Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BDS 2 > Tooth And Periodontal Anatomy > Flashcards

Tooth And Periodontal Anatomy Flashcards

1
Q

What is tooth sensibility and tooth vitality

A
  • Tooth sensibility is its in tact nerve supply

- tooth vitality is its blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where do roots generally lie on molars?

A

mesiobuccally
Upper: 2 buccal 1 palatal
Lower: 1 distal 1 mesial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what were the lines of defence of the root of a tooth to bacteria

A

-cementum surrounds all of the porous dentine until the apex (also stops bacteria and toxins exiting the pulp)
-pulp can deposit tertiary dentine to move pulp from infection
-pulp contains immune cells
-periapex acts as 2nd line defence
-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how wide should the periodontal ligament space be

A

0.2-0.3mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the PDL space sits between cementum and….

A

lamina dura

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what abnormalities can happen through tooth formation (3)

A

gemination - tooth attempts to split
fusion - 2 tooth (crown) germs adjacent fuse together
concretence- roots of adjacent teeth fuse via cementum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is gemination

A

where a tooth attempts to split in 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is fusion of teeth

A

where adjacent tooth germs fuse (crown)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is concretence

A

where the roots of adjacent teeth fuse at the cementum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is ‘dens in dente’

A

infolding of the outer dental material into the interior tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is dilaceration of a tooth

A

a sharp near 90 degree bend in the root or crown due to trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is Taurodontism

A

elarged pulp chambers
very low furcation
short roots
(cow teeth)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

describe the characteristics of amelogenesis and causation

A

very thin, grooved and pitted enamel that is discoloured and flakes off
due to defects in amelogenin gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe the characteristics of dentinogenesis and causation

A

small, soft, thin dentine with enlarged crowns/pulps and short roots
pulpal obliteration
hand in hand with osteogenesis imperfecta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is pulpal obliteration

A

hard deposits in pulp chamber remove contents of pulp and replace with hard tissue - dentine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are odontomas and when are they most likely

A

technically begin tumours
derived from odontogenic epithelium and produce tooth-like tissue around forming teeth
incidence 10-20 years old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

when do odontomas cause problems

A

Benign tumors of the bone

Eruption of secondary dentition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what types of odontoma can you get and where do they commonly occur

A

compound: large single mass of radiopaque tooth tissue (posterior mandible)
complex: lots of small denticles in a capsule and often occurs in the anterior maxilla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

when do odontomas stop devloping

A

when causative tooth stops devloping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is ICP

A

intercausal position - the position of the mandible where there is maximum intercuspation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

if a patient has an over-erupted tooth, what are some causes of this

A

no opposing teeth
opposing tooth has under contoured restoration
Periapical abscess

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

if a restoration has fallen out and there are no signs of recurrent caries, what is the likely cause of the failure of restoration?

A

poor occlusion with the restoration increased pressure on tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is CR

A

centric relation
Relation of the mandible to the maxilla when the condyles are seated in the midmost uppermost position in the glenoid fossa
It is a jaw position and has nothing to do with the teeth
It allows a range of movement ~25mm - when the condyles are fully seated in the glenoid fossa- This is a hinge movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

how far can we open out mouth before we leave CR

A

~25 mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is RCP

A

retruded contact position
The relation of the mandible to the maxilla when there is first contact between teeth whilst the mandible is in the glenoid fossa i./e in centric relation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

where do we usually find RCP?

A

on a posterior teeth, usually on just one side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

how do we find a patients RCP

A

ask them to put their tongue as far back along their palate

close their teeth very slowly until in contact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

how do we find a patients ICP

A

ask them to put their tongue as far back along their palate as possible
close down

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is protrusive excursion and how do we make a patient do this

A

this is where the mandible moves forward from ICP and up against the maxilla bringing the lower incisors infront of the upper incisors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what controls and affects protrusive excursion

A

the protrusive guidance (teeth involved)

the incisor classification controls this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is class I occlusion

A

ideal

where incisors have ideal angulation and the lower incisal edge sits on upper incisal cingulum plateau

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what is class II occlusion

A

where the angle of the upper incisors is not ideal
division 1 - proclined
division 2 - reclined

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is class III occlusion

A

where the lower anterior are proclined leading to the lower anterior being in front of the upper anterior in ICP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

where do we measure the classification of occlusion

A

in ICP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

how does Class II div 1 and 2 affect protrusive excursion

A

div 1 - shallower and longer, maybe posterior teeth involved

div 2 - steeper and shorter,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what occlusal class has negative overbite?

