Objective: Since the early 1980s, topical silicone sheets have been used in the treatment of hypertrophic scars and keloids.This study aimed to determine the optimal duration and application of these sheets. Design: multi-centered therapeutic study. Setting and participants: A total of 224 patients were included in this study; 205 patients with hypertrophic scars and 19 patients with keloids. Patients received treatment with a topical silicone sheet. Treated scars varied in age, ranging from two weeks to 62 years and treatment time ranged from one month to 16 months. Assessment of the scars was performed by the use of standardized study forms and digital photography. Measurements: Skin therapists objectively assessed the scars on its color, thickness, and elasticity. Patients themselves subjectively assessed their perception of their scar and their experience with the usage of the topical silicone sheet. Results: After applying the topical silicone sheet, all scars, regardless of type of scar and maturity, improved significantly in color, thickness, and elasticity. Conclusion: In this study, treatment with the topical silicone sheet showed significant improvement on both hypertrophic scars and keloids. Best results were reached when the silicone sheet was applied at least four hours per day.