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TRAUMA & DENTOFACIAL DEFORMITIES - Comprehensive Answers

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1. Classify Mandibular Condylar Fractures. Describe Clinical Features, Radiographic Evaluation & Management

Classification (Spiessl's Classification)

• Type I: Subcondylar fracture - no displacement
• Type II: Subcondylar fracture - with displacement (without dislocation)
• Type III: Subcondylar fracture - with dislocation from glenoid fossa
• Type IV: Dislocation of condylar head anteriorly
• Type V: Vertical/oblique osteochondral fracture
• Type VI: Intracapsular fracture (condylar head fracture)

• Condylar head (intracapsular/diacapitular)
• Condylar neck (subcondylar)
• Subcondylar (base of condyle)

• Nondisplaced
• Displaced (medial, lateral, anterior)
• Dislocated (condyle outside glenoid fossa)

Clinical Features

• Pain and tenderness in preauricular region
• Deviation of mandible to the affected side on opening (due to loss of condylar translation)
• Anterior open bite (bilateral fractures - both condyles displaced inferiorly, elongating rami; premature contact on posterior teeth)
• Limitation of mouth opening (trismus)
• Malocclusion - premature posterior contact, cross-bite
• Ecchymosis/hematoma in preauricular area
• Hemarthrosis (swelling in front of tragus)
• Bleeding from ear (if accompanied by tympanic plate fracture)
• Unilateral: chin deviates to fractured side

Radiographic Evaluation

• OPG (Orthopantomogram): First line - shows condyle position, fracture line, displacement
• PA mandible: Mediolateral displacement
• Lateral oblique view: AP displacement
• TMJ view (Towne's projection): Intracapsular fractures
• CT scan (gold standard): 3D reconstruction, exact displacement, angulation, dislocation
• Cone Beam CT (CBCT): Precise 3D imaging with less radiation

Management

• Indications: Nondisplaced/minimally displaced fractures, children (risk of ankylosis with surgery), elderly/medically compromised patients
• IMF (Intermaxillary Fixation): 2-4 weeks with arch bars/Erich arch bars, followed by physiotherapy
• Functional therapy: Early mobilization, physiotherapy

• Indications:
  • Displacement >30°
  • Shortening of ramus height >5mm
  • Bilateral fractures with severe malocclusion
  • Condyle dislocated into middle cranial fossa or external auditory canal
  • Failed closed treatment
  • Associated with other fractures requiring ORIF
• Approaches: Preauricular, retromandibular, submandibular, endoscopic
• Fixation: Miniplates (2 plates in an "X" pattern), lag screws

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

Classification of Middle Third Fractures

• Le Fort I (Guerin's fracture / transverse fracture): Horizontal fracture separating alveolar process from rest of maxilla. Fracture runs through: pyriform aperture, lateral walls of nasal fossa, lower maxillary sinus, pterygoid plates (lower third)
• Le Fort II (Pyramidal fracture): Pyramid-shaped block including maxilla, floor of nose, medial orbital walls. Fracture runs: nasal bones, frontal processes of maxilla, lacrimal bones, orbital floor, zygomaticomaxillary suture area, pterygoid plates (middle third)
• Le Fort III (Craniofacial dysjunction): Complete separation of facial skeleton from cranial base. Fracture runs: frontonasal suture, orbital walls, zygomaticofrontal suture, zygomatic arch, pterygoid plates (all)

• Zygomatic complex fracture (malar fracture)
• Isolated zygomatic arch fracture
• Naso-orbito-ethmoid (NOE) fracture
• Orbital fractures (blow-out, blow-in)
• Isolated nasal bone fracture

Zygomatic Complex Fracture (ZMC Fracture)

1. Zygomaticofrontal suture
2. Infraorbital rim/zygomaticomaxillary suture
3. Zygomatic arch (zygomaticotemporal suture)
4. Lateral orbital wall (zygomaticosphenoid suture)
5. Infraorbital foramen area

