Oral surgery
Principles of ultrasonic physics (conversion of electrical to mechanical energy) include:
(a) Passage of high-frequency current through either a magnetostrictive (24,000
cps) or piezoelectric (42,000 cps) transducer to generate vibrations through a
smooth tip and a cooling water spray onto the tooth surface where calculus and
plaque are disintegrated, and; (b) passage of compressed air into a vibrating tip
(6,500 cps).
1. He showed me a photo of needle penetrating the buccinator towards IAN and
ask me to identify IAN, parotid, buccinator, ramus, masseter, superior
constrictor and lingual nerve
Temporalis
Frontalis
Zygomaticus
major
masseter
Buccinator
masseter
risorius
2.The patient lost consciousness in the dental chair how would manage? How do you
tell he is not breathing?
1
Identify the cause: Most common cause: Faint due to Vaso-vagal syncope. However
other causes such as strokes, corticosteroid insufficincly, drug reactions and interactions,
heart block, epileptic fit, hypoglycemia and Myocardial infarction should be ruled out
through the patients pre-medical history.
Management: Lay the pt. Flat, head is at or below the level of heart, loosen clothing,
monitor pulse. If recovery does not occur and bradycardia persists, then try tiny dose of
Atropine 100 microgram IV. Dose may be repeated upto 600 microgram.
A mirror next to the mouth of your patient and observe for fogging is the best and most
accurate way to tell whether he is breathing or not.
3.How would you manage patient with heart problems
Patients with murmurs are particulary important to dentists. Murmurs are suggestive of
defective heart valves that can be colonized with bacteria introduced via dental
instrumentation procedures leading to potentially fatal illness: IE (infective Endocarditis).
Hence antibiotic prophylaxis is essential(Refer to previous notes on ant. Proph).
In patients with compromised cardiovascular system (recent history of MI etc) avoid GA,
give adequate doses of LA with sedation if necessary, avoid excessive adrenaline loads.
Consider drug interactions for eg some pts may be under anti-coagulants. (Patients
with pulmonary embolism are treated with Coumadin(brand name for warfarin) to
prevent further blood clot emboli. Coumadin is also used in patients with atrial
fibrillation and artificial heart valves to reduce the risk of strokes)
4.How would you manage patient with rheumatic heart fever
Patients with a PMH(past medical History) of rheumatic heart fever are likely to have
damge to heart valves mostly mitral valve. They should receive antibiotic prophylaxis(ref
notes on ant.proph)unless valvular heart disease is ruled out by a cardiologist. Exclusion
of septic foci sould be requested in patients with a high risk of valvular damage.
5. 70 kg patient, what is the maximum dose of adrenaline.
0.2 mg per appointment.
Dilution in lidocaine= 1:50,000. (i.e. 1 mg of drug contained in 50,000 ml of solution)
6. Methaemoglobinaemia
A condition in which the iron within hemoglobin is oxidized from the ferrous (Fe2+) state
to the ferric (Fe3+) state, resulting in the inability to transport oxygen and carbon dioxide.
Clinically, this condition causes cyanosis, often posing a diagnostic dilemma.
2
This uncommon adverse reaction is associated most notably with prilocaine but may also
occur with articaine or the topical anesthetic benzocaine.
Methemoglobinemia is induced by an excess of the metabolites of these drugs and
manifests as a cyanotic appearance that does not respond to the administration of 100%
oxygen. Cyanosis becomes apparent when methemoglobin levels are low, but symptoms
of nausea, sedation, seizures and even coma may result when levels are very high.
Prilocaine, articaine and benzocaine are best avoided in patients with congenital
methemoglobinemia.
7. Complications of extraction of stand alone upper molar
Fracture of maxillary tuberosity, Oro-antral fistula, Retained fractured root in maxillary
antrum,
8. The four types of diabetics
IDDM, NIDDM, Juvenile diabetes, Gestational Diabetes
NIDDM: maturity onset diabetes mellitus, caused due to insulin resistance or inability to
respond to insulin in blood. Orla Hypoglycamics (Metformin, Biguanates)
IDDM: Mostly occurs in young individuals eg: juvenile diabetes mellitus. Insulin
injections.
Miscellaneous: Gestational diabetes, other nutritional deficiencies (marasmus,
kwashiorkor), hormonal imbalance, drug induced DM(drugs damaging beta-cells,
Environmental chemicals (streptozotocin, alloxan, pesticides)
9.Moderate to severe signs of hypoglycaemia
The following signs provide diagnostic clues to insulin shock /hypoglycemia
1. Weakness,dizziness
2. Pale moist skin
3. Normal/depressed respirations
4. headache
5. Altered level of consciousness
10. a. Needle stick injury , what will you do?
3

