Mandibular reconstruction / oral surgery courses

2,610 views
2,199 views

Published on



The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.


Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
00919248678078

0 Comments
15 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
2,610
On SlideShare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
0
Comments
0
Likes
15
Embeds 0
No embeds

No notes for slide

Mandibular reconstruction / oral surgery courses

  1. 1. MANDIBULAR RECONSTRUCTION www.indiandentalacademy.com
  2. 2. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  3. 3. Importance of the mandible Plays a central role for the complex functions of the oral cavity Muscles of the floor of the mouth and the tongue are inserted to the mandible Provides an essential skeletal counterpart for Chewing Deglutition Speech www.indiandentalacademy.com
  4. 4. Prevents collapse of the upper airway by anterior fixation of the hyoid bone and the hypopharynx. Supports the tongue Forms the contour of the lower third of the face Mandibular continuity is thus indispensable for oral functions and requires reconstruction www.indiandentalacademy.com
  5. 5. HCL Classification According reconstructive difficulty H Lateral defects which include the condyle but do not cross the midline L Are basically H defects with the condyle excluded C www.indiandentalacademy.com
  6. 6. C Consist of the central component of the mandible including the four incisors and two canine teeth. For example, Angle to Angle defect would be described as www.indiandentalacademy.com LCL
  7. 7. Inadequate repair leads to Jaw deviation Soft tissue attachments to the mandible are affected Oral incompetence & difficulty with speech , mastication and swallowing fluids Malocclusion and problem with propioception www.indiandentalacademy.com
  8. 8. Reconstruction Refers to the rebuilding of original form and function that have been lost owing to maxillofacial trauma, disease or treatment of that disease. www.indiandentalacademy.com
  9. 9. The Goals of Reconstruction Restablishment of mandibular continuity Restablishment of an osseous-alveolar base Osseous bulk for full prosthetic rehabilitation Capable of withstanding the functional demands Graft must be able to maintain a correct arch form and continuity Reconstruction should be dimensionally and structurally stable Acceptable facial form www.indiandentalacademy.com
  10. 10. Mandibular defects can be restored by four basic methods Alloplastic material Alloplastic with bone Non vascularised bone graft Vascularised bone graft Distraction osteogenesis www.indiandentalacademy.com
  11. 11. Why is bone used for the replacement of native tissues ? It has a natural matrix similar to the material it is replacing. Is strong by nature so that it can support masticatory forces. When bone is a transplant, no immunosuppression is required. www.indiandentalacademy.com
  12. 12. Autograft Bone taken from the same individual. Allograft Bone taken from another individual of the same species. Xenograft Bone from another species. www.indiandentalacademy.com
  13. 13. K – Wire Fixation With the help of hand drilling instrument hole is made in the segment Wire is threaded at the ends If inferior dental canal is present wire is threaded into the canal www.indiandentalacademy.com
  14. 14. Disadvantages Not a rigid fixation Can be used as only temporary fixation Gross facial discrepancy www.indiandentalacademy.com
  15. 15. Mandibular Reconstruction Plate Mandibular reconstruction plates constructed with Stainless Steel (AO plates) Vitallium Titanium. www.indiandentalacademy.com
  16. 16. Reconstruction plates are usually shaped before the mandibular resection. Screws are drilled into the proximal and distal mandible segments. www.indiandentalacademy.com
  17. 17. Advantages Can be used as a temporary spacer to span the missing segment. Can be an alternative until a reconstructive procedure is performed. Used as permanent fixation in patients who are in poor health or medically compromised. Reliable reconstruction with no donor site morbidity and excellent facial contour. Ability to reconstruct the condyle. www.indiandentalacademy.com
  18. 18. Complications Plate exposure Loosening of screws Plate fracture www.indiandentalacademy.com
  19. 19. Alveolar defect with Alloplastic material Organic Materials calcium aluminate calcium apatite calcium sulfate Hydroxyapatite Synthetic Materials methylmethacrylate teflon www.indiandentalacademy.com
  20. 20. Graft act as a supportive matrix or link between native bones. At the interface of the native bone and the transplanted graft, native osteoblast cells begin to infiltrate and revascularize the porous matrix. Osteoblasts deposit new bone & graft is converted into osteum Osteoconduction www.indiandentalacademy.com
  21. 21. Alloplastic Material with Non vascularized Autogenous Bone Graft Used for reconstruction of small to medium size mandibular defects Rib iIium Tibia Fibula Scapula www.indiandentalacademy.com
  22. 22. iliac bone graft Cortical bone Cancellous bone Corticocancellous bone www.indiandentalacademy.com
  23. 23. Cancellous bone grafts consisting of medullary bone contain the highest percentage of viable osteoblasts. Cortical grafts consisting of lamellar bone struts contain large numbers of osteoclasts. The combination of particulate cortical bone and cancellous marrow . provides the best potential for osteogenesis. The particulate nature of the graft allows rapid revascularization. Cortical bone provide structural support www.indiandentalacademy.com
  24. 24. Procedure With no 15 blade skin incision is made Extended to subcutaneous tissues Electrocautery is used to gain haemostatic control Incision is then oriented towards the crest of the iliac bone Subperiosteal dissection in the medial direction is preferred Elevation of the iliac muscle in the medial aspect allows to take adequate bone chuck www.indiandentalacademy.com
  25. 25. Lateral Cutaneous branch of illiohypogastric nerve Lateral Cutaneous branch of subcostal nerve www.indiandentalacademy.com
  26. 26. Rib Graft Ribs on each side of the thorax protects intrathoraxic contents including lungs and heart. We use 4th and 5th and rib for reconstruction because of good costochondral junction Ribs have a pronounced curve from posterior to anterior Ribs allow curve in two dimensions www.indiandentalacademy.com 180 degrees
