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Pre-extraction treatment
When evaluating a patient pre-extraction. It is critical that the dentist examine the patients
can have a variety of maladies that require treatment modification or medical
management before extraction can be performed safely. Special measures may be needed
to control bleeding, lessen the chance of infection, and prevent worsening of the patient's
preexisting disease state.
So that good pre-extraction assessment of difficulties which may be encountered or
complications which may occur is the basis of successful extraction technique. Time
spent in making a careful pre-extraction assessment is never wasted!
A history of general disease is very important, while the history is being taken, a general
impression of the patient is formed about the size of the mouth and jaws is noted.
During your pre-extraction examination must collect relevant medical information. if had
any problems with any previous tooth extractions, any bleeding problems.
The medicines and supplements that take (prescription, over-the-counter, and herbal).
Some common medications can cause complications with tooth extractions. As examples,
aspirin retards the blood clotting process (ibuprofen, ginko biloba, and ginseng can have
an effect on clotting too). Women who take oral contraceptives seem to be at greater risk
to develop "dry sockets" after a tooth extraction than those who don't. People who have
taken bisphosphonate drugs (such as Fossmax®) can be at greater risk for complications
associated with tooth extractions.
Intraoral examination teeth and mouth before a determination can be made that a tooth
extraction is warranted. The general cleanliness of the patient's mouth and efficiency of
his oral hygiene are then observed. Wherever necessary and whenever possible, a careful
pre-extraction scaling should be performed especially in neglected mouths, at least one
week prior to surgery being undertaken. Calculus, stagnation, and chronic inflammation
usually occur together, because local healing processes may be delayed unless the mouth
is thoroughly cleaned prior to removal of teeth. It is also possible for the patient to inhale
fragments of tartar or other infected material during the extraction, especially when the
surgery is performed under general anaesthesia in the dental chair. Such mishap may
cause a pulmonary infection.
Clinical examination of the tooth to be extracted and its supporting structures always
valuable information. The tooth may be heavily restored or grossly carious, inclined or
rotated, firm or mobile, the amount and site of sound tooth substance remaining should be
carefully noted. The supporting structures may be either infected, inflamed or
hypertrophied.
As a part of this examination they will need to take an pre-extraction radiography of the
tooth. It is not usually practicable to take a pre-extraction radiograph before every
extraction, the indication for pre-extraction X-ray as following:
1. A history of difficult or attempted extractions.
2. A tooth which is abnormally resistant to forceps extraction.
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3. If the tooth has been decided to remove by dissection.
4. Any teeth or roots in close relationship to either maxillary antrum or the inferior
alveolar nerve or mental nerve.
5. All mandibular 3rd molar, instanding premolars or misplaced canine. The root pattern
of such teeth is often abnormal.
6. Heavily restored or pulpless teeth.
7. Any tooth affected by periodontal disease accompanied by some sclerosis of the
supporting bone (hypercementosed root).
8. Any tooth subjected to trauma lead to fracture of the root and/or alveolar bone.
9. An isolated maxillary molar by the presence of a large maxillary antrum. This may
predispose to either an oro-antral communication (fistula) or fracture of the maxillary
tuberosity.
10.Any partially erupted or unerupted tooth or retained root.
11.Any tooth whose abnormal crown or delayed eruption might indicate the possibility of
dilacerations, germination, or dilated odontome.
12.Any condition which predisposes to dental or alveolar abnormality such as osteitis
deformans, Cleido-cranial dysostosis, and osteoptrosis.
13.Any patient received therapeutic irradiation to the jaws which lead to
osteoradionecrosis.
The information that obtains from their clinical examination and the x-ray will help them
formulate a diagnosis as to why the tooth should, or should not, be extracted. If a
determination is made that an extraction is indicated, depending on the anticipated
difficulty of the procedure.
If during the examination a significant level of active infection is found to be present
(primarily evidenced by the presence of swelling) may decide that need to take an
antibiotic for several days before the tooth extraction procedure is performed. Doing so
will make it less likely that complications, either during the extraction procedure or the
subsequent healing process, will occur.
