2021

Question 1

Define the term ‘alveolar bone proper’ as the term relates to periodontal tissues
Describe the function, structure and radiographic features of this bone (4)

Answer 1

1. Alveolar bone proper is the thin lamella of bone which provides attachment for tooth via Sharpey’s fibres
2. It is perforated to allow ingress of nerves and blood vessels
3. Appears radiographically as lamina dura
4. Lends support to the tooth

Question 2

Outline 3 types of pathogenic synergy which contribute to periodontal disease (3)

Answer 2

Any 3 from:

1. Bacteria can signal each other
2. Bacteria can transfer genes
3. Synergy for co-adhesion
4. Production of ECM
5. Providing nutrients for each other
6. Provide attachment to the pellicle

Question 3

Name 1 periodontal pathogen that contributes to pathogenic synergy and state its role in this process (2)

Answer 3

P. gingivalis / F. nucleatum

F. nucleatum binds to plasminogen and P. gingivalis produces proteolytic enzymes which convert it into plasmin, to facilitate evasion of host defences

Question 4

Name 5 bacterial pathogens associated with periodontal disease (5)

Answer 4

1. Fusobacterium nucleatum
2. Porphyromonas gingivalis
3. Treponema denticola
4. Tanerella forsythia
5. Prevotella intermedia

Question 5

Outline the roles of RANK ligand and OPG in regulation of osteoclast activation (5)

Answer 5

1. RANK ligand (member of TNF superfamily) expressed on osteoblast surface
2. Receptor expressed on precursor for osteoclast cells
3. Once bound, stimulation of osteoclast activity as it induces differentiation
4. OPG secreted by osteoblasts and inhibits RANK ligand activity
5. Osteoclastogenic molecules stimulate expression of RANK ligand and blunt production of OPG

Question 6

List 4 antibacterial actions of saliva (4)

Answer 6

1. Inhibition of attachment of bacteria
2. Washing action
3. Kills bacteria by peroxidase system
4. Kills bacteria by lysozymes

Question 7

List 2 causes for xerostomia (2)

Answer 7

1. Drug induced (antihypertensives and antidepressants)

2. Head and neck radiation

Question 8

Describe the features of WHO probe (2)

Answer 8

1. Tapered probe with ball ended tip

2. Black band from 3.5 to 5.5mm

Question 9

Outline 3 uses for WHO probe (3)

Answer 9

1. Examine presence of plaque
2. Detection of sub-gingival plaque
3. Measure pocket depths

Question 10

Describe how stage of periodontal condition is determined (2)

Answer 10

1. Amount of interproximal bone loss at worst site as seen on radiograph
2. Measured from CEJ to root apex

Question 11

Describe how grade of periodontal condition is determined (2)

Answer 11

1. Ratio of bone loss to age at worst site

2. Calculated by dividing maximum bone loss by age

Question 12

List 6 factors which can increase plaque retention on teeth (6)

Answer 12

1. Sub-gingival calculus
2. Dentures
3. Xerostomia
4. Dental anomalies / Tooth angulation
5. Fixed appliances
6. Poor restoration margins

Question 13

Describe the Bass technique for toothbrushing (5)

Answer 13

1. Brush placed at 45 degrees to gingiva
2. Firm but light pressure, slightly under gum line
3. Use circular movements on each tooth, brushing all surfaces
4. Brush for 30 seconds in each quadrant
5. Brush tongue

Question 14

Name mechanism of action of 2 types of ultrasonic scalers (2)

Answer 14

1. Peizoelectric - Vibrations caused by oscillation of quartz to produce linear tip movement
2. Magnetostrictive - Vibrations caused by magnets to produce eliptical tip movement

Question 15

Name 3 mechanisms by which ultrasonic scalers can remove deposits from tooth surface (3)

Answer 15

1. Mechanical energy
2. Irrigation
3. Cavitation

Question 16

Describe the advantages and disadvantages of ultrasonic scalers compared to hand scalers (8)

Answer 16

Advantages

1. Less tiring for operator
2. Allow quick removal of large deposits
3. Used to remove overhanging margins on amalgam restorations
4. Clears away field of debris and blood through irrigation

Disadvantages

1. Cause sensitivity during and after procedure
2. Generates large amount of heat
3. Production of contaminated aerosols, which may obscure vision
4. Technique sensitive - Can cause damage

Question 17

List stages of management of contaminated sharps injury (7)

Answer 17

1. Stop procedure
2. Let wound bleed
3. Wash with soap and warm running water
4. Apply waterproof dressing
5. Report incident to supervisor immediately and inform patient
6. Sharps injury protocol - Risk assessment, and consent for blood tests
7. Occupational Health - Clean / Dirty need and whether patient has known BBV disease

Question 18

Define the term cross infection (2)

Answer 18

Transmission of pathogenic organisms from one person to another

Question 19

Name 6 ways to prevent cross infection in the dental surgery (6)

Answer 19

1. Decontamination of instruments
2. Zoning
3. Hand hygeine
4. Clinical waste disposal
5. PPE
6. Sharps Injury Management