Figure 4-10.Structures of the gingiva.
portion is approximately 1 to 3 mm wide and forms the
soft tissue wall of the gingival sulcus next to the tooth.
Other structures of unattached gingiva include:
Gingival marginThe 1 mm narrow band of
gingiva that forms the immediate collar around
the base of the tooth. This area is first to show
symptoms of gingivitis.
Gingival sulcusArea between the unattached
gingiva and the tooth. Popcorn hulls get trapped
in this area.
Epithelial attachmentJoins the gingiva to the
Interdental papillaThe portion of the free
gingiva that fills the interproximal embrasures
below the contact areas of adjacent teeth. It
helps prevent food from packing between the
Attached Gingiva.Located apical to the free
gingiva on the labial and lingual aspects. It is firmly
fixed to the underlying bone of the cortical plates of the
Mucogingival Junction.-A line that separates
the attached gingiva from the lining mucosa.
Lining mucosa is found on the inside of the lips,
Incisors are named because they are used to incise
cheeks, vestibule, soft palate, and under the tongue. It
food. They are located in the front of the mouth and
consists of a thin, fragile tissue that is very vascular.
have sharp, thin edges for cutting. The lingual surface
Lining mucosa is brighter red in color than masticatory
can have a shovel-shaped appearance.
mucosa. Also included in the lining mucosa is alveolar
mucosa. It lies apical to the mucogingival junction and
is loosely attached.
This section describes the external features of the
teeth. A tooth is defined as one of the hard, bony
appendages that are borne on the jaws...and serve for
the seizing and mastication of food, as weapons of
offense and defense, etc.
In man and the lower
animals, the design of the teeth are a reflection of
eating habits. Animals, classified according to their
eating habits, are carnivorous (flesh eating),
herbivorous (plant eating), or omnivorous (eating
everything; both flesh and plant).
TYPES OF TEETH
Man is omnivorous, so his teeth are formed for
cutting, tearing, and grinding food. The human
permanent dentition is divided into four classes of
teeth based on appearance and function or position.
Figure 4-11 illustrates the types and working surfaces
of the four classes of teeth.