Implant Ridge Preservation

Question 1

What is ridge preservation?

Answer 1

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

Question 2

Why should we ridge preserve?

Answer 2

Enable implant installation and stability

Reduce loss of alveolar bone volume

Reduce need for additional bone grafting

Improve aesthetic and phonetic outcome

Question 3

What are the types of extraction sockets?

Answer 3

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

Question 4

What happens to bone sockets when a tooth is extracted?

Answer 4

30% loss of buccal plate

10% loss of lingual plate

20% loss of ridge height

2 - 2.5mm resorption of bone at 8 weeks

Question 5

What are the phases of post extraction changes?

Answer 5

Phase 1 =

Elimination / resorption of bundle bone

Loss of width and height.

Phase 2 =

Question 6

What is bundle bone?

Answer 6

Un-mature bone in which collagen fibrils insert into the tooth and are partially mineralised

Question 7

What is the fastest bone to go following extraction?

Answer 7

Bundle bone in the lamina dura.

Question 8

How does extraction technique affect implants?

Answer 8

Modifying extraction technique allows bone retention to be more easy. Should be considered when considering implant treatment.

Avoid using periotomes and mallet

Question 9

How is ridge preservation achieved?

Answer 9

Placing a bone substitute/graft at the time of extraction with the aim of minimising ridge dimensional changes

Question 10

What are the objectives of ridge preservation?

Answer 10

1) Wound care: Covers the wound, Protects from oral infection, Haemostasis

Preserve ridge volumes

Osteoneogenesis

Question 11

What materials are used for ridge preservation?

Answer 11

Xenogenic materials - bio - oss

Bone ceramic

Allograft-minerOss

Others (Auto & BMP)

BetaTCP-fortoss / bond bone

Question 12

Which bone substitutes most resemble human bone?

Answer 12

Geistlich bio-oss

Question 13

Which material is the best for use as a ridge preserver?

Answer 13

Depends on clinical scenario

Depends on how quickly you plan to place implant/restore the space

Depends on which materials are available

Question 14

What are the phases of ridge preservation treatment?

Answer 14

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)

Question 15

How does the bone heal following extraction?

Answer 15

Osteoinduction

Osteoconduction

Question 16

How does osteoinduction work?

Answer 16

It is the process that stimulates osteogenesis.

Undifferentiated mesenchymal cells are transformed into osteoblasts

Graft materials induce osteogenesis and bone formation.

Question 17

What hormone is essential for osteoinduction?

Answer 17

BMP

Question 18

How does osteoconduction work?

Answer 18

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.

Question 19

What material is placed over the bone?

Answer 19

Collagen matrix light - gelfoam, collacote

Collagen matrix durable

Soft tissue graft - Auto or allograft

Nonabsorbable matrix

Titanium membrane

Question 20

How can we decide whether or not to do a ridge preservation procedure?

Answer 20

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.