Whitening: is Omnichroma universal composite unchanging? Spectrophotometric evaluation

Abstract

Background: This study aimed to evaluate the color stability of Class V anterior restorations with universal composite after professional bleaching using a spectrophotometer.

Material and methods: Class V cavities were prepared and restored with universal composite in twenty-eight extracted anterior teeth. One week after restoration, color analysis was performed using the spectrophotometer. In-office bleaching was performed. Color analysis was performed 24 hours, 72 hours and 30 days after bleaching. The parameters evaluated were L* values of each tooth and ΔE values between tooth and restoration at different timepoints. Data were analyzed using a statistical software. A P-value ≤0.05 was used to indicate statistical significance of the results.

Results: There was a non-statistically significant but noticeable difference between the L* values in term of tooth bleaching effect. Non-statistically significant differences were found between the L* values and the ΔE values at different timepoints when evaluating the chromatic difference between the tooth surface and the restoration. The ΔE value one week after the restoration is higher than the ΔE values at the following timepoints, therefore the color difference between the restoration and the adjacent tooth decreases with time after bleaching.

Conclusions: Universal Composite was found to be able to match the color of the surrounding tooth even after the bleaching procedure. Key words:Omnichroma, composite, color, spectrophotometer, whitening.

Figure 1

Silicone with dental elements positioned at the optical system of the spectophotometer.

Figure 2

Black cardboard to simulate the low-light conditions of the oral cavity.

Figure 3

Formula.

Figure 4

Images obtained at T1, T2, T3 and T4. Red circle indicates point P1 (restoration color reference), blue circle indicates point P2 (reference for the color of the surrounding tooth). In the right-hand column, the comparison between the L*a*b* values of points P1 and P2, as well as the value of ΔE, can be seen.