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PRE-PROSTHETIC & IMPLANT SURGERY

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1. Torus

• Torus palatinus - midline of hard palate; most common; lobular, flat, or nodular
• Torus mandibularis - lingual surface of mandible in premolar region; often bilateral

• Smooth, hard, non-tender, covered by thin mucosa
• Slow-growing; present in adults
• Asymptomatic unless traumatized

1. Interferes with denture construction
2. Repeated ulceration from trauma
3. Interferes with speech/swallowing
4. Patient request

• Midline incision for palatal torus; envelope flap for mandibular torus
• Bur/osteotome used to reduce the bony mass
• Mucoperiosteal flap raised and repositioned after removal

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2. Alveoloplasty

• Irregular, sharp, or undercut ridges
• Reduction of prominent tuberosities
• Removal of sharp bony spicules post-extraction

1. Simple/intraseptal alveoloplasty (Dean's alveoloplasty) - removal of the interseptal bone, collapsing the buccal plate inward; preserves maximum bone height
2. Radical alveoloplasty - more aggressive bone removal; used when the ridge is severely irregular

• Interseptal bone is removed after multiple extractions
• Buccal cortical plate is compressed inward
• Preserves the cortical plate as a covering for the ridge
• Advantage: maintains ridge height; heals faster

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3. Pre-Prosthetic Surgeries

• Adequate bone volume
• Adequate soft tissue
• Eliminate pathology
• Improve retention and stability

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4. Ridge Augmentation Procedures

• Guided bone regeneration (GBR) with membranes
• Onlay bone grafts
• Split crest/ridge expansion technique

• Distraction osteogenesis
• Block bone grafts (autogenous)
• GBR with tent-pole technique

• Autogenous: symphysis, ramus, iliac crest, tibial plateau (gold standard)
• Allograft: freeze-dried bone allograft (FDBA), demineralized FDBA
• Xenograft: Bio-Oss (bovine); provides scaffold
• Alloplastic: hydroxyapatite, beta-TCP, calcium sulfate

• Subepithelial connective tissue graft
• Onlay grafts to improve soft tissue contour

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5. Genioplasty

• Microgenia (small chin)
• Retrogenia (posteriorly positioned chin)
• Chin asymmetry
• Part of orthognathic surgery planning

1. Augmentation genioplasty - alloplastic chin implant or sliding osteotomy moved anteriorly
2. Reduction genioplasty - excess bone removed (bur/saw)
3. Sliding genioplasty (osseous genioplasty) - horizontal osteotomy below the mental foramen; segment moved anteriorly, posteriorly, superiorly, or inferiorly and fixed with titanium plates

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6. Vestibuloplasty

• Shallow vestibule preventing adequate denture flange extension
• Muscle attachments close to the crest of the ridge

1. Submucosal vestibuloplasty - submucous tissue excised; mucosa repositioned inferiorly
2. Secondary epithelialization vestibuloplasty (Kazanjian) - mucosal flap raised, periosteum exposed; healing by secondary intention; most common for mandible
3. Edlan-Mejchar vestibuloplasty - transposition of labial mucosa and mental muscle; for mandibular anterior region
4. Clark's vestibuloplasty - maxillary; mucosal split-thickness graft from palate placed in the deepened sulcus
5. Skin graft vestibuloplasty - used when large area needs coverage; less popular

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7. Implants (Dental Implants)

• Endosseous (endosteal) - placed within bone; most common; root-form or blade
• Subperiosteal - custom cast metal framework placed under periosteum but on top of bone; for severely resorbed ridges
• Transosteal - passes through the entire mandible; rarely used today (staple implant)

• Cylindrical/root-form (screw, press-fit)
• Blade/plate form
• Ramus frame implant

• Titanium (pure/alloy) - most common; excellent osseointegration
• Zirconia - tooth-colored, metal-free option

• Machined (smooth)
• Sand-blasted acid-etched (SLA) - enhanced osseointegration
• Hydroxyapatite-coated

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8. Osseointegration

1. Biocompatible material - titanium is the gold standard
2. Implant design - threaded, rough surface improves contact
3. Surgical technique - atraumatic surgery; no overheating (irrigation with saline, low-speed drilling)
4. Primary stability - good initial mechanical fixation (torque >35 Ncm ideal)
5. Adequate healing time - 3-6 months (mandible faster than maxilla)
6. Controlled loading - avoid premature/excessive loading

1. Blood clot formation and early inflammatory response
2. Woven bone formation (primary bone)
3. Lamellar bone remodeling (secondary bone - direct bone contact)

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MISCELLANEOUS TOPICS

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9. Frenectomy [2M]

• Labial frenum (maxillary/mandibular)
• Lingual frenum (causing ankyloglossia)
• Buccal frenum

• Midline diastema (high attachment of maxillary labial frenum)
• Ankyloglossia (tongue-tie) limiting tongue movement
• Interference with denture stability
• Periodontal problems (frenum pull on gingival margin)

1. Classic (excision) technique - V-shaped excision of frenum with closure; simple
2. Z-plasty technique - Z-shaped incision; provides more tissue for closure; preferred for lingual frenum (reduces scar contracture)
3. Localized frenectomy - frenectomy with removal of the papilla between central incisors (indicated for diastema cases)

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10. Gap Arthroplasty

• Preauricular or endaural approach
• Ankylotic mass resected; a gap of at least 1.5 cm created
• Gap may be left to fill with scar tissue (fibrous union) OR lined with interpositional material

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11. Interpositional Arthroplasty

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12. Re-implantation

• Hank's Balanced Salt Solution (HBSS) - best
• Milk - most practical
• Saliva (buccal vestibule)
• Saline
• Water - worst (causes cell lysis)

1. Gently rinse root with saline (do NOT scrub)
2. Local anesthesia; irrigate socket
3. Replant with gentle finger pressure
4. Flexible splint for 2 weeks
5. Antibiotic cover (doxycycline/amoxicillin)
6. Tetanus prophylaxis if contaminated
7. Root canal treatment within 7-10 days (for mature apex); immature apex - monitor for revascularization

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13. Transplantation of Tooth

• Premolar transplanted to replace congenitally missing upper incisor
• Third molar transplanted to replace a first molar
• Immature teeth (open apex) - best prognosis as revascularization can occur

• Recipient site prepared to match donor tooth dimensions
• Tooth extracted atraumatically
• Placed in new socket; flexible splint for 2-4 weeks
• Root canal may or may not be needed depending on apex maturity

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14. Dean's Alveoloplasty

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15. Classification of Dental Implants

1. Endosseous (endosteal) - within bone (most common)
2. Subperiosteal - on bone, under periosteum
3. Transosteal - through bone

1. Root-form (cylindrical/screw-shaped) - standard
2. Blade/plate-form
3. Ramus frame
4. Mini implants

1. One-stage (non-submerged)
2. Two-stage (submerged)

1. Machined/smooth
2. Acid-etched
3. Sandblasted + acid-etched (SLA)
4. Hydroxyapatite-coated
5. TiUnite (anodized)

1. Titanium (commercially pure / Ti-6Al-4V alloy)
2. Zirconia

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TMJ & FACIAL PAIN DISORDERS

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16. Define & Classify Ankylosis of TMJ. Discuss Clinical, Radiographic Features & Management of Bilateral Ankylosis in an 8-year-old Child

