Spectrophotometric analysis of clinical factors related to the color of ceramic restorations: A pilot study

doi:10.1016/j.prosdent.2016.12.010

The Journal of Prosthetic Dentistry

Volume 118, Issue 5, November 2017, Pages 611-616

https://doi.org/10.1016/j.prosdent.2016.12.010 Get rights and content

Abstract

Statement of problem

Shade matching natural teeth with ceramic restorations is still an esthetic, clinical challenge.

Purpose

The purpose of this prospective clinical study was to evaluate the influence of color-related factors on the color variation of ceramic restorations based on spectrophotometric analysis.

Material and methods

Color records were obtained from 11 participants who received 38 lithium disilicate restorations. CIELab color coordinates were measured with a spectrophotometer on the ceramic restoration, tooth (baseline), prepared tooth, and luted ceramics. Color variation (ΔE₀₀) was calculated for each variable (luting agent and restoration type, tooth substrate shade, ceramic thickness, and translucency parameters) measured at baseline on the prepared tooth and after cementation of the restorations. Confidence intervals (CI) for the means (95% CI) were calculated, and the ΔE₀₀ values and CIELab individual color coordinates were compared for each pair of variable by using the Student t test or Welch test (α=.05).

Results

Greater color variation values were observed between measurements obtained on the prepared tooth and luted restoration. The lower ΔE₀₀ values were observed over darker tooth substrate measured at baseline and after luting (P=.007).

Conclusions

The 3 conditions evaluated presented clinically visible color differences, highlighting the importance of clinical evaluations on the visual color acceptability limits for restorations, which are usually defined in laboratory studies. The lithium disilicate ceramic showed lower masking ability over darker tooth substrate, whereas the coordinates L*, a*, and b* were cementation-dependent.

Section snippets

Material and Methods

This prospective clinical study evaluated the color difference (ΔE₀₀) and CIELab color coordinates (L*, a*, and b*) of luted ceramic restorations under 3 conditions: baseline tooth versus luted ceramics, baseline tooth versus prepared tooth, and prepared tooth versus luted ceramic. The following pairs of variables were considered in the comparisons: luting agent, a photoactivated resin cement or flowable composite resin; restoration type, a crown or veneer; tooth substrate shade, lighter or

Results

In this pilot study, 11 participants (7 men, 4 women; mean 39.6 ±13.4 years of age) were included, and 38 ceramic restorations were cemented in anterior teeth (25 laminate veneers, 13 crowns). The patients were provided with a minimum of 1 and a maximum of 6 ceramic restorations. No evaluated tooth showed periodontal problems, and 7 prepared teeth had endodontic treatment. All ceramic restorations had thicknesses between 0.7 and 2 mm.

Mean ±standard deviations (SD) and CI for ΔE₀₀ of the 3

Discussion

This clinical study evaluated the influence of ceramic thickness and TP, tooth substrate shade, luting agent, and restoration type on the color variation of luted ceramic. The hypothesis tested was partially accepted because our findings indicate that tooth substrate shade, restoration type, ceramic thickness, and TP were associated with the final optical properties (ΔE₀₀ and CIELab individual color coordinates) of luted ceramic restorations. Nonetheless, the definitive esthetic appearance of

Conclusions

Within the limitations of this pilot clinical study, the following conclusions were drawn:

1.
The 3 conditions evaluated presented clinically visible color differences, highlighting the importance of clinical evaluations on the visual color acceptability limits for restorations, which are usually defined in laboratory studies.
2.
The lithium disilicate ceramic showed lower masking ability over darker tooth substrate, whereas L*, a*, and b* coordinates were cementation-dependent.

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Citation Excerpt :
Feldspar ceramics are widely used for laminate veneers in anterior teeth due to their excellent esthetic properties, although the presence of high content of vitreous phase makes them more fragile than most ceramic systems. In order to strengthen the ceramic and enhance its clinical performance, resin-based agents are used to lute the restorations to dental structures [1,2]. The strengthening effect by adhesive luting has been attributed to infiltration of ceramic porosities and sealing of superficial cracks, leading to a better dissipation of mechanical stresses and lower stress concentration at the ceramic structure [3,4].
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Clinical ResearchSpectrophotometric analysis of clinical factors related to the color of ceramic restorations: A pilot study

Abstract

Statement of problem

Purpose

Material and methods

Results

Conclusions

Section snippets

Material and Methods

Results

Discussion

Conclusions

Dent Clin North Am

J Prosthet Dent

Dent Mater

J Prosthet Dent

J Dent

J Prosthet Dent

J Dent

J Prosthet Dent

J Dent

Lithium disilicate: the restorative material of multiple options

Comp Cont Educ Dent

Dental color matching instruments and systems. Review of clinical and research aspects

J Dent

Spectrophotometric analysis of tooth color reproduction on anterior all-ceramic crowns: part 1: analysis and interpretation of tooth color

J Esthet Rest Dent

Intraoral determination of the tolerance of dentists for perceptibility and acceptability of shade mismatch

J Prosthet Dent

Validation and reliability of visual assessment with a shade guide for tooth-color classification

Oper Dent

The repeatability of digital shade measurement—a clinical study

Clin Oral Investig

Clinical Research
Spectrophotometric analysis of clinical factors related to the color of ceramic restorations: A pilot study