Oral Cavity Anatomy - Teeth Flashcards
(160 cards)
1
Q
What is the teeth anatomy arranged into?
A
Two dental arcades
2
Q
What are the two dental arcades associated with?
A
one is associated with the mandible and the other is associated with the incisive and maxillary bones
3
Q
Meaning of heterodont?
A
They have different types of teeth
4
Q
What types of teeth are there? (heterodont)
A
I, C, PM, M
(incisors, canines, pre-molars and molars)
5
Q
Mammals are…
A
diphyodont
6
Q
Meaning of diphyodont?
A
two types of teeth
7
Q
What are the two types of teeth that ‘diphyodonts’ have?
A
permanent and deciduous (I, C, PM only)
8
Q
For the teeth anatomy, what do we see in farm animals?
A
Diastema in farm animals AND RABBITS
9
Q
What equine, what is the diastema known as?
A
interdental space
10
Q
Diastema?
A
nothing is wrong, there is just a gap
11
Q
What anchors the tooth?
A
the root, it is anchored in a socket of bone called alveolar bone/alveolus
12
Q
What is the basic anatomy of the dental unit?
A
Crown, neck and then the root
13
Q
What is the neck of the tooth?
A
it is found between the crown and the root and is a constricted region just below the ginigival line
14
Q
What is the lamina dura also known as?
A
cribriform plate
15
Q
What is the lamina dura?
A
it is the thin shell of dense bone lining the alveoli
16
Q
What do teeth consist of?
A
Enamel, Dentine, Cementum and Pulp
17
Q
What is the pulp cavity?
A
The central space of the tooth containing pulp-soft tissue with nerves, vessels, lymphatics
18
Q
What is the periodontium?
A
The connective tissue that attaches root to the bone
19
Q
What are the four defined structures that the periodontal tissues include?
A
Gingiva, cementum, alveolar bone and the periodontal ligament
20
Q
What does the periodontal ligament do?
A
attaches the tooth to the bone
acts like a shock absorber
21
Q
What is the periodontal ligament?
A
interconnected interwoven bundle of fibres, anchored to the cementum and bone
22
Q
Name the two types of teeth:
A
Brachydont
Hypsodont
23
Q
Describe the Brachydont tooth:
A
smaller and low crowned
it has a constricted neck at the gum line
It has a true root
24
Q
What type of feeding is the brachydont suitable for?
A
feeding on soft diet; dogs, cats, ferrets and pig etc.
25
Describe the hypsodont tooth:
larger crown that can resist wear and tear
It has an open root or closed root
26
meaning of aradicular or radicular?
aradicular - open root
radicular - closed roots
27
type of feeding that hypsodont is suitable for and which animals have this type of tooth?
can resist the wear and tear of feeding on tough and fibrous diet as in ungulates; horse all permanent teeth (except canines) , ruminant cheek teeth, lagomorphs, tusks of pig (canine teeth)
28
What type of teeth do rabbits, guinea pigs, chinchillas and degus have?
They have aradicular hypsodont teeth
29
What is the hardest and most mineralised substance in the body?
Enamel
30
Is enamel cellular/acellular?
acellular
31
Because enamel is acellular, what does this mean?
it cannot regenerate
31
What is the exception to enamel's inability to regenerate?
swine canine teeth
32
describe the innervation/vascularisation of enamel:
no nerve or blood supply
33
For a brachydont, explain the enamel cover:
enamel covers the external surface of the crown
34
For a hypsodont, explain the enamel cover:
Covers the entire body of the tooth, but not the root
35
what does folding of the enamel create?
peripheral and infundibular enamel
36
What produces enamel?
ameloblasts
37
Histologically, what is enamel composed of?
long, slender rods
38
What is Dentin?
it forms the bulk of the tooth, it is hard, substance-like bone
39
what does dentin surround?
the pulp cavity
40
where does secondary dentin form?
forms at the periphery of exposed pulp cavity
41
How does dentin respond to trauma?
reparative or tertiary dentine is formed
42
What are odontoblasts?
the cells that continuously deposit the dentine
43
Where are odontoblasts found?
next to the pulp cavity
44
When are odontoblasts active?
they remain active throughout life
45
Describe the structure of the cementum?
it is the least hard of all, thin bonelike layer
46
what attaches the cementum to a bone and which bone is it attached to?
attached to the alveolar bone by the periodontal ligament
47
Describe the coverage of the cementum on a brachydont:
covers the root only
48
Describe where cementum is found on hypsodont teeth:
fills the infundibula of hypsodont teeth and covers the entire tooth
49
Why is equine cementum unique?
because it is vascular and innervated - and deposition continues throughout the life of the tooth
50
What is the gingiva/gums?
the name for the oral mucosa that covers the tooth
51
which one (of the four) of the periodontal tissues is normally seen in the mouth?
the gingiva/gums
52
where is the cementoenamel junction found?
borderline between the crown and root(s)
53
what is the CEJ?
