final exam Flashcards
(186 cards)
1
Q
Demographics of Osteomyelitis
A
Trauma or odontogenic infection history
Radiation and/or bisphosphonates
immunocompromised
conditions affecting jaw vascularity
2
Q
Facial bone osteomyelitis is different from long bone osteomyelitis, How?
A
facial bone is mixed infection (alpha strep and anaerobes), long bone is S. aureus
3
Q
In the Acute phase of Osteomyelitis, what laboratory should be order and what do you expect to see?
A
CBC: leukocytosis (increased WBC)
4
Q
Osteomyelitis seen in –x-ray. When do you see it and or do you see it? Why do you or don’t you see it on the x-ray?
A
Cortical involvement req for radiographic signs, lags behind clinical signs, req 30-60% destruction
acute: often WNL
Chronic: moth eaten
5
Q
How to treat dead bone ( sequestrum)?
A
sx and medical tx (sequestectomy)
6
Q
Surgical treatments of osteomyelitis are
A
sequestectomy, saucerization, decortication, segmental resection as LAST RESORT following multiple more conservative attempts
7
Q
Medical Treatment of Osteomyelitis is
A
begin empiric Abx based on gram stain
use results of C and S to determine more specific/ narrow Abx
IV Abx for 6 weeks
clindamycin used often, can penetrate bone
combo therpay
infectious dx consult
HBO therapy for chronic refactory cases
8
Q
Facial infection.. Know what is primary, secondary space
Primary maxillary spaces includes…
Primary Mandibular spaces includes…
Secondary facial spaces includes…..
A
Primary maxillary spaces includes…Canine, buccal, infratemporal
Primary Mandibular spaces includes…bucall, submental, sublingual, subman
Secondary facial spaces includes…..masserteric, pterygoman, superifical and deep temporal, lat pharyngeal, retropharyngeal, prevert
9
Q
When you do an I&D, you have seen puss ( alfredo sauce) what do you do with it beside suction it out?
Still don’t get it? Let me give you a hint, you need to send it to lab…
A
culture and sensitivty, gram stain can be used to guide early Abx
10
Q
if you were have a bad infection. How does bacteria / puss travel from tooth (maxillary or mandibular) to brain, to mediastinum, or close up trachea? (There is a slide in the lecture talking about common progression of facial space infection..) KNOW IT
A
pathway cards added
11
Q
Radiographic/ imaging work up for complex odontogenic infection are……
A
PA, pano, plain film
CT with contrast is best
12
Q
What is the definition of Ludwig’s Angina and what are the spaces involved?
A
Ludwig’s Angina is a fulminating, bilateral sublingual, submandibular, submental
and cervical infection or cellulitis displacing the tongue with potential** airway
obstruction.**
Life-threatening condition
Aetiology: Usually related to periapical abscess related to the lower molar teeth.
Airway is significantly narrowed causing severe respiratory distress.
Due to this situation, intubation during general anesthesia also becomes very challenging
13
Q
What is Cavernous sinus Thrombosis? Definition, pathophysiology and classic sign and symptom
A
- Serious condition that is recognised by the appearance of marked oedema and congestion of the eyelids and conjunctiva as a result of impaired venous drainage.
- This start as a unilateral and rapidly becoming bilateral.
- This condition is not as common as Ludwig’s Angina
- Hematogenous spread of infection from the jaw to the cavernous sinus may occur anteriorly via the inferior or superior opthalmic vein or posteriorly via emissary veins from the pterygoid plexus.
Direct extension through the opening in the cranial bones.
signs and symptoms on another card
14
Q
What’s the purpose of complete blood count with differential?
A
CBC (Complete Blood Count) with differential count – large outpouring of immature
granulocytes indicate severe infection.
15
Q
n early odontogenic acute infection, what types of bacteria is more dominant?
A
gram + aerobic
16
Q
How does facial infection spread?
A
- equally in all directions favors path of least R
- location determined by thickness of bone at apex and mm attatchments
- most present as vestibular abcess
- may begin as well delineated, self limited condition with potential to spread to major fascial planes
- can begin as PA osteitis or intrbony abcess and become cellulitis or abcess
17
Q
Classic signs of inflammation
A
rubor-red
calor-warm
tumor-swelling
dolore-pain
LOF- dif breathing, swallowing
18
Q
The main objective of performing I&D
A
Drainage of pus
Reduction of tissue tension
Increased blood flow
Increases delivery of host defenses
Obtain specimen for culture and sensitivity(C&S)
19
Q
Indications for antibiotic treatment of odontogenic infection are?
A
Rapidly progressive swelling
Diffuse swelling (cellulitis)
Fascial space involvement
Compromised host defenses
Severe pericoronitis
Osteomyelitis
Trauma
20
Q
What is Punch biopsy? Where do you use it
A
- The punch comprises a circular blade attached to a plastic handle. Diameters of two to
ten millimetres are available. - The punch removes a core of tissue the base of which can be simply and
atraumatically released using curved scissors. - The resultant wound may not require suturing if using the smaller diameter punches.
can be used on tongue/esthetic areas
21
Q
Principles of Antibiotic treatment. When do you use narrow spectrum vs broad spectrum
A
use broad initally then narrow with C/S results?
or only narrow empiric therapy
22
Q
Most definitive treatment for dental infection is….
A
removal of infection source: extraction, pulpectomy, debride non-vital bone, remove foreign body
23
Q
Please know the difference about cellulis vs abscess.
What is cellulis, including physiological level
What is Abscess…..
