WKI Sales Training Feb 2014

Chapter 7 • Head

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Labial mucosa

Vestibular (mucolabial) fold

Alveolar mucosa

Labial frenulum

Superior labial gingiva

I1 I2

C

PM

M

Vermilion border of lip

(A)

M

PM

PM

I1 I2 C

Inferior labial gingiva (gingiva proper) Alveolar mucosa (unattached gingiva)

Vestibular (mucolabial) fold

Labial mucosa

(B)

FIGURE 7.78. Oral vestibule and gingivae. A. The vestibule and gingivae of the maxilla are shown. B. The vestibule and gingivae of the mandible are shown. As the alveolar mucosa approaches the necks of the teeth, it changes in texture and color to become the gingiva proper. (Courtesy of Dr. B. Liebgott, Professor, Division of Anatomy, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.)

pink, stippled, and keratinizing. The alveolar mucosa (unattached gingiva) is normally shiny red and non-keratin- izing. The nerves and vessels supplying the gingiva, underly- ing alveolar bone, and periodontium (which surrounds the root[s] of a tooth, anchoring it to the tooth socket), are pre- sented in Fig. 7.79A & C. Teeth The chief functions of teeth are to: • Incise (cut), reduce, and mix food material with saliva during mastication (chewing). • Help sustain themselves in the tooth sockets by assisting the development and protection of the tissues that sup- port them. • Participate in articulation (distinct connected speech). The teeth are set in the tooth sockets and are used in mastica- tion and in assisting in articulation. A tooth is identified and described on the basis of whether it is deciduous (primary)

The principal muscles of the cheeks are the buccinators (Figs. 7.76). Numerous small buccal glands lie between the mucous membrane and the buccinators (Fig. 7.74A). Super- ficial to the buccinators are encapsulated collections of fat; these buccal fat-pads are proportionately much larger in infants, presumably to reinforce the cheeks and keep them from collapsing during sucking. The cheeks are supplied by buccal branches of the maxillary artery and innervated by buccal branches of the mandibular nerve. GINGIVAE The gingivae (gums) are composed of fibrous tissue covered with mucous membrane. The gingiva proper (attached gin- giva) is firmly attached to the alveolar processes of the man- dible and maxilla and the necks of the teeth (Figs. 7.76 and 7.78). The gingiva proper adjacent to the tongue is the supe- rior and inferior lingual gingivae, and that adjacent to the lips and cheeks is the maxillary and mandibular labial or buccal gingiva, respectively. The gingiva proper is normally

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