• A specific year's paper (e.g., "February 2025")
• A specific topic (e.g., "all questions about TMJ Ankylosis across all papers")
• A list of specific questions (e.g., "Q1 from August 2024 and Q3 from February 2025")

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August 2016

February 2017

August 2017

February 2018

August 2018

February 2019

August 2019

February 2020

November 2020

September 2021

December 2021

May 2022

October 2022

February 2023

July 2023

October 2023

February 2024

August 2024

February 2025

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AUGUST 2016 - BDS Final Year Paper VII: Oral and Maxillofacial Surgery

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PART I - LONG ESSAYS (10 marks each)

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Q1. Define Cyst. Classify Odontogenic Cysts of Jaws. Write in detail the Clinical Features, Radiographic Features and Management of Odontogenic Keratocyst.

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DEFINITION OF CYST

• Toller (1966): "A cyst is a pathological cavity having fluid, semi-fluid, or gaseous contents and which is not created by accumulation of pus, frequently but not always lined by epithelium."
• Cysts of the jaws are unique because the jaw bones contain epithelial remnants from tooth development, making them particularly prone to cyst formation.

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CLASSIFICATION OF ODONTOGENIC CYSTS OF THE JAWS

A. Developmental Odontogenic Cysts

1. Gingival cyst of the newborn (Epstein's pearls / Bohn's nodules)
2. Gingival cyst of the adult
3. Dentigerous cyst (Follicular cyst)
4. Eruption cyst
5. Odontogenic Keratocyst (OKC) - now termed Keratocystic Odontogenic Tumor (KCOT) by WHO 2005
6. Lateral periodontal cyst
7. Calcifying Odontogenic Cyst (Gorlin's cyst)
8. Botryoid odontogenic cyst
9. Glandular odontogenic cyst (Sialo-odontogenic cyst)

B. Inflammatory Odontogenic Cysts

1. Radicular cyst (Periapical cyst / Apical periodontal cyst)
   • Apical
   • Lateral (lateral radicular cyst)
   • Residual cyst
2. Paradental cyst (Inflammatory collateral cyst)
   • Mandibular infected buccal cyst

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ODONTOGENIC KERATOCYST (OKC)

• WHO (2005) reclassified it as Keratocystic Odontogenic Tumor (KCOT) due to its aggressive behavior and neoplastic potential.
• WHO (2017) reverted it back to OKC classification.

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CLINICAL FEATURES

• Most common in the 2nd and 3rd decades of life
• Male predilection (M:F = 1.5:1)

• Most common in the posterior mandible (body and ramus region) - approximately 70%
• Maxilla - 30% (posterior > anterior)
• In the mandible: angle and ramus is the most common site

• Often asymptomatic - discovered incidentally on routine radiography
• When symptoms present: painless swelling, expansion of the jaw
• Can cause tooth displacement and root resorption (less common than other cysts)
• Buccal or lingual cortical perforation may occur
• Buccal expansion is less common (unlike dentigerous or radicular cysts) because the cyst tends to grow anteroposteriorly along the medullary cavity
• Aspiration yields straw-colored fluid with keratin flakes - characteristic "cheesy/milky" material with high protein content
• Multiple OKCs - strongly suggestive of Gorlin-Goltz syndrome (Nevoid Basal Cell Carcinoma Syndrome)

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RADIOGRAPHIC FEATURES

1. Shape: Well-defined unilocular or multilocular radiolucency
2. Border: Scalloped or festooned margins with a corticated (sclerotic) rim
3. Size: Can be large; tends to grow in an anteroposterior direction along the medullary cavity
4. Loculation:
   • Unilocular - more common in anterior mandible
   • Multilocular - more common in posterior mandible/ramus ("soap bubble" appearance)
5. Tooth involvement:
   • Associated with unerupted/impacted teeth (resembles dentigerous cyst)
   • Tooth displacement is common
   • Root resorption is uncommon (unlike ameloblastoma)
6. Cortical expansion: Minimal to moderate (less expansion than ameloblastoma)
7. Location relative to teeth: Can be at apex, lateral to root, or around the crown of an unerupted tooth

• Defines extent of cyst, cortical perforation, and proximity to vital structures
• Fluid appears hypodense; thickened walls may suggest inflammation/infection

• Useful in delineating soft tissue extension; cyst contents show characteristic signal intensity

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HISTOPATHOLOGICAL FEATURES

1. Epithelial lining: Thin, uniform, 6-8 cell layers thick
2. Surface: Corrugated/wavy parakeratinized surface (most common type)
   • Orthokeratotic variant is less aggressive, lower recurrence
3. Basal cell layer: Prominent, palisaded, hyperchromatic nuclei - "picket fence" or "tombstone" appearance - pathognomonic
4. Interface: Flat (no rete ridges)
5. Connective tissue wall: Thin, fibrous, uninflamed; may show daughter cysts/satellite cysts and epithelial islands
6. Budding of basal cells into the connective tissue
7. Mitotic activity present - explains recurrence potential

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MANAGEMENT OF OKC

Methods Available:

• Surgical removal of the entire cyst lining
• Curettage of the bony walls
• Recurrence rate: 25-60% (due to thin, friable lining; satellite cysts; epithelial remnants left behind)
• Reserved for small, unilocular cysts

• Carnoy's solution applied to the bony cavity for 3 minutes after enucleation
• Composition of Carnoy's Solution: Absolute alcohol (6 mL) + Chloroform (3 mL) + Glacial acetic acid (1 mL) + Ferric chloride (1 g)
• Penetrates 1.54 mm into bone, destroying residual epithelial cells and daughter cysts
• Significantly reduces recurrence rate to < 10%
• Contraindication: Do NOT apply near the inferior alveolar nerve (risk of nerve damage)

• After enucleation, the bony walls are removed to a depth of 1-2 mm using a bur or chisel
• Removes any residual epithelial remnants in bone
• Combined with Carnoy's solution for best results

