Anatomy Flashcards
- Describe parts of the Periodontium
a. Gingiva
b. Cementum
c. Periodontal ligament
d. Alveolar bone
Gingiva
● Part of the oral mucosa that covers the alveolar process and surrounds the necks of the teeth
● Divided into distinct tissue, each are specialized in mechanical and microbial defense
o Marginal gingiva/unattached/free gingiva
▪ Free/unattached, cufflike tissue surrounding the teeth on the facial, lingual, and interproximal
▪ Most coronal portion of the gingiva
▪ Scalloped outline of teeth
o Gingival Sulcus
▪ Space formed by tooth and sulcular epithelium (lateral) and the coronal end of the junctional epithelium (apical)
▪ 1-3mm WNL, but can be deeper because of anatomic features
o Free gingival groove - only in 50% pts
▪ Divides free gingiva from attached gingiva
o Interdental gingiva (papilla)
▪ *Part of the free gingiva
▪ Immobile in health
▪ Occupies interdental/embrasure space apical to tooth contact
▪ Attach to the tooth by the junctional epithelium and connective tissue fibers
o Gingival Col
▪ The depression where the interproximal contact hit and the tissue makes a depression underneath
▪ Connects lingual and buccal interdental papilla
▪ Absent when teeth are not in contact (diastema or missing)
▪ Non-keratinized epithelium → susceptible to inflammation and disease
o Junctional epithelium
▪ It is a lining of the sulcus
▪ Non-keratinized epithelium surrounding and attaching to the tooth on one side, and the gingival connective tissue on the other size
▪ Base of the sulcus
▪ Very permeable to cells and fluids
▪ Serves as route of passage for fluid and cells going from the connective tissue into the sulcus for bacteria/bacterial products from sulcus to connective tissue
▪ When we go to scale or probe, this is easily penetrated but is completely restored (restores itself)
▪ Length is about 1mm
▪ Attached to tooth surface by epithelial attachment
▪ Gingival fiber braces the marginal gingiva against the tooth surface
● Gingival Fibers
provides support for marginal gingiva, including interdental papilla
o You are going to hear about periodontal fibers, gingiva fibers have to do with gingiva and periodontal fibers have to do with other aspects
o Types of gingival fibers
▪ Circumferential/circular - encircle each tooth in cufflike fashion within free gingiva
▪ Dentogingival fibers - embedded within the cementum, fan outwards into the attached gingiva
▪ Dentoperiosteal fibers - embedded in the same portion of the cementum as the dentogingival fibers
▪ Alveogingival fibers - inserted in the crest of the alveolar process and splay out through lamina propria into the free gingiva
▪ Transseptal fibers - embedded in the cementum, run horizontal from tooth to tooth (sometimes counted as part of the PDL)
● Attached Gingiva
o Attached to alveolar bone and cementum by connective tissue and epithelial attachment
o Boundaries are apically demarcated by the mucogingival junction; coronally demarcated by the base of the gingival sulcus
o Width varies from 1-9mm
▪ Widest in facial aspect of maxillary central incisor
▪ Narrowest on the mandibular facial premolar area
o NOT measured on palate
o Any changes in width of attached gingiva results from changes from the coronal end
o Measuring attached gingiva
▪ Measure amount of keratinized gingiva (gingival margin to mucogingival margin)
▪ Subtract the sulcus
▪ Difference = attached gingiva
o Lack of attached gingiva → recession
▪ Doesn’t grow back :( but surgical intervention can be done to improve things
● Alveolar Mucosa
o Red, smooth, and shiny is WNL
o Moveable tissue, loosely attached to underlying alveolar bone
o Thin, non-keratinized epithelium
o Separate from attached gingiva at the mucogingival junction
o Darker shade of red because rich blood supply
● Mucogingival Junction (MGJ)
o Thin visible line where pink keratinized gingiva meets the more vascular alveolar mucosa
o Found in maxillofacial and the mandibular facial and lingual
WTF is Edamatous?
Loss of tissue and fliuid buildup
Cementum
● Calcified connective tissue covering roots
● Least mineralized of the calcified tissues 🡪 45-50% Hydroxyapatite
● Function: attach fibers of the PDL to the tooth (like cement)
● No blood, lymph, innervation
● Continuously deposited in the apical area of the tooth throughout life
● Cemento-enamel junction - important to know for scaling/root planing
● Exposed cementum
o Rough surface texture facilitates plaque adherence
o Porosities facilitate attachment of calculus
o Porosities facilitate absorption of bacterial enzymes (i.e., endotoxin)
o Smear layer inhibits attachment of connective tissue
