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Oral and Maxillofacial pathology
Biopsy
(Principles and Techniques)
A systematic approach should be developed in evaluating a patient with
an oral and maxillofacial lesions, which include the following steps:
1.A detailed history
2.Clinical examination:
 Extraoral
 Intraoral
3.Special investigations: (as appropriate)
 Radiography or other imaging techniques
 Biopsy for histopathology( including immunoflourescence,
immunohistochemistry, electron microscopy etc…)
 Specimens for microbial cultures
 Haematological or biochemical tests.
History:
1. Demographic details (age, gender, occupation and address)
2. History of the present complaint: history of the lesion
including onset, duration, time course of any changes in
signs and symptoms, consider any previous treatments and
their effectiveness and if there is any associated symptoms
as fever, nausea or anorexia.
3. Additional questions to ask if needed: pain (if present and
its character), abnormal sensation, anesthesia, dysphagia or
bad taste or smell.
4. Medical history : A medical history is important as it aids
the diagnosis of oral manifestations of systemic disease .It
ensures that medical conditions and medication which
affect dental or surgical treatment are identified. A detailed
drug history is essential
5. The basic medical conditions that warrant special care
include:
1-Bleeding tendencies.
2-Cardiorespiratory complaints
3-Anemias and allergies.
4-Immunocompromised patients
5-Drug treatment
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6-Infections including(HIV/AIDS)
7-Poorly controlled diabetes mellitus
8-Likelyhood of, or exsisting pregnancy
Clinical examination of the oral lesion:
 It should include the following when possible:
inspection, palpation, percussion and auscultation
 Examine the physical characters of the lesion
 The anatomic site of the lesion
 The size, shape, color of the lesion
 The surface texture and consistency of the lesion
 Lymph node examination (lymphadenopathy is a
common manifestation of infection but may also
signify malignancy )
Imaging:
 The most informative imaging techniques in the
head and neck are radiography, computerized
tomography (CT), magnetic resonance imaging
(MRI) and ultrasound.
 The radiographs can provide clues that will help in
determining the nature of the lesion.
Laboratory investigations:
 Oral lesions may be manifestations of systemic
diseases
 Examples of these systemic conditions :
hyperparathyroidism, paget’s disease, multiple
myeloma
 Serum calcium, serum phosphorus, alkaline
phosphatase and proteins determination can be
very useful in exclusion of certain pathological
conditions.
Biopsy:
Biopsy is the removal of a part or the whole of a lesion for
the purpose of diagnostic examination. There are several
types of biopsy:
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1.Surgical biopsy:
 Incisional biopsy
 Excisional biopsy
2.Oral cytology
3.Aspiration biopsy
Indications for biopsy:
1. Any lesion that persists for more than 2 weeks with no
apparent etiologic basis.
2. Any inflammatory lesion that does not respond to local
treatment after 10 to 14 days.
3. Persistent hyperkeratotic changes in surface tissues.
4. Any persistent tumescence, either visible or palpable
beneath relatively normal tissue.
5. Inflammatory changes of unknown cause that persist for
long periods.
6. Lesion that interfere with local function.
7. Bone lesions not specifically identified by clinical and
radiographic findings.
8. Any lesion that has the characteristics of malignancy.
Characteristics of lesions that raise the suspicion of
malignancy:
1. Erythroplasia –lesion is totally red or has a speckled red
appearance.
2. Ulceration-lesion is ulcerated or presents as an ulcer.
3. Duration-lesion has persisted for more than two weeks
4. Growth rate –lesion exhibits rapid growth.
5. Bleeding –lesion bleeds on gentle manipulation
6. Induration-lesion and surrounding is firm to the touch
7. Fixation –lesion feels attached to adjacent structures.
Incisional biopsy:
 An incisional biopsy is a biopsy that samples only a
particular portion or representative part of a lesion
 If a lesion is large or has different characteristics in
various locations more than one area may need to be
sampled .
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Indications:
 Size limitations
 Hazardous location of the lesion
 Great suspicion of malignancy
Technique:
 Representative areas are biopsied in a wedge fashion
 Margins should extend into normal tissue on the deep
surface.
 Necrotic tissue should be avoided.
 A narrow deep specimen is better than broad shallow
one.
Excisional biopsy:
An excisional biopsy implies the complete removal of the
lesion.
Indications:
 Should be employed with small lesions. Less than 1 cm.
 The lesion on clinical exam appears benign.
 When complete excision with a margin of normal
tissue is possible without mutilation.
Technique:
The entire lesion with 2 to 3 mm of normal appearing tissue
surrounding the lesion is excised if benign.