• Fibrous - fibrous tissue union; some mouth opening possible
• Bony - bony fusion; complete loss of movement
• Fibro-osseous - mixed

• Intra-articular (true ankylosis) - within the joint
• Extra-articular (false ankylosis/pseudoankylosis) - outside the joint (e.g., coronoid hyperplasia, fibrosis of muscles, depressed zygomatic arch)

• Unilateral or bilateral

• Type I - Fibrous ankylosis; condylar head present
• Type II - Bony bridge between condyle and coronoid/zygomatic arch; joint space partially visible
• Type III - Bony bridge between condyle and coronoid/zygomatic arch; joint space obliterated
• Type IV - Complete replacement of ramus-condyle unit by bone; bony block extending to skull base

• Trauma (most common in children) - condylar fracture
• Infection - septic arthritis, otitis media spreading to joint
• Systemic disease - rheumatoid arthritis, ankylosing spondylitis
• Neonatal forceps injury

• Complete inability to open mouth (trismus); mouth opening < 5 mm
• Difficulty eating, speaking, oral hygiene
• Recurrent aspiration; nutritional deficiency

• Micrognathia (small mandible) - failure of condylar growth center
• Bird face deformity - severely retruded chin, Class II skeletal pattern
• Anterior open bite - inability of mandible to grow forward
• Crossbite
• Dental crowding - teeth do not erupt normally
• Sleep apnea / airway compromise - in severe cases

• Poor oral hygiene, caries
• Drooling
• Psychological impact

• OPG/Lateral skull view: loss of joint space, bony mass replacing condyle
• CT (most useful): shows exact extent of ankylosis, bony mass, coronoid involvement
• Findings: obliteration of joint space, mushroom-shaped/flattened condyle, bony fusion with temporal bone, elongated coronoid process
• MRI: for fibrous ankylosis (shows soft tissue detail)

1. Gap arthroplasty (with interpositional material)
   • Minimum 1.5 cm gap created
   • Interpositional material: temporalis myofascial flap (preferred in children), or costochondral graft
2. Costochondral graft (CCG) - preferred in growing children
   • Rib cartilage with bone provides a growth potential (functions as a new condyle)
   • Provides structural support + allows facial growth
   • Placed at the site of the excised ramus-condyle unit
3. Total joint prosthesis - NOT used in growing children (no growth potential; requires revision as child grows)
4. Bilateral coronoidectomy/coronoidotomy - performed in addition to ankylosis release to improve mouth opening and reduce relapse

• Aggressive physiotherapy starting Day 1 post-op
• Mouth-opening exercises (Therabite/stacked tongue depressors)
• Minimum 30-35 mm mouth opening target
• Long-term follow-up for growth monitoring

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17. Trigeminal Neuralgia (Tic Douloureux)

• Paroxysmal, lancinating (electric shock-like) pain
• Unilateral (right > left); V2/V3 distribution most common (V1 rare)
• Duration: seconds to 2 minutes
• Triggered by touch, chewing, talking, cold air, brushing teeth ("trigger zones")
• Pain-free intervals between attacks
• No sensory/motor deficit (in idiopathic type)
• Affects middle-aged/elderly; more common in females
• Patient may grimace ("tic douloureux" = painful tic)

• Classical (idiopathic): Vascular compression of trigeminal nerve root (superior cerebellar artery most common)
• Symptomatic: Due to MS, tumor, AVM, brainstem lesion

• Atypical facial pain
• MPDS (myofascial pain dysfunction syndrome)
• Dental pain / pulpitis
• Glossopharyngeal neuralgia
• Post-herpetic neuralgia
• Cluster headache
• Migraine

1. Carbamazepine (drug of choice) - 200-1200 mg/day; sodium channel blocker; 70-80% success
2. Oxcarbazepine - better tolerated than carbamazepine
3. Baclofen - GABA-B agonist; adjunct
4. Gabapentin/Pregabalin
5. Phenytoin - less effective

1. Microvascular decompression (MVD / Jannetta procedure) - gold standard surgical treatment; posterior fossa craniotomy; Teflon pledget placed between nerve and offending vessel; high success rate, long-lasting
2. Percutaneous procedures (destructive):
   • Glycerol rhizolysis
   • Balloon microcompression
   • Radiofrequency thermocoagulation
3. Stereotactic radiosurgery (Gamma Knife) - non-invasive; radiation to nerve root
4. Peripheral neurectomy - avulsion of peripheral branches (infraorbital, mental nerve); temporary relief; neurectomy of V2 via infraorbital foramen
5. Alcohol nerve block - peripheral; temporary; historically used

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18. Dislocation of TMJ - Causes, Clinical Features & Treatment

• Excessive mouth opening (yawning, dental procedures, intubation)
• Trauma to the jaw
• Convulsive seizures
• Loss of posterior teeth (decreases vertical dimension)
• Ligamentous laxity
• Shallow articular eminence
• Habitual dislocation (recurrent)

• Inability to close mouth
• Anterior open bite
• Deviation of midline (unilateral) or bilateral symmetrical protrusion
• Palpable gap in preauricular region (empty glenoid fossa)
• Preauricular pain
• Pooling of saliva, difficulty speaking
• Spasm of masticatory muscles

• Acute/Chronic (habitual/recurrent)
• Unilateral/Bilateral
• Anterior (most common), Posterior, Lateral, Superior

1. Hippocratic method (manual reduction)
   • Thumbs placed on lower molars, fingers under the chin
   • Downward pressure on molars + upward pressure on chin to disengage condyle from eminence, then guide back into fossa
   • Sedation/muscle relaxant may be needed

1. Injection of sclerosing agents (autologous blood, sodium morrhuate) into joint
2. Eminectomy (Myrhaug procedure) - removal of articular eminence; allows condyle to freely move without entrapment
3. Eminoplasty / Augmentation - increases eminence height to block excessive condylar movement
4. Le Clerc's operation - sling of temporal fascia to restrict condylar movement
5. Dautrey's procedure - downfracture of zygomatic arch to act as a mechanical block
6. Arthroscopic procedures

• Open reduction under GA with or without condylotomy

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19. TMJ Ankylosis (Short Note)

• Most common cause: trauma, infection
• Hallmark: trismus (inability to open mouth)
• Investigation: OPG + CT
• Treatment: gap arthroplasty + interpositional material + aggressive physiotherapy
• Children: costochondral graft preferred

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20. Myofascial Pain Dysfunction Syndrome (MPDS)

1. Dull, aching, unilateral pain in the preauricular region
2. Tenderness on palpation of masticatory muscles (especially pterygoids)
3. TMJ clicking (clicking due to muscle incoordination)
4. Limited/deviated mouth opening
5. Absence of radiographic changes in TMJ
6. Absence of tenderness directly over the joint

• Dull, aching facial pain - worse in morning (nocturnal bruxism) or evening (daytime stress)
• Pain radiates to ear, temple, neck
• Clicking or popping sounds
• Limited mouth opening (25-35 mm range)
• Muscle tenderness on palpation
• Headache, earache
• No true joint pathology on imaging

1. Reassurance and explanation - most important
2. Rest - soft diet, avoid wide opening
3. Occlusal splint (Michigan/stabilization splint) - night guard to prevent bruxism
4. Physiotherapy - heat, ultrasound, TENS, jaw exercises
5. NSAIDs for acute pain
6. Muscle relaxants - diazepam, cyclobenzaprine
7. Stress management / counseling / biofeedback
8. Trigger point injections (local anesthetic ± corticosteroid)
9. Occlusal adjustment (rarely needed)
10. Botulinum toxin injection for refractory cases

