Fracture strength of two designs of pressed lithium-disilicate glass ceramic restorations of endodontically treated teeth :
Date
2012
DOI
Authors
AlAlawi, Maysoon Hashim Amein
Version
OA Version
Citation
Abstract
OBJECTIVE: This study investigated the fracture strength of extracted natural teeth treated endodontically and restored with two different designs of lithiumĀ disilicate glass ceramic restorations: onlays and complete crowns.
Material and methods: Three groups (n=10) of sound extracted maxillary first premolar teeth that were free from caries, previous restorations, and fractures were used in the study. Teeth that received a restoration were treated endodontically by using conventional techniques. Lithium-disilicate glass ceramic restorations (IPS e.max Press; Ivoclar, Liechtenstein) were fabricated with the pressed lost wax technique. Then the teeth randomly were divided randomly into 3 groups. Teeth in group onlay (ON)were restored with an onlay. Teeth in group complete coverage (CC)were restored with a complete crown. The control group (NR) did not receive a restoration (control). After bonding each all restorations, the fracture strength of the teeth was tested in a universal testing machine. The load was applied with a steel ball (diameter 3.9 mm) to the lingual inclines of the buccal cusp, at a 30-degree angle to the long axis of the tooth and with a crosshead speed of 0.5 mm min. Then load to failure was measured in Newtons.
Statistical Analysis: Statistical analysis was performed by using SPSS version 16.0 software (SPSS, Chicago, II, USA). The alpha (type 1) error level was set at 0.05. To investigate differences in fracture resistance among all investigated groups, 1-way ANOVA was computed followed by Tukey HSD post hoc test for multiple comparisons.
RESULTS: The difference between the mean fracture resistance of the unprepared positive control teeth (NR) and those restored with full crown (CR) and onlay (ON) lithium disilicate glass ceramic was found to be statistically not significant (P[less than]0.05).
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Thesis (MSD) --Boston University Institute for Dental Research and Education, Dubai, 2012 (Prosthodontics).
Includes bibliography: leaves 42-29.
Thesis (MSD) --Boston University Institute for Dental Research and Education, Dubai, 2012 (Prosthodontics).
Includes bibliography: leaves 42-29.
License
This work is protected by copyright. Downloading is restricted to the BU community. If you are the author of this work and would like to make it publicly available, please contact open-help@bu.edu.