Osseous Regeneration Flashcards
What are the possible outcomes of therapy?
New attachment
Long Junctional Epithelium
Root resorption/ankylosis
New attachment
Ideal
New PDL, Cementum, and Alveolar Bone
Long Junctional Epithelium
Classic form of healing following SRP
Junctional epithelium forms
Root Resorption/Ankylosis
Bonne attaches to the tooth
Guided Tissue Regeneration Definition
Procedures allowing the repopulation of a periodontal defect by cells capable of forming new CT attachment and alveolar bone
“The Race to Repopulate”
If bone and PDL don’t grow back, you will get a clot, and epithelium will replace that clot, creating a pocket
Membranes
Can help with guided tissue regeneration
Prevents the epithelium from invading
How to place a membrane
We fill a site with bone, cover it with a membrane, and place a flap over it
It allows the CT to regenerate
What are the criteria for success of GTR?
Primary closure of soft tissue
Secluded space maintenance
Membrane stabilization
Adequate healing period
What are the qualities of an ideal membrane?
Absorbable Biocompatability Cell occlusive Space maintenance Tissue integration Clinically manegable
What is an example of a non-resorbable membrane
ePTFE
What are the advantages of ePTFE?
We know it won’t resorb, so we don’t rely on anything
There are many different configurations we can use
What are the disadvantages of ePTFE?
They come pre-cut, so we can’t customize
We have to do a second surgery
PLA/PGA membranes
Resorbable membrane
Polyactic acid and Citric Acid Ether
Degradation takes 4-6 weeks
One-stage surgery
Collagen membrane
Cross-linked
Adding Zinc to the membrane prevents the breakdown of collagen
-Zn provides more crosslinks making it more stable, leading to a slower break down
What are the different layers of functionally graded membranes
CL - Core layer
SL - surface layer
Core layer of functionally graded membrane
Made of protein
What are the two different surfaces of the Surface Layer of a functionally graded membrane
Epithelial SL - metronidazole incorporated; faces epithelium
Bone SL - HA incorporated; faces bone
How can we reinforce a membrane?
Creating a scaffold with screws and/or fillers
What are the different types of graft integrations?
Osteogenesis
Osteoinfuciton
Osteoconduction
Osteogeneis
Viable cells
Osteoinduciton
Uncommited CT cells get induced
Osteoconduction
Non-viable scaffold
Extremely passive
Autogenous graft
Cells from the same pt
Osteoconductive, osteoinductive, and osteogenic
What are the advantages of an autogenous graft?
‘Gold standard’ - predictable results
Osteogenic
What are the disadvantages of an autogenous graft?
Second surgery required
There’s a limit as to how much material we can use
Allograft
From a human source, but a different patient
Osteoconductive and can be osteoinductive
Allograft advantages
Avaliable
No second surgery required
Reduced surgical time
Fewer complicaitons
Allograft disadvantages
Anitigenicity
Longer healing
Les volume (only get about 70-80% of what we put in)
Alloplasts and Xenografts
Only osetoconductive
Can be from cows or somethign completely genetic
What type of incision is used in GTF?
Sulcular
Enamel Matrix Derivative (Emdogain)
Useful as an osteoinductive agent
Significantly improves attachment levels and reduces pockets
Emdogain Action (Enamel Matrix Derivative)
Forms a layer of ECM on the root surface that promotes selective cell colonization - it enhances the mesenchymal cell adhesion and inhibits epithelial cell adhesion
Human Platelet-Derived Growth Factor in Tri-Calcium Phosphate Action
PDGF stimulates migration and proliferation of osteoblasts, fibroblasts, and cementoblasts - leads to formation of new bone PDL, and cementum
Increases bone but no effect on attachment gain
Which sutures are used for GTR?
Have to be non-braided and non-resorbable:
PLA/PGA
Goretex
