oral surgery Flashcards
1
Q
what does an abscess ALWAYS have?
A
pus
2
Q
what might be inside of a cyst
A
fluid or pus
3
Q
what is a cyst?
A
pathological cavity having fluid or semi-fluid contents
4
Q
is a cyst created by the accumulation of pus?
A
no
5
Q
where do cysts most commonly appear in the body
A
jaw bones
6
Q
what is a fluid filled cavity created by the accumulation of pus?
A
abscess
7
Q
what is a cyst often lined with
A
epithelium
8
Q
why do cysts commonly form in the jaws?
A
because of the epithelial remnants left over from the development of teeth eg dental lamina
9
Q
what do we have remnants of epithelium in the jaws from?
A
- development of teeth
- fusion of pharyngeal arches
10
Q
why are cysts of the jaws often epithelial lined?
A
because of the epithelial remnants of teeth and pharyngeal arches
11
Q
are cysts always epithelial lined?
A
no
12
Q
what are radicular inflammatory cysts derived from?
A
root sheath of hertwig
13
Q
what classification is used for cysts of the head and neck?
A
WHO 2022 cyst classification
14
Q
what is the most common cyst in the head and neck?
A
radicular cyst
15
Q
what is a radicular cyst associated with
A
non-vital tooth
16
Q
where are radicular cysts seen
A
anterior maxilla
17
Q
how do cysts in the jaws form
A
- remnants lie in a little ball of dormant cells in the alveolar bone
- something triggers the ball of cells to start proliferation
- they get to a size where the growth exceeds the amount of nutrition available so the central cells die
- the peripheral cells continue to proliferate while the cells in the middle undergo apoptosis
18
Q
what is usually the trigger for epithelial remnants that form cysts to being proliferation
A
bacterial infection
19
Q
what does the pressure of the expanding cyst cause on the neighbouring bone?
A
osteoclastic stimulation –> resorption
20
Q
what type of pressure allows a cyst to expand?
A
hydrostatic pressure
21
Q
what can happen if an expanding cyst is close to the buccal plate or palatal shelf?
A
erosion of overlying cortex
22
Q
what happens if a cyst erodes through the overlying cortex
A
can perforate through the mucosa
23
Q
what drives the expansion of a cyst
A
hydrostatic fluid
24
Q
what can a cyst present in the mouth as if eroded through the overlying cortex
A
- expansion of mucosa
- soft to touch - fluctuant swelling
25
intraorally, on palpation how would you recognise a cyst?
soft swelling of mucosa
26
what happens if a cyst expands at a fast rate?
can erode through the mucosa - causing an opening like a sinus
27
what can happen if a cyst causes an opening like a sinus through the mucosa?
bacteria can get into the cyst cavity and cause infection
28
what will happen if a cyst becomes infected?
becomes symptomatic
29
when are cysts symptomatic
when they become infected - generally not until then
30
what sign can bony expansion of a cyst cause intraorally?
egg-shell crackling - bone breaks to the touch
31
how are asymptomatic cysts often found
chance finding on a radiograph
32
what intraoral sign of a cyst will there be if there is only mucosa overlying it and no bone?
fluctuant swelling - soft to the touch
33
what may be a dental sign of cysts
- missing teeth
- carious teeth
- fractured teeth
- discoloured teeth
- loose teeth
34
why might teeth tilt because of a cyst
the pressure of the underlying cyst pushes the tooth out of the way
35
why might a cyst cause teeth to be loose?
underlying cyst may cause bone loss around the adjacent teeth
36
what is the name for swelling putting pressure on the alveolar nerve?
mental hypoaethesia
37
what percussion sound will a tooth associated with a cyst make
hollow sound
38
when would pain occur with a cyst?
infection
39
what might be a sign of a very large cyst taking over a large portion of the mandibular bone
pathological fracture
40
how would you know if a cyst is slow growing?
the body will form extra layers of bone over the top of the cyst to try and wall off the hydrostatic pressure
41
what 4 investigations would be made for a cyst
- vitality testing of teeth
- radiographs
- aspiration of contents
- biopsy
42
what radiographs would be taken for a cyst of the jaws
- DPT in first instance
- supplement with CBCT
43
what syringe and needle should be used to aspirate the contents of a cyst
10-20ml, wide bore needle
44
should LA be given before aspirating a cyst?
yes
45
what would cyst contents being clear with crystallisation that sparkles indicate?
inflammatory radicular cyst
46
what would cyst contents being clear with crystallisation that sparkles indicate?
inflammatory radicular cyst
47
what could blood in the contents of cyst indicate?
intra-alveolar vascular lesion
48
why would a biopsy of a cyst be taken
- establish which type
- rule out tumours
49
why is a cyst called "cyst-like radiolucency" clinically?
cannot call it a cyst before a biopsy confirms it
50
what are the management aims of a cyst?
