2014, Number 3
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Rev Cubana Estomatol 2014; 51 (3)
Usefulness of shaping the glide path before using rotary nickel-titanium endodontic files
Nino BJL, Cortés-Rodríguez CJ, Aguilera CMC
Language: Spanish
References: 26
Page: 270-279
PDF size: 211.91 Kb.
ABSTRACT
Introduction: materials, techniques and designs continue to be studied with the
purpose of reducing the incidence of fracture in endodontic instruments. Shaping of
the glide path has been proposed for this end; however, its usefulness has been a
matter of controversy.
Objective: based on the finite element method, carry out a theoretical analysis of
the usefulness of shaping the glide path before using rotary nickel-titanium
endodontic files.
Methods: numerical simulation was performed based on finite element analysis, to
achieve which mathematical models were built of rotary nickel-titanium files S1 and
S2 of the Protaper
™ series. Autodesk
™ Simulation Multiphysics software was used
to program the mechanical properties of the files, as well as a fracture failure limit
of 1270.588 MPa. The torque recommended by the manufacturer was then applied
and the instrument tip fixed into place (without shaping the glide path) with
restrictions on all degrees of freedom.
In order to simulate glide path shaping, restrictions were applied to all degrees of
freedom at a certain distance from the instrument tip, thus simulating that the
instrument tip remained free.
Results: on fixing the file tips, maximum efforts were 1545.77 Mpa for S1 and
1306.47 Mpa for S2. Instrument fracture was observed. When files were fixed at a
distance from the tip, no fracture was observed.
Conclusions: it was theoretically demonstrated that when file tips are prevented
from being caught, fracture is prevented as well, and such catch is avoided by
shaping the glide path. It is therefore concluded that the procedure is useful to
prevent the fracture of rotary nickel-titanium instruments.
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