Immediately after the accident, let the wound bleed for a moment,cleanse
thoroughly with water or a saline solution, disinfect the wound using soap and
water followed by 70% alcohol. report the incident immediately to the department
dealing with occupational accidents.

Immediate action (injured person)
A blood sample should be taken as soon as possible after the injury. This sample should
be kept for at least one year. It can act as a baseline value in case infection takes place
and it becomes necessary to determine whether infection by one of the three viruses
occurred at work. The kept sample may only be analysed for this particular purpose.
Further blood samples to test for HBV, HCV and HIV are collected after 1, 3, 6 and 12
months.
Immediate action (dealing with the potential source)
If the source of the blood is known the patient must be asked for permission to sample
blood for a HCV and HIV test. If the patient refuses then it must be assumed the
patient is a carrier of the virus. If the origin of the blood is unknown then any blood
present on the needle can be used for a serological examination.
10.b. If the patient doesn't give any information and blood samples what will you
do?
Infectivity of Hepatitis C?
There is no effective drug prophylaxis for HCV.
If case is diagnosed at an early stage, there are some experimental treatment possibilities
The case should be followed closely for 12 months and a serological examination for
HCV should be done after 3, 6 and 9-12 months. If one of these follow up analyses finds
HCV antibodies then a comparison with the baseline blood sample taken immediately
after the accident will show whether or not this involves an occupational accident. In case
of a positive HCV test, a combination treatment of interferon and ribavirin is the
treatment of choice. A liver specialist should be consulted.
11. Landmarks for inferior alveolar nerve block.
Landmarks:
Mucobuccal fold
Anterior border of Ramus
Coronoid notch(greatest concavity at the anterior border of the ramus)
External oblique ridge
Retromolar triangle
Internal oblique ridge
Pterygomandibular space
Ptergomandibular raphe
Define the borders of pterygomandibular space
Lateral border: Medial aspect of the Ramus of the mandible
Medial border: Medial pterygoid muscle
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Superior border: the inferior head of the lateral pterygoid muscle.
Anteriorly: it is continuous with the recess formed by the lateral pterygoid and
temporalis muscles
Medially and posteriorly it is bound by the interpterygoid fascia, which is attached
superiorly to the base of the skull, and inferiorly to the medial aspect of the ramus of the
mandible above the insertion of the medial pterygoid muscle to the mandible.
Fractured 48 root in pterygomandibular space
12. Which local anesthetics we use here (in Australia..?)
13. Percentage of lignocaine.
2% (it is the concentration of lignocaine)
14. LA Maximum dose. How many cartridges equal to maximium dose?
Recommended maximum doses of local anesthetics with vasoconstrictor
Drug
Maximum
Maximum no.
dose of cartridges
Articaine
7 mg/kg(up to 500 mg)
7
5 mg/kg in children
Bupivacaine
Lidocaine
Mepivacaine
Prilocaine
2 mg/kg (up to 200 mg)
7mg/kg(up to 500 mg)
6.6 mg/kg (up to 400 mg) or 7 if plain
8mg/kg (up to 500 mg)
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13
11
8
Example calculations of maximum local anesthetic doses for a 15-kg (33-lb) child
Articaine
5 mg/kg maximum dose × 15 kg = 75 mg
4% articaine = 40 mg/mL
75 mg/(40 mg/mL) = 1.88 mL
1 cartridge = 1.8 mL
Therefore, 1 cartridge is the maximum.
Lidocaine
7 mg/kg × 15 kg = 105 mg
5
2% lidocaine = 20 mg/mL
105 mg/(20 mg/mL) = 5.25 mL
1 cartridge = 1.8 mL
Therefore, 2.9 cartridges is the maximum.
Mepivacaine
6.6 mg/kg × 15 kg = 99 mg
3% mepivacaine = 30 mg/mL
99 mg/(30 mg/mL) = 3.3 mL
1 cartridge = 1.8 mL
Therefore, 1.8 cartridges is the maximum.
Prilocaine
8 mg/kg × 15 kg = 120 mg
4% prilocaine = 40 mg/mL
120 mg/(40 mg/mL) = 3 mL
1 cartridge = 1.8 mL
Therefore, 1.67 cartridges is the maximum.
15. How does local anesthetics work?
The following sequence is the proposed mechanism of action of local anesthetics
1. Displacement of the calcium ion from the sodium channel receptor site, which
permits…
2. Binding of the LA molecule to this receptor site, which thus produces.....
