Bsso

BSSO FOR my students ,residents

1. BSSO DR JAMEEL KIFAYATULLAH DENTIST PAKISTAN

2. Contraindications of BSSO Severe decreased posterior mandibular body height Extremely thin medial lateral width of the ramus Severe ramus hypoplasia Severe asymmetries

3. Advantages of BSSO Quick healing because of good bony interface therefore predictible bony union Surgery can advance or set back the mandible ,correct most asymmetries and alter the occlusal plane 3) Rigid Fixation can be used eliminating the need for MMF allowing early mobilisation of mandible and easier management of the airway

4. Advantages of BSSO 4) Modifications can maintain the angle of mandible in the original spatial position even in large advancement 5) Major muscles of mastication remain in original position 6) It has good stability

5. DISADVANTAGES Incidence of nerve damage increased i.e Inferior alveolar nerve damage altered sensation of lower lip Unfavorable splits may occur Surgery must create a fracture on the lingual aspect of the ramus Significant asymmetries are difficult to corrrect

6. Complications of BSSO INTRAOPERATIVE COMPLICATIONS Unfavorable osteotomy splits Bleeding Proximal segment malpositioning POST OPERATIVE COMPLICATIONS 1) Mandibular dysfunction(TMD) 2) Relapse 3) Bleeding 4) Neurologic dysfunction(Lip numbness) 5) Wound infection 6) Wound dehiscence

7. procedure 1) G.A AND L.A 2) Incision 3) Subperiosteal dissection and flap elevation 4) Bone cutting 5) Bone spliting 6) Mandibular repositioning 7) Excess bone removal 8) Rigid Fixation 9) Wound closure

8. Corticotomies The procedure starts with three corticotomies . The first cut is made through the lingual cortex just above the mandibular foramen parallel to the occlusion. The corticotomy is extended from the anterior border of the ramus to just behind the entrance of the inferior alveolar canal ( lingula ).

9. FIRST CUT

10. Second cut The second corticotomy is made through the buccal cortex in a vertical direction at the level of the first or second molar.

11. Third corticotomy The third corticotomy connects the first two osteotomy lines along the anterior border of the ascending ramus .

12. The sagittal split The final split is completed with a thin osteotome , splitting the entire ascending ramus from the anterior to the posterior border of the ramus .

13. Steps of BSSO The surgical technique of the sagittal split mandibular ramus osteotomy can be performed in 32 steps Step 1:infiltrate the soft tissue with vasoconstrictor Step 2: the soft tissue incision Step 3:buccal subperiosteal dissection Step 4: superior subperiosteal dissection

14. BSSO STEPS Step 5:exposure of the lingula Step 6:medial ramus osteotomy Step 7:sagittal osteotomy Step 8: buccal osteotomy of the mandibular body Step 9: drill holes for a holding wire Step 10:drill a hole for the condylar positioner

15. BSSO STEPS Step 11: place reference marks Step 12: lavage Step 13: define the osteotomy Step 14:splitting the mandible Step 15:stripping the pterygomasseteric sling Step 16:stripping the medial pterygoid muscle and stylomandibular ligament Step 17: third molars removal

16. BSSO STEPS Step 18:smooth the contact areas of the segments Step 19: place the holding wire Step 20 Note the position of the inferior alveolar neurovascular bundle and the socket of the third molar (if a tooth was present and removed) Step 21:mobilize the bone segments

17. BSSO STEPS Step 22:place the teeth into the planned occlusion Step 23:remove bone from the proximal segment in class III mandibular setback cases Step 24: positioning the condyle Step 25: tightening the holding wires Step 26:placement of the trocar Step 27: drill the holes and for the place of rigid fixation

18. BSSO Steps Step 28:remove the intermaxillary fixation and check the occlusion Step 29: intraoperative diagnosis of a malocclusion Step 30: place intra and extraoral sutures Step 31: place intermaxillary elastics Step 32: Apply a pressure bandage

19. MEDIAL RAMUS OSTEOTOMY

20. A large pear-shaped vulcanite drill is used to reduce the bone and increase the visibility of the lingula .

21. A ) The completed sagittal osteotomy is demonstrated ( arrow 1). Start the buccal osteotomy at the inferior border and connect it to the vertical osteotomy ( arrow 2). ( B ) The buccal osteotomy is completed in a slight posterior medial direction to facilitate the introduction of the Reyneke splitting osteotome and to initiate and direct the split in the proper direction.

22. REFERENCE MARKS

23. A Reyneke splitter is placed into the buccal osteotomy on the lower border of the mandible (1). The splitter and an osteotome , placed into the superior aspect of the vertical osteotomy , are gently rotated (1 & 2). The lower border should separate from the distal segment including the lower border of the mandible (3)

24. The 4 typical fracture lines of bad splits are demonstrated: buccal plate fracture (1), buccal plate fracture including the coronoid process (2), a fracture short of the lingula (3), and a retromolar fracture (4). buccal plate fracture buccal plate fracture including the coronoid process a fracture short of the lingula retromolar fracture

25. The pterygoid muscle and stylomandibular ligament is stripped off the medial aspect of the mandibular angle

26. Positioning of the condyle . Posterior pressure on the positioning instrument (1) and extraoral digital pressure on the angle of the mandible pushing superiorly and slightly anteriorly (2) will give the surgeon control of the proximal segment (3). Once the surgeon is confident that the condyle is positioned correctly in the fossa , the assistant can tighten the positioning wire (4).

27. REMOVAL OF POSITIONING WIRE The positioning wire may be removed at this stage; however, it is optional, and it may serve as additional fixation (1). The reference lines allow for adequate alignment of the segments (2). Three bicortical screws are demonstrated as internal rigid fixation (3).

28. OBWEGESER BSSO

29. DALPONT MODIFICATION

30. HUNSUCK MODIFICATION