Purpose: To evaluate the sensitivity and specificity of the near-infrared light transillumination caries detection method by using DEXIS CariVu (DCV) for imaging of interproximal primary molar surfaces (IPMS).<br/>Methods: A retrospective evaluation of patient records at a university pediatric dentistry (PD) clinic identified 22 patients with unrestored IPMS, which had images of both bitewing radiography (BW) and DCV. A scoring system (no caries, incipient caries, dentinal caries) was developed for the study. Two investigators (pediatric dental faculty) identically scored 90 IPMS in both BW and DCV images, establishing benchmark IPMS scores. The 180 images were then compiled in a randomized order in a questionnaire, which was answered by 24 raters (PD residents and faculty) using the study caries scoring system. Data analysis included raters and experts' percent agreement, Vassar Stats for sensitivity and specificity, and Kendall's correlation coefficient for interrater reliability.<br/>Results: The overall agreement between raters and experts for DCV images was 48 percent (54 percent for no caries, 23 percent for incipient caries, and 68 percent for dentinal caries). The DCV's sensitivity and specificity to detect any caries were, respectively, 0.72 and 0.54, 0.60 and 0.53 for incipient caries, and 0.82 and 0.53 for dentinal caries. The BW's sensitivity and specificity to detect any caries were respectively, 0.82 and 0.87, 0.98 and 0.86 for incipient caries, and 0.99 and 0.87 for dentinal caries. The overall interrater reliability was 0.48 (95 percent confidence interval equals 0.46 to 0.50).<br/>Conclusion: The use of DCV as a stand-alone caries detection method for IPMS is limited.