Miscellanea 
237 
III. The Tooth-Brush and Decayed Teeth. 
By FRANK ROCK, M.D. 
The use of the tooth-brush is generally regarded not merely as an essential of cleanliness 
but also as necessary in order to prevent decay of the teeth. The question as to whether there 
is any correlation between the use of the tooth-brush and the amount of decay is therefore 
an interesting one. 
Below are two tables giving the condition of the teeth found at the medical inspection 
of two boys' and three girls' schools at Edmonton during the last two years. All the children 
are over thirteen years of age. The children in row A clean their teeth at least once a day ; 
those in row B use a tooth-brush occasionally ; this may mean once a week or once a fortnight 
or in fact any period that will allow a child's conscience to answer that it uses a tooth-brush 
occasionally ; those in row C never use a tooth-brush. 
TABLE I. Boys. 
Number of Decayed Teeth. 
0 
1 
2 
3 
4 
5 
6 
7 
8 
Totals 
A 
48 
32 
24 
10 
3 
1 
1 
119 
B 
59 
58 
38 
21 
8 
4 
1 
189 
0 
89 
67 
47 
30 
14 
1 
248 
Totals 
196 
157 
109 
61 
25 
6 
1 
1 
556 
Mean number of decayed teeth : A, M344 ; B, 1*3492 ; C, 1-2508; all the boys, 1-2626. 
TABLE II. Girls. 
Number of Decayed Teeth. 
0 
1 
2 
3 
4 
5 
6 
Totals 
A 
86 
44 
56 
27 
13 
2 
1 
229 
B 
66 
51 
36 
23 
5 
2 
183 
C 
38 
29 
13 
10 
3 
2 
95 
Totals 
190 
124 
105 
60 
21 
6 
1 
507 
Mean number of decayed teeth : A, 1-3319 ; B, 1-2131 ; C, 1-1263 ; all the girls, 1-2505. 
The best way of grouping to form a two-row table would be to combine B and C together 
since the occasional use means practically very little use of the tooth-brush. This was done 