3. ┤ Blockade of the sodium channel, and a
4. ↓ Decrease in Sodium conductance, which leads to..
5. ↓ Depression of the rate of electrical depolarization and a…
6. Χ Failure to achieve the threshold potential level, along with a…
7. Χ Lack of development of propogated action potential, which is called…
8. ┤ Conduction blockade
16. Reasons for failure of local anesthesia
Possible causes of failure are:
Wrong selection of local anesthetic solution
Technical mistakes
Anatomical variations with accessory innervation
Anxiety of the patient
Infection (most likely reason)
Mechanism of failure of local anesthesia in case of infection: Most LAs are weak bases
(7.5- 9.5). When a LA is injected into the tissue, the tissue fluid buffers neutralize it. The
cationic part of LA i.e. RNH is converted to the non-ionised base(RN). This RN diffuses
into nerve. However during pulpal/periapical inflammation the tissue pH is low(e.g. pus
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has pH of 5.5 to 5.6). Increased acidity limits 1) formation of non-ionised RN part→ion
entrapment→delay in LA onset→interferes with nerve block.
Management: Give LA at a site distant from the involved tooth→adequate pain control as
there is normal tissue conditions. Deposit larger volume of LA into the region.
17. Patients has diabetes what will you do. If it is not controlled will you make
extraction, what precaution you will take.
18. Patient taking oral medicine to control diabetes what will you do
19. What is warfarin. Up to which INR will you make your extraction in your
dental office?
Warfarin is an anti-coagulant. Drug of choice for bleeding disorders such as hemophilia,
coagulation defects, von Willebrand’s disease)Given orally, effects take 48hrs to be seen.
Normal theraupeutic range is an International Normalized ratio (INR) of 2-4. Simple
extractions are safe at a level within the theraupeutic range (INR=2-4). Avoid attempts to
reverse warfarin wth vitamin K unless in extremis. Use frozen plasma if needed, but
consider why the patient is anticoagulated in the first place.
20. How does surgicel and sponge (I forgot its name now, but you all
know the name) work, I said only one mechanism but they asked 2
mechanism for each of them.What are they made of?
Surgical and sponge: These are topical hemostatic agents which are one of the common
methods of intra-operative hemorrhage control
May be beneficial in: Exodontia, tissue biopsies,placement of endosseous implants, and
periodontal surgery, patients with coagulation defects.
Examples of topical hemostatic agents
Hemostatic Collagen: mechanical obstruction to bleeding, these materials affect the
coagulation process. In contact with blood, collagen causes aggregation of platelets,
which bind in large numbers to the collagen fibrils.
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21. Patient taking steroid, what will you do for a small operation , for
an extensive operation
23. After extraction how do you understand if there is an oroantral communication
(OAC).What will you do if you suspect there is an oroantral communication. How
many days later you will recall the patient?
OAC: An oro-antral communication is an abnormal connection between the oral and
antral cavities
OAF: an oro-antral fistula is an epithelialised connection.
Causes of oroantral communication:
-most commonly follows the extraction of a maxillary tooth closely related to the antral
floor (typically the first upper molar roots), which lies closes to the lowest point of the
antral floor.
-may also form as the result of an alveolar fracture running through the antral floor or
wall,
-may be due to direct trauma from a bur or chisel
-a cyst or infection from an upper tooth.
Signs after extraction:
¨ A visible defect between the mouth and antrum
¨ Bone fragments with a smooth concave upper surface (antral floor fragments) adhering
to the root of the extracted tooth
Investigations for OA communication:
 Careful examination using a mirror and good light, although bleeding may
obscure visibility reveals:
 The interior of the antrum may be visible
 Gentle suctioning of the socket often produces a hollow sound. Avoid probing or
irrigation.
 Ask patient to blow against closed nostrils, forcing air into the mouth—watch for
bubbles of saliva or blood from the socket.
