1 - Anatomy of the Periodontium Flashcards
1
Q
what is part of the normal periodontium
A
- gingiva
- tooth supporting structures
2
Q
what are tooth supporting structures
A
- PDL
- cementum
3 alveolar process
3
Q
what landmarks can you see at a cross section from B-L
A
sulcus, sulcular epithelium, junctional epithelium, cementum
4
Q
what determines the color of gingiva
A
blood flow, physiologic pigmentation (melanin)
5
Q
consistency of gingiva
A
firm with stippling sometimes
6
Q
contour of gingiva
A
inderdental papillae fill interprox w/ no recession
7
Q
three regions of gingiva
A
- oral or outer epithelium
- sulcular epithelium
- junctional epithelium
8
Q
what has no nuclei in stratum corneum, distinct stratum granulosum
A
orthokeratinized outer epi
9
Q
what has nuclei stratum corneum
A
parakeratinised outer epithelium
10
Q
whawt region of gingiva is non-keratinized
A
sulcular and junctional
11
Q
describe outer wall of sulcus
A
- has free gingival groove in 50% of patients
- keratinized
- unattached/free
12
Q
width of keratinized gingiva
A
distance from gingival margin to MGJ (but varies w/ location in mouth
13
Q
with of KG in maxilla
A
anterior > molar > premolar
14
Q
width of keratinized gingiva in facial mandible
A
anterior > molar > premolar
15
Q
width of keratinized gingiva in lingual mandible
A
molar > premolar > incisor
16
Q
why important to know width of keratinized gingiva?
A
we want to know where is it vulnerable for patients to get gingival recession. often occurs where keratinized gingiva is thinnest. nothing protecting underlying bone resulting in bone loss
17
Q
what is is. keratinized gingiva bound tightly to tooth and bone to be protective against recession
A
attached gingiva
18
Q
what extends from base of sulcus to MGJ
A
attached gingiva
19
Q
what thype of epithelium is attached gingiva
A
ortho or parakeratinized
20
Q
what is the width of attached gingiva
A
width of KG - probing depth = width of attached gingiva
21
Q
is stippling present in attached gingiva
A
depends on patient
22
Q
how to determine the width of attached gingiva
A
- probe
- measure w/ KG
- attached gingiva = KG - PD
23
Q
what is the differentce between KG and AG
A
attached = use perio probe, all is keratinized
not all keratnized is attached
24
Q
the coronal extent of ____ is mucogingival junction
A
alveolar mucosa
25
what type of epithelium is alveolar mucosa
non-keratinized epi
26
is alveolr mucosa bound to bone
no,; mobile
27
what is more red in color due to lack of keratinization and visibility of underlying BC
alveolar mucosa
28
what is a Line that demarcates the keratinized gingiva from the
alveolar mucosa
mucogingival juncition
29
what is an absence of attached gingiva (0 mm)
mucogingival defect
30
what happens when a probe penetrates to or beyong MGJ
mucogingival defect
31
what happens when probing depth >/= width of keratinized gingiva
MGJ
32
what are surgical corrections for mucogingival defects
1. CT graft
2. free gingival graft
33
what is a combination of GINGIVAL phenotype and BONE morphotype
periodontal phenotypes
34
what are the periodontal phenotypes
1. thin-scalloped
2. thick-flat
3. thick-scalloped
35
what periodontal phenotype is most likely to be risk of gingival reession
thin-scalloped
36
what periodontal phenotype is more likely to have more excessive gingival display, gummy smile
thick-flat
37
what shape dependent on the buccal lingual width of teeth
col: inderdental gingiva
38
shape of col on molars and premolar vs. anterior teeth
molars and premolar: saddle shaped
anterior: pyramidal shaped
39
depression between two interdental peaks
Col
40
where does periodontal disease start
where the toothbrush doesnt reach - interprodimal gingiva (col)
41
why does disease typically start at interproximal gingiva (col)
1. col is non-keratinized
2. more permeable
3. less resistant to bacterial ingress
42
what is the predominate cell in epithelium
keratinocyte
43
what produces pigmentation (melanin)
melanocyte
44
what are dentritic cells (antigen presenting cells) important in immune response
Langerhans cells
45
what extends from oral epi to junctional epi
sulcular eip
46