• Flattening of cheek (malar eminence depression - hallmark)
• Periorbital ecchymosis (black eye)
• Subconjunctival hemorrhage (lateral)
• Infraorbital nerve paresthesia (numbness cheek, upper lip, upper teeth)
• Diplopia (double vision - orbital floor involvement, inferior rectus entrapment)
• Limitation of mouth opening (depressed arch impinging on coronoid process)
• Step deformity at infraorbital rim
• Enophthalmos (sunken eye - orbital volume increase)
• Circumorbital edema

• Temporal (Gillies) approach: Elevator inserted through temporal fossa incision to lift arch - for isolated arch fractures
• Intraoral (Keen's) approach: Buccal sulcus incision, elevate with bone hook
• Carroll-Girard screw: Direct transcutaneous elevation
• ORIF (Open Reduction Internal Fixation):
  • Zygomaticofrontal suture: upper lateral eyelid incision
  • Infraorbital rim: subciliary/transconjunctival/infraorbital incision
  • Zygomatic arch: coronal flap / Dingman approach
  • Fixation: miniplates at 2-3 points

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

Classification of Mandibular Fractures

1. Symphysis / parasymphysis
2. Body
3. Angle
4. Ramus
5. Condyle (head, neck, subcondylar)
6. Coronoid
7. Alveolar

• Simple/closed
• Compound/open (communicates with mouth)
• Comminuted (multiple fragments)
• Greenstick (children - incomplete)
• Pathological

• Favorable: Muscle pull approximates fragments (vertical favorable, horizontal favorable)
• Unfavorable: Muscle pull displaces fragments apart

Fracture of Angle of Mandible

• Pain and tenderness at angle region
• Trismus (limited mouth opening)
• Deviation of mandible on opening (to fractured side)
• Malocclusion - posterior open bite, premature contact
• Step deformity at lower border of mandible
• Paraesthesia of lower lip/chin (if inferior alveolar nerve involved)
• Ecchymosis in floor of mouth (pathognomonic of mandibular fracture)
• Difficulty in chewing

• Champy's method (miniplate osteosynthesis): Preferred for most angle fractures
  • Single miniplate along oblique line (tension band)
  • Monocortical screws
  • Advantages: no IMF, early function, minimal complications
• Two-plate fixation: Superior border + inferior border plates
• Lag screw fixation: Across fracture in favorable cases

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

Clinical Features of Le Fort I (Guerin's Fracture)

• "Floating palate" - detached alveolar segment mobile from rest of skull (gripping upper teeth and rocking)
• Ecchymosis in buccal vestibule (bilateral)
• Guerin's sign: Ecchymosis in palate / pterygoid region
• Step deformity at zygomaticomaxillary junction (absent in pure Le Fort I)
• Anterior open bite
• Cracked pot sound on percussion
• Bilateral circumoral ecchymosis
• Nasal bleeding (epistaxis)

• Pain in upper jaw
• Altered bite / malocclusion
• Difficulty chewing
• Nasal obstruction

Management of Le Fort I

1. IMF first - establish correct occlusion as reference
2. Reduction - disimpact (downward and forward)
   • Walsham's forceps (nasal bones)
   • Rowe's disimpaction forceps
3. Fixation:
   • Miniplates at piriform rim (bilateral) and zygomaticomaxillary buttress (bilateral)
   • Internal wire suspension (older technique)
4. IMF maintained for 4-6 weeks in conservative cases

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5. Complications of Fractures

• Hemorrhage (primary, reactionary, secondary)
• Shock
• Airway obstruction
• Nerve injury (infraorbital, mental, inferior alveolar nerve)
• Damage to adjacent teeth
• CSF rhinorrhoea (anterior cranial fossa - cribriform plate)
• Blindness (optic nerve injury in orbital fractures)
• Diplopia

• Infection/osteomyelitis
• Malunion (healed in wrong position)
• Non-union (failure to heal)
• Avascular necrosis (condylar head)
• Ankylosis of TMJ (post-condylar fracture)
• Osteonecrosis

