As it is known, fixed crown bridge prostheses, in other words veneers, come at the beginning of the applications performed for functional reasons or aesthetic purposes, such as tooth loss or excessive loss of substance in the tooth. They are produced from materials such as ceramic, metal-ceramic, zirconium-ceramic. When such a treatment is required, it is necessary to provide maximum aesthetics. The color, shape, dimensions and fit of the prosthesis, as well as its compatibility with the gingiva, are also effective in providing aesthetics and long-term use of the prosthesis.
No matter what material is used, in the preparation of the prosthesis, both the metal thickness (0.3-0.5 mm) and the thickness of the ceramic (1mm) are involved in the preparation of the stepped tooth cut very porcelain (veneers and bridges). becomes much more important. If the metal + ceramic thickness is considered as 1.5 mm in total and if the tooth surface at the gingival edge is not abraded by 1.5 mm to form a step while cutting the tooth, the edges of the prosthesis made will protrude beyond the limits of the tooth. In this case, an area is formed where food residues accumulate and cannot be easily cleaned by tooth brushing. This causes gingival irritation, redness and edema. This situation is not perceived when the prosthesis is first attached, but over time it starts with bleeding during brushing and then continues as slight swelling and redness. While this situation is a factor that will seriously disrupt the aesthetics even in this state, the event grows gradually, the edges of the prosthesis hold more food residues and eventually there is gingival recession in that area. This means both a very bad appearance and a gradual deterioration of dental health.
In fixed crown bridge prostheses made for aesthetic reasons or loss of function, the compatibility of the prosthesis with the gingiva is very important. And to ensure this harmony, during tooth cutting, the edges of the prosthesis, from the tooth borders, to the gingiva. It depends on the step thread cutting to ensure that it does not overflow correctly.