Introduction: Systematically review the English literature for the best available evidence of the relation between the depth proximal caries identified on bitewing radiographs and the probability of lesion cavitation requiring restorative intervention. Methods: A search of the English scientific literature using MEDLINE, EMBASE, SCOPUS, Web of Science, and the Cochrane Library databases and using MESH terms such as dental caries, bitewing, and radiography was performed. Only in vivo study designs on human permanent posterior teeth using bitewing radiographs and direct visual inspection published in the last ten years were included. The articles were reviewed against a checklist for assessing a diagnostic or predictive test. Results: Only two articles met the inclusion criteria and were included in this systematic review. There was marked variation in the sensitivity and specificity of bitewing radiographs between the two studies. Conclusion: There is still controversy regarding the relation between caries lesion cavitation and lesion depth as determined by bitewing radiographs. However, the prevalence of caries in the population seems to be an important factor to consider..