https://github.com/cmungall, https://github.com/tmeehan

http://purl.obolibrary.org/obo/The_Periodontium.jpg

The fibrous connective tissue that surrounds the root of a tooth, separating it from and attaching it to the alveolar bone. It extends from the base of the gingival mucosa to the fundus of the bony socket, and its main function is to hold the tooth in its socket[BTO]. It consist of cells, extracellular compartment of fibers. The cells are fibroblast, epithelial, undifferentiated mesenchymal cells, bone and cementum cells. The extracellular compartment consists of collagen fibers bundles embedded in ground substance. The PDL substance has been estimated to be 70% water and is thought to have a significant effect on the tooth's ability to withstand stress loads[WP][BTO:0001020, Wikipedia:Periodontal_fiber, https://github.com/obophenotype/uberon/issues/21]., The collagen fibers, running from the cementum to the alveolar bone, that suspend a tooth in its socket; they include apical, oblique, horizontal, and alveolar crest fibers, indicating that the orientation of the fibers varies at different levels[http://www.drugs.com/dict/desmodentium.html].

FMA treats periodontium and periodontal ligament as the same; it has a separate class desmodentium, which we place here even though it is classified as fetal in FMA

uberon

paradentium, peridental membrane, peridontal ligament, peridontal fibre, peridontal ligament fiber, peridontal fiber, peridontal ligament fibre, peridontal membrane, periodontium, odontoperiosteum, alveolodental ligament, alveolodental membrane, alveolar periosteum, PDL, desmodontium, peridontium

UBERON:0008266

http://purl.obolibrary.org/obo/FMA_76870

• gingiva