Teeth excluded from the analysis because of a high frequency of abnormalities in the general population:
(1) maxillary lateral incisors
(2) third molars
(3) second premolars (agenesis)
Since there is a maximum of 32 teeth, the maximal number of teeth that can be assessed is 22 (4 third molars + 4 second premolars + 2 maxillary lateral incisors = 10)
|
Dental Component
|
Description
|
Classification Type
|
Severity Rating
|
|
root
|
normal
|
I
|
0
|
|
|
arrest with short, tapered V-shaped roots (more than 50% of normal root length)
|
II
|
1
|
|
|
anomalies in root number
|
IV
|
1
|
|
|
arrest with shortened, blunted roots (less than 50% of normal root development)
|
III
|
3
|
|
|
total arrest of root development
|
V
|
5
|
|
crown
|
normal
|
VI
|
0
|
|
|
enamel hypoplasia (notches on proximal surfaces)
|
VII
|
2
|
|
whole
|
microdontia
|
VIII
|
4
|
|
|
agenesis
|
IX
|
6
|
Based on the data shown in Table 2 (page 2647):
(1) more than one abnormality may be present, except with agenesis
(2) type II and III should not be present in the same tooth
(3) a type I tooth should not have a root abnormality
(4) a type VI tooth should not also be classified as type VII
mean disturbance severity rating =
= (CUMULATIVE SUM((number of teeth showing dental change) * (points for the severity rating))) / (number of teeth evaluated)
The most severe mean disturbance severity ratings were seen in children < 5 years of age who received >= 2,400 cGy of cranial radiation.
There are 2 ways to implement this rating system:
(1) A columnar input with a row for each potential tooth, with exclusions coded in.
(2) A simple listing of each classification item with the number of teeth showing those findings.
The second method is implemented because it is simpler, while the first would be more accurate.
