Evaluation of marginal gap of lithium disilicate glass ceramic crowns with optical coherence tomography.

Marginal gap (MG) was the most important factor to evaluate the success of crowns. The study was to assess the MG of lithium disilicate glass ceramic crowns with spectral domain optical coherence tomography (OCT) and stereomicroscopy in vitro, and to provide evidence to measure the MG with OCT. Consistency was observed between OCT and stereomicroscopy to measure the MG after cementation. There was no significant difference between the MG of lithium disilicate glass ceramic crowns using OCT and stereomicroscopy (OCT 59.55  ±  7.22  μm, stereomicroscope 59.48  ±  6.53  μm, P  =  0.736) after cementation. OCT was a noninvasive diagnostic technique to measure the MG of lithium disilicate glass ceramic crowns. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).