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The species was first described scientifically by American mycologist Howard James Banker in 1913. [2] Italian Pier Andrea Saccardo placed the species in the genus Hydnum in 1925, [3] while Walter Henry Snell and Esther Amelia Dick placed it in Calodon in 1956; [4] Hydnum peckii (Banker) Sacc. and Calodon peckii Snell & E.A. Dick are synonyms of Hydnellum peckii.
Brownish lines, the striae of Retzius, develop as a result of a change in the growth process. Macroscopically, these lines can be seen on the labial surface or lip side of anterior or front teeth as horizontal lines on the tooth crown, also known as perikymata or "imbrication lines" . [1]
Among adults with fully developed dentition, numerous techniques have been developed for age estimation by looking at various characteristics including periodontosis, cementum apposition, tooth-root translucency, [3] root resorption, secondary dentine deposition and the attrition of the occlusal surface. [10] The tooth-root translucency method ...
Roots are shallow and wide spreading; lateral root growth in a forest may be as far as 60 feet (18 m). [4] Generally, four to five lateral roots originate from the tree, and then branch within 2 feet (60 cm); vertical, penetrating roots near the base anchor the tree.
Some commonly held theories that have been disproven over time include: (1) the tooth is pushed upward into the mouth by the growth of the tooth's root, (2) the tooth is pushed upward by the growth of the bone around the tooth, (3) the tooth is pushed upward by vascular pressure, and (4) the tooth is pushed upward by the cushioned hammock. [40]
Cementum is a specialized bone like substance covering the root of a tooth. [15] It is approximately 45% inorganic material (mainly hydroxyapatite), 33% organic material (mainly collagen) and 22% water. Cementum is excreted by cementoblasts within the root of the tooth and is thickest at the root apex. Its coloration is yellowish and it is ...
The dental lamina is a band of epithelial tissue seen in histologic sections of a developing tooth. [1] [2] The dental lamina is first evidence of tooth development and begins (in humans) at the sixth week in utero or three weeks after the rupture of the buccopharyngeal membrane. It is formed when cells of the oral ectoderm proliferate faster ...
Growth from any such meristem at the tip of a root or shoot is termed primary growth and results in the lengthening of that root or shoot. Secondary growth results in widening of a root or shoot from divisions of cells in a cambium. [8] In addition to growth by cell division, a plant may grow through cell elongation. This occurs when individual ...