As the role of porcelain veneers expands, dentists increasingly find themselves balancing esthetic advantage against material limitations. In a majority of clinical situations that use veneers, backed feldspathic porcelain has been used with great success and should be considered the material of choice. However, it has been reported that feldspathic porcelain veneers are brittle, prome to time-dependent stress failure and have a low flexural strength (60 to 70 ㎫). The sintering of the porcelain particles creates micropotosities and irregularities between ceramic particles, which gives porcelain low tensile strength and susceptibility to cracks. Therefore, the use of porcelain veneer in case of tooth fracture or large diastema closure is questionable. So the use of pressed ceramic systems for 'difficult' veneer cases, such as required bulk or function under load is recommended.
Recently, IPS Empress ®2 glass-ceramic (Ivoclar North America, Amherst, NY) has been used as an all ceramic material fot 3 unit ceramic bridges, crowns, inlays, onlays and veneers. The final restoration, mode of lithium disilicate framework ceramic and fluoroapitite layering ceramic, offers clinical benefits in terms of high flexural strength (350~450 ㎫), low were of opposing tooth structure, esthetics similar to natural tooth and marginal adaptation. The purpose of this case is to report successful laminate veneer restorations using IPS Empress ®2 system in case of diastema, discoloration and fracture of upper anterior teeth and peg lateralis.
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