tissues that surround, support and are attached to the teeth
What are the tissues of the periodontium
Gingiva
Cementum
Pdl
Alveolar bone
Underlying the gingiva is the __________ which is the ________
lamina propria
connective tissue part of the gingiva
Gingival crevicular fluid is fluid that seeps from the _________ and increases in the presence of ________
underlying connective tissue
gingival inflammation, tooth brushing and mastication
The width of attached gingiva is the distance between the
mucogingival junction and the bottom of the pocket or sulcus
The with of attached gingiva in the incisor and molar areas is about _______ wide and about ______ wide in the premolar areas
3 to 4 mm
2 mm
In general we would like to see at least _______ of attached gingiva
1-2mm
There is a facial papilla and a lingual papilla, connected by a
col
Is col non keratinized or keratinized?
Non keratinized
What kind of tissue is the periodontal ligament
soft connective tissue
Periodontal ligament is composed of _______ that attach the ________ on one side to the ______ on the other side and also known as _________
fiber bundles
root cementum
alveolar bone
Sharpey’s fibers
Periodontal ligament functions to
–Support the tooth
–Provide sensory feeling
–Provide nutrition by-way-of blood vessels–Provide cells to build and maintain cementum and alveolar bone
– Provide cells to resorb cementum and alveolar bone
Cementum has it's own blood supply
False
Alveolar bone is the bone that _______ and also known as ______
surrounds and supports the roots of the teeth
alveolar bone proper and the cribriform plate
What are the two layers of alveolar bone
Outside cortical or compact bone
Inside cancellous
Nerve supply to the periodontium occurs by-way-of branches of the _________ nerve with maxillary innervation via the _______ and the mandibular innervation via the ______
trigeminal
second branch (superior alveolar nerve)
third branch (inferior alveolar nerve)
Maxillary ginvigival innervation includes what nerves
superior alveolar nerves-(anterior, middle, posterior) infraorbital, greater palatine and nasopalatine nerves
Mandibular ginvigival innervation includes what nerves
Only the cells in the _______ layer undergo mitosis
basal cell
Nonkeratinized sulcular and junctional epithelium consist of what 3 layers
–Superficial cell layer
–Prickle cell layer (Intermediate)
–Basal cell layer
The gingival epithelium is joined to the underlying connective tissue at the basement membrane by a _______
basal lamina
The basal lamina consists of a what two layers
lamina lucida and lamina densa
____________ from the basal epithelial cells connect to the basal lamina
Hemidesmosomes
Crevicular fluid functions to
cleanse the sulcus and has antimicrobial(white blood cells) and immune(antibodies) properties
What kind of cells does the gingival crevicular contain
Inflammatory cells (92% of the gingival crevicular fluid consists of polymorphonuclear leukocytes and other white blood cells) lysosomal enzymes, and other by-products of the inflammatory process such as enzymes and cytokines
What is the length of the junctional epithelium
about 1mm
The junctional epithelium is attached to the enamel and cementum via _________
hemidesmosomes
What is the major importance of the junctional epithelium
Barrier to stop bacteria from entering the body
As we age what direction does teeth move
Mesially
The junctional epithelium has what 2 layers,
the basal cell layer and the prickle cell layer
_________ and the ________ are part of the dentogingival unit
Junctional epithelium
gingival fibers
Name the principal gingival fiber bundles
Dentogingival fibers
Alveologingival fibers
Dentoperiosteal fibers
Circular fibers
Transeptal fibers
Where are the Dentogingival fibers
radiate from the cementum into the free gingiva and attached gingiva to support the gingiva against the tooth
Where are the Alveologingival fibers
radiate from the periosteum into the attached gingiva to attach the gingiva to the bone
Where are the Dentoperiosteal fibers located
run from the cementum across the alveolar crest to help protect the periodontal ligament and hold the tissue to the tooth
Where are the Circular fibers located
encircle the entire tooth coronal to the alveolar crest to help support the free gingiva
Where are Transeptal fibers located
span the interdental space inserting into the cementum on adjacent teeth and help to maintain the relationships between teeth
Where are the Intergingival fibers (secondary fibers) located
run mesiodistally in the connective tissue beneath the gingival epithelium to help support the attached gingiva
How thick is the periodontal ligament space
.25mm
The fibers of the periodontal ligament are primarily composed of _______ and classified into what 5 principal fiber bundles
Type I collagen fibers
Alveolar crest group
Horizontal group
Oblique group
Apical group
Interradicular fiber group
Where are the Alveolar crest group fibers located and what is the function
runs from cementum just below the CEJ to the crestal bone to help anchor tooth in socket and oppose lateral forces
Where are the Horizontal group fibers located and what is the function
runs from cementum to the alveolar bone in the coronal third of the root to help anchor tooth in socket and oppose tilting and rotational forces
Where are the Oblique group fibers located and what is the function
runs in an oblique direction from cementum to the alveolar bone to help anchor tooth in socket and oppose intrusive and rotational forces.
Which periodontal fiber groups are the largest
Oblique
Where are the Apical group fibers located and what is the function
runs from the apex of the root into the alveolar bone to help anchor tooth in socket and oppose extrusive and rotational forces
Where are the Interradicular fiber group located and what is the function
runs from the furcation of multirooted teeth and attach into the alveolar bone to help anchor tooth in socket and oppose intrusive, extrusive and rotational forces
What are some characteristics of acellular or primary cementum
is the first to be formed and covers the cervical 1/3 to 1/2 the root
Contains no cementocytes
Formed prior to closure of the apex
About 30 – 60 microns thick
What are some characteristics of cellular or secondary cementum
mainly in the apical 1/3 of the root
Contains cementocytes
Forms throughout life
About 150-200 microns thick
What is the percentage of Overlap – cementum overlaps enamel
60%
What is the percentage of Meet –cementum meets the enamel
30%
What is the percentage of Gap-
10%
What is a dehiscence
–occurs where the bone between the crest and fenestration is so thin that the bone at the crest may disappear altogether
What is a fenestration
(window) – may occur where roots are prominent and the overlying bone is thin
