Wear of prosthodontic resin facings in 176 metal-resin canine crowns and retainers for fixed partial dentures was studied in clinical photographs and assessed using a graded scale. Four cross-sectional groups of restorations were studied according to length of clinical service (1, 3, 6, and 9 years). The criteria used during the examination described loss of substance in relationship to the metal cast framework. The method was tested for reliability and consistency. The results showed that the extent of wear increased with increasing time of clinical service (P less than .05). More severe wear scores were assigned to restorations in female patients than to those in male patients (P less than .05), to the mandibular facings compared to those in the maxillae (P less than .05), and the incisal areas of the facings compared to the cervical areas (P less than .05). Patients instructed