KPG Index versus OPG Measurements: A Comparison between 3D and 2D Methods in Predicting Treatment Duration and Difficulty Level for Patients with Impacted Maxillary Canines

Table 1

Contingency table comparing KPG index vs. Stewart’s measurement.

(a)

KPG	Stewart		Total
	Shorter	Longer
Shorter	66	12	78
Longer	12	15	27
Total	78	27	105

(b) Chi-square tests

	Value	𝑃 value
Pearson correlation (𝑟)	0.402	0.017*
Yates χ ^2	3.741	0.053
Positive likelihood ratio	1.904
Negative likelihood ratio	0.277
Sensitivity	0.846
Specificity	0.556
Positive predictive value	0.846
Negative predictive value	0.556

 *Statistically significant association.