Table 2. Positive and Negative Results of Crack Diagnosis with CBCT and PR of Three Observers (Unit: number).

CBCT	PR
	Graduate		Endodontist		Radiologist
	+	-	+	-	+	-
+	4	30	5	31	5	34
-	0	10	0	8	0	5
S	30.00		31.00		34.00
P	< 0.001		< 0.001		< 0.001

S: standard variance.