• Creating a surgical window to allow decompression and shrinkage of the cyst
• Indications: Large cysts involving vital structures (inferior alveolar nerve, tooth roots), cysts approaching the maxillary sinus, in children (to preserve developing teeth)
• Reduces size of the cyst over months, followed by definitive enucleation
• Disadvantage: Leaves residual cyst lining

• Applied to the cyst cavity to destroy residual cells
• Reduced recurrence rates reported

• Indications:
  • Very large, recurrent OKCs
  • Multiple recurrences
  • OKC associated with Gorlin-Goltz syndrome
  • Radiologically aggressive with cortical perforation and soft tissue invasion
• Marginal resection - for smaller lesions in the body of mandible
• Segmental resection - for aggressive, large lesions in the ramus/condyle or recurrent cases
• Followed by reconstruction (bone graft, distraction osteogenesis, free flap)

• Immediate or delayed bone grafting using autogenous bone (iliac crest, rib) or alloplastic materials

Preferred Protocol (as per Nilima Malik):

Post-operative Follow-up:

• Long-term radiographic follow-up mandatory - minimum 5-10 years
• Annual OPG for at least 5 years
• Clinical examination at each visit for signs of recurrence

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Q2. Classify Mandibular Fractures. Describe in detail Signs, Symptoms, Radiological Features and Management of Bilateral Condylar Fracture.

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CLASSIFICATION OF MANDIBULAR FRACTURES

A. Based on Anatomical Location (Lindqvist / Most commonly used):

1. Symphysis (between the two central incisors)
2. Parasymphysis (between the canine and first premolar on either side)
3. Body (molar region - between the canine and the angle)
4. Angle (region of the third molar - from the distal aspect of second molar to the posterior attachment of masseter)
5. Ramus (between the sigmoid notch superiorly and the angle inferiorly)
6. Coronoid process
7. Condylar process
   • Head (intracapsular/diacapitular)
   • Neck (subcondylar)
   • Subcondylar (base of condyle)
8. Alveolar process

B. Based on Favorability (Direction of fracture line):

• Favorable: Muscle pull tends to keep the fragments in apposition
• Unfavorable: Muscle pull tends to distract the fragments
  • Vertically favorable / unfavorable
  • Horizontally favorable / unfavorable

C. Based on Nature of Fracture:

• Simple (Closed): Skin and mucosa intact
• Compound (Open): Communication with the oral cavity or external environment
• Comminuted: Multiple small fragments (due to high-velocity injury)
• Greenstick: Incomplete fracture, one cortex bent and the other broken (children)
• Pathological: Fracture through diseased bone (cyst, tumor, osteomyelitis)
• Impacted: Fragment driven into another

D. Based on Number:

• Single, Double, Multiple (ipsilateral), Bilateral

E. Based on Condylar Fractures (Spiessl Classification - widely used):

• Type I: Subcondylar fracture without displacement
• Type II: Low subcondylar fracture with displacement
• Type III: High subcondylar fracture with displacement
• Type IV: Low subcondylar fracture with dislocation
• Type V: High subcondylar fracture with dislocation
• Type VI: Intracapsular/diacapitular fracture

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BILATERAL CONDYLAR FRACTURE

• Indirect trauma: Force applied to the chin → transmitted posteriorly → impacts both condylar heads against the glenoid fossa
• Direct trauma: Less common
• Common in road traffic accidents, falls on the chin

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SIGNS AND SYMPTOMS

Symptoms (Patient Complaints):

1. Pain in the preauricular region bilaterally on opening the mouth
2. Difficulty in opening the mouth (limited mouth opening)
3. Malocclusion - "bite feels different"
4. Trismus (spasm of masticatory muscles)
5. Tenderness in front of both ears
6. Swelling in the preauricular region bilaterally
7. Bleeding from the external auditory meatus (hemotympanum) - if middle cranial fossa fractured

Signs (Clinical Examination):

1. Chin point deviation - in unilateral condylar fracture, the chin deviates to the fractured side; in bilateral condylar fractures, the chin deviates anteriorly (forward)
2. Preauricular swelling and tenderness bilaterally
3. Limitation of mouth opening (trismus)
4. Condylar movement reduced or absent bilaterally on palpation in front of the ears
5. Anterior open bite - pathognomonic of bilateral condylar fractures
   • Due to loss of vertical height of both rami, posterior teeth meet first, opening the anterior bite
6. Shortening of the face (reduction in lower face height)
7. Prognathic appearance - mandible may appear thrust forward
8. Battle's sign (bruising over mastoid) - suggests temporal bone/base of skull fracture

1. Anterior open bite - cannot bring anterior teeth into contact
2. Premature contact of posterior teeth bilaterally
3. Lacerations of the chin (if direct trauma)
4. Class III tendency of the occlusion
5. Pain on attempted closure of the teeth

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RADIOLOGICAL FEATURES

1. Orthopantomogram (OPG): Best single view for condylar fractures
   • Shows both condyles simultaneously
   • Reveals fracture line, displacement, and dislocation
   • Condylar head may appear shortened, tilted medially, or displaced anteriorly/medially
2. Posteroanterior (PA) view of the mandible (Reverse Towne's view):
   • Best shows medial/lateral displacement of condyle
   • Condyle displaced medially (most common)
3. Lateral oblique view (body/ramus)
4. Submentovertex view (base view)
5. Towne's projection: Shows condylar head in AP view
6. Trans-pharyngeal view (lateral transcranial/transpharyngeal)

• Axial and coronal sections
• Best for intracapsular fractures and assessing medial/anterior displacement
• 3D reconstruction for surgical planning
• Identifies associated fractures of the temporal bone, zygomatic arch, middle cranial fossa

• Fracture line through the condylar neck (subcondylar) bilaterally
• Shortening of condylar ramus height
• Medial and anterior displacement of condylar fragments (due to lateral pterygoid pull)
• Step deformity at fracture site
• Anterior open bite on clinical correlation

