Stain Resistance of Resin Modified Glass Ionomer Restoratives

Objectives:   This in vitro study evaluated the stain resistance of resin modified glass ionomer (RMGIs) over time when exposed to tea, red wine and coffee.

 

Methods:   Total of sixty disks, twelve per group, were fabricated using shade A2 of each RMGI material (n=60). Groups: 1-RivaLC(SDI), 2- FujiII-LC(GC America) 3- Riva LCHV(SDI), 4-Photac-FilQuickAplicap(3M ESPE), and 5-KetacNano(3M ESPE).  RMGI was dispensed into a 16mm-diameter stainless steel mold, compressed with a mylar strip and glass slide on both sides. Molds were light cured 1min on each side (SDI Radii Plus), and thickness of the disks measured (1.00±0.05mm).  Three samples from each material were randomly assigned to red wine, black tea, coffee or unstained (control) and stored at 37șC in de-ionized water for three days.  Color and opacity were measured (XRite spectrometer) using the contrast ratio, prior to staining procedure. Water was placed between the disk and substrate to obtain good optical contact.  The samples were then transferred to staining solutions and stored at 37șC.   After 4 and 5 days, samples were removed from staining solutions, washed with de-ionized water, and opacity and color were measured.  Between measurements, the samples were transferred to fresh staining solution and stored at 37șC. The changes in opacity and color were analyzed using ANOVA and Multiple Range Test (LSD,95%confidence level, p-value< 0.05).

 

Results:

Table 1	Change in Color (nm) for 2 day stain immersion
Group	Control	Red Wine	Tea	Coffee
1	1.00 ± 0.66 a	9.92 ± 0.11 a	15.46 ± 0.45 a	8.23 ± 1.14 a
2	0.74 ± 0.17 a	5.59 ± 0.44 b	18.63 ± 0.17 b	8.75 ± 0.93 b
3	0.57 ± 0.40 a	7.55 ± 1.09 c	13.72 ± 1.68 c	6.53 ± 2.30 a
4	0.99 ±0.60 a	11.65 ± 1.22 a	19.09 ± 1.45 b	10.40 ± 0.61 c
5	1.56 ± 0.50 a	3.77 ± 0.60 d	9.92 ± 0.70 d	14.13 ± 2.08 c
Values in one column with the same characters are statistically not different
Table 2	Change in Opacity (nm) for 2 day stain immersion
Group	Control	Red Wine	Tea	Coffee
1	0.27 ± 1.33 a	0.92 ± 0.57 a	8.33 ± 0.29 a	2.40 ± 1.92 a
2	-0.13 ± 0.59 b	0.79 ± 1.93 b	16.01 ± 0.90 b	4.56 ± 1.02 b
3	-0.47 ± 1.73 c	3.66 ± 2.01 c	10.18 ± 2.44 c	5.54 ± 1.36 c
4	-1.16 ± 1.56 c	-0.76  ± 3.65 c	13.41 ± 3.83 d	5.09 ± 1.02 d
5	3.21 ± 3.51 d	4.07 ± 1.67 d	10.78 ± 1.45 e	8.46 ± 1.28 e
Values in one column with the same characters are statistically not different.

 

Conclusions:   Staining with beverages affects both color and opacity.  Group-5 behaves differently from other RMGIs, which take up red wine and coffee stains to a similar extent.   Group-5 takes up more coffee stain than red wine.  Clinically, group-5 may be more appropriate for wine and tea drinkers, while the other RMGIs are more appropriate for coffee drinkers.