A

III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

in class III occlusion, where does protrusive guidance occur

A

posterior teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are the two classes of guidance for lateral excursion

A

canine guidance

group function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is the jaw split up into during lateral excursion

A

working side - side jaw is moving towards

non-working side - side jaw is moving away from

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

how do we find a patients lateral guidence

A

into ICP
keeping teeth together, move teeth to the working side
observe which teeth are in contact - guidance either canine or group function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

which guidance for lateral excursion is ideal and why

A

canine guidance
long roots
bulbous crown
circular roots to take sideways force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are non-working side contacts known as during lateral excursion

A

interferences

cause failed restorations and fractures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what teeth should separate during excursions

A

protrusive excursion - posterior teeth

lateral excursion - non-working side teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

how do we take an occlusal assessment

A
  1. ICP contacts
  2. RCP contacts
  3. Slide from RCP to ICP
  4. Anterior guidance teeth
  5. Lateral excursion teeth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what is horsehsoe articulating paper used for

A

only used for dentures

too thick and uncomfortable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what are some disadvantages of horseshoe articulating paper

A

too thick and uncomfortable

so thick that it can fill gaps in occlusion and make it seem as though there is occlusion where really there is a gap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

what should we use to check normal occlusion of most restorations and occlusions and when should we not use it

A

regular articulating paper

don’t use for detailed occlusal assessments (GHM paper) or dentures (horseshoe)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what is GHM paper and when is it used

A

very accurate articulating paper
19 microns thick
Used for occlusal assessment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

what is the thinnest occlusal assessing material

A

Shimstock foil 8 microns thick

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

how do we use shimshock

A

place it in between teeth - try pull it out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

how do we measure RCP contacts

A

Help patients into CR by putting fingers on the lower border of the mandible and thumbs on chin, allow patients to relax and move their jaw up and down until moving on the hinge, then slowly bring into occlusion to first contact.

52
Q

how do we measure the slide from RCP into ICP

A

large or small slide

53
Q

what is crossover interference

A

during extreme protrusive excursions, the lower teeth interfere with the upper teeth

54
Q

what do we measure and report when investigating protrusive excursion

A

which teeth are involved with GHM or shim stock
any posterior disocclusion - posterior teeth contacts during protrusion
any crossover interference - extreme protrusion causing lower teeth to meet upper

55
Q

what do we assess during lateral excursion assessment (2) and how

A

any non-working side occlusion
canine or group function
mark guidance with GHM or shimstock

56
Q

what occlusal checks do we make during restorations

A

BEFORE:

  • check involvement in occlusal positions
  • check involvement in guidance’s

AFTER:
-check that we have maintained the occlusions

57
Q

if we have a fractured restoration that was previously guiding, how do we restore this tooth in terms of its occlusion and why

A

provide restoration
ensure it has little/no involvement in guidance as this obviously put too much stress on the restoration
ensure it is still involved in ICP as if not, the opposing tooth will over-erupt

58
Q

what should we consider when changing occlusion due to failed restoration

A

if we remove contact during excursion for example, this may put extra stress on another guiding tooth causing more fractures

59
Q

what is pulp vitality

A

presence of a blood supply to the dental pulp (tooth is alive and cells are alive)

60
Q

what is pulp sensibility

A

ability of the A delta fibres in the dental pulp to respond to a stimulus (nerve supply)

61
Q

when may a patient have vitality but not sensibility

A

trauma

62
Q

why are vitality tests better than sensibility tests

A

nerve supply can be disrupted leading to false negatives

blood supply cannot be disrupted without the tooth dying so it is most reliability for the life of tooth

63
Q

what are 2 common sensibility tests

A

cold ethyl chloride test

electric pulp testing

64
Q

what are common vitality tests

A

laser doppler flowmetry and pulse oximetry

65
Q

do we generally do vitality or sensibility testing

A

sensibility as we assume if there is a nerve supply, there is also a blood supply
also much cheaper and requires less expensive equiptment

66
Q

where is the best place to place an ethyl chloride cotton wool bud

A

mid-labial (mid buccal) surface as this is most sensitive to tests

67
Q

what must we do when doing a cold sensibility test

A

test mid-labial surface for 15 seconds or until stimulated

test contralateral teeth to compare and see if negatives are due to enamel thickness

68
Q

if we get a negative or uncertain positive cold test, what do we do next

A

electric pulp test

69
Q

how much bone surrounds roots of permanent molars

A

1cm

70
Q

where is the most permeable surface of molar roots

A

mesial and distal surfaces

71
Q

what are the weekly stages of extraction pocket healing

A

immediate blood clotting, vasodilation, WBC
week 1: granulation tissue, neutrophils on top, bone resorption, epithelium proliferation
week 2: major epithelial growth to continuity, granulation maturation and osteoid formation
week 4: new bone formation
3 month : bone maturation

72
Q

what is ankylosis

A

where root of tooth is fused with alveola bone via cementum with reduced PDL space

73
Q

What are the tooth’s pain nerve fibres

A

A delta fibres

74
Q

if enamel is unsupported, what does this mean

A

reduced dentine underneath it so can fracture under pressure

75
Q

what is undercut

A

the distance between the largest bulbosity of the tooth and the depth of the sulcus below it

76
Q

where and when do patients get ‘flabby ridges’

A

if they have natural teeth against an edentulous area

often in anterior 1/4 of mouth

77
Q

what is embrasure

A

V shaped valley between adjacent teeth

can be occlusal, lingual/palatal or buccal

78
Q

Average length of maxillary and mandibular canines?

