Marginal and internal fit of posterior three-unit fixed zirconia dental prostheses fabricated with two different CAD/CAM systems and materials

Clin Oral Investig. 2017 Nov;21(8):2629-2635. doi: 10.1007/s00784-017-2064-8. Epub 2017 Feb 4.


Objectives: The purpose of this in vitro study was to compare the precision of fit of frameworks milled from semi-sintered regular zirconia and high-translucent (HT) zirconia blanks, fabricated with two different CAD/CAM systems.

Material and methods: Three-unit, posterior fixed dental prostheses (FDP) frameworks were fabricated for standardized dies (n = 11) with two different laboratory computer-aided design (CAD)/computer-aided manufacturing (CAM) systems (Cercon/Ceramill). The replica technique was used to evaluate the marginal and internal fit under an optical microscope. Evaluation of the data was performed according to prior studies at a level of significance of 5%.

Results: The systems showed a statistically significant influence on the internal fit of the frameworks (p ≤ 0.001) and on the marginal fit (p < 0.001). The type of material showed no influence on the marginal fit for the Cercon system (p = 0.636) and on the marginal fit (p = 0.064) and the internal fit (p = 0.316) for the Ceramill system, while regular zirconia from Cercon showed higher internal values than HT zirconia (p = 0.016).

Conclusions and clinical relevance: Both investigated systems showed clinically acceptable values within the limitations of this in vitro study. However, one showed less internal accuracy when regular zirconia was used.

Keywords: Computer-aided design/computer-aided manufacturing; Fixed dental prosthesis; High-translucent zirconia; Marginal and internal fit; Pre-sintered zirconia.

MeSH terms

  • Computer-Aided Design*
  • Dental Marginal Adaptation*
  • Dental Materials / chemistry*
  • Denture Design / methods*
  • Denture, Partial, Fixed*
  • In Vitro Techniques
  • Materials Testing
  • Models, Dental
  • Zirconium / chemistry*


  • Dental Materials
  • Zirconium
  • zirconium oxide