soft tissue- Grafting

Question 1

bone augmentation types

Answer 1

1. block graft
   - take block of bone from patient
   - adding volume
2. GBR- guided bone regeneration
   - cadaver or pt. bone mixed together and putting membrane on it
   - adding volume
3. ridge split
   - can do this if have VOLUME ALREADY

Question 2

patient evaluation

Answer 2

importance of the dental or medical history

anything medical / patient factors that may not be aware of / contra-indications for various treatments

Question 3

bone grafts are driven?

Answer 3

PROSTHETICALLY

have plan in mind first - restoration planned and deign and then determine if you need this

Question 4

3 main grafing used in implant surgery

Answer 4

1. soft tissue grafting
2. bone augmentation
3. sinus lift

Question 5

stages of soft and hard tissue management

Answer 5

varies
- like may need to do soft tissue graft before bone tissue

soft tissue can be at multiple stages

hard tissue augmentation – 2 options – before or at time of placement

Question 6

timing of hard tissue augmentation / bone graft

Answer 6

1. BEFORE placement
2. during

predictability of doing it once patient has the restoration is variable

Question 7

height or width - harder to augment?

Answer 7

HEIGHT

width - easier

hardest when do not have height or width

vertical augmentation – do need to do it?? because risk of failure is higher

Question 8

local risk factors for grafting

Answer 8

1. previous history of graft failure
2. scaring in the area of grafting
3. frenums in the area to be grafted
   - Pulls tissue and can open
4. volume and direction of grafting needed
5. size/ span of defect

Question 9

implication of scaring in area of graft

Answer 9

NO BLOOD SUPPLY AND WE NEED BLOOD SUPPLY FORO HEALING

Question 10

soft and hard tissue augmentation go

Answer 10

hand in hand

- sometimes need one before the other and vise versa

Question 11

hard area to restore with grafts

Answer 11

unilateral esthetici zone like 7 and 8 and not having to do 9 and 10

easier to do 7-11 vs the two

Question 12

non vascularized bone grafts heal?

Answer 12

through a sequence of events
- grafts usually undergo partial necrosis - osteocytes death

followed by an inflammatory stage – existing bone is replaced with new bone by osteoblasts brought in by invading vessels

“creeping subsitution” -the slow process of vessel invasion and bony replcemetn

Question 13

creeping subsitution”

Answer 13

in bone graft healing – the slow process of vessel invasion and bony replacement

bone that forms is of the origin (like bone graft with hip in maxilla will become maxillary bone)

Question 14

all bone grafts we do for dental are

Answer 14

NON-vascularized

Question 15

bone graft physiology

Answer 15

1. clot / hematoma foramtion
2. process of inflamamtion
3. revascularization
4. osteoconduction
5. osteoinduciton
6. osteogenesis
7. remodeling

Question 16

rate of revascularization in cancellous bone?

Answer 16

faster – b/c more architecture

occurs RAPIDLY AND COMPLETELY due to its open architecture that allows easy invasion of blood vessels

Question 17

revascularization of cortical bone

Answer 17

SLOW AND INCOMPLETELY

• due to its dense lamellar structure
• vessels must penetrate along haversian and volkmann’s canal

remodels less

Question 18

inlay vs onlay

Answer 18

inlay – inside bone

onlay - on top of bone

• so depending on vessels coming from beneath vs coming from within and around in inlay
• need the vascularization

INTERPOSITION/ INLAY – maintained violume and preserved significantly better than onlay grafts

Question 19

interpiosition graft aka

Answer 19

inlay

Question 20

BEST GRAFTING MATERIAL

Answer 20

EMBRIOLOGIC ORIGIN
- from the skull

• gets remodeled less

Question 21

rigid fixation

Answer 21

use of rigid fixation in fracture repair results in primary bone healing

the effect of rigid fixation on bone grafts results in bone graft survival, greater bony union, increased primary bone healing and rapid re-vascularization by virtue of graft IMMOBILITY

dont want graft to move
- if have movement - wont get the re-vascularization and may get fibrous tissue in area / scarring- not good

Question 22

graft orientation

Answer 22

cancellous – against bone

bone grafts had better survival when their cancelloous surfaces contacted the bone even though grafts with cancellous surfaces facing soft tissue revascularized sooner

cortical - against the periosteium

Question 23

recipient site

Answer 23

grafts placed in avascular bed do NOT survivie well

other factors at the recipient site include prior irridation, infection, and tissue scarring

Question 24

best grafts are

Answer 24

from head and mixture of cancellous and cortical

cancellous –> revascularization

cortical –> to resist resorption

Question 25

sites block grafts often taken from

Answer 25

1. chin 2. ramus 3. body of mandible 4. hip 5. calvarium - best option - used more for trauma

Question 26

hip vs chin and ramus

Answer 26

we get more volume from the hip

Question 27

technique often used

Answer 27

uses ultra-sonic and chisel

Question 28

most comfortable (for patient) area to take bone from

Answer 28

ramus | - can take and cut into multiple pieces

Question 29

fixate the bone grafts with

Answer 29

screws - score it and primary closure

Question 30

rigid fixation for

Answer 30

vascularization -- idealy 2 screws

Question 31

4 maor things need for bone graft

Answer 31

1. rigid fixation 2. good adaption of the graft - one of the most important things -- may need to shave recipient side or the graft 3. passive soft tissue closure 4. 4-6 months of healing - want remodeling to occur - before place implant

Question 32

soft tissue closure?

Answer 32

need to SCORE the periosteum to allow soft tissue to expand

Question 33

graft blood upply dependent on

Answer 33

vascularization from the recipient side

Question 34

ridge split - general

Answer 34

taking the bone we have and making it WIDER use of an ultra-sonic machine to make cuts - use chisel to lift up a little and spread it apart

Question 35

____ needs to be longer than what your splitting with ridge split

Answer 35

IMPLANT FOR PRIMARY STABILITY works because bone is wider at bottom and opposite with the implant need the width of bone where you place the implant

Question 36

Guided bone regeneration

Answer 36

membrane to exlcude soft tissue from going in healing is coming from the bone underneath the membrane

Question 37

most predictable cases when doing guided bone regeneration

Answer 37

when there is adjacent bone around so works well when have 3 wall defect (not as well when 1 wall defect)

Question 38

when have 3 wall defect use?

Answer 38

guided bone regeneration healing starts from those walls! most remodeling occurs on buccal because thinner

Question 39

healing of guided regeneration

Answer 39

same allow about 6 months healing from bone within membrane excludes the periosteum

Question 40

approaches to sinus augmentation

Answer 40

1. crestal approach | 2. lateral window approach

Question 41

prerequisite for one stage implant placement and sinus lift

Answer 41

4-5 mm of bone HEIGHT

Question 42

external sinus lift healing?

Answer 42

6-9 months then implant placement

Question 43

if have less than 5 mm (residual height of bone) of bone height and sinus lift?

Answer 43

have to do external sinus lift - wait 6-9 months then implant placement

Question 44

options if residual bone height is greater than 5 mm with sinus lift / external sinus lift

Answer 44

1. simultaneous / immediate implant placement with sinus lift 2. external sinus lift - wait 6-9 months for healing - implant placementn