Current status on lithium disilicate and zirconia: a narrative review

Abstract

Background: The introduction of the new generation of particle-filled and high strength ceramics, hybrid composites and technopolymers in the last decade has offered an extensive palette of dental materials broadening the clinical indications in fixed prosthodontics, in the light of minimally invasive dentistry dictates. Moreover, last years have seen a dramatic increase in the patients' demand for non-metallic materials, sometimes induced by metal-phobia or alleged allergies. Therefore, the attention of scientific research has been progressively focusing on such materials, particularly on lithium disilicate and zirconia, in order to shed light on properties, indications and limitations of the new protagonists of the prosthetic scene. Methods: This article is aimed at providing a narrative review regarding the state-of-the-art in the field of these popular ceramic materials, as to their physical-chemical, mechanical and optical properties, as well as to the proper dental applications, by means of scientific literature analysis and with reference to the authors' clinical experience. Results: A huge amount of data, sometimes conflicting, is available today. Both in vitro and in vivo studies pointed out the outstanding peculiarities of lithium disilicate and zirconia: unparalleled optical and esthetic properties, together with high biocompatibility, high mechanical resistance, reduced thickness and favorable wear behavior have been increasingly orientating the clinicians' choice toward such ceramics. Conclusions: The noticeable properties and versatility make lithium disilicate and zirconia materials of choice for modern prosthetic dentistry, requiring high esthetic and mechanical performances combined with a minimal invasive approach, so that the utilization of such metal-free ceramics has become more and more widespread over time.

Three‐year clinical performance of monolithic and partially veneered zirconia ceramic fixed partial dentures

“…In recent years, the use of zirconia in dentistry has expanded rapidly due to increasing demand for metal‐free restorations . The material meets the mechanical and functional requirements of dental prostheses to such an extent that it is particularly suitable for long‐term restorations .…”

Ceramic Materials and Technologies Applied to Digital Works in Implant-Supported Restorative Dentistry

“…Lithium disilicate (LS2) glass ceramic is one of the most popular all-ceramic systems currently used in the fabrication of single and multi-unit dental restorations due to its excellent mechanical and optical properties. Initially, this material was made commercially available as ingots, introduced to the market in 1998 with the name "IPS Empress 2" (Ivoclar Vivadent, Schaan, Liechtenstein), to be utilized according to the "heat-pressing" fabrication procedure, which is similar to the classic "lost wax" technique [100,101]. In 2005, a new formulation of LS2 was marketed as "IPS e.max Press" (Ivoclar Vivadent, Schaan, Liechtenstein), exhibiting improved mechanical properties and optical features which were much better than those of the older glass ceramics [101].…”

“…Initially, this material was made commercially available as ingots, introduced to the market in 1998 with the name "IPS Empress 2" (Ivoclar Vivadent, Schaan, Liechtenstein), to be utilized according to the "heat-pressing" fabrication procedure, which is similar to the classic "lost wax" technique [100,101]. In 2005, a new formulation of LS2 was marketed as "IPS e.max Press" (Ivoclar Vivadent, Schaan, Liechtenstein), exhibiting improved mechanical properties and optical features which were much better than those of the older glass ceramics [101]. Recently, the chairside CAD/CAM systems have been recognized as reliable systems allowing the introduction of ceramic blocks aimed at the production of restorations by SM, and are also suitable for the chairside production of restorations [4,[102][103][104].…”

Chairside gefertigte monolithische Zirkonoxidkronen – praktische Empfehlungen zu Materialauswahl und klinischem Vorgehen

“…In klinischen Studien zeigte sich jedoch, dass technische Komplikationen bei festsitzenden Restaurationen aus Zirkonoxidkeramik zumeist auf Frakturen der Verblendkeramik zurückzuführen sind (▶ Abb. 1) [3,7]. Zur Reduktion des Risikos technischer Komplikationen wurde bereits vor 10 Jahren mit der Entwicklung transluzenter Zirkonoxidkeramiken begonnen, die auch für die Herstellung monolithischer Restaurationen geeignet sind [8].…”