BACKGROUND: Non-surgical and surgical periodontal treatment may cause volumetric changes in the gingival contour. Many techniques have been suggested to minimize soft tissue shrinkage; however, there is a lack of three-dimensional (3D) quantitative data comparing different treatment approaches. The aim of the present study was to clinically validate an easy-to-use chair-side procedure to document volumetric changes in the interdental papilla region. METHODS: Nine volunteers participated in the study. A thin layer of a flowable composite resin material was applied on a papilla and volumetrically analyzed using the clinical chair-side computer-aided design/computer-aided machining (CAD/CAM) 3D method. To accurately measure the applied volumes, the composite resin volume was also determined using microcomputed tomography (micro-CT) and weight measurements. In addition, inter- and intraexaminer differences were evaluated in the same manner using a dental training unit (phantom head) to simulate clinical conditions. RESULTS: No statistically significant difference was found between the results obtained by micro-CT and the weight measurements. The CAD/CAM 3D method showed a significant underestimation of the composite resin volume (P = 0.0047) compared to micro-CT, although the two methods correlated well (R(2) = 0.991). High accuracy was found when inter- and intraexaminer differences were evaluated, showing a concordance correlation coefficient of 0.99. CONCLUSION: CAD/CAM 3D device and software are an easy-to-use chair-side method to document changes in soft tissues.