US Patent 11547155 External vacuum expander with non-adhesive rim

A tissue expander having a shell, an opening in the shell in communication with an external vacuum source to apply a vacuum within the shell and impart a distracting force to expand tissue, and a rim connected to the shell and adapted to be in contact with a skin of a patient. The rim is non-fixedly attached to the skin of the patient and moves laterally outwardly with respect to the shell under application of the vacuum.