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MANAGEMENT OF BILATERAL CONDYLAR FRACTURE

General Principles:

1. Restore normal occlusion
2. Restore normal mandibular movement
3. Prevent ankylosis of the TMJ
4. Prevent condylar growth disturbance (especially in children)

Two Main Treatment Approaches:

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• Undisplaced or minimally displaced fractures
• Elderly patients with poor surgical risk
• Children (to avoid damage to condylar growth center)
• Intracapsular fractures
• Patients with edentulous jaws (with well-fitting dentures)

1. Intermaxillary Fixation (IMF) / Maxillo-mandibular Fixation (MMF):
   • Arch bars (Erich arch bar) placed on upper and lower teeth
   • Wires used to wire the jaws shut in correct occlusion
   • Duration: 2-3 weeks in adults; 10-14 days in children
   • Followed by vigorous physiotherapy to prevent ankylosis
   • Physiotherapy: Opening exercises, protrusive exercises, lateral excursions
2. Functional treatment (soft diet, physiotherapy):
   • For minimally displaced condylar fractures
   • Soft diet, analgesics, mouth-opening exercises
   • No fixation
3. Gunning splints (in edentulous patients) - connected by intermaxillary fixation

• Risk of ankylosis (especially in children)
• Malocclusion may persist
• Remodeling may be incomplete in adults
• Anterior open bite may persist

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• Displacement into middle cranial fossa
• Condyle displaced into external auditory meatus with obstruction
• Open joint injury with foreign body
• Lateral extracapsular displacement (especially in bilateral cases)

• Bilateral condylar fractures with associated comminuted midface fractures
• Inability to obtain satisfactory occlusion with closed treatment
• Bilateral fractures with anterior open bite not correctable conservatively
• Medically compromised patients unable to tolerate IMF (e.g., epileptics, respiratory issues)
• Condylar dislocation with severe displacement

1. Preauricular approach (Rowe and Killey) - most common for condylar head/neck
2. Retromandibular approach (Hinds and Girotti)
3. Submandibular approach (Risdon incision) - for low subcondylar fractures
4. Endoscopic approach - minimally invasive

• Miniplates and screws (Champy's principle)
• Single miniplate - for condylar neck fractures
• Two miniplates/lag screws - for high subcondylar
• Transosseous wiring

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Management Protocol for Bilateral Condylar Fractures (Summary):

Post-operative Care:

• IMF release at 2-3 weeks (closed) or at time of surgery (open)
• Physiotherapy: Jaw opening exercises, protrusive movements
• Soft diet for 4-6 weeks
• Regular clinical and radiographic follow-up
• Watch for: Ankylosis, condylar resorption, growth disturbance (children), facial asymmetry

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PART II - SHORT NOTES (5 marks each)

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SN 1. LeFort I Fracture and Management

Fracture Line (Anatomy):

• Anterior wall of the maxillary sinus
• Nasal septum (above the nasal floor)
• Pterygoid plates (lower third)
• Lateral walls of both maxillary sinuses

Clinical Features:

1. Edema of the upper lip and cheeks
2. Ecchymosis in the buccal vestibule
3. Epistaxis (nosebleed)
4. Step deformity in the buccal vestibule (along the fracture line)
5. Mobility of the palate and upper teeth as one unit when the upper alveolus is grasped and moved
6. Malocclusion - anterior open bite or posterior open bite depending on direction of displacement
7. Elongation of the midface (downward displacement) or dish-face deformity
8. Bilateral black eyes (periorbital ecchymosis)
9. Crepitation on manipulation
10. Subconjunctival hemorrhage

Radiological Features:

• OPG, PA skull, lateral skull views
• Fracture line visible above tooth apices
• CT scan (axial + coronal): Gold standard - shows exact fracture pattern, displacement, and involvement of pterygoid plates

Management:

• Disimpaction forceps (Rowe's disimpaction forceps) - placed in the nostrils and palate to disengage the impacted fragment
• Manual manipulation to reposition the maxilla

• Intermaxillary Fixation (IMF) using arch bars - for minimally displaced fractures
• Duration: 4-6 weeks

• Incisions: Maxillary vestibular incision (degloving incision), infraorbital incision
• Exposure of the fracture site
• Plate and screw fixation: Miniplates placed at:
  • Nasomaxillary buttress
  • Zygomaticomaxillary buttress
  • Frontal process of maxilla
• Advantage: Rigid fixation, no prolonged IMF required

• Soft diet for 4-6 weeks
• Oral hygiene
• Follow-up for occlusion and healing

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SN 2. Kaban's Protocol

Steps (Modified Kaban's Protocol - 7 Steps):

1. Aggressive resection of the ankylotic mass - removal of the fibrous/bony ankylotic mass and creation of a gap of at least 1.5 cm between the glenoid fossa and the ramus stump
2. Ipsilateral coronoidectomy - to release the coronoid process (removes secondary contracture and improves mouth opening)
3. Contralateral coronoidectomy (if needed) - if mouth opening is still < 35 mm after ipsilateral coronoidectomy
4. Lining the glenoid fossa with cartilage or a temporalis muscle/fascia flap - to prevent re-ankylosis and provide a gliding surface
5. Reconstruction of the ramus/condyle using:
   • Costochondral rib graft (in growing children - gold standard)
   • Total joint prosthesis (in adults)
   • Distraction osteogenesis
6. Rigid fixation with plates and screws
7. Early aggressive physiotherapy with mouth opening exercises (key to preventing recurrence)

Key Points:

• Coronoidectomy is performed only if mouth opening < 35 mm after ankylotic mass removal
• Costochondral rib graft is preferred in children as it has growth potential
• Physiotherapy must begin within 1-2 weeks post-surgery and continue for months
• The most common cause of recurrence is inadequate resection and poor physiotherapy compliance

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SN 3. Composition of Carnoy's Solution and Its Use

Composition:

Mechanism of Action:

• Acts as a fixative and chemical cauterizing agent
• Ferric chloride precipitates proteins
• Absolute alcohol denatures proteins and acts as a fixative
• Glacial acetic acid enhances protein precipitation
• Chloroform acts as a fat solvent/protein precipitant
• Penetration depth: approximately 1.54 mm into bone

Uses in Oral Surgery:

1. Odontogenic Keratocyst (OKC): Primary use - applied to the bone cavity after enucleation for 3 minutes to destroy residual epithelial cell rests, satellite cysts, and daughter cysts in the bone walls; significantly reduces recurrence rate
2. Dentigerous cyst - occasionally used
3. Ameloblastoma - after curettage in some cases
4. Recurring jaw cysts - as an adjunct to surgical treatment

Application Technique:

• After enucleation of the cyst, the cavity is dried
• Carnoy's solution is applied on a gauze swab/cotton pellet to the bony walls for exactly 3 minutes
• The cavity is then thoroughly irrigated with normal saline to wash out residual chemical
• The cavity is then packed or sutured primarily

Precautions:

• Protect the inferior alveolar nerve - do not apply in areas where the nerve is exposed (nerve necrosis can occur)
• Do not apply to soft tissues - causes chemical burn
• Protect surrounding soft tissues with Vaseline gauze
• Use in a well-ventilated area (chloroform is carcinogenic/toxic)

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SN 4. Boundaries of Canine Space and Its Contents

Canine Space (Canine Fossa Abscess):

Boundaries:

Contents of the Canine Space:

1. Infraorbital nerve and its branches (anterior superior alveolar branch, middle superior alveolar branch)
2. Infraorbital vessels (infraorbital artery and vein)
3. Angular vein (may traverse this space)
4. Fat (loose areolar tissue)
5. Levator anguli oris muscle (forms the posterior boundary)

Clinical Significance:

• Infection of the maxillary canine most commonly spreads to this space (as the canine root apex perforates the buccal cortex above the levator anguli oris muscle attachment)
• Presents as: Obliteration of nasolabial fold, swelling on the side of the nose and cheek (lifts the corner of the mouth)
• Cavernous sinus thrombosis - dangerous complication if infection spreads via the angular and ophthalmic veins (danger triangle of the face)
• Drainage: Intraoral (through mucobuccal fold incision in the canine fossa region) or extraoral (rarely, through the skin)

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SN 5. Various Extraoral Approaches to the Temporomandibular Joint

1. Preauricular Approach (Most Common)

• Incision: In the preauricular skin crease, extending from the root of the helix superiorly to the tragus inferiorly (Al-Kayat and Bramley modification adds temporal extension)
• Layers: Skin → subcutaneous tissue → superficial temporal fascia → periosteum → joint capsule
• Protection: Branches of the facial nerve (temporal and zygomatic branches) must be protected
• Uses: Condylotomy, condylectomy, arthroplasty, TMJ disc surgery, condylar fractures
• Advantage: Direct access to the joint, hidden scar
• Disadvantage: Risk to temporal branch of facial nerve

2. Endaural Approach (Rowe)

• Incision: Within the external auditory canal, along the tragus
• Modified to avoid scar in the preauricular crease
• Disadvantage: Limited access, risk to external auditory canal

3. Postauricular Approach

• Incision posterior to the ear
• Rarely used for TMJ; mainly in combined procedures

4. Submandibular / Risdon Approach

• Incision: 2 cm below the lower border of the mandible (to protect the marginal mandibular branch of the facial nerve)
• Used for: Low condylar/subcondylar fractures, condylar neck fractures
• Disadvantage: Indirect access to the condylar head

5. Retromandibular / Transparotid Approach (Hinds and Girotti)

• Incision: 0.5 cm below the earlobe, behind the posterior border of the ramus
• Passes through (or around) the parotid gland
• Used for: Subcondylar fractures, condylar neck fractures (excellent direct access)
• Advantage: Direct view of condylar neck, good access for plate placement
• Disadvantage: Risk to facial nerve branches (marginal mandibular, cervical)

6. Temporal (Gillie's) Approach (for Zygomatic Arch - mentioned separately)

• Incision in the temporal hairline
• Elevator passed deep to the temporal fascia to elevate depressed zygomatic arch fractures

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SN 6. Kelsey Fry's Technique

Description:

Steps:

1. A 0.4 mm (26 gauge) stainless steel soft wire is used
2. The wire is folded into a loop (eyelet) and passed around the neck of each tooth
3. One end is passed through the contact point mesially, the other distally
4. Both ends are twisted together to form a firm loop (eyelet) on the labial/buccal surface
5. Eyelets are placed on both upper and lower arches (typically 3-4 per quadrant - canine, first premolar, first molar)
6. Upper and lower eyelets are then connected by intermaxillary fixation wires to achieve jaw fixation in correct occlusion

Advantages:

• Simple, inexpensive technique
• Can be done under local anesthesia
• No special equipment needed
• Good for edentulous areas (teeth are used as anchor points)

Disadvantages:

• Limited to dentate patients
• Individual teeth must be strong enough to withstand the forces
• Time-consuming if many eyelets needed
• Does not provide as rigid fixation as arch bars

Uses:

• IMF for undisplaced/minimally displaced mandibular fractures
• Adjunct to other fixation methods
• Simple jaw stabilization

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SN 7. Garré's Osteomyelitis (Chronic Nonsuppurative Sclerosing Osteomyelitis / Periostitis Ossificans)

Etiology:

• Most commonly caused by an infected lower first molar (especially one with caries or periapical abscess) in children/young adults
• Low-grade, chronic infection stimulates the periosteum to form new bone (subperiosteal bone apposition)

Epidemiology:

• Children and young adults (< 25 years)
• Mandible predominantly (especially the body and angle region)
• Maxilla is rarely involved

Clinical Features:

