L 6 Flashcards
Osteoinduction
Mesnechymal osteoprogentior cells within graft area differentiated into OSB to form bone
Bone matrix
bone matrix–>bone inductive proteins–> host cells–> OSB
BMP Bone morphogenic protein
Initiates osteoinduction
BMP2 and 7 only commercially available
higher cortical vs cancellous bone
Osteoconduction
New bone from host derived or transplanted osteoprognetori cells along bio framework
Provide only passive framework or scaffolding does not produce bone
Osteogensis
Form new bone from osteoprogenitor cells
have osteoindcutve and conductive properties
osteogenesis only in
autogenous only
Phase 1 osteogenis
Transplanted cellular bone produces new osteoid
Considerable cell death may not lead to impressive regeneration
Most active within 4 weeks
Amount bone generated depends on
survival amount of transplanted OSB
Relies on external blood supply to diffuse through
BMPs brought in cause surrounding bone to develop into new bone
Phase II osteogenesis
Angiogeneis and fibroblastic proliferation from graft bed after grafting
Osteogenesis from host CT soon begins
will only grow in wherever phase I lived
Initial woven bone resorbed and replaced by lamellar bone; as initial graft resorbed BMPs released from matrix
begins at 2 weeks peaks at 6 weeks
Autograft
Gold standard
Same inidvidual
possible osteogenic properties
2 surgical sites
Calvarium
good for nasal or large facial fractures thin
can’t go deep mostly cortical bone grafts
Rib
Can harvest with cartilage for TMJ
costochondral grafts good to restore TMJ in growing patients
Pedicel grafts
fibula radial forearm
Antioer poster iliac creast
Young patient with ameloblastoma of mandible
if mostly cortical bone
may not have osteogenic potential
Free Flap
lots of bone different no phase i or 2
have to reanastamose BV
Allograft/Homograft
Same species (cadaver) Highly processed what perio uses
Osteoconductive-good framework minimal induction
Allograft advantages
replaced by patients own bone
no do not site morbitidy
readily available
Allograft disadvantages
No viable cells for phase I osteogenisis longer cosnolidation period encapsulation disease transmision graft host ruction expenisve
Xenograft
Different species
Osteoconductive; possible carrier for inductive properties
Less processed than allograft
limitless no donor site morbidity
expense
longer consolidation period
diseae
patient acceptance
Alloplast
Synthetic not of human or animal think plastic
Osteocondcutive- carries inductive proteins
silicon glass bead calcium phosphate hydroxypatie
alloplast disadvanted
prolonged consolidation
foreign body
encapsulation
cost
Recombinate Graft
recombinant BMPs 2 and 7
BMP 2
approved for sinus floor augmentation and mandibular defect graft
good site because protected by walls
Recomb disadvantages
does not hold shapes flattens out
expesnive
swelling sterility
socket grafting
small volume allograft or xenograft sufficient
osteocondcution adequate to produced desired healing
Sinus floor augmentation
small defects–> allogenic or xenogeneic
Larger–> BMP carrier or autogenous bone iliac crest or tibia
Only grafting for implants
autogenous intraoral donor sites or iliac crest
Resotre both vertical and horizontal ridge drefcines
