The effect of a fiber reinforced cavity configuration on load bearing capacity and failure mode of endodontically treated molars restored with CAD/CAM resin composite overlay restorations.
J Dent
; 43(9): 1106-1115, 2015 Sep.
Article
in En
| MEDLINE
| ID: mdl-26149065
ABSTRACT
OBJECTIVES:
To evaluate the fracture strength and the mode of failure of endodontically treated molars restored with CAD/CAM overlays with fiber reinforced composite build-up of the pulp chamber.METHODS:
40 Devitalized molars were cut over the CEJ and divided into five groups (n=8). The pulp chamber area was filled with group 0 (control), no resin build-up; group 1, hybrid composite build-up (G-aenial posterior, GC); group 2, as in group 1 but covered with 3 nets of bi-directional E-glass fibers (EverStickNET, Stick Tech Ltd.); group 3, a FRC resin (EverX posterior, GC); group 4, as in group 3 but covered by the bi-directional fibers. The crowns were restored with CAD-CAM composite restorations (Lava Ultimate, 3M ESPE). Maximum fracture loads were recorded in Newton and data were analyzed using Kruskal-Wallis test (p<0.05). Fragments were analyzed using SEM.RESULTS:
The mean static loads in Newton were group 0 2448 (546); group 1 2817 (873); group 2 2128 (952); group 3 2429 (1091); group 4 2577 (833). No significant differences were found between the groups (p>0.05). All specimens fractured in a catastrophic way, under the CEJ. The main crack evolved in the corono-apical direction. In groups 2 and 4 secondary fracture paths with apico-coronal direction were detected close to the bi-directional fibers' layer.CONCLUSIONS:
For the restoration of endodontically treated molars, the incorporation of FRCs did not influence the load-bearing capacity of the tooth-restoration complex. The SEM analysis showed a low ability of the bi-directional fibers net in deviating the fracture but this effect was not sufficient to lead more favorable fracture patterns, over the CEJ. CLINICALSIGNIFICANCE:
The use of FRCs to reinforce the "core" of devitalized molars against vertical fractures under static loads seems useless when the thickness of the CAD/CAM composite overlay restoration is high.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Resins, Synthetic
/
Composite Resins
/
Tooth, Nonvital
/
Dental Restoration Failure
/
Dental Restoration, Permanent
/
Molar
Type of study:
Clinical_trials
Limits:
Humans
Language:
En
Journal:
J Dent
Year:
2015
Document type:
Article