A
cards added
24
Q
Different types of treatment for different types of Osteomyelitis
A
surgical and medical tx
25
Odontogenic tumor (know the demographics, treatment)
AOT
Ameloblastoma (please know ameloblastoma well, this is one the crappy pathology that dentist must know well without excuse. Where do you see them, what they looks like on x-ray…….)
Odontoma
cards added
26
AOT demo/tx
* This is a tumor that is commonly found in teenagers.
* It occurs in the middle and anterior portions of the jaws
* Commonly associated with the crown of an impacted anterior tooth as unilocular RL
* Two-thirds occur in the maxilla and it is more common in females.
* The maxillary incisor-cuspids are common sites.
* Painless expansion is often the chief complaint.
* Treatment is with simple surgical enucleation and recurrence is extremely rare
27
# ameloblastoma demo/tx
cards added
28
How does Odontogenic tumor classified?
biologically and based on origin
29
Surgical Treatment types for Odontogenic tumor
eunucleation
marginal resection
partial resection
total resection
composite resection
all of these followed by reconstruction
30
Odotogenic cyst, histologically what is it and what kind of lining do they have inside/outside?
Odontogenic cyst can be defined as a cyst in which lining of lumen is derived from
epithelium produced during tooth development. (CT wall)
31
How does Odontogenic cyst classified? i.e. developmental vs….??
developmental vs inflammatory
32
# Common treatment for Odontogenic cyst
sx options
Curettage
Enucleation
Marsupialization
Marsupialization followed by cystectomy
Enucleation followed by Peripheral ostectomy
33
Please know everything about OKC (treatment, clinical appearance, x-ray appearance)
please include Carnoy Solution
Enucleation followed by use of Carnoys solution
* Enucleation followed by peripheral ostectomy and removal of overlying attached mucosa + use of Carnoys solution
* Surgical resection for very large –recurrent lesions
* variable radio app, can be scalloped , clinically can appear as enlarging mass
34
Biopsy… What is incisional vs excisional biopsy?
incisional: for large lesions, not whole lesion taken, malignancy suspected
excisional: smaller lesions, whole thing taken
35
Aspirational biopsy? How does it work and what “instrument” do you use?
use 18g needle and 5-10mL syringe to aspirate fluid from lesion guided by CT scan if deeply seated, done to rule out vascular lesions or on any lesions thought to contain fluid
36
What’s that liquid in the biopsy jar?
10% formalin to prevent autolysis
mucocutaneous lesions jar has michel's solution for IF
37
Osteomyelitis occurs in …… where? What kind of bone?
likes to occur in mandible due to dense poorly vascularized cortical plates, medullary bone infected and inflammed can spread to cortical plates/periosteum
less likely in maxilla due to better blood supply and less dense bone
38
Spread of Oro-Facial Infections
* Generally, infections follow?
* This is dictated by?
* Infective processes can spread by disruption of ?
Spread of Oro-Facial Infections
* Generally, infections follow the path of least resistance.
* This is dictated by anatomic location of teeth, position of muscle attachments, bone density, etc.
* Infective processes can spread by disruption of intervening fascial planes.
39
primary maxillary spaces for infection
* canine
* buccal
* infratemporal
40
primary man spaces for infection
* submental
* buccal
* sabman
* sublingial
41
secndary fascal spaces
* masserteric
* pterygoman
* superficial and deep temp
* lat pharyngeal
* retropharyngeal
* prevert
42
Sublingual Space Infection
above mylohyoid, commonly PM and 1st M (apices above mylohyoid line)
43
Submandibular Space Infection
below mylohyoid, 2nd/3rd molars
44
key sign of subman infection
no palpation of inf cortex
45
Submental Space Infection
also below mylohyoid, anterior teeth
46
Retropharyngeal Space Infection
can compromise airway
47
mediastinitis spread path
48
ludwigs spread path
49
# cavernous thrombosis spread path
50
danger signs of clinical exam
* trismus
* no palpation inferior border
* visual changes
* malaise/fever
* SOB
* difficulty swallowing
51
C.T. Scan with contrast use
C.T. Scan with contrast helps as follows,
-It clearly delineates the position and size of the infection process as well as its relationship with the adjacent
anatomic structures.
-It is also useful to evaluate any changes to the patient’s upper airway(due to edema) as it occurs in more advanced
infections of the head and neck.
52
CT contrast will exhibit what around infection
53
Serious Space Infections
Ludwigs Angina.
Cavernous Sinus Thrombosis
54
Cavernous Sinus Thrombosis:
* Serious condition that is recognised by the appearance of? as a result of?
* uni or bilateral?
* more or less common than ludwigs?
* Serious condition that is recognised by the appearance of marked oedema and congestion of the eyelids and conjunctiva as a result of impaired venous drainage.
* This start as a unilateral and rapidly becoming bilateral.
* This condition is not as common as Ludwig’s Angina
55
Cavernous Sinus Thrombosis - Aetiology
- Hematogenous spread of infection from the jaw to the cavernous sinus may occur anteriorly via the inferior or superior opthalmic vein or posteriorly via emissary veins from the pterygoid plexus. Direct extension through the
opening in the cranial bones.
56
Cavernous Sinus Thrombosis
Signs & Symptoms
– Ocular?
– fever?
– Periorbital and conjunctival?
– exopthalmamus/retina?
– pupils?
– Other cranial nerves?
– Ocular pain.
– High fluctuating fever, chills, and sweating.
– Periorbital and conjunctival oedema, starting unilaterally and progressing to bilateral as a result of thrombophlebitis.
– Pulsating exophthalmos and retinal haemorrhage
– Ophthalmoplegia, paralysis, dilated pupils and loss of corneal reflexes
– Other cranial nerve involvement e.g. trigeminal nerve
57
Cavernous Sinus Thrombosis - Management
– Hospital?
– consult with?
– Abx?
– Rx for thrombosis?
– Hospitalization.
– Neurosurgical consultation.
– Intensive antibiotic therapy.
– Heparin to prevent extension of thrombosis
58
Microbiology of Oral Infections
Most oral infections are mixed in origin consisting of aerobic and anaerobic gram positive and gram negative organisms
Anaerobes predominant (75%)
59
Mix of Bacteria Present in Odontogenic Infections
From Early To Late Stage
60
edema, cellulitis, abcess comparisons
61
Spread of Odontogenic Infections
Propagation of?
Spreads how?
Favors path of?
Location determined by:
most present as?
Propagation of infection
Spreads equally in all directions
Favors path of least resistance
Location determined by:
Thickness of bone at apex
Muscle attachments
Most present as a vestibular space abscess
62
Cellulitis
app? palpation?
Inflammatory response not yet forming?
Microorganisms?
Diffuse, reddened, brawny swelling that is tender to
palpation.
Inflammatory response not yet forming a true abscess.
Microorganisms have just begun to overcome host defenses and spread beyond tissue planes.
63
Abscess formation
As inflammatory response matures and?
An abscess is a?
drainage?
As inflammatory response matures and an abscess develops.
An abscess is a localized collection of pus.
May develop spontaneous drainage intraorally or extraorally
64
Osteomyelitis - Pathogenesis
in mandible
65
Osteomyelitis - Pathogenesis
Primarily a result of? allows?
Results in an? limiting?
With progression, the condition is considered?
* Primarily a result of odontogenic infections or trauma, which cause inoculation of bacteria into the jaws.
* Results in an inflammatory cascade that is usually self-limiting in the healthy patient.
* With progression, the condition is considered pathologic
66
Osteomyelitis - Pathogenesis
* Infection and associated inflammation(edema) spreads into?
* Pus travel through? accumulates where?
* Ultimately, cortical bone will? result?
* Reduced blood supply causes?
* Infection and associated inflammation (edema) spreads into marrow spaces and causes compression of blood vessels and therefore causes severe compromise of blood supply.
* Pus travel through haversian & volkaman's canal and accumulation beneath the periosteum & elevating it from cortex & there by reducing the blood supply.
* Ultimately, cortical bone perforates, compromising periosteal blood supply as well.
* Reduced blood supply causes necrosis of bone.
67
Osteomyelitis - Pathogenesis
* Small section of necrotic bone may get completely? what if larger?
* The dead bone is surrounded by the new viable bone this is called?
* Then pus penentrate the?
* fistulas?
* Small section of necrotic bone may get completely lysed while large get localized and get separated from the shell of new bone by bed of granulation tissue.
* The dead bone is surrounded by the new viable bone this is called involucrum.
* Then pus penentrate the periosteum & mucosal & cuteneous fistulae develop and thereby discharging the purulent pus.
* Intraoral or extraoral fistulas usually develop.
68
Osteomyelitis - Pathogenesis
* Bacteria then proliferates as what cannot reach site? spreads until?
* Bacteria then proliferates as normal blood-borne defenses do not reach the tissue and the osteomyelitis process spreads until it is stopped by surgery and medical treatment
69
Osteomyelitis - Microbiology
Usually a?
Osteomyelitis of the long bones usually caused by?
Usually a mixed infection when involving the jaws.
Osteomyelitis of the long bones usually caused by Staphylococcus aureus
70
Osteomyelitis - Classification
Many systems?
System developed by ? is the most practical today
This system divides osteomyelitis into what types based on?
Many systems have been developed in the past
System developed by Hudson is the most practical today
This system divides osteomyelitis into Acute and Chronic types based on presence for a 1 month duration
71
Osteomyelitis - Clinical presentation, which is highlighted?
– Pain
– Swelling and erythema of overlying tissues
– Adenopathy
– Fever
**– Paresthesia of the inferior alveolar nerve**
– Trismus
– Malaise
– Fistulas
72
Osteomyelitis - Laboratory work-up
In the acute phase, common to see?
sensitive indicators of inflammation but non-specific?
In the acute phase, common to see leukocytosis, which is uncommon in the chronic phases.
Elevated ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein) which are sensitive indicators of inflammation but non-specific.
73
Osteomyelitis - Imaging
Radiographic images lag? why?
Acute osteomyelitis often appears?
Till at least ?% destruction of mineralized portion of bone takes place – this destruction is not visible on radiograph?
Chronic osteomyelitis app?
Radiographic images lag behind the clinical presentation since cortical involvement is required for any change to be evident.
Acute osteomyelitis often appears normal radiographically
Till at least 30-60% destruction of mineralized portion of bone takes place – this destruction is not visible on radiograph.
Chronic osteomyelitis – moth eaten appearance
74
Osteomyelitis - Imaging
– what is recommended initially?
– Gives information of?
– Orthopanoramic view is recommended initially
– Easily obtainable
– Gives information of possible sources and progression.
75
Osteomyelitis - Imaging
* what have become standard?
– Provide detailed?
– Require ?% demineralization before changes are seen.
– Allow assessment of ?
* C.T scans have become standard
– Provide detailed 3 dimensional views.
– Require 30-50% demineralization before changes are seen.
– Allow assessment of the cortices
76
Osteomyelitis - MRI
* It can assist in? how?
* what are seen more accurately in MRI when compared to a CT scan?
* It can assist in early diagnosis by detection of bone marrow changes prior to cortical involvement.
* Bone marrow changes and soft tissue changes are seen more accurately in MRI when compared to a CT scan.
77
Osteomyelitis - Treatment
Both what interventions are required?
Medical therapy alone?
Tissues from the affected site should be sent for?
Immunocompromised states should be?
Both medical and surgical interventions are required.
Medical therapy alone will not suffice, and will only delay appropriate treatment.
Tissues from the affected site should be sent for microbiological exam, culture and sensitivity, and histopathological examination.
Immunocompromised states should be controlled medically to achieve optimum response to therapy
78
Osteomyelitis – Medical Treatment
* Begin abx based on?
* Best choice of antibiotic can be determined following?
* Begin empiric antibiotic treatment based on Gram stain(microbiological exam) results.
* Best choice of antibiotic can be determined following C & S results, which can take several days
79
Osteomyelitis – Medical Treatment
IV antibiotic therapy?
Treatment may include what agents?
Infectious disease consult?
HBO therapy for?
* IV antibiotic therapy for 6 weeks is routinely used
* Treatment may include carbapenems, cephalosporins, fluoroquinolones, Clindamycin, Metronidazole, or combination therapy.
* Infectious disease consult may be considered
* HBO therapy for chronic refractory osteomyelitis may be considered
80
Hyperbaric Oxygen Therapy (HBOT)
Chronic refractory osteomyelitis is?
* Hyperbaric oxygen is indicated in treatment of “Chronic Refractory osteomyelitis"
* Chronic refractory osteomyelitis is a persistent or recurrent bone infection lasting longer than six months despite appropriate surgical and medical treatment.
81
Hyperbaric Oxygen Therapy(HBOT)
* HBOT involves placing a patient
in a chamber where they
breathe ?% oxygen at ? atmospheric pressure.
* A typical course of treatment for
Chronic refractory osteomyelitis
consists of a ? minute session
for ? days per week for ? to
? treatments based on their condition
* HBOT involves placing a patient
in a chamber where they breathe 100% oxygen at increased atmospheric pressure.
* A typical course of treatment for Chronic refractory osteomyelitis consists of a 90 minute session for five days per week for 20 to 60 treatments based on their condition
82
Hyperbaric oxygen treatment – Mechanism of action
- Enhanced?
- Angiogenesis?
- Osteo?
- Synergistic?
- Enhanced leukocyte oxidative killing
- Neo-Angiogenesis
- Osteogenesis
- Synergistic antibiotic activity
83
Osteomyelitis – Surgical Treatment
Sequestrectomy
* Sequestrectomy is the removal of infected and avascular pieces of bone.
* Since the sequestrum is avascular, antibiotics will not be able to penetrate into it.
84
Osteomyelitis – Surgical Treatment Saucerization
* removal of?
* permit healing by?
* defect shape and clot?
Saucerization involves:
* the removal of the adjacent bony cortices and open packing
* permit healing by secondary intention after the infected bone has been removed.
Here the margins of the bone which lodge the sequestra are trimmed down. This create a saucer shaped
defect instead of a deep hollow cavity. This saucer shaped defect can’t accumulate a large clot
85
Osteomyelitis – Surgical Treatment: Decortication
* removal of?
* periosteum role?
* key element?
involves removal of the dense, chronically infected, and poorly
vascularized bony cortex and placement of the vascular periosteum adjacent to the medullary bone to allow increased blood flow and healing in the affected area.
* Key element is cutting back to healthy bleeding bone – clinical judgement
86
Osteomyelitis – Surgical Treatment
Additional considerations
* May support weakened mandible using?
* Segmental resection usually a?
* May support weakened mandible using external fixation, reconstruction plate, or MMF.
* Segmental resection usually a last resort following multiple attempts at more conservative debridement
87
# tx xhronic refactory osteomyelitis
HBOT
88
# tx after multiple failed conservative debridements of osteomyelitis
segemental resection
89
Common Tumors of Odontogenic Epithelium
* composed of?
* examples?
Epithelial odontogenic tumors are composed of odontogenic epithelium without participation of odontogenic ectomesenchyme.
- Ameloblastoma
- Adenomatoid Odontogenic tumor (AOT)
90
Tumors of Odontogenic Epithelium: Ameloblastoma
* B/M?
* invasive?
* spread?
* Occasionally arise from?
* Benign, but locally invasive (Except for the Malignant variant).
* It is unencapsulated and infiltrates surrounding bone marrow.
* Even though they are locally infiltrative, they do not metastasize (Except for the Malignant variant).
* Occasionally arise from dentigerous cysts
91
ameloblastoma most common locations?
92
Ameloblastoma
* Clinical Subtypes – %
* It occurs chiefly in ?
* They may occur where?
* Clinical Subtypes –
- **Multicystic or Solid (86%),**
- Unicystic (13%), and
- Peripheral (extraosseous) and Malignant variant (1%)
* It occurs chiefly in middle age people long after odontogenesis has ceased.
* They may occur in any part of both jaws but most are in the middle and posterior regions of the mandible.
93
Ameloblastoma: Radiographic findings
* They may be unilocular but frequently become multilocular as they increase in size.
* The unilocular lesion is indistinguishable from an odontogenic cyst.
* Well-circumscribed, “soap- bubble appearance” (Multicystic or Solid variant).
94
Ameloblastoma: Treatment according to?
* According to growth characteristics and type
95
Unicystic Ameloblastoma tx?
– Complete removal (Enucleation)
– Peripheral ostectomies if extension through cyst wall
96
Classic infiltrative (aggressive) – “Solid Ameloblastoma” tx
– Mandibular –
– Maxillary –
– Mandibular – adequate normal bone around margins of resection
– Maxillary – more aggressive surgery, 1.5 cm margins
97
Ameloblastic carcinoma tx
– Radical surgical resection (like SCCa)
– Neck dissection
98
cysts and tumors with nn's
cysts will diplace nn, often no symptoms, tumors will compress nn leading to neurological symptoms
99
# which imaging is used for sx planning/ is the gold standard?
CT
100
obtaining tissue for diagnosis with tumors
Obtain tissue: DONE AFTER CT SCAN DO NOT WNAT ANY INFLAMM FOR SCAN
– Aspiration – r/o vascular lesions, inflammatory, DONE FIRST
– Incisional biopsy – larger lesions prior to definitive therapy
– Excisional biopsy – smaller tumors
Establish Definitive Diagnosis !
101
Surgical Management of Odontogenic Tumors
Surgical Management includes:
* The type of surgical approach that is going to be employed is mainly dependant on?
* The type of reconstruction is mainly decided based on ?
*
* “Surgical removal” of the odontogenic tumor followed by appropriate method for reconstruction of the defect.
* The type of surgical approach that is going to be employed is mainly dependant on the type (Biologic behavior) of the tumor and it’s size.
* The type of reconstruction is mainly decided based on the size and extent of the defect (Both Hard and Soft tissue)
102
Odontogenic Tumors - Surgical Treatment Options
* Enucleation: smaller, low recurrence
* Resection: larger, aggressive lesions
- Marginal(Segmental) resection
- Partial resection
- Total resection
- Composite resection
103
Enucleation of Odontogenic Tumors
what kind of lesions?
approach?
* Local removal of tumor by appropriate instrumentation in direct contact with the lesion: used for** very benign types of lesions.**
* intra oral approach can be used to reduce scarring
104
after tumor is removed via nucleation what is done with it
sent for histo exam
105
Marginal (Segmental) resection
* Resection of a tumor without disruption of the continuity of the bone.
* minimizes tumor spillage and reduces recurrence
* 1-1.5cm surrounding tissue removed
106
Partial Resection
* Resection of a tumor by removing full-thickness portion of the jaw.
* Extra oral approach
* In the mandible, this can vary from a small continuity defect to a hemimandibulectomy.
* Jaw continuity is disrupted.
107
total resection
* Resection of a tumor by removal of the involved bone.
* Eg., Hemi-Maxillectomy and Hemi-Mandibulectomy
108
Composite Resection
* Resection of tumor with bone, adjacent soft tissues and contiguous lymph node channels (This is an ablative procedure** used most commonly malignant tumors)**
109
Rationale for Surgical Reconstruction of the Jaws
* To Restore the:
* Form of the Maxilla and mandible
– Maintain correct anatomical relation to the jaws
– Important for dental rehabilitation (endosseous implant placement)
* Function - Mastication and Speech
* Aesthetics
110
Types of Grafts Used for Reconstruction of the Jaws
free bone used with smaller defects, vacularized used with larger defects (has aa/vv attatched)
111
# AOT common sites
112
Compound and Complex Odontomas
* The tumors in which odontogenic differentiation is?
* In these tumors, the epithelium and ectomesenchyme?
* As a result, these tumors are mostly?
* commonality?
* The tumors in which odontogenic differentiation is fully expressed are the odontomas.
* In these tumors, the epithelium and ectomesenchyme realize their potential and make enamel and dentin respectively.
* As a result, these tumors are mostly radiodense.
* Odontomas are the most common type of odontogenic tumors seen in the oral surgery clinic.
113
Complex Odontoma
* In the complex odontoma, there is little or no tendency to form tooth-like structures.
* The dentin and enamel are entwined in a mass that bears no resemblance to teeth.
114
Compound Odontoma
In the compound odontoma, multiple small and malformed tooth-like structures are formed creating a “bag of marbles” radiographic appearance.
115
Complex and Compound Odontomas
* Both types of odontoma are found when?
* which types are more common where?
* Many are associated with?
* growth? pain? deformity?
* Treatment is?
* Both types of odontoma are found in the early years, usually in the teens or early twenties.
* Compound odontoma is more common in the anterior jaw segment whereas the complex type is found more commonly in the posterior jaws.
* Many are associated with an unerupted tooth.
* They have a limited growth potential and cause no pain or cosmetic deformity.
* Treatment is elective surgery.
116
Cementoblastoma
*neoplasm of?
* This tumor typically occurs where?
* Cortex?
* Involved tooth is?
* True benign neoplasm of cementoblasts, tumor of odontogenic ectomesenchyme
* This tumor typically occurs around the roots of the lower posterior teeth (First Mandibular molars)
* Cortex expanded without pain
* Involved tooth ankylosed.
117
Cementoblastoma - Radiographic examination
Radiographically it appears as a ball of dense material attached to
the end of the root.
118
Cementoblastoma - Treatment
Complete excision of the lesion along with extraction of the
involved tooth.
119
most common odontogenic cyst?
PA cyst
120
how is PA border on radio?
well defined opaque rim= slow growing
121
what cysts like to recur?
OKC
122
Classification of Odontogenic Cysts
Histogenic Classification (Based on where the cyst is derived from)
Inflammatory vs Developmental
123
Cyst derived from rest cell of Malassez
Periapical cyst
Residual cyst
124
Cyst derived from reduced enamel epithelium
Dentigerous cyst
Eruption cyst
125
Cyst derived from dental lamina (Rest of Serrae)
Odontogenic keratocyst
Dental lamina cyst of new born
Lateral periodontal
Glandular cyst
126
Unclassified cyst
Paradental cyst
127
inflammatory cysts
Radicular Cyst
Paradental Cyst
128
developmental cysts
Dentigerous Cyst
OKC
lateral periodontal Cyst
Glandular odontogenic Cyst
129
most common developmental cyst
dentigerous cyst
130
when removing a tooth with cyst what should always be done
tissue sample of cyst sent for histo exam to confirm diagnosis
131
# what needle gauge is used for aspiration
18g
132
Curettage
Curettage describes a surgical scraping of the cyst from the bony walls of the maxilla or mandible with a special instrument called a curette that has a scoop, at its tip.
