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"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 μm. The same samples were analyzed by
using a micro-computed tomography (μCT) 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
μm, 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 μCT images. The SS-OCT system allows for an efficient
evaluation of biomimetic Tizian "table tops".
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