swelling_of_jaw_and_surgery_of_mandible_my_ppt.pptx

Ent and head neck surgery

1. Swelling of Jaws and Surgery of Mandible Dr. Prakash Khanal MS ORL-HNS 1 st Year Resident GMSMA of ENT-Head and Neck Studies MMC-TUTH, IOM

2. Road Map WHO classification of Jaw t umours and cysts Cysts of jaw Benign tumours of jaw Malignant tumours of jaw Surgery of mandible Reconstruction of mandible

3. Histological classification of jaw tumour WHO , 1992

4. Neoplasms and Other Tumours Related to Odontogenic Apparatus Benign Odontogenic epithelium without odontogenic ectomesenchyme Ameloblastoma Squamous odontogenic tumour Calcifying epithelial odontogenic tumour ( Pindborg tumour) Clear cell odontogenic tumour Odontogenic epithelium with odontogenic ectomesenchyme with or without dental hard tissue formation Ameloblastic fibroma Ameloblastic fibrodentinoma ( dentinoma ) and ameloblastic fibro- odontoma Odontoameloblastoma Adenomatoid odontogenic tumour Calcifying odontogenic cyst Complex odontoma Compound odontoma

5. Neoplasms and Other Tumours Related to Odontogenic Apparatus Benign Odontogenic ectomesenchyme with or without included odontogenic epithelium Odontogenic fibroma Myxoma ( odontogenic myxoma,myxofibroma ) Benign cementoblastoma ( cementoblastoma , true cementoma )

6. Neoplasms and Other Tumours Related to Odontogenic Apparatus Malignant Odontogenic carcinomas Malignant ameloblastoma Primary intraosseous carcinoma Malignant variants of other odontogenic epithelial tumours Malignant changes in odontogenicc ysts Odontogenic sarcomas Ameloblastic fibrosarcoma ( ameloblastic sarcoma) Ameloblastic fibrodentinosarcoma and ameloblastic fibro- odonto sarcoma Odontogenic carcinosarcoma

7. Neoplasms and Other Lesions Related to Bone Osteogenic neoplasms Cemento -ossifying fibroma ( cementifying fibroma, ossifying fibroma ) Non-neoplastic bone lesions Fibrous dysplasia of the jaws Cemento -osseous dysplasias Periapical cemental dysplasia ( periapical fibrous dysplasia) Florid cemento -osseous dysplasia ( gigantiform cementoma , familial multiple cementomas ) Other cemento -osseous dysplasias Cherubism (familial multilocular cystic disease of the jaws) . Central giant cell granuloma Aneurysmal bone cyst Solitary bone cyst (traumatic, simple, haemorrhagic bone cyst ) Other tumours Melanotic neuroectodermal tumour of infancy ( melanotic progonoma )

8. Epithelial Cysts Developmental Odontogenic "Gingival cysts" of infants (Epstein pearls) Odontogenic keratocyst ( primordial cyst ) Dentigerous (follicular) cyst Eruption cyst Lateral periodontal cyst Gingival cyst of adults Glandular odontogenic cysts; sialo -odontogenic cyst Non-odontogenic Nasopalatine duct (incisive canal) cyst Nasolabial ( naso alveolar ) cyst Inflammatory Radicular cyst Apical and lateral Residual Paradental ( inflammatory collateral , mandibular infected buccal) cvst

9. Cysts of jaw Odontogenic epithelium : responsible for cysts and tumors 3 epithelial structures Remnants of dental lamina (rests of Serres ) – Adult gingival cysts, Odontogenic keratocysts Reduced enamel epithelium – Dentigerous cysts Cell rests of Malassez – Radicular cysts

10. Developmental cysts

11. Gingival cysts of newborn occur on alveolar ridge of newborns. seen only in first few months of life. up to 50% of all newborns. Sessile, normal to yellow or white colour soft tissue cyst , does not have an intra bony component Treatment spontaneously rupture , require no therapy. Simple enucleation / deroofing If cyst large enough to interfere with nursing persist >6 months of age.