• Malocclusion
• Growth disturbance in children
• Facial asymmetry
• Chronic pain/dysfunction of TMJ
• Scar formation
• Frey's syndrome (parotid injury)
• Eburnation (bone sclerosis at non-union site)
• Sudeck's atrophy

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6. Timing of Repair of Cleft Lip & Palate

• Rule of 10s: Weight ≥10 lbs (4.5 kg), Hb ≥10 g/dL, Age ≥10 weeks
• Surgical repair at 3 months (10-12 weeks)
• Techniques: Millard rotation-advancement (most popular), Tennison-Randall, Rose-Thompson

• Hard palate: 18 months (some centers at 9-12 months)
• Soft palate: 6-9 months (to allow velopharyngeal competence before speech)
• Optimal: Complete repair by 12-18 months before speech development
• Techniques: Veau-Wardill-Kilner (V-Y pushback), von Langenbeck, Furlow double Z-plasty

• Pharyngoplasty: 4-5 years (for VPI)
• Alveolar bone graft: 9-11 years (mixed dentition, before canine eruption)
• Rhinoplasty/Lip revision: After skeletal maturity (16-18 years)

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7. Anterior Maxillary Osteotomy (Wassmund/Wunderer Procedure)

• Bimaxillary protrusion (dentoalveolar)
• Anterior open bite correction
• Correction of vertical maxillary excess in anterior region

• Tunneling approach (no pedicle incisions)
• Less blood supply - higher risk of necrosis

• Palatal approach
• Better visualization

1. Extraction of bilateral upper premolars (space for setback)
2. Vertical osteotomies distal to lateral incisors
3. Horizontal (transverse) osteotomy above apices
4. Segment repositioned posteriorly/superiorly
5. Rigid fixation with miniplates/wires

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8. Principles of Management of Facial Fractures

1. Life-saving first: Airway, Breathing, Circulation (ABC)
2. Assess neurological status: Head injury exclusion
3. Temporary hemostasis: Compression, nasal packing
4. Definitive imaging: CT scan face
5. Reduce and fix: Restore correct anatomical position and stabilize
6. Restore occlusion: IMF as guide - establish pre-injury occlusion
7. Timing: Early (within 24h) or delayed (7-14 days after swelling subsides) - ideally within 2 weeks
8. Inside-out, bottom-up sequence: Start from mandible (occlusion established), then maxilla, then orbital rim, then forehead
9. Rigid fixation: Miniplates, screws - allow early mobilization
10. Preserve bone: Avoid unnecessary stripping of periosteum
11. Soft tissue management: Proper wound toilet, primary closure
12. Antibiotics: Compound fractures
13. Rehabilitation: Physiotherapy, occlusal rehabilitation

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9. Indications for Open Reduction of Condylar Fractures

• Condyle displaced into middle cranial fossa
• Condyle displaced into external auditory canal
• Foreign body in joint
• Open fracture of condyle with contamination

• Bilateral condylar fractures with anterior open bite
• Condylar dislocation with severely displaced fragments
• Ramus height shortening >5mm
• Displacement angle >30°
• Failed closed treatment
• Patient cannot tolerate IMF (epilepsy, psychiatric disorders)
• High subcondylar fractures in adults (intracapsular)

• Children (risk of ankylosis)
• Unilateral fracture with acceptable occlusion
• Undisplaced fractures
• Subcondylar fracture with minimal displacement

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10. Clinical Features of Le Fort III Fracture (Craniofacial Dysjunction)

• "Dish-face deformity": Total facial skeleton separated from cranium, face appears elongated/flat
• Massive facial edema
• Bilateral periorbital ecchymosis ("Raccoon eyes" / panda eyes)
• Bilateral subconjunctival hemorrhage
• Mobility of entire facial skeleton on grasping and rocking midface (Le Fort III mobility)
• Bilateral infraorbital nerve paresthesia
• Anosmia (olfactory nerve disruption)
• Enophthalmos (orbital volume increase)
• Epistaxis (severe, profuse)
• CSF rhinorrhoea (cribriform plate disruption - test: ring sign on paper, glucose in nasal discharge)
• Telecanthus (NOE involvement)
• Malocclusion - anterior open bite, gagged posterior teeth
• Lengthening of face ("long face deformity")
• Bilateral Battle's sign can occur

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11. Le Fort II Fracture (Pyramidal Fracture)

• Nasal bones
• Frontal processes of maxillae
• Lacrimal bones
• Orbital floor (medial)
• Infraorbital rim
• Anterior and lateral walls of maxillary sinus
• Pterygoid plates (middle third)

• Bilateral periorbital ecchymosis (black eyes)
• Subconjunctival hemorrhage (bilateral, medial)
• Infraorbital nerve paresthesia (bilateral numbness of cheek, upper lip)
• Nasofrontal mobility - nasal block mobile
• Flattening of nasal bridge
• Epistaxis
• Step deformity at infraorbital rim
• Anterior open bite, malocclusion
• CSF rhinorrhoea (if cribriform plate involved)
• Elongation of face

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12. Arch Bars

• Erich arch bar: Most commonly used - thin malleable metal bar with lugs/hooks for rubber bands/wires
• German silver arch bar
• Winter arch bar

• IMF for fracture management
• Orthognathic surgery (for occlusal reference/fixation)
• Splinting teeth
• Distraction osteogenesis

1. Arch bar is bent to conform to dental arch
2. Ligated to each tooth with 0.45mm stainless steel wire
3. Wires passed around contact point of each tooth
4. Upper and lower arch bars connected with 0.45mm wires (IMF) or rubber bands (elastic traction)

• Periodontal damage
• Interference with oral hygiene
• Wire irritation/injury to soft tissue
• Inadvertent swallowing of wire

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13. Classification of Middle Third Facial Fractures

• Le Fort I - Transverse/Horizontal
• Le Fort II - Pyramidal
• Le Fort III - Craniofacial dysjunction

• Isolated zygomatic arch fracture
• Zygomatic complex fracture (ZMC/trimalar fracture)
• Orbital rim fracture

• Blow-out fracture (pure/impure)
• Blow-in fracture
• Orbital rim fracture

• Isolated nasal bone fracture

• Type I: Single central fragment
• Type II: Comminuted without disruption of medial canthal tendon
• Type III: Comminuted with disruption of medial canthal tendon

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14. Bilateral Sagittal Split Osteotomy (BSSO)

• Mandibular prognathism (setback)
• Mandibular retrognathism (advancement)
• Asymmetry correction
• Vertical dimension changes

1. Intraoral incision over external oblique ridge
2. Stripping of medial and lateral periosteum of ramus
3. Medial horizontal cut above lingula (above mandibular foramen)
4. Lateral vertical cut below oblique ridge in body (Dal Pont)
5. Connecting sagittal cut between medial and lateral cuts
6. Splitting with osteotomes
7. Reposition distal (tooth-bearing) segment
8. Fixation: bicortical screws or plates

• Inferior alveolar nerve damage (most common - paresthesia)
• Bad split
• Condylar sag/torque
• Relapse
• Hemorrhage
• Infection

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15. Distraction Osteogenesis

1. Latency period: 5-7 days post-osteotomy (callus formation begins)
2. Activation/Distraction period: Device activated at 0.5-1mm/day (rate) in 0.25mm increments twice daily
3. Consolidation period: No distraction; new bone mineralizes (4-8 weeks per cm distracted)
4. Remodeling period: Device removed, bone remodels

• Mandibular lengthening (hemifacial microsomia, micrognathia)
• Le Fort III advancement
• Alveolar distraction (before implant placement)
• Midface distraction
• Treatment of cleft palate (alveolar transport)

• External (RED device - rigid external distractor)
• Internal (intraoral/extraoral internal devices)

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16. Pyramidal Fracture (Le Fort II) [2M - Short Answer]

• Type: Le Fort II middle third fracture
• Shape: Pyramid-shaped mobile fragment (nose + maxilla)
• Key feature: Nasal complex + maxilla mobile as a unit
• Clinical: Bilateral periorbital ecchymosis, infraorbital nerve paresthesia, nasofrontal step, anterior open bite
• See full answer under Le Fort II above

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17. Define Orthognathic Surgery

1. Correct skeletal jaw discrepancy
2. Establish Class I occlusion
3. Improve facial aesthetics and symmetry
4. Improve function (mastication, speech, airway)

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18. Classification of Maxillary Orthognathic Procedures

• Le Fort I osteotomy: Repositioning entire maxilla (advancement, setback, superior, inferior impaction)
• Le Fort II osteotomy (Naso-maxillary osteotomy)
• Le Fort III osteotomy (Craniofacial osteotomy): Total midfacial advancement

• Anterior maxillary osteotomy (Wassmund/Cupar): Anterior 4-6 tooth segment
• Posterior maxillary osteotomy (Schuchardt procedure): Posterior segments
• Quadrangular osteotomy: Isolation of central palatal segment
• Horseshoe osteotomy

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19. Classification of Mandibular Orthognathic Procedures

• Bilateral Sagittal Split Osteotomy (BSSO) - Trauner & Obwegeser - most versatile
• Vertical subsigmoid/subcondylar ramus osteotomy: For mandibular prognathism
• Oblique ramus osteotomy
• Inverted L osteotomy: Advancement with rigid fixation
• C-osteotomy / Step osteotomy

• Anterior mandibular osteotomy (Hofer procedure): Lower anterior subapical
• Posterior mandibular osteotomy (Köle)
• Total subapical osteotomy

• Genioplasty (osteotomy of chin): Horizontal osteotomy - advancement, setback, vertical changes

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20. Dental Wiring Techniques

• Ivy loop: Single tooth interdental wire loops - quick, for edentulous gaps
• Gilmer wiring: Wire passed around upper and lower teeth together
• Stout multiple loop wiring: Continuous wire with loops for elastic/wire IMF
• Ernst ligature: Figure-of-8 wiring around adjacent teeth

• Erich arch bar + circumdental wires (described above)

• Wire passed under mandible for fixation

• Connects fractured midface to stable superior bony points
• Types: Circumzygomatic, pyriform aperture, frontal bone suspension
• Used when miniplates not available or in panfacial fractures

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21. Types of Blow-Out Fracture / Orbital Blow-Out Fracture

• Orbital floor fractures with intact orbital rim
• Mechanism: Direct blow to eye (globe); hydraulic pressure transmits to thin orbital floor (Hastings and Gilliland; or "buckling theory" - force along orbital rim)

• Orbital floor fracture + fracture of orbital rim (e.g., ZMC fracture)

• Floor blow-out: Most common - herniation of orbital contents into maxillary sinus
• Medial wall (lamina papyracea): Second most common - herniation into ethmoid sinuses
• Roof (blow-in): Upward orbital fracture - compressed orbital volume

Clinical Features of Orbital Blow-Out Fracture:

• Diplopia (double vision - inferior rectus/inferior oblique entrapment in floor fracture)
• Enophthalmos (sunken globe - increased orbital volume)
• Limitation of upward gaze (positive forced duction test)
• Infraorbital nerve paresthesia
• Periorbital ecchymosis, subconjunctival hemorrhage
• Orbital emphysema (blowing nose)
• Enophthalmos may be delayed (initially masked by edema)

• Persistent diplopia in primary gaze
• Enophthalmos >2mm
• Large floor defect (>50% of floor / >2cm²)
• Hypoglobus
• Entrapment with ischemia (white-eyed blow-out in children - emergency)

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22. Champy's Lines of Osteosynthesis

