Trophic ulceration of the nose is a rare complication occurring in patients with trigeminal anaesthesia. The etiology is not clear, but self-inflicted injuries to an anaesthetic region are considered to play an important part. The authors' experience with three cases indicates that substitution with skin from the affected area of the face will not give a lasting result. It seems probable that only skin with an intact nerve supply can provide a permanent replacement for skin lost in the dystrophic process. This means that a local flap innervated from a non-affected part of the face would offer the best possibility of a permanent cover for these defects.