The aim of the present retrospective study was to observe the clinical and radiographic performances of a compomer (Dyract) in proximal restorations of primary molars as compared to amalgam restorations. The study was performed at the principal investigator's office. Children between three to eleven years old, who had at least two primary molars with a small to moderate approximal caries lesion were included in the study. The assessed material consisted of 107 proximal restorations (63 Dyract and 44 amalgam) placed in primary molars during the years 1994 to 1997 in forty-two children who were available for follow-up examinations. All the evaluated restorations were clinically acceptable, with smooth surface appearance, satisfactory color match, neither secondary caries nor fracture. The margins of two Dyract restorations presented minimal stain. Of the 63 Dyract restorations evaluated radiographically, two presented with bubbles, one with an overhang, and nine had pooling at the tooth-restoration interface. Minimal overhangs were disclosed in six amalgam restorations, and neither bubbles nor defects were seen at the tooth-restoration interface. These differences were statistically significant (p < 0.001). Based on the clinical performance of the material and on the radiographic findings, the authors conclude that Dyract can be a suitable alternative for restoring primary teeth that need to be retained up to two years. More extensive follow-up is needed to assess longer-term performance.