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Influence of Teeth Preparation Finishing on the Adaptation of Lithium Disilicate Crowns

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ABSTRACT

The polishing step of teeth preparations for crowns is a step often performed, so that there is an increased time during the clinical procedure. The aim of this study is to evaluate the marginal and internal adaptation of all-ceramic CAD/CAM lithium disilicate crowns in polished preparations for crown and nonpolished preparations for crowns. For this purpose, 20 first molars were selected, which were divided into two groups (n = 10) G1, teeth that received surface roughening similar to preparation without polishing, and G2 (control), polished preparations. After the preparations were completed the teeth were scanned (Cerec Bluecam, Sirona, Bensheim, Germany), and the crowns were designed and machined using CAD/CAM technology (Sirona, Bensheim, Germany). The adaptation of the pieces was evaluated using polyvinyl siloxane replicas and stereomicroscope photographs with 70x magnifications. The normality test indicated a nonnormal result, so a Man–Whitney nonparametric test was performed. One out of the 24 measured regions showed a statistically significant difference (p = 0.0494). With this study it can be concluded that crowns fabricated by CAD/CAM technology performed on unpolished preparations are not influenced by the internal marginal adaptation and the ceramic part and are different from polished preparations.

No MeSH data available.


Tooth preparation of Group 2 and Group 1.
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fig1: Tooth preparation of Group 2 and Group 1.

Mentions: Group 2 (Control). Preparation shipped from the factory has not been modified. A preparation was simulated with diamond bur in decreased sequence of particle size, fine (#3131F, KG Sorensen), and extra-fine (#3131FF, KG Sorensen), following the steps of finishing and polishing. Upon completion of the preparations step, the teeth were cleaned with compressed air-water to remove any debris that remained on the surface (Figure 1).


Influence of Teeth Preparation Finishing on the Adaptation of Lithium Disilicate Crowns
Tooth preparation of Group 2 and Group 1.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5382306&req=5

fig1: Tooth preparation of Group 2 and Group 1.
Mentions: Group 2 (Control). Preparation shipped from the factory has not been modified. A preparation was simulated with diamond bur in decreased sequence of particle size, fine (#3131F, KG Sorensen), and extra-fine (#3131FF, KG Sorensen), following the steps of finishing and polishing. Upon completion of the preparations step, the teeth were cleaned with compressed air-water to remove any debris that remained on the surface (Figure 1).

View Article: PubMed Central - PubMed

ABSTRACT

The polishing step of teeth preparations for crowns is a step often performed, so that there is an increased time during the clinical procedure. The aim of this study is to evaluate the marginal and internal adaptation of all-ceramic CAD/CAM lithium disilicate crowns in polished preparations for crown and nonpolished preparations for crowns. For this purpose, 20 first molars were selected, which were divided into two groups (n = 10) G1, teeth that received surface roughening similar to preparation without polishing, and G2 (control), polished preparations. After the preparations were completed the teeth were scanned (Cerec Bluecam, Sirona, Bensheim, Germany), and the crowns were designed and machined using CAD/CAM technology (Sirona, Bensheim, Germany). The adaptation of the pieces was evaluated using polyvinyl siloxane replicas and stereomicroscope photographs with 70x magnifications. The normality test indicated a nonnormal result, so a Man–Whitney nonparametric test was performed. One out of the 24 measured regions showed a statistically significant difference (p = 0.0494). With this study it can be concluded that crowns fabricated by CAD/CAM technology performed on unpolished preparations are not influenced by the internal marginal adaptation and the ceramic part and are different from polished preparations.

No MeSH data available.