BONE GRAFTS
Dr Ravi K
Reader
Department of Periodontics
MESDC
Bone Grafts
Bone graft are materials used to facilitate bone formation.
Biologic mechanism that supports the use of bone graft materials :
Osteogenesis
Osteoinduction
Osteoconduction
Osteogenesis –
Formation of new bone which is contributed by the
vital osteoblasts originating from the bone graft material
Osteoinduction
stimulate osteoprogenitor cells to differentiate into osteoblasts that then begin a new bone formation.
Osteoconduction
Scaffold/ fillers- allow the ingrowth of capilliaries,
perivascular tissue and osteoprogenitor cells of the
host into the graft.
Classification
Grafts
Bone Derived
Autogenous
Allografts
Xenografts
Non Bone
Derived
Alloplast
Types of Bone Grafts
Autografts – defined as tissues transplanted
from one site to another within the same individual.
Allografts – defined as tissue graft between individuals of same species (i.e humans)
Xenografts – defined as tissue graft between different species (i.e bone from other animal origin)
Alloplast – usually includes any synthetically derived graft material not (coming) from any animal or human origin
Ideal requirements of bone graft:
Biologic acceptability
Predictability
Clinical feasibility
Minimal operative hazards
Minimal postoperative squeal
Patient acceptance
Gold standard - bone regenerative grafting materials.
Osteogenic, Osteoinductive, Osteoconductive properties.
Gives more predictable results
Autografts
AUTOGRAFT
INTRA ORAL
EXTRA ORAL
BONE FROM INTRAORAL SITES
Sources of bone
Healing extraction wounds
Bone from edentulous ridges
Bone trephined from within the jaw without
damaging the roots
Bone removed during osteoplasty and ostectomy
Graft Procurement………..
Bone Trap
Trephine Bur
Bone Shaving Device
Suction Trap
Sources of cortical graft material :
Lingual ridge on the mandible
Exostoses
Edentulous ridges
Bone distal to a terminal tooth
Bone removed by osteoplasty or ostectomy
Mandible or maxilla at least 5 mm from the roots.
Intraoral Cortical Bone
Cortical Bone Chips
2 Large particle size
3. Potential for sequestration
Osseous Coagulum
1. Mixture of bone dust and blood
2. Small particles ground from cortical bone
Bone Blend.
uses an autoclaved plastic capsule and pestle
Bone is removed from a predetermined site
Triturated in the capsule to a workable plastic like
Mass
Packed into bony defects.
Intraoral Cancellous Bone Marrow Transplants.
Cancellous bone can be obtained from :
- Maxillary tuberosity
- Edentulous areas
- Healing sockets.
Maxillary tuberosity :
Good amount of cancellous bone
Ridge incision is made distally from the last molar
Bone is removed with a curved and cutting rongeur.
Edentulous ridges :
Approached with a flap
Cancellous bone and marrow are removed with curettes
Healing sockets :
Allowed to heal for 8 to 12 weeks
The apical portion is used as donor material
Bone Swaging
Edentulous area adjacent to the defect must be present
Bone is pushed into contact with the root surface without
fracturing the bone at its base
Bone swaging is technically difficult, and its usefulness is
limited.
BONE GRAFT FROM THE ILIAC CREST
Indication
material is needed
cortical as well cancellous
bone.
BONE FROM EXTRAORAL SITES
No longer in use owing to some
problems such as
Tibial grafts
Indication
When mostly cancellous bone is required.
Healing Of Autografts
7 days - Initiation of new bone
formation
21 days - Cementogenesis
3 months – New PDL
8 months - Graft fully incorporated
into the host with
functionally oriented fibers
between the bone and
the cementum
Maturation may take as long as 2 years
[Dragoo 1972 ; Dragoo sullivan 1973]
Autografts ……..
Advantages
1. Promotes osteogenesis
2. Risk of disease transfer
avoided
3. Easily procured
Disadvantages
1. Inadequate material
2. Not comfort with
hospitilization
3. Inflicting surgical trauma in
other parts of the body
Allografts
Allografts
Allografts
5. Finally , it is vaccum sealed in glass vials and stored in tissue banks
Types of Allografts:
Frozen Illiac Cancellous Bone and Marrow
Freeze-dried bone allografts (FDBAs)
Demineralized freeze-dried bone allografts (DFDBA)
Irradiated cancellous bone allografts (ICBA)
Allografts
Frozen Illiac Cancellous Bone and Marrow
Possibility of
- Disease transfer
- Antigenicity
- The need for extensive cross matching
These precluded the use of frozen illiac allografts in modern
periodontics
Freeze-dried bone allografts (FDBAs)
The graft is dried at low temperature (lyophilized)
without any liquid phase in the whole process.
Demineralized freeze-dried bone allografts (DFDBA)
The mineral phase of the FDBA is removed, exposing the collagen
and the BMP.
Regenerate bone by osteoinduction and osteoconduction
To induce new bone formation, this bone has to contain sufficient
Quantities of BMP’s.
Disadvantages
Xenografts are obtained from a species other than the
host species.
Cattle bone, coral and products of algae.
Natural hydroxyapatite
Deorganified bovine bone.
Xenografts
Natural hydroxyapatite
Synthesized from the calcium carbonate (CaCO3) skeleton of coral.
Three-dimensional microstructure of natural bone with average pore sizes of 200µ.
The material is highly biocompatible and bonds readily to adjacent hard and soft tissues.
Eg. - Interpore 200
Deorganified bovine bone
Is an inorganic bone of bovine origin.
Eg
Osteograft
Bio-Oss
Most physiological bone substitute; it becomes completely
incorporated and integrated into the human bone after remodeling
Disadvantages of deorganified bovine bone grafts
(besides their bovine origin) are-
Increased risk of a host immune response
Brittleness
Recommendation to be combined with autogenous bone
Mandatory use of GTR membranes with it.
There are three main groups of alloplasts:
(synthetic hydroxyapatite, tricalciumphosphate,
Bioactive glass)
2. Calcium carbonate
3. Composite polymers (resorbable and nonresorbable)
Alloplasts
CERAMICS
Synthetic Hydroxyapatite (HA)
Biocompatible and bonds readily to adjacent hard and soft tissues
Calcium to phosphorus ratio of 10:6
Ex. Calcitite (dense, nonresorbable particulates)
Osteograft
Osteogen
Tricalcium Phosphate (TCP)
Chemically similar to HA
calcium to phosphorus ratio of 3:2
Depending on the sintering temperature
Alpha (α) (1180°C) TCP resorbs very slowly
Ex. Biovision
beta (β) –phase 900°C
beta (β) TCP replaced by natural bone in 8- 12 months
Eg -Augmen®, Synthograf®, and Cerasorb®
Bioactive Glass
proportions as in bone and teeth), sodium salts, and silicon.
with an average of 300-355 µ
layer
Eg-
Bioglass®, Perioglass® , Biogran®
COMPOSITE POLYMERS
Resorbable
Ex. Fisiograft
Nonresorbable
Mixture of polymethylmethacrylate (PMMA) and
polyhydroxylethylmethacrylate (PHEMA)
Ex. Bioplant HTR®
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