what is 1-2 mm in depth (in health), non-keratinized, and semi-permeable
sulcular epi
47
what forms attachment between gingival and tooth
junctional epi
48
what is the confluence of oral epi and REE at tooth eruption
junctional epi
49
what are the 2 strata of junctional epi
1. external basal lamina
2. internal basal lamina
50
what basal lamina of JE faces CT
external basal lamina
51
what basal lamina of JE attaches to tooth thru hemidesmosomal attachment
internal basal lamina
52
JE is coronal to or at level of CEJ when
prior to disease
53
what are the functions of JE
1. attachment to tooth
2. permeable barrier against bacteria
3. signal transduction
54
what allows diffusion of fluid and inflammatory cells to sulcus as host defense mech
permeable barrier against bacteria of JE
55
what allows hemidesmosomes to regulate gene expression, cell differentiation, an dproliferation of JE
signal transcution
56
what is the cell turnover rate of JE
rapid 1-6 days
57
what composes gingival CT lamina propria
collagen fibers (type1), fibroblasts, vessles, nerves, matrix, and inflammatory cells
reticular and papillary layer
58
what are 3 groups of collagen fibers
1. gingivodental
2. circular
3. transseptal
59
what collagen fiber:
Embedded into cementum of the tooth
Fan out coronally and apically
Extend to facial and lingual alveolar bone
gingivodental
60
what collargen fiber: encircle tooth
circular
61
what collagen fiber:
Extend between approximating teeth
Sometimes classified as principal fibers of the
Periodontal Ligament
transseptal
62
what is the function of gingival collagen fibers
Gingival fibers brace and
strengthen the gingiva
63
what does CAL stand for
clinical attachment loss
64
what occurs when there is loss of atachment in periodontitis
1. Connective tissue fibers are lost
2. Apical migration of junctional epithelium
3. Pocket formation
65
what is supracrestal tissue attachment
apico-coronal dimensions of JE and supracrestal CT attachment
(JE + CT)
66
what is the old term for supracrestal tissue attachment
biologic width
67
length of supracrestal tissue attachemtn
~2mm
68
Allow ___ between ___ to allow for "Supracrestal Attached Tissues" and sulcus depth.
3-4 mm; crown margin and bone crest
69
what is fluid that seeps from vessels in the gingival CT and flows outward into the sulcur
gingival crevicular fluid
70
does gingival crevicular fluid flow increase with increasing inflammation
YES
71
what do you think happens if you put a crown very close to bone
inflammation, recession, pain complaints by pt
72
function of gingival crevicular fluid
1. cleanse material from sulcus
2. improves adhesion of epi to tooth
3. contains antibodies
4. contains leukocytes
73
what is the CT that surrounds the root and connects it to alveolar bone
PDL
74
the PDL is continuous with ___ of the gingival CT
gingival collagen fibers
75
what are the terminal ends of principal PDL fibers which insert into cementum and bone
Sharpey's fibers
76
what type of bone lines the socket wall is is adjacent to PDL that contains the greatest number of Sharpey's fibers inserting into it
bundle bone
77
what are the 6 groups of principal collagen fibers of PDL
1. transseptal
2. alveolar crest
3. horizontal
4. oblique
5. apical
6. interradicular
78
what PDL fiber extends interproximally from tooth to adjacent tooth
transseptal
79
what PDL fiber extends from cementum just beneath the JE to alveolar crest
alveolar crest
80
what PDL fiber resists extrusion and lateral forces
alveolar crest
81
what PDL fiber extends at right angles from cementum to alveolar bone
horizontal fibers
82
what is the largest PDL collagen fiber gorup
oblique
83
what PDL fiber extends from cementum in a coronal direction obliquely to bone
oblique
84
what PDL fiber obtains the bear brunt of vertical masticatory forces
oblique
85
what PDL fiber is in the furcation area of multi-rooted teeth
interradicular
86
principle fibers of PDL are composed mainly of what
collagen type I
87
what are the connective tissue cells in PDL
fibroblasts (primary cell), cementoblasts, osteoblasts
88
what are the epithelial cells of PDL
epithelial cells of Malassez and remnants of HERS
89
remnants of HERS can result in what?