12. Dentigerous cyst Second most commom odontogenic cyst a/w crown of unerupted teeth Cyst attached with cervical region of teeth Involvs Mandibular 3 rd molar Maxillary 3 rd molar Maxillary canines Mandibular second bicuspids C/F Arch appears to be missing teeth Usually asymptomatic May cause expansion of bone

13. Dentigerous cyst Radiologic findings: well circumscribed, unilocular radiolucency surrounding crown of unerupted teeth Treatment: Removal of impacted tooth along with enucleation of cyst Large mandibular cyst: marsupialization f/b enucleation

14. Calcifying odontogenic cyst Also known as a Gorlin ’ s cyst Arise from remnents of dental lamina with in gingiva or jaws Peak incidence: 2 nd decade located in anterior portion of jaw . little recurrence potential Clinical and radiological features: Extraosseous lesion : painless gingival expansion. incidental findings on routine radiographic evaluation. initially appear lucent . calcifications - well-circumscribed mixed radiolucent/radiopaque

15. Calcifying odontogenic cyst Treatment and Prognosis Surgical enucleation : complete resolution. Extraosseous lesions often a/w other odontogenic tumors lesion removal only - low recurrence potential

16. Glandular Odontogenic Cyst Sialo - Odontogenic Cyst Clinical and Radiographic Features Common in middle aged adults . Site : 75% in mandible (esp. anterior region .) Multilocular radiolucencies , frequently cross midline Treatment and Prognosis Most amenable to enucleation and curettage . Recurrence potential ( up to 30%) marginal resection. long-term follow-up .

17. R adicular cyst Most common odontogenic cyst Develops at apex of erupted tooth Response to pulpal necrosis secondary to dental caries or trauma C/F: Most asymptomatic ,incidental findings Radiologically : round to ovoid, well circumscribed, contiguous with apex of tooth Treatment: Extraction of infected teeth f/b enucleation of cyst. Complete bony healing with in 6 months

18. Non odontogenic Cysts

19. Nasopalatine Duct Cyst Incisive Canal Cyst Arise from epithelial remnants of embryonic nasopalatine ducts arise in anterior maxilla near incisive foramen Clinical and Radiographic Features M:F= 2:1, 4 th to 6 th decades. Asymptomatic soft tissue swelling in midline of anterior hard palate once lesion has perforated bone.

20. Nasopalatine Duct Cyst Well-circumscribed, heart-shaped , unilocular radiolucency in midline of anterior palate . Treatment and Prognosis Surgical enucleation is usually curative May result in sacrificing nasopalatine nerve and vessel Recurrence is rare .

21. Stafne Bone Cyst Lingual Salivary Gland Depression , Static Bone Cyst not a true cyst. Depression on lingual aspect of posterior body of mandible well-circumscribed radiolucency below inferior alveolar canal in 2 nd /3 rd molar region depression filled with an accessory lateral lobe of submandibular gland No treatment is required.

22. Solitary bone cyst Traumatic bone cyst, hemorrhagic cyst Intraosseous cavity lined by fibrovascular membrane , lacking epithelium. Cysts arise from a traumatic, intraosseous haemorrhage with subsequent bone resorption 2 % of all jaw cysts . Site : posterior mandible Cyst : solitary and often large and non expansile . Well -demarcated and sometimes scalloped edge .

23. Solitary bone cyst : Presence of cavity filled with straw-coloured fluid : virtually diagnostic. Once opened, cavity normally resolves spontaneously Few cases require bone grafting

24. Aneurysmal Bone Cyst rare, expansile osteolytic bone lesion . large blood-filled spaces without endothelial lining not a true cyst Clinical / Radiographic Features age :first 3 decades of life , predilection for posterior part of jaws. firm swellings , can be diffuse. Radiologically expansile radiolucencies that can displace teeth . Treatment and Prognosis managed by curettage

25. Odontogenic Tumors Arise from epithelial or mesenchymal cells, or both, associated with tooth structures. Most are true neoplasms Some behave as hamartomatous growths. C/F asymptomatic swellings, which can eventually cause bone loss, tooth displacement, and jaw expansion. Rarely cause sensory nerve dysfunction .

