Objectives: Porcelain veneers are steadily increasing in popularity among today's dental practitioners for conservative restoration of unaesthetic anterior teeth. As with any new procedure, in vitro and in vivo investigations are required to assess the ultimate clinical efficacy of these restorations. The current literature was therefore reviewed in search for the most important parameters determining the long-term success of porcelain veneers.
Data sources: Laboratory studies focusing on parameters in prediction of the clinical efficacy of porcelain veneers such as the tooth preparation for porcelain veneers, the selection and type of the adhesive system, the quality of marginal adaptation, the resistance against microleakage, the periodontal response, and the aesthetic characteristics of the restorations have been reviewed. The clinical relevance of these parameters was then determined by reviewing the results of short and medium to long-term in vivo studies involving porcelain veneers performed during the last 10 years.
Conclusions: The adhesive porcelain veneer complex has been proven to be a very strong complex in vitro and in vivo. An optimal bonded restoration was achieved especially if the preparation was located completely in enamel, if correct adhesive treatment procedures were carried out and if a suitable luting composite was selected. The maintenance of aesthetics of porcelain veneers in the medium to long term was excellent, patient satisfaction was high and porcelain veneers had no adverse effects on gingival health inpatients with an optimal oral hygiene. Major shortcomings of the porcelain veneer system were described as a relatively large marginal discrepancy, and an insufficient wear resistance of the luting composite. Although these shortcomings had no direct impact on the clinical success of porcelain veneers in the medium term, their influence on the overall clinical performance in the long term is still unknown and therefore needs further study.