Osseous Regeneration

Question 1

When would you look to do surgery?

Answer 1

Pockets still severe (5mm or more) after SRP at recall

Question 2

What is GTR?

Answer 2

Guided Tissue regeneration — allow the repopulation of periodontal defects by cells capable of forming new connective tissue attachment and bone

Question 3

What are the guiding principles of GTR?

Answer 3

1. Exclude unwanted (Gingival epithelium and CT)
2. Protect the wanted (bone and PDL)
3. Hold the space

Question 4

What are the four criteria for the success of GTR?

Answer 4

1. Primary closure of soft tissue
2. Secluded space maintenance
3. Membrane stabilization
4. Adequate healing period

Question 5

What is the adequate healing period for GTR?

Answer 5

Do not probe for 3 months

Question 6

What are the qualities of an ideal membrane?

Answer 6

1. Absorbable
2. Bio compatible
3. Cell occlusive
4. Space maintenance
5. Tissue integration
6. Clinically manageable

Question 7

T/F: ePTFE is a resorbable membrane material.

Answer 7

False

non-resorbable

Question 8

What are the three types of membranes?

Answer 8

1. Non-resorbable (ePTFE)
2. Resorbable
3. Stem cells, functionally graded membranes

Question 9

T/F: Membrane resorption is predictable from person-person.

Answer 9

False

Question 10

T/F: The pore size of the membrane should be smaller than the size of epithelial cells.

Answer 10

True

Should not let epithelial cells invade the area you want attachment to form

Question 11

When should ePTFE be removed?

Answer 11

4-6 weeks post-op

Question 12

T/F: Most PLA/PGA membranes will degrade in 4-6 weeks.

Answer 12

True

Question 13

Why is it important for patients to know the source of the collagen membrane used?

Answer 13

Some are from pig or cow — may present an ethical issue to the patient

Question 14

What is the point of tenting screws and titanium sheets on membranes?

Answer 14

Create a scaffold so the membrane does not collapse the new bone — holds the space

Question 15

What are the three mechanisms by which grafts integrate?

Answer 15

1. Osteogenesis — viable cells
2. Osteoinduction — uncommitted CT cells induced
3. Osteoconduction — non viable scaffold

Question 16

What is an autograft? What properties does it have?

Answer 16

Taken from same patient and used immediately

Conductive, inductive, and genic

Question 17

An __________ is from another human donor.

Answer 17

Allograft

Question 18

Which of the three types of grafts are osteogenic?

Answer 18

Autograft only

Question 19

____________ are synthetic graft materials, and ___________ are from a different species.

Answer 19

Alloplast; xenograft

Both have osteoconductive properties only

Question 20

What are the disadvantages of autograft?

Answer 20

Second surgical site, insufficient material

Question 21

What are the advantages and disadvantages of allografts?

Answer 21

Advantages: availability, no donor site, fewer complications

Dis: no antigenicity, longer healing, less volume

Question 22

What is one of the biggest problems with allografts?

Answer 22

You have to overpack, it will rarely fill the whole defect

Question 23

______________ can sometimes be added with the graft to help it along.

Answer 23

Biological mediators (enamel matrix proteins, rhBMP)

Question 24

What type of incisions are made for GTR?

Answer 24

Always sulcular incisions — want to keep maximum amount of tissue

Question 25

T/F: The membrane gets its own suture independent of the flap.

Answer 25

True

Suture the membrane -> suture the flap over it

Question 26

What is emdogain and GEM 21S?

Answer 26

Both types of fillers to hold the space under the membrane to promote attachment gain

Question 27

What are the three keys to GTR?

Answer 27

1. Space maintainer — bone, retenting screw, reinforced membrane
2. Exclude epithelium
3. Protect and promote PDL growth