26. Odontoma Not true neoplasms Hamartomatous growths form during normal tooth development, then reach a fixed size contains enamel, dentin , cementum , and pulp tissue . Classified as Compound: if resembles tooth-like structures or Complex : if appears as an amorphous mass.

27. Odontoma Clinical and Radiographic Features First two decades, no sex predilection Asymptomatic, discovered on routine radiographic examination. Can block eruption of a permanent tooth. Radiographically , radiopaque masses with well-demarcated border . Treatment and Prognosis Enucleation and curettage -curative No recurrence.

28. Ameloblastoma Most common odontogenic tumor . Arises from residual epithelial elements of tooth development : reduced enamel epithelium rests of Serres rests of Malassez basal layer of the oral mucosa. Can also develop from within a dental follicle or a dentigerous cyst . Classification Solid or multicystic Unicystic Peripheral

29. Ameloblastoma Clinical/Radiographic Features locally aggressive , slow growth Usually asymptomatic -does not alter sensory nerve function. Common site : posterior mandible peak occurrence : 3 rd /4 th decades, no sex predilection. Radiographically : unilocular or multilocular radiolucency, with ill defined borders Buccal and lingual cortical expansion is common, even progressing to cortical perforation

30. Ameloblastoma Treatment and Prognosis Enucleation and curettage . More aggressive treatment If grows into/through connective tissue layer of lesion If recurs Resection : 1.0- to 1.5-cm bony margin and one uninvolved overlying anatomic barrier margin

31. Adenomatoid Odontogenic tumor Benign hamartoma of odontogenic epithelium Slow , progressive growth Clinical and Radiographic Features 2-3 rd tumor 2-3 rd a/w unerupted tooth 2-3 rd in canine , 2-3 rd in maxilla ; 2-3 rd in young females (adolescents and teens ) Radiographically : well-circumscribed, unilocular radiolucency a/w impacted tooth . Treatment and Prognosis curettage alone is curative. Bony regeneration of defect usually occurs in 1 year in younger patients . No Recurrence

32. Pindborg Tumor Calcifying Epithelial Odontogenic Tumor < 1% of all odontogenic tumors Arise from epithelial rests of dental lamina or reduced enamel epithelium Clinical and Radiographic Features Slow growing, firm , painless swelling, in posterior mandible . molar area :most frequent region does not alter nerve function. Peripheral variant soft tissue swelling in anterior aspect of mouth

33. Pindborg Tumor Radiologically : Diffuse radiolucent lesions If large or mature : areas of faint opacities - calcifications Associated with crown of impacted tooth . Treatment and Prognosis Resection 1-cm bony margin along with any necessary soft tissue Recurrence reported-long-term follow-up recommended . Peripheral variant treatment local excision with 5-mm margin , including underlying periosteum .

34. Odontogenic Myxoma derived from odontogenic ectomesenchyme rare in non tooth-bearing portions of jaws/ facial bones Clinical and Radiographic Features Asymptomatic, slow growing potential to displace teeth or resorb roots, but does not alter sensory function . all portions of jaws , most frequently posterior mandible .

35. Odontogenic Myxoma Radiographically : unilocular or multilocular radiolucency Honeycomb appearance Treatment and Prognosis Curative treatment : resection with a 1- to 1.5-cm bony margin and a layer of overlying soft tissue. Recurrence: if only enucleation and curettage done

36. Ameloblastic Fibroma true neoplasm composed of odontogenic epithelium and ecto mesenchyme . epithelium resembles dental lamina or ameloblastoma mesenchyme resembles dental papilla or myxoma Clinical Features young patients painless swelling, usually in posterior mandible.

37. Ameloblastic Fibroma Radiographic Features unilocular or multilocular radiolucency, often over an unerupted tooth and often displacing the tooth Treatment and Prognosis enucleation and curettage bony defect repair within approximately 1 year. If recurrence : consider ameloblastic fibrosarcoma

38. Non odontogenic lesions of jaws

39. Torus Developmental overgrowth Arise because of bone stress 2 sites Torus palatinus : if occurs on midline of palate Torus mandibularis or lingual tori .: When occur on lingual aspect of mandible

40. Torus Clinical / Radiographic Features Palatal torus : smooth ovoid appearance or multiple pedunculated loculations , normal pink overlying mucosa. If grow large : impair speech or feeding or prohibit fabrication of maxillary prosthesis require surgical excision. Mandibular torus : commonly bilateral , slow growth can reach sizable proportions, affecting speech/feeding/ use of a lower prosthesis .

41. Torus Treatment and Prognosis Removal if interfere with normal function / fabrication and placement of a prosthesis

42. Osteoma Hamartomas or reactive proliferations of bone composed of dense compact bone Arises on Surface of bone : P eriosteal osteoma Within bone : E ndosteal osteoma If multiple osteomas : consider Gardner syndrome

43. Osteoma Clinical and Radiographic Features Slow-growing , exophytic bony masses mandibular angle : common site incidental finding on routine radiographic evaluation well-circumscribed radiopaque mass Treatment and Prognosis Asymptomatic single lesions : follow up clinically and radiographically Surgical excision : for lesion requiring biopsy little chance for recurrence.

44. Osteochondroma benign hamartomas occur in mandibular condyle or coronoid process proliferation of epiphyseal cartilage into surrounding tissues. Clinical and Radiographic Features 2 nd and 3 rd decade, M:F = 2:1 slow growing lesion swelling and pain , deviation of teeth and chin pointing toward the unaffected side . Radiographically, irregular popcorn like radiopaque mass on medial side of the condyle or replacing coronoid

45. Osteochondroma Treatment and Prognosis Lesions affecting coronoid process coronoidectomy with minimal removal of attached temporalis muscle tendon . Lesions of condyle condylectomy Immediate reconstruction costochondral graft or an alloplastic condyle. Recurrence is rare .

46. Ossifying Fibroma Cemento -Ossifying Fibroma True benign tumors of mesenchymal origin strong predilection for tooth-bearing portion of jaws slow-growing , expansile lesion can grow large resulting in profound facial disfigurement.

47. Ossifying Fibroma Clinical and Radiographic Features woman in 3 rd to 4 th decade Immature lesion initially radiolucency, eventually radiopaque. Aggressive lesions expand cortices of jaws , frequently displace adjacent structures. In mandible midbody growth at inferior border , enlarging outward and downward as if hanging off lower lateral border .

48. Ossifying Fibroma Treatment and Prognosis Enucleation and curettage if detected early Resection for larger lesions. 5-mm margin is appropriate Recurrence is rare . Juvenile ossifying fibroma a rare variant more aggressive lesion appearing at a younger age predilection for the maxilla.

49. Fibrous Dysplasia Not a true neoplasm Tumor like condition Normal medullary bone is replaced with fibrous connective tissue mixed with irregular bony trabeculae . commonly occurs in one bone : monostotic rarely multiple bones : polyostotic Polyostotic fibrous dysplasia component of McCune - Albright syn drome café -au- lait skin macules multiple endocrinopathies : hyperthyroidism or precocious puberty

50. Fibrous Dysplasia Clinical and Radiographic Features slow-growing asymptomatic process, self-limiting bony hard swelling tooth displacement , malocclusion Lesions of midface , calavarium , or skull base progressive facial distortion cranial nerve dysfunction via compression . Starts in 1 st decade and ceases when bone reaches maximal growth / maturation . Early lesions radiolucent, become opaque as lesion matures. ground-glass appearance on radiographs .

51. Fibrous Dysplasia Treatment and Prognosis Surgery : indicated in disfiguring lesion cranial nerve dysfunction patient choice delayed until affected bone reaches maturity Recurrence : if treated during an active growth period . Sarcomatous transformation : rare

52. Vascular Malformations Developmental lesions, affect soft tissue or bone. Not present at birth Classified as arterial (high-flow) venous (low-flow ) malformations. Arteriovenous fistulas : high-flow lesions .

53. Vascular Malformations Clinical features Slow growing, asymptomatic , expansile lesions Mobile teeth and can even appear elevated. Thrills or bruits on physical examination . Radiologically well circumscribed radiolucencies or mixed radiolucent/radiopaque . CT or MRI to ascertain extent of lesion Angiography To determine primary vascular inflow Presence of any contralateral vascular contributions.

54. Vascular Malformations Treatment and Prognosis Preoperative selective embolization followed by resection Hypotensive anesthesia reduce intraoperative bleeding . Venous malformations intralesional injections with coils or sclerosing agents. If adequate thrombosis , can be curettaged

55. MALIGNANT TUMOURS ARISING IN AND AROUND THE JAWS

56. Head and neck sarcomas Rare , about 10% of all sarcomas . Two clinical groups – arising in bone and soft tissue Biphasic age distribution, 80–90 % in adult life. Rhabdomyosarcoma : approx. 4–5 % of all childhood malignancy . Common primary bone tumors in head and neck Osteosarcoma Chondrosarcoma Fibrosarcoma Malignant fibrous histiocytoma Ewing’s sarcoma

57. Rhabdomyosarcoma Third most common neoplasm in childhood Most common soft tissue sarcoma of childhood Approx. 35% of children have disease in head and neck Approx. 50 % tumours occur in age <5 years Sites of involvement Orbital tumours :10 % Parameningeal ( nasopharynx , nasal cavity, paranasal sinuses, middle ear, mastoid, pterygoid fossa) : 20 % Other head and neck sites: 10 % Parameningeal site : risk of intracranial spread and cerebrospinal fluid (CSF ) involvement.

58. Rhabdomyosarcoma Presentation and Evaluation pain and swelling Paranasal R habdomyosarcoma nasal obstruction , bloody nasal discharge . Tumors within ear bloody discharge , persistent otalgia despite treatment Lymph node involvement 3 to 36 percent Metastases haematogenous lymphatic spread Common sites : lungs, bone and bone marrow.

59. Rhabdomyosarcoma Subtypes Embryonal : most common , 60% of tumors . botryoid ( subtype of embryonal ) ; 5% of cases Alveolar : 20% of affected children Pleomorphic : features of both embryonal and alveolar subtypes Investigation: Complete blood count, electrolyte panel Liver and renal function tests, coagulation studies CT scan of the chest 99mTc diphosphonate bone scan Bilateral aspiration and biopsy of iliac bone marrow.

60. Rhabdomyosarcoma Treatment Multimodality approach Role of surgery to evaluate extent of lesion biopsy of tumour . Wide surgical removal If easily accessible polypoid lesion Chemotherapy Combination of cisplatin, etoposide , and dacarbazine Other agents Ifosfamide Etoposide or doxorubicin for new and recurrent rhabdomyosarcoma

61. Rhabdomyosarcoma Radiotherapy to eradicate residual tumor cells at primary site to treat gross persistent disease Overt parenchymal , meningeal, or cerebrospinal fluid involvement whole-brain irradiation intrathecal chemotherapy Prognosis Excellent with early tumours ( > 80 % survival ). Relatively poor in advanced tumours Meningeal involvement : five-year survival < 10 %

62. Ewing’s sarcoma Arise primarily in bone, soft tissue presentation may be seen . 10–15 % of primary bone tumours Peak age : 10 to 20 years . Presentation pain and swelling of affected area. <2 % arise in skull bones Systemic symptoms: fatigue , weight loss , fever Lymphatic spread - unusual . 20 % : metastases at time of diagnosis, usually lungs, but bone and bone marrow.

