Dental calculus and ultrasonic scalers

Question 1

what causes periodontal disease?

Answer 1

plaque bacteria initiating the bodies immune response

Question 2

what is dental plaque?

Answer 2

biofilm from bacteria found in the mouth, its soft so can be removed by a toothbrush, reduced by OH

Question 3

what is the purpose of periodontal treatment?

Answer 3

reduce pathogens in the sub-gingival biofilm to a level which is conducive to healing

Question 4

what is calculus?

Answer 4

plaque that has been calcified onto teeth

Question 5

is calculus seen sub or supragingivally?

Answer 5

both

Question 6

where is calculus commonly found?

Answer 6

lower incisors lingually due to submandibular/sublingual salivary gland
also seen upper 6 at parotid gland secretes here

Question 7

why should calculus be removed?

Answer 7

If left it provides a rough surface which attracts further plaque bacteria

Question 8

can calculus be removed by toothbrushing?

Answer 8

no, it’s tough so has to be removed professionally

Question 9

what colour is supragingival calculus?

Answer 9

yellow/brown

Question 10

where is supragingival calculus heaviest?

Answer 10

lingual lower incisors and buccal upper molars

Question 11

how do u detect supragingival calculus?

Answer 11

Dry the tooth, it appears matt (careful - it looks similar to demineralised enamel)

Question 12

what colour is subgingival calculus?

Answer 12

dark green/black

Question 13

where is subgingival calculus heaviest?

Answer 13

same throughout the mouth

Question 14

how do you detect subgingival calculus?

Answer 14

feel using BPE or cross calculus probe
radiograph (remember limitations)

Question 15

what is a limitation of using a power scaler?

Answer 15

harder to detect residual deposits so check with it turned off

Question 16

which one has a thinner tip, power or hand scaler?

Answer 16

power scaler

Question 17

power scalers work by causing cavitation bubbles, what are these?

Answer 17

The scaler moves so fast it generates cavitation bubbles which then collapse creating a second shockwave which generates pressure and heat that knocks the calculus off and kills anaerobic bacteria

Question 18

power scalers work by causing acoustic microstreaming, what is this?

Answer 18

movement of fluid adjacent to vibrating tip, generates stress within the immediate area damaging bacterial cell membrane, water flushes dead bacteria and their products out of the pocket

Question 19

name the types of ultrasonic scalers

Answer 19

piezo-electricity or magnetostriction

Question 20

an ultrasonic scaler tip oscillates at what frequency?

Answer 20

25042 kHz

Question 21

why do you have to be cautious with piezo-electricity ultrasonic scalers?

Answer 21

Also used to remove dentine and caries

Question 22

why do you have to be cautious with magnetostriction ultrasonic scaler

Answer 22

The stack oscillates/vibrates so if held too hard it can stop the tip oscillating/vibrating properly
Fast so generates heat so need water

Question 23

how does a sonic scaler work?

Answer 23

generated from passage of compressed air

Question 24

a sonic scaler tip oscillates at what frequency?

Answer 24

6-8kHz

Question 25

describe the tip movement of a sonic scaler

Answer 25

elliptical -> circular

Question 26

disadvantage of sonic scalers?

Answer 26

Causes more damage to root surface

Question 27

what do you have to be cautious of when using ultrasonic/sonic scalers?

Answer 27

indwelling cardiac devices
respiratory infections AGP
decalcified enamel
ceramics and implants can be scratched

Question 28

what are potential hazards of powered scalers?

Answer 28

thermal damage to tooth
incorrect angulation can damage tooth surface

Question 29

but these surfaces in order of energy distribution from most to least powerful

Answer 29

Question 30

what surfaces can you use directly on the tooth?

Answer 30

Use the concave surface and lateral sides, never the tip directly on the tooth