  27. 27. A 5cm long incision is made in the submammary crease starting 4cm from the mid line Incision is carried out in layers Skin Subcutaneous fat Muscles of the anterior chest wall www.indiandentalacademy.com
  28. 28. Once subperiosteal plane is attained Small raspatory such as Howarth or a larger rougine such as Farabeuf is used to elevate the periosteum Elevator may perforate the pleural cavity Tuduor Edward`s rib shears are introduced and slide along the rib www.indiandentalacademy.com
  29. 29. Alternative to it we can use gauze piece and slide Neurovascular intercostal bundles run in a groove along the lower surface of the rib , so it is protected Rib can provide Cartilage alone used as secondary growth center Combination of cartilage and bone Bone alone www.indiandentalacademy.com
  30. 30. Storage Media Most ideal storage medium is tissue culture media isotonic balanced pH 7.42 contain essential organic and inorganic cell nutrients Next best is the saline Loss of growth factor due to soaking Bone graft can be preserved in blood or blood soaked sponge Temp should be 4 degree C www.indiandentalacademy.com
  31. 31. Alloplastic tray Polyester coated polyurethane is radiolucent and flexible Tray made up of stainless steel is also used Titanium mesh Dacron Vitallium www.indiandentalacademy.com
  32. 32. CAD CAM www.indiandentalacademy.com
  33. 33. Alloplastic crib adapted to the defect & contoured to overlap the host bone ends on each ends Surgeon must ensure that all pores remain open Capillary ingrowth Crib fixation is best if one use at least three screws on each host bone segments www.indiandentalacademy.com
  34. 34. The mesh is packed with autologous particulate cancellous marrowbone Platelet rich plasma Contain platelet derived growth factor Transforming growth factors Insulin growth factors www.indiandentalacademy.com
  35. 35. www.indiandentalacademy.com
  36. 36. BMP Protein complex responsible for osteoinduction BMP is more present in the cortical bone Recombinant technology have now made purified BMP readily available as a commercial product www.indiandentalacademy.com
  37. 37. Healing of the Bone Graft Three ways in which a bone graft can help to repair a defect. Osteogenesis Formation of new bone by cells contained with in the graft Osteoinduction Molecules contained within the graft convert patients cells which are capable of forming bone Osteoconduction Matrix upon which new bone can be formed www.indiandentalacademy.com
  38. 38. Healing After Grafting Graft Bed in which it lies Host www.indiandentalacademy.com
  39. 39. Type of joints Butt Joint Graft is placed end to end without any overlap Mortoise Joint Cortex of the inner aspect of the graft and cortex of the outer aspect of the mandible exposed and joint together www.indiandentalacademy.com
  40. 40. Distraction Osteogenesis Distraction osteogenesis is a method utilizing body’s own healing mechanism to generate new bone Introduced by ILIZAROV in 1951 “Distraction Osteogenesis is a biologic process of new bone formation between the surfaces of bone segments that are gradually separated by incremental traction.” Distraction forces applied to bone also create tension in the surrounding soft tissue, initiating a sequence of adaptive changes termed as DISTRACTION HISTOGENESIS. www.indiandentalacademy.com
  41. 41. Transport Distraction Osteogenesis Technique of regenerating bone & soft tissue in a discontinuity defect An osteotomy is made 1.5cm from the end of the distal stump of bone adjacent to the discontinuity defect creating a transport disc. www.indiandentalacademy.com
  42. 42. Using a distraction device,the transport disc is advanced thro’ the soft tissue discontinuity defect creating new bone within the distraction gap www.indiandentalacademy.com
  43. 43. Latency period From bone division to the on set of traction . This is the time to form reparative callus. Usually 3 -5 Days Distraction Period Time period from application of traction forces to the cessation of traction forces Consolidation Period Time period between the cessation of traction forces and removal of distraction device. This is the time required for complete mineralisation. Usually 8 -12 weeks www.indiandentalacademy.com
  44. 44. Rate Usually 1mm/ day is optimal <0.5mm/day >2mm/day Premature Ossification Fibrous ossification www.indiandentalacademy.com
  45. 45. Advantages of distraction osteogenesis No need of autogenous bone grafting Formation of not only the hard tissues but also of the soft tissues Multi-directional expansion of the skeleton Minimal evidence of relapse The neurovascular elements contained within the distracted bony segment . are also stimulated and regenerated. Limitation Osseous continuity should be there www.indiandentalacademy.com
  46. 46. Vascularised Autogenous Bone Grafts Development of microvascular surgery and free tissue transfer has revolutionized the reconstruction of head and neck Uses microscope with high quality and good optics and a strong light source 200-mm lens is optimal for working Microsurgical instruments are used www.indiandentalacademy.com
  47. 47. Key factor in microvascular surgery is establish high rate of blood flow . into and out of the graft To accomplish the goal large blood vessels selected External Carotid artery Internal Jugular Vein No 8.0 or 9.0 sutures are used www.indiandentalacademy.com
  48. 48. • • • • Radial forearm flap Fibula Scapula Rib www.indiandentalacademy.com
  49. 49. Fibula Fibula is the longest transplantable bone segment found in humans 26cm/40cm Cranial 8cm left to preserve peroneal nerve Distal 8cm left to preserve angle joint Not a weight bearing bone www.indiandentalacademy.com
  50. 50. The peroneal artery and its vein course the inner aspect of the fibula bone in the deep posterior compartment The artery provides vessels nourishing the bone and supporting its blood flow. In reconstruction of the mandible, multiple osteotomies of the fibula are often necessary to reconstruct the ramus& body. www.indiandentalacademy.com
  51. 51. Thank you www.indiandentalacademy.com Leader in continuing dental education www.indiandentalacademy.com

×