• Mandible loaded in bending creates a tension zone (upper border) and compression zone (lower border)
• Plates placed in the tension zone act as tension bands and resist deforming forces
• Monocortical screws used (avoid inferior alveolar nerve)

• Symphysis/parasymphysis: TWO plates needed (one at lower border, one above) - because torsional forces are greatest here
• Body: Single plate along oblique line
• Angle: Single plate along oblique line (extraoral or intraoral)
• Above mental foramen to symphysis: Upper plate at tooth apices level

• Intraoral approach - no external scar
• No IMF required
• Early mobilization, function
• Simple technique
• Monocortical screws - less nerve damage risk

• Not suitable for severely comminuted fractures
• Two plates needed at symphysis (if not used, may rotate/split)
• Condylar fractures need different approach

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23. Visor Osteotomy

1. Horizontal osteotomy through anterior mandible above mental foramina
2. Superior segment elevated (like opening a visor) while remaining pedicled on floor of mouth musculature
3. Interpositional bone graft placed in the gap
4. Segment fixed in elevated position with plates/screws

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24. Guerin's Sign

• Rupture of descending palatine vessels + pterygoid plexus → ecchymosis under palatal mucosa
• Also associated with bruising of the soft palate / posterior hard palate
• Can also be seen at posterior buccal vestibule

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25. Battle's Sign

• Appears 12-24 hours after injury (delayed - unlike immediate ecchymosis)
• Indicates posterior cranial fossa fracture
• Associated with: petrous temporal bone fracture, transverse/sigmoid sinus injury, facial nerve injury, hearing loss

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26. Coleman's Sign

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27. Malunion

• Inadequate reduction
• Loss of fixation
• Failure to diagnose
• Patient non-compliance

• Facial asymmetry/deformity
• Malocclusion
• Limitation of mouth opening
• Functional problems (chewing, speech)

• Refracture and reposition: If caught early (within weeks)
• Osteotomy and repositioning: If established malunion
• Orthodontic camouflage: Minor discrepancies
• Orthognathic surgery: For significant jaw malunion

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28. Non-Union

• Hypertrophic ("elephant foot"): Adequate vascularity but inadequate stability - heals if stabilized
• Oligotrophic: Poor vascularity
• Atrophic: No callus, avascular - needs bone grafting

• Infection/osteomyelitis
• Inadequate fixation/immobilization
• Excessive bone loss
• Systemic conditions (osteoporosis, radiation, malnutrition)
• Pathological fracture (tumor)
• Excessive periosteal stripping

• Persistent pain, mobility at fracture site
• Fibrous union (mobile but no bone)
• Eburnation (sclerotic bone ends)
• No radiographic evidence of callus/bridging

• Eliminate infection (debridement, antibiotics)
• Rigid fixation (reconstruction plates)
• Bone grafting (autogenous iliac crest - gold standard)
• Distraction osteogenesis
• Hyperbaric oxygen (radiation-induced)

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29. Eburnation

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30. Rigid Internal Fixation (RIF)

• Miniplates (1.5-2.0mm): For mandibular fractures (Champy)
• Reconstruction plates (2.4-2.7mm): For severely comminuted fractures, non-union, continuity defects
• Screws: Monocortical or bicortical, cortical screws
• Lag screws: Compression across fracture

• No need for IMF
• Early mobilization - improved patient comfort
• Better nutrition, oral hygiene
• Reduced muscle wasting
• Allows immediate function
• Better control of fracture segments

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PRE-PROSTHETIC & IMPLANT SURGERY - Answers

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31. Torus

• Torus palatinus: Midline of hard palate, most common oral torus, bony hard, sessile or lobulated
• Torus mandibularis: On lingual aspect of mandible, bilateral, above mylohyoid line, in premolar region

• Asymptomatic, slow-growing
• Normal overlying mucosa
• Hard on palpation
• More common in women (torus palatinus), in populations of Asian and native American descent

• Interference with denture construction (most common)
• Recurrent ulceration from trauma
• Phonation difficulties
• Patient request

