Hereditary sensory and autonomic neuropathy (HSAN) is a rare syndrome which is seen in early childhood. Five different types are described. Absence of pain and self-mutilation are characteristic findings of this syndrome. Teeth in the oral cavity can cause damage to the oral tissues and tongue. When it is diagnosed, there should be co-operation between dentist and neurologist. Using an oral shield prevents the biting and, thus, traumatization of the tissues can be prevented. A case report which is diagnosed as HSAN type 4 is presented and information submitted about its treatment.