Implants

Question 1

Is bone continuous for osteointegration?

Answer 1

No. It is not continuous bone and has a proteoglycan layer at the interface about 20 nm thick.

Question 2

For osseointegration, is there a connective tissue connection to the implant?

Answer 2

Yes, there can be.

Question 3

For a natural tooth, what are the connections, tissues, biologic width, and probing depths?

Answer 3

Natural tooth:
Connection between bone, cementum, PDL

Connective tissue comprised of various fiber groups, and perpendicular attachment.

Biologic width = 2.04 mm

Probe depths =

Question 4

For an implant, what are the connections, tissues, biologic width, and probing depths?

Answer 4

Implant:
Connection from osseointegration

Connective tissue comprised of fewer fiber groups, and parallel attachment.

Biologic width = 2.95 mm

Probe depths = 2.5 - 5.0 mm

Question 5

What is the biologic width?

Answer 5

The width of periodontal ligament through the gingiva.

Question 6

Should you probe implants?

Answer 6

Yes! This can be the most important diagnostic.

Question 7

What are the two main ways to attach an implant?

Answer 7

Screw-retained or cemented.

Cemented can be difficult and cause perio-disease.

Question 8

What is fibrointegration and is it good or bad?

Answer 8

Bad! This means the implant has failed. There were possibly micromovements at the beginning, so it is therefore a mobile implant.

Question 9

Why does Titanium work so well as a biocompatible material?

Answer 9

The oxide layer! This layer is key. The TiO2 is a ceramic layer that is 3 - 5 nm thick and highly corrosion resistant.

Question 10

Do you want a smooth or rough fixture?

Answer 10

Rough is best and provides better healing.

Roughness allows fibrin linkage and initial healing and bone integration. The cells spread out well.

The exposed top is smooth to allow cleaning.

Question 11

Which is the most common method of “roughing” the fixture?

Answer 11

SLA is most common. “Sand-blasted, large grit, acid etched.”

Acid etched also exists (very rough) and machined (not rough enough).

Question 12

Name 4 implant designs:

Answer 12

1. Subperiosteal implant = not used anymore
2. Transosseous implant = old design, stapled into mandible.
3. Endosseus blade = old, if it fails there is major bone loss
4. Endosseous Root form implant = popular today

Question 13

Does gold integrate well for osseointegration?

Answer 13

Nope.

Question 14

Why have a threaded fixture?

Answer 14

Implants aren’t self-tapping! The threads are there for surface area and to distribute forces.

Question 15

What is the microgap?

Answer 15

A donut of inflammatory connective tissue infiltrate (neutrophils) that can result in bone loss.

Note: bone ALWAYS establishes below the microgap.

Question 16

Where does bone establish around the fixture?

Answer 16

Below the microgap at the rough-smooth border or in relationship to the microgap.

Question 17

Knowing that the microgap causes bone loss, what can be done?

Answer 17

Place the rough-smooth interface at a more apical gingival margin position…thus shifting the microgap higher.

Try to control the microgap

Question 18

What is Type I Bone? How are the bone hardnesses classified?

Answer 18

Type I = hard, like granite (anterior mandible)
Type IV = least dense (posterior maxilla)

Implants in type IV are less successful, but they are improving.

Question 19

What is a 2-stage implant?

Answer 19

Bone grafting is necessary and adds an additional step.

Question 20

Is past periodontal disease always a disqualifier?

Answer 20

No. If the tooth had attachment loss or bone loss, there was no correlation to bone loss around an implant.

Poor compliance is the most significant factor of implant loss.

“implant survival was comparable to periodontally healthy individuals if the disease was treated/maintained “

Question 21

Can the tooth that is to be replaced just be removed any which-way?

Answer 21

No, the buccal bone plate should be preserved, and should be about 2 mm thick.

Note that the immediate placement needs good bone!

Question 22

Why not just always reflect the gingiva?

Answer 22

In theory, if the gingiva is not reflected, there is better blood supply maintained to the bone.

Question 23

What is periimplant mucositis?

Answer 23

Chronic plaque-induced infection of the marginal periimplant soft tissues.

There is no resultant bone loss.

Pretty easy to treat early.

Question 24

What is peri-implantitis?

Answer 24

Inflammation that results in progressive loss of supporting bone.

Question 25

Can you move an implant with braces?

Answer 25

No. The implant is anchored in bone.

Question 26

What is the success criteria for an implant?

Answer 26

1.