Any antibiotics that are prescribed should always be taken as directed. Failure to do so
can lead to the development of bacterial resistance to the antibiotic. If have any problems
associated with taking antibiotics (including the development of a generalized rash or
itching) should report immediately.
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Other reasons why it might be necessary to take antibiotics before a tooth extraction.
Tooth extractions (as well as many other types of dental procedures) can place some
dental patients that have certain medical conditions at risk for developing a bacterial
infection subsequent to having received dental treatment. In these cases it is mandatory
that the dental patient take antibiotics before the dental procedure is performed so to
reduce the risk of this event occurring. Some of the types of medical situations that may
require that a dental patient take "prophylactic" antibiotics.
Principles of prophylactic antibiotic use are:
 Rick of infection must be significant.
 Correct narrow spectrum antibiotic must be chosen.
 Antibiotic level must be high.
 Antibiotic must be in the target tissue before extraction.
 Use the shortest effective antibiotic exposure.
Metastatic infection: is an infection that occurs at a location physically separate from the
portal of entry of the bacteria. The classic and most widely understood example is
bacterial endocarditis, which may arise from bacteria are introduced into the circulation
as a result of tooth extraction. The incidence of metastatic infection can be reduced if
antibiotic administration is used to eliminate the bacteria before they can establish an
infection at the remote site.
Factors necessary for metastatic infection:
 Distant susceptible site.
 Haemotogenous bacterial seeding.
 Impaired local defenses.
 Some impairment of the local host defenses.
Prophylaxis against infectious endocarditis
The rational for antibiotic prophylaxis of infectious endocarditis after extraction has been
based on that bacteremia has been shown to cause infectious endocarditis; viridans-group
streptococci are part of normal oral flora and have been commonly found in infectious
endocarditis; extraction can cause bacteremia because of streptococcus viridans which is
generally susceptible to the antibiotic recommended for prophylaxis of infectious
endocarditis, when the morbidity and mortality of infectious endocarditis are high the
patient must treated in the hospital with high doses of (IV) antibiotics for prolonged
periods. Although initial recovery from bacterial endocarditis approaches 100%,
recurrent episodes reduce the 5-year survival rate of patients with this disease to
approximately 60%.
The American Heart Association and American Dental Association in May 2007 put new
guidelines indicate prophylaxis only for the patients at highest risk of endocarditis
including:
o Prosthetic cardiac valve.
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o Previous infectious endocarditis.
o Congenital heart disease
 Unrepaired cyanotic congenital heart disease, including palliative shunt.
 Completely repaired congenital heart defect with prosthetic material or device
during the 1st 6 months after procedure.
 Repaired congenital heart disease with residual defects at the site or adjacent to
the site of a prosthetic patch or device.
o Cardiac transplantation recipient who have cardiac valculopathy.
Bacterial endocarditis is achieved for most routine conditions with administration of 2g
of amoxicillin orally 30-60 min before the procedure. Amoxicillin is the drug of choice
because it is absorbed from the gastrointestinal tract and provides higher and more
sustained plasma levels, and it is an effective killer of viridans-group streptococci.
For patients who are allergic to penicillin use either clindomycin, with a dose 600 mg orally 1
hour before the extraction, or cephalosporin (cephalexin) for mild allergy to penicillin and not
of an anaphylactic type. Although erythromycin is not longer recommended, the newer
antibiotic as azithromycin or clarithromycin are acceptable alterative drugs. For the pediatric
patient, the dose of the drugs that are given must be reduced.
Agent
Regimen (30-60) min before procedure
Situation
Adults
Children
Oral
Amoxicillin
2g
50 mg/kg
Parenteral
Ampicillin
2g IM or IV
50 mg/kg IM or IV
Cefazolin/ceftriaxone
1 g IM or IV
50 mg/kg IM or IV
PCN allergy, oral
Cephalexin
2g
50 mg/kg
Clindamycin
600 mg
20 mg/kg
Azithromcin/clarithromycin 500 mg
15 mg/kg
PCN allergy, ParenteralCefazolin/ceftriaxone
1 g IM or IV
50 mg/kg IM or Iv
Clindamycin
600 mg IM or IV20 mg/kg IM or IV
Some patients at risk for bacterial endocarditis may be taking daily doses of penicillin to
prevent recurrence of rheumatic fever or may already be taking an antibiotic for other reasons.
In these patients, the streptococci may be relatively resistant to penicillin. The recommendation
for this situation must be use Clindamycin, azithromycin or clarithromycin for endocarditis
prophylaxis. The cephalosporins should be avoided because of possible cross-resistance with
penicillins.
If a particular patient requires a series of dental treatments that requires antibiotic prophylaxis, a
period of 10 or more days between appointments is appropriate due to the administration of
antibiotic for several days or more continuously may promote colonization of the patient by
bacteria that are resistant to the antibiotic being given, thus making prophylaxis more likely to
fail. The 10-or-more day antibiotic free period may allow antibiotic-sensitive organisms to
repopulate the oral flora. The baseline antibiotic resistance levels are not reestablished for
several months after a course of antibiotic. For this reason, the number of dental visits should
also be minimized, consistent with the patient's tolerance level.
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If the patient do not tell abut his endocarditis before the beginning of extraction, so appropriate
antibiotic prophylaxis should be administered as soon as possible but definitely within 2 hours
after the extraction to be benefit.
Patient at risk for infectious endocarditis have a comprehensive prophylaxis program that
includes excellent oral hygiene with excellent periodic professional care by rinsed the mouth
pre-extraction with an antibacterial agent, such as cholehexidine to reduce the magnitude of
bacteremias.
Other cardiovascular conditions need prophylactic antibiotic for the preventive of metastatic
infection such as:
 Coronary artery bypass grafting may consultation with the patient's cardiologist to confirm
the management.
 Patients with a transvenous pacemaker have a battery pack implanted in their chest with a
thin wire that run through the superior vena cava into the right side of the heart may
consultation with the patient's cardiologist to confirm the management.
 Coronary artery angioplasty with or without stent placement may consultation with the
patient's cardiologist to confirm the management.
 Patient receiving renal dialysis frequently have an arteriovenous shunt surgically
constructed in their forearms to provide the team ready access to the bloodstream, may
consultation with the patient's nephrologist or renal dialysis team to confirm the management.
 Patients who have hydrocephaly may have decompression with ventriculoatrial shunt
which induce valvular dysfunction, antibiotic prophylaxis may required, may consultation
with the patient's neurosurgeon to confirm the management.
 Patient who have had severe atherosclerotic vascular disease and have had alloplastic
vascular grafts placed to replace portions of their arteries need prophylactic antibiotic if
drainage of abscesses.
Prophylaxis against total joint replacement infection
Patients who have undergone total replacement of a joint with a prosthetic joint may be at risk
for haematogenous spread of bacteria and subsequent infections. These late prosthetic joint
infection result in sever morbidity because the implant is usually lost when infections occur.
There has been great concern that the bacteremia caused by tooth extraction may result in such
infections.
In July of 2003 the American Dental Association and American of Orthopaedic surgeons
recognize that the guidelines identify the high-risk patients who are potentially susceptible to
joint infections such as:
 Prosthetic joint placed within 2 years.
 Rheumatoid arthritis.
 Systemic lupus erythematosus.
 Insulin-dependent diabetes.
 Previous prosthetic joint infection.
 Congenital or acquired immunosuppressive diseases.
 Malnourishment.
 Haemophilia.
Cardiovascular problem
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Angina pectoris: Obstruction of the arterial supply to the myocardium is one of the most
common health problems dentist encounter. The condition occurs primarily in men over age 40
and in postmenopausal women.
Angina is a symptom of ischemic heart disease produced when myocardial blood supply can
not be sufficiently increased to meet the increased oxygen requirements that results from
coronary artery disease.
The patient with a history of angina mast be take a careful history which include the frequency,
duration, and severity of angina; and the response to medications.
Management of patient with history of angina pectoris as follow:
1. Consult patient's physician.
2. Use an anxiety-reduction protocol.
3. Have nitroglycerin tablet or spray readily available.
4. Administer supplemental oxygen.
5. Ensure profound local anaesthesia before extraction.
6. Consider use nitrous oxide sedation.
7. Monitor vital signs closely.
8. Consider possible limitation of amount of epinephrine used about 0.o4 mg maximum.
9. Maintain verbal contact with patient throughout extraction to monitor status.
Myocardial infarction: MI occurs when ischemia cause cellular dysfunction and death.
Management of patient with history of MI as follow:
1. Consult patient's physician.
2. Check with physician if invasive dental care needed before 6 months since MI.
3. Check whether patient is using anticoagulants including aspirin.
4. Use an anxiety-reduction protocol.
5. Have nitroglycerin tablet or spray readily available.
6. Administer supplemental oxygen.
7. Ensure profound local anaesthesia before extraction.
8. Consider use nitrous oxide sedation.
9. Monitor vital signs closely.
10.Consider possible limitation of amount of epinephrine used about 0.o4 mg maximum.
11.Maintain verbal contact with patient throughout extraction to monitor status.
Congestive heart failure: It occurs when a diseased myocardium is unable to deliver the cardiac
output demanded by the body or when excessive demands are on a normal myocardium.
Management of patient with history of Congestive heart failure as follow:
1. Defer treatment until heart function has been medically improved and physician believes
extraction is possible.
2. Use an anxiety-reduction protocol.
3. Administer supplemental oxygen.
4. Avoid supine position.
5. Consider referral to an oral and maxillofacial surgeon.
Pulmonary problems
Asthma: when a patient relates a history of asthma, the dentist should 1 st determine through
further questioning whether the patient truly has asthma or has a respiratory problem such as
allergic rhinitis. Patient with asthma should be asked abut precipitating factors, frequency, and
severity of attacks, medication used, and response to medications.
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Management of asthmatic patient:
1. Defer dental treatment until asthma is well controlled and patient has no signs of a
respiratory tract infection.
2. Listen to chest with stethoscope to detect wheezing before major oral surgical procedures
or sedation.
3. Use an anxiety-reduction protocol, including nitrous oxide, but avoid use of respiratory
depressants.
4. Consult patient's physician.
5. if patient is or has been chronically taking corticosteroids, provide prophylaxis for
adrenal insufficiency.
6. keep a bronchodilator containing inhaler accessible.
7. Avoid used of nonsteroidal anti-inflammatory drugs in susceptible patients.
Chronic obstructive pulmonary disease: It is usually caused by long term exposure to
pulmonary irritants, such as tobacco smoke.
Management of patient with Chronic obstructive pulmonary disease:
1. Defer treatment until lung function has improved and treatment is possible.
2. Listen to chest bilaterally with stethoscope to determine adequacy of breath sounds.
3. Use an anxiety-reduction protocol, including nitrous oxide, but avoid use of respiratory
depressants.
4. Consult patient's physician before administrating oxygen.
5. if patient is or has been chronically taking corticosteroids, provide prophylaxis for
adrenal insufficiency.
6. Avoid supine position.
7. keep a bronchodilator containing inhaler accessible.
8. Closely monitor respiratory and heart rates.
9. Schedule afternoon appointments to allow for clearing of secretion.
Renal problems
Renal failure: patient in renal failure require periodic renal dialysis. These patient need special
consideration during oral surgical care. Chronic dialysis treatment typically requires the
presence of an arteriovenous shunt, which allows easy vascular access and heparin
administration, allowing blood to move through the dialysis equipment without clotting.
Elective oral surgery is best undertaken the day after a dialysis treatment has been performed.
This allows the heparin used during dialysis to disappear and the patient to be in the best
physiologic status with respect to intravascular volume and metabolic by-products.
Management of patient with renal failure and receiving haemodialysis:
1. Avoid the use of drugs that depend on renal metabolism or excretion. Modify the dose if
such drugs are necessary.
2. Avoid use of nephrotoxic drugs, such as nonsteroidal anti-inflammatory drugs.
3. Defer dental care until day after dialysis has been given.
4. Consult patient's physician concerning prophylactic antibiotic.
5. Monitor blood pressure and heart rate.
6. Look for signs of secondary hyperparathyroidism.
7. Consider hepatitis B screening before extraction. Take hepatitis precautions if unable to
screen for hepatitis.
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Renal and other organs transplant: The patient requiring surgery after transplantation is usually
receiving a variety of drugs to preserve the function of the transplant tissue such as
corticosteroids and may need supplemental corticosteroids in the perioperative period,
immunosuppressive drug as cyclosporine A after organ transplantation, may cause gingival
hyperplasia. The dentist performing oral surgery should recognize this so as not wrongly
attribute to hygiene problems.
Management of patient with renal transplant:
1. defer treatment until primary care physician or transplant surgeon clears patient for
dental care.
2. Avoid use of nephrotoxic drugs.
3. Consider use of supplemental corticosteroids.
4. Monitor blood pressure.
5. Consider hepatitis B screening before extraction. Take hepatitis precautions if unable to
screen for hepatitis.
6. watch for presence of cyclosporine A.
7. consider prophylactic use of antibiotic, particularly for patients taking
immunosuppressive agents.
Hypertension:
Chronically elevated blood pressure for which the cause is unknown is called essential
hypertension. Mild or moderate hypertension (systolic pressure of less than 200 mm Hg or
diastolic pressure of less than 110 mm Hg) is usually not a problem in oral surgical care.
Management of hypertension patient
Mild to moderate hypertension:
1. Recommend that the patient seek the primary care physicians' guidance for medial
therapy of hypertension.
2. Monitor blood pressure at each visit.
3. Use an anxiety-reduction protocol.
4. Avoid use local anaesthesia with adrenaline vasoconstrictor agent but use plane
anaesthesia or with fleprisin vasoconstrictor agent.
5. Avoid rapid posture changes in patients taking drugs that cause vasodilation.
Sever hypertension:
1. Defer elective dental treatment until hypertension is better controlled.
2. Consider referral to an oral and maxillofacial surgeon for emergency problems.
Hepatic disorders
The patient with sever liver damage requires special consideration before oral surgery is
performed. An alteration of dose or avoidance of drugs that require hepatic metabolism may
necessary. The production of vitamin K-dependent coagulation factors (II, VII, IX, X) may
depressed in sever liver diseases. Portal hypertension caused by liver disease may also cause
hypersplenism, a sequestering of platelets causing thrombocytopenia and causing prolonged
bleeding time. Patients with sever liver dysfunction may require hospitalization for dental
surgery because their decreased ability to metabolize the nitrogen in swallowed blood may
cause encephalopathy.
Management of patient with hepatic insufficiency:
1. Attempt to learn the cause of liver problem; if the cause is hepatitis B, take usual
precautions.
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2. Avoid drugs requiring hepatic metabolism or excretion; if their use is necessary, modify
the dose.
3. Screen patients for bleeding time with platelet count, prothrombin time, partial
thromboplastint time.
4. Attempt to avoid situations in which the patient might swallow large amounts of blood.
Endocrine disorders
Diabetes mellitus: It is caused by an underproduction of insulin, a resistance of insulin
receptors in end-organs to the effect of insulin or both. Diabetes is commonly divided into
insulin-dependent or non-insulin-dependent diabetes. Insulin-dependent diabetes usually begins
during childhood or adolescence. The major problem is an underproduction of insulin, which
results in the inability of the patient to use glucose properly. The serum glucose level rises
above the normal level which lead to glucosuria, polyuria, and polydepipsia.