• Local anesthesia
• Incision over torus
• Periosteal elevation
• Removal with bur/osteotome/chisel
• Primary closure

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32. Alveoloplasty

• Sharp bony ridges/spicules (post-extraction)
• Undercuts that prevent denture seating
• Irregular/prominent ridge
• Before denture construction

• Simple alveoloplasty: Smoothing sharp edges after extraction with bone file/rongeur
• Intraseptal alveoloplasty (Dean's): Removal of interseptal bone, collapsing cortical plates inward - preserves cortical bone and ridge height
• Radical alveoloplasty: Extensive bone removal - sacrifices ridge height

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33. Pre-Prosthetic Surgeries

• Alveoloplasty
• Torus / exostosis removal
• Ridge augmentation (bone grafting, distraction)
• Implant placement

• Vestibuloplasty: Deepening the vestibule
• Frenectomy/Frenotomy: High/tight frenum removal
• Epulis fissuratum excision: Denture-induced fibrous hyperplasia removal
• Tuberosity reduction: Excessive soft tissue/bone of maxillary tuberosity
• Flabby ridge treatment: Excision of hypermobile soft tissue on ridge

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34. Ridge Augmentation Procedures

• Lateral window approach (Caldwell-Luc modification)
• Summers osteotome technique (crestal)

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35. Genioplasty

• Chin deficiency (retrognenia/microgenia) - advancement
• Chin excess - setback or vertical reduction
• Vertical excess/deficiency - vertical changes
• Facial asymmetry - asymmetric genioplasty

• Advancement genioplasty: Most common
• Setback genioplasty
• Vertical reduction: "Wedge" removal
• Vertical augmentation: Interpositional bone graft
• Lateral sliding genioplasty: Asymmetry
• Alloplastic augmentation: Chin implant (without osteotomy)

1. Intraoral labial sulcus incision
2. Mental nerves identified and protected
3. Horizontal osteotomy below mental foramina (>5mm below foramina)
4. Chin segment repositioned
5. Rigid fixation (miniplate)

• Paresthesia of lower lip (mental nerve)
• Ptosis of chin soft tissue ("witch's chin")
• Asymmetry
• Infection
• Relapse

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36. Vestibuloplasty

• Shallow vestibule preventing denture extension
• High muscle attachments
• Before denture construction
• Combined with ridge augmentation

• Submucous vestibuloplasty (Obwegeser): Tunnel approach - detach muscle from periosteum subperiosteally, leaving mucosa intact
• Secondary epithelializing vestibuloplasty (Clark): Raw area heals by secondary intention
• Skin/mucosal grafting (Kazanjian):
  • Split thickness skin graft
  • Palatal graft
  • Buccal mucosa graft

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37. Implants (Dental Implants)

• Endosseous (most common): Placed within bone - root-form (cylindrical/screw type), blade form
• Subperiosteal: Metal framework resting on bone surface, under periosteum
• Transosteal: Passes through full thickness of mandible (staple implant - obsolete)

• Screw type (most popular - Branemark, Straumann, Nobel Biocare)
• Cylindrical press-fit
• Blade / plate-form

• Titanium (grade 4 pure / grade 5 Ti-6Al-4V): Gold standard
• Zirconia: Ceramic implants
• Titanium-zirconia (Roxolid)

1. Stage I: Implant placed in bone, submerged, 3-6 months healing
2. Stage II: Abutment connection
3. Prosthetic phase

• Edentulous arches
• Single tooth replacement
• Implant-supported overdentures
• Maxillofacial prosthetics (epitheses for nose, ear, eye)

• Uncontrolled diabetes, radiation to jaws, active infection, inadequate bone volume, smoking (relative), osteoporosis, bisphosphonate therapy (MRONJ risk)

• No pain, mobility, infection
• No peri-implant radiolucency
• Vertical bone loss <0.2mm/year after first year
• 85% at 5 years, 80% at 10 years

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