PEIO STUDIES

Question 1

Describe the Loe, Theilide and Jensen (1965) Theory in gingivitis - experimental gingivitis in man

Answer 1

• 12 dental students were taken (avg age 23)
• Had professional s/ps and were told to stop OH for 21 days
• Plaque and gingival indices were measured
• composition of plaque examined
• TBing and OH recommenced
• indices and plaque quality still monitored
• microbiological shifts could be seen

Question 2

What conclusions can we get from Loe, Theilade and Jenson theory

Answer 2

• Ceasing OH can lead to plaque accumulation and gingivitis which appeared after 10-21 days on surface
  -plaque composition changed - more filaments, more anaerobes/spirochetes
• condition is reversible if OH is restarted, plaque lost and gingivae returned to health.

Question 3

Describe the study on chlorohexadine (loe and schiott 1970)

Answer 3

-OH restarted with chlorohexidine rinse
- results showed that chlorohexidine removed plaque and returned to gingiva health
- significance was that the link between plaque and gingivitis confirmed and it excluded the idea of mechanical stimulation of the gingivae was involved.

Question 4

Describe the AGE study involved with gingivitis/perio disease

Answer 4

CHILDREN - accumulate large amounts of plaque but show little gingival inflammation
ELDERLY - severe inflammation associated with small amounts of plaque

THIS SUGGESTS THAT SUCCEPTIBILITY INCREASES WITH AGE

Question 5

Desribe the toothbrushing frequency study carried out by Lang, Cumming and Loe (1973)

Answer 5

method - dental students were instructed to brush at 12hr , 48, 72, and 96 hr intervals.
conclusions showed that - OH every 48 hrs sufficient in YOUNG, HEALTHY ADULTS with meticulous OH
- most pts do not attain such levels of OH and (probably) require mechanical oral hygiene at least two/three times a day.

Question 6

What is the specific plaque hypothesis (relates to sokransky study)

Answer 6

• a SINGLE pathogen (exogenous/endogenous)
• plaque without a specific microorganism
• no evidence that removing one species prevents disease

Question 7

Describe the non-specific plaque hypothesis

Answer 7

• no single organism responsible
• bacterial proliferation overcomes host resistance
• control/elimination - total plaque control and s/p

Question 8

What is Marsh’s ecological plaque hypothesis

Answer 8

1991and 94
- all bacterial conditions lead to build up of virulent bacteria/virulence factors
- there is a microbial balance and haemostasis but perio disease will be caused from an ‘upset’ in this balance (DYSBIOSIS)!

Question 9

When and where was Sokransky study carried out?

Answer 9

1998, at forsyth dental care in Boston
185 subjects , different levels of periodontal disease
over 13, 000 subgingival plaque samples were obtained
DNA hybridisation was carried out
results showed he found 5 clusters which he categorised by colour to identify which bacteria are associated with the onset and progression of perio disease

Question 10

Describe the study over electric vs manual tbing

Answer 10

• manual tb and ossolating tb were compared in there effectiveness
• cochrane review showed that using a powered tb compared to a manual tb there was an 11% reduction in plaque at 1-3 months of use and a 21% reduction in plaque when assessed after 3 months of use
• in terms of gingivitis, there was a 6% reduction at 1-3 months and an 11% reduction when assessed after 3 months of use