Patients with non-insulin-dependent diabetes usually produce insulin but in insufficient
amounts because of decreased insulin activity. Insulin receptor resistance, or both. This type
begins in adulthood, is exacerbated by obesity.
Management of patient with diabetes
Insulin-dependent diabetes:
1. Defer surgery until diabetes is well controlled; consult physician.
2. Schedule an early morning appointment; avoid lengthy appointment.
3. Use an anxiety-reduction protocol, but avoid deep sedation technique in outpatients.
4. Monitor pulse, respiration, and blood pressure before, during, and after surgery.
5. Maintain verbal contact with patient during surgery.
6. Advise patients not to resume normal insulin doses until they are able to return to usual
level of caloric intake and activity.
7. Consult physician if any questions concerning modification of the insulin regimen arise.
8. Watch for signs of hypoglycemia.
9. treat infections aggressively, and give antibiotic post extraction.
Non-insulin-dependent diabetes
1. Defer surgery until diabetes is well controlled; consult physician.
2. Schedule an early morning appointment; avoid lengthy appointment.
3. Use an anxiety-reduction protocol, but avoid deep sedation technique in outpatients.
4. Monitor pulse, respiration, and blood pressure before, during, and after surgery.
5. Maintain verbal contact with patient during surgery.
6. Consult physician if any questions concerning modification of the insulin regimen arise.
7. Watch for signs of hypoglycemia.
8. treat infections aggressively, and give antibiotic post extraction.
Adrenal insufficiency: Diseases of the adrenal cortex may cause adrenal insufficiency. The
most common cause is chronic therapeutic corticosteroid drugs.
Management of patient with adrenal insufficiency:
1. Use an anxiety-reduction protocol.
2. Monitor pulse, respiration, and blood pressure before, during, and after surgery.
3. Instruct patient to double usual daily dose on the day before, day of, and day after
surgery.
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Haematologic problems
Hereditary coagulopathies: patients with inherited bleeding disorders are usually aware of their
problem, allowing the clinician to take the necessary precautions before any surgical procedure.
However, in many patients, prolonged bleeding after the extraction of the tooth may be the 1st
evidence that a bleeding disorder exists. Therefore, all patients should be questioned concerning
coagulation after previous injuries and surgery. A history of epistaxis, easy bruising, hematuria,
heavy menstrual bleeding, and spontaneous bleeding should alert the dentist to possible need
for a presurgical laboratory coagulation screening. A PT is used to test the extrinsic pathway
factors (II, V, VII, and X)m whereas a partial thromboplastin time is used to detect intrinsic
pathway factors.
Platelet inadequacy and count usually cause easy bruising and is evaluated by a bleeding time.
The management of patients with coagulopathies who require oral surgery depends on the
nature of the bleeding disorder. Specific factor deficiencies such as hemophilia A, B, or C
or von Willebrand's disease are usually managed by the perioperative administration of
factor replacement and by the use of an antifibrinolytic agent such as aminocaproic acid
(Amicar). The physician decides the form in which factor replacement is given, based on
the degree of factor deficiency and on the patient's history of factor replacement. Patients
who receive factor replacement sometimes contract hepatitis or human
immunodeficiency virus. Therefore, appropriate staff protection measures should be
taken during surgery.
Platelet problems may be quantitative or qualitative. Quantitative platelet deficiency may
be a cyclic problem, and the hematologist can help determine the proper timing of
elective surgery. Patients with a chronically low platelet count can be given platelet
transfusions. Counts must usually dip below 50,000/mm 1 before abnormal postoperative
bleeding occurs. If the platelet count is between 20.000/mm 1 and 50,000/mm1, the
hematologist may wish to withhold platelet transfusion until postoperative bleeding
becomes a problem. However, platelet transfusions may be given to patients with counts
higher than 50,000/mm3 if a qualitative platelet problem exists. Platelet counts under
20,000/mm3 usually require pre-surgical platelet transfusion or a delay in surgery until
platelet numbers rise. Local anesthesia should be given by local infiltration rather than by
field blocks to lessen the likelihood of damaging larger blood vessels, which can lead to
prolonged post injection bleeding and hematoma formation. Consideration should be
given to the use of topical coagulation-promoting substances in oral wounds, and the
patient should be carefully instructed in ways to avoid dislodging blood clots once they
have formed.
