Abstract
Introduction
The aim of this study was to investigate the fracture resistance of endodontically
treated and restored permanent mandibular molars with minimally invasive access cavities
subjected to thermocycling and dynamic loading.
Methods
Forty first and second mandibular molars were randomly assigned to 4 groups (n = 10/group) as follows: group 1, control (intact teeth); group 2, traditional access
cavity (TradAC); group 3, conservative access cavity (ConsAC); and group 4, truss
access cavity (TrecAC). After endodontic treatment, teeth were restored with SDR core
(Dentsply Caulk, Milford, DE) and subjected to thermocycling followed by dynamic and
static loading with a multiaxial fatigue testing machine (Instron, Canton, MA). The
maximum load to fracture and pattern of failure (restorable/unrestorable) were recorded.
Data were evaluated with analysis of variance and the Tukey post hoc test for multiple
comparisons.
Results
Fracture resistance of the samples in the control group were higher than those in
the experimental groups (P < .005). TradAC exhibited the least resistance to fracture (P < .005). There was no statistically significant difference in the fracture resistance
of ConsAC and TrecAC (P = .361) Unrestorable fractures were more frequent in the TradAC group compared with
all other groups.
Conclusions
Mandibular molars with ConsAC and TrecAC exhibited superior fracture resistance compared
with TradAC. TradAC had the highest number of unrestorable fractures.
Key Words
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Article info
Publication history
Published online: July 04, 2021
Identification
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© 2021 American Association of Endodontists.
