3D Morphological Measurements of Dental Casts with Occlusal Relationship using Microfocus X-ray CT

Abstract

In the diagnