An In Vitro Study Of The Staining Resistance Of IPS E.max Press And VITA Mark â…¡ Ceramic

Objective：To evaluate the staining resistance of IPS e.max Press, Vita markⅡmaterials in artificial saliva, coffee，tea and coca-cola．Materials and Methods:20normal color teeth and20IPS e.max Press andVita markⅡspecimens were produced. The specimens and teeth were stored inartificial saliva，coffee，black tea and cola at37±1℃avoiding the light. Thevalues of L*a*b*the specimens and teeth were determined by VITA Easyshadeimmersion at0,7,30,90days.△E, the color difference was calculated by△E=[(a*)2+(b*)2+(△L*)2]1／2.Results:1. A visible color difference was caused for all groups (△E>1.0)afterimmersing some time,which increased with the prolong immersion time. Andafter90days， color difference values of extracted teeth and Vita mark Ⅱimmersing in coffee, black tea and cola, IPS e.max in coffee solution exceed theclinical acceptable level (△E>3.7).2. For extracted teeth, color difference values of all solutions caused wasstatistically significant (P <0.05) immersion90days, the most significant colorchange was caused in black tea (△E=20.63). For IPS e.max Press, there isn’t difference among the different solutions in the same times(P>0.05), but aslightly serious staining was caused in coffee (△E=3.88). For Vita mark Ⅱ,there isn’t difference among the different solutions in the same times(P>0.05),but a slightly serious staining was caused in black tea (△E=5.58).3. After immersing90days, the color difference values of three groups in coffeeand black tea have differences with each other (P <0.05), and extracted teeth>Vita markⅡ> IPS e.max Press.4. The color change of the extracted teeth group shows significantly decrease ofL*and increase of a*and b*. But color change of IPS e.max Press and VitamarkⅡshow the decrease of L*and slightly decrease of a*and b*.Conclusions:1. All materials (extracted teeth, IPS e.max Press,Vita markⅡ)showed color change after immersion in extrinsic staining solusions. The colordifferences increased with the prolong of immersion time.2.Three groups showed different staining resistance according to the materials.IPS e.max Press and Vita markⅡwere more color stable than extracted teeth, ofwhich color stability IPS e.max Press is the best.3. Extracted teeth showed different staining resistance according to the stainingsolusions, For IPS e.m ax Press and Vita mark Ⅱ, there isn’t difference amongthe different solutions in the same times.