Biomimetic Tizian "table tops" analyzed with swept source optical coherence tomography

Table tops/occlusal veneers are partial crowns that allow for the biomimetic restoration of worn teeth in bruxing patients. The biomimetic approach includes a CAD/CAM composite resin for the manufacturing of the "table tops", for example Tizian, which is a zirconia reinforced composite (Schutz Dental Group). In the present study we prove the value of a fast swept source optical coherence tomography (SS-OCT) system in the evaluation of the marginal fit of Tizian "table tops". 12 maxillary first premolars were extracted and minimally invasive prepared for "table tops". The Tizian "table tops" were then adhesively cemented on the natural teeth with Variolink II (Ivoclar Vivadent). A SS-OCT system has been used to evaluate the marginal and internal adaptation of Tizian "table tops". The SS (Axsun Technologies, Billerica, MA) has a central wavelength of 1060 nm, a sweeping range 106 nm (quoted at 10 dB), and a 100 kHz line rate. The depth resolution of the system, measured experimentally in air was 10 mu m. The same samples were analyzed by using a micro-computed tomography (mu CT) system, in order cu confirm the data obtained by using OCT. The imaging system used for this study offers good spatial resolutions in both directions, transversal and longitudinal, of around 10 mu m, a high sensitivity, and it is also able to acquire entire 3D volumes as fast as 2.5 s. Once the full dataset has been acquired, rendered high resolutions en-face projections could be produced. With it, the "table top" - cement - abutment tooth interfaces were observed on both C-scans as 2D images and also in the 3D reconstructions; the system was able to detect several open interfaces, which were confirmed on the mu CT images. The SS-OCT system allows for an efficient evaluation of biomimetic Tizian "table tops".