The cementoenamel junction
54
what types of gingiva are there?
attached and free gingiva
55
What are attached gingiva attached to?
firmly attached to the underlying periosteum of the alveolar bone
56
where are free gingiva found?
adopted to the tooth surface
57
what is the gingival crevice also known as?
the sulcus
58
at what point in the mouth do the cells in the epithelium of the gum adhere to the tooth enamel?
at the gingival crevice
59
what forms a tight seal?
the adherence of the gingiva to the tooth
60
what are incisors adapted for?
for grasping, pinching, scratching and nipping
61
uses of canines?
'weapons' --> tearing flesh during hunting and fighting
62
what do premolars have that molars do not?
they have deciduous precursors
63
which premolars have deciduous precursors?
rostral cheek teeth
64
description of molars?
flattened and triangular with jagged edges
65
function of molars?
like serrated-edged blades
66
what teeth in particular are used for shearing and grinding?
upper P4 & lower M1
67
what is the vestibular surface of the tooth?
the surface of the tooth that is facing the vestibule/lips
(labial - incisors+canine
buccal - molars+premolars)
68
palatal?
refers to the lingual surface of the maxillary teeth
69
what is the lingual surface of the maxillary or mandibular tooth?
the surface facing the tongue
70
what collective name refers to the surfaces of the tooth face next to another tooth in the same row(?)
interproximal
70
What is the occlusal surface of the tooth?
the portion of the tooth that comes in contact or faces the opposite tooth (PM or M)
71
Meaning of the mesial surface?
surfaces of the incisor teeth that are toward the middle or median plane of the mouth
- rostral surface of the canine, premolar and molar teeth
71
Distal surface meaning?
surface of the incisor teeth that are AWAY FROM the middle or median plane of the mouth
- caudal surfaces of the canine, premolar and molar teeth
71
meaning of coronal?
the term relating toward the occlusal surface (crown of the tooth)
72
how many teeth do pigs have?
44 permanent teeth
72
meaning of apical?
towards the apex (root) of the tooth
73
what teeth are pigs born with?
needle teeth
74
which ones are the needle teeth?
the deciduous I3 and the canines
75
which tusk is larger?
lower one
76
describe the growth of the canines:
continuously grow
77
which teeth are the canine of a pig?
the tusk
78
what is the upper arcade of a pig?
I - 3 C - 1 P - 4 M - 3
79
What is the lower arcade of the pig?
same
80
what is found on the occlusal surface of the molars?
numerous tubercles
81
how many teeth do dogs have? what teeth are they missing?
42
the upper M3
82
Which teeth are the longest teeth in dogs?
canines
83
which are the carnassial teeth?
they are the biggest pair of shearing teeth
Upper PM4 & lower M1
84
upper and lower arcade of a dog?
I - 3 C - 1 P - 4 M - 2 (upper arcade)
3 1 4 3 (lower arcade)
85
in dogs, how does eruption time differ?
it differs between breeds
86
describe the root situation for the incisors of dogs?
all incisors have a single root
87
size of the root of the canine?
root of canine is large, it is larger than the crown
88
which teeth in dogs have two roots? What is the exception?
PMs and Ms
HOWEVER
PM1s have a SINGLE root
Upper PM4 + two upper M1, M2 have THREE roots
Lower M3 has SINGLE root
89
Describe ruminant teeth:
dental pad, NO upper incisors or canines
90
in ruminants, what are canines assimilated to?
incisors
91
the incisors and canines in ruminants are what type of tooth?
brachydont
92
the premolars and molars in ruminants are what type of tooth?
hypsodont
93
size of the diastema in ruminants?
large
94
describe the dental pad of ruminants:
thick stratum corneum (II) and well developed papillae of connective tissue
95
what is the stratum corneum?
the outermost layer of the epidermis
96
What happens to a horses hypsodont teeth?
they undergo continuous wear and slowly erupt
97
describe a horses' incisors:
high crowns with single root
98
describe the incisors in a younger horse:
they are curved
(convex on their labial aspect - concave on their lingual aspect)
99
describe a horses canine, in a mare:
often small and may not erupt
100
in a made, deciduous canines are often...
absent
101
in horses, describe the development of roots?
delayed
and they have closed roots
102
describe the large cheek teeth in a horse:
have a rough occlusal surface that acts as a grinding surface for fibrous feeds
103
which ones are the 'wolf teeth' in horses?
P1 - they are vestigial and often lacking
104
which teeth form a continuous surface in horses?
the premolars and the molars
105
PM2-PM4 and M1-M3 --> how many roots in upper and lower jaw?
