Dentogingival def.
From the cementum at the base of the gingival sulcus: found on facial, lingual, & interpoximal surfaces.
a. flares coronally into free gingiva
b. flares laterally into attached gingiva.
flares apically into periosteum
Dentogingival func.
Provides support to the gingiva.
Circular def.
Encircles the tooth within the free gingiva coronal to the alveolar crest.
Circular func.
Provides support and countour to the free gingiva.
Alveologingival def.
Extends from the periosteum of the alveolar crestal bone coronally into the connective tissue.
Alveologingival func.
Attaches the gingiva to the alveolar bone.
Alveolar crest def.
Originates from the cementum just under the CEJ and runs apically to insert into the alveolar crest.
Alveolar crest func.
Resists lateral movement, and keeps tooth in the socket.
Transeptal func.
Keeps teeth in alignment, protects the IP bone from inflammatory infiltrate; resistant to inflammation and will continuously reform when bond and fibers are destroyed.
Transeptal def.
Runs from the cementum of one tooth interpoximal to the cementum of the adjacent tooth.
Horizontal def.
Runs directly across PDL space; originates from cementum and runs at right angles and inserts into bone.
Horizontal func.
Opposes lateral forces.
Oblique def.
Found in the middle third of the root apical to the horizontal fibers; originates from cementum and runs diagonally into bone.
Oblique func.
Absorbs occlusal forces.
Apical func.
Originates from cementum of the apex of the root, spreading out apically and laterally into bone.
Apical def.
Resists tipping of the tooth.
Dentoperiosteal def.
Extends from the cementum apically over the alveolar crest into the periosteum.
Dentoperiosteal func.
Anchors tooth to the bone and protects PDL.
Interracdicular def.
From the crest of the interradicular septum extending to the cementum in the furcation areas.
Interracdicular func.
Resists the forces of luxation and tipping.
Alveolar bone
Cribiform plate
Hard compact bundle bone that lines the tooth socket.
Radiographically referred to as the lamina dura.
Supporting bone
Cancellous bone
Compact bone covers the alveolar process consists of buccal and lingual and cortical plates.
Periodontal ligament
In health, premits slight movement of the tooth under function within the socket.
One function is to provide suspensory mechanism attaching the alveolar bone to the tooth.
Acellular cementum
Formed before tooth eruption; found on the conronal 2/3 of the root; thinnest at CEJ; contains no cementocytes; does not lay down new cementum.
Cellular cementum
Covers apical third of root and furcations; thickest about 0.5mm