 Radiographs are useful to confirm the diagnosis and to assess size of lesion,
although small lesions may not be visible.
Symptoms of a OAC:
 Salty tasting discharge or unpleasant smell
 Reflux of fluids and foods into the nose from the mouth
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 Escape of air when blowing nose
 Recurrent or chronic sinusitis on affected side
 Difficultly playing a wind instrument or smoking a cigarette
Treatment of OAC
sinus plasty by buccal mucoperiosteal flap.
If it is OAF, thorough removal of the entire pathologically changed maxillary sinus
mucosa with simultaneous OAC plasty frequently including radical surgery according to
Caldwell-Lüc.
Prevention of a OAC
Where there is a risk of creating an oro-antral communication it is prudent to warn the
patient beforehand. Surgical exodontia(transalveolar extraction) is preferable as it allows
more controlled bone removal. If a mucoperiosteal flap is raised it should designed to
allow repair of the OAC, should repair be necessary.
24. Precautions to be taken for Patient on anticoagulants.
25. What is INR?
A system, commonly called the INR, established by the World Health Organization
(WHO) and the International Committee on Thrombosis and Hemostasis for reporting the
results of blood coagulation (clotting) tests. All results are standardized using the
international sensitivity index for the particular thromboplastin reagent and instrument
combination utilized to perform the test.
For example, a person taking the anticoagulant ("blood thinner") warfarin (brand name:
Coumadin) might optimally maintain a prothrombin time (a "pro time" or PT) of 2 to 3
INR. No matter what laboratory checks the prothrombin time, the result should be the
same even if different thromboplastins and instruments are used. This international
standardization permits the patient on warfarin to travel and still obtain comparable test
results.
26. Antibiotic prophylaxis. (also 22. Prophylactic antibiotics for bacterial
endocarditis)
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SITUATION
AGENT
Standard general
prophylaxis
Inability of oral
medications
Allergy to penicillin
Amoxicillin
Allergy to penicillin
and Inability of oral
medications
ADULT
DOSE/ROUTE
2g
Oral
2g/kg
IM or IV
600mg/oral
CHILDREN
DOSE/ROUTE
50mg/kg
oral
50mg/kg
IM or IV
20mk/kg/oral
TIME GIVEN
2g/oral
50mg/kg/oral
1 hr pre-op
500mg/oral
15mg/kg/oral
1 hr pre-op
Clindamycin
or
600mg
IV
20mg/kg
IV
30 mins pre-op
Cefazolin
1g IM/IV
25mg/kg IM/IV
30 mins pre-op
Ampicillin
Clindamycin
(or)
Cephalexin
Cefadroxil
Or
Azithromycin or
Clalrithromycin
1 hr pre-op
30 mins pre-op
1 hr pre-op
PRINCIPLE: The regimen should be short (it should not be present too long pre-op because the
targeted pathogens will develop resistance), high dose, appropriate to the potential infecting
organisms (Staphylococcus, Streptococcus, Bartonella)
INDICATIONS:
 Patients with Cardiac conditions are at risk for endocarditis following dental manipulation
 Patients with a history of intravenous drug abuse
 Patients with Compromised Immunity: Patients with a compromised immune system may
not be able to tolerate a transient bacteremia following invasive dental procedures. This
category includes, but is not limited to, patients with Human immunodeficiency virus (HIV),
Severe combined immunodeficiency syndrome (SCIDS), Neutropenia, Immunosuppression ,
Sickle cell anemia , Status post splenectomy, Chronic steroid usage, Lupus erythematosus,
Diabetes, Status post organ transplantation.
 Certain syndromes (e.g., Down, Marfan) may be at risk for developing bacterial endocarditis
due to associated cardiac anomalies.
 Patients with vascular catheters. Vascular catheters, such as those required by
patients undergoing dialysis, chemotherapy, or frequent administration of blood
products, are susceptible to bacterial infections. Bacteremia following an invasive
dental procedure may lead to colonization of shunts or indwelling vascular
catheters
DENTAL PROCEDURES ASSOCIATED WITH HIGHER INCIDENCE OF BACTEREMIA
 Dental extractions
 Periodontal procedures including surgery, subgingival placement of antibiotics fibers/strips,
scaling and root planning, probing, recall maintenance
 Dental implant placement and replantation of avulsed teeth
 Endodontic instrumentation or surgery only beyond the apex
 Initial placement of orthodontic bands but not brackets
