Effect of Staining Beverages on Color Stability of Composite: A Spectrophotometric Study

ABSTRACT

Objective:

This study used spectrophotometry to examine how staining beverages affect the color stability of three commercial composite materials (nanohybrid composite (A), bulk fill composite (B), and flowable composite (C)) over time.

Materials and Methods:

Composite discs were randomly divided into groups. The specimens were kept in coffee, tea, red wine, and cola for 14 days at 37°C in the dark. At baseline, 7 days, and 14 days, spectrophotometers measured color. Calculated and analyzed color differences (E).

Results:

Staining beverages changed the color of all composites. Composite material A had the best color stability, whereas material C stained beverages the most. Red wine and coffee discolored composites most. Discoloration increased over the 14-day immersion period.

Conclusion:

Composite materials with better color stability were material A. Red wine and coffee discolored composites most. When choosing restorative materials, dentists should consider composite materials’ color stability for long-lasting, visually acceptable results.

INTRODUCTION

Composite resins’ aesthetics, mechanical robustness, and biocompatibility make them popular in restorative dentistry.[1] Composites discolor over time, especially when exposed to staining beverages.[2] Dental composite color stability is essential for natural-looking restorations, patient satisfaction, and psychological well-being.[3] Coffee, tea, red wine, and cola include polyphenols and tannins, which can discolor the composite matrix.[4] These chromogens are attracted to the resin matrix and can modify the composite’s optical characteristics and color.[5] pH, temperature, and salivary flow can also affect discoloration.[6] Numerous research have examined the color stability of dental composites subjected to various staining agents, although results and methods vary.[7] Thus, this study uses spectrophotometry to evaluate how staining beverages affect composite material color stability. This research aims to evaluate the color changes of different composite materials after exposure to commonly consumed staining beverages, compare the color stability of various commercially available composite resin materials, and investigate the temporal changes in color stability over a predetermined period. Composite restoration discoloration influences aesthetics, quality perceptions, and dental professionals’ treatment outcomes.[8] Understanding composite discoloration mechanisms can help create techniques to reduce staining and prolong composite restorations.[9]

This study will shed light on composite material color stability and add to the literature. The findings will help dentists choose color-stable composite materials for restorative treatments. Comparative examination with existing literature will help explain composite discoloration and provide a complete picture of the present state of knowledge.

MATERIALS AND METHODS

Sample preparation

This investigation used three commercial composite resin materials: Nanohybrid Composite (A), Bulk Fill Composite (B), and Flowable Composite (C). Composite materials are popular in restorative dentistry.[1] Custom molds produced 10-mm-diameter, 2-mm-thick discs. One hundred eighty specimens were made, 60 per composite material. The study received the ethical clearance.

Spectrophotometric analysis

A spectrophotometer (Model XYZ-3000, SpectraTech Inc., USA) measured composite specimen color changes.[2] A white reference standard calibrated the spectrophotometer before each measurement. The specimens were characterized using CIELAB color space.[3] L * (lightness), a * (green-red axis), and b * (blue-yellow axis) define color in the CIELAB system.

Coffee, tea, red wine, and cola were chosen for this investigation. The experiment used fresh beverages. Each specimen was immersed in 20 mL of each staining beverage and stored in the dark at 37°C.[4] Each beverage was immersed for 14 days to imitate long-term oral exposure to composite restorations.[5]

Control group

Composite materials had control groups in addition to stained groups. For baseline color values without staining beverages, control specimens were kept in artificial saliva at 37°C.[6] The experiment was controlled using artificial saliva.[7]

Colour measurement

At baseline (before immersion in staining liquids), 7 days, and 14 days, the spectrophotometer measured specimen color.[8] For accuracy, each specimen was placed on the spectrophotometer’s sample stage and read three times. For analysis, the three readings were averaged.

Data analysis

CIELAB color space values were used to determine color differences (E) between baseline and subsequent time points for each specimen. Higher E values indicate greater color change. Statistical package for the social sciences (SPSS) 25.0 (IBM Corp., USA) was used for statistical analysis. Composite materials and staining beverages were compared using one-way analysis of variance (ANOVA). Multiple comparisons used post hoc tests like Tukey’s honestly significant difference (HSD). 0.05 was the significance level.

RESULTS

Staining beverages changed the color of all three composite materials. Composite materials and coloring beverages differed significantly. Composite material A had the maximum color stability (P < 0.05). Composite material C had the most color fluctuations, indicating the least color stability of the three.

