PER02-2004 Flashcards
What is periodontology?
Study of the periodontium in health and disease
What are the four main tissues that form the periodontium?
Cementum
Periodontal ligament
Alveolar bone
Gingiva
What is the number 1 cause of tooth loss?
Periodontitis
What do healthy gingivae look like?
Pale pink and even colour
Scalloped appearance (gumline)
Flat, sharp, knife-edge, triangular interdental papillae
(Stippling of attached gingiva in ~30% of people)
What are the clinical signs of gingivitis?
Erythema/redness
Oedema/swelling
Bleeding on probing or brushing
Which of gingivitis and periodontitis is irreversible?
Periodontitis
What are the clinical signs of periodontitis?
Those seen in gingivitis as well as:
Pocket formation
Tooth mobility
Gingival recession
Tooth drifting
Halitosis
Tooth loss
Define periodontal disease.
Bacterially-induced, immune-mediated inflammatory disease of the tissues supporting the teeth
What is the primary aetiological factor in periodontal disease?
Plaque
What are the necessary prerequisites for periodontal disease initiation and progression?
Virulent periodontal pathogens
Local environment (favouring these pathogens)
Host susceptibility
How many micro-organisms can be found in the oral cavity?
> 700 species (multi-kingdom)
On what surfaces does dental plaque form?
Hard, non-shedding surfaces in the mouth
What factors might affect the growth of microbes in the mouth?
Temperature
Redox potential/oxygen tension
pH
Nutrient availability
Host defence
Name some resident bacteria in the mouth.
Streptococcus (most prevalent)
Actinomyces
Eubacteria
Lactobacillus
Neisseria
Veillonella
Haemophilus
(and many more)
What is the most common fungal genus in the mouth?
Candida
What is the difference between planktonic and sessile growth?
Planktonic = floating in saliva
Sessile = attached to a surface
Define dental plaque.
Biofilm
Complex microbial community that develops on the hard, non-shedding surfaces in the mouth, embedded in a matrix of polymers of bacterial and salivary origin
What is the difference in nutrients for supragingival and subgingival plaque?
Supra = nutrients from diet/saliva, carbohydrates mainly
Sub = nutrients from gingival crevicular fluid, proteins mainly
What are plaque-retentive factors?
Secondary local factors
Increase surface area for plaque and are usually hard to clean so increase risk of periodontal diseases
Give an example of a plaque-retentive factor.
Calculus
Restoration defects or overhangs
Lack of saliva/xerostomia
Tooth position, shape/abnormalities
Gingival anatomy
Removable prostheses
What kind of patients may have xerostomia?
Mouth breathers, incompetent lips
Those taking polypharmacy
Those with certain conditions, eg Sjogren’s syndrome
What are the key systemic factors affecting periodontal disease?
Smoking
Diabetes
Pregnancy
Medication
Genetics
How does smoking affect periodontal disease?
More likely to:
- develop periodontitis
- develop periodontal pockets
- experience greater bone loss
- lose teeth
Masks gingivitis/bleeding and impairs healing
Decreases efficacy of/response to treatment
How does uncontrolled diabetes affect periodontal disease?
Poor glycaemic control increases the risk of periodontal disease and its progression
Impairs the immune response and wound healing
Increases risk of recurrent/multiple periodontal abscesses
How does pregnancy affect periodontal disease?
Increases gingival response to plaque and increases gingival blood flow
Which drug groups may cause drug-induced gingival overgrowth?
Calcium channel blockers (hypertension, eg nifedipine/amlodipine/felodipine)
Phenyltoin (epilepsy)
Ciclosporin (immunosuppressant)
Why might a patient be taking calcium channel blockers?
Hypertension
Why might a patient be taking phenyltoin?
Epileptic
The lack of which immune cell is most detrimental in periodontal disease?
Neutrophils/PMNs
Give examples of some hereditary neutropenic conditions.
Papillon Lefevre syndrome
Chediak-Higashi syndrome
Leukocyte adhesion syndrome
What is epidemiology?
Study of distribution of disease/physiological condition in human populations and the factors that influence it
What is descriptive epidemiology?
Description of the distribution of a disease in different populations
What is aetiological epidemiology?
Considers the aetiology of a disease from the combination of the descriptive epidemiological data along with other information (eg genetics, microbiology, sociology)
What is analytical epidemiology?
Evaluation of the consistency of epidemiological data with hypotheses developed clinically or experimentally
What is the point of experimental epidemiology?
Provides a basis for developing and evaluating preventative programmes and public health practices
What is the importance of epidemiology in periodontal disease?
