Introduction: Imaging differential diagnosis of polymethylmethacrylate (PMMA) and liquid silicone is important for both reaching a diagnosis itself and differentiating lesions; thus, allowing a correct evaluation of the material used as ller. Objective: The analysis of cases in which PMMA and silicone were used as llers and the differentiation of both llings by magnetic resonance imaging. Methodology: A retrospective study of the records of 12 patients who had undergone lling with either PMMA or silicone. Magnetic Resonance Imaging (MRI) was used as a form of diagnosis and/or treatment follow-up. Conclusion: MRI is considered the gold standard test for clinical diagnosis since liquid llers are difcult to be identied in the physical exam. Its use allows the possible differentiation between procedures performed with PMMAand silicone.