Fatigue performance of endodontically treated molars restored with different dentin replacement materials

Janka Molnár; Márk Fráter; Tekla Sáry; Gábor Braunitzer; Pekka K Vallittu; Lippo Lassila; Sufyan Garoushi

doi:10.1016/j.dental.2022.02.007

Fatigue performance of endodontically treated molars restored with different dentin replacement materials

Dent Mater. 2022 Apr;38(4):e83-e93. doi: 10.1016/j.dental.2022.02.007. Epub 2022 Feb 26.

Authors

Janka Molnár¹, Márk Fráter¹, Tekla Sáry¹, Gábor Braunitzer², Pekka K Vallittu³, Lippo Lassila⁴, Sufyan Garoushi⁵

Affiliations

¹ Department of Operative and Esthetic Dentistry, Faculty of Dentistry, University of Szeged, Szeged, Hungary.
² dicomLAB Dental Ltd., Szeged, Hungary.
³ Department of Biomaterials Science and Turku Clinical Biomaterials Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland; City of Turku Welfare Division, Oral Health Care, Turku, Finland.
⁴ Department of Biomaterials Science and Turku Clinical Biomaterials Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
⁵ Department of Biomaterials Science and Turku Clinical Biomaterials Center -TCBC, Institute of Dentistry, University of Turku, Turku, Finland. Electronic address: sufgar@utu.fi.

PMID: 35227528
DOI: 10.1016/j.dental.2022.02.007

Abstract

Objectives: The aim was to investigate the fatigue performance of endodontically treated (ET) molars restored by various dentin-replacing materials and material configurations. Moreover, the impact of additional adhesive treatment with glass-ionomer cement (GIC) was evaluated.

Methods: 250 intact molars were collected and randomly distributed into ten groups (n = 25). After endodontic procedure standard Class I cavities were prepared and restored with different direct restorative techniques and dentin-replacing materials. Two-group were restored with either packable or flowable short fiber-reinforced composites (SFRCs). Two-group were restored by experimental fiber-reinforced GIC with and without adhesive treatment. Four-group were restored by conventional and resin-modified GICs with or without adhesive treatment. One-group was restored with a dual-cure composite resin and last group was restored with only conventional composite resin (control). Fatigue-survival was measured for all specimens using a cyclic-loading machine until fracture occurred or a number of 40.000 cycles were achieved. Kaplan-Meyer survival analysis was conducted, followed by pairwise log-rank post hoc comparisons. Fracture mode was then examined by means of optical microscopy and SEM.

Results: Group restored with flowable SFRC showed significantly higher survival (p < 0.05) compared to all of the groups, except for group restored with packable SFRC (p > 0.05). Group restored with fiber-reinforced GIC had significantly (p < 0.05) higher survival rates compared to other commercial GICs. SEM demonstrated change of the fracture line when fracture reached the SFRC layer.

Significance: Direct restoration of Class I in ET molars with the use of SFRCs as dentin-replacing materials demonstrated its ability to reinforce the dental structures and to increase the fatigue resistance in this specific clinical situation.

Keywords: Fatigue survival; Fiber-reinforced glass ionomer cement; Occlusal cavity; Root canal treated molar teeth; Short fiber-reinforced composite.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Composite Resins / chemistry
Dental Stress Analysis
Dentin
Humans
Materials Testing
Molar
Tooth Fractures*
Tooth, Nonvital*

Substances

Composite Resins