- eradicate pathology entirely
- minimise surgical damage
- restore function as quickly as possible
51
what is the treatment of choice for a cyst
enucleation
52
what are the Tx options for a cyst
- marsupialisation
- enucleation
- both
- en bloc resection
- partial resection
53
how does a clinician decide between enucleation or marsupialisation
- type
- size
- site
- general medical status (for GA)
54
what can marsupialisation be in combination with if we want to preserve teeth involved with a cyst
peri-radicular surgery
55
what is enucleation
complete removal of cyst and lining
56
how does the body heal after enucleation
- large bony cavity fills with blood clot
- blood clot liquifies
- is replaced by granulation tissue
- replaced by bone
57
how long does healing after enucleation take
several months
58
following enucleation, how can closure be achieved?
- primary closure
- secondary closure
59
how is primary closure of a cyst done after enucleation
suturing the cavity over
60
how is secondary closure of a cyst done after enucleation
packing the defect, then replacing subsequent packs until the granulation tissue fills the base of the defect to the top
61
how is primary or secondary closure chosen after enucleation?
size of the cyst
adjacent vitality of teeth
any useful teeth in area
62
how would you plan the flap when undertaking enucleation
so it doesnt directly overly the osteotomy site - raise flap away from the cyst
63
how is a cyst accessed if there is still overlying bone
raise flap
osteotomise the site
64
how is the cyst/cyst lining removed from the defect
curettage
65
how should the sutures be places after enucleation of a cyst
so they are far away from the osteotomy site
66
why do we try and eliminate dead space when treating a cyst
- reduce reactionary haemorrhage
- reduce post-op infection
67
how does post-op infection happen if dead space is left when treating a cyst
the initial blood clot liquifies creating a very nutrient rich source for bacteria
68
how does a drain placement help with dead space after enucleation of a cyst
the vacuum sucks down the overlying mucosa to minimise the amount of dead space
69
other than dead space, what else does placing a drain after enucleation help with
reactionary haemorrhage as reduces the volume of blood clot that fills the space
70
why would a clinician choose to collapse the walls of the cavity after enucleation
converts the cavity shape into a larger shape that mucosa can fall over more easily, minimising the dead space
71
how can a clinician eliminate dead space after enucleation of a cyst
- biological materials
- layered soft tissue closure
- drain placement
- collapse cavity walls
72
what can a clinician use to fill the space after enucleation of a cyst
- pts own bone
- bone graft
- pts own muscles
73
what is the layered soft tissue closure post-enucleation of a cyst
suturing muscle into the area
74
is layered soft tissue closure post-enucleation of a cyst commonly done
no
75
what are the advantages of enucleation of a cyst
- complete removal for histology
- once primary closure, heals well without complication
76
what are the disadvantages of enucleation of a cyst
- large dead space - infection
- recurrence if incomplete removal of lining
- damage to adjacent structures
- weakening of the bone
77
what may be damaged during enucleation of a cyst
- teeth
- antrum
- nerves eg IAN
78
what may happen if a very large cyst is enucleated
pathological fracture risk
79
what is marsupialisation
create a window into the cyst lining to allow shrinkage of the lesion
80
how is a cyst marsupialised
the raised flap is sutured to the remaining lining
81
when is marsupialisation the treatment of choice for a cyst
when there is a very large cyst with multiple health teeth
82
what type of pt might marsupialisation be chosen for regardless of the cyst
older/ frail pt
83
what is a 'useful' tooth that may cause the clinician to choose marsupialisation over enucleation?
