The American text-book of operative dentistry / In contributions of eminent authorities. Ed. by Edward C. Kirk.

  • Edward Cameron Kirk
Date:
1900
Catalogue details

Licence: Public Domain Mark

Credit: The American text-book of operative dentistry / In contributions of eminent authorities. Ed. by Edward C. Kirk. 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.

    124/864 (page 122)
    dentin niati'ix. Tliis is lairly iinif'onn thn)U<;li()nt tlu; dentin. Tlie character of the tubuk's is diffcirent in tlie crown and root portions. In the crown tlie tnbides hrancli bnt little lhron<>h most of their course ; but in the outer j)art, close to the enamel, they branch and anastomose with each other (juitc freely. I i^. 102 shows a held of dentin just beneath the enamel, as seen with a high jM)wer, and shows the diameter of the tubides, their branching, and the amount of nuitrix between one tubule and the next. The relation of one tubule to each other is shown also in sections cut at right angles to their direction (Fig. 103). In the crown portion the tubules pass from the pulp chamber Fig. 104. Criiwn 111 a ninl.-ir, iiirsii)ili;-lal Sfctimi, shuwiiiL,' iiein.'tratKni ^f caru ;- : .1, carits )iLiiL-truUii,L; ilen- tin; />, line cif abrasion ; 7', iiiilji cIimiuIjlt. ;Ahoiit jn .) to the dento-enamel junction in sweeping curves, so as to enter the pulp chamber at right angles to the surface, and end next to the enamel at right angles to that surface. This produces S- or F-shaped \ or /] curves, which are known as the primary curves of the tubules. Through- out their course the tubules are not straight, but shoAV a great many wavy curves, known as the secondary curves. These appear as waves when seen in longitudinal sections, but are really the effect of an open spiral direction, as is seen by changing the focus of the microscojie in studying sections cut at right angles to the direction of the tubules.