En-face OCT microleakage investigation after laser-assisted dental hard tissue treatment

Purpose: To investigate using en-face Optical Coherence Tomography (OCT) the microleakage after Er:YAG laser cavity preparation. Material and Methods: Thirty single- and multi-rooted freshly extracted human teeth divided into two study groups, group I (laser) and group II (control), were used in this study. In group I, Class V cavities were prepared using laser on the buccal surface of each tooth. The laser device used was an Er:YAG laser (2940 nm, VSP, 250-320 mJ, 10-20 Hz). In group II, cavities were prepared conventionally and acid etched on the oral surface of the same tooth. All cavities were filled with composite resin. The cavity microleakage was investigated using en-face Optical Coherence Tomography prototype, based on transverse scanning and operating at 1300 nm. Results: The investigation demonstrated qualitatively the reduction of microleakage in cavities prepared with Er:YAG laser as compared to the control group, in which cavities were prepared conventionally. Conclusion: The en-face OCT method provided a superior non-invasive and real time investigation method, thus reducing the occurrence of secondary caries by early detection. Moreover, based on the results of this investigation, it may be concluded that Er:YAG laser-assisted cavity preparation leads to reduction of microleakage.