1. lateral periodontal cysts
2. PA cysts
3. cementicles
90
what are the cellular elements of PDL
1. immune cells
2. neurovascular cells
91
what are the immune cells of PDL
1. neutrophils
2. lymphocytes
3. macrophages
4. mast cells
5. eosinophils
92
what are the functions of PDL
1. soft tissue casing to protect vessels and nerves
2. transmission of occlusal forces to bone
3. attachment of teeth to bone
4. SHOCK ABSORPTION
5. progenitor cells
6. nutritional and sensory functions
93
what broad category of cells aid with formation/resorption of bone, cementum
progenitor cells
94
what are the progenitor cells
fibroblasts, cementoblasts, osteoblasts
95
fusion of root to bone is called what
ankylosis
96
what is the shape of PDL
hour glass
97
PDL [increses or decreases] with loss of function
DECREASES
98
PDL [increases of decreases] with increased forces
INCREASES (e.g. occlusal trauma)
99
average width of PDL
0.2 mm
100
what are the types of cementum
acellular (primary) and cellular (secondary)
101
what are the two sources of collagen fibers in cementum
1. extrinsic (Sharpey's fibers from PDL)
2. intrinsic (produced by cementoblasts within cementum)
102
what are the incremental lines in cementum
periods of rest in cementum formation
103
what is the inorganic content of cementum
45-50% HAP
104
what cementum is first formed? when?
acellular/primary cementum prior to complete eruption of tooth
105
what covers cervical 1/3rd of root
acellular/primary cementum
106
what cementum contains many Sharpey's fibers
acellular primary cementum
107
when is cellular/secondary cementun formed
after tooth reaches occlusal plane
108
what contains cementocytes in lacunae
cellular/secondary cementum
109
where is cellular/secondary cementum thinnest? thickest?
thinnest = coronal half
thickest = apical third
110
what cementum increases in thickness with age
celular (secondary) cementum
111
which cementum has fewer sharpey's fibers
cellular (secondary) cementum
112
what are the type of CEJs from most common to least common
cementum overlaps enamel -> butt joint -> cementum does not meet enamel
113
what is the clinical significance of the CEJ
can result in dentinal hypersensitivity especially when cementum does not meet enamel
114
what is the portion of maxilla and mandible which supports the tooth sockets
alveolar process
115
what disappears after tooth is loss
alveolar process
116
what does alveolar process consist of
1. alveolar bone proper
2. cancellous trabeculae
3. cortical bone plate
117
in tooth socket wall, what contains bundle bone
alveolar bone proper
118
in tooth socket wall, what contains perforations for blood vessels entering PDL
cribiform plate
119
in tooth socket wall, what is the dense cortical bone surrounding the socket and is a radiographic term
lamina dura
120
T/F: alveolar process CANNOT resorb after tooth extraction
FALSE. can resorb
121
what is the loss of bone overlying the root surface that does not involve the crestal bone
fenestration
122
what is it called when portion of root surface is exposed, and crestal bone is not intact
dehiscence (entire portion not window)
123
dehiscence predisposes to what
gingival recession
124
what are the cells of the alveolar process
1. osteoblasts
2. osteoclasts
3. osteocytes
4. osteoid
125
what produces organic matrix of bone
osteoblasts
126
what are bone resorptive cells
osteoclasts
127
what cells of alveolar process are found in lacunae
osteocytes
128
what cells of alveolar process are non-mineralized bone matrix
osteoid
129
gingival blood supply comes from what sources
1. vessels from PDL
2. supraperiosteal arterioles from alveolar process
3. arterioles from interdental septa
130
what are the effects of aging on perodontium
1. gingival recession
2. root surface caries
3. alveolar bone
4. wound healing after surgery
5. periodontitis
131
what is a cumulative effect over many years of inflammation and toothbrush trauma
gingival recession
132
does gingival recession occur during passive eruption
yes
133
is gingival recession an inevitable physiologic process of aging
NO
134
what is at increased risk due to recession and xerostomia related to medications
root surface caries
135
what is the exposure of teeth via apical migration of gingiva (recession)
passive eruption
136
what part of periodontium is affected with osteoporosis
alveolar bone
137
how is wound healing after surgery affected in regards to aging on the periodontium
delayed
138
is periodontitis more prevalent with increased age?
yes due to increased exposure compared to younger people
139
periodontitis is due to cumulative epxosure to what
plaque
140
is periodontitis due to increased risk for disease
NO!
141
what is each #
1. free/marginal gingiva
2. free gingival groove
3. keratinized gingiva
4. attached gingiva
5. mucogingival junction
6. alveolar mucosa
7. papilla
142
what is each letter
A = free gingival groove
B = sulcus
C = sulcular epi
D = oral epi
E = junctional epi
F = cementum
