Week 4 Tulio- Implant Physiology Flashcards
How does smoking impair healing?
- Reduced O2
- Angiogenesis is affected (blood vessels reduced)
- Deprivation of nutrients
Are implants completely covered by bone?
No, only maximum 65% by bone. Rest is covered by fibrous tissue
How can you measure quality of bone?
- CBCT
- When you drill can tell how soft/hard it is by how much resistance there is (D1-D4 classification)
How does quality of bone impact implant abutment placement?
- When bone quality is high you can place abutment after 1 week
- If when you drill, bone is soft wait a few months for bone remodeling until placing abutment
What is required distance between implant and neighbouring tooth?
At least 1.5mm- otherwise no vasculature
Should there be mobility in implant? What is it likely to be if mobile?
No- should not be any micromovements (essentially ankylosed). Could be loose crown component or failed implant
Describe importance of crown length to implant ratio?
- Excessive crown length to implant ratio reduces resistance to occlusal forces
- Don’t use 6mm implant to replace 20mm crown
What are the 3 different connectors for implants?
- External hexagon
- Morse taper
- Internal hexagon
How does thickness of mucosa impact implant placement?
- Thicker mucosa (4mm)- can place implant at level of bone (crestal placement)
- Less mucosa- need to place implant deeper
How long does it take for complete bone healing?
+6months
Why avoid class I cantilevers?
Too much force on implant. Avoid distal cantilevers (esp molar area)
What is osteoinduction vs osteoconduction?
- Osteoinduction: undifferentiated cells are stimulated to develop into bone forming cell lineage
- Osteoconductive surface: permits bone growth on surface
What is intramembranous ossification and endochondral ossification?
- Intramembranous ossification: direct conversion of mesenchymal tissue into bone (bones of skull)
- Endochondral ossification: mesenchymal cells differentiate into cartilage and is later replaced by bone
What happens when you insert implant?
- Implant inserted
- Release of inflammatory cytokines
- Clot forms which is filled with fribrin
- Fibrin forms network to allow migration of cells toward implant surface (different implant materials react differently)
- Undifferentiated cells become osteoblast like cells and form first layer of highly mineralised cement and then bone on implant surface
What do we use as material for implant screw?
Titanium alloy (not pure titanium)
What systemic factors can affect healing process of implants?
- Diabetes
- Smoking
What happens if fibrin clot is not in contact with surface of implant?
Bone won’t be formed on surface of implant- instead there will be fibro-osseointegration.
What do bone cells come from?
Mesenchymal stromal cells
What is immediate loading?
Placing abutment on the same day-1 week after implant placement
Where is poorest bone quality?
Near maxillary tuberosity
What is the purpose of surgical stent?
Used to position dental implants to ensure that the implant is placed in the most ideal location, angulation and depth into the bone
What are the components of implant?
- Crown
- Abutment
- Screw
- Fixture/implant
Why is detailed records of implant and prosthetic components?
So you know exactly the brand and type of implant components are used so the tools used are compatible if patient comes back
Why does thickness of mucosa impact implant placement?
Need to make sure biological width isn’t encroached. There will be bone loss otherwise
Why does thickness of mucosa impact implant placement?
Need to make sure biological width isn’t encroached. There will be bone loss otherwise
What can you do if patient has relatively stable bone but not stable enough for immediate laoding?
Can place healing abutment to allow soft tissue to remodel around this. Won’t need to incise soft tissue later on and can just screw crown abutment on one osteointegration is achieved
