Introduction: The aim of prosthodontics is the production of fixed prosthodontic restoration which resemble and function like natural teeth. Dental ceramics are one of the best materials which can fulfill these goals. Purpose: The purpose of the thesis is to present Lithium Disilicate ceramic material, its properties and dental laboratory technologies and methods of use. Methods: The thesis consists of lithium-disilicate ceramics theoretical background, the literature overview and presentation of two laboratory production technologies – ceramic Heat Pressing and CAD/CAM technology. Results: Cast model and die preparation is equal for the both technologies. Described are in details all procedures for the Heat Pressing and for the CAD/CAM technology. Heat Pressing: the restoration wax up and investment ring was prepared with preheating and pressing of ingot into the investment ring mould form in the ceramic furnace, followed divesting of restoration and final staining and glazing. CAD/CAM technology: model scanning, CAD procedures, soft ceramic milling, final crystallization of restoration in ceramic furnace followed by porcelain layering or for the monolithic type of restoration staining and glazing are described. The survival rate of 97,7 % and 1,7 % of cracking in clinical studies show that lithium disilicate system is better then metal ceramics. The survival rate for crowns, inlays, onlays and esthetic veneers is ten times better then for short bridges made of this material. That is why the new zirconium oxide ceramics was introduced for bridges. Discussion and conclusion: Due to excellent esthetics, mechanical and functional properties and good clinical results the lithium disilicate enables a wide range of indication in fixed prosthodontics. IPS e.max Press Multi is an excellent new ingot enabling translucency and adequate opacity in monolithic restoration. It is expected bright future for lithium disilicate ceramics.
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