Management of Patient with a Coagulopathy
1. Defer surgery until a hematologist is consulted about the patient's management.
2. Obtain baseline coagulation tests as indicated (prothrombin time, partial
thromboplastin time, bleeding time, platelet count) and a hepatitis screen.
3. Schedule the patient in a manner that allows surgery soon after any coagulationcorrecting measures have been taken (after platelet transfusion, factor replacement,
or aminocaproic acid administration).
4. Augment clotting during surgery with the use of topical coagulation-promoting
substances, sutures, and well-placed pressure packs.
5. Monitor the wound for 2 hours to ensure that a good initial clot forms.
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6.
Instruct the patient in ways to prevent dislodgment of the clot and in whet to do
should bleeding restart.
7. Avoid prescribing nonsteriodal antiinflammatory drugs.
8. Take hepatitis precautions during surgery.
Radiotherapy problems
If the decision has been made to extract tooth before radiotherapy, the principles of
atraumatic exodontia apply. However, the concepts of bone preservation are disregarded,
and an attempt is made to remove a good portion of the alveolar process along with the
teeth and achieve a primary soft tissue closure. With the onset of radiotherapy, the normal
remodeling process is inhibited; if any sharp areas of bone exist, ulceration occurs with
bone exposure. Atraumatic handling of the mucoperiosteal flaps is necessary to ensure a
rapid soft tissue healing. Burs or files should be used to smooth the bony edges under
copious irrigation because the remodeling capability of the tissues is greatly decreased
after radiotherapy. Prophylactic antibiotic are indicated under these circumstance.
The time allowed after extraction before beginning radiotherapy traditionally, 7-14 days
or delayed for 3 weeks.
Patients who have radiotherapy, as part of their management of head and neck cancer are
at risk of developing jaw osteoradionecrosis (ORN) following dental extractions. Teeth
should be kept wherever possible as chewing function has an important bearing on the
quality of life. The presence of teeth and their later extraction places the patient at risk of
developing one of the most severe complications of radiotherapy, that of ORN.
Traditionally ORN has been defined as the exposed irradiated bone that fails to heal over
a period of 3 months. It is a chronic condition, it is not the same as a dry socket, and the
risk of developing it does not diminish with time. The accepted cause is a progressive
endarteritis with a decrease in the microcirculation. The periosteum undergoes fibrosis,
osteoblasts and osteocytes are destroyed and the marrow spaces in the bone become filled
with fibrous tissue. The major risk factors for ORN are extractions or biopsies that overly
bone. Although ORN can occur spontaneously, these procedures place the patient in great
danger.
Predisposing factors for ORN include:
1. anatomic location of the tumour.
2. total radiation dose.
3. mode of radiation delivery.
4. dental status.
Superimposed on the rate of developing ORN, extractions have been implicated more
often than any other factor. ORN is more likely to arise after the removal of mandibular
molars located directly in the treatment field. The importance of dental extractions is
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given additional significance because mandibular resection is more frequently required if
ORN occurs following extractions.
Recommendations have been made in surgical practice in an attempt to reduce the risk of
developing ORN. These can be broadly classified into preventative oral care, adjuvant
therapies such as use of hyperbaric oxygen before and after tooth extraction, modified
surgical techniques and a combination of pre- and post-operative antimicrobial protocols.
HBO therapy is the administration of oxygen under pressure to the patient. HBO has
been shown to increase the local tissue oxygenation and vascular ingrowth into the
hypoxic tissues. The usual protocol fro such treatments is to have between 20 and 30
HBO dives before extraction and 10 more dives immediately. The patient usually
undergoes one HBO session each day. Therefore, it takes 4-6 weeks to get 20-30
treatments before surgery, and 2 weeks of treatment after surgery.
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