When it comes to choosing materials for dental restorations, improvements in manufacturing processes of ceramics like zirconia have allowed many dental labs to opt for non-metal solutions with confidence. By combining this with the ongoing integration of CAD/CAM technologies into their workflows, they can now manufacture both esthetic anterior and durable posterior restorations. With patients increasingly demanding natural and long-lasting results, CAD/CAM enables dental labs to fulfill these expectations and create full-contour ceramic restorations, made from materials like high-translucency, multilayered zirconia, that are designed to provide long-term solutions.

Screw-retained CAD/CAM zirconia restorationsZirconia: Achieve natural, long-lasting esthetics

Otherwise known as zirconium dioxide, zirconia has the potential to be processed to possess a tooth-like translucency. This esthetic promise, combined with its strength1 and biocompatibility,2

 have helped to make zirconia a viable, long-lasting solution for dental restorations.

The ability of this material to be built up in a multi-layered manner is what allows for restorations to emulate the translucency and color gradation of natural dentition. Zirconia’s superior level of bending strength and similar fracture toughness, in comparison to other ceramic-based materials, have made it an extremely popular choice in dental labs worldwide.3

This hasn’t always been the case. Early generations of ceramic restorative materials faced issues. They were either too weak or in the case of some newer, high-strength ceramic materials, unable to be processed by conventional technologies and methods.4 To provide patients with restorations that were both functional and visually pleasing, the methods of manufacturing and handling these materials needed to be rethought.

Full-contour zirconiaThe development of dental CAD/CAM technology

The 1983 introduction of the Procera method represented a milestone in dental CAD/CAM technology, as it automated the manufacturing of prosthetic dental components. Developed by Dr. Matts Andersson, the repeatable, high-precision fabrication of individualized dental prosthetics at an industrial scale was now possible.

Nobelpharma – the precursor to Nobel Biocare – acquired Procera in 1988 and, in the following year, released the first-ever ceramic CAD/CAM coping. The ability to provide durable, metal-free restorative solutions that blend naturally with surrounding teeth, once considered to be a nonstarter, suddenly seemed achievable.

Since these early days, dental CAD/CAM tools have continued to advance in both sophistication and acceptance by the dental industry. By standardizing procedures, CAD/CAM technologies have been shown to be capable of creating high-quality manufactured components.5

Though these technologies offer increased speed, accuracy and consistency over conventional laboratory processing methods,6 dental CAD/CAM workflows can also be broken down into separate phases. This allows for greater customization and movement between digital and analog workflows for the user depending on their needs and level of expertise. In addition, the enhanced laboratory-clinician collaboration and data sharing that CAD/CAM software such as DTX Studio suite offers helps labs to stay up-to-date with changes easier than ever.

DTX Studio for NobelProcera CAD/CAM zirconia restorations

Zirconia and CAD/CAM

CAD/CAM’s integration into dental laboratory workflows has been driven in part by the increasing adoption of zirconia as a metal substitute.7 This relationship does not only go one way, however. Advances in dental CAD/CAM technology have been crucial for the development of high-strength ceramics.

The improved mechanical properties of current forms of zirconia, combined with their excellent natural esthetics, have helped to make this ceramic an increasingly popular option.8 Without CAD/CAM technologies, well-fitted prostheses using these materials would be extremely difficult to fabricate due to the material’s increased flexural strength and fracture toughness.9 CAD/CAM dental labs are able to design, mill and stain/glaze robust zirconia restorations in a controlled and predictable manner, leading to less stress for all involved. It is clear that CAD/CAM is integral to the continued success of zirconia as a restorative material.

CAD/CAM milling machineNobelProcera: Precision meets individualization

More than 30 years and 11 million units after its introduction, NobelProcera continues to be an industry leader in producing esthetic, precision-engineered dental restorations. With over 25 integrated scanners and multiple workflows, customers have flexibility to use their current scanner and software to design and order NobelProcera restorations with zero to little upfront cost. 10 NobelProcera’s high-translucency, monochromatic, multilayered full-contour zirconia solutions are indicated for a variety of screw- and cement-retained dental crowns and bridges, and are available in different base shades, allowing restorations between natural teeth to blend in harmoniously.

