Commissural lip pit UMLS:C0399605 HP:0002710 Pits at the corners of the lips Commissural lip pits have no relationship to other forms of lip pits which may be located on the vermilion of the upper or lower lip, usually paramedian. Rather, commissural pits are located at the corners of the oral aperture. Commissural pit Commissural labial pits A depression located at an oral commissure. Lip pits at corners of the mouth Lip pit