A

Maxillary 26.5mm

Mandibular 25.5mm

79
Q

what is the % structure of enamel

A

96% mineralized inorganic hydroxyapatite
1% organic
3% water

80
Q

describe the inorganic structure of enamel

A

hexagonal hydroxyapatite crystals rods 6 micrometres in diameter
perpendicular to tooth surface

81
Q

what is the average depth of enamel

A

2mm

82
Q

What are some characteristics of healthy gingiva

A

Knife edge margins
Stippled
Presence of papilla
No bleeding

83
Q

where should the junctional epithelium attach and what are its healthy characteristics

A

at the CEJ cemento-enamel junction

smooth and attached to PDL below

84
Q

how deep should the sulcus depth be around a healthy tooth

A

0.5-2mm

85
Q

what is the function of the JE

A

apply constant microbial challenge being porous allows GCF to defend against bacteria to recruit neutrophils
produce antimicrobial chemicals
high turnover leads to epithelial cells funnel towards sulcus preventing colonization
attach underlying PDL to the tooth enamel

86
Q

what is the most common enamel matrix protein

A

amelogenin

87
Q

what is molar-incisor hypo mineralization and what implications does this have

A

where we have more porous, less mineralised first molars and first incisors
more sensative to brush and more suspetable to decay and TSL

88
Q

what happens to the apex of a tooth as we age from young to adulthood

A

it goes from very wide, close to nearly closed allowing small blood vessels and nerves

89
Q

how is the JE attached to underlying connective tissue and enamel

A

hemidesmosomes

90
Q

what are some charatceristics of JE

A

flattened cells connected with hemidesmosomes to connective tissue and enamel
large intracellular space making porous
very rapid turnover

91
Q

what are some unfavourable characteristics of the pulp chamber

A

tight apical constriction : blood and lymph flow limited and easily disrupted, intrapulpal pressure
unyielding walls : limiting volume to accommodate pulp swelling = pain
surrounded by bone = infection often leads to bone loss

92
Q

what is the function of the dental pulp

A 
Allows for root development in immature teeth. 
Maintain lifelong tooth development.
Maintains desirable properties of dentine (elasticity) by supplying nutrition to the organic components of dentine.
Sensory function (nociception) – warning system 
Maintain a defensive/protective role against dental caries, trauma, TSL
93
Q

which pain receptors are found in the pulp and what are they responsible for

A

A delta fibres - sharp pain - found at peripheries (first to stimulate)
C fibres = dull pain - found centrally, deeper

94
Q

what types (and percentages of) collagen are in bone matrix

A

collagen I = 95%

collagen V = 5%

95
Q

explain the structure of bone

A

collagenous bone matrix (95% collagen I, 5% collagen V)
between fibres we find small uniform crystals of hydroxyapatite
Small amounts of non-collagenous proteins, some which are unique to calcified tissue (e.g. osteocalcin).
within bone we find adipose tissue - bone marrow

96
Q

what cells are found in bone

A

Osteoclast (Oc): Large multinucleated cells. Bone resorbing cells.
Osteoblast (Ob): Bone forming cells.
Osteocyte: Originate from osteoblasts which have become embedded in the bone matrix. Involved in sensing mechanical loads and Ca2+ homeostasis.
Bone lining cells. Originate from osteoblasts. Line quiescent periosteal and endosteal surfaces of bone .
Osteoprogenitor cells (stromal cells). Precursors of osteoblastic lineage. Mesenchymal stem cells are found in the bone marrow.

97
Q

what is the function and fate of osteoblasts (3)

A

deposit bone during remodelling and bone growth. eventually turn into:
bone lining cells = Line quiescent periosteal and endosteal surfaces of bone .
osteocytes = become embedded in the bone matrix. Involved in sensing mechanical loads and Ca2+ homeostasis.