63. Ewing’s sarcoma Principles of management Multi agent chemotherapy: 4 to 6 cycles Followed by Reimaging and Local therapy Surgery, radiotherapy or both Radiotherapy if surgery is mutilating surgical margins are positive Poor response to chemotherapy Adjuvant chemotherapy 12–14 cycles, with reduced intensity regimens ifosphamide and or cyclophosphamide + either actinomycin and doxorubicin.

64. osteosarcoma Osteosarcoma in craniofacial region : 5 % of all osteosarcomas Presentation median age : 4 th decade higher proportion : low-grade tumours Most subtypes can occur in head and neck. Osteoblastic not otherwise specified (NOS ) : most common (75 %) chondroblastic (16 % ). Fibroblastic , juxtacortical and telangictatic subtypes : uncommon. Majority arise in mandible and maxilla .

65. osteosarcoma

66. osteosarcoma Management of head and neck osteosarcoma Surgical treatment for a low-grade osteosarcoma total excision of tumor segmental mandibulectomy / Maxillectomy Effects Chemotherapy Unclear due to higher proportion of lower grade tumours in head and neck Radiotherapy or chemothepary for low grade tumor: controversial as neither has proven to be beneficial Improved survival over last 20 years current survival : approx. 60 %

67. chondrosarcoma Group of tumours of varying behaviour . Peak age: 5 th to 7 th decade. Central types conventional dedifferentiated mesenchymal clear cell types Extraskeletal types myxoid Arising in osteochondromas associated with a multiple exostosis syndrome.

68. chondrosarcoma majority in adults and children are low grade . Surgery treatment of choice, usually without adjuvant therapies. Chemotherapy and radiotherapy Chondrosarcoma (except mesenchymal and dedifferentiated subtypes) resistant to both these therapies

69. Malignant odontogenic tumours represent 0–6.1 % of all odontogenic tumour Includes Malignant ameloblastoma . Ameloblastic carcinoma

70. Malignant ameloblastoma Metastasizing ameloblastoma Histologically resemble ameloblastoma Interval between diagnosis of tumour and manifestation of metastases : about 12 years Metastases lung (88 % ) lymph nodes (27 % ). Distant metastases bone , brain, kidney, small intestine and liver

71. ameloblastic carcinoma Very rare tumour found primarily in mandible wide age range, no sex or race predilection. Variable presentation: predominantly cystic lesion with benign clinical features or large tissue mass with ulceration, bone resorption and tooth mobility . Clinical course is aggressive extensive local destruction . Direct extension of the tumour lymph node involvement metastasis to various sites

72. Treatment Surgical resection with 2–3 cm margins and neck dissection. Postoperative radiation therapy also must be considered. Prognosis is guarded with 5-year survival rates less than 40 %. Distant metastasis associated with poor prognosis palliative chemoradiotherapy may be indicated. Recurrence rate >60 %.

73. Metastatic tumours of the jaw Includes Carcinoma of lung Adenocarcinoma of breast Prostate Kidney Thyroid Liver Most common site within jaws : posterior mandible. Presentation Loosening of teeth Unilateral numbness of the chin Eventually ulceration of the soft tissues . Treatment : palliative chemotherapy and/or radiotherapy.

74. Surgery of mandible

75. Mandibular resections Segmental : whole height of the mandible : leading to mandibular discontinuity Marginal :only alveolar bone is resected Marginal defects reconstruction to improve dental rehabilitation placement of dental implants. Segmental defects reconstruction to provide mandibular continuity.

76. Loss of mandibular continuity laterally (posterior to mental foramen deviation of mandible towards resected side dental occlusion affected. Loss of mandibular continuity anteriorly (anterior to mental foramen ) functional problems Andy Gump deformity

77. CLASSIFICATION OF MANDIBULAR DEFECT Boyd et al., 1993 Mandibular defect classified as H, C, L: H – lateral defects of any length including condyle L – as above but condyle not included C – entire central segment from lower canine to canine .

