Implant Ridge Preservation Flashcards
What is ridge preservation?
The application of biomaterials directly into the fresh extraction socket following tooth extraction.
Materials used vary from bone fillers and xenogenic grafts to allografts and alloplasts
Why should we ridge preserve?
Enable implant installation and stability
Reduce loss of alveolar bone volume
Reduce need for additional bone grafting
Improve aesthetic and phonetic outcome
What are the types of extraction sockets?
Type 1 = intact soft tissue and intact buccal plate
Type 2 = Intact soft tissue but part of the buccal plate is missing
Type 3 = Soft tissue and bone loss
What happens to bone sockets when a tooth is extracted?
30% loss of buccal plate
10% loss of lingual plate
20% loss of ridge height
2 - 2.5mm resorption of bone at 8 weeks
What are the phases of post extraction changes?
Phase 1 =
Elimination / resorption of bundle bone
Loss of width and height.
Phase 2 =
What is bundle bone?
Un-mature bone in which collagen fibrils insert into the tooth and are partially mineralised
What is the fastest bone to go following extraction?
Bundle bone in the lamina dura.
How does extraction technique affect implants?
Modifying extraction technique allows bone retention to be more easy. Should be considered when considering implant treatment.
Avoid using periotomes and mallet
How is ridge preservation achieved?
Placing a bone substitute/graft at the time of extraction with the aim of minimising ridge dimensional changes
What are the objectives of ridge preservation?
1) Wound care: Covers the wound, Protects from oral infection, Haemostasis
Preserve ridge volumes
Osteoneogenesis
What materials are used for ridge preservation?
Xenogenic materials - bio - oss
Bone ceramic
Allograft-minerOss
Others (Auto & BMP)
BetaTCP-fortoss / bond bone
Which bone substitutes most resemble human bone?
Geistlich bio-oss
Which material is the best for use as a ridge preserver?
Depends on clinical scenario
Depends on how quickly you plan to place implant/restore the space
Depends on which materials are available
What are the phases of ridge preservation treatment?
Tooth extraction phase (remove tooth)
Preparation phase (clean the edges of the socket with scalpel and high speed bur)
Filling phase (Squeeze collagen into the socket)
Closing phase (Suture the extraction socket shut)
How does the bone heal following extraction?
Osteoinduction
Osteoconduction
How does osteoinduction work?
It is the process that stimulates osteogenesis.
Undifferentiated mesenchymal cells are transformed into osteoblasts
Graft materials induce osteogenesis and bone formation.
What hormone is essential for osteoinduction?
BMP
How does osteoconduction work?
New bone is formed by a process called “creeping substitution”
Bone graft material is the scaffold to promote and allow vessels to develop in growth.
Bone formation by margin of host bone.
What material is placed over the bone?
Collagen matrix light - gelfoam, collacote
Collagen matrix durable
Soft tissue graft - Auto or allograft
Nonabsorbable matrix
Titanium membrane
How can we decide whether or not to do a ridge preservation procedure?
When placing within 8 weeks of extraction, measure the buccal plate if the buccal plate is greater than 1mm do nothing. Place early or immediately. If you are going to wait then ridge preserve.
If buccal plate is <1mm -> Ridge preserve -> Implant at 3 - 6 months
If absent buccal plate -> Ridge preserve with shape membrane. -> GBR or block graft.