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21. Tic Douloureux

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22. Subluxation

• Clicking sound (often loud) near end of mouth opening
• Jaw deviates and momentarily "catches" then self-corrects
• Usually asymptomatic; occasionally painful
• Associated with ligament laxity

• Reassurance (usually no treatment needed)
• If symptomatic: same as recurrent dislocation management
• Sclerosing injections, eminectomy for severe cases

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23. TMJ Dislocation

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24. Bell's Palsy

• Sudden onset unilateral facial weakness (develops over hours to days)
• LMN palsy features - ALL branches affected: forehead, eye, mouth
  • Cannot close eye (lagophthalmos)
  • Loss of forehead wrinkles
  • Drooping of mouth corner
  • Bell's phenomenon (eye rolls up when patient tries to close eye - protective reflex)
• Loss of taste (anterior 2/3 tongue) - if chorda tympani involved
• Hyperacusis - if nerve to stapedius involved
• Reduced lacrimation
• No sensory loss (facial sensation is trigeminal)

1. Oral corticosteroids (prednisolone 1 mg/kg/day for 10 days) - first-line; started within 72 hours
2. Antiviral (acyclovir/valacyclovir) - added to steroids (benefit unclear but commonly used)
3. Eye care - lubricating eye drops, taping eye at night (prevents corneal exposure)
4. Physiotherapy - facial exercises
5. Surgical decompression - rare; for complete paralysis with poor electrical function

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25. Kaban's Protocol

1. Aggressive resection of ankylotic mass (condylectomy + removal of medial and lateral bone)
2. Coronoidectomy on ipsilateral side
3. Coronoidectomy on contralateral side (if mouth opening < 35 mm after ipsilateral coronoidectomy)
4. Lining of the TMJ fossa with temporalis myofascial flap or alloplastic material
5. Reconstruction of the ramus-condyle unit with CCG (in children) or total joint prosthesis (adults)
6. Rigid fixation of the graft
7. Early mobilization and aggressive physiotherapy (within 3-5 days post-op) + long-term (6 months minimum)

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26. Frey Syndrome (Auriculotemporal Nerve Syndrome)

• Gustatory sweating (sweating while eating)
• Redness/flushing over the preauricular area during eating
• No pain

• Minor's starch-iodine test - iodine painted on skin, dusted with starch; area turns dark blue/purple during eating (sweat + iodine + starch reaction)

1. Reassurance (often mild and acceptable)
2. Botulinum toxin A injection - most effective; blocks sweating (repeat every 6-12 months)
3. Re-operation - interposition of barrier (temporalis fascia) between skin and parotid bed
4. Anticholinergic creams (scopolamine)
5. Tympanic neurectomy (Jacobson's nerve) - rarely done

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27. Etiology and Clinical Features of TMJ Ankylosis

1. Trauma (most common - condylar fractures in children)
2. Infection (otitis media, mastoiditis, septic arthritis)
3. Systemic disease (RA, ankylosing spondylitis, Still's disease)
4. Neonatal (forceps delivery injury)
5. Irradiation (rare)

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28. Bell's Sign [2M]

• When a patient with Bell's palsy (LMN facial palsy) attempts to close the eye, the eyeball involuntarily rolls upward and slightly outward, exposing the white sclera.
• This is a normal protective brainstem reflex (eye rolling upward) that becomes visible because the patient cannot close the eyelid (orbicularis oculi paralysis).
• It is a sign of LMN facial nerve palsy.
• Clinical significance: confirms LMN lesion; indicates risk of corneal exposure injury requiring eye protection.

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29. Arthrocentesis

• Closed lock (acute disc displacement without reduction)
• Inflammatory arthritis of TMJ
• Chronic pain unresponsive to conservative treatment
• Post-traumatic joint stiffness

1. Under LA (auriculotemporal nerve block); sometimes sedation
2. Two landmarks: tragus and outer canthus of eye; joint space located 10 mm anterior to tragus along canthotragal line
3. 18-gauge needle inserted into superior joint space (first needle - inflow)
4. Second 19-gauge needle placed 10 mm anterior to first (outflow)
5. 200-300 mL lactated Ringer's or saline irrigated through joint
6. Hydraulic distension of joint; lysis of adhesions
7. Optional: corticosteroid/hyaluronic acid injection at end

• Simple, office-based, minimal invasion
• No scarring
• Can be combined with injection of sodium hyaluronate

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30. CSF Rhinorrhea

• Traumatic (most common) - skull base fracture (anterior cranial fossa, cribriform plate)
• Surgical - post-sinus surgery, transsphenoidal surgery
• Spontaneous - elevated ICP (obesity, idiopathic intracranial hypertension)
• Tumor erosion

• Unilateral watery nasal discharge (clear, watery)
• "Halo sign" - blood-tinged CSF on filter paper shows clear halo around blood
• "Reservoir sign" (or "Bowing sign") - fluid increases when patient bends head down
• Salty/sweet taste
• May be associated with anosmia (cribriform plate injury), meningitis

• Beta-2 transferrin (β2-transferrin) - gold standard test; present in CSF but not normal nasal secretions
• Glucose in fluid (>30 mg/dL suggests CSF; unreliable)
• CT cisternography - localizes defect
• MRI cisternography
• Fluorescein intrathecal injection (for intraoperative localization)

• Meningitis (most serious - Streptococcus pneumoniae)
• Brain abscess

• Conservative (most traumatic cases heal within 2 weeks):
  • Bed rest, head elevation 30°
  • Avoid nose blowing, coughing
  • Stool softeners
  • Prophylactic antibiotics (controversial)
  • Acetazolamide (reduces CSF production)
  • Lumbar drain
• Surgical:
  • Endoscopic endonasal repair (most common - fascia lata/fat plug, mucosal flap)
  • Craniotomy repair (for large or failed endoscopic repair)

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31. Eminectomy

• Recurrent/habitual TMJ dislocation
• Subluxation with symptoms

1. Preauricular incision
2. Dissection to expose the articular eminence
3. Eminence reduced to a flat surface using burs (creating a flat path for condyle)
4. Wound closure

• Augmentation eminoplasty - builds up the eminence to increase its height (prevents condyle from sliding over)
• Dautrey's procedure - fractured zygomatic arch acts as a block
• Le Clerc's procedure - fascial sling restricts condyle

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32. Tinel Sign

• Assessment of inferior alveolar nerve (IAN) recovery after mandibular fracture, osteotomy, or implant-related nerve injury
• Carpal tunnel syndrome (tapping over carpal tunnel)
• Post-traumatic nerve injury assessment

• Tinel's sign advances distally as nerve regenerates (at 1 mm/day)
• Used to track recovery progress
• Persistent proximal Tinel's with no distal advance = poor prognosis for regeneration

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QUICK REFERENCE TABLE

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CYSTS & ORAL PATHOLOGY (Top Section)

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1. Enucleation & Marsupialization

Enucleation

• Small to medium cysts
• Cysts not closely related to vital structures (teeth, nerves, vessels)
• Dentigerous cysts, radicular cysts, lateral periodontal cysts
• Recurrence-prone cysts (OKC) - combined with Carnoy's solution

