Periodontal Indices Flashcards
How can you identify disease?
Data Collection
- personal interview
- questions of a surrogate
- written questionnaire
- scrutinizing pre-existing records
- direct examination
Symptoms, Signs and Tests
- subjective observations by the patient
- perceptions and observations by the examiner
- quantifiable measures of physiologic, immunologic, and biochemical processes
what two factors can affect the accuracy of an examination?
Reproducibility (examiner; instrument; condition)
- the ability to produce the same result (e.g., gingivitis) every time the test was repeated in the same patient
Validity (predictive; content; criterion-related)
- the ability of a test to discriminate between people with and without disease
How can the true value of a diagnostic test be assessed?
the true value of a diagnostic test is a combo of both the reliability and the validity of the data. For example, if a test is designed to discriminate between health and disease, then a highly reliable and valid test will have values centered around the true value every time the test is used. A highly reliable, but poorly valid test will produce the same result every time the test is used. A highly variable, but poorly valid test will produce the same result every time, but the result is not correct. A poorly reliable, but highly valid test will not detect the result every single time, but will be correct some of the time.
What’s sensitivity?
- the probability that a test result will be positive when the test is administered to people who actually have the disease in question
- sensitivity = Pr(T+/D+)
What’s specificity?
the probability that a test will be negative when administered to people who are free of the disease in question.
specificity= Pr(T-/D-)
What’s Predictive Value Positive (PVP)?
- the probability of disease in a subject with a positive test result
- PVP = Pr (D+/T+)
what’s Predictive Value Negative (PVN)?
- the probability of not having the disease when the test is negative
- PVN = Pr (D-/T-)
What are some potential problems (examiner bias) when diagnosing?
Halo Effect
Leniency/Severity Error
Central Tendency Error
What’s the halo effect?
the examiner’s general impression of target distorts his/her perception of the target on specific dimensions
what’s leniency/severity error?
the examiner’s tendency to be lenient or severe
what’s central tendency error?
the examiner’s reluctance to rate at either the positive or negative extreme, so all scores cluster in the middle
what are some parameters commonly used in clinical periodontology?
- plaque accumulation
- calculus formation
- gingival inflammation
- periodontal destruction
- periodontal treatment needs
what’s the plaque index?
- the PI-I assesses the amount of plaque at the gingival margin, examine the same anatomical units as the GI
- plaque scores range from 0 to 3
- a probe is used to distinguish between scores 0 and 1. Visible plaque is scored a 2 or a 3
- the PI-I is computed for a tooth, subject, or population
- it parallels the GI of Loe & Silness
- first published by Silness & Loe
What’s the Silness and Loe plaque index (PLI)?
- introduced in 1967
- association of plaque and pregnancy gingivitis
- measures abundance of plaque
- no disclosing
- index teeth
What’s index teeth (Ramfjord teeth)?
- used by Ramfjord in 1957 to study disease progression
- tooth numbers - 3, 9, 12, 19, 25, 28
- advantages:
- representative of changes in entire mouth
- less time
What’s the scoring criteria for the plaque index?
0 - no plaque
1 - plaque detected by running probe margins
2 - visible plaque
3 - abundant plaque
What’s the Turesky Modification of Quigley-Hein Plaque Index scores?
Score 0 - no plaque
Score 1 - spots of plaque at cervical margin
Score 2 - thin, continuous band of plaque, 1 mm but, <1/3 of crown height
Score 4 - Plaque covering >_ 1/3 but <2/3 of crown height
Score 5 - plaque covering >_ 2/3 of crown height
What’s the Turesky Modification of Quigley-Hein Plaque Index?
- the quigley-hein index is biased toward the gingival third of the tooth surface
- facial and lingual surfaces are examined
- plaque is made visible using a disclosing agent and scored using a 0 to 5 scoring system
- scores are computed for subject, population
- it is the most frequently used plaque index in clinical trials
- quigley and hein (1962); turesky et al. (1970)
What are the NIDR Calculus index score?
0: calculus is absent
1: supra gingival calculus , but no sub gingival calculus is present
2: supra gingival and sub gingival, or sub gingival calculus only is present
What’s the Volpe-Manhold Index?
- determines the quantity of supra gingival calculus
- lingual surfaces os lower anteriors (#22-27)
- quantity is determined in mm of calculus along the 2 diagonal and the central lines drawn over the lingual surface of each tooth
- index, expressed in mm, is computed for tooth, subject, population
- most frequently used calculus index in longitudinal studies
- published by Volpe and Manhold (1962)
What are some calculus Indices?
Simplified Oral Hygiene Index (OHI-S) Periodontal Disease Index (PDI) Probe Method (Volpe-Manhold) Calculus Surface (Severity) index (CSI) Marginal Line Calculus Index (MLCI) NIDR Calculus Index
What’s the papillary-marginal- attachment (PMA) - Index
- background: the number of units affected correlates with the severity of gingival inflammation
- facial gingiva surface is divided in 3 scoring units P-M-A
- gingival units affected with gingivitis are counted. Presence or absence of inflammation is counted as 1 and 0, respectively
- severity component can be considered
- score computed for tooth, subject. and population
- first published by Schour & Massler (1947)
What parameters of gingival condition does Loe and Silness gingival index look at?
color
consistency
contour
BOP
What’s the gingival index?
- the severity of inflammation is assessed in 4 distinct gingival areas: distofacial papilla, facial margin, mesiofacial papilla, lingual gingival margin
- scores: 0 to 3; bleeding is considered. Presence of bleeding automatically leads to a score >_2
- score for tooth, subject, population
- useful for calculation of prevalence and severity in population and individual
- frequently used index in clinical trials
- first published by Loe and Loe & Silness
