos Trans R Soc Lond B Biol Sci. 2017; 372 (1724): 20160536.
Grewal N., Seth R. Comparative in vivo evaluation of restoring severely mutilated primary anterior teeth with biological post and crown preparation and reinforced composite restoration. J Indian Soc Pedod Prev Dent. 2008; 26 (4): 141-8.
Opdam N.J., van de Sande F.H., Bronkhorst E., Cenci M.S., Bottenberg P., Pallesen U., Gaengler P., Lindberg A., Huysmans M.C., van Dijken J.W. Longevity of posterior composite restorations: a systematic review and meta-analysis. J Dent Res. 2014; 93 (10): 943-9.
Ástvaldsdóttir Á., Dagerhamn J., van Dijken J.W., Naimi-Akbar A., Sandborgh-Englund G., Tranæus S., Nilsson M. Longevity of posterior resin composite restorations in adults-A systematic review. J Dent. 2015; 43 (8): 934-54.
Worthington H.V., Khangura S., Seal K., Mierzwinski-Urban M., Veitz-Keenan A., Sahrmann P., Schmidlin P.R., Davis D., Iheozor-Ejiofor Z., Rasines Alcaraz M.G. Direct composite resin fillings versus amalgam fillings for permanent posterior teeth. Cochrane Database Syst Rev. 2021; 8 (8): CD005620.
Santos A.P., Moreira I.K., Scarpelli A.C., Pordeus I.A., Paiva S.M., Martins C.C. Survival of Adhesive Restorations for Primary Molars: A Systematic Review and Metaanalysis of Clinical Trials. Pediatr Dent. 2016; 38 (5): 370-378.
Chisini L.A., Collares K., Cademartori M.G., de Oliveira L.J.C., Conde M.C.M., Demarco F.F., Corrêa M.B. Restorations in primary teeth: a systematic review on survival and reasons for failures. Int J Paediatr Dent. 2018; 28 (2): 123-139.
Koppolu M., Gogala D., Mathew V.B., Thangala V., Deepthi M., Sasidhar N. Effect of saliva and blood contamination on the bond strength of self-etching adhesive system- An in vitro study. J Conserv Dent. 2012; 15 (3): 270-3.
Cajazeira M.R., De Sabóia T.M., Maia L.C. Influence of the operatory field isolation technique on tooth-colored direct dental restorations. Am J Dent. 2014; 27 (3): 155-9.
Buchalla W., Attin T., Hilgers R.D., Hellwig E. The effect of water storage and light exposure on the color and translucency of a hybrid and a microfilled composite. J Prosthet Dent. 2002 ; 87 (3): 264-70.
Unsal K.A., Karaman E. Effect of Additional Light Curing on Colour Stability of Composite Resins. Int Dent J. 2022 Jun; 72 (3): 346-352.
Demarco F.F., Corrêa M.B., Cenci M.S., Moraes R.R., Opdam N.J. Longevity of posterior composite restorations: not only a matter of materials. Dent Mater. 2012; 28 (1): 87-101.
Van Ende A., De Munck J., Lise D.P., Van Meerbeek B. Bulk-Fill Composites: A Review of the Current Literature. J Adhes Dent. 2017; 19 (2): 95-109.
Jadhav S., Hegde V., Aher G., Fajandar N. Influence of light curing units on failure of directcomposite restorations. J Conserv Dent. 2011; 14 (3): 225-7.
Rueggeberg F.A., Giannini M., Arrais C.A.G., Price R.B.T. Light curing in dentistry and clinical implications: a literature review. Braz Oral Res. 2017 Aug 28; 31 (suppl 1): e61.
Maktabi H., Ibrahim M., Alkhubaizi Q., Weir M., Xu H., Strassler H., Fugolin A.P.P., Pfeifer C.S., Melo M.A.S. Underperforming light curing procedures trigger detrimental irradiance-dependent biofilm response on incrementally placed dental composites. J Dent. 2019; 88: 103110.
Ding L., He D., Zheng S., Zhou X., Li H., Xi Y., Wang X., Sun X. In-vitro and in-vivo comparative studies of treatment effects on enamel demineralization during orthodontic therapy: implications for clinical early-intervention strategy. Clin Oral Investig. 2024; 28 (10): 545.
Jablonski-Momeni A., Lentz J., Jablonski B., Kiesow A., Morawietz M. A comparison between in vitro and randomized in situ models for remineralization of artificial enamel lesions. Sci Rep. 2024; 14 (1): 25295.
Greenlaw R., Way D.C., Galil K.A. An in vitro evaluation of a visible light-cured resin as an alternative to conventional resin bonding systems. Am J Orthod Dentofacial Orthop. 1989; 96 (3): 214-20.
Mavropoulos A., Staudt C.B., Kiliaridis S., Krejci I. Light curing time reduction: in vitro evaluation of new intensive light-emitting diode curing units. Eur J Orthod. 2005; 27 (4): 408-12.
Uusitalo E., Varrela J., Lassila L., Vallittu P.K. Transmission of Curing Light through Moist, Air-Dried, and EDTA Treated Dentine and Enamel. Biomed Res Int. 2016; 2016: 5713962.
Pirca K., Balbín-Sedano G., Romero-Tapia P., Alvitez-Temoche D., Robles G., Mayta-Tovalino F. Remineralizing Effect of Casein Phosphopeptide-Amorphous Calcium Phosphate and Sodium Fluoride on Artificial Tooth Enamel Erosion: An In Vitro Study. J Contemp Dent Pract. 2019; 20 (11): 1254-1259.
Caceres S., Ayala G., Alvítez-Temoche D., Suarez D., Watanabe R., Mayta-Tovalino F. Bond Strength to Microtraction and Nanofiltration Using Ethanol Wet Bonding Technique in Fresh Extracted Teeth: An Ex Vivo Study. J Int Soc Prev Community Dent. 2020; 10 (4): 466-472.

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Copyright (c) 2025 Julia Medina, Lucia Quispe-Tasayco, Hector Orellana-Arauco, Willy Muñoz, Fran Espinoza-Carhuancho, Frank Mayta-Tovalino.