CAD/CAM - international magazine of digital dentistry

I industry report _ aesthetic dentures _Introduction When damage to dentition is too severe for restorative treatment to be feasible, conven- tional dentures have been the treatment of choice. Conventional dentures, however, can be foul smelling and uncomfortable.1 Additionally, jawbone resorption causes the dentures to be- come loose over time requiring readjustment of the jaw to ensure a proper fit.2 In some cases, if resorption has already oc- curred, the patient will no longer have sufficient bone structure to support dentures.2 To over- come the disadvantages associated with con- ventional dentures, new implant materials and techniques have been developed, providing the growing edentulous population with more op- portunities for functional, stable and comfort- able treatments as well as decreased bone loss.3 Due to the amount of masticatory forces placed on the prostheses as a result of implant sup- port, stronger, more durable substructures and denture teeth are necessary to accommodate wear.3 Zirconia is one of the strongest materials available in the dental industry today demon- strating a flexural strength of approximately 900–1,100MPa.4 Idealforhigh-stressrestorations, including implant dentures, zirconia restora- tions boast a failure-free reputation according to current research.5 Designed and fabricated using CAD/CAM technology, zirconia substruc- tures are stronger and more durable than tra- ditional denture prostheses.6 Innovative tech- niques provide long-term and patient-pleasing results. When fitted with customised lithium disili- cate dentition, fixed implant prosthetics will not develop a foul smell, require no realignment and provide a predictable, highly aesthetic and life- long solution. In addition, CAD/CAM technology can be used in the office or laboratory for indi- cations including full-mouth restorations, fixed partialdentures,implantabutments,crowns,ve- neers, inlays, and onlays,7 contributing to faster and easier restorative treatments. Suitable for restorations requiring high strength and exceptional durability, IPS e.max ZirCAD (IvoclarVivadent)isayttrium-stabilisedzirconia demonstrating a flexural strength of more than 900 MPa, and a fracture toughness of more than twice that of glass-ceramic materials.8 With approximately 50 per cent porosity, the pre-sintered blocks allow easy processing. Yet, once sintered to full density, its superior strength and inertness make it an ideal materi- al for dental restorations.8 IPS e.max ZirCAD blocks (Ivoclar Vivadent) meet the functional re- quirements demanded by posterior masticatory forces. Despite the use of different IPS e.max frame- work materials (lithium disilicate or zirconium oxide), aesthetic results can still be achieved due toaselectionofnaturalandshadedpre-sintered zirconium oxide blocks for colour versatility, and when layered with aesthetic ceramic materials, The finesse of the pink and the power of IPS e.max Authors_Rafael Santrich & Dr Larry Grillo, USA 26 I CAD/CAM 4_2013