THE MACH BAND OPTICAL EFFECT AND ITS INFLUENCE ON THE IDENTIFICATION OF INTERPROXIMAL CARIES

Abstract

Dental caries is a chronic disease affecting the teeth; proximal surfaces are particularly susceptible due to food retention and cleaning difficulties. Radiographic interpretation can be compromised by errors related to professional perception, and optical effects can influence the accurate analysis of radiographs. This study aimed to evaluate the ability to identify early-stage proximal caries in periapical and interproximal radiographs—both digitized conventional and digital—and to assess the interference of the Mach band effect on image interpretation. A questionnaire featuring images of caries or the Mach band effect was completed by 84 dental students and 79 qualified dental professionals. Across all groups, the correct identifications proposed in the questions showed the highest frequencies of accuracy. Incorrect identifications were more common regarding interproximal radiographs, whereas the "Not identified" option was more prevalent for periapical radiographs. It is concluded that deepening knowledge regarding optical effects—especially the Mach band—is essential due to their relevance in interpreting both conventional and digital radiographs. This aims to ensure greater reliability in implementing early and effective treatment for patients.