A compend of dental pathology and dental medicine : containing the most noteworthy points upon the subjects of interest to the dental student and a section on emergencies / by Geo. W. Warren.

  • Warren, George W. (George Washington), 1863-1934.
Date:
1903
Catalogue details

Licence: Public Domain Mark

Credit: A compend of dental pathology and dental medicine : containing the most noteworthy points upon the subjects of interest to the dental student and a section on emergencies / by Geo. W. Warren. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    twelve to fifteen yeai's coiuing- to such maturity as to emerge from the giim. Calcification. The Calcification of the Enamel.—The deposition of lime salts., which gives the teeth their characteristic hardness and is termed calcification, commences at the surface of the dentine and proceeds outward, each enamel rod taking the form of the cell, which in their compactness take on various shapes, usually, however, hexagonal, and the lime salts from each are depos- ited in close contact with each contiguous cell; there being but a very small amount of animal matter, the cement material be- tween them. When it is completed the enamel organ disappears and nourishment to the enamel can only be had through the surface lying nearest to the dentine, which is accomplished through osmotic action. The calcification of the dentine commences on the surface next to the enamel organ, and progresses from without inward, this being the point where mineralization begins in the tooth structure. The working cells of the dentine, the odontoblasts. throw out processes around which the lime salts are deposited, the processes leng-thening with the thickening of the cap of dentine; thus forming the tubular structure of dentine. The processes occupying the tubules of the dentine are simply pro- toplasmic prolongations. As age advances, both the tubuli and fibrilli decrease in size, and in old age the extremities are nearly or wholly obliterated. The Cementum.—The cells active in the formation of the Cementum are termed Cementohlasts. This structure is formed from the pericemental membrane, remaining as the residue of the dental sac, and becomes adherent to the previously calcified dentine. Calcification commences about the seventeenth week of fetal life, in the temporary incisors, and in the remaining temporary teeth during the seventh month; in the first permanent molars