Table 1.

Criteria of evaluation for dental caries and tooth crack.

	Score	ADA * Criteria	QLF Criteria	ADA * Criteria	X-ray Criteria
Occlusal dental caries	0	Sound	No fluorescence loss and no red fluorescence increase in pits and/or fissures	Sound	No radiolucency visible
	1	Initial	Fluorescence loss and red fluorescence present as a line or spot in pits and/or fissures	Initial	Radiolucency visible in the enamel
	2	Moderate	Fluorescence loss and red fluorescence glow extending around pits and fissures	Moderate	Radiolucency in the dentine but restricted to the outer 1/3 of the dentine
	3	Advanced	Red fluorescence glow extending around pits and fissures and a dark shadow from dentin present	Advanced	Radiolucency extending to the middle 1/3 of the dentine
Proximal dental caries	0	Sound or Initial	No fluorescence loss and no red fluorescence increase in occlusal surface (mesial or distal side)	Sound
	1	Moderate	Fluorescence loss and red fluorescence present in occlusal surface (mesial or distal side)	Initial	Radiolucency visible in the enamel
	2	Advanced	Fluorescence loss and red fluorescence glow extending around occlusal surface (mesial or distal side)		Radiolucency in the dentine but restricted to the outer 1/3 of the dentine
	3			Moderate	Radiolucency extending to the middle 1/3 of the dentine
	4			Advanced	Radiolucency in the pulpal 1/3 of the dentine
	Score		QLF Criteria		Visual Criteria
Crack	0		No fluorescence loss and no red fluorescence increase in crack site		No detectable crack line
	1		Fluorescence loss and red fluorescence present as a line in crack site		Ambiguous detectable crack line
	2		Fluorescence loss and red fluorescence glow extending around crack site		Distinct detectable crack line

* Source: ADA (American Dental Association) Caries Classification System [26].