tooth that can erupt through the space where the cyst is eg canine, incisor
84
in marsupialisation where should the flap be planned for
directly over the area of bone we want to remove
85
what might be used in marsupialisation to help reduce infection
acrylic bung
86
what might be used in marsupialisation to help reduce infection
acrylic bung
87
how does an acrylic bung help reduce infection after marsupialisation
blocks orifice to prevent food entering and encourage secondary closure
88
what type of closure is there in marsupialisation
secondary
89
what are the advantages of marsupialisation
- avoids path fracture
- good for MH compromised pts that cant have GA
- avoids damage to adjacent structures
- allows useful teeth to erupt
90
what are the disadvantages of marsupialisation
- can close early causing recurrence
- repeat visits over long period
- manual dexterity and compliance needed from pt
- cannot get definite diagnosis
91
why might a cyst close prematurely when using marsupialisation
pt non-compliant with bung
92
why cant we get the full diagnosis when using marsupialisation
lining isnt entirely removed for pathology
93
what origin are radicular cyst
inflammatory
94
what % of dental cysts do radicular cysts make up
60
95
what % of dental cysts do radicular cysts make up
60
96
where on a non-vital tooth does a radicular cyst affect
apex
97
what % of radicular cyst can turn out to be a residual cyst
20
98
name 2 collateral cyst
paradental cyst
mandibular buccal bifurcation cyst
99
what is the incidence of radicular cysts
60-75%
100
what is the incidence of dentigerous cysts
10-15%
101
what is the incidence of a keratocyst
5-10%
102
what is the incidence of paradental cysts
3-5%
103
what is the incidence of gingival/lateral periodontal cysts
<1%
104
what is the incidence of a nasopalatine cyst
5-10%
105
what is a residual cyst
area of a cyst where the associated tooth has been extracted
106
what is the Tx for radicular cyst
enucleation with either XLA of tooth or apicectomy following RCT
107
how are lateral cysts and residual cysts treated
enucleation with either XLA of tooth or apicectomy following RCT
108
what is the Tx if a radicular cyst is really big and compromised adjacent teeth
marsupialisation +/- enucleation
109
how is a paradental cyst treated
enucleation + XLA of 8 if impacted
110
name 5 developmental cysts
- dentigerous
- eruption
- keratocyst
- lateral periodontal
- gingival
111
where does a dentigerous cyst form
around the crown of unerupted teeth
112
what does a dentigerous cyst form from
remnants of the reduced enamel epithelium
113
where is a dentigerous cyst always attached to
ACJ
114
how is a dentigerous cyst treated for an 8
enucleation and removal of associated tooth
115
how is a dentigerous tooth treated for any other tooth than an 8
marsupialisation and align tooth with ortho
116
what is a sign of a CHRONIC cyst
well defined corticated margins
117
what does no lamina dura indicate with a cyst
acute problem
118
what should the pt be told about long term outcome if marsupialisation is carried out
defect is often left in the bone
119
what is the Tx for a keratocyst
enucleation and XLA of tooth
120
what should the clinician pay attention to when removing a keratocyst
remove all the lining --> high recurrence as daughter cysts in the lining
121
where do keratocysts commonly form
angle of the mandible
122
what does a keratocyst form from
dental lamina
123
what is the problem with enucleation and removing the lining of a keratocyst
lining is very fragile and forms in antero-posterior "finger-like" projections through the trabeculae bone
124
what is carnoys solution
fixative lining that floods the cavity to fix any of the lining thats left behind
125
is carnoys solution advocated? why?
no, can fix delicate structures eg IAN
126
what is cryotherapy in cyst removal?
where the cavity is flooded with sterile saline and the cryotherapy probe is inserted until it freezes
127
is cryotherapy advocated in cyst removal, why?
debatable - no evidence base
128
what should always follow removal of keratocysts? and why
- radiographic long term follow up
- high recurrence rate
129
how were keratocysts previously treated when regarded as odontogenic tumours?
en bloc resection
130
what does root resorption often indicate in terms of type of pathology
less likely it is a cyst and more likely to be a tumour
131
what should you do before managing a pathology where there is root resorption
biopsy to determine diagnosis - more likely to be a tumour
132
what is the other name for gorlin goltz syndrome
nevoid basal cell carcinoma
133
what does gorlin goltz syndrome cause?
