The aim of the present study was to evaluate the difference in cyclic fatigue resistance between OneCurve (OC) and OneShape (OS) endodontic single-file NiTi systems in a severely curved artificial canal. After sample size calculation (α = 0.01; β = 0.20; σ = 20.0; δ = 20.0), 25 OC and 25 OS files were used. An artificial canal with 60° angle and 5-mm radius of curvature was milled in a stainless-steel block reproducing the size and taper of the files used. The test device was electrically heated to maintain the environmental temperature at 37 °C. All files were rotated until fracture; the time to failure was recorded and the number of cycles to fracture (NCF) calculated. The length of the fractured fragments was measured too. Fractographic examination and cross-sectional area calculation were performed by scanning electron microscopy analysis (SEM). Data were statistically analyzed using an independent sample t test. The significance level was set at 0.01. Statistical analysis showed that OC files exhibited significantly greater cyclic fatigue resistance than OS (p < 0.001), with 721 ± 89 NCF and 301 ± 38 NCF, respectively. No significant difference was found in the length of the fractured fragments (p > 0.01). SEM fractographic analysis confirmed that all the scanned samples separated due to cyclic fatigue. Within the limitations of the present study, OC endodontic instruments resisted to cyclic fatigue better than OS. The improved mechanical resistance of OC could be related to new NiTi alloy used for their manufacturing.

In vitro comparison of cyclic fatigue resistance of two rotary single-file endodontic systems: OneCurve versus OneShape

De Biasi, Matteo;Angerame, Daniele
2019-01-01

Abstract

The aim of the present study was to evaluate the difference in cyclic fatigue resistance between OneCurve (OC) and OneShape (OS) endodontic single-file NiTi systems in a severely curved artificial canal. After sample size calculation (α = 0.01; β = 0.20; σ = 20.0; δ = 20.0), 25 OC and 25 OS files were used. An artificial canal with 60° angle and 5-mm radius of curvature was milled in a stainless-steel block reproducing the size and taper of the files used. The test device was electrically heated to maintain the environmental temperature at 37 °C. All files were rotated until fracture; the time to failure was recorded and the number of cycles to fracture (NCF) calculated. The length of the fractured fragments was measured too. Fractographic examination and cross-sectional area calculation were performed by scanning electron microscopy analysis (SEM). Data were statistically analyzed using an independent sample t test. The significance level was set at 0.01. Statistical analysis showed that OC files exhibited significantly greater cyclic fatigue resistance than OS (p < 0.001), with 721 ± 89 NCF and 301 ± 38 NCF, respectively. No significant difference was found in the length of the fractured fragments (p > 0.01). SEM fractographic analysis confirmed that all the scanned samples separated due to cyclic fatigue. Within the limitations of the present study, OC endodontic instruments resisted to cyclic fatigue better than OS. The improved mechanical resistance of OC could be related to new NiTi alloy used for their manufacturing.
File in questo prodotto:
File Dimensione Formato  
Serafin2019_Article_InVitroComparisonOfCyclicFatig.pdf

Accesso chiuso

Tipologia: Documento in Versione Editoriale
Licenza: Copyright Editore
Dimensione 1.32 MB
Formato Adobe PDF
1.32 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
2935662_Serafin2019_Article_InVitroComparisonOfCyclicFatig-PostPrint.pdf

accesso aperto

Descrizione: Post Print VQR3
Tipologia: Bozza finale post-referaggio (post-print)
Licenza: Digital Rights Management non definito
Dimensione 1.64 MB
Formato Adobe PDF
1.64 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11368/2935662
Citazioni
  • ???jsp.display-item.citation.pmc??? 14
  • Scopus 31
  • ???jsp.display-item.citation.isi??? 30
social impact