For this procedure, it is important to create a bony window to expose the cyst in the maxilla or mandible.
133
Marsupialization
Marsupialization refers to creating a surgical window in the wall of cyst & evacuation of cystic contents.
This process decreases intracystic pressure & promotes shrinkage of cyst & bone fill (endosteal bone formation)
**used when close to vital strucutures **
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how do we prevent infection with marsuprialisation
acrylic plug
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what is placed in cyst, esp. OKC, to prevent recurrence
often use iodophorm gauze or canroy
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another tx options for OKC
* Enucleation followed by use of Carnoys solution
* Enucleation followed by peripheral ostectomy and removal of overlying attached mucosa + use of Carnoys solution
* Surgical resection for very large –recurrent lesions
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# follow up schedule for OKCs
* 1st year: every 6mo
* after year 1: once sa year
* after 5 yrs: every 2 years
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# Carnoy solution
substance used as a complementary treatment after the conservative excision of odontogenic keratocyst. The application of Carnoy's solution promotes a superficial chemical necrosis and is intended to reduce recurrence rates.
The application of Carnoy’s solution, a chemical solution composed of 60% ethanol, 30% chloroform, and 10% acetic acid, in conjunction with surgery, is known to reduce the rate of KOT recurrence. An FDA ban in 2013 on the use of chloroform for compounding led a number of surgeons to adopt a modified Carnoy’s solution in the use of Odontogenic Keratocyst
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Marsupialization: Indications
Anatomical considerations
Surgical access
Assistance in eruption of teeth
Extent of surgery
Size of cyst
Anatomical considerations – Proximity of cyst to vital structures like maxillary sinus, Neurovascular bundle.
Surgical access – If access to all portions of cyst is difficult.
Assistance in eruption of teeth – In a young patient with a dentigerous cyst, it permits eruption of unerupted teeth.
Extent of surgery – Marsupialization is preferred in a unhealthy or debilitated patient , because it is simple & less stressful for patient.
Size of cyst – In a very large cyst, there is a risk of fracture of jaw during enucleation procedure
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Marsupialization: Relative Contraindications
Recurrent Odontogenic Keratocyst
Recurring Cysts
Smaller Cysts (< 2X2 cm)
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Marsupialization: Advantages
Simple?
Spares?
Even quite large cyst?
eruption?
Prevents what in maxilla?
Simple procedure to perform (biggest pro)
Spares vital structures eg. blood vessels, nerves
Even quite large cyst can be dealt under Local anesthesia as anesthesia of deeper recesses is not essential.
Allows eruption of teeth (no damage to tooth)
Prevents oronasal, oroantral fistulae in the maxilla
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Marsupialization: Advantages
Reduces?
Prevents?
blood loss/ shrinkage
bone formation?
Alveolar ridge?
Reduces operating time.
Prevents intraoperative fractures.
Reduces blood loss, helps in shrinkage of cystic lining.
Allows for endosteal bone formation to take place.
Alveolar ridge is preserved.
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Marsupialization: Disadvantages
Pathologic tissue?
Histologic examination of entire cystic lining?
post op care?
tastes and smell?
pack/plug?
Secondary surgery?
healing time ?
Pathologic tissue is left in situ.
Histologic examination of entire cystic lining is not done.
The need for regular postoperative care, occurs over a substantial period of time.
Unpleasant taste and smell may occur due to accumulation of stagnant saliva & food debris in cystic cavity.
Changing of pack and adjustment of plug.
Secondary surgery may be needed.
Longer healing time.
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Enucleation
Enucleation means?
This procedure is usually indicated for removal of cyst that is?
Enucleation allows for cystic cavity to be covered by? which allows?
Enucleation means shelling out the entire cystic lesion without rupture.
This procedure is usually indicated for removal of cyst that is not very large in size and has minimum risk of injury to vital anatomical structures during the surgical procedure.
Enucleation allows for cystic cavity to be covered by a mucoperisteal flap & the space fills with blood clot, which will eventually organize & form normal bone.
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Enucleation: Indications
Treatment of?
Recurrence?
Should be employed with any cyst that can be?
Treatment of Common types of odontogenic cysts (odontogenic keratocysts, Radicular cysts, Dentigerous cyst etc.,)
** Recurrence of cystic lesions of any cyst type.**
Should be employed with any cyst of jaw that can be safely removed without unduly sacrificing the adjacent structures.
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Enucleation: Relative Contraindications
Dentigerous cyst associated with?
pt ages?
Medically compromised or debilitated patients?
Proximity?
size of cysts?
Dentigerous cyst associated with teeth other than the third molars that would erupt normally in the oral cavity and be functional.
**Young patients with erupting teeth.**
Medically compromised or debilitated patients who require extensive surgical
procedure to treat the cyst.
Proximity to vital structures.
Very large cysts, may cause fracture of jaw.
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Enucleation: Advantages
pathological tissue?
Tissue available for?
recurrence?
Healing time?
Enucleation with primary closure eliminates need for?
Entire pathological tissue is removed.
Tissue available for histopathological examination.
Chances of recurrence are less.
Healing time is reduced.
Enucleation with primary closure eliminates need for repeated appointments for packing, irrigation, adjustment of plug etc
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Enucleation: Disadvantages
In young patients?