 Intraligamentary and intraosseous local anesthetic injections
 Prophylactic cleaning of teeth or implants where bleeding is anticipated
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27. Nerve supply of palate.
HARD PALATE
Name of nerve
Nasopalatine n.
Greater Palatine n.
Lesser Palatine n.
SOFT PALATE
Name of nerve
Nerve to medial pterygoid
Pharyngeal Plexus (consists
of the cranial part of cranial
nerve XI via the pharyngeal
branch of the Cranial nerve
X)
Foramen
Incisive foramen
Greater Palatine foramen
Lesser Palatine foramen
Foramen
Muscles supplied
Tensor veli palatine
Levator veli palatine,
palatoglossus,
palatopharyngeus, musculus
uvulae.
29. OAF (say you would refer to specialist)
Oroantral fistula—Patients should not blow their nose. Antimicrobials and nasal
decongestants help. If it is detected early, primary closure is possible, but others may
need flap closure by a specialist.
30. All instruments
31. Use of cryers elevator
To remove broken roots
32. CPR-where would u perform CPR (site)-in adult, in child. What is the rate?
What is the depth? What is the rate?
CPR
Site
Rate of
compressions
Depth of
Compressions
Adult CPR
At the spot next to Sternum where
the lower ribs meet
Child CPR
Bottom of the
ribcage where the
lower ribs meet
15 times @ the rate of about 3
compressions for every 2 seconds.
Finish the cycle by giving the
victim 2 breaths.
Complete 4 cycles and check
carotids pulse
5 compressions and
1 breath.
½ to 2 inches, with 2 hands
Complete 20 cycles
and check carotids
pulse.
1 inch, with 1
hand(bcos the child
Infant CPR
3 fingers on the infaqnts
chest with the top finger on
an imaginary line drawn
between the infants nipples
5 compressions and 1
breath.
Complete 20 cycles and
check carotids pulse.
½ inch, ½ hand(2 fingers)
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is fragile)
33. How do you test clinically if the patient had OAF
Investigations for OA communication:
 Careful examination using a mirror and good light, although bleeding may
obscure visibility reveals:
 The interior of the antrum may be visible
 Gentle suctioning of the socket often produces a hollow sound. Avoid probing or
irrigation.
 Ask patient to blow against closed nostrils, forcing air into the mouth—watch for
bubbles of saliva or blood from the socket.
 Radiographs are useful to confirm the diagnosis and to assess size of lesion,
although small lesions may not be visible.
Symptoms of a OAC:
 Salty tasting discharge or unpleasant smell
 Reflux of fluids and foods into the nose from the mouth
 Escape of air when blowing nose
 Recurrent or chronic sinusitis on affected side
 Difficultly playing a wind instrument or smoking a cigarette
34. Precautions for hypertensive patient (repeated)
35. Action of Adrenaline in LA
36. Diabetes,what precautions you will like to take(repeated)
38. anatomy muscles of mastication,mylohyoid ridge ,external oblique ridge palate.
antibiotics prophylaxsis.
39. surgicel and gelfoam
1.calculation of L.A for a 70kg adult. we were supposed to calculate the
number of cartridges. L.A of 2.2c.c with 1:100.000.
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Types of Diabetes(repeated)
Type I (IDDM) Insulin Dependant Diabetes Mellitus
Type II (NIDDM) Non-Insulin Dependant Diabetes Mellitus
Gestational Diabetes: During pregnancy
Juvenile Diabetes
41. Signs & symptoms of moderate to severe Hypoglycemia
42. What are the complications of extraction of a lone standing upper maxillary
molar?
43. Instruments
44. In what diseases does patient takes anticoagulant?
Hemophilia, Coagulation defects, von Willebrand’s disease
45. What is the higher limit the doctors give for INR ratio. In what ratio
you will do extraction and what precautions will you take?
46. SBE prophylaxis
47. CPR. Which is the most sensitive test for breathing.
Hold a glass slab near the mouth of patient. Moisture will accumulate if patient is
breathing
48. Anatomy- coronoid process
49. mental foramen-What passes through it and
what area does it innervates
Mental nerve passes through mental foramen. It innervates the skin of the chin and the
skin and mucous membrane of the lower lip.
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Pt is about to have a myocardial infarction during dental treatment-what are the
indications(symptoms) of this
Signs and Symptoms of a Myocardial Infarction

