implant planning and placement

Question 1

What is osseointegration?

Answer 1

A direct functional and structural connection between a load bearing dental implant and living (organised) bone

Question 2

What are the 2 stages of osseointegration?

Answer 2

Primary osseointegration - implant is anchored in bone due to frictional forces provided between osteotomy and dental implant design features
Secondary osseointegration - the process of a functional connection between bone and a dental implant. Living bone grows onto the surface of a dental implant

Question 3

What are the differences between tooth supra-crestal soft tissue and implant supra-crestal soft tissue?

Answer 3

Tooth - more fibroblasts, less collagen and collagen fibers are orientated perpendicular to the root surface
Implant - more collagen, less fibroblasts, collagen fibers are orientated parallel to the implant crown

Question 4

What are the differences between tooth sub-crestal tissue and implant sub-crestal tissue?

Answer 4

Tooth - anchored to bone by periodontal complex, capable of physiological adaptation and resilient tissue attachment
implant - anchored to bone by direct functional contact, no physiological adaption present, a rigid connection

Question 5

What different materials can be used for implants?

Answer 5

Titanium - pure type 4 Ti
Titanium Zirconium (Ti-Zi)
Ceramic implant - yittra stabilised zirconia (Y-TZP)

Question 6

When may a tapered implant design be used and why?

Answer 6

Where there is root convergence apically
May provide increased primary stability in immediate placement

Question 7

What dictates the lengths and diameters of implants?

Answer 7

Site
Indication
Local anatomy

Question 8

What size and diameter of implants have the best success rate?

Answer 8

Narrow diameter
Short (<10mm) implants

Question 9

What are the different machine (turned) surface treatments of implants?

Answer 9

Smooth - 0-0.5um
Mild - 0.5-1um
Moderately - 1-2um
Rough - >2um

Question 10

What different surface treatments can be applied to implants?

Answer 10

Sandblasting
Acid etch
Plasma spray

Question 11

What is the purpose of an implant?

Answer 11

To replace missing teeth functionally, aesthetically and physiologically

Question 12

Name 4 medical conditions/drugs that can affect implant success

Answer 12

Any from:
SSRIs - bruxism
PPIs
Bisphosphonates
Poorly controlled diabetes
Cardiovascular disease
Steroids
Radiotherapy

Question 13

How does smoking dose affect implant success?

Answer 13

<10 daily is medium risk
>10 daily is high risk

Question 14

What is important in DH during implant planning?

Answer 14

Patient attendance
Motivation
Previous treatment - is pt suitable for surgical procedure
Is the pt a bruxist

Question 15

What are the risks of implant placement in someone who is not skeletally mature?

Answer 15

Relative infra-occlusion
Suboptimal aesthetics
Occlusal disharmony
Implant fenestration

Question 16

What are the different gingival biotypes and how is this discerned?

Answer 16

Thick flat
Thick scalloped
Thin scalloped
Differentiated through probe visibility

Question 17

What determines the presence of adjacent papilla in implants?

Answer 17

The distance from the bone crest to the adjacent contact point

Question 18

What local anatomy in the maxilla is important during implant planning?

Answer 18

Maxillary sinus
Nasal floor
Naso-palatine canal
Infra-orbital nerve

Question 19

What local anatomy in the mandible is important during implant planning?

Answer 19

Inferior alveolar canal
Mental foramen
Incisive canal
Lingual perforating vessels
Submandibular fossa

Question 20

What positions do you need to consider for 3D implant positioning?

Answer 20

Mesio-distal positioning and orientation
Buccal-palatal positioning and orientation
Apico-coronal positioning

Question 21

What does 3D implant positioning depend on?

Answer 21

Implant system being used
Proposed gingival margin
Local anatomy
Prosthetic plan (cement retained vs screw retained)

Question 22

How much mesio-distal distance is needed between an implant and adjacent teeth and why is this?

Answer 22

Minimum of 1.5mm
Lowers risk of damage to adjacent teeth
Lowers risk of bone necrosis and soft tissue defects

Question 23

How much buccal-palatal tissue is needed outside of the implant?

Answer 23

> 1mm of bone labially or >2mm hard/soft tissue

Question 24

When should you consider guided bone regeneration (GBR)?

Answer 24

Dehiscence - bone defect towards the marginal bone
Fennestration - bony coverage of root surface is lost
If inadequate contour

Question 25

What are the different types of placement protocol for implants?

Answer 25

Type 1 - immediate implant placement
Type 2 - early implant placement with soft tissue healing
Type 3 - early implant placement with partial bone healing
Type 4 - late implant placement in healed sites

Question 26

What are the healing durations for the different implant placement protocols?

Answer 26

Type 2 - 4-6 weeks
Type 3 - 12-16 weeks
Type 4 - 6 months or more

Question 27

Name 4 planning aids commonly used in implant planning?

Answer 27

Any from:
- study models
- diagnostic wax ups
- surgical template
- provisonal essex retainer
- clinical photographs
- CBCT
- surgical guide

Question 28

Describe analogue implant planning

Answer 28

Diagnostic wax ups used to plan size and position of implants
Combine this with CBCT
Can be transferred to mouth to show the pt the aim of tx
When agreeable, converted to stone and surgical template is made

Question 29

Describe digital implant planning

Answer 29

Software prosthetically and surgically plans implant placement
Allows identification of anatomical structures
Software highlights potential issues of spacing and orientation
Produces a surgical guide for implant placement