3 roots in upper jaw and 2 roots in lower jaw
106
what separates the molars from the sinus in a horse? what does this result in?
a thin plate of alveolar bone - infection may easily spread to the sinus from tooth or alveolar abscesses
107
RMS?
rostral maxillary sinus
108
describe the cheek teeth on the maxillary arcade in a horse:
they have 2 infundibulae, which are deep infoldings of enamel filled with cementum in the center of the teeth
109
describe the mandibular cheek teeth in a horse:
same pattern of infoldings'invaginations as cheek teeth on the maxillary arcade BUT NO infundibulum
110
which teeth have complicated folding of enamel in horses?
the incisors and maxillary cheek teeth
111
what causes the appearance of the occlusal surface to change in horses?
as teeth continually erupt and wear down
112
tissues wear at...
varying rates
113
what is an infundibulum?
a cup/funnel shaped invagination of enamel
114
what does secondary dentin form in a horse?
it forms dental stars on worn surface of tooth
115
what does wear of a horses tooth result in?
causes the cup to get smaller and eventually disappear from all lower incisors, leaving the enamel spot in its place
116
what is infundibulum called colloquially (in teeth)?
a cup
117
what does infundibulum look like, and why?
looks like a dark mark, because food gets packed inside and turns black as it decays
118
what is infundibulum partly filled with and what does this result in?
partly filled with cement, leaving a small cavity
119
what does the infundibulum not connect with?
the pulp cavity
120
when secondary dentin is formed in the infundibulum, what does it overly?
pulp horn (dark brown D2)
121
How many roots do maxillary cheek teeth have? What are these roots?
3
2 buccal and 1 palatial
122
how many infundibulae do maxillary cheek teeth have? What are these called?
they have two: a mesial and distal infundibulum
123
how many roots do the madibular cheek teeth have and what are they?
has 2 roots, they are rostral and caudal roots
124
mandibular cheek teeth have no infundibulae, hence?
much narrower bucco-lingually
125
how many pulp horns do equine cheek teeth have?
either 5 or 6 pulp horns each
126
in which direction do pulp horn run?
run towards chewing surface
127
what order do rabbits belong to?
order of lagomorpha
128
why do rabbits belong to lagomorpha?
because of two small second incisors behind the maxillary incisors
129
in rabbits, what are the two small second incisors also known as?
peg teeth or Rudimentary incisor
130
how many incisor pairs do rabbits have?
three pairs of incisors: two upper and one lower
131
what shape do rabbits incisors have?
chisel shaped
132
describe the enamel distribution around the incisor of a rabbit:
it is not distributed uniformly around the tooth, the enamel is thicker on the vestibular aspect and thinner on the lingual aspect
133
what type of teeth are the cheek teeth and both incisors of a rabbit?
aradicular hypsodont
134
both incisors and cheek teeth in a rabbit are aradicular hypsodont, what does this mean?
meaning that teeth have long anatomic crown, erupt continuously and remain open rooted - they are elodont
135
meaning of elodont?
continuously growing, 'open rooted'
a type of tooth that increases in its height or length on the pulpal axis throughout life
136
what teeth do rabbits not have?
canine
137
rabbits have a typical herbivore occlusion, describe it:
horizontal occlusal surface with transverse enamel folds for shredding and grinding tough fibrous food
138
do rabbit have diastema?
yes
139
What artery is the terminal branch of the external carotid artery?
maxillary artery
140
describe the blood supply for the upper teeth:
supplied by the infraorbital artery
141
the infraorbital artery is a branch of which blood vessel?
maxillary artery
142
describe the blood supply for the lower teeth:
lower teeth are supplied by inferior alveolar artery (IAA)
143
Where does the inferior alveolar artery enter the mandible?
through the mandibular foramen into mandibular canal
144
IAA?
inferior alveolar artery
145
which nerve is cranial nerve 5? (CN V)
trigeminal nerve
146
what does the trigeminal nerve supply?
it supplies the sensory innervation of the teeth through its maxillary and mandibular divisions
147
describe the innervation of the upper incisor teeth:
innervated by infraorbital nerves (maxillary nerve)
148
where does the infraorbital nerve run?
runs in the infraorbital canal
149
describe the innervation of the mandibular teeth:
mandibular teeth are supplied by inferior alveolar nerves (mandibular nerve)
150
where does the inferior alveolar nerve (mandibular nerve) run?
runs in the mandibular canal
151
which nerve is the maxillary nerve?
infraorbital nerve
152
which nerve is the mandibular nerve?
the inferior alveolar nerve
153
which teeth don't have baby teeth?
molar
154
diphyodont?
just means that there are baby teeth which develop into adult teeth
155