98
Q

compare the structure of primary and reactionary dentine

A

organised parallel dentinal tubules in 1

disorganised dentinal tubules in 3

99
Q

describe the structure of the pulp-dentine interface

A 
dentine
predentine
odontoblast
cell free zone
cell rich zone
pulp
100
Q

explain the structure of odontoblasts and associated structure and their function

A

single cuboidal cells that line inside of pulp chamber
large thin odontoblast cell processes that invaginate dentine through dentinal tubules
A-delta fibres in close proximity and slightly in tubules to detect stimuli e.g. thermal, pressure
responsible for laying down reactionary dentine
create positive fluid pressure from cell body end preventing toxin/bacterial entry to tubules

101
Q

what cells detect bacteria in dentinal tubules

A

dendritic cells

102
Q

what cells are found at the dentine/pulp lining (3)

A

odontoblasts with processes
dendritic cells for immune response to stimuli
A delta nerve fibres to detect painful stimuli

103
Q

what is the function of odontoblast processess

A

form peritubular dentine and form dentinal tubules for innervation of tooth

104
Q

what are the 2 types of tertiary dentine and compare

A

reactionary dentine : primary odontoblasts secrete dentine in a very similar structure to primary dentine to distance pulpal chamber from incoming infection and bacteria - mild stimulus
reparative dentine: primary odontoblasts die, secondary odontoblasts organise at site and place dentine. Structure depends on how well odontoblasts organise and speed of deposition - stronger stimulus

105
Q

the faster reparative dentine is deposited…: (3)

A

The less sensitive to thermal, osmotic,evaporative stimuli
The more porous and impregnated with soft tissue which is prone to infection
Reduced or no tubular fluid

106
Q

in a healthy, non-sclerosed tooth, what temperatures cause pain on contact to enamel

A

above 45 degrees or below 27 degrees

107
Q

how do we know there must be innervation within dentine and throughout dentine

A

pain stimulus through temperature is felt before any change in temperature of the pulp due to conduction
dentine sensitivity is constant throughout whole depth of dentine

108
Q

how are odontoblasts innervated and how do we know this

A

odontoblasts are innervated by A delta fibres
1 nerve innervates 100 odontoblast processes
we know nerves innervate the processes as if we cut the nerve supply, processes shrink and if we re-supply innervation, the processes grow back

109
Q

why must there be other innervation than just odontoblast process fibres

A

not all processes go to ADJ so A delta fibres cannot innervate to ADJ
however there is sensativity throughout the length of dentine to ADJ

110
Q

what is axonal transport and how does this help us

A

axonal transport is injecting a fluorescent substance into the trigeminal ganglion
following the fibres and we can see they enter the inner dentine = dentine sensitivity

111
Q

how do we know than dentine permeability affects dentine sensitivity

A

if we remove the smear layer (layer covering dentinal tubules due to mechanical abrasion) the tooth becomes more porous AND more sensitive therefor permeability and sensitivity are related

112
Q

what is the hydrodynamic theory, explain

A

Dentinal fluid fills the tubules and is constantly flowing outwards.
If dentine is dried, liquid is taken out of the tubules and odontoblasts are pulled up through the tubules and this causes pain due to stimulation of associated A delta fibres
If liquids are applied with the same osmotic pressure, it doesn’t cause any change in the flow of the dentinal fluid
If a solution of sugar is added, this change in concentration will cause pain.

113
Q

what is dentine sensitivity and what causes this

A

exaggerated, transient response to non noxious stimulus and affects 57% of the population
caused by exposure of dentinal tubules due to a multitude of reasons:
trauma, TSL, caries, gingival recession

114
Q

give 4 reasons why dentine may become exposed

A

TSL
trauma
caries
gingival recession and cementum breakdown

115
Q

how is the PDL attached to the tooth

A

PDL fibres - sharpeys fibres
attach into the cementum on root surface
attach into the lamina dura surface of alveolar bone

116
Q

what is the lamina dura and what is another name of this

A

thin hard layer of bone that lines the socket of a tooth and that appears as a dense white line in radiography
aka - cribriform plate

117
Q

which of the teeth are most likely to have hypomineralization

A

first molars 6

118
Q

what can cause pitting of teeth

A

amelogenesis/dentinogenetic imperfecta
hypominerlaization
radiotherapy/chemotherapy

119
Q

how mineralized is cementum, dentine and enamel

A 
cementum = 55%
dentine = 65%
enamel = 96%
120
Q

what types of cementum do we find

A

at the top of the root, acellular cementum

at the apex we find cellular cementum

121
Q

which teeth have 5 cusps

A

lower 6 - first teeth to erupt at 6 years old

122
Q

on the lower 6, where are the cusps situated

A

3 buccally getting smaller distaly

2 lingually

123
Q

which is the smallest premolar

A

lower 4 resembles canine with large buccal cusp

124
Q

which is the only anterior teeth with 2 roots

A

upper 4

125
Q

how many roots do the lower molars have

A

2 - 1 mesial and 1 distal

126
Q

how many roots do the maxillary molars have

A

3 - 2 buccal and 1 palatal

BDS 2 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions