“FREE FIBULA OSTEOCUTANEOUS FLAP FOR RECONSTRUCTION OF MANDIBLE IN A RARE CASE OF AMELOBLASTIC CARCINOMA”.

PRESENTED BY: DR. PRAMOD SUBASH MAXILLOFACIAL SURGERY UNIT DEPT OF HEAD & NECK SURGEY

AIMS KOCHI

CASE HISTORY54 yr old man

chief complaint – Swelling on lower jawmobility of lower front tooth x 1 year

HOPI - since 2 yearsgradually increasing in sizeno h/o of pain, bleeding,

anesthesia/paresthesia of lipno h/o of trauma to the mandible no h/o tooth ache in relation to the lower

teeth. No deleterious habits

PAST MEDICAL HISTORYKnown case of CAD – Inferior wall MI in 1998

Developed APD Stopped cardiac medications Started APD treatment Now not on any drugs

RTA 1 year back – Fractured both bones - left leg Closed reduction done.

EXAMINATION

• Symmetrical face

• Good mouth opening - 3 finger’s breadth

• Poor oral hygiene – few missing teeth.

• Single swelling in the lingual aspect of mandible on the left side(continuous with the bony contour of mandible),

extending from left lower incisor to second premolar

• Measuring 2 ½ x 2 cms, the swelling was firm, non-fluctuant and non-tender

• A small ulcerated area was seen on the swelling which measured around 0.5 cms in diameter

• Expansion of buccal cortex of mandible was palpable though clinically not visible

• There were no palpable neck nodes

• Tooth vitality test - the involved teeth & contra lateral incisors and canines were also non-vital

INVESTIGATIONS

•Orthopantomogram ( OPG)

•CT Scan

•DIFFERENTIAL DIAGNOSIS

• Ameloblastoma

• Odontogenic keratocyst

• Solitary (traumatic) bone cyst

BIOPSY

•Incisional biopsy

HISTOPATHOLOGY REPORT

Diagnosis: Ameloblastic carcinoma

[As long standing history of ameloblastoma is absent, ameloblastic carcinoma could

have arisen de novo from epithelial cell rests of mandible]

AMELOBLASTOMA

PATHOGENESIS

Dental embryonic remnants i. Epithelial lining of odontogenic cyst ii. Dental lamina or enamel organ iii. Stratified squamous epithelium of oral cavity iv. Displaced epithelial remnants

• Odontogenic tumor• Locally invasive• Tends to recur

• Rarely behaves aggressively or shows metastatic dissemination

MALIGNANCY IN AMELOBLASTOMA ?

• Malignant Ameloblastoma

Ameloblastomas that metastasize despite benign histological features in both primary and

metastatic lesions

• Ameloblastic carcinoma

- Show histologic features of both ameloblastoma and carcinoma

- Both primary and secondaries show histologic signs of malignancy

AMELOBLASTIC CARCINOMA

• No definite sex / age/ race predilection

• Mandible most commonly involved area.

• Usually asymptomatic

• perforates bone

• extends into soft tissue

• tends to recur

• Metastasis to regional lymph nodes

• Most common distant metastasis to lungs

TREATMENT PLAN

• Wide excision (segmental mandibulectomy)

• ? Neck dissection (Clinically N0 neck)

• RECONSTRUCTION

WHY RECONSTRUCTION?

• Functional impairment- difficulty in chewing- difficulty in speech- TMJ problems

• Disfigurement

“Two piece mandible”

OPTIONS FOR RECONSTRUCTION

Common

• Mandibular Reconstruction Plate

• Reconstruction plate and bone graft

e.g. Ileac crest

• Contoured titanium trays with bone chips

Other

• Micro-vascular free Flaps

A.Scapula

B. Ilium

C. Radius

D. Fibula

OPTIONS – FREE FLAPS

ADVANTAGES OF FREE FIBULAR FLAP

• Long thin non weight bearing bone

• Initially used to reconstruct long bones

• Distant from head and neck region

• 22 to 25 cms of bone can be harvested

• Segmental multiple nutrient arteries to the bone ( bone can be osteotomised into smaller

fragments by keeping the periosteum intact)

• Relative ease of harvest

FREE FIBULA OSTEO-CUTANEOUS FLAP

•Based on Peroneal artery and vein

• Skin flap receives supply from septo-cutaneous or musculo-cutaneous perforators from the Peroneal artery

Anterior view – Lt. leg Posterior view – Lt. leg