Significant progress in dental adhesion over the past few decades has influenced the selection of restorative materials in dental practice. Objective: To examine the dental materials used to restore primary caries in permanent tooth surfaces by Dental Practice-Based Research Network (DPBRN; www.DPBRN.org) clinicians. DPBRN comprises practices from five regions: AL/MS: Alabama/Mississippi; FL/GA: Florida/Georgia; MN: dentists employed by HealthPartners and in private practice from the Minneapolis, Minnesota area; PDA: Permanente Dental Associates in cooperation with Kaiser Permanente Center for Health Research; and SK: Denmark, Norway, and Sweden. Methods: A total of 195 practitioner-investigators collected data on 7558 restorations due to caries in un-restored permanent tooth surfaces from 5078 patients. Information included the restorative material including base, liner or resin-based bonding material employed by restoration class. Results: Direct composite resin (47%) was frequently used, followed by amalgam (37%); glass-ionomer or resin-modified glass ionomer (2%); temporary material (1%); combined metal-ceramic (0.4%); cast gold or other metallic-base (0.08%); ceramic or porcelain (0.07%); and indirect composite restorations (0.06%). These materials were used on 2840 (37%) Class II; 2014 (27%) Class I; 1712 (23%) Class V; 903 (12%) Class III; and 89 (1%) Class IV restorations. Composite resin was frequently used in all restorations, except for Class II preparations, where amalgam was the primary material (63 % amalgam vs. 32% composite). Composite was mostly placed with a resin-based bonding material, whereas amalgam was placed without any base material (36%) or with the use of varnish (12%), resin-modified glass-ionomer liner (11%), resin-based bonding material (8%), or calcium hydroxide-based liner (6%). Conclusion: Composite resin is largely used to restore anterior and occlusal surfaces of posterior teeth affected by caries. Despite the greatly enhanced properties of adhesive materials, amalgam remains a common choice to restore posterior teeth with proximal caries by DPBRN practitioner-investigators. Support: NIDCR-NIH U01-DE 16746 and 16747.