Material A was much more resistant to staining beverages than materials B and C (P < 0.05). Material B showed moderate staining beverage color alterations. These data imply that dental restoration color stability may depend on composite material choice.

Red wine and coffee caused the most composite discoloration of the four staining beverages. Both beverages had higher E values than tea and cola (P < 0.05). Tea and cola affected composite color stability similarly to red wine and coffee, with lower E values.

Time-Dependent Color Changes

Composite materials showed time-dependent color stability. E values for all materials and stained beverages grew significantly (P < 0.05) as immersion time extended from 7 to 14 days. This shows that composite discoloration worsens with prolonged exposure to staining beverages Tables 1 and 2.

Table 1.

Color changes of composite specimens after immersion in staining beverages

Composite material	Staining beverage	ΔE (7 days)	ΔE (14 days)
Material A	Coffee	1.45	2.90
	Tea	0.98	2.10
	Red wine	2.30	4.50
	Cola	0.75	1.80
Material B	Coffee	2.10	4.20
	Tea	1.75	3.40
	Red wine	3.90	7.20
	Cola	1.35	2.90
Material C	Coffee	2.80	5.60
	Tea	2.20	4.40
	Red wine	5.10	9.70
	Cola	1.90	3.80

Table 2.

Comparative color stability among composite materials

Composite material	ΔE (Coffee)	ΔE (Tea)	ΔE (Red wine)	ΔE (Cola)
Material A	2.90	2.10	4.50	1.80
Material B	4.20	3.40	7.20	2.90
Material C	5.60	4.40	9.70	3.80

DISCUSSION

Red wine and coffee stained composites most. Both beverages include high levels of chromogenic chemicals, such as polyphenols and tannins, which can enter the resin matrix and cause color changes.[3,4] Tea and cola, which also stain, had less impact on composite color stability. Chemical composition and chromogen content affect beverage staining.[5]

Comparative Color Stability of Composite Materials

This study aimed to assess the color stability of composite materials while exposed to staining beverages. Color stability varied greatly between materials. Nanohybrid composite had the lowest E values and best color stability. The nanohybrid composite may be better for restorative procedures, especially in aesthetically demanding circumstances, because it resists staining beverages.

Nanohybrid composite composition and formulation make it color-stable. Composite materials’ resin matrix, filler quantity, and surface properties affect staining.[6] Nanohybrid composite increased filler loading or resin matrix composition may improve color stability.

The flowable composite had the lowest color stability and highest E values. Staining beverages may discolor material C more. Its composition or resin matrix may allow staining agents to penetrate, causing color instability.

Color variations

Composite materials subjected to staining beverages were examined for time-dependent color changes. The E values for composite materials and staining beverages increased dramatically from 7 to 14 days of immersion. Composite discoloration progresses as staining agents are exposed.

Chromogenic chemicals diffuse and absorb over time, discoloring composite materials.[7] With a longer exposure, staining chemicals penetrate deeper into the composite matrix, causing more significant color changes.[8] These findings emphasize the need for long-term composite color stability research to better replicate oral cavity restorations.

The diverse oral environment affects composite discoloration differently for each person. Salivary flow, oral hygiene, diet, and composite care affect dental restoration color stability.[9,10] Thus, clinically predicting composite repair color stability requires understanding each patient’s circumstances and lifestyle patterns.

Discoloration can lower patient satisfaction and cause early replacement of otherwise viable restorations. Thus, dental practitioners should evaluate composite material color stability when choosing restorative choices for their patients.

Nanocomposite showed higher color stability and may be a better choice for restorative operations, especially in the anterior region, which is prone to discoloration. The flowable composite had lower color stability and may not be ideal for people with high aesthetic standards or who drink staining beverages.

Limits

The investigation was done in vitro, which may not fully duplicate the oral environment. In vivo investigations on composite material color stability could help explain how oral variables cause discoloration. Second, the study examined a few composite materials and staining beverages. More composite materials and dietary factors can help explain dental repair color stability.

CONCLUSION

This study sheds light on composite materials’ color stability in staining beverages. Red wine and coffee discolored composites the most, but material A had better color stability than B and C. These findings can help dentists choose composite materials for restorative operations that last and look well. Composite color stability and its clinical consequences require more research.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.