Tooth supporting structures Flashcards
Gingival unit contain what
Free gingiva, attached gingiva, alveolar mucosa
Attachment unit contain what
cementum, alveolar bone, periodontal ligament
Masticatory mucosa function
Absorb the pressure while grinding the food
Masticatory mucosa histology
cover by thick epithelial and keratinized cells
Lining mucosa makes up what
Alveolar mucosa
Where Free gingiva start and end
extends from gingival margin to the base of gingival sulcus
light pink
0.5-2mm in depth
Gingival sulcus
space between the free gingiva and tooth
Healthy sulcus is less than 2.5mm in depth
Gingival papilla
free gingiva located in the triangular interdental space
Sharp in anterior teeth
Blunt in posterior teeth
Shape of gingival papilla/interdental gingiva is affected by what?
Location of the contact area of the adjacent teeth
Shape of the interproximal surfaces of the adjacent teeth
CEJ of the adjacent teeth
Inner portion of gingival sulcus
Lined with nonkeratinized epithelium
Outer portion of gingival sulcus
Covered with keratinized epithelium
Where attached gingiva begins?
Base of gingival sulcus (gingival groove)
Attached gingiva
Extends apically from the base of the sulcus and attached to bone and cementum by a dense network of collagenous fibers
Colour of gingiva
varies from light to dark pink
may contain pigment
correlating to skin pigmentation
*Sharpey’s fibers
The end of the periodontal fibers that are embedded in alveolar bone and cementum is called sharpey fibers
extend from cementum to papillary area of the gingiva
pass out from cementum in small bundles
Transseptal group (fibers) and it function
Travels completely across interproximal space and attaches to adjacent tooth
Bind one tooth to another
What all the gingival fibers do
keep gingiva closely attached to tooth surface
prevent free gingiva peeled away
resist gingival recession
prevent apical migration of the epithelial attachment
Where Alveolar mucosa join the attached gingiva
mucogingival junction
Periodontal ligament and it function
tissue that surrounds the roots of the teeth connects them to alveolar bone
acts as a suspensory mechanism to prevent the root and bone abrading each other
Act as a hammock of live tissue whose fibers cushion the impact between tooth and bone on the exertion of pressure
Alveolar BONE
thin covering of compact bone that surrounds the teeth
has many small openings through which blood vessels, nerves and lymphatic vessels pass
Radiographically name for alveolar bone
Lamina dura
Function of attachment apparatus (Cementum, PDL, alveolar bone)
1) Supportive- maintain the support for the tooth in the
bone and prevent its movement
2) Nutritive
3) Formative- replace cementum, periodontal ligament and
alveolar bone, accomplished by specialized
cells call cementoblast, fibroblast and osteoblasts
4) Sensory
Different between cellular and acellular cementum
Cellular Acellular
Cementoblast embedded free of
in the cementum embedded cementoblast
Covers apical portion of Always covers the cervical
the root and sometime third of the root and
form over acellular sometimes extends over
cementum almost all the root except
apical portion
Both types of cementum contain what?
Sharpey’s fibers of periodontal ligament (PDL)
Bundle bone
Applies when numerous layers of bone are added to the socket wall
Periodontal ligament fibers are arranged into 5 groups
Alveolar crest group
Horizontal group
Oblique group
Apical group
Interradicular group
Alveolar crest group
fibers extending from the cervical area of the tooth to alveolar crest
Horizontal group
Fibers running horizontally from the tooth to alveolar bone
Oblique group
Fibers running obliquely from the cementum to the bone
Apical group
Fibers radiating apically from the tooth to the bone
Interradicular group
Periodontal fibers that only present in root between multirooted teeth
What will periodontal fibers do if there is a pressure exerted on mesial surface
periodontal fibers on distal surface will compressed to allow more space between tooth and bone
Two forces are active within the mouth allow the movement of the tooth. What are the two forces?
Mesial drift- Allows tooth move forward within the oral cavity, thus closing the space lost from interproximal wear
Active eruption force- tooth migrate occlusally until it occludes with an antagonist (maxilla and mandibular)
List 4 supporting structure involved to maintain the tooth intact in the tooth socket
1) Gingival tissues
2) Alveolar bone
3) Cementum
4) Periodontal Ligament (PDL)