1. Bony hard swelling on the lower border of the mandible - non-tender or mildly tender
2. Swelling is firm, hard, and non-fluctuant
3. No pus formation (non-suppurative)
4. Minimal pain (low-grade chronic course)
5. Associated tooth is usually carious or non-vital
6. No fever or lymphadenopathy (unless acute exacerbation)
7. Trismus may be present in some cases

Radiographic Features:

• Periosteal new bone formation seen on the lower border of the mandible
• Layers of new periosteal bone laid parallel to each other
• Resembles the layered appearance of an onion
• May show a zone of rarefaction (original osteomyelitic focus) within or above the periosteal reaction
• Cortical thickening and sclerosis

Histopathology:

• Multiple layers of new bone formation
• Vital bone with active osteoblasts
• Periosteum is thickened with chronic inflammatory infiltrate

Management:

1. Treat the causative tooth:
   • Extraction of the infected tooth OR endodontic treatment (root canal treatment) - this is the primary treatment
   • Removal of the source of infection allows the periosteal bone to remodel and the swelling to resolve
2. Antibiotics: Amoxicillin or penicillin V for 7-10 days
3. Surgical debridement: Only if simple removal of the offending tooth does not resolve the condition
4. Follow-up radiographs: The periosteal new bone typically remodels and the jaw returns to normal contour within months after infection is eliminated
5. Decortication - rarely needed for severe cases

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SN 8. Genioplasty

Indications:

• Microgenia (small chin) - most common
• Macrogenia (large chin)
• Asymmetric chin
• Retrognenia (setback of the chin)
• Prognenia (protrusion of the chin)
• As part of orthognathic surgery (combined with BSSO or LeFort I)
• Vertical chin deformities (vertical excess or deficiency)

Types of Genioplasty:

• An osteotomy is made through the chin bone below the mental foramina (to protect the mental nerve)
• The chin segment is repositioned:
  • Advancement - moved forward (for microgenia)
  • Setback - moved posteriorly
  • Superior repositioning - moved upward (for vertical excess)
  • Inferior repositioning - moved downward (lengthening, for vertical deficiency)
  • Lateral repositioning - for asymmetry
• Fixed with plates and screws (titanium miniplates)

• Insertion of a chin implant (silicone or Medpor) to augment chin projection
• Simpler procedure, no osteotomy
• Risk of bone resorption under the implant

Surgical Steps (Sliding Genioplasty):

1. Intraoral approach: Horizontal incision in the lower labial vestibule (10-15 mm below gingival margin)
2. Subperiosteal dissection to expose the chin
3. Identification and protection of mental nerves bilaterally
4. Horizontal osteotomy made below the mental foramina using a reciprocating saw
5. Repositioning of the chin segment in the desired direction
6. Fixation with titanium miniplate(s)
7. Wound closure in layers

Complications:

• Mental nerve paresthesia (most common)
• Hematoma
• Infection
• Plate exposure
• Relapse
• Ptosis of the chin pad (witch's chin deformity)
• Asymmetry

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SN 9. Anterior Superior Alveolar Nerve Block (ASAN Block)

Nerve Supply:

• Upper central and lateral incisors
• Upper canine
• Buccal gingiva of these teeth
• Sometimes the premolars (via communication with middle superior alveolar nerve)

Two Techniques:

A. Intraoral Technique (Labial Approach):

1. Patient seated with head tilted back, mouth slightly open
2. Retract upper lip to expose the maxillary labial vestibule
3. Injection site: Mucobuccal fold at the level of the canine or first premolar on the side to be blocked
4. Insert needle at 45 degrees directed toward the infraorbital foramen (palpate the infraorbital notch to locate)
5. Advance the needle approximately 1.5-2 cm superiorly toward the infraorbital foramen
6. Aspirate - if negative, deposit 1-1.5 mL of local anesthetic slowly
7. The LA diffuses to block the ASA nerve as it exits the infraorbital foramen

B. Extraoral Technique (Cutaneous):

1. Infraorbital foramen is palpated on the face (approximately 1 cm below the infraorbital rim, in line with the pupil)
2. Needle inserted through skin directed toward the infraorbital foramen
3. LA deposited

Area Anesthetized:

• Upper incisors, canine, and sometimes first premolar
• Buccal gingiva of these teeth
• Upper lip (partial)
• Lower eyelid and part of the nose (if infraorbital nerve is fully blocked)

Uses:

• Extraction of upper anterior teeth
• Anterior maxillary surgical procedures
• Repair of upper lip lacerations

Precautions:

• Do not enter the infraorbital foramen (risk of nerve damage)
• Aspirate before injection
• Compress the area after injection for 2 minutes to encourage diffusion

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SN 10. Ashley's Flap

Also called: Bichat's fat pad flap / Buccal Fat Pad (BFP) flap

Anatomy:

• The buccal fat pad (corpus adiposum buccae) lies in the buccal space, superficial to the buccinator muscle
• It has a central body and four processes: temporal, pterygoid, pterygomandibular, and buccal
• Rich blood supply from branches of the facial, maxillary, and transverse facial arteries

Indications:

1. Closure of oroantral fistulas (OAF) - especially in the posterior maxilla
2. Closure of oroantral communications after tooth extraction
3. Palatal defects
4. Large buccal defects after tumor excision
5. When local flaps (buccal advancement flap, palatal rotation flap) are not feasible

Surgical Technique:

1. Incision along the upper buccal vestibule above the fistula
2. Retraction of the mucosal flaps
3. Incision through the buccinator muscle (if needed) posterior to the fistula
4. The buccal fat pad is gently delivered into the oral cavity - it herniates out easily due to fat lobule architecture
5. The fat pad is advanced and rotated to cover the oroantral defect
6. Secured with interrupted absorbable sutures to the palatal mucosa
7. The buccal fat pad epithelializes over 3-4 weeks by secondary intention

Advantages:

• Excellent vascularity - highly reliable flap
• Simple technique with no donor site morbidity
• No secondary scar on the palate (unlike palatal rotation flap)
• Can close defects up to 4 cm in diameter
• The fat epithelializes naturally - no need for primary epithelial cover