Removal of large cyst?
Damage to?
Adjacent tooth?
In young patients, the unerupted teeth in a dentigerous cyst will have to be removed
with the lesion.
Removal of large cyst may make mandible more prone for fracture.
Damage to adjacent vital structures.
Adjacent tooth may be devitalized.
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Combination of Marsupialization and Cystectomy
Cystectomy after Marsupialization (decompression) is a conservative technique that decreases the size of the cystic cavity and reduces the risk of intrabony defects, which could be induced by primary enucleation.
In addition, it can also save the adjacent anatomic structures- As the surgery is carried out in 2 stages
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# stages of combined marsupialization and cystectomy
Stage 1 – Marsupialization
Stage 2 - Cystectomy
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Combination of Marsupialization and Cystectomy
Stage 1
In these cases, the Marsupialization(decompression) is performed usually on on huge cystic lesions of the mandible.
During this process, a decrease in the size of the lesion and the growth of normal oral tissues was observed. The size of the lesion decreased until the time of cystectomy.
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Combination of Marsupialization and Cystectomy
stage 2
Cystectomy is carried out later after the size of the cyst decreases considerably in size over a period of time and surgery could be performed under local anesthesia.
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Enucleation followed by Peripheral ostectomy
exactly what it says, prevent recurrence is main goal
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Curretage followed by Peripheral ostectomy
Peripheral ostectomy is defined as a peripheral bone. reduction with
powered hand-piece and rotary instruments, done after enucleation of the cystic lesion
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Osteomyelitis - Incidence
* which arch? why?
* Much higher in the mandible due to the dense, poorly vascularized cortical plates.
* Maxillary bone is much less dense with excellent blood supply.
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Osteomyelitis – Predisposing factors
Immuno-compromised status
and Conditions that affect the Jaw vascularity
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Osteomyelitis - Pathogenesis
in mandible
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Osteomyelitis - Pathogenesis
Primarily a result of? allows?
Results in an? limiting?
With progression, the condition is considered?
* Primarily a result of odontogenic infections or trauma, which cause inoculation of bacteria into the jaws.
* Results in an inflammatory cascade that is usually self-limiting in the healthy patient.
* With progression, the condition is considered pathologic
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Osteomyelitis - Pathogenesis
* Infection and associated inflammation(edema) spreads into?
* Pus travel through? accumulates where?
* Ultimately, cortical bone will? result?
* Reduced blood supply causes?
* Infection and associated inflammation (edema) spreads into marrow spaces and causes compression of blood vessels and therefore causes severe compromise of blood supply.
* Pus travel through haversian & volkaman's canal and accumulation beneath the periosteum & elevating it from cortex & there by reducing the blood supply.
* Ultimately, cortical bone perforates, compromising periosteal blood supply as well.
* Reduced blood supply causes necrosis of bone.
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Osteomyelitis - Pathogenesis
* Small section of necrotic bone may get completely? what if larger?
* The dead bone is surrounded by the new viable bone this is called?
* Then pus penentrate the?
* fistulas?
* Small section of necrotic bone may get completely lysed while large get localized and get separated from the shell of new bone by bed of granulation tissue.
* The dead bone is surrounded by the new viable bone this is called involucrum.
* Then pus penentrate the periosteum & mucosal & cuteneous fistulae develop and thereby discharging the purulent pus.
* Intraoral or extraoral fistulas usually develop.
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Osteomyelitis - Microbiology
Usually a?
Osteomyelitis of the long bones usually caused by?
Usually a mixed infection when involving the jaws.
Osteomyelitis of the long bones usually caused by Staphylococcus aureus
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Osteomyelitis - Imaging
* what have become standard?
– Provide detailed?
– Require ?% demineralization before changes are seen.
– Allow assessment of ?
* C.T scans have become standard
– Provide detailed 3 dimensional views.
– Require 30-50% demineralization before changes are seen.
– Allow assessment of the cortices
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Osteomyelitis - Nuclear medicine highlights areas of?
A technetium bone scan is more sensitive than? in detecting?
However, bone scans in general are sensitive for? but not?
There is a high incidence of false positive?
Nuclear medicine -Technetium 99 highlights areas of increased
bone turnover.
A technetium bone scan is more sensitive than plain film imaging
in detecting early infections and may be positive as early as three days.
However, bone scans in general are sensitive for bone turnover, but
are generally not specific for osteomyelitis. There is a high
incidence of false positive osteomyelitis nuclear medicine studies. of soft tissue infections
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Osteomyelitis - Treatment
Both what interventions are required?
Medical therapy alone?
Tissues from the affected site should be sent for?
Immunocompromised states should be?
Both medical and surgical interventions are required.
Medical therapy alone will not suffice, and will only delay appropriate treatment.
Tissues from the affected site should be sent for microbiological exam, culture and sensitivity, and histopathological examination.
Immunocompromised states should be controlled medically to achieve optimum response to therapy
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Osteomyelitis – Surgical Treatment
Sequestrectomy
* Sequestrectomy is the removal of infected and avascular pieces of bone.
* Since the sequestrum is avascular, antibiotics will not be able to penetrate into it.
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edema, cellulitis, abcess comparisons
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biopsy of vascular lesions
NEVER, use diascopy or aspiration to determine this
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Indications for Biopsy:
* Any persistent?
* Persistent?
* Lesion that interfere with?
* Bone lesions identified by?
* Any lesion that has the characteristics
* of?
* Any persistent swelling, either
visible or palpable beneath
relatively normal tissue
* Persistent hyperkeratosis changes in tissue
* Lesion that interfere with local function (ex: fibroma)
* Bone lesions identified by radiographic finding.
