The present invention provides a tissue expander (10) comprising a self-inflating core (12) having a non-inflated state and an inflated state and a coating (14) surrounding said core (12), wherein said core (12) comprises two or more segments (16) of dried compacted material of height H joined to each other by conformable linking portions (18) of height h where H is greater than h. the conformable linking portions (18) allow for the expander (10) to be conformed to a desired profile either before or after insertion under the skin of a patient.
