Today, the main reasons for applying restorative dental materials is not only to restore dental tissues lost because of caries or trauma, but also to correct the form and colour of teeth for social acceptance. In some parts of the world, it is estimated that up to 50 percent of individuals seek dental care simply to improve the appearance of their dentition.1 In reconstructive dentistry, missing dental tissues can be restored through a number of treatment options.
For many years, full-coverage crowns were considered the most predictable treatment option. In a systematic review, the estimated survival rates of such restorations were reported to be 95.6 percent for metal-ceramics, and between 87.5 and 96.4 percent for all-ceramic materials after 5 years of function.2 Recent practice-based evidence showed less favourable results of 63 percent for metal-ceramic and 48 percent for all-ceramic crowns for up 10 years.3 Unfortunately, full-coverage crowns require substantial removal of sound dental tissues to gain space for the restorative material, and to achieve macro-retention. This can weaken the tooth, which might lead to pulpal injuries, and patient discomfort during or after drilling. Biological complications were rare; however, there is a 2.1 percent loss of vitality and a 1.8 percent risk of caries.2
Owing to great progress in adhesive technologies, restorations in the form of laminate veneers, sectional veneers, inlays, onlays, and overlays can be bonded onto the enamel and dentin, with the existing restorations requiring minimal or no tooth preparation. This enables clinicians to preserve the enamel that protects the dentin and the pulp.4 Therefore, classical full-coverage restorations are presently considered to be invasive treatment modalities.
Particularly, restoration of the anterior dentition can be performed with laminate veneers. A laminate veneer is a thin layer of ceramic (indirect) or resin-based composite (direct or indirect) covering the buccal surface of the tooth. These require a minimal preparation depth of 0.3–0.8 mm of the tooth to obtain sufﬁcient thickness for the material to attain the necessary form and colour.5,6 This is approximately one-quarter to one-half the amount of tooth reduction needed for full-coverage crowns.5