development of multiple keratocytes
134
what inheritance pattern does gorlin goltz syndrome follow
autosomal dominant
135
what genetic mutation cause gorlin goltz syndrome
PTCH gene found on chromosome 9
136
what % of gorlin goltz pts have an odontogenic keratocyst
75%
137
what is the average age that a pt with gorlin goltz syndrome will develop keratocysts in their mandibel
19
138
what other bony anomalies does a pt with gorlin goltz have
rib and vertebrae
139
what other feature of dental significance do pts with gorlin goltz syndrome have
prognathic mandible
140
what does a lateral periodontal cyst develop associated to
vital tooth
141
how can you determine the difference between developmental and inflammatory cysts prior to surgery
vitality testing of teeth
142
what is the Tx of a gingival cyst
enucleation/ excision
143
what is the most common epithelial non-odontogenic (fissure) cyst
nasopalatine duct cyst
144
where does a nasopalatine duct cyst develop
incisive canal
145
what does a nasopalatine duct cyst for from
remnants of the fusion of the pharyngeal arches - sensory organ of jacobson
146
what symptom is characteristic of a nasopalatine duct cyst
salty taste
147
what type of radiolucency is often seen with a nasopalatine duct cyst
heart shaped
148
what is the Tx of a nasopalatine duct cyst
enucleation after establishing vitality of adjacent teeth
149
how would a nasopalatine duct cyst be accessed
full-thickness palatal envelope flap
150
where do nasolabial cysts form
in the nasolabial fold between the upper lip and cheek
151
what is the Tx of nasolabial cysts
marsupialisation
152
name a non-epithelialise primary bone cyst
staphnes idiopathic bone cyst
153
what is staphnes idiopathic bone cyst
developmental abnormality
154
what causes the formation of staphnes defect
ectopic salivary tissues in the concavity of the mandible
155
which salivary gland causes staphnes defect
sublingual
156
what is the Tx for staphnes idiopathic bone cyst
none needed
157
name 2 bone cysts
- aneurysmal bone cyst
- solitary (haemorrhagic) bone cyst
158
what is the aetiology of aneurysmal bone cyst
unknown
159
what age group does aneurysmal bone cyst affect
10-20 years
160
where deos aneurysmal bone cyst appear
mandible
161
what can be seen histologically in an aneurysmal bone cyst
- mass of blood filled spaces with scattered giant cells
162
what does currettage of an aneurysmal bone cyst often cause
triggers healing
163
how is diagnosis of aneurysmal bone cyst determined
biopsy
164
how is a biopsy of an aneurysmal bone cyst taken
- raise flap
- make osteotomy
- currette out contents
165
who is a solitary bone cyst often seen in
teenagers
166
what gender are solitary bone cysts more common in
female
167
where are solitary bone cysts commonly found
mandible
168
what will be seen radiographically for solitary bone cysts
large radiolucency arching up between roots of teeth
169
what is the Tx of a solitary bone cyst
resolve spontaneously
170
what are solitary bone cysts thought to be caused by
bleed in the bone
171
what is an ameloblastoma
odontogenic tumour
172
what are ameloblastomas derived from
dental lamina
173
is ameloblastoma benign or malignant
benign
174
what age group are ameloblastomas most commonly seen in
40-50
175
what % of ameloblastomas are found in the mandible
80
176
what characteristics do ameloblastoma have
aggressive and invasive
177
what will be seen radiographically for an ameloblastoma
uni/multi-ocular, defined or diffuse edged, usually displaces adjacent structures
178
how are ameloblastomas diagnosed
biopsy under LA
179
what do we need from the biopsy to be able to diagnose ameloblastoma histologically
part of the lining
180
what are the three subtypes of ameloblastoma
- luminal
- intraluminal
- mural
181
how are the different subtypes of ameloblastoma differentiated from each other
according to the distribution of the proliferation of the epithelium
182
how are luminal and intraluminal ameloblastomas treated
conservatively
183
what mutation causes ameloblastoma
BRAF p. V600E mutations
184
what is the newest odontogenic lesion that is an epithelial odotogenic neoplasm called?
adenoid ameloblastoma
185
what is adenoid ameloblastoma composed of
cribriform architecture and duct-like structures frequently including dentinoid
186
what is dentinoid
dysplastic form of dentine
187
how many cases of adenoid ameloblastoma have been documented
40
188
what is the Tx for ameloblastoma (mural)
en bloc resection
