1. Bone Grafts

2. CONTENTS Introduction Clinical Importance. Selection of material.
Case selection.
Mechanism of Bone Graft Materials
Classification of Bone Graft
Preoperative preparation
Graft management
Postoperative management/periodontal maintenance
Conclusion

3. Bone Grafting
Bone graft – Biomaterials which have the characteristics of living bone tissue,that are surgically inserted into the intact tissue of the host to aid in regeneration. ,.
Bone grafting is a surgical procedure that replaces missing bone with material from the patient's own body, an artificial, synthetic, or natural substitute.

4. Clinical Importance
Bone grafting is performed to reverse the bone loss / destruction caused by periodontal disease, trauma, or any other periodontal defect.
It is also used to augment bone to permit implant placement, such as augmenting bone in the sinus area for implant placement.
Augmenting bone to enhance the fit and comfort of removable prostheses.
To enhance esthetics of a missing tooth site in the smile zone.

5. Conditions governing the selection of a material.
Bio - compatability.
Clinical feasibility.
Predictability.
Minimal operative hazards.
Minimal postoperative sequel.
Patients acceptance.

6. Case selection.
Bone grafting can be done only in areas with high vascular supply.
3 wall and 2 wall vertical defects have rich blood supply thus prognosis will be good if bone grafting is done in these areas.
Horizontal and hemiseptal defects have reduced blood supply thus show poor prognosis.

7. Working of Bone Graft Materials
OSTOGENESIS - Contains bone forming cells
OSTEOCONDUCTION - Serve as scaffold for bone formation
OSTEOINDCTION - Matrix of bone grafting material contains bone inductive substances

8. Classification of Bone Graft
Based on the source of the graft.
Autogenous - bone taken from one area of the individual and grafted in another area of the same individual.
Xenograft-graft is obtained from a different species.
Allograft - graft obtained from another individual of the same species.
Alloplasts - synthetic inorganic material.

9. Based on the size of the graft.
Enblock graft- an entire piece of cortical bone or synthetic material is taken for grafting.
Particulate graft- graft material is made into tiny particles and used.

10. Autografts :
Widely used in periodontics for treatment of intrabony defects.
Promotes bone healing through osteogenesis & / or Osteoconduction.
Can be harvested from either intraoral or extraoral donor sites.

11. Autografts from intraoral site
Sources include:
Maxillary tuberosity
Exostoses or tori
Healing extraction wounds
Healing Extraction sites
Bulbous Edentulous ridges.
Mandibular symphysis
Mandibular body
Osteoplasty /Osteotomy sites

12. Bone Grafts harvested from intraoral sites are:
Osseous coagulum
Bone Blend
Intraoral Cancellous Bone Marrow Transplants
Bone swaging
Autografts from extraoral site
Schallorn (1967/ 1968) introduced the use of autogenous” HIP MARROW “Grafts (iliac crest marrow) in treatment of intrabony defects.

13. Allografts:
Allografts used in the treatment of intrabony defects could be:
Freeze-dried bone allograft (FDBA)
Demineralised freeze-dried bone allograft. (DFDBA) .
frozen iliac crest marrow.

14. Freeze dried bone allografts (FDBA)
Osteoconductive
Cortical bone is defatted, cut into pieces, washed in absolute alcohol , deep frozen, freeze dried & vacuum sealed.
Ground particle size : 250 – 750 micron

15. Decalcified Freeze dried bone allografts (DFDBA)
Decalcified with 0.6N Hcl , washed in sodium phosphate buffer & vacuum sealed to expose the bone inducing agent, bone morphogenic proteins(BMP).
These proteins are osteoinductive
ADVANTAGE:significant probing depth reduction, attachment level gain. more osteogenic than FDBA.
DISADVANTAGE: potential of diseases transfer from the cadaver.

16. Xenografts: Anorganic bovine bone (ABB) . Boplant- calf bone
Kiel bone- calf or ox bone.

17. Alloplasts: Synthetic inorganic inert material
Synthetic graft material function primarily as defect fillers. -World Workshop (1996)

18. Alloplasts: Synthetic inorganic inert material Absorbable materials
Classification: on the basis of their ability to be resorbed as:
Absorbable materials
Nonabsorbable materials
Porous hydroxyapatite
Dense hydroxyapatite
Bioglass
Ceramics,
Beta tricalcium phosphate
Hydroxyapatite
Calcium sulfate

19. Defect Selection

20. Preoperative preparation
Perform plaque control .
Occlusal therapy consisting of adjustment or splinting of teeth .
A pre-procedural rinse with a substantive antimicrobial agent, such as 0.12% chlorhexidine gluconate for 30 seconds, immediately prior to the surgery can help reduce intraoral bacteria .

21. Anesthesia Regional Anesthesia for patients comfort
Local infilteration with epinephrin to facilitate hemostasis

22. Flap design
A sulcular incision full thickness flap is reflected. A three wall intrabony defect is visualized at the distal of the first molar.

23. Defect or root debridement
Rotary instrumentation using a multifluted surgical length bur on a high-speed handpiece is needed to gain access to the depth of the lesion and to plane the root surface, which is subsequently treated with citric acid (pH 1).

24. Graft management
The choice of graft material should be based on clinical considerations, including treatment objectives and potential patient maintenance.
After suture removal ,the surgical site is inspected carefully and any excessive granulation tissue is removed .
The patient is provided with post surgical maintenance instructions.
There are no reports of disease transmission, graft rejection or ankylosis after the use of demineralized freeze-dried bone allograft.

25. Graft material in a dappen dish.

26. Placement of demineralized freeze-dried bone allograft is accomplished with light incremental pressure so that the graft overfills the defect. The root surface has been treated with citric acid (pH 1) and the defect has been decorticated.

27. Flap closure
A monofilament suture is used to close the flaps by primary closure.

28. Postoperative management/periodontal maintenance
Post operative antibiotics to aid in prevention of post operative infections.
Topical antimicrobial rinse aids in plaque control.
Postoperative visits include plaque removal
(both mechanically and with topical chlorhexidine)
Periodontal probing or recording of attachment levels should not be done prior to 3-6 months, since probing force may damage the healing site, thereby diminishing the regenerative outcome

29. Pre op
Post op

30. Pre op
Post op

31. Probing
BEFORE SURGERY
AFTER SURGERY

32. Conclusion
Bone grafts benefit patients with functional and esthetic defects.
Bone graft materials aids in regeneration of bone in periodontal defects.
Ongoing research – bioactive/osteoinductive.