World Journal of Dentistry

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VOLUME 14 , ISSUE 9 ( September, 2023 ) > List of Articles


Comparative Evaluation of the Effect of Bleaching on Fracture Toughness of Universal Nanohybrid Composites

Aakansha Puri, M S Prathap, K Jayaprakash, Jeffy M Kunjemun, Natasha Shetty

Keywords : Bleaching, Fracture toughness, Universal composites

Citation Information : Puri A, Prathap MS, Jayaprakash K, Kunjemun JM, Shetty N. Comparative Evaluation of the Effect of Bleaching on Fracture Toughness of Universal Nanohybrid Composites. World J Dent 2023; 14 (9):766-771.

DOI: 10.5005/jp-journals-10015-2289

License: CC BY-NC 4.0

Published Online: 13-10-2023

Copyright Statement:  Copyright © 2023; The Author(s).


Aim: The study aims to assess the effect of bleaching on the fracture toughness of two nanohybrid composites. Materials and methods: A total of 64 composite specimens were prepared using the single-edge notch method. Specimens were divided into four groups (16 per group). Out of 32 specimens of Tetric® N-Ceram Bulk Fill composite (Ivoclar Vivadent, Schaan, Liechtenstein) and Brilliant™ NG composite (Coltene, Whaledent AG) composites, 16 specimens were control and the remaining 16 were included in the test group. The test specimens were exposed to a Pola office (SDI, Victoria, Australia) bleaching agent. Two sets of applications were done as per the manufacturer's instructions. Specimens were rinsed and stored in distilled water for 1 week. Subsequently, the fracture toughness was evaluated using a universal testing machine. Statistical analysis was done using one-way analysis of variance (ANOVA) for comparison between the four groups. Multiple comparison was done using the Bonferroni multiple comparison test. Results: The mean fracture toughness values were the highest for the Brilliant™ NG composite (control group) and the least for the Tetric® N-Ceram Bulk Fill composite group after bleaching. The fracture toughness values were significantly different between control groups and bleaching groups for both the universal nanohybrid composites tested. Conclusion: In the present study, the bleaching procedure significantly affected the fracture toughness of both tested composites. Tetric® N-Ceram Bulk Fill composite group postbleach showed detrimental changes with the lowest fracture toughness values. Clinical significance: Reduced values of fracture toughness may lead to restoration failure and thus, clinicians must be aware of the detrimental changes that may occur associated with the use of bleaching agents.

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