INCLUSION CRITERIA:  Patients in need of single tooth restorations on posterior teeth. Age range: between 18 years of age. No contraindications for dental treatment. Good oral hygiene. No periodontal disease or treated periodontal disease. Absence of temporomandibular disorder and/or untreated habits or parafunctions.  Inclusion criteria for abutment teeth:  Posterior tooth requiring placement of a single tooth restoration. Restorability: with a crown:root ratio of at least 1:1. The presence of an unrestored or minimally restored natural antagonist tooth (teeth with no more than a Class II restoration), in the same quadrant as the treated tooth (G1,2,3). The presence of two unrestored or minimally restored antagonist teeth (in the same quadrants or on the contralateral side) (G4 or control). Minimum height of the dental stump: 3mm.  EXCLUSION CRITERIA:  Exclusion criteria for abutment teeth:  Antagonist tooth with a full coverage restoration. Opposing arch with fixed or removable partial denture. Lack of occlusal contact points in the enamel of the control teeth.