Porcelain and resin veneers clinically evaluated: 2-year results. A clinical comparison of two different types of dental veneers--baked porcelain veneer and heat-and-pressure processed urethane resin veneer--was made after 2 years. Although the esthetic appearance and gingival response were equal for both systems, the resin veneers had a greater tendency to chip and fracture. By the end of 2 years, 20% of the resin veneers had failed, whereas all of the porcelain veneers remained. 