nullChapter 2
Periodontium
/Periodontal Tissues
(牙周组织)Chapter 2
Periodontium
/Periodontal Tissues
(牙周组织)IntroductionIntroductionThe gingiva(牙龈)
The periodontal ligament(牙周膜)
The alveolar process (牙槽突) The GingivaThe Gingivalocated around the necks of teeth
keratinized epithelium(角化上皮)
function during masticationThe periodontal ligamentThe periodontal ligamentsuspend the tooth in the socket
provide a cushion against occlusal forces
provide a delicate sense of touch and pressure
carry oxygen and nutritionThe alveolar processThe alveolar processthe bony extension of the mandible & maxilla
provide the necessary support for the teeth
an attachment for periodontal ligament fibers
compensate for tooth movementCementumCementuman attachment for periodontal ligament fibers
provide compensation for occlusal wear
protect the sensitive dentin ObjectiveObjectiveHistologic structures and function of the periodontal tissues
the gingiva
the periodontal ligament
the alveolar bone Part I GingivaPart I GingivaIntroductionIntroductionPosition: around the necks of teeth
Color: pinkSurface AnatomySurface AnatomyThe free gingiva(游离龈)
The attached gingiva(附着龈)
The interdental papilla(牙间乳头)Free gingivaAttached gingivaInterdental papillaFree GingivaFree GingivaBoundaries
Coronally: the gingival margin
Apically: the free gingival groove, 1.0~1.5mm
(游离龈沟,GG)Free GingivaFree GingivaGingival sulcus(龈沟) : 0.5~3mm
coronally: the gingival margin
bottomly: the junctional epithelium
the inner margin: the tooth surface
the outer surface: sulcular epitheliumGingiva sulcusGingiva sulcusAttached GingivaAttached GingivaPosition: between the free gingiva & the alveolar mucosa
the free gingiva: the free gingival groove
the alveolar mucosa: mucogingival junction nullStipple
orange peel appearance
the absence:
an initial sign of pathologyInterdental PapillaInterdental PapillaPosition: on the inter-proximal areas of the crowns on the labial and lingual surfaces
Shape: wedge-shaped nullThe col
interproximal to the vestibular and oral cavity surfaces of the interdental papilla
a concave area
anteriorly: like a pyramid
posteriorly: be flattened
plaque and calculus form: sign of inflammationHistological StructureHistological StructureThe surface epithelium
Lamina propria
rete epithelium ridgesThe surface epitheliumThe surface epitheliumthe margin of
the gingiva
the sulcular epithelium
the epithelium attachment
stratified squamous epitheliumnullkeratinized, parakeratinized, or nonkeratinizednull Gingival epithelium:
% of cases Surface cell Stratum granulosum
nucleus Keratinized 15 No Present Nonkeratinized 10 Yes None Parakeratinized 75 Partially None nullpigment granules: basal layer, melanocytenullThe sulcular epithelium
thin
lack keratinizationnullThe col
thin
nonkeratinized
extensions into the underlying connective tissuenullThe junctional epithelium
Definition:
a seal between the epithelium and the tooth, thinnullCharacteristics
the basement membrane is smoothnulla smaller tonofilament-to-cytoplasmic ratio
desmosomes is four times less - molecules of high molecular weight can migrate into the surface
rough endoplasmic reticulum & Golgi apparatus are highly developed - protein synthesis & glycosylation.nullthe attachment: cuticle & hemidesmosome
attachment plaque
tonofilaments
lamina lucida and lamina densa
cellular fibrilsnullhigh rate of cell turn over: the attachment between epithelium and tooth is dynamicnulldisturbance of the epithelial attachment: deepen of the gingival sulcus, form periodontal pocketnullthe relation between the gingiva and the tooth: changes constantly by age
20 or 30 year old: enamel
40 year old or later: cementoenamel junction
Elderly: cementumLamina PropriaLamina PropriaThe gingiva fibersnulldentogingival group: the cervical cementum - the lamina propria
alveologingival group: the alveolar crest - the lamina propria
circular group: circle the tooth
dentoperiosteal group: the cementum - the periosteum of the alveolar bone
transseptal group: the cementum - the cementum of the neighboring teeth nullelastic fibers: the walls of larger blood vessels
fibroblasts, macrophages, lymphocytes and plasma cells.Vascularity and NervesVascularity and Nerveshighly vascular: the branches of the alveolar arteriesnullwell innervated: touch endings, temperature and pain receptorsSummarySummaryThe free gingiva. The attached gingiva, and the interdental papilla
The free gingiva groove: separate the free and attached gingiva
The mucogingival junction:
separate the gingiva and the alveolar mucosanullThe gingival epithelium : keratinizednullThe epithelial attachment:
cuticle, hemidesmosomenullLamina propria: fiber groups - dentogingival, alveolar gingival, circular, dentoperiosteal, and transseptal
No submucosanullHighly vascular and well innervatedPeriodontal
LigamentPeriodontal
LigamentIntroductionIntroductionThe terms:
periodontal ligament / periodontal membrane
nullPosition: between the cementum and the alveolar bone proper
Thickness: 0.15~0.38mm, the thinnest part - the midroot nullThe collagen fiber bundles
Highly cellular
Rich nerve and blood supply.Histological StructureHistological Structuredense connective tissue
composed of fibers, cells, and stromaFibers Fibers Principal fibers
the bundles of collagenous fibers
between the cementum and alveolar bone proper nullSharpey’s fibers:
the embedded portions of principal fibers nullSpace fibers
the loose connective tissue
between the principal fiber bundles
contain the blood vessels, lymphatics, and nerves nullThe groups of the principal fiber bundles
the alveolar crest fibers
the horizontal fibers
the oblique fibers
the apical fibers
the interradicular fibersnull Principal Fibers Group name Location of attachment Function Alveolar crest Cervical root to alveolar crest of Resist vertical and
alveolar bone proper intrusive force Horizontal Midroot to adjacent alveolar Resist horizontal
bone proper and tipping force Oblique Apical one third of root to Resist vertical and
adjacent alveolar bone proper intrusive force Apical Apex of root to fundic alveolar Resist vertical forces
bone proper Interradicular Between roots to alveolar bone Resist vertical and
proper lateral movementnullOxytalan fibers
transmission electron microscopic observation
fine fibers nullthe special stains
part of the support system of the principal fibers.SummarySummaryPosition: between the root surface and the alveolar bone proper
Thickness: fairly constantnullPrincipal fibers
Alveolar crest
Horizontal
Oblique
Apical
InterradicularnullOxytalan fibers: fine fibers aid in the support of the ligamentNext Class HourNext Class HourThe cells, vascular, lymphatic, and neural supply of periodontal ligament
The histological structure of alveolar bonenull