 

NobelProcera CAD/CAM zirconia restorations

Key benefits for dental labs

  • Full contour means that the restorations arrive in their final shape and with great occlusal detail. Since they only require finishing touches, time can be saved.
  • Full-contour zirconia restorations milled from a solid monobloc reduce the risk of chipping, in turn reducing stress and the need for remakes.
  • For restorations with high esthetic demands, the option for designing a cut-back and building the final shape by veneering is available.

Thanks to Nobel Biocare’s commitment to providing consistently high quality and intuitive CAD/CAM solutions, NobelProcera implant restorations have been proven to demonstrate a high level of precision fit,11 mechanical strength12 and long-term, reliable service,13 while still able to be individualized.

More to explore

References

  1. Gargari, M. et al. Strength of zirconia fixed partial dentures: review of the literature. Oral Implantol (Rome). 2010;3(4):15-24. 
  2. Bruno-Gohin, Céline et al. Biocompatibility study of lithium disilicate and zirconium oxide ceramics for esthetic dental abutments. J Periodontal Implant Sci. 2016;46(6):362-371.

  3. Zadeh, Parissa Nassary et al. Flexural strength, fracture toughness and translucency of cubic/tetragonal zirconia materials. J Prosthet Dent. 2018.
  4. Miyazaki, Takashi et al. A review of dental CAD/CAM: current status and future perspectives from 20 years of experience. Dent Mater J. 2009;28(1):44-56.
  5. Abduo J., Lyons K. Rationale for the Use of CAD/CAM Technology in Implant Prosthodontics. Int J Dent. 2013.

  6. . Samra, A.P.B. et al. CAD/CAM in dentistry – a critical review. Rev Odonto Cienc. 2016;31(3):140-144.
  7. Helvey, Gregg. Zirconia and computer-aided design/computer-aided manufacturing (CAD/CAM) dentistry. Functional Esthetics and Restorative Dentistry. 2007;1(3):28-39.
  8. El-Dessouky, R.A. et al. Marginal adaptation of CAD/CAM zirconia-based crown during fabrication steps. Tanta Dent J. 2015;12(2):81-88.

    Dauo, E.E. The zirconia ceramic: strengths and weaknesses. Open Dent J. 2014;8:33-42.

  9. Kim, R.W. et al. Ceramic dental biomaterials and CAD/CAM technology: state of the art. J Prosthet Research. 2014;58(4):208-216.
  10. Note: The FDA has not cleared all combinations of scanners and software for use with the NobelProcera system. 
  11. Katsoulis J, Mericske-Stern R, Rotkina L, Zbären C, Enkling N, Blatz MB. Precision of fit of implant-supported screw-retained 10-unit computer-aided-designed and computer-aided-manufactured frameworks made from zirconium dioxide and titanium: an in vitro study. Clin Oral Implants Res. 2014;25(2):165-174.

    Martínez-Rus F, Suárez MJ, Rivera B, Pradíes G. Evaluation of the absolute marginal discrepancy of zirconia-based ceramic copings. J Prosthet Dent. 2011;105(2):108-114.

  12. Truninger TC, Stawarczyk B, Leutert CR, et al. Bending moments of zirconia and titanium abutments with internal and external implant-abutment connections after aging and chewing simulation. Clin Oral Implants Res 2012;23(1):12-18.
  13. Zembic A, Bosch A, Jung RE, et al. Five-year results of a randomized controlled clinical trial comparing zirconia and titanium abutments supporting single-implant crowns in canine and posterior regions. Clin Oral Implants Res 2013;24(4):384-390.

    Ozer F, Mante FK, Chiche G, et al. A retrospective survey on long-term survival of posterior zirconia and porcelain-fused-to-metal crowns in private practice. Quintessence Int 2014;45(1):31-38.

Posted by Nobel Biocare