This slide describes in detail about the histology and structure of gingiva.

1. HISTOLOGY OF GINGIVA

3. • Based on the functional criteria,
Gingiva is classified under Masticatory
mucosa.
• Masticatory mucosa is bound to bone
and does not stretch. It bears forces
generated when food is chewed.

4. • The gingiva extends from the
dentogingival junction to the alveolar
mucosa. It is subject to the friction and
pressure of mastication.
• The stratified squamous epithelium may
be keratinized or nonkeratinized but most
often parakeratinized.
• Gingival epithelium is parakeratinized in
75% of population and non-keratinized in
10% of population.

5. NOTE -
• In orthokeratinized epithelium, the stratum
corneum contains flat tightly packed horny
scales and the nuclei are completely absent.
(15 % population)
• In parakeratinization, the cells retain pyknotic
and condensed nuclei and other partially
lysed cell organelles until they desquamate.
(75% population)
• In nonkeratinized epithelium, stratum
corneum is absent. (10%)

6. • The gingiva is limited on the outer surface of
both the jaws by mucogingival junction.
• Clinically, mucogingival junction is identified as
the junction between bright pink alveolar mucosa
and pale pink gingiva.

7. • The gingiva is normally pink in colour but sometimes it
may have a grayish tint.
• The colour depends in part on the surface, thickness and
in part on the pigmentation.
• The surface may be translucent or transparent, permitting
the colour of the underlying tissues to be seen.
• The reddish or pinkish tint is attributed to the colour given
to the underlying tissue by the blood vessels and the
circulating blood.
• Presence of melanin pigment in the epithelium may give it
a brown to black colouration. Pigmentation is most
abundant at the base of interdental papilla. It can be
increased in a number of pathologic states
COLOUR OF GINGIVA

8. Smoker’s melanosis is increased tissue
pigmentation, or darkening, due to irritation from
tobacco smoke.
CLINICAL

9. The gingiva can be divided into-
i) Free gingiva
ii) Attached gingiva
iii) Interdental papilla
FREE AND ATTACHED GINGIVA
• The dividing line between Free gingiva and attached gingiva is
the free gingival groove(not always visible macroscopically,
appears as a shallow V-shaped notch at a heavy epithelial
ridge in histological sections), which runs parallel to the
margin of the gingiva at a distance of 0.5 to 1.5 mm.
• The free gingival groove is probably caused by functional
impact on the free gingiva. In the absence of a sulcus, there is
no free gingiva.
MACROSCOPIC STRUCTURE OF GINGIVA

11. • The gingiva is characterized by a surface that is
stippled i.e. the portions of epithelium appear to be
elevated and between the elevations there are
shallow depressions. They probably are the
functional adaptations to the mechanical impacts.
• The disappearing of stippling is an indication
of a progressing gingivitis.

12. The degree of stippling vary in different individuals, there are also
differences according to age and sex of individuals.
Males tend to have more heavily stippled gingiva than females.

13. • The gingiva appears slightly depressed between the
adjacent teeth, corresponding to the depression on
the alveolar process between eminences of the
sockets. In these depressions, the gingiva sometimes
form slight vertical folds called interdental grooves.
• The interdental papilla is that part of the gingiva that
fills the space between two adjacent teeth. When
viewed from oral aspect, surface of papilla appears
triangular however in a 3-D view it appears tent
shaped between posterior teeth and pyramidal
between anterior teeth.
INTERDENTAL PAPILLAE

14. INTERDENTAL PAPILLA

15. When the interdental papilla is tent shaped, the oral and
vestibular areas are high, whereas the central part is like a
valley. The central concave area fits below the contact point,
and this depressed part of the interdental papilla is called the
col. Col (covered by non-keratinized epithelium) is more
vulnerable to the periodontal diseases.

16. Vestibular surface of gingiva of young adult

17. • The lamina propria of the gingiva consists of a dense connective
tissue that does not contain large vessels.
• Small number of lymphocytes, plasma cells, and macrophages are
present in the connective tissue subjacent to the sulcus and are
involved in defense and repair.
• The papillae of connective tissue are characteristically long,
slender and numerous.
• The tissues of lamina propria contain only few elastic fibers, and for
the most part are confined to the blood vessels. Other elastic fibers
known as oxytalan fibers are also present
LAMINA PROPRIA

18. Connective tissue papillae
The gingival fibers of the periodontal ligament enter
into the lamina propria, attaching the gingiva firmly to
the teeth. The gingiva is also immovable and firmly
attached to the periosteum of the alveolar bone.
Because of this arrangement, it is often referred to as
mucoperiosteum.
Here, a dense connective tissue, consisting of
coarse collagen bundles extends from the bone to
the lamina propria.

19. • The blood supply of the gingiva is derived chiefly from
the branches of the alveolar arteries.
• In the gingiva these branches anastomose with the
superficial branches of the arteries that supply the oral
and vestibular mucosa.
• The gingiva is well innervated.
BLOOD & NERVE SUPPLY

20. BIBLIOGRAPHY
• Organ's Oral Histology & Embryology
by G.S. Kumar
• Google images
• Images from slideshare.com
• Essentials of Oral Histology and
Embryology : A Clinical Approach