InLab and Cerec Connect: Virtual Contacts in Maximum Intercuspation Compared with Original Contacts - An In Vitro Study

Purpose: The aim of this in-vitro study was to evaluate the accuracy of inLab and Cerec Connect software in simulating the maximum intercuspal contacts in comparison to the real situation on the respective gypsum casts. Materials and Methods: Ten pairs of maxillary and mandibular casts were mounted in articulators in maximum intercuspal position. The contacts of the gypsum casts were marked and digital photographs of the mandibular casts were taken. Digital impressions of arches were made using two different software packages; inLab (Version 3.83) and Cerec Connect (Version 3.83) using the Cerec Acquisition Center. The intercuspal position of the teeth was captured by buccal images. Screenshots of the virtual casts showing the occlusal contacts were saved. The digital photographs of the contacts of the cast and the screenshots of the occlusal contacts were superimposed using an image processing program. The number of contacts of the virtual mandibular models that were identical with the contacts of the gypsum casts were determined and calculated as percentages in relation to the gypsum cast contacts, which were set as 100%. The null hypothesis tested was that the Cerec connect software delivers contacts that are closer to the real situation than contacts created with the inLab software. Results: Cerec Connect showed a median percentage of 41.6% and Inlab a median percentage of 31.9%. The Wilcoxon test revealed statistically significant differences between the inLab software and Cerec Connect. Especially at the contra-lateral side of that side where the virtual buccal registration was done, the contacts showed the greatest deviations from the original. Conclusion: Cerec Connect more precisely virtually simulated the real contacts than did inLab when scanning fullarch dentitions. Keywords: inLab, Cerec Connect, buccal image method, maximum intercuspal position, occlusal contact, virtual occlusal contact