In vitro color stability of provisional restorative materials.
BACKGROUND
Discoloration of provisional restorations can result in esthetic problems which are critically important in, for example, anterior areas and may compromise the acceptability of the restoration.


OBJECTIVE
The purpose of this study was to investigate the effect of tea on provisional restorative materials.


METHODS
This study was designed to measure the degree of color change of three acrylic resin provisional materials, before and after immersion in artificial saliva and artificial saliva-tea solution for 2 and 4 weeks.


METHODS
Three types of acrylic provisional materials (duralay, tempron, acropars TRP), were studied. Twenty disks (20 ± 0.1 mm by 2 ± 0.05 mm) were fabricated from each material. Specimens were polished with acrylic bur using pumice and diamond polishing paste. Base line color was measured using a spectrophotometer. Ten disks were stored in artificial saliva and 10 were stored in a solution of artificial saliva and tea at room temperature. Color measurements were made after 2 and 4 weeks of immersion.


METHODS
Differences in color changes were compared by two way ANOVA, across the six groups, followed by a Turkey-Kramer's multiple comparison test.


RESULTS
For specimens immersed in artificial saliva, the color change of methyl methacrylate materials; duralay (ΔE=4.94) and tempron (ΔE=6.54), was significantly more than butyl methacrylate material; acropars (ΔE=4.10). After immersion in an artificial saliva- tea solution, tempron exhibited less color change (ΔE=8.50) compared to duralay (ΔE=10.93) and acropars (ΔE=15.64).


CONCLUSIONS
Color stability of methyl methacrylate is higher than butyl methacrylates so if provisional materials are used for extended periods of time; tempron is preferred.
Department of Prosthodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Hamid
H
Jalali
Hassan
H
Dorriz
Farzaneh
F
Hoseinkhezri
S F
SF
Emadian Razavi
D000180:Acrylic Resins / Q000737:chemistry*; D003116:Color; D003764:Dental Materials / Q000737:chemistry*; D003775:Dental Polishing / Q000379:methods; D003794:Dental Restoration, Temporary; D018130:Diamond / Q000737:chemistry; D006801:Humans; D007101:Immersion; D008689:Methacrylates / Q000737:chemistry; D008768:Methylmethacrylates / Q000737:chemistry; D012464:Saliva, Artificial / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D013053:Spectrophotometry / Q000295:instrumentation; D013499:Surface Properties; D013662:Tea; D013696:Temperature; D013997:Time Factors
C584986:Acropars TR; D000180:Acrylic Resins; D003764:Dental Materials; D008689:Methacrylates; D008768:Methylmethacrylates; D012464:Saliva, Artificial; D017640:Silicates; D013662:Tea; C584985:Tempron; C034578:Duralay; D018130:Diamond; C005144:pumice; C016284:butyl methacrylate