Chest pain described as a pressure sensation, fullness, or squeezing in the midportion of the
thorax

Radiation of chest pain into the jaw/teeth, shoulder, arm, and/or back

Associated dyspnea or shortness of breath

Associated epigastric discomfort with or without nausea and vomiting

Associated diaphoresis or sweating

Syncope or near-syncope without other cause

Impairment of cognitive function without other cause
A MI may occur at any time of the day, but most appear to be clustered around the early
hours of the morning and/or are associated with demanding physical activity.
Approximately 50% of patients have some warning symptoms (angina pectoris or an
anginal equivalent) prior to the infarct.
Impaction-indications for removal of impacted tooth
 Recurrent pericoronitis and chronic infection unsuccessfully treated with
irrigation and antibiotic therapy
 Resorption of adjacent teeth
 Unmanageable periodontal disease related to impaction (e.g., probable defect to
the follicular space on the distal aspect of 2nd molar)
 Associated pathologic odontogenic cysts and tumors that are developing outside
the confines of the tooth and is considered to be located in an anatomical area
independent of the tooth that requires additional surgery
 Tooth in the line of fracture
 Preventive or prophylactic tooth removal, when indicated, for patients with
medical or surgical conditions or treatments (e.g., organ transplants, alloplastic
implants, radiation therapy)
 Insufficient arch length - as prescribed by orthodontist prior to or during
orthodontic therapy prior to or during orthodontic therapy
 An impacted tooth that is so positioned that it will probably not erupt by the
middle of the third decade
3. List the types of biopsy-describe incisional biopsy
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Types of Biopsy

Incisional biopsy : Surgery, in which a part of the suspicious area is taken out of
the body. It is then looked at under a microscope to see if it's normal or abnormal.

Eg of incisional biopsy are Fine needle aspiration cytology, True cut needle
biopsy, Exfoliative cytology Punch Biopsy, Trephine biopsy

Excisional biopsy: The entire tumor mass is removed in-toto along with some
normal tissue surrounding it.
It was easy for me because Samy was asking me but some of the
candidates had areal tough time with the other examiner from Sydney.So
Sydney candidates whatch out you might get him again.
OS Theory
-Max amt of 2%lignocaine 1:100000 adrenaline to 70kg male, how many 2.2ml
cartridges(Repeated)
4types of diabetes(Repeated)
Methemoglobinemia(Repeated)
Complication long standing Max molar extraction(Repeated)
Sign & symptoms Hypoglycaemia (Repeated)
Viva
Medical history medications and any allergy.
Distortion in OPG (30%)
Picture of cadaver at section showing needle for final position for IAN Block, identify
structures lingual n, masseter m, parotid g, and mandible.
Bisphosphonates indications and complications
15
Transalveolar extraction
16