Aetiology of periodontal disease: Local Factors

Question 1

What crystals make up dental calculus?

Answer 1

calcium and phosphate crystals

Question 2

How would you describe supragingival calculus?

Answer 2

Found in sites of saliva pooling, light coloured and frosted

Question 3

Give 7 examples of other local plaque retentive features

Answer 3

• Tooth position
• Gingival anatomy
• Tooth shape/abnormalities
• Root anatomy
• Carious cavities
• Overhanging restorations
• Removable prostheses/appliances

Question 4

What are the problems with anatomical plaque retentive factors?

Answer 4

Tooth position/malalignment or crowding makes it more difficult to clean between and remove plaque.

Also bigger IP gaps can promote food packing, so patients need to remove this debris to help prevent plaque build up

Question 5

How does gingival anatomy affect plaque retention?

Answer 5

Gingival overgrowth traps plaque.

Or for example, an overgrown frenum could make the area harder to clean

Question 6

Give 3 examples of root anatomy/abnormalities which may affect plaque retention

Answer 6

Furcations of molars/premolars (additional surface for plaque to attach to, harder to clean)

Root depression e.g. canine fossa first premolar

Root grooves

Question 7

Who might be more prone to xerostomia?

Answer 7

Mouth breathers: incompetent lips, drying of labial tissues

Polypharmacy

Certain medical conditions e.g. Sjogren’s or rheumatoid arthritis

Salivary gland issue

Question 8

Which disease do local factors particularly affect?

Answer 8

Gingivitis