Gingiva & Peri-Implant Tissues

Question 1

What are the three parts of an implant?

Answer 1

Fixture

Abutment

Crown/denture

Question 2

What is osteointegration?

Answer 2

Formation of bone around fixture to create a strong bond

Question 3

What are the three types of denture attachments?

Answer 3

Ball

Magnet

Bar

Question 4

Why is a magnet denture attachment not good?

Answer 4

Corrodes in saliva

Question 5

Why is a bar denture attachment not good?

Answer 5

Hard to clean

Question 6

What is an external connection?

Answer 6

Screwed on and crown cannot rotate

Question 7

What is an internal connection?

Answer 7

Crown sits within implant

Question 8

What does the periodontium consist of?

Answer 8

Gingiva

PDL

Cementum

Alveolar bone

Question 9

What is the periodontium?

Answer 9

Supporting structures of the tooth

Question 10

What does the peri-implant structure consist of?

Answer 10

Peri-implant mucosa

Alveolar bone

Question 11

What are the four epithelial layers of the gingiva?

Answer 11

Stratum basale

Stratum spinosum

Stratum granulosum

Stratum corneum

Question 12

How thick is the epithelial layer of the gingiva?

Answer 12

0.2-0.3mm

Question 13

What types of gingival keratinisation are there?

Answer 13

Orthokeratinised

Parakeratinised

Incomplete keratinisation

Question 14

What defines the gingiva?

Answer 14

Cervical margin and mucogingival junction

Question 15

Describe the gingiva.

Answer 15

Part of oral mucosa

Hard and bound to teeth

Question 16

What are the two ways to divide the gingiva and what are the subgroups?

Answer 16

Position - attached, free, crevicular and junctional

Structures - epithelial elements and connective tissue elements

Question 17

What is the width of the supracrestal tissue attachment?

Answer 17

2mm

Question 18

What two regions make up the supracrestal tissue attachment?

Answer 18

Connective tissue attachment

Junctional epithelium

Question 19

What happens to the supracrestal tissue attachment when you drill away some of the junctional epithelium?

Answer 19

Stays the same as bone is resorbed coronally

Question 20

Describe the attached gingiva.

Answer 20

Pale pink, keratinised mucosa

May be stippled in health

Firm and tightly-bound onto bone

Question 21

Where is the attached gingiva located?

Answer 21

From mucogingival junction to free gingival groove

Question 22

Describe the free gingiva.

Answer 22

Pale pink, keratinised mucosa

Slightly loose and smooth

Question 23

Where is the free gingiva located?

Answer 23

Free gingival groove to cervical margin

Question 24

What is the papilla?

Answer 24

Interdental gingival tissue

Question 25

What is the shape of the anterior papillae?

Answer 25

Pyramidal

Question 26

What is the shape of the posterior papillae?

Answer 26

COL - tent-shaped

Question 27

What cells are found in the gingival epithelium? (5)

Answer 27

Keratinocytes Melanocytes Langerhan's cells Merkel cells Some T-cells

Question 28

Where are the Langerhan's cells found and what do they do?

Answer 28

Most coronal part of junctional epithelium Antigen-presenting cells

Question 29

Where are the Merkel cells located and what do they do?

Answer 29

Stratum basale Sensory touch receptors

Question 30

Is the crevicular epithelium keratinised?

Answer 30

No

Question 31

What cell types are found in the junctional epithelium and why?

Answer 31

Basal and suprabasal cells Rapid turnover so insufficient time to differentiate

Question 32

What is the rate of turnover of the junctional epithelium?

Answer 32

10-14 days

Question 33

Why is the junctional epithelium permeable?

Answer 33

Large intercellular spaces

Question 34

What are four characteristics of the junctional epithelium?

Answer 34

Non-keratinised Large intercellular spaces (permeable) Rapid turnover Hemidesmosomes

Question 35

What attaches the junctional epithelium to the enamel?

Answer 35

Hemidesmosomes to protein layer/extended basal lamina on enamel surface

Question 36

What is the range of thickness of the junctional epithelium?

Answer 36

3-30 cells thick

Question 37

What are the differences between probing healthy and inflamed junctional epithelium?

Answer 37

Healthy - stops in JE (0.7mm), not deep, no bleeding Inflamed - ulcerated so stops in inflamed connective tissue, bleeding, more tender

Question 38

Which implant materials form a junctional epithelium?

Answer 38

Titanium Zirconium Aluminium

Question 39

What are the dimensions of a stable biological seal?

Answer 39

3mm supracrestal soft tissue attachment: 1mm connective tissue 2mm junctional epithelium

Question 40

Why is a probe likely to enter the connective tissue around an implant?

Answer 40

Weaker seal than natural tooth

Question 41

What is the inflammatory barrier?

Answer 41

Stable gingivitis-like lesion in health

Question 42

What could be controlling epithelial downgrowth?

Answer 42

Granulation tissue/underlying connective tissue Signals from deeper tissues

Question 43

What does the gingival connective tissue contain? (7)

Answer 43

GAGs and fluid Collagen I and III fibres in a strong, organised network Elastic fibres Fibroblasts Blood vessels Lymph vessels Nerves

Question 44

What percentage of the normal gingival connective tissue volume is collagen?

Answer 44

50-60%

Question 45

How is the collagen network of gingival connective tissue different with an implant?

Answer 45

Fibres are differently orientated No dentogingival fibres present Scar tissue-like

Question 46

What are the 4 types of collagen fibres present in gingival connective tissue?

Answer 46

Dentogingival Alveolar crest Dentoalveolar Circular

Question 47

Compare the two zones of the gingival connective tissue around an implant.

Answer 47

Inner - fibre-rich (87% collagen), few cells and vessels, lots of circular fibres Outer - multidirectional fibres, less collagen (63%), more cells and vessels

Question 48

How thick is the inner zone of the gingival connective tissue around an implant?

Answer 48

50-100um

Question 49

When are the blood vessels in the gingival connective tissue constricted?

Answer 49

No infection Smoking

Question 50

Where does the main blood supply for peri-implant tissue come from?

Answer 50

Supra-alveolar connective tissue

Question 51

Why does the peri-implant tissue have less of an inflammatory response than gingival connective tissue?

Answer 51

Less blood flow

Question 52

Where is the crest of the bone in healthy teeth?

Answer 52

1-2mm apical to cementoenamel junction

Question 53

Why is it dangerous that there are no ligament receptors with implants?

Answer 53

No jaw-opening reflex so could break other teeth