Disadvantages:

• Limited reach - restricted by the pedicle
• Slight depression in the cheek (usually not significant)
• Not suitable for large, extensive defects
• Risk of hematoma in the buccal space

Healing:

• The exposed fat pad epithelializes within 3-4 weeks
• Final scar is inconspicuous

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COMPLETE ANSWER SUMMARY - AUGUST 2016 PAPER

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PART I - LONG ESSAYS

• Definition of cyst: A pathological epithelium-lined cavity with fluid/semi-fluid contents, not created by pus
• Classification of odontogenic cysts: Developmental (OKC, dentigerous, eruption, lateral periodontal, calcifying OC, glandular OC, gingival cysts) vs. Inflammatory (radicular, residual, paradental)
• OKC clinical features: 2nd-3rd decade, male predominance, posterior mandible (angle/ramus), often asymptomatic, anteroposterior growth pattern, thin lining prone to perforation, cheesy keratin contents on aspiration
• Radiographic features: Well-defined unilocular/multilocular radiolucency, scalloped margins with corticated border, minimal expansion, associated with unerupted teeth
• Histopathology: 6-8 cell thick parakeratinized epithelium, palisaded "tombstone" basal cells, flat interface, satellite cysts - pathognomonic
• Management: Enucleation + Carnoy's solution (primary); Marsupialization for large cysts; Peripheral ostectomy; Resection for recurrent/aggressive cases; 5-10 year follow-up mandatory

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• Classification of mandibular fractures: By site (symphysis, parasymphysis, body, angle, ramus, condyle, coronoid, alveolus), favorability, nature (simple, compound, comminuted, greenstick, pathological), and Spiessl classification for condylar fractures
• Signs/symptoms: Anterior open bite (pathognomonic), bilateral preauricular pain/swelling, limited mouth opening, bilateral condylar immobility, chin displaced anteriorly, premature posterior contact, posterior teeth contact first
• Radiological features: OPG (best single view), Reverse Towne's view for medial displacement, CT scan (gold standard) - condylar head shortening, medial displacement, fracture line subcondylar
• Management: Closed treatment (IMF 2-3 weeks + physiotherapy) for undisplaced/children; ORIF (preauricular/retromandibular approach + miniplate fixation) for displaced fractures with malocclusion, anterior open bite not correctable conservatively, or bilateral fractures with midface injuries

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PART II - SHORT NOTES

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AUGUST 2016 — SHORT NOTES (5 marks each)

Reference: Scott-Brown's Otorhinolaryngology Head & Neck Surgery | Cummings Otolaryngology | Mulholland & Greenfield's Surgery

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SHORT NOTE 1: LeFort I Fracture and Management

Fracture Line:

• Anterior and lateral walls of both maxillary sinuses
• Nasal septum (lower third)
• Lower third of the pterygoid plates
• Separates the alveolar process + hard palate + lower maxilla from the skull base

Diagram — LeFort Fracture Lines (from Scott-Brown's Otorhinolaryngology):

Clinical Features:

Management:

• Rowe's disimpaction forceps - one blade in nostril, one on palate - used to disengage the impacted fragment

• Manual repositioning of the maxilla into correct occlusion

• IMF only (for minimally displaced): Erich arch bars + IMF wires, 4-6 weeks
• ORIF (preferred): Miniplates placed at the 4 maxillary buttresses:
  • Right and left nasomaxillary buttresses (piriform rim)
  • Right and left zygomaticomaxillary buttresses (infrazygomatic region)
• Approach: Maxillary vestibular (degloving) incision
• Post-op: Soft diet 6 weeks, oral hygiene

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SHORT NOTE 2: Kaban's Protocol (7-Step Protocol for TMJ Ankylosis)

The 7 Steps:

Key Points:

• Coronoidectomy is step 2 but step 3 is conditional on mouth opening < 35 mm
• Costochondral graft is gold standard in children (growth potential of rib cartilage)
• Most common cause of failure/recurrence: Inadequate resection + poor physiotherapy compliance
• Preauricular/endaural incision is typically used for access

Diagram — Condylectomy and Preauricular Incision (for TMJ access):

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SHORT NOTE 3: Composition of Carnoy's Solution and Its Use

Composition:

Modified Carnoy's Solution = same formula but without chloroform (used to avoid chloroform toxicity/carcinogenicity)

Mechanism of Action:

• Ferric chloride — precipitates proteins, coagulates tissue
• Absolute alcohol — fixes and denatures proteins, kills cells
• Glacial acetic acid — enhances protein precipitation
• Chloroform — dissolves fat, precipitates proteins
• Penetration depth into bone: ~1.54 mm

Primary Use — Odontogenic Keratocyst (OKC):

Application Technique:

1. Enucleate the cyst completely
2. Dry the bony cavity thoroughly
3. Protect the inferior alveolar nerve with a gauze strip (Vaseline gauze over nerve)
4. Apply Carnoy's solution on cotton pellet/gauze to bone walls for exactly 3 minutes
5. Irrigate thoroughly with normal saline
6. Close primarily or pack with iodoform gauze

Other Uses:

• Dentigerous cyst (adjunct)
• Recurring jaw cysts
• Ameloblastoma (after conservative surgery, selected cases)

Precautions:

• NEVER apply near the inferior alveolar nerve — causes irreversible nerve necrosis
• Do not contact soft tissues — chemical burn
• Chloroform is carcinogenic — use in ventilated area; some centers now use Modified Carnoy's (without chloroform)

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SHORT NOTE 4: Boundaries of Canine Space and Its Contents

Boundaries:

Contents:

1. Infraorbital nerve (anterior superior alveolar branch exits into this space)
2. Infraorbital vessels (infraorbital artery and vein)
3. Angular vessels (angular artery and vein — terminal branch of facial artery/vein)
4. Loose areolar connective tissue and fat

How Infection Reaches This Space:

• The apex of the maxillary canine penetrates the buccal cortex above the attachment of the levator anguli oris muscle → infection tracks superiorly into the canine space