1. LA + mucoperiosteal flap raised
2. Bony window created over cyst
3. Cyst wall separated from bone using curved periosteal elevator (Mitchell's trimmer)
4. Entire sac removed intact
5. Bony cavity irrigated, edges smoothed
6. Primary closure (wound sutured)
7. Cavity fills with blood clot → organizes into bone

• Specimen available for histopathology
• Complete removal → lower recurrence
• Faster healing

• Risk to adjacent teeth/nerves
• Not suitable for large cysts (weakens jaw → fracture risk)

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Marsupialization (Partsch I Operation)

• Large cysts where enucleation risks jaw fracture or damage to vital structures
• Cysts extending to the maxillary sinus
• Dentigerous cysts in children (to allow tooth eruption)
• Elderly/medically compromised patients
• As preliminary step before enucleation (two-stage approach)

1. Window created in the most prominent/accessible part of the cyst
2. Cyst contents aspirated
3. Cyst wall trimmed
4. Cyst lining sutured to oral mucosa (creating open cavity)
5. Cavity packed with iodoform gauze or an obturator/plug fitted
6. Patient irrigates cavity regularly
7. Cavity gradually shrinks over months

• Simple, less invasive
• No risk to adjacent teeth/nerves
• Suitable for large cysts
• Allows unerupted teeth to erupt

• Long treatment time (months to years)
• Requires patient compliance for irrigation
• No complete specimen for histology
• Residual cyst may remain

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2. TNM Classification

• M0 = No distant metastasis
• M1 = Distant metastasis present

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3. Transillumination Test [2M]

1. Performed in a darkened room
2. Fiberoptic light or bright torch placed against the skin/mucosa overlying the swelling
3. Positive result: the entire swelling lights up ("glow") uniformly

• Cysts (maxillary sinus cysts, mucous retention cysts)
• Ranula
• Mucocele
• Sinus filled with fluid

• Solid tumors
• Hemangioma (partially)
• Bone lesions

• Differentiation of cystic vs. solid swelling
• Checking for fluid in maxillary antrum (sinusitis)
• Part of clinical examination of intraoral swellings

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4. Incision & Drainage (I&D)

• Fluctuant dental abscess
• Cellulitis progressing to abscess stage
• Space infections (submandibular, sublingual, parapharyngeal, etc.)
• Ludwig's angina (early I&D to decompress multiple spaces)

• Fluctuation (pus present = abscess stage; cellulitis should NOT be incised)
• Appropriate LA (NEVER inject directly into infected tissue - ineffective and spreads infection; use field block or regional nerve block)

1. Regional/field block anesthesia
2. Stab incision at the most dependent/fluctuant point (allows gravity drainage)
3. Incision carried to depth of abscess with artery forceps (blunt dissection - avoids neurovascular structures)
4. Pus evacuated; irrigated with saline
5. Corrugated rubber drain / Penrose drain inserted and sutured in place
6. Drain maintained for 24-48 hours or until drainage ceases
7. Antibiotics, analgesics, warm saline rinses

• Intraoral preferred when abscess points intraorally (less scarring)
• Extraoral needed for deep space infections, Ludwig's angina, parapharyngeal/parotid abscesses

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5. Theories of Cyst Expansion

1. Osmotic/Hydrostatic Pressure Theory (Toller)

• Cyst fluid has higher osmotic pressure than serum (due to desquamated cells, proteins, Na+)
• Water is drawn into the cyst by osmosis → intracystic pressure increases → cyst expands
• Most widely accepted classic theory

2. Bone Resorbing Factors Theory

• Prostaglandins (PGE1, PGE2), interleukins (IL-1, IL-6), collagenase, hyaluronidase released by cyst epithelium
• These factors activate osteoclasts → peripheral bone resorption
• Particularly relevant for OKC which lacks osmotic mechanism

3. Epithelial Proliferation Theory

• Continued proliferation of the cyst lining epithelium exerts pressure from within
• The enlarging epithelium physically pushes against bone

4. Mural Growth Theory (important for OKC)

• Satellite cysts and epithelial islands in the cyst wall proliferate
• OKC expands more in an anteroposterior direction (along medullary canal) rather than expanding bone
• OKC does NOT depend on osmotic pressure for expansion (cyst fluid osmolarity is similar to plasma)

5. Enzymatic Theory

• Collagenase and other enzymes secreted by the cyst lining
• Dissolve the surrounding bone collagen matrix

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6. Complex Odontoma

• Asymptomatic, discovered on routine X-ray
• Associated with unerupted tooth (most common cause of unerupted lower 2nd molar)
• Slow growing
• Rare swelling or expansion

• Dense, irregular, amorphous radiopaque mass
• Surrounded by thin radiolucent zone (capsule)
• Associated with unerupted tooth

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7. Ranula

1. Simple/Superficial ranula - confined to floor of mouth above mylohyoid muscle; fluctuant, bluish, translucent swelling
2. Plunging/Cervical ranula - mucus herniates through mylohyoid muscle → presents as cervical swelling (may not have floor of mouth component)

• Fluctuant, bluish, translucent swelling in floor of mouth
• Usually unilateral
• Asymptomatic unless large
• May interfere with speech, swallowing
• Transillumination: positive (fluid-filled)
• "Frog belly" appearance (ranula = little frog in Latin)

1. Marsupialization - preferred for simple ranula; window created in roof of cyst; allows drainage and prevents recurrence
2. Excision with sublingual gland removal - most definitive; removes source of mucus; prevents recurrence
3. Enucleation alone - high recurrence
4. For plunging ranula: Intraoral excision of sublingual gland (removes source); cervical approach if large

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8. Keratocyst (Odontogenic Keratocyst / OKC)

• Most common in mandible (75%), especially in ramus/3rd molar area
• 2nd-4th decade; male predominance
• Often asymptomatic until large
• Expands in anteroposterior direction (along medullary canal) - minimal buccal/lingual expansion
• Can be associated with unerupted teeth
• When multiple OKCs + bifid ribs + calcified falx cerebri + basal cell nevi → Gorlin-Goltz syndrome (Nevoid basal cell carcinoma syndrome)

• Unilocular or multilocular radiolucency with scalloped, well-corticated borders
• Does NOT cause expansion (unlike other cysts)
• May cause root resorption (less common than expected)

• Thin uniform epithelial lining (6-8 cell layers)
• Parakeratinized surface (corrugated/wavy)
• Flat epithelial-connective tissue interface (no rete ridges)
• Palisaded basal cell layer with reverse nuclear polarity (nuclei away from basement membrane)
• Satellite cysts and epithelial islands in fibrous wall
• Thin fibrous capsule (prone to tearing)

• Aggressive - expands along bone
• High recurrence rate (25-60%) - due to satellite cysts, thin friable lining, daughter cysts
• Potential for malignant transformation (rare, <1%)

• Enucleation + Carnoy's solution fixation (destroys satellite cysts in bone)
• Marsupialization followed by enucleation (two-stage)

• Peripheral ostectomy (removal of 1-2 mm of bone surrounding cyst)
• Resection (for recurrent/Gorlin-Goltz cases)

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9. Waldron's Procedure

• Large cysts cannot be enucleated directly without risk of jaw fracture or damage to vital structures
• Marsupialization first decompresses the cyst, allows bone to partially fill in, and reduces cyst size
• After several months, the now-smaller cyst can be safely enucleated

