Crown prostheses are prostheses used to restore teeth in cases where material has been lost due to various reasons and there are different aesthetic expectations (coloration, active interfacial caries, gaps between teeth).
Bridge prostheses, on the other hand, are prostheses made by supporting the teeth adjacent to the gap in cases where edentulous cavities are present and the teeth adjacent to the edentulous gap are healthy. With bridge prostheses, aesthetic and phonetic needs are provided and at the same time, the continuity of chewing function can be provided.
With crown and bridge prostheses supported by metal infrastructure, weak porcelain can be supported. However, the presence of gray discoloration in the gingival area and the opaque appearance of porcelain in prostheses supported by metal infrastructure create aesthetic problems, as well as problems such as hygiene problems and allergies. Due to these problems, as a result of the researches in the field of dentistry, the structure of porcelain was strengthened and tooth-colored infrastructure porcelains were developed.
Metal-free (full-ceramic) crown and bridge prostheses can be applied in cases such as loss of material due to various reasons (cavities, fractures), removal of discoloration of teeth, closure of gaps between teeth (diastema), correction of crowding.
The increase in aesthetic expectations has led to an increase in the search for infrastructure in tooth color. While the developed systems could only be used for single crown restoration in the anterior region at first, porcelains that could be used in 3-member bridge prostheses were developed later on. With the use of zirconium in dentistry and the increase in the use of computer aided (CAD/CAM) systems, the use of zirconium-based full ceramic crown and bridge prostheses has become widespread. Full ceramic crown and bridge prostheses with zirconium infrastructure can be used in all cases where metal-supported porcelain prostheses can be applied. In this way, the optical properties of natural teeth can be successfully imitated. Incoming light reaches the gingiva by refracting through different ceramic layers, and a pink and lively appearance can be obtained in the gingiva, as in natural teeth. In addition to its superior optical properties, zirconium material has a long clinical life due to its tissue-friendliness and non-allergic-toxic properties.