Helps us to determine:
- the impact of the disease
- any aetiological factors
- treatment needs and effects
What are the issues with periodontal disease epidemiology?
Periodontal disease has a gradual onset and varies widely in severity
Periodontal disease is “site-specific”
Have to take partial recordings instead of full assessments for practicality (so may miss disease)
No universally agreed standards for defining its stages
No set parameters to measure
Hard to collect data in community settings (outside of dental practice)
What does “incidence” mean?
Number of new cases per year (in a population)
What does “prevalence” mean?
Total number of cases (in a population)
Why is probing depth insufficient for measuring periodontal disease?
Must measure attachment loss so must consider recession (esp in elderly)
Also need to measure extent/number of teeth affected
Why does the Adult Dental Health Survey most likely underestimate the amount of periodontal disease in a population?
Only uses partial mouth recordings
Not always conducted in the dental practice
Describe the epidemiology of gingivitis.
Highly prevalent in adults >60%
Associated with levels of plaque
Describe the epidemiology of periodontitis.
Mild-moderate periodontitis = 20-35% of pop.
Severe periodontitis = 10-15% of pop.
What did the Natural History of Periodontal Disease in Man - Loe et al., 1986 study show?
(Parallel cohort longitudinal study)
In populations both educated and uneducated in oral hygiene practices, a similar pattern of periodontal disease is present
Most people will have moderate susceptibility to periodontal disease, but a small proportion will be either low or high susceptibility (bell-curve)
Some people have a resistance to periodontal disease even in the presence of poor plaque control
What are the features of a low risk periodontal disease patient?
Little/no bone loss
Periodontal inflammation with no pocketing
Keep teeth until old age
What are the features of a normal risk periodontal disease patient?
Slowly progressing periodontal disease
Associated with poor plaque control
Risk of some tooth loss with advancing age
Horizontal bone loss
What are the features of a high risk periodontal disease patient?
Severe periodontal disease at an early age
Severe periodontal disease even with good plaque control
Risk of tooth loss by age 40
Irregular bone loss
Describe the WHO probe.
0.5mm ball end
Black band from 3.5-5.5mm and 8.5-11.5mm
What is the BPE?
Screening tool to give a provisional periodontal diagnosis
gives an insight into treatment needs
What are the sextants in a BPE?
7-4, 3-3, 4-7 on both arches
What leads to a code 0 BPE?
Health
No bleeding on probing, no calculus/overhangs
Black band is fully visible
What leads to a code 1 BPE?
Bleeding on probing
Black band is fully visible
No calculus/overhangs
What leads to a code 2 BPE?
Bleeding on probing
Black band is fully visible
Presence of calculus/overhangs
What clinical sign shows localised gingivitis?
Bleeding on probing 10-30%
What clinical sign shows generalises gingivitis?
Bleeding on probing >30%
What is a reduced periodontium?
Stable/successfully treatment periodontitis (gums have receded due to attachment loss)
What is the key feature of an intact periodontium?
No probing attachment loss
What are the parts of a gingivitis diagnosis?
Extent of bleeding on probing (inflammation level)
Intact or reduced periodontium (attachment loss)
Which BPE codes need radiographs? What feature is essential in these images?
Codes 3 and 4
Crestal bone levels
What leads to a code 3 BPE?
Bleeding on probing
May or may not have calculus/overhangs
Black band partially covered
What leads to a code 4 BPE?
Bleeding on probing
May or may not have calculus/overhangs
Black band fully covered
What are the possible disease extent patterns for periodontitis?
Localised = <30% of teeth
Generalised = >30% of teeth
Molar-incisor pattern
How is the staging of periodontitis calculated?
Periapical radiograph
Bone loss as a percentage of root length of the worst affected tooth
What is staging of periodontitis?
Severity, how much bone loss has occurred
What are the levels of staging in periodontitis?
Stage 1 (early/mild) = <15%
Stage 2 (moderate) = 15-33% (coronal third)
Stage 3 (severe) = 33-66% (middle third)
Stage 4 (very severe) = >66% (apical third)
What is grading of periodontitis?
Rate of progress, susceptibility
How is grading of periodontitis calculated?
Percentage bone loss of worst affected tooth ÷ age
What are the levels of grading in periodontitis?
Grade A (slow) = <0.5
Grade B (moderate) = 0.5-1
Grade C (rapid) = >1
What probing pocket depth suggests currently unstable periodontitis?
5mm
What is the difference between currently stable and currently in remission diagnoses?
Currently stable has <10% BoP
Currently in remission has >10% BoP
(both have pocket depths ≤4mm)
