Decontamination Sciences

Question 1

GDC requirement

Answer 1

1.5 Treat patients in a hygienic & safe environment
- Health & Safety
- Decontamination
- Medical Devices
Important for patient perceptions

Question 2

operator

Answer 2

defined as any person with the authority to operate a sterilizer/washer disinfector including the noting of device readings and simple housekeeping duties

Question 3

record keeping for decon

Answer 3

If it is not documented it did not happen

Audit been through decontamination and sterilisation practice and quality check

Question 4

shortcomings in dental practice decon before addressing

Answer 4

Several shortcomings
- Combined with eating area, storage for staff

Potential mix up of clean and dirty

Question 5

dental practices scotland now

Answer 5

among the best as of high standards and continued training

Packaged sterilised equipment – how they are stored

Question 6

standardised way equipment stored in dental hospitals and practices

Answer 6

Package sterilised instruments have standard in hospital and in practice
- equal level

Question 7

3 levels of spaudling classifications

Answer 7

critical - needs to e sterile

semi-critical - sterile preferable/high level disinfectant

non-critical - disinfectant/clean

Question 8

Critical spaudling classification

Answer 8

– devices that enter tissue that is usually sterile or enters the vascular system

• STERILE

Question 9

non-critical spaudling classification

Answer 9

– Instruments have contact with intact skin only

– Disinfectant/ clean

Question 10

semi-critical spaudling classfication

Answer 10

– Instruments have contact with intact mucous membranes but does not penetrate sterile tissue

– STERILE preferable/ high level disinfectant but these have no place in dental practices

Question 11

eg dental semi-critical instuments

Answer 11

mirror (sterile preferable)

Question 12

e.g. dental critical instruments

Answer 12

handpiece

water irrigator

Question 13

what does the rise of ‘surgical’ dentistry mean

Answer 13

increased demand for sterile instruments

• more invasive
  mucoperiosteum flaps etc

Question 14

4 reasons why we need sterile instruments

Answer 14

reduces probability of infection transmission

International standard for surgical instruments.

Legislative and professional standards.

Maintaining high quality of care for patients

Question 15

invasive surgery needs

Answer 15

Any invasive surgery need sterile instruments

• Wrapped before going into steriliser
• When receive from steriliser will remain sterile until unwrapped

all dental surgical instruments

Question 16

issue with type N non-vacuum sterilisers

Answer 16

evidence non-vacuum sterilizers (type N) fail to achieve sterilization conditions inside dental handpieces

Question 17

sterile means

Answer 17

For a terminally-sterilized medical device to be designated “STERILE”, the theoretical probability of there being a viable micro-organism present on/in the device shall be equal to or less than 1 x10^(-6)

Question 18

life cycle of re-useable surgical instruments

Answer 18

acquisition - purchase/loan

cleaning ->
disinfection ->
inspection ->
(disposal - scrap/return)

packaging -> 
sterilisation ->
transport -> 
storage -> 
use -> 
transport -> 
cleaning again

Question 19

operator level of decon sciences

Answer 19

Keep it simple
- Single use devices where practical
- Automated washer-disinfectors
- Inspection
- Pouch it (paper or clear bag)
& sterilize it (type B process)

Record Keeping

Additional resources SDCEP – decontamination in practice

Question 20

BBVs

Answer 20

HIV 
Hep B 
Hep C
vCJD
Herpes Simplex

Question 21

HIV transmission dental concern

Answer 21

Aware of HIV transmission in dentistry
- news report from the USA about patient Kimberly Bergalis experience

There are many publications about this “Acer” Florida dentist case & HIV transmission in dentistry.

little evidence of HIV and dental transmission link

Question 22

hep B and C infection transmission in dental practice

Answer 22

concerns (recent as 2009)

large press converage

Question 23

more common BBV dental transmission with

Answer 23

herpes simplex

Question 24

improvements in decon dental transparency

Answer 24

Improvements prompted most recently by
2007 DOH risk assessment for vCJD & dentistry
- Press influence public perception need to be transparent and active about dental decontamination procedures

Question 25

why worry about vCJD?

Answer 25

Prions more difficult to inactivate on surgical devices

Infectivity can survive steam sterilization at 134°C for 18 minutes

Question 26

dental relevance of prion research

Answer 26

This study provides evidence that in animal models;

Infectivity was found in both dental pulp and the gingival margin within 3 weeks of challenge with infectious prion

Exposure to deliberately contaminated dental files, 68 of 70 mice (97%) of mice developed clinical disease – worst case scenario

Question 27

cases of vCJD

Answer 27

Cases are low (n=178 UK) but asymptomatic carriage may be relatively high

Suspected asymptomatic vCJD carriage in UK = approx. 1 in 2,000 (but wide confidence intervals)

Question 28

risk of bacterial cross infection in dentistry

Answer 28

Post operative treatment or complication of dental surgery

• Need investigated and monitored
• better documentation needed for post op

Infection transmission in dental practice
- An implant periapical lesion leading to acute osteomyelitis with isolation of Staph aureus

Question 29

S.aureus and oral infections

Answer 29

This study provide evidence that S. aureus can cause dento-alveolar infections.
- N= 1,986 from 11,312 specimens (18%)

But what is the source & how did cross infection occur?
- endogenous or exogenous ?

Question 30

what bacteria can be recovered from inside dental hand-pieces (after use, before decon)

Answer 30

Oral streptococci,
Pseudomonas spp &
Staphylococcus aureus.

Need to get sterilisation in dental practice – type B or vacuum