Oral cytology:
1. Developed as a diagnostic screening procedure to
monitor large tissue areas for dysplastic changes.
2. Most frequently used to screen for uterine cervix
malignancy.
3. May be helpful with monitoring post-radiation changes
, herpes, pemphigus.
4. The disadvantages of oral cytological procedure
include:
1-Not very reliable with many false positives.
2-Expertise in oral cytology is not widely available .
5.The lesion is repeatedly scraped with a moistened
tongue depressor or spatula type instrument . The cells
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obtained are smeared on a glass slide and immediately
fixed with a fixative spray or solution.
Aspiration biopsy:
Aspiration biopsy is the use of a needle and syringe to
penetrate a lesion for aspiration of it’s contents.
Indication:
 To determine the presence of fluid within a lesion
 To acertain the type of fluid with in a lesion .
 When exploration of an intraosseous lesion is
indicated
Aspiration:
 An 18 gauge needle on a 5 or 10 ml syringe is
inserted into the area under investigation after
anesthesia is obtained.
 The syringe is aspirated and the needle redirected if
necessary to find the fluid cavity.
Principles of surgery:
Anesthesia:
1. Block local anesthesia techniques are employed
when possible.
2. The anesthetic solution should not be injected within
the tissue to be removed, because it can cause
artificial distortion of the specimen.
3. When blocks are not possible, infiltration of local
anesthesia may be used locally, but the solution
should be injected at least 1 cm away from the lesion
Tissue stabilization: specimens should be stabilized
either by:
1. Digital stabilization
2. Specialized retractors/forceps
3. Retraction sutures
4. Towel clips
Hemostasis :
 Suction devices should be avoided
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 Gauze wrapped low volume suction may be used if
needed
Incision:
1. Incisions should be made with a scalpel
2. They should be converging
3. Should extend beyond the suspected depth of the
lesion
4. They should parallel important structures
5. Margins should include 2 to 3 mm of normal
appearing tissue if the lesion is thought to be benign
6. 5mm or more may be necessary with lesions that
appear malignant, vascular, pigmented, or have
diffuse borders.
7. Choose the most suspicious area.
8. Avoid ulcers, sloughs or necrotic areas
9. In large lesions, several areas may need to be
sampled
10.Include every fragment for histopathological
examination.
Handling of the tissue specimen
Direct handling of the lesion will expose it to crush injury
resulting in alteration the cellular architecture.
Fixation:
1. The specimen should be immediately placed in 10%
formalin solution, and be completely immersed.
2. Fixation is necessary to prevent autolysis and
destruction of the microscopic features of the
specimen.
3. Fixative must diffuse into the specimen completely
before processing.
Margins of the biopsy:
Margins of the tissue should be identified to orient the
pathologist. A silk suture is often adequate. Illustrations are
also very helpful and should be included.
Surgical closure:
1. Primary closure of the wound is usually possible
2. Mucosal undermining may be necessary
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3. Elliptical incision on the hard palate or attached
gingival may be left to heal by secondary intention.
Biopsy data sheet:
A biopsy data sheet should be completed and the specimen
immediately labeled. All patient’s history and descriptions
of the lesion must be accurate
Intraosseous and hard tissue biopsy:
Intraosseous lesions are most often the result of problems
associated with dentition.
Indications for intraosseous biopsy:
 Any intraosseous lesion that fails to respond to
routine treatment of the dentition
 Any intraosseous lesion that appears unrelated to the
dentition.
Clinical examination:
 Palpation of the area of the lesion with comparison
to the opposite side.
 Any radiolucent lesion should have an aspiration
biopsy performed prior to surgical exploration.
 Material obtained from the aspiration will provide
valuable information about the lesion if it is:
1. Solid
2. Fluid filled
3. Vascular
4. Without contents
Principles of surgery:
1. Mucperiosteal flaps should be designed to allow
adequate access for incisional/ excisional biopsy.
2. Incisions should be over sound bone.
3. Cortical perforation must be considered when
designing flaps .
4. Flaps should be full thickness
5. Major neurovascular structures should be avoided
6. Osseous windows should be submitted with the
specimen
7. Osseous perforations can be enlarged to gain access
8. The tissue consistency and nature of the lesion will
determine the ease of removal
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9. Incisional biopsies only require removal of a section
of tissue
10.Soft tissue overlying the lesion should be
reapproximated following thorough irrigation of the
operative site.
11.The specimen should be handled as previously
described.
When to refer for biopsy:
1. When the health of the patient requires special
management that the dentist feel unprepared to
handle
2. The size and surgical difficulty is beyond the level of
skill that the dentist feels he / she possesses
3. If the dentist is concerned about the possibility of
malignancy.
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