Measurement of occlusal contact area using BiteEye

A material for checking accuracy of fit (Blue Silicone®; GC, Tokyo, Japan) was used to examine the occlusal contact in the intercuspal position. The occlusal contact area was measured once at each clenching strength (20, 40, and 60 % MVC) using visual feedback. Subject posture was the same as during Prescale measurement. Subjects were instructed to open their mouths one finger width and Blue Silicon was inserted above the lower row of teeth, and subjects were then instructed to keep it in the mouth for 15 s. Subjects were instructed to keep the clenching strength of provisions while displaying the strength clenching on the monitor. Subjects clenched their teeth at the required strength for 30 s and kept the Blue Silicone in their mouths for a further 30 s until it hardened. Taking muscle fatigue into account, measurements were taken at 5-min intervals.

Thus, the Blue Silicone impressions obtained were examined using a BiteEye occlusal contact analyzer (BiteEye-I®; GC, Tokyo, Japan). The thickness of the Blue Silicone film at the points of occlusal contact was set at 10, 20, and 30 μm, and the occlusal contact area was calculated. When the thickness of the Blue Silicone film at the points of occlusal contact was set at 10 μm, Dental Prescale and Blue Silicone approximate in the occlusal contact area in the natural dentition.

While there have been studies in which the occlusal contact area was calculated from the silicone method, the thickness of silicone (μm) that is defined as occlusion has not been quantitatively clarified. Okada et al. found functional occlusal contacts can be recorded at the silicone thickness 30 μm. From the above sentence, the thickness of the Blue Silicone film at the points of occlusal contact was set at 10–30 μm.