Clinical Features of Canine Space Infection:

• Obliteration of the nasolabial fold (most characteristic sign)
• Swelling of the side of the nose, upper lip, and cheek
• Elevation of the corner of the mouth
• Edema around the infraorbital region

Clinical Significance - Danger:

• Angular vein → ophthalmic vein → cavernous sinus = risk of cavernous sinus thrombosis
• This is why canine space infections in the danger triangle of the face must be treated aggressively

Drainage:

• Intraoral drainage preferred: Incision in the mucobuccal fold at the canine fossa level
• Rarely: Extraoral drainage through skin

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SHORT NOTE 5: Various Extraoral Approaches to the Temporomandibular Joint

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1. Preauricular Approach (Most Common)

• Incision: In the preauricular skin crease from root of helix to tragus; may extend into temporal hairline (Al-Kayat and Bramley modification)
• Plane of dissection: Through skin → subcutaneous tissue → temporal fascia (superficial layer) → periosteum → joint capsule
• Risk: Temporal branch of facial nerve (VII)
• Uses: Condylotomy, condylectomy, disc surgery, arthroplasty, condylar ORIF
• Advantage: Hidden scar, direct joint access

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2. Endaural Approach

• Incision: Along the anterior tragus and into the base of the concha
• Avoids preauricular scar
• Limited access; risk of scarring in external auditory canal
• Less commonly used today

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3. Submandibular Approach (Risdon's Incision)

• Incision: 1.5-2 cm below the inferior border of mandible (to protect marginal mandibular nerve)
• Uses: Low subcondylar fractures, condylar neck fractures — excellent for miniplate fixation
• Advantage: Good access to condylar neck/subcondylar region
• Risk: Marginal mandibular branch of facial nerve; scar visible

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4. Retromandibular Transparotid Approach (Hinds and Girotti)

• Incision: 0.5-1 cm below the earlobe, along the posterior border of mandibular ramus
• Passes through the parotid gland substance (transparotid) or around it (retroparotid variant)
• Uses: Subcondylar and condylar neck fractures — best direct access for ORIF with miniplate
• Risk: Facial nerve branches (marginal mandibular, cervical branches)
• Advantage: Excellent direct visualization of condylar neck, minimal dissection

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5. Postauricular (Retroauricular) Approach

• Incision: Behind the ear, in the retroauricular sulcus
• Rarely used for the TMJ alone; more used in combined ear-TMJ surgery
• Limited access

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Summary Table:

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SHORT NOTE 6: Kelsey Fry's Technique

Materials:

• 26-gauge (0.4 mm) soft stainless steel wire
• Wire is bent into a loop (eyelet) around a 3 mm rod

Steps of the Technique:

1. Take a piece of 26G wire (approx. 15 cm)
2. Fold the wire in half around a 3 mm diameter rod → creates a circular loop (eyelet)
3. Give 3-4 twists to the loop to secure it
4. Cut the ends obliquely to create sharp points for easy passage through contact points

1. Pass one end through the mesial contact point and the other through the distal contact point of the chosen tooth
2. Pass the distal wire end through the eyelet loop
3. Pass the mesial wire end beneath the distal shaft
4. Pull tight and twist together on the buccal surface to secure the eyelet firmly around the tooth neck
5. Trim and tuck the ends

• Eyelets placed on 3-4 teeth in both upper and lower arches (usually: upper canine, upper first molar and lower canine, lower first molar bilaterally)
• IMF wires or elastic bands then passed between the upper and lower eyelets to fix the jaws in occlusion

Diagram — Mandibular fracture sites and wiring (Jaypee oral surgery textbook):

Advantages:

• Simple, quick, inexpensive
• Can be done under local anesthesia
• No special instruments needed

Disadvantages:

• Less rigid than arch bars
• Only works in dentate patients with strong teeth
• Individual teeth must be periodontally sound
• Time-consuming if many eyelets are required

Uses:

• Temporary IMF for undisplaced/minimally displaced mandibular fractures
• Simple jaw stabilization before definitive treatment
• Combined with other fixation methods

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SHORT NOTE 7: Garré's Osteomyelitis

Epidemiology:

• Age: Children and young adults (predominantly < 25 years)
• Sex: Equal
• Site: Mandible (body and angle region, almost exclusively); maxilla is rarely involved

Etiology:

• Most commonly an infected, carious lower first molar with periapical pathology
• Low-grade chronic infection stimulates the periosteum → reactive new bone formation
• No pus formation — low virulence organisms

Clinical Features:

1. Hard, bony, non-tender swelling on the lower border of the mandible — firm and non-fluctuant
2. No pus or sinus tract (non-suppurative)
3. Minimal or no pain (chronic low-grade)
4. No fever, no lymphadenopathy (unless acute exacerbation)
5. Carious or non-vital lower first molar is almost always identified
6. Trismus — may be present
7. Jaw may appear asymmetrically enlarged

Radiographic Features:

• Multiple parallel layers of new periosteal bone visible along the lower and outer cortex of the mandible
• Layers are parallel to the original cortex, creating a laminated pattern resembling the layers of an onion
• May also show: cortical thickening, zone of rarefaction (original infection focus) at the root apex of the offending tooth

Histopathology:

• Multiple laminated layers of new bone
• Active osteoblasts lining bone surfaces
• Thickened periosteum with chronic inflammatory infiltrate
• No necrotic bone or pus

Management:

1. Eliminate the source of infection (primary treatment):
   • Extraction of the offending (carious, non-vital) tooth — usually the lower first molar
   • OR Root canal treatment if tooth is salvageable
2. Antibiotics: Amoxicillin 500mg TDS × 7-10 days (or Penicillin V)
3. Follow-up radiographs: Periosteal new bone remodels and resolves over 6-12 months after infection removal
4. Surgical debridement/decortication is rarely needed

Prognosis: Excellent. After removal of the offending tooth, the jaw remodels to near-normal contour.

