The retromolar space or retromolar gap is a space at the rear of the mandible, between the back of the last molar and the anterior edge of the ascending ramus where it crosses the alveolar margin.
This gap is generally small or absent in modern humans, but it was more often present in Neanderthals,[1] and it was common among some prehistoric Amerindians, such as Arikara and Mandan.[2][3]
Retromolar pad
The retromolar area of a human mandible is covered by the retromolar pad (also known as the piriformis papilla), an elevated triangular area of mucosa. It is composed of non-keratinized loose alveolar tissue covering glandular tissues and muscle fibers.[4] It is important for supporting lower complete and partial dentures as well as landmarking in the fabrication of dentures.
^De la Cova, C. (July–August 2016). "The Retromolar Space: A Morphological Curiosity Observed Amongst the Protohistoric Arikara and Mandan". International Journal of Osteoarchaeology. 26 (4): 610–620. doi:10.1002/oa.2451.
^Suzuki, H. (1970). "Skull of the Amud Man". In Suzuki, H.; Takai, F. (eds.). The Amud Man and his Cave Site. Tokyo: Academic Press of Japan. p. 166. The linea obliqua of the mandibular ramus [of Amud 1] goes down far behind M3, and runs into the low prominentia lateralis below the distal part of M3. For this reason, when the Amud mandible is viewed from the side, a free portion or a gap 14 mm wide is recognizable between M3 and the linea obliqua. In modern man, this gap does not usually exist.
