Evaluating early approximal caries lesions through radiographs in clinical research can be approached in various ways. Traditionally, clinicians rely on bitewing radiographs to visually assess changes in the depth of the lesions. With the shift in modern dental practices towards prevention rather than intervention, researchers are on the lookout for reliable methods that can detect early changes in lesion size.

This paper explores three different radiographic interpretation techniques: 1. digital subtraction radiography (DSR), 2. histogram analysis (HA), 3. The combination of DSR and HA. Research indicates that DSR is a valuable tool in supplementing visual interpretation, particularly in high caries risk cases due to its heightened sensitivity. However, there's been confusion surrounding the correct interpretation of DSR radiographs. This paper aims to shed light on the proper techniques for performing and interpreting DSR and introduces a novel method that combines DSR with HA.