Regeneration/ Reconstruction & Khoury CH 11 Flashcards by Emily Sexton

What is the type of grafting material that has been shown to have the most gain in zero wall defects?

Autograft- Iliac bone and marrow have the most osteogenic and regenerative potential

How well did you know this?

Not at all

Perfectly

How does decalcification in DFDBA promote maximum osteoinduction

a. only 2% or less residual calcium

b. Demineralization of FDBA will make BMP accessible

How well did you know this?

Not at all

Perfectly

What is the Osteogenic potential between cancellous and cortical bone?

a. Cortical = little osteogenic potential

b. Cancellous bone – contains hematopoietic marrow provides better osteogenic potential

How well did you know this?

Not at all

Perfectly

Calcium Sulfate–> How is it resorbed when used as a regenerative membrane?

Giant cell reaction

How well did you know this?

Not at all

Perfectly

What are the advantages of Resorbable membranes?

More tissue compatible
Timing of resorption can be regulated by the amount of cross-linkage
No second surgery

How well did you know this?

Not at all

Perfectly

Which BMP is the primary Osteoinductive protein?

BMP - 2

How well did you know this?

Not at all

Perfectly

How does biogide degrade?

Collagenases and subsequently by gelatinases and peptidase

Biogide is a PORCINE resorbable membrane

How well did you know this?

Not at all

Perfectly

What are collagen membranes made from?

a. Porcine or bovine

b. Either Type I collagen or a combination of Type I and Type III

How well did you know this?

Not at all

Perfectly

What determines is a wound Regenerates vs Repair?

Cell type that repopulates

Regeneration = mesenchymal cells from the PDL or perivascular region of bone

How well did you know this?

Not at all

Perfectly

How do you most accurately assess regeneration?

Histology

*Radiographs (standardized)

How well did you know this?

Not at all

Perfectly

What does dense HA most likely heal with, histologically?

a. HA is an anorganic Alloplast (Ceramic)

b. Healing occurs through fibrous encapsulation of the HA particles in the intraosseous defect
c. Long Junctional Epithelium and CT attachment
d. Does NOT induce new attachment or bone formation

How well did you know this?

Not at all

Perfectly

What are Competence and Progression Factors?

Competence:

a. Prime the cell to enter the cell proliferation cycle
b. PDGF (Platelet derived growth factor)

Progression:

a. Required for cell division
b. IGF-1

How well did you know this?

Not at all

Perfectly

What is regeneration?

A. Formation of new bone
B. Cementum
C. Functionally oriented PDL

How well did you know this?

Not at all

Perfectly

What is reattachment?

Non-diseased site

How well did you know this?

Not at all

Perfectly

What is repair

a. “non-functional types of scar tissue” or new attachment
i. Long Junctional Epithelium
ii. New CT attachment
iii. Ankylosis

How well did you know this?

Not at all

Perfectly

What is a root conditioner?

a. Remove smear layer from root surface to expose collagen fibers and opened dentinal tubules.
b. Citric acid: (pH 2-3)
c. Tetracycline and EDTA:

How well did you know this?

Not at all

Perfectly

What is osteogenic?

What determines Osteogenic Potential?

a. Has vital cells in the graft
b. Capable of producing new bone

autograft
Osteogenic Potential–> Amount of cancellous bone

How well did you know this?

Not at all

Perfectly

What is osteoinductive

a. Induces bone formation by recruiting undifferentiated mesenchymal cells, is mitogenic for pre-osteoblasts, and induces differentiation of these cells into bone forming osteoblasts)

Examples:

b. FDBA
c. DFDBA ( demineralization of cortical bone allograft     exposed BMP

How well did you know this?

Not at all

Perfectly

What is osteoconductive?

a. Acts as scaffold
b. Chemically treated to remove organic components to leave trabecular and porous scaffolding for new bone formation

Example: Xenograft

What is a xenograft

Different species
Scaffold
Osteoconductive

**Longest graft type to resorb

What is alloplast

Inorganic material (synthetic)

What is Guided Tissue Regeneration?

A barrier membrane allowing formation of new periodontium

What are the available membrane types

Resorbable

Non Resorbable

Positives of Non- Resorbable membrane?

a. Space maintenance
b. Clot Protection
c. Barrier Formation—especially in large defects

Negatives of non resorbable membrane?

1. 2nd surgery needed | 2. Frequent exposure to the oral cavity which leads to failed osseous reconstruction

Positives of Resorbable membrane?

i. More tissue compatible ii. No 2nd surgery required iii. Variable times of resorption REPEAT QUESTION

Negatives of resorbable membrane?

Lack of rigidity/ Tight scaffold

Discuss emdogain

a. It is OSTEOPROMOTIVE b. True regeneration is possible c. Harvested from developing porcine teeth, contains a protein preparation that mimics the matrix proteins that induce cementogenesis

Discuss PDGF

Platelet derived growth factor a. mitogenic and chemotactic factor for mesenchymal cells b. Type of Competence factor

What are BMPs?

a. Regulatory glycoproteins that are members of the TGF-beta superfamily, and they stimulate mesenchymal stem cells to differentiate into chondroblasts and osteoblasts. (Cartilage and Bone) Risk of ankylosis

What are some thing that influence the success of regeneration? (4)

i. Plaque control/compliance ii. Smoking iii. Tooth/defect factors iv. Characteristics of defects - depth, width, # of walls

How do resorbable membranes break down?

Resorption | Krebs Cycle

What is the ideal material for ridge preservation?

Osetoconductive a. Needs to be a scaffold for new bone formation but also minimal in volume at implant placement

What is the point of Decortication, is it worth it?

a. Purpose is to open marrow spaces and allow osteoprogenitor cells to migrate to the site

What factors affect bone graft Osteoinductive potential

Age of Donor

Why does regeneration fail? (3)

1. Mechanical Instability 2. Poor blood supply 3. Competing tissue

When do you graft and bolt?

Ridge < 4 mm wide and you need primary stability

Why do you get early membrane exposure?

1. Not using aseptic techniques 2. No passive closure 3. Inadequate flap mobility 4. Smoking 5. Diabetes 6. Pressure from prosthesis 7. Shallow vestibule

What bacteria colonize exposed membranes?

1. P Gingivalis | 2. Aa

How much Bone resorption of the ridge following tooth extraction?

40-60% horizontal resorption in 3-12 months

What is PASS

Primary closure Angiogenesis Space Maintenance Stability

What is the gain in a ridge split (Distraction Osteogenesis)?

3.5 mm

Ignore this question-- wasn't in our lecture How long auto/allograft block grafts last?

3/12 Not sure what this means

How much vertical bone can you gain with a block graft?

3 - 5 mm

How do you obtain vertical augmentation?

Onlay block graft Distraction Ortho Extrusion