Page 518 - Atlas of Histology with Functional Correlations

excretory ducts from the lingual glands (11) form larger excretory ducts (6) that

often open into the tonsillar crypts (2, 8). Others open directly on the lingual
surface. Interspersed among the connective tissue of the lamina propria (5), the
adipose tissue (7), and the secretory mucous acini of the posterior lingual glands
(11) are skeletal muscle fibers (12) of the tongue.

FIGURE 13.11 ■ Lingual tonsils (transverse section). Stain: hematoxylin and
eosin. Low magnification.

FIGURE 13.12 | Dried Tooth (Longitudinal

Section)

This illustration shows a longitudinal section of a dried, nondecalcified, and

unstained tooth. The mineralized parts of a tooth are the enamel, dentin, and
cementum. Dentin (3) is covered by enamel (1) in the region that projects above
the gum. Enamel is not present at the root of the tooth, and dentin is covered by
cementum (6). Cementum (6) contains lacunae with the cementum-producing
cells called cementocytes and their connecting canaliculi. Dentin (3) surrounds

both the pulp cavity (5) and its extension into the root of the tooth as the root
canal (11). In life, the pulp cavity and root canal are filled with fine connective
tissue, fibroblasts, histiocytes, and dentin-forming cells, the odontoblasts. Blood

capillaries and nerves enter the pulp cavity (5) through an apical foramen (13)
at the tip of each root.

Dentin (3) exhibits wavy, parallel dentinal tubules. The earlier, or primary,

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