Comparative Study of Marginal Gap Among Zirconium Dioxide, Poly Ethyl Ethyl Ketone and Porcelain Fused to Metal Implant Supported Crowns


  • Bassam K. Amin Department of Conservative Dentistry, College of Dentistry, Hawler Medical University, Erbil, Kurdistan Region, Iraq. Author



Marginal Gap, CAD/CAM, Implant supported crowns


Objective: Lifetime and clinical success of implant-supported crown are critically affected by the marginal gap. Marginal misfit may lead to microleakage, cement dissolution accumulation of bacteria, food, and oral debris, potentially causing gingival inflammation and peri-implantitis. The objective of this in vitro study was to compare the marginal gap of crowns made from three different materials.

Methods: A shouldered implant abutment was screwed to implant analog and scanned. Computer Aided Design-Computer Aided Manufacturing ( CAD/CAM ) was used to design crown. Zirconium dioxide, Poly ethyl ethyl ketone and porcelain fused to metal were used as materials to fabricate six crowns from each one respectively. Marginal gaps were measured by stereomicroscope at five points for all samples, measurements were recorded using Adobe Photoshop CC 2017 software, and the data were statistically analyzed and subjected to one-way ANOVA and Scheffe post hoc tests (p = 0.05). 

Results: Mean marginal gaps of Zirconia crown were (786 +/- 794 μm) and for porcelain fused to metal were (883+/- 371μm), both groups were significantly different from Poly Ethyl ethyl ketone (2000 +/-1026 μm) group, but there was no significant difference between Zirconium dioxide and porcelain fused to metal.

Conclusions: Within the limitations of this study, it was concluded that although the marginal gaps of the studied implant-supported restorations were in the clinically acceptable range, crowns made from Zirconia provide less marginal gap followed by porcelain fused to the metal crown while PEEK material had the largest gap.


Cresti S, Itri A, Rebaudi A, Diaspro A, Salerno M. Microstructure of titanium-cement-lithium disilicate interface in CAD-CAM dental implant crowns: a three-dimensional profilometric analysis. Clin Implant Dent Relat Res. 2015;17 Suppl 1:e97-106.

Att W, Hoischen T, Gerds T, Strub JR. Marginal adaptation of all-ceramic crowns on implant abutments. Clin Implant Dent Relat Res. 2008;10(4):218-25.

Bayramoğlu E, Özkan YK, Yildiz C. Comparison of marginal and internal fit of press-on-metal and conventional ceramic systems for three- and fourunit implant-supported partial fixed dental prostheses: An in vitro study. J Prosthet Dent. 2015;114(1):52-8.

Karl M, Graef F, Wichmann M, Beck N. Microfractures in metal-ceramic and all-ceramic implant-supported fixed dental prostheses caused by superstructure fixation. Dent Mater J. 2012;31(3):338-45.

Kahramanoğlu E, Kulak-Ozkan Y. Marginal and internal adaptation of different superstructure and abutment materials using two different implant systems for five-unit implant-supported fixed partial dentures: an in vitro study. Int J Oral Maxillofac Implants. 2013;28(5):1207-16.

Euán R, Figueras-Álvarez O, Cabratosa-Termes J, Oliver-Parra R. Marginal adaptation of zirconium dioxide copings: influence of the CAD/CAM system and the finish line design. J Prosthet Dent. 2014;112(2):155-62.

Karataşli O, Kursoğlu P, Capa N, Kazazoğlu E. Comparison of the marginal fit of different coping materials and designs produced by computer aided manufacturing systems. Dent Mater J. 2011;30(1):97-102.

Lee KB, Park CW, Kim KH, Kwon TY. Marginal and internal fit of all-ceramic crowns fabricated with two different CAD/CAM systems. Dent Mater J. 2008;27(3):422-6.

Pak HS, Han JS, Lee JB, Kim SH, Yang JH. Influence of porcelain veneering on the marginal fit of Digident and Lava CAD/CAM zirconia ceramic crowns. J Adv Prosthodont. 2010;2(2):33-8.

McLean JW, von Fraunhofer JA. The estimation of cement film thickness by an in vivo technique. Br Dent J. 1971;131(3):107-11.

Bae SY, Park JY, Jeong ID, Kim HY, Kim JH, Kim WC. Three-dimensional analysis of marginal and internal fit of copings fabricated with polyetherketoneketone (PEKK) and zirconia. J Prosthodont Res. 2017 61(2):106-12.

Park JY, Bae SY, Lee JJ, Kim JH, Kim HY, Kim WC. Evaluation of the marginal and internal gaps of three different dental prostheses: comparison of the silicone replica technique and threedimensional superimposition analysis. J Adv Prosthodont. 2017;9(3):159-69.

Bindl A, Mörmann WH. Marginal and internal fit of all-ceramic CAD/CAM crown-copings on chamfer preparations. J Oral Rehabil. 2005;32(6):441-7.

Karl M, Fischer H, Graef F, Wichmann MG, Taylor TD, Heckmann SM. Structural changes in ceramic veneered three-unit implant-supported restorations as a consequence of static and dynamic loading. Dent Mater Off Publ Acad Dent Mater. 2008;24(4):464-70.

Kim KB, Kim JH, Kim WC, Kim HY, Kim JH. Evaluation of the marginal and internal gap of metal-ceramic crown fabricated with a selective laser sintering technology: two- and threedimensional replica techniques. J Adv Prosthodont. 2013;5(2):179-86.






How to Cite

Comparative Study of Marginal Gap Among Zirconium Dioxide, Poly Ethyl Ethyl Ketone and Porcelain Fused to Metal Implant Supported Crowns. (2019). Sulaimani Dental Journal, 6(1), 4.

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