The use of silicones for the purpose of increasing the volume of soft tissues has not only become a controversial topic for health but also the idea that it is possible to achieve the ideal body. At the end of the 1950s and the beginning of the 1960s, thanks to cinema and advertising, the first sex symbols appeared that somehow created a profile of beauty in the collective imagination. This cultural construction of the perfect body is partly responsible for the proliferation of the use of surgical and non-surgical aesthetic treatments, some with more adverse effects than others. Although the complications involved in these procedures began to be described in the medical literature, the literature on siliconomas continues to be scarce, nor is the incidence and prevalence of siliconomas in the female population reliably known. First of all, it is necessary to differentiate the encapsulated breast prosthesis from the injection of liquid silicone or other substances; the use of the latter is prohibited by all medical societies. However, both procedures can have serious adverse effects, with more severe injections of liquid silicone, paraffin, industrial oil, among others. This chapter addresses the clinical presentation and diagnosis of these complications. Whatever the mechanism by which silicone enters the body, it is estimated that it migrates through the lymphatic and hematogenous routes, triggering a foreign body reaction that causes granulomas or siliconomas. The greatest difficulty is establishing the differential diagnosis between breast siliconomas and breast cancer. Patients with hardened breasts, nodules, or indurated masses may mimic advanced breast cancer. Early detection is essential so as not to delay therapy. The severity of systemic manifestations ranging from pulmonary, neurological, cardiac, hepatic or gastrointestinal involvement, silicone embolization syndrome, adjuvant-induced autoimmune syndrome (ASIA), and other systemic immunological alterations (scleroderma, lupus) to sepsis should also be considered.