Pre Prosthetic Bone Graft

Question 1

When may pre-implant surgery be required?

Answer 1

Too little bone to support implant

Too much bone

Question 2

When is ridge reduction used?

Answer 2

Bone of poor quality
Need additional restorative space
Remove knife edge ridge

Question 3

Different types of augmentation?

Answer 3

Autograft - bone taken elsewhere on pt
Allograft - bone taken another person
Xenograft - bone from animal
Inorganic material

Question 4

What is osseoinductive?

Answer 4

Promotes bone formation

Question 5

What is osseoconductive?

Answer 5

A scaffold is placed - something else needed induce bone formation

Question 6

Example osseoinductive and osseoconductive materials?

Answer 6

Inductive - bone chips taken from pt

Conductive - bovine chips

Question 7

What techniques can be used to alter width of bone?

Answer 7

Guided bone regeneration
Ridge split
Block graft
Use appropriate implant e.g narrow/ angled

Question 8

What techniques can be used to alter height of bone?

Answer 8

Onlay graft
Inlay graft
Osseodistraction

Question 9

What can be good choice of implant if inadequate bone height?

Answer 9

Short implants

Zygomatic implants

Question 10

Give example of when can have reduced bone width?

Answer 10

Buccal bone resorption following loss of central incisor

Question 11

General principles of bone width surgery?

Answer 11

Plan - diagnostic wax up and stents
Evaluate and stimulate graft site
Fix graft
3-6 month - intergration of graft material

Question 12

What can be used if only a small difference to bone width is needed?

Answer 12

Guided bone regeneration - 50% implants have GBR

Question 13

Adv of GBR?

Answer 13

Can be done simultaneously w/ implant and in general practice

Question 14

What is GBR?

Answer 14

Missing bone replaced w/ particulate and collagen membrane - acts by tricking bone into thinking fractured

Question 15

How to bone chips osseoinduce?

Answer 15

Have high surface area which intorduce osteoblasts and proteins

Question 16

What is natural healing process following GBR?

Answer 16

Fracture initially form haematoma
Cause release inflammatory mediators - IL1/2 (interleukin)
Bone morphogenic proteins and cytokines induce bone formation

Question 17

What is dual layer GBR?

Answer 17

Flap raised expose thin bone - bur holes next to implant
Initial layer of bone chips placed over exposed threads of implants
Second layer bovine particulates placed

Question 18

Aim of dual layer GBR?

Answer 18

Bone chips are conductive

Then absorption of bone-conditioned blood makes bone substitute oseoinductive

Question 19

Why need membrane in GBR>

Answer 19

Prevent soft tissue contacting and resorbing graft material

Question 20

What is alternative to GBR?

Answer 20

Split ridge

Question 21

What to do when need place moderate-large amount bone?

Answer 21

Graft e.g buccal onlay graft

Question 22

What is a modern bone graft technique?

Answer 22

Use ramus of mandible or symphysis to graft bone

Question 23

Complication of symphysis grafts?

Answer 23

Reduced sensation
Scaring in buccal sulcus
Chin ptosis
Damage incisor/ canine roots

Question 24

Where can bone be taken if large amounts needed?

Answer 24

Iliac crest

Question 25

Problem w/ graft from iliac crest?

Answer 25

Quality of bone poorer than from mandible

Question 26

What technique can be used if inadequate height?

Answer 26

Occlusal onlay graft

Question 27

What technique can be used for localised defect?

Answer 27

Osseodistraction

Question 28

What is alternative to grafting?

Answer 28

all on 4

zygomatic implants

Question 29

What is ‘all on 4’?

Answer 29

Placing implant on angle posterior to avoid structures

Question 30

When are zygomatic implants used?

Answer 30

When no posterior bone is available