1. Stage 1 (Partsch I - Marsupialization):
   • Window created; cyst contents evacuated
   • Cyst lining sutured to oral mucosa
   • Obturator fabricated; patient irrigates daily
   • Continued for several months until cyst shrinks significantly
2. Stage 2 (Enucleation):
   • Once cyst is reduced in size
   • Complete enucleation performed
   • Histopathology of the remaining lining

• Preserves vital structures (IAN, teeth)
• Prevents pathological fracture
• Allows eruption of associated teeth

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TRAUMA, DENTOFACIAL DEFORMITIES

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10. Classify Mandibular Condylar Fractures. Clinical Features, Radiographic Evaluation & Management Techniques

Classification of Condylar Fractures:

1. Condylar head (intracapsular/diacapitular) - fracture within the joint capsule
2. Condylar neck - just below the condylar head
3. Subcondylar (subchondral) - at the level of the sigmoid notch

• Type I: No displacement (undisplaced)
• Type II: Slight displacement
• Type III: Displacement with overlap but articular surface intact
• Type IV: Condyle displaced out of fossa anteriorly/medially
• Type V: Vertical fracture through condylar head
• Type VI: Fracture at condylar neck with dislocation out of fossa

• 0 = No displacement
• 1 = Deviation only
• 2 = Slight displacement
• 3 = Gross displacement (contact between fragments present)
• 4 = No contact between fragments (complete dislocation)

Clinical Features:

• Pain and swelling in preauricular region
• Limited/painful mouth opening (trismus)
• Unilateral condylar fracture: Mandible deviates to fractured side on opening (pterygoid muscle unopposed on normal side pulls jaw away from fracture); anterior open bite on opposite side
• Bilateral condylar fracture: Bilateral preauricular pain; anterior open bite (both condyles displaced, mandible rotates); class III appearance; "Dish face" deformity if associated with symphysis fracture
• Gagging of posterior teeth on affected side
• Ecchymosis, hematoma in preauricular area
• Step deformity in ramus

Radiographic Evaluation:

1. OPG (Orthopantomogram) - first-line; shows condyle position, fracture line, displacement
2. PA (Posteroanterior) skull view - shows medial/lateral displacement
3. Submentovertex view - medial condylar displacement
4. Reverse Towne's view - best plain film for condylar neck fractures
5. CT scan (3D CT) - gold standard; shows exact fracture pattern, displacement, dislocation
6. MRI - for intracapsular fractures, articular disc assessment

Management:

• Indications: Minimally displaced, intracapsular fractures in children, elderly/medically compromised, bilateral condylar fractures (relative)
• Method: IMF (intermaxillary fixation) with arch bars + elastic bands for 2-4 weeks → followed by aggressive physiotherapy
• IMF for children: 2-3 weeks only (avoid ankylosis)
• Functional therapy: early mobilization preferred for children

• Indications: (see below in Question 29)
• Approaches: Preauricular, retromandibular (transparotid), submandibular, endoscopic
• Fixation: Miniplates + monocortical screws

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11. Classification & Clinical Features of Middle Third Facial Skeleton Fractures. Management of Zygomatic Complex Fracture

Classification of Middle Third Facial Fractures:

• Le Fort I (Guerin's fracture / Floating palate): Horizontal fracture above the tooth apices; palate + teeth separated from upper facial skeleton; passes through nasal septum, lateral walls of nose, pterygoid plates
• Le Fort II (Pyramidal fracture): Pyramidal-shaped fracture; involves nasal bridge, lacrimal bones, orbital floor, lateral antral walls, pterygoid plates; "mobile" central face
• Le Fort III (Craniofacial disjunction): Complete separation of face from cranial base; passes through frontozygomatic suture, orbital walls, zygomatic arch, nasal bridge, pterygoid plates; entire face moves as one piece

• Zygomatic complex (ZMC) fracture
• Isolated zygomatic arch fracture
• Naso-orbito-ethmoid (NOE) fracture
• Orbital blow-out fracture
• Nasal fracture

Zygomatic Complex (ZMC) Fracture:

• Flattening of the cheek (malar eminence flattening)
• Step deformity at infraorbital rim and frontozygomatic suture
• Periorbital ecchymosis and edema ("panda eyes")
• Subconjunctival hemorrhage
• Diplopia (double vision) - due to orbital floor fracture, entrapment of inferior rectus
• Enophthalmos (sunken eye) - due to increased orbital volume
• Hypoesthesia/paresthesia of cheek, upper lip, teeth - infraorbital nerve injury
• Trismus - depressed arch impinging on coronoid process
• Epistaxis
• Lateral canthal displacement
• Antimongoloid slant of palpebral fissure

• OM view (Waters' view) - standard; shows ZMC fractures clearly, orbital floor, maxillary sinus opacity
• Submentovertex (jug-handle) view - zygomatic arch fractures
• CT face - definitive (3D reconstruction)

• Displaced fracture with cosmetic deformity
• Diplopia (entrapment of orbital contents)
• Enophthalmos
• Trismus (coronoid impingement)
• Infraorbital nerve deficit

1. Gillies temporal approach - temporal incision; periosteal elevator passed deep to temporalis fascia and superficial to arch; lever the arch out
2. Dingman's approach - hook through skin stab incision under the arch
3. Keen's approach - intraoral elevator through upper buccal sulcus; elevates the malar
4. Strohmeyer approach - direct approach over zygomatic arch

• 1-point fixation: at frontozygomatic suture (if other areas stable)
• 2-point fixation: frontozygomatic + infraorbital rim
• 3-point fixation: frontozygomatic + infraorbital rim + zygomaticomaxillary buttress
• 4-point: all 4 sutures

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12. Classify Mandibular Fractures. Clinical Features of Angle Fracture & Its Management

Classification of Mandibular Fractures:

1. Symphysis - between the two mental foramina (central incisor area)
2. Parasymphysis - from canine to mental foramen
3. Body - from mental foramen to angle
4. Angle - from the 3rd molar area posterior to masseter
5. Ramus - between angle and sigmoid notch
6. Subcondylar/Condylar neck
7. Condylar head
8. Coronoid process
9. Alveolar process
10. Dentoalveolar

• Simple (closed) - skin intact
• Compound (open) - communicates with exterior (most mandible fractures are compound via tooth socket or mucosa)
• Comminuted - multiple fragments
• Greenstick - incomplete; children
• Pathological - through diseased bone
• Multiple - two or more separate fractures

• Favorable - muscle pull reduces/maintains reduction
• Unfavorable - muscle pull displaces fragments

• Pain and swelling at the angle of the mandible
• Trismus (masseter, medial pterygoid insertion)
• Malocclusion - premature contact on affected side; open bite on contralateral side
• Deviation of mandible toward fractured side on opening
• Step deformity at the lower border (palpable extraorally)
• Mucosal laceration/bruising near the 3rd molar
• Paresthesia of lower lip (inferior alveolar nerve involvement rare but possible)
• Limited mouth opening
• Hemorrhage

• Arch bars (Erich arch bars) placed on upper and lower teeth
• IMF (intermaxillary fixation) for 6-8 weeks with wire or elastics
• Soft diet; strict oral hygiene