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SHORT NOTE 8: Genioplasty

Indications:

• Microgenia (underdeveloped/small chin) — most common
• Retrogenia (chin set too far back)
• Progenia (excessive chin protrusion)
• Vertical chin excess or deficiency
• Chin asymmetry
• As part of orthognathic surgery (combined with BSSO or LeFort I)

Types (Cummings Otolaryngology):

Osseous (Sliding) Genioplasty — Surgical Steps:

1. Incision: Horizontal gingivolabial incision from canine to canine, on the labial side of the gingivolabial sulcus (to preserve adequate soft tissue cuff for closure)
2. Subperiosteal dissection: Elevate the periosteum to expose the anterior mandible; identify and protect both mental nerves bilaterally
3. Osteotomy marking: Mark the osteotomy line at least 5 mm below the mental foramina (to protect the mental nerve and its anterior loop)
4. Osteotomy: Horizontal osteotomy made with a reciprocating or oscillating saw through the full thickness of the chin bone
5. Repositioning: Move the freed chin segment:
   • Forward (advancement) for microgenia
   • Superiorly (impaction) for vertical excess
   • Inferiorly with bone graft for vertical deficiency
   • Laterally for asymmetry correction
6. Fixation: Titanium miniplate(s) and screws to rigidly fix the repositioned segment
7. Wound closure: In layers — periosteum, muscle, mucosa

Complications:

• Mental nerve paresthesia (most common - usually transient)
• Hematoma / seroma
• Infection
• Relapse / resorption
• Witch's chin deformity (ptosis of chin pad — if mentalis muscle not properly resuspended)
• Asymmetry

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SHORT NOTE 9: Anterior Superior Alveolar Nerve Block (ASAN Block)

Nerve Anatomy:

• The ASA nerve is a branch of the infraorbital nerve (V2)
• Exits from the infraorbital foramen (located ~1 cm below the infraorbital rim, in line with the pupil)
• Supplies: Upper central incisors, lateral incisors, canine (and communicates with middle superior alveolar nerve)
• Also supplies: Buccal gingiva of these teeth, upper lip, part of nasal floor

Landmarks:

• Infraorbital foramen: ~1 cm below the infraorbital rim, in the mid-pupillary line
• Injection site (intraoral): Mucobuccal fold at the level of the upper canine or first premolar on the side to be blocked

Technique (Intraoral / Labial Approach):

1. Retract the upper lip to expose the mucobuccal fold
2. Insert the needle at the height of the canine/first premolar mucobuccal fold at approximately 45°, directed superiorly toward the infraorbital foramen
3. Advance the needle 1.5-2 cm superiorly while keeping close to bone
4. Aspirate — if negative, slowly deposit 1-1.5 mL of local anesthetic
5. Maintain gentle pressure on the skin over the infraorbital foramen during injection to promote diffusion
6. The LA solution diffuses around the infraorbital foramen, blocking the ASA nerve

Area Anesthetized:

• Upper central and lateral incisors and canine (pulp + periodontium)
• Buccal gingiva of above teeth
• Upper lip
• Part of the nose and lower eyelid (if full infraorbital nerve blocked)

Uses:

• Extraction of upper anterior teeth
• Anterior maxillary surgical procedures (apicectomy, cyst enucleation)
• Repair of upper lip and anterior vestibule lacerations
• Anterior ridge surgery / alveoloplasty in premaxilla

Precautions:

• Do NOT insert needle into the infraorbital foramen (risk of nerve damage and orbital hematoma)
• Always aspirate before injection
• Limit to 1.5 mL to avoid spreading to infraorbital region causing lower eyelid anesthesia

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SHORT NOTE 10: Ashley's Flap (Buccal Fat Pad Flap)

Anatomy of the Buccal Fat Pad:

• A lobulated adipose structure lying in the buccal space, superficial to the buccinator muscle
• Has a central body and 4 processes: buccal, temporal, pterygoid, pterygomandibular
• Blood supply: Branches of the facial artery, maxillary artery, and transverse facial artery (excellent and reliable vascularity)
• Average volume: 9-10 mL per side

Indications:

1. Closure of oroantral fistulas (primary indication) — especially in the posterior maxilla (molar region)
2. Closure of oroantral communication after tooth extraction (when local mucoperiosteal flaps fail or are inadequate)
3. Coverage of palatal defects (after tumor resection)
4. Closure of oro-nasal fistulas
5. Large buccal mucosal defects following tumor excision
6. When buccal advancement flap or palatal rotation flap is not available

Surgical Technique:

1. Administer local anesthesia; prepare the surgical site
2. Incise along the upper buccal vestibule above the fistula
3. Reflect mucoperiosteal flaps to expose the buccal cortex
4. Make a small incision through the buccinator muscle in the molar/retromolar region (posterior to the fistula)
5. The buccal fat pad herniates readily through this opening — gently deliver it into the oral cavity using fine forceps or gentle pressure; do NOT pull forcefully (disrupts blood supply)
6. Advance and rotate the fat pad over the oroantral defect
7. Secure with interrupted absorbable sutures (3-0 Vicryl) to the surrounding palatal and buccal mucosa
8. The exposed fat pad surface is left exposed — it epithelializes by secondary intention over 3-4 weeks

Advantages:

• Reliable, well-vascularized flap — very high success rate
• Can close defects up to 4 cm in diameter
• No palatal scarring (unlike palatal rotation flap)
• No donor site scar (intraoral approach)
• Technique is relatively simple
• Fat pad regenerates well; cheek contour not significantly affected

Disadvantages:

• Limited reach dictated by pedicle length
• Cannot cover very large or extensive defects
• Slight transient cheek fullness reduction post-operatively
• Risk of hematoma in the buccal space

Healing:

• The exposed fat lobules epithelialize within 3-4 weeks by secondary intention
• Final result: well-closed defect with no visible scar

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AUGUST 2016 — SHORT NOTES SUMMARY