Upper jaw in human cyclopia.

In human cyclopia the upper jaw forms a solid bony mass between the median orbit and the oral cavity. The skeletal elements forming the upper jaw have been studied in serial sections through the median third of the head in 3 perinatal human specimens presenting with a median orbit and proboscis. One head was sectioned in the sagittal plane and 2 in the coronal plane. The upper jaw has also been studied in a dried cyclops skull and in a desiccated cyclops head in which the roof of the orbit had been removed. The data obtained demonstrate the particular contributions made by the lacrimal bones, the maxillae and the palatine bones to the upper jaw in human cyclopia. The effects of the absence of the frontonasal process contribution and of the absence of the nasal cavity on the upper jaw in cyclopia are considered.