Foreign body aspiration (FBA) is a serious medical problem, also in dental practice. The case report describes the case of a patient who for 12 years has suffered from chronic cough as a result of the aspiration of a polymeric silicone resin fragment during a dental procedure. In November 2002, the patient was underwent dental care, and she points out that, when performing dental imprint, she had sensed that something "went down in the throat" but she was immediately reassured by the dentist. After lung CT was performed, the foreign body was identified and removed with benefit to the patient. The knowledge of this case report could be useful for dentists who perform dental impressions, to be aware of the fact that the material used is radiolucent e.g. cannot be seen on plan radiographs and it can be accidentally inhaled by the patient. The knowledge of the case is also important for doctors who come in contact with patients who previously underwent dental treatment, suffering from persistent cough, in the absence of positive radiological signs.