BACKGROUND The present study aimed to compare the clinical performance and gingival sulcus width changes in partially edentulous patients using cotton and polymer gingival retraction cords. MATERIAL AND METHODS Fifty partially edentulous patients were divided into 2 groups (Gp C and Gp P) and were subjected to single crown/fixed partial denture treatment. Clinical parameters, including plaque index scores, placement time, and hemorrhage control scores, were assessed. Gingival sulcus width changes before and after retraction were evaluated using individual type 4 dental stone dies observed under an optical microscope. Statistical analysis was performed using dependent/independent t tests. RESULTS The mean placement time, hemorrhage control time, and hemorrhagic scores were lower in Gp P than in Gp C, indicating better clinical performance of polymer-based retraction cord. Both groups showed an increase in sulcus width after retraction, but Gp P had a significantly higher sulcus width (690.03±45.37) compared to Gp C (471.38±28.13). The mean difference in sulcus width between baseline and after retraction was also significantly higher in Gp P (525.84 micrometers) than in Gp C (309.11 micrometers). CONCLUSIONS The present study shows that polymer-based cords produce more sulcus width and have better clinical performance compared to cotton-based gingival retraction cords. These results suggest that the use of polymer-based retraction cords can improve the quality of dental impressions in partially edentulous patients.