Electrical burns of the mouth in toddlers often result from sucking on the free end of a "live" multiple-outlet extension plug. Recognition of the characteristic oral sign is requisite for proper management.
Ackerman AB, Goldfaden GL. Electrical Burns of the Mouth in Children. Arch Dermatol. 1971;104(3):308-311. doi:10.1001/archderm.1971.04000210082016