* Any lesion that has the characteristics
of malignancy.
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Excisional Biopsy
Definition:
Total excision of a lesion for microscopic study is called “Excisional
biopsy”.
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excisional biopsy uses:
* growth of lesion/app?
* Removal of?
* what is also excised to ensure total removal?
* Constitute?
common lesions ?
* Slow growing lesions that appear benign on clinical examination.
* Removal of the entire lesion
* A perimeter of normal tissue surround the lesion is also excised to ensure total removal
* Constitute definitive treatment
often used with firbomas/papillomas
send to lab for definitive diagnosis and keep copy for pt
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Principle of Excisional Biopsy
The entire lesion, along with 2 to 3 mm of normal appearing surrounding tissue, is excised.
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Incisional Biopsy
* Some lesions are too large to excise initially without having established diagnosis or are of such a nature that excision would be inadvisable.
* In such instances a small section is removed for examination called incisional or diagnostic biopsy.
Use: For large lesions or when there is a suspicion of malignancy
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Principles of Incisional Biopsy
* Representative areas of lesion should be incised in?
* Selected in an area that shows?
* Necrotic tissue?
* Taken from?
* deep or broad?
* Representative areas of lesion should be incised in wedge fashion.
* Selected in an area that shows complete tissue changes (the lesion extends into normal tissue at
the base and/or margin of the lesion).
* Necrotic tissue should be avoided
* Taken from the edge of the lesion to include some normal tissue
* A deep, narrow biopsy rather than a broad, shallow one
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Aspiration
* done when?
* Aspiration is the use of? in order to?
* needle gauge/syringe?
* The tip of needle may have to be?
* done when hard to access lesion surgically
* Aspiration is the use of a needle and syringe to penetrate a lesion for aspiration of its content.
* A 18-gauge needle is connected to a 5 or 10 ml syringe
* The tip of needle may have to be repeatedly repositioned to locate a fluid center
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Indication of Aspiration
* Aspiration should be carried out on all lesions thought to contain?
* soft tisses?
* Any radiolucency in the bone of the jaw should be aspirated to rule out a?
* Aspiration should be carried out on all lesions thought to contain fluid or any intra- osseous lesion before surgical exploration
* A fluctuant mass in the soft tissues should also be aspirated to determine its contents
* Any radiolucency in the bone of the jaw should be aspirated to rule out a vascular lesion that can cause life threatening hemorrhage.
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Intraosseous and Hard Tissue Biopsy
* Any intraosseous lesion like tumors, cyst, infections(osteomyelitis) diseases like fibro-osseous lesions require?
* time for processing in the histopathological lab?
* Any intraosseous lesion like tumors, cyst, infections(osteomyelitis) diseases like fibro-osseous lesions require a bone biopsy procedure.
* Bone and other hard tissues that contain calcium takes extra time for processing in the histopathological lab.
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Fine Needle Aspiration Biopsy Use:
to biopsy deep-seated lesions
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Fine Needle Aspiration Biopsy
* Technique:
* In cases where the tumor is deep seated, then you can use?
* Technique: Uses very thin needle and a syringe to take out a small amount of fluid and very small pieces of tissue from tumor/mass.
* In cases where the tumor is deep seated, then you can use C.T.Scan guided or ultrasound guided Fine Needle Aspiration.
decreasaes risk to other structures
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Fine Needle Aspiration Biopsy
* Advantages:
- Does not require?
- Biopsy results available?
* Disadvantages:
- Needle cannot?
* Advantages:
- Does not require incision on skin.
- Biopsy results available the same day
* Disadvantages:
- Needle cannot remove enough tissue for diagnosis
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Anesthesia for biopsies
* Block or local?
* The anesthetic solution should not be injected within?
* If necessary, infiltration of local anesthesia may be used locally, but the solution should be injected where?
* Block local anesthesia techniques are employed when possible
* The anesthetic solution should not be injected within the tissue to be removed, because it can cause artificial distortion of the specimen.
* If necessary, infiltration of local anesthesia may be used locally, but the solution should be injected at least 1 cm away from the lesion.
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Principles of Antibiotic selection
spectrum?
Based on?
Compatible with?
Narrow spectrum
Based on identification of causative organism and sensitivity
Compatible with patient’s drug histor
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principles Abx tx
Use what form of therapy?
Use what spectrum drug?
Use antibiotic with the lowest?
bactericidal vs bacteriostatic?
Be aware of?
Use Empiric Therapy
Use narrowest spectrum drug
Use antibiotic with the lowest toxicity
Use bactericidal antibiotic
Be aware of Cost
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Spread of Odontogenic Infections
* Odontogenic infection can spread from? to? can be?
* Odontogenic infection can spread from their original sites to remote areas in the head and neck and can on occasions be life threatening.
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Spread of odontogenic infections may involve what tissues/strucutures:
– Soft tissue/fascial spaces – More common
– Osseous structures (Osteomyelitis) – Less common
– Vital structures – Orbits, CNS, thoracic cavity, etc
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Spread of Oro-Facial Infections
* Generally, infections follow?
* This is dictated by?
* Infective processes can spread by disruption of ?
Spread of Oro-Facial Infections
* Generally, infections follow the path of least resistance.
* This is dictated by anatomic location of teeth, position of muscle attachments, bone density, etc.
* Infective processes can spread by disruption of intervening fascial planes.
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Fascial Spaces
* Potential spaces between the fascia and underlying organs/tissues.
* In a healthy state, these spaces do not exist. However, these spaces can be distended by fluid or infective process.
* Thus infective process can spread from one area to the adjoining ones by disruption of intervening fascial planes or around perforating blood vessels and nerves