• Indicated for unfavorable, displaced, comminuted fractures
• Approach: intraoral (buccal sulcus incision) ± extraoral (submandibular incision)
• Fixation with titanium miniplates along Champy's lines of osteosynthesis:
  • One plate along external oblique ridge (tension band at superior border)
  • Champy's principle: angle fracture = 1 plate at superior border (external oblique) using monocortical screws

• Infection (3rd molar in fracture line may need extraction)
• Malunion, non-union
• Trismus
• IAN injury
• Temporomandibular joint complications

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13. Signs & Symptoms of Le Fort I Fracture & Management

• Anterior nasal spine
• Piriform aperture (above the floor of nose)
• Lateral nasal walls
• Posterior nasal septum
• Pterygoid plates (lower third)

• "Floating palate" - mobile maxilla; grasping and rocking the anterior teeth causes the palate to move but not the rest of the face
• Malocclusion - class III, anterior open bite, or gagging of posterior teeth
• Facial swelling and edema around nose/upper lip
• Submucosal hemorrhage in upper buccal sulcus
• Step deformity at the piriform rim / anterior nasal spine area
• Epistaxis
• Mucosal lacerations in upper buccal vestibule
• Guerin's sign: Ecchymosis in the soft palate (pathognomonic of Le Fort fracture)
• Nasal deviation or septal injury
• Dish face deformity (impacted fracture) or elongated face (disimpacted)

1. Primary: Airway, hemorrhage control, ABC
2. Reduction: Walsham's forceps for nasal reduction; Rowe's disimpaction forceps to disimpact maxilla
3. IMF: With arch bars or eyelet wires; establish pre-injury occlusion
4. Internal fixation:
   • Two plates at zygomaticomaxillary (ZM) buttresses (right and left)
   • Often combined with piriform rim plates
5. Bone grafting if severely comminuted

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14. Define Fracture. Classify Mandibular Fractures. Note on Treatment of Condylar Fracture

• Undisplaced: Soft diet, analgesics, follow-up
• Displaced (intracapsular/condylar head): IMF 2-3 weeks; then aggressive mobilization
• Used in: Children (avoid growth disturbance), unilateral low condylar fractures, elderly/compromised

• Approaches: Preauricular, retromandibular transparotid (Hinds), Hinds-Girard, submandibular, endoscopic
• Fixation: Miniplates (2-plate technique for condylar neck) with monocortical screws
• Indications for open: see Question 29

• Early IMF release (3 weeks) + functional appliances
• Prevents ankylosis and growth disturbance

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15. Bilateral Condylar Fractures - Clinical Features, Diagnosis & Management

• Bilateral preauricular pain, swelling, trismus
• Anterior open bite (both condyles displaced superiorly; rami shorten; mandible drops anteriorly)
• Class III tendency (mandible appears prognathic)
• Bilateral deviation on mouth opening - or may open symmetrically
• Gagging of posterior teeth (both sides)
• Tenderness on bilateral condyle palpation
• Bilateral ecchymosis preauricular area
• "Flat face" deformity

• Clinical + OPG (shows both condyles)
• PA skull, Reverse Towne's, Submentovertex views
• CT face (gold standard)

• IMF to establish occlusion (arch bars bilaterally)
• Open reduction of at least one side (if significantly displaced)
• For bilateral displaced: May reduce open bilaterally, or open one and closed the other depending on severity
• In children: Closed management strongly preferred (ankylosis risk if opened); aggressive physiotherapy after short IMF
• Postoperative: Jaw exercises, occlusal monitoring

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16. Timing of Repair of Cleft Lip & Palate

• Child should be 10 weeks old
• Weighing at least 10 pounds (4.5 kg)
• Hemoglobin ≥ 10 g/dL
• WBC count ≤ 10,000/mm³

• Timing: 3 months (10-12 weeks) of age
• Rationale: By 3 months, child can tolerate general anesthesia, tissues are larger and easier to work with, yet surgery is early enough for good cosmetic results and speech development
• Common techniques: Millard's rotation-advancement technique (most popular), Tennison-Randall (geometric/Z-plasty), Le Mesurier

• Timing: 9-18 months (ideally before speech development begins)
• Earlier (9-12 months): Better speech outcomes (velopharygneal mechanism develops); more commonly practiced today
• Later repair (18 months - 2 years): Less disturbance to midface growth but compromises speech
• Common techniques: Von Langenbeck technique, Veau-Wardill-Kilner (V-Y pushback), Furlow double-opposing Z-plasty (best velopharyngeal function)

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17. Complications of Fracture

Immediate (at time of injury):

• Hemorrhage (external or internal)
• Shock
• Neurological injury (nerve damage, brain injury with skull fractures)
• Airway obstruction (tongue falls back in bilateral parasymphysis fractures, foreign bodies)
• Aspiration of blood/teeth/dentures

Early (days to weeks):

• Infection (especially compound fractures, 3rd molar in fracture line)
• Wound dehiscence
• Malunion - healing in incorrect position
• Trismus
• Hemorrhage (secondary)
• Nerve injury (IAN paresthesia)
• Pressure sores from IMF wires

Late (weeks to months):

• Non-union (fibrous or failed union; no bony bridging)
• Malunion (bony union in faulty position → malocclusion, cosmetic defect)
• Osteomyelitis (chronic infection)
• Ankylosis (especially condylar fractures in children)
• Condylar resorption
• Growth disturbance in children
• Eburnation (avascular necrosis → sclerotic bone)
• Salivary fistula
• Persistent paresthesia (nerve injury)
• Relapse of fracture

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18. Anterior Maxillary Osteotomy (AMO)

1. Wassmund technique - no mobilization of the premaxillary segment with the palate; tunneling approach
2. Wunderer technique - palatal approach; used for downward repositioning
3. Cupar technique
4. Epker technique - most commonly used today (modification of Wassmund/Wunderer)

• Maxillary anterior protrusion (dentoalveolar protrusion)
• Anterior open bite
• Deep bite correction
• Correction of Angle's Class II dental relationships (when full Le Fort I not needed)

1. Bilateral premolar extractions (usually 1st premolars)
2. Buccal cortical cuts from piriform rim to extraction site
3. Palatal cut posterior to anterior segment
4. Segment mobilized
5. Repositioned anteriorly/posteriorly/superiorly as planned
6. Fixed with miniplates

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19. Principles of Management of Facial Fractures

1. Life-threatening emergencies first: Airway (intubation/tracheostomy if needed), hemorrhage control, shock treatment (ATLS protocol)
2. Accurate diagnosis: Clinical examination + appropriate imaging (OPG, CT face)
3. Soft tissue management: Early suturing of lacerations; prevents scarring
4. Timing: Ideally within first few hours (before severe edema) or delayed (7-10 days after edema subsides); not during peak edema phase (days 2-5) unless life-threatening
5. Restore pre-injury occlusion: Using IMF as reference; dental occlusion guides fracture reduction
6. Fracture reduction: Exact anatomical repositioning
7. Stabilization/fixation: Adequate rigid fixation (miniplates, reconstruction plates, IMF)
8. Bone grafting where needed (comminuted/avulsed bone)
9. Soft tissue closure: Tension-free; layered
10. Postoperative care: Antibiotics, analgesics, physiotherapy, dietary instructions (soft diet), follow-up

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20. Indications for Open Reduction of Condylar Fractures

Absolute Indications:

1. Displacement of condyle into middle cranial fossa
2. Condyle displaced outside articular fossa with obstruction to jaw movement
3. Foreign body in joint
4. Bilateral condylar fractures with associated midface fractures requiring open fixation
5. Inability to achieve satisfactory occlusion with closed treatment

Relative Indications (favoring ORIF):

1. Condylar dislocation with displacement > 45° medially
2. Ramus height shortening > 4 mm
3. Fractures in adults (especially subcondylar level) where closed treatment may lead to malunion
4. Bilateral fractures with anterior open bite in adults
5. Patients unable to participate in physiotherapy (physically/mentally handicapped)
6. Condylar fractures in patients with multiple mandibular fractures
7. Patient requiring early function (musicians playing wind instruments, singers)

Contraindications to open:

• Intracapsular (condylar head) fractures
• Children (growth center - risk of ankylosis)
• Mild/undisplaced fractures

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21. Clinical Features of Le Fort III Fracture

• Nasofrontal suture
• Medial orbital wall (lacrimal bones)
• Floor of orbit
• Lateral orbital wall
• Frontozygomatic suture
• Zygomatic arch (bilaterally)
• Pterygoid plates (high)

• "Dish face" deformity (entire face looks flattened and retruded)
• Bilateral periorbital ecchymosis ("raccoon eyes" / "panda eyes")
• Bilateral subconjunctival hemorrhage
• Bilateral cerebrospinal fluid rhinorrhea (cribriform plate involvement)
• Elongated face (if fracture is impacted, shortened; if disimpacted, elongated)
• Profound malocclusion - class III, anterior open bite
• Entire midface mobile - grasping teeth moves the zygoma, nose, orbits as one unit
• Epistaxis
• Bilateral sensory deficit (infraorbital nerve)
• CSF rhinorrhea (most dangerous complication)
• Enophthalmos, diplopia (bilateral)
• Signs of intracranial injury

• Neurosurgical evaluation first
• Delay fixation if brain injury (until stable)
• Rowe's disimpaction forceps + IMF
• Le Fort III plate fixation: frontozygomatic sutures bilaterally, zygomatic arches, nasofrontal region
• Calvarial bone grafts if comminuted

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22. Le Fort II Fracture (Pyramidal Fracture)

• Nasofrontal suture
• Medial orbital wall and lacrimal bones
• Infraorbital rim (inferior orbital floor)
• Anterior wall of maxillary sinus
• Pterygoid plates (mid-level)

• "Pyramid" shaped mobile segment (nose + teeth + palate + anterior maxilla)
• Bilateral periorbital ecchymosis
• Bilateral subconjunctival hemorrhage
• Bilateral infraorbital paresthesia
• Step deformity at infraorbital rim and nasal bridge
• Swelling (mid face, nose)
• Epistaxis
• Malocclusion (anterior open bite, class III)
• Mobile middle face (nasal bones + premaxilla) - grasping incisor teeth rocks the central face; zygomatic bones do NOT move (distinguishes from Le Fort III)
• CSF rhinorrhea (less common than Le Fort III but possible)
• Enophthalmos, diplopia (orbital floor involvement)

• Rowe's disimpaction forceps for reduction
• IMF to establish occlusion
• Fixation: infraorbital rim plates, zygomaticomaxillary buttress plates, nasofrontal region
• Orbital floor reconstruction if needed

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23. Arch Bars

• IMF for jaw fractures
• Orthognathic surgery
• Dento-alveolar fractures
• Condylar fractures (closed treatment)
• Any situation requiring fixation of jaws in occlusion

1. The arch bar is contoured to the dental arch
2. Soft stainless steel wire (0.4 mm / 26-gauge) is passed under the contact points and twisted around the bar and teeth (circumdental wiring)
3. Applied to at least 3-4 teeth on each side of the fracture
4. Once both upper and lower arch bars are placed, elastic bands or wires are attached to the hooks of upper and lower arch bars to achieve IMF

• Ivy eyelet wiring: Wire loops placed around pairs of teeth; elastic/wire bands connect upper and lower loops
• Gilmer wiring: Simplest; single wire looped around upper and lower teeth together
• Ernst wiring: Wire passed through dental interdental spaces to create loops for IMF
• Cap splints (acrylic): Used for edentulous fractures

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24. Classify Middle Third Facial Fractures

1. Le Fort I - horizontal/Guerin's/floating palate
2. Le Fort II - pyramidal fracture
3. Le Fort III - craniofacial disjunction
4. Zygomatic complex fracture (tetrapod fracture)
5. Zygomatic arch fracture (isolated)
6. Naso-orbito-ethmoid (NOE) fracture
7. Orbital blow-out fracture (pure and impure)
8. Nasal fracture
9. Alveolar fracture

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25. Bilateral Sagittal Split Osteotomy (BSSO)

• Mandibular retrognathia (advancement)
• Mandibular prognathia (setback)
• Facial asymmetry
• Anterior open bite (autorotation + BSSO)
• Combined with Le Fort I as bimaxillary surgery

1. Horizontal cut - on medial ramus above the lingula (horizontal medial cut through inner cortex only)
2. Vertical cut - on lateral ramus/body below and parallel to external oblique ridge (buccal cortex)
3. Sagittal cut - connecting the two along the external oblique ridge (through cancellous bone)

• Bicortical screws (positional / lag screws) - most common; 3 screws placed transbuccally
• Miniplates (monocortical)

• IAN paresthesia (most common; 70-80% transient; 10% permanent)
• Bad split (unfavorable fracture of segment)
• Condylar sag / torque
• Relapse
• Infection, non-union

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ADDITIONAL TOPICS (Lower Section)

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26. Distraction Osteogenesis

1. Latency period (7-10 days post-osteotomy) - soft callus forms across the osteotomy
2. Activation/Distraction phase - device activated; bone segments separated at 1 mm/day (0.5 mm twice daily)
3. Consolidation phase - device left in place; new bone mineralizes; 6-8 weeks (2x distraction time)
4. Remodeling phase - device removed; bone continues to mature

• Mandibular lengthening (micrognathia, hemifacial microsomia)
• TMJ ankylosis (distraction to lengthen the ramus)
• Midface advancement (Le Fort III level distraction)
• Alveolar distraction (vertical ridge augmentation before implants)
• Cleft palate patients

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27. Pyramidal Fracture [2M]

• Mobile central face (nose + premaxilla + palate)
• Zygomatic bones NOT involved (distinguishes from Le Fort III)
• Step at nasofrontal and infraorbital areas
• Bilateral infraorbital paresthesia

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28. Define Orthognathic Surgery

• Correct skeletal jaw discrepancies
• Achieve ideal dental occlusion
• Improve facial aesthetics
• Improve function (mastication, speech, breathing)

• Clinical photographs, dental models, cephalometric analysis (lateral cephalogram)
• Model surgery (articulator-mounted casts)
• Surgical wafers (occlusal wafers)
• Virtual surgical planning (VSP) - modern approach using 3D CT data

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29. Classification of Maxillary Orthognathic Procedures

1. Le Fort I osteotomy - entire maxilla repositioned (up/down/forward/back/rotated); workhorse of maxillary surgery
2. Le Fort II osteotomy - central segment of midface (rarely used clinically)
3. Le Fort III osteotomy - craniofacial disjunction; total midface advancement
4. Anterior maxillary osteotomy (AMO) - anterior segment only (Wassmund/Wunderer)
5. Posterior maxillary osteotomy - posterior segment; for bite correction
6. Total subapical osteotomy - all teeth-bearing maxilla below apices
7. Palatal osteotomy - splitting of palate for expansion
8. Surgically assisted rapid palatal expansion (SARPE) - Le Fort I level cuts + midpalatal split + expansion device

