29. Dental Plaque Flashcards
Key features of dental plaque
- a biofilm of microbial species
- forms an extracellular polysaccharide matrix
- many species in complex, diverse community - a stable ecology
- dynamic community - adapts to external stimuli
- different constituent flora at aerobic and anaerobic sites
What is the DMFT index?
- Decayed, Missing and Filled Teeth Index
- summary of cumulative caries experience
- measures number of teeth that are decayed, missing (due to caries) or filled
- used in epidemiological studies
How to measure DMFT?
- score a tooth as 1 if decayed, missing due to caries or filled
- score 0 if otherwise
- all measurements are 1 or 0 - dichotomous measure
- 3rd molars included, score of 32
- do not include teeth missing due to reasons other than caries (unerupted, missing, extracted for othodontic/periodontal reasons)
Highest possible DMFT
32
Give a variety of the DMFT
DMF (surface) index
- quantify extent of disease
Limitations of the DMFT
- gives equal weight to missing, untreated caries or well restored teeth
- no measurement of extent of caries
- doesn’t consider other disease processes like periodontal disease
- no indication of teeth at risk
- sealants or PRRs given same weighting as heavily restored teeth
- rate of caries progression can not be assessed
- doesn’t represent current treatment needed
Why do we measure dental plaque?
- indicate extent of plaque coverage of teeth
- used in epidemiological studies but also useful resource for individual patient care
Give plaque indices
- Plaque coverage index
- Silness and Loe Plaque Index
- Oral Hygeine Index (Green and Vermillion)
- Simplified Oral Hygeine Index
- Modified Plaque Index by Schick and Ash
- (Modified) Quigely Hein Index
- Navy Plaque Index
Explain Plaque Coverage Index
- measures number of surfaces with plaque present
- divide tooth into 6 areas (mesio-buccal, mid-buccal, disto-buccal, mesio-palatal, mid-palatal, disto-palatal (or ML,L,DL))
- assess whether or not plaque is present on each surface
- calculate percentage of surfaces present with visible plaque
DO NOT do what 2 things in plaque coverage index?
- do not score occlusal surfaces
- do not quantify amount of plaque - either present or absent
Explain finger rest
- whenever applying dental instruments to teeth (such as a probe), use finger rest
- stabilises and provides control to working hard
Clinical technique of plaque coverage index
- cross infection
- patient positioning/lighting
- mirror and periodontal probe
- tell nurse which teeth are missing - crossed out on chart
- systematically relay yes/no to nurse
- upper buccal, upper palatal, lower buccal, lower lingual
- use midline as checkpoint
On a chart, you … missing teeth and … surfaces with … for a plaque coverage index
- cross out
- blank out
- plaque present
How to work out plaque coverage index
- total number of surfaces = number of teeth x 6
- number of surfaces where plaque is present = number of shaded areas in chart
- plaque index = number of surfaces with plaque / total number of surfaces (all x 100)
What are disclosing tablets?
- harmless vegetable dye which stains plaque deposits in patient’s mouth
- thoroughly chewed tablet then rinse with water before examining areas
2 types of disclosing agents
- other type stains all plaque pink
- new type stains newer plaque pink and older plaque blue
Ads and disads of disclosing tablets
- very useful
- but watch for staining
How to avoid longer staining with disclosing tablets?
- apply Vaseline to lips first
- offer patient a prophylaxis/polish after
What is the Silness and Loe Plaque Index?
- from 1964
- used when we want to measure amount of plaque present on each surface
- like the Plaque Coverage Index, ignore occlusal surfaces
- has it’s own scoring criteria
Scoring Criteria for Silness and Loe Plaque Index
0 - no plaque
1 - film of plaque, visible only by removal on a probe
2 - moderate accumulation of deposits visible with naked eye
3 - heavy accumulation of plaque
How are teeth divided in Silness and Loe?
- each tooth into 4-6
- in Newcastle, we use 6
- mesio-buccal, mid-buccal, disto-buccal, mesio-palatal, med-palatal, disto-palatal (or ML,L,DL)
- usually excludes 8s
How to chart Silness and Loe plaque index?
- tell assistant which teeth are missing before starting
- read out score for each surface working systematically dentition like with Plaque Coverage Index
Calculation for Silness and Loe
- total number of surfaces = number of teeth x 6
- total S and L plaque score is all numbers added together
- plaque index = total S and L plaque score/total number of surfaces
Clinical technique for any plaque index
- patient positioning
- good lighting
- air dry tooth with 3 in 1 tip
- mirror and probe
- posture
How to control cross infection
- personal protective equipment (mask, gloves, safety glasses)
- hair tied back, bare below elbow
- patient protection (safety glasses, bib)
- effective hand hygeine
- clean and dirty zones
- disposal of equipment
