ANATOMY AND PHYSIOLOGY OF THE PERIODONTIUM Flashcards
also called “the attachment apparatus” or “the supporting tissues of the teeth.”
periodontium
- main function is to attach the tooth to the bone tissue of the jaws and to maintain the integrity of the surface of the masticatory mucosa of the oral cavity
periodontium
three zones of the oral mucosa
- masticatory mucosa
- specialized mucosa
- oral mucous membrane
consists of the gingiva and covering of the hard palate
masticatory mucosa
covers the dorsum of the tongue
specialized mucosa
lines the remainder of the oral cavity. floor of the mouth, ventral side of the tongue, cheeks, lip, and soft palate
oral mucous membrane
the part of the oral mucosa that covers the alveolar process of the jaws and surrounds the cervical portion of the teeth.
gingiva
soft tissues that serves as a barrier which prevents microorganisms from entering the gingival connective tissue
gingiva
there is no mucogingival line present in the palate since the hard palate and the maxillary alveolar process are covered by the same type of masticatory mucosa
gingiva
also known as Unattached gingiva, Free gingiva
marginal gingiva
coral pink, has a dull surface and firm consistency. It extends from the gingival margin to the gingival groove
marginal gingiva
the terminal edge or border of the gingiva surrounding the teeth in collar like fashion
marginal gingiva
In 50% of the cases, it is demarcated from the adjacent, attached gingiva by a shallow linear depression,
free gingival groove
It may be separated from the tooth surface with a periodontal probe.
free gingival groove
positioned at a level corresponding to the level of the CEJ
free gingival groove
only present in 30-40% of adults
free gingival groove
The shallow crevice or space around the tooth bounded by the surface of the tooth on one side and the epithelium lining the free margin of the gingiva on the other.
gingival sulcus
it is v shaped
gingival sulcus
the so-called probing depth of a clinically normal gingival sulcus in humans
2-3mm
in pristine conditions, this does NOT exist.
gingival sulcus
After completed tooth eruption, the free gingival margin is located on the enamel surface is
approximately 1.5-2mm coronal to the CEJ.
attached firmly to alveolar bone and varies in width
attached gingiva
extends from the free gingival groove unto the mucogingival junction.
attached gingiva
it is firm, resilient, and tightly bound to the underlying periosteum of alveolar bone.
attached gingiva
attached gingiva is demarcated from the adjacent loose and moveable alveolar mucosa by the
mucogingival junction
the distance between the mucogingival junction and the projection on the external surface of the bottom of the gingival sulcus or the periodontal pocket.
width of the attached gingiva
the attached gingiva is greatest at
the incisor region
the attached gingiva is less in the
posterior segment
the width of the attached gingiva is least in the
premolar area
changed in the width of the attached gingiva is caused by
modifications in the position of its coronal end.
it increases with age and supraerupted teeth.
attached gingiva
palatal surface in the maxilla blends imperceptibly with the palatal mucosa.
attached gingiva
physiologically, if attached gingiva is absent
food can cause friction on mucosa which will lead to recession.
Occupies the gingival embrasure, which is the interproximal space beneath the area of tooth contact
interdental gingiva
can be pyramidal or have a “col” shape
interdental gingiva
the tip on one papilla is located immediately beneath the contact point
pyramidal
presents a valleylike depression that connects a facial and lingual papilla and conforms to the shape of the inter proximal contact.
col
compared to an orange peel
gingiva (Stippling)
varies with age and is absent in infancy, appears in some children at about 5 years of age, increases until adulthood, and frequently begins to disappear in old age
stippling
feature of a healthy gingiva
stippling
reduction or loss of this is a common sign of gingival disease.
stippling
Microorganisms are present and could be still inflamed.
clinically healthy gingiva
-Marginal gingiva is scalloped, following the CEJ
-posterior, less scalloping, fills up the embrasures
-closely adapted to tooth structure
-consistency (firm and immobility for attached gingiva); -presence of stippling (orange peel appearance which is present in 40-60% of population
-dependent on rete pegs)
clinically healthy gingiva
three different areas of the gingival epithelium
-oral epithelium
- sulcular epithelium
- junctional epthelium
area of the gingival epthelium that faces the oral cavity
oral epithelium
area of the gingival epithelium that faces the tooth without being in contact with the tooth surface
sulcular epithelium
area of the gingival epithelium that provides the contact between the gingiva and the tooth.
junctional epithelium
The boundary between the oral epithelium and underlying connective tissue has
a wavy course
the connective tissue portions which project into the epithelium
connective tissue papilla
gingival epithelium is separated to each other by
epithelial ridges known as rete pegs
this is lacking in the junctional epithelium
rete pegs
these has rete pegs
oral and sulcular epithelium
lined by keratinized, stratified squamous epithelium
oral epithelium
4 layers of the oral epithelium
- Basal cell layer (stratum basale/germinativum)
- Spinous cell layer (stratum spinosum)
- Granular cell layer (stratum granulosum) 4. Keratinized cell layer (Stratum corneum
principal cell type of the oral epithelium
keratinocyte
keratinocyte in the oral epithelium undergoes
proliferation and differentiation
main function of this is to protect the deep structures while allowing a selective interchange with the oral environment
oral epithelium
takes place by mitosis in the basal layer and less frequently in the supra basal layers
proliferation of keratinocytes
involves the process of keratinization
differentiation of keratinocytes
morphologic changes in the oral epithelium
-Progressive flattening of the cell
-increased number of tonofilaments and intercellular junctions
-production of hyaline granules
-disappearance of nucleus.
Keratinocytes are attached with each other thru
desmosomes
also known as macula adherens
desmosomes
a cell structure specialized for cell to cell ADHESION
desmosome
consists of two adjoining hemidesmosomes
desmosomes
involved in the attachment of the epithelium to the underlying basement membrane
hemidesmosomes
absence of nuclei in the stratum corneum, has a well defined stratum granulosum
orthokeratinized
the stratum corneum contains pyknotic nuclei. Keratohyalin granules are dispersed, absence of stratum granulosum
parakeratinized
superficial cells has visible nuclei, absence of stratum granulosum and stratum corneum.
non-keratinized
stratum basale or stratum germinativum
basal cell layer
cells are either cylindric or cuboidal and are in contact with the basement membrane.
basal cell layer/basale/germinativum
possess the ability to divide (undergo mitotic cell division)
basal cell layer
considered as the progenitor cell compartment of the epithelium.
basal cell layer
has a very prominent round nucleus; organelles present
basal cell layer
stratum SPINosum
prickle cell layer