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30. Classification of Mandibular Orthognathic Procedures

1. Bilateral Sagittal Split Osteotomy (BSSO) - Trauner-Obwegeser; advancement or setback; most versatile
2. Vertical ramus osteotomy (VRO) / Intraoral vertical ramus osteotomy (IVRO) - mandibular setback; no nerve at risk; no rigid fixation needed; IMF 6 weeks
3. Oblique subcondylar osteotomy
4. C-osteotomy
5. Inverted-L osteotomy

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31. Dental Wiring Techniques

1. Gilmer wiring - simplest; wire passed around adjacent upper and lower teeth and twisted; no loops
2. Ivy eyelet wiring - twisted wire eyelet placed between pairs of teeth; most popular for quick IMF
3. Ernst wiring - complex looped wire technique; strong
4. Stout's multiple loop wiring - multiple loops for difficult dentitions
5. Arch bars (Erich arch bar) - described above in Question 23
6. Continuous loop wiring - wire looped around multiple teeth; then upper/lower connected
7. Box wiring - wire forms a box around two opposing pairs of teeth

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32. Types of Blow-out Fracture

1. Pure blow-out fracture:
   • Orbital rim intact
   • Only internal orbital walls fractured (floor and/or medial wall)
   • Floor blow-out (most common): Contents herniate into maxillary sinus
   • Medial wall blow-out: Contents herniate into ethmoid sinuses
2. Impure blow-out fracture:
   • Orbital rim fractured in addition to internal walls
   • Associated with ZMC or Le Fort fractures
3. Blow-in fracture: (rare)
   • Direct blow causes orbital wall to cave inward (into the orbit)
   • Reduces orbital volume → enophthalmos
   • Opposite mechanism to blow-out

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33. Orbital Blow-out Fracture

1. Hydraulic theory (most accepted): Direct blow to globe → sudden pressure rise in orbit → weakest wall (floor/medial) fractures outward
2. Buckling theory: Force transmitted via orbital rim → buckling of thin floor before rim fractures

• Diplopia (double vision) - entrapment of inferior rectus/oblique in fracture gap → restricted upgaze most common
• Enophthalmos (sunken eye) - orbital fat herniates into sinus; increased orbital volume
• Infraorbital hypoesthesia - infraorbital nerve in floor
• Periorbital edema and ecchymosis
• Limitation of upward gaze (inferior rectus entrapment)
• Subcutaneous emphysema (air from sinus enters orbital tissues when patient blows nose - advise not to blow nose)
• Negative forced duction test (in true entrapment)
• Palpable step deformity (impure fractures)

• Waters' view: "Teardrop sign" - soft tissue mass hanging into maxillary sinus; sinus opacity
• CT orbits: fracture of orbital floor, herniated fat/muscle, entrapment
• "Trapdoor fracture" (in children): incomplete greenstick fracture; muscle traps through small defect; severe restriction; requires urgent surgery

1. Persistent diplopia (with positive forced duction - confirmed entrapment)
2. Enophthalmos > 2 mm (cosmetically significant)
3. Large floor defect (>50% of floor)
4. "Trapdoor" fracture (urgent in children - muscle ischemia)

• Transconjunctival or subciliary approach to orbital floor
• Herniated contents reduced
• Floor reconstructed with: titanium mesh, porous polyethylene (Medpor), silastic sheet, autogenous bone (calvarial/iliac)

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34. Indications of Surgical Management of Condyle Fracture

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35. Champy's Lines of Osteosynthesis

• The mandible is subject to complex forces during function: tension at the superior border (alveolar region) and compression at the inferior border
• Plates should be placed along the tension band (superior border) to neutralize these forces
• Monocortical screws sufficient as they avoid the IAN

• No IMF needed (or minimal)
• Preserves IAN (monocortical screws stay buccal)
• Early mobilization
• Functional use of mandible
• Lower infection rate than transosseous wires

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36. Visor Osteotomy

• Atrophic mandibular ridge (knife-edge ridge)
• Pre-implant surgery to widen the ridge
• Combined with bone grafting

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37. Guerin's Sign

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38. Battle's Sign

• Hemotympanum (blood behind the eardrum)
• Conductive or sensorineural hearing loss
• Facial nerve palsy (if fracture crosses the nerve canal)
• CSF otorrhea

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39. Coleman's Sign

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40. Malunion

• Inadequate reduction
• Inadequate fixation (mobile plates/wires)
• Non-compliance with IMF
• Loss of fixation during healing
• Unrecognized fracture

• Malocclusion (facial fracture malunion)
• Facial asymmetry or deformity
• Restricted jaw movement
• Cosmetic deformity (sunken cheek, dish face)

• Refracture and re-reduction (if early, within 6 weeks - bone still soft)
• Corrective osteotomy (if established malunion): Le Fort I, BSSO, genioplasty as indicated
• Bone contouring/recontouring

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41. Non-union

• Infection (osteomyelitis) - most common in mandible
• Inadequate immobilization
• Poor bone contact
• Severely comminuted fractures
• Compromised blood supply (soft tissue stripping, radiation)
• Systemic conditions (diabetes, osteoporosis, malnutrition, steroids)
• Pathological fracture (through tumor/cyst)

• No bony bridging across fracture site
• Sclerotic (dense) bone ends (eburnated)
• Fracture gap persists

• Persistent mobility at fracture site after expected healing time
• Pain on movement
• Malocclusion
• May have draining sinus (if infected)

1. Treat infection first (antibiotics, debridement, sequestrectomy)
2. Rigid stabilization - reconstruction plate (load-bearing plate) across non-union site
3. Bone grafting - autogenous (iliac crest, rib) to fill the gap and stimulate osteogenesis
4. May require removal of sclerotic bone ends + freshening
5. Systemic optimization (diabetic control, nutrition)

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42. Eburnation

• When a fracture non-union persists, the bone ends become sclerotic, dense (eburnated) due to avascular changes and reactive bone formation
• Seen radiographically as dense sclerotic margins at non-union site

• In severe degenerative joint disease: articular cartilage eroded → subchondral bone exposed → polished, dense ("eburnated") bone surface
• Can be seen in severe condylar resorption

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43. Rigid Internal Fixation (RIF)

1. Reconstruction plates (load-bearing): 2.4-2.7 mm systems; for comminuted fractures, non-unions; plate bears all functional load
2. Miniplates (load-sharing): 2.0 mm Champy system; most common for mandible fractures; monocortical screws; bone shares the load
3. Microplates: 1.0-1.5 mm; midface, zygomatic arch
4. Lag screws: Compression across fracture site
5. Positional screws: For BSSO

• No IMF needed (or short-term IMF)
• Early jaw mobilization and function
• Faster rehabilitation
• Lower infection rate
• Better nutrition (patient can eat sooner)
• Avoids complications of prolonged IMF (joint stiffness, periodontal disease, muscle atrophy, airway risk)

• Second surgery for plate removal (optional with titanium)
• Infection risk (foreign body)
• Nerve damage (IAN with bicortical screws)
• Stress shielding

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QUICK REFERENCE TABLE