Fracture Resistance of Endodontically Treated Teeth Restored with Composite Systems and Polyethylene Fibers: An In Vitro Study
Endodontically treated teeth; Fracture resistance; Fiber-reinforced composite; Ribbond; EverX Posterior.
AuthorsABSTRACTAim: To evaluate and compare the fracture resistance of endodontically treated premolars restored with nano-ceramic composite, nanocomposite, and short fiber-reinforced composite systems combined with woven polyethylene (Ribbond) fiber. Materials and Methods: Forty freshly extracted human single-rooted premolars were included in this in vitro study. Ten intact teeth served as the control group, while thirty teeth underwent endodontic treatment and standardized mesio-occluso-distal cavity preparation. The specimens were randomly divided into four groups (n = 10): Group 1: intact teeth (control); Group 2: nano-ceramic composite (Neo Spectra ST) with Ribbond fiber; Group 3: nanocomposite (Filtek Z350 XT) with Ribbond fiber; and Group 4: short fiber-reinforced composite (EverX Posterior) with Ribbond fiber. All restorations were occlusally capped with Filtek Z250 XT. Specimens were thermocycled, mounted in acrylic blocks, and subjected to compressive loading using a universal testing machine at a crosshead speed of 1 mm/min and a 30° loading angle until fracture occurred. Fracture loads were recorded in Newtons and fracture patterns were evaluated using a dental operating microscope. Results: The control group showed the highest fracture resistance (938.85 ± 91.28 N). Among restored groups, EverX Posterior + Ribbond showed the highest fracture resistance (786.49 ± 68.54 N), followed by Neo Spectra ST + Ribbond and Filtek Z350 XT + Ribbond. Significant differences were observed among groups (p < 0.001). Conclusion: EverX Posterior combined with Ribbond fiber demonstrated superior fracture resistance and favorable fracture patterns, suggesting its potential as a conservative restorative approach for structurally weakened premolars.
INTRODUCTIONThe long-term success of root canal treatment depends not only on effective cleaning, shaping, and obturation of the root canal system but also on the quality of the definitive coronal restoration placed after endodontic therapy. Following endodontic treatment, teeth frequently lose substantial amounts of hard tissue due to caries removal, access cavity preparation, and the removal of existing restorations. This cumulative loss of structural integrity significantly alters the biomechanical behavior of the tooth, reducing its resistance to functional stresses. Consequently, endodontically treated teeth are generally more susceptible to fracture compared with vital teeth, particularly in posterior regions where occlusal forces are greater.1 The structural weakening of endodontically treated teeth necessitates restorative strategies that not only provide an adequate coronal seal but also reinforce the remaining tooth structure. Intracoronal reinforcement techniques aim to redistribute occlusal forces, minimize stress concentration within the remaining dentin, and improve the mechanical stability of weakened teeth. Such reinforcement becomes particularly important in teeth with extensive cavity preparations, especially mesio-occluso-distal (MOD) cavities, where the removal of marginal ridges significantly compromises •••••••••••••••••••••••••••••••• ejprd.org- Published by Riset Publishing Services LLC.
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