78. CLASSIFICATION OF MANDIBULAR DEFECT A combination of letters is possible e .g. a defect from angle to angle of mandible is LCL. For a soft tissue defect: o – neither skin or mucosa affected s – skin m – mucosa . s m - through and through defect

79. CLASSIFICATION OF MANDIBULAR DEFECT Urken et al., 1991 anatomic designations, including separate components condyle ( C ) ramus ( R ) body ( B ) total symphysis ( S ) hemisymphysis ( S H) palate ( P ). Includes detailed description of soft tissue and neurologic deficits.

80. aims of mandibular reconstruction Restore facial dimensions (facial height, width and projection). Ideal reconstruction for a segmental mandibulectomy restores oral competency maintains occlusal relationships with remaining teeth allows for prosthetic dental restoration restores bone continuity restores facial symmetry and contour to lower third of face

81. Mandibular reconstructive ladder No bony reconstruction Direct soft tissue closure Local flaps Soft tissue interposition Alloplastic materials Bony reconstruction Non-vascularized bone with or without soft tissue flap: free bone graft, costochondral graft Vascularized bone: pedicled flap, free flap Distraction osteogenesis TMJ reconstruction Dental implants

82. alloplastic materials Must be biocompatible able to withstand the forces sustained by mandible in mastication . Materials medical polymers ceramics metals Titanium reconstruction plates THORP (titanium hollow osseointegrated reconstruction plate ) Use mandibular reconstruction for advanced cancers will die of their disease within two years

83. Free bone grafts Non vascularized bone grafts Defects < 5 cm in length in healthy surrounding soft tissue not to be treated with postoperative radiotherapy Bony free flap longer defects patients with poor surrounding soft tissues that has been/may be irradiated Types of non-vascularized bone grafts autologous allogenic xenografts Best site for autologous bone : anterior or posterior iliac crests .

84. Non -vascularized bony reconstruction Advantages quick and easy technique no viable neck vessels required no risk of microvascular failure. Disadvantages healthy bed of surrounding tissue required high risk of bone resorption high risk of infection increased complications with radiotherapy

85. Costochondral rib grafts Main role Reconstruction of temporomandibular joint. Similar in size to native condyle Prevention of ankylosis at skull base . Aims of condylar reconstruction Restore ramus length and thus vertical face height Restore occlusion Ensure new TMJ movements allow normal mastication , speech and growth in children.

86. VASCULARIZED BONY RECONSTRUCTION OF MANDIBLE Vascularized bone may be transferred as: Pedicled osseous flaps Microvascular bone transfer . Bony free flaps routinely used for mandibular reconstruction: Fibula flap Deep circumflex iliac artery (DCIA) flap Scapula flap Composite radial flap.

87. Fibula flap Advantages length of bone available – upto 26 cm available for transfer only single flap that can be used for total mandibular reconstruction good bone quality and reasonable quantity pedicle length, consistent anatomy two team operating possible . Disadvantages high incidence of atherosclerosis in lower limb vessels lack of height of bone.

88. Deep circumflex iliac artery flap Advantages Best quality and quantity of bone Ideal for dental implants and rehabilitation ; Reduces osteotomies required Predictable anatomy Two team operating possible Disadvantages Poor pedicle length High risk of hernia formation

89. Composite scapula flap Advantages good donor scar, minimal donor site morbidity reasonable bone quality and quantity best flap for complex defects . Disadvantages two team operating is not possible increasing operating time bone quality and quantity not as good as fibula or DCIA flaps .

90. Composite radial flap Advantages thin pliable skin consistent anatomy good pedicle length two team operating possible . Disadvantages poor bone quality and quantity poor healing , may lead to tendon exposure poor cosmetic result risk of fracture of residual radius altered sensation to the thumb decreased function of the hand.

91. DISTRACTION OSTEOGENESIS Technique of growing new bone by distraction of pre-existing bone . Four main stages: Osteotomy – cuts through bony cortex . Latency time between osteotomy and start of distraction. allows formation of a primitive callus Distraction optimum rate of 1.0mm per day : four movements of 0.25 mm per day. Consolidation – new bone is stabilized for up to 4 weeks.