Journal of Prosthetic Dentistry
Research Article| Volume 108, ISSUE 3, P165-172, September 2012

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Qualitative and quantitative three-dimensional accuracy of a single tooth captured by elastomeric impression materials: An in vitro study

  • Oliver Schaefer
    Corresponding author: Dr Oliver Schaefer, Jena University Hospital – Friedrich Schiller University Jena, Center for Dental Medicine, Biomaterials Research Group, An der Alten Post 4, 07740 Jena, GERMANY, Fax: +49-3641–934411
    Senior Scientist, Biomaterials Research Group, Center for Dental Medicine, Jena University Hospital – Friedrich Schiller University Jena, Jena, Germany
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  • Monika Schmidt
    Associate Professor, Policlinic of Prosthetic Dentistry and Material Science, Jena University Hospital – Friedrich Schiller University Jena, Jena, Germany
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  • Roland Goebel
    Senior Scientist, Policlinic of Prosthetic Dentistry and Material Science, Jena University Hospital – Friedrich Schiller University Jena, Jena, Germany
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  • Harald Kuepper
    Professor and Chairman, Policlinic of Prosthetic Dentistry and Material Science, and Managing Director, Center for Dental Medicine, Jena University Hospital – Friedrich Schiller University Jena, Jena, Germany
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      Statement of problem

      The accuracy of impressions has been described in 1 or 2 dimensions, whereas it is most desirable to evaluate the accuracy of impressions spatially, in 3 dimensions.


      The purpose of this study was to demonstrate the accuracy and reproducibility of a 3-dimensional (3-D) approach to assessing impression preciseness and to quantitatively comparing the occlusal correctness of gypsum dies made with different impression materials.

      Material and methods

      By using an aluminum replica of a maxillary molar, single-step dual viscosity impressions were made with 1 polyether/vinyl polysiloxane hybrid material (Identium), 1 vinyl polysiloxane (Panasil), and 1 polyether (Impregum) (n=5). Corresponding dies were made of Type IV gypsum and were optically digitized and aligned to the virtual reference of the aluminum tooth. Accuracy was analyzed by computing mean quadratic deviations between the virtual reference and the gypsum dies, while deviations of the dies among one another determined the reproducibility of the method. The virtual reference was adapted to create 15 occlusal contact points. The percentage of contact points deviating within a ±10µm tolerance limit (PDP10 = Percentage of Deviating Points within ±10µm Tolerance) was set as the index for assessing occlusal accuracy. Visual results for the difference from the reference tooth were displayed with colors, whereas mean deviation values as well as mean PDP10 differences were analyzed with a 1-way ANOVA and Scheffé post hoc comparisons (α=.05).


      Objective characterization of accuracy showed smooth axial surfaces to be undersized, whereas occlusal surfaces were accurate or enlarged when compared to the original tooth. The accuracy of the gypsum replicas ranged between 3 and 6 µm, while reproducibility results varied from 2 to 4 µm. Mean (SD) PDP10-values were: Panasil 91% (±11), Identium 77% (±4) and Impregum 29% (±3). One-way ANOVA detected significant differences among the subjected impression materials (P<.001).


      The accuracy and reproducibility of impressions were determined by 3-D analysis. Results were presented as color images and the newly developed PDP10-index was successfully used to quantify spatial dimensions for complex occlusal anatomy. Impression materials with high PDP10-values were shown to reproduce occlusal dimensions the most accurately.
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        • Balkenhol M
        • Ferger P
        • Wöstmann B
        Dimensional accuracy of 2-stage putty-wash impressions: influence of impression trays and viscosity.
        Int J Prosthodont. 2007; 20: 573-575
        • Cayouette MJ
        • Burgess JO
        • Jones Jr., RE
        • Yuan CH
        Three-dimensional analysis of dual-arch impression trays.
        Quintessence Int. 2003; 34: 189-198
        • Ceyhan JA
        • Johnson GH
        • Lepe X
        The effect of tray selection, viscosity of impression material, and sequence of pour on the accuracy of dies made from dual-arch impressions.
        J Prosthet Dent. 2003; 90: 143-149
        • Kang AH
        • Johnson GH
        • Lepe X
        • Wataha JC
        Accuracy of a reformulated fast-set vinyl polysiloxane impression material using dual-arch trays.
        J Prosthet Dent. 2009; 101: 332-341
        • Kotsiomiti E
        • Tzialla A
        • Hatjivasiliou K
        Accuracy and stability of impression materials subjected to chemical disinfection - a literature review.
        J Oral Rehabil. 2008; 35: 291-299
        • Lu H
        • Nguyen B
        • Powers JM
        Mechanical properties of 3 hydrophilic addition silicone and polyether elastomeric impression materials.
        J Prosthet Dent. 2004; 92: 151-154
        • Ragain JC
        • Grosko ML
        • Raj M
        • Ryan TN
        • Johnston WM
        Detail reproduction, contact angles, and die hardness of elastomeric impression and gypsum die material combinations.
        Int J Prosthodont. 2000; 13: 214-220
        • Wöstmann B
        • Rehmann P
        • Balkenhol M
        Accuracy of impressions obtained with dual-arch trays.
        Int J Prosthodont. 2009; 22: 158-160
        • Johnson GH
        • Mancl LA
        • Schwedhelm ER
        • Verhoef DR
        • Lepe X
        Clinical trial investigating success rates for polyether and vinyl polysiloxane impressions made with full-arch and dual-arch plastic trays.
        J Prosthet Dent. 2010; 103: 13-22
        • Berg JC
        • Johnson GH
        • Lepe X
        • Adan-Plaza S
        Temperature effects on the rheological properties of current polyether and polysiloxane impression materials during setting.
        J Prosthet Dent. 2003; 90: 150-161
        • Balkenhol M
        • Haunschild S
        • Erbe C
        • Wostmann B
        Influence of prolonged setting time on permanent deformation of elastomeric impression materials.
        J Prosthet Dent. 2010; 103: 288-294
        • Wöstmann B
        • Rehmann P
        • Trost D
        • Balkenhol M
        Effect of different retraction and impression techniques on the marginal fit of crowns.
        J Dent. 2008; 36: 508-512
        • Aguilar ML
        • Elias A
        • Vizcarrondo CE
        • Psoter WJ
        Analysis of three-dimensional distortion of two impression materials in the transfer of dental implants.
        J Prosthet Dent. 2010; 103: 202-209
        • Kwon JH
        • Son YH
        • Han CH
        • Kim S
        Accuracy of implant impressions without impression copings: a three-dimensional analysis.
        J Prosthet Dent. 2011; 105: 367-373
        • Johnson GH
        • Lepe X
        • Aw TC
        The effect of surface moisture on detail reproduction of elastomeric impressions.
        J Prosthet Dent. 2003; 90: 354-364
        • Luthardt RG
        • Walter MH
        • Weber A
        • Koch R
        • Rudolph H
        Clinical parameters influencing the accuracy of 1- and 2-stage impressions: a randomized controlled trial.
        Int J Prosthodont. 2008; 21: 322-327
        • German MJ
        • Carrick TE
        • McCabe JF
        Surface detail reproduction of elastomeric impression materials related to rheological properties.
        Dent Mater. 2008; 24: 951-956
        • Rupp F
        • Geis-Gerstorfer J
        Hydrophilicity of unset and set elastomeric impression materials.
        Int J Prosthodont. 2010; 23: 552-554
        • Petrie CS
        • Walker MP
        • O'Mahony AM
        • Spencer P
        Dimensional accuracy and surface detail reproduction of two hydrophilic vinyl polysiloxane impression materials tested under dry, moist, and wet conditions.
        J Prosthet Dent. 2003; 90: 365-372
        • Balkenhol M
        • Wöstmann B
        • Kanehira M
        • Finger WJ
        Shark fin test and impression quality: a correlation analysis.
        J Dent. 2007; 35: 409-415
        • Mandikos MN
        Polyvinyl siloxane impression materials: an update on clinical use.
        Aust Dent J. 1998; 43: 428-434
        • Ender A
        • Mehl A
        Full arch scans: conventional versus digital impressions–an in-vitro study.
        Int J Comput Dent. 2011; 14: 11-21
        • Luthardt RG
        • Loos R
        • Quaas S
        Accuracy of intraoral data acquisition in comparison to the conventional impression.
        Int J Comput Dent. 2005; 8: 283-294
        • Persson AS
        • Oden A
        • Andersson M
        • Sandborgh-Englund G
        Digitization of simulated clinical dental impressions: virtual three-dimensional analysis of exactness.
        Dent Mater. 2009; 25: 929-936
        • American National Standards Institute/American Dental Association
        ANSI/ADA Specification 19/ISO 4823:2000. Dental elastomeric impression materials. ADA, Chicago2004
        • Lepe X
        • Johnson GH
        • Berg JC
        • Aw TC
        Effect of mixing technique on surface characteristics of impression materials.
        J Prosthet Dent. 1998; 79: 495-502
        • Moldovan O
        • Luthardt RG
        • Corcodel N
        • Rudolph H
        Three-dimensional fit of CAD/CAM-made zirconia copings.
        Dent Mater. 2011; 27: 1273-1278
        • Wadhwani CP
        • Johnson GH
        • Lepe X
        • Raigrodski AJ
        Accuracy of newly formulated fast-setting elastomeric impression materials.
        J Prosthet Dent. 2005; 93: 530-539
        • Bomberg TJ
        • Hatch RA
        • Hoffman W
        Impression material thickness in stock and custom trays.
        J Prosthet Dent. 1985; 54: 170-172
        • Valderhaug J
        • Floystrand F
        Dimensional stability of elastomeric impression materials in custom-made and stock trays.
        J Prosthet Dent. 1984; 52: 514-517
        • Kess RS
        • Combe EC
        • Sparks BS
        Effect of surface treatments on the wettability of vinyl polysiloxane impression materials.
        J Prosthet Dent. 2000; 84: 98-102
        • Millar BJ
        • Dunne SM
        • Nesbit M
        A comparison of three wetting agents used to facilitate the pouring of dies.
        J Prosthet Dent. 1995; 74: 341-344
        • Millar BJ
        • Dunne SM
        • Robinson PB
        The effect of a surface wetting agent on void formation in impressions.
        J Prosthet Dent. 1997; 77: 54-56
        • Robinson PB
        • Dunne SM
        • Millar BJ
        An in vitro study of a surface wetting agent for addition reaction silicone impressions.
        J Prosthet Dent. 1994; 71: 390-393
        • Peters MC
        • Delong R
        • Pintado MR
        • Pallesen U
        • Qvist V
        • Douglas WH
        Comparison of two measurement techniques for clinical wear.
        J Dent. 1999; 27: 479-485
        • Türp JC
        • Greene CS
        • Strub JR
        Dental occlusion: a critical reflection on past, present and future concepts.
        J Oral Rehabil. 2008; 35: 446-453
        • Phillips SD
        Report of a special test. NIST test No. 681/280055-10 October 8, 2010.
        (accessed November 11, 2011.)