Retromolar space
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.
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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.
References
- Bastir, Markus; O'Higgins, Paul; Rosas, Antonio (May 7, 2007). "Facial ontogeny in Neanderthals and modern humans". Proceedings of the Royal Society B: Biological Sciences. 274 (1614): 1125–1132. doi:10.1098/rspb.2006.0448. PMC 2189570. PMID 17311777.
- 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.
- Sharma, Anil; Deep, Anchal; Siwach, Amit; Singh, Manas; Bhargava, Akshay; Siwach, Reenu (May 2016). "Assessment and Evaluation of Anatomic Variations of Retromolar Pad: A Cross Sectional Study". Journal of Clinical and Diagnostic Research. 10 (5): ZC143–ZC145. doi:10.7860/JCDR/2016/19551.7880. PMC 4948526. PMID 27437350.