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

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.


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Mentions: The device seated on the tooth preparation was stabilized until the setting of the material occurred, as recommended by the manufacturer, that is, 4:30 minutes. After polymerization, excess silicone was removed, and the silicon portion Light Body Regular Set was identified by letters for the mesial, distal, buccal, and palatal surfaces. The groups were identified by a thin layer of the low viscosity materials; that is, Flexitime Correct Flow was applied to the surface for identifying the roughened group, and Virtual Light Body was applied to the other specimens for identifying the polished group (Figure 2).


Influence of Teeth Preparation Finishing on the Adaptation of Lithium Disilicate Crowns
Film capture with light silicone of another color.
© Copyright Policy
Related In: Results  -  Collection

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

fig2: Film capture with light silicone of another color.
Mentions: The device seated on the tooth preparation was stabilized until the setting of the material occurred, as recommended by the manufacturer, that is, 4:30 minutes. After polymerization, excess silicone was removed, and the silicon portion Light Body Regular Set was identified by letters for the mesial, distal, buccal, and palatal surfaces. The groups were identified by a thin layer of the low viscosity materials; that is, Flexitime Correct Flow was applied to the surface for identifying the roughened group, and Virtual Light Body was applied to the other specimens for identifying the polished group (Figure 2).

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.