Lesch-Nyhan syndrome and the lower lip guard.

Lesch-Nyhan syndrome, a rare inborn error of metabolism, is characterized by mental retardation and factitious oral lesions, which cause immense difficulties in its management. A case of an 11-year-old boy, the elder of two siblings with this condition, who had severe self-inflicted injuries to oral and perioral tissues is presented highlighting the different treatment modalities considered. A tailor-made lipguard proved to provide the best cosmetic result short term.