Investigation of the effectiveness of fluorescent light in the evaluation of access cavities prepared by dental students in retreatment cases: An in vitro study

This study aimed to evaluate the effects of different visual aid methods (no magnification [control group], operating microscope, and REVEAL fluorescence-assisted magnification device) on the success of restorative material removal and procedure time during nonsurgical endodontic retreatment. The study was conducted with 4th-year, 5th-year, and postgraduate endodontic students at the Department of Endodontics, Faculty of Dentistry, Selçuk University. Each participant was provided with three tooth samples to be examined without magnification, with an operating microscope, and with the REVEAL device. After removal of the restorations, all samples were scanned using the TRIOS 5 intraoral scanner. The obtained Standard Triangle Language (STL) data were superimposed with the initial scans in Geomagic Control X software to perform a 3D comparison, and RMS (root mean square) values were calculated. RMS values were interpreted as indicators of the amount of tooth tissue removed and the amount of composite material remaining. According to the findings, the REVEAL device showed the lowest RMS values across all participant groups and was recorded as the fastest method in terms of procedure time (p<0.05). The control group ranked second in terms of procedure time, while the operating microscope group required the longest duration. No significant difference was found between the operating microscope and the control group regarding RMS values (p>0.05). When comparing educational levels, a significant difference in procedure time was found only between the 4th-year group and the postgraduate group (p<0.05). The results revealed that the REVEAL device facilitates the differentiation of tooth and composite material, supports a minimally invasive approach, reduces procedure time, and does not require additional training for users with different experience levels. Despite offering high magnification, the operating microscope provides more limited benefits in educational settings at the initial stages, as it requires adaptation and prolongs procedure time. The control group, while faster than the operating microscope, was not as successful as REVEAL in terms of minimally invasive outcomes. These findings demonstrate that the use of fluorescence-assisted devices in dental education and clinical practice has the potential to enhance treatment success. Keywords: Fluorescence, nonsurgical endodontic retreatment, operating microscope, REVEAL device, RMS, 3D compare