2/27 - grafting Flashcards
complications of block graft
dehiscence
fracture of the graft
fracture of mandible
distraction osteogenesis
making bone longer
guided bone regeneration
bone formation only
want bone formation before soft tssue
collagen membrane is resorbable?
yes
vs titanium
clinical handeling better in
resorbable ones
- bioresorbable
sinus augmentation
before - what do need to check
history of sinusitis
post nasal ldrip
sinus pathology
CBCT evaluation of the sinus
residual height of bone over 5 with sinus lift?
- simultaneous
- external sinus life
6-9months healing
implant placement
residual height of bone over 5 with sinus lift?
- simultaneous
- external sinus life
6-9months healing
implant placement
pedicle graft ideal for
soft tissue height augmentation
idel in cases of decreased vascularity of the recipient site
in cases where bone and soft tissue grafting is planned
shallow plat
vs deep
artery closer or farther from CEJ of the teeth
bone grafts are always
prosthetically driven
bone graft healing
non vascularized bone grafts heal through a sequence of events
bone grafts initially undergo partial necrosis - osteocyte dath
followed by an inflammatory stage - existing bone is replaced with new bone by osteoblasts brught n by invading vessels
creeping substitution – the slow process of vessel invasion and bony replacement
creeping substitution
the slow process of vessel invasion and bony replacement
revascularization in cancellous graft
rapidly and completely due to its open architecture that allows easy invasion of blood vessels
revascularization in cortical graft
slowly and incompletely due to its dense lamellar structure
vessels must penetrate along haversan and volkmans canals
inlay vs onlay graft
interposition (inlay) grafts maintained volume and persevered significantly better than onlay grafts
- onlay only get blood from underneath
embriological origin of grafts
those from calvarial and facial sites have SUPERIOR VOLUMETRIC maintenance and survivial over the grafts from rib, tibia, or iliac crest
wolf’s law
normal skeletal bone has the ability to adapt to the physical stresses through the process of remodeling
rigid fixation
results in PRIMARY BONE HEALING
- effects of this on bone grafts are results in bone graft survivial, greater bony union, increase d primary bone healing and rapid revascularization by virtue of graft IMMOBILITY
recipient site factors
grafts placed in an avascular bed do NOT survive well, other factors at the recipient site include prior irriadiation, infection, and tissue scaring
best grafts are __ and __ because
cancellous for apid revacularixation and cortical to resist resorption
example of block grafts
chin ramus body hip calvarium
keys to the graft
● You want rigid fixation
● Want good adaption to the graft
● PASSIVE TISSUE CLOSURE
● AND FOR TO SIX MONTH healing
complications of block grafts
dehiscence
failure of the graft
fracture of the mandible
basic characteristics of barrier membrane
biocompatibility cell oclussion tissue integration spacce making and space maintenance clinical handeling limited suceptibilty to complications
membranes that space making and space maintenance
capacity to resist collapse under in vivo conditions and therefore to create and maintain sufficient volume during the healing process
COLLAGEN AND TITANIUM REINFORCED
NON resorbable membrane
expanded PTFE
polytetrafluoroethylene
rigidity achieved with fluorinated ethylene propylene
complications in GBR
class I - class IV
class I complication in GBR
small exposure less than 3 mm without purulent discharge
class II complication in GBR
large exposure more than 3 mm without purulent discharge
class III complication in GBR
membrane exposure with purulent discharge
class IV complication in GBR
abscess formation without membrane exposure
approahes to sinus augmentation
crestal approach
- internal approach
lateral window approach
info to gather for sinus augmentation
history of sinusitis
post nasal drip?
sinus pathology?
CBCT evaluation of the sinus
one or two stage sinus lift ?
waiting period?
4-5 mm of bone height is a pre-requisite for one stage implant placement and sinus lift
less than 5 mm residual height of bone = NO immediate
wait 6-9 months
soft tissue grafts
subepithelial CT graft
epithelial CT graft
combination
techniwues for soft tissue grafts
tunnel
free graft
pedicle graft
indications for pedicled graft
ideal for soft tissue HEIGHT augmentation
ideal in cases of decreased vascularity of the recipient site
- stays attached to the blood supply
in cases where bone and soft tissue grafting planned
want to increase thickness of attached use?
subepithelial CT grafft
epithelial CT graft
must be split thickness flaps
immobilization is key
benefits of talking to patient about smoking
just three minutes could make a successful case
if stop for 8 weeks post op can reach success rates of non smokers
smoking is ___ indication
relative contraindicication
creeping substitution
osteoconduction
allows for osteioinduction
Once the graft has undergone some amount of necrosis and resorption, it then acts as a scaffold for neoangiogenesis to occur within the graft.
This vessel penetration of the graft allows
osteogenic cells to invade the graft and create new bone formation. This series of
events is termed osteoconduction (creeping substitution)
osteoinduction
During the proliferative
phase of the graft take, certain molecules induce significant amounts of mitosis of
osteoprogenitor cells and then direct these cells to be committed into differentiated
osteoblasts. This phenomenon is called osteoinduction, and of these molecules
bone morphogenic protein (BMP) is one that has been extensively studied and
has been shown to have significant impact on new bone formation, particularly
BMP-2, BMP-4, and BMP-7
three directions to pay attentiont to with implants
mesiodistal
apico-coronal
orofacial dimensions
