The purpose of this study was to evaluate the ability of Q-ray view (All-in-one Bio, Seoul, Korea) in detection
of proximal caries in primary molars with sound marginal ridges.
Thirty two children aged 3-9 years (average 5.6 ± 1.3 years old) were chosen, and two examiners evaluated
100 proximal surfaces of primary molars with sound marginal ridges. The teeth were examined with; (a) visual
examination, (b) Q-ray view, (c) DIAGNOdent (KaVo, Biberach, Germany) and (d) digital periapical radiography.
Kappa statistic was used to assess the agreement between each examination method and the degree of caries
progression. The kappa values for enamel caries were 0.15 (visual examination), 0.10 (Q-ray view), 0.25
(DIAGNOdent) and 0.68 (digital periapical radiography). The kappa values for dentinal caries were 0.34 (visual
examination), 0.56 (Q-ray view), 0.44 (DIAGNOdent) and 0.70 (digital periapical radiography).
Although Q-ray view showed low diagnostic ability in detection of enamel caries, it was effective in detection of
hidden proximal caries extended into dentin. Q-ray view would be a useful and simple device which could aid
pediatric dentists in detection of hidden proximal caries in primary molars especially when examining uncooperative
children or disabled persons.