| dr | dorsal root; drain; dram; dressing |
|---|---|
| DRC | damage risk criterion; dendritic reticulum cell; diagnostic reporting console; digitorenocerebral [s... |
| DRD | dihydroxyphenylalanine-responsive dystonia; dorsal root dilator |
| DREZ | dorsal root entry zone |
| DRG | diagnosis-related group; Division of Research Grants [NIH}; dorsal respiratory group; dorsal root ga... |
| medial root of optic tract | The smaller division of the posterior end of the optic tract that disappears under the medial geniculate body. Synonym: radix medialis tractus optici. (05 Mar 2000) |
|---|---|
| root | <botany> The water- and mineral-absorbing part of a plant which is usually underground, does not bear leaves, tends to grow downwards and is typically derived from the radicle of the embryo. See: adventitious. (09 Oct 1997) |
| root abscess | A pocket of pus adjacent to or within (apical abscess) the tooth's root caused by plaque and calculus invasion. Symptoms include tooth pain and tenderness that may be accompanied by facial swelling and a fever. Treatment includes antibiotics and a thorough cleansing of the infected site by a dentist. See: apical abscess. (27 Sep 1997) |
| root amputation | Surgical removal of one or more roots of a multirooted tooth, the remaining root canal(s) usually being treated endodontically. Synonym: radectomy, radiectomy, radisectomy. (05 Mar 2000) |
| root apex | The tip of a tooth root, the part farthest from the incisal or occlusal side. Synonym: apex radicis dentis, root apex, root tip. (05 Mar 2000) |
| root avulsion | The tearing away of the anterior and posterior primary nerve roots from the spinal cord, due to severe traction; most often the C5 through T1 roots are affected. (05 Mar 2000) |
| root cap | <botany> A mass of parenchymtous cells which covers and protects the growing cells at the end of a root; a pileorhiza. The issue found at the apex of roots, overlying the root apical meristem and protecting it from friction as the root grows through the soil. Secretes a glycoprotein mucilage as a lubricant. (18 Nov 1997) |
| root caries | Dental caries involving the tooth root, cementum, or cervical area of the tooth. (12 Dec 1998) |
| root caries index | The ratio of the number of teeth with carious lesions of the root, and/or restorations of the root, to the number of teeth with exposed root surfaces. (05 Mar 2000) |
| root cutting | <botany> Part of a root of a woody plant which, under suitable conditions, takes root and forms a new plant. (09 Oct 1997) |
| root dehiscence | A loss of the buccal or lingual bone overlaying the root portion of a tooth, leaving that area covered by soft tissue only. (05 Mar 2000) |
| root end cyst | An inflammatory odontogenic cyst derived histogenetically from Malassez' epithelial rests surrounding the root apex of a nonvital tooth. Synonym: periapical cyst, radicular cyst, root end cyst. (05 Mar 2000) |
| root end granuloma | Chronic nonsuppurative inflammation of periapical tissue resulting from irritation following pulp disease or endodontic treatment. (12 Dec 1998) |
| root filaments | The small, individual fibre fascicles into which the roots of all of the spinal nerves and several cranial nerves (hypoglossus, vagus, oculomotorius) divide in fanlike fashion before entering or leaving the spinal cord or brainstem; the spinal dorsal root may divide into 8 to 12 such rootlets. Synonym: fila radicularia, root filaments. (05 Mar 2000) |
| root foramen | The opening at the apex of the root of a tooth that gives passage to the nerve and blood vessels. Synonym: foramen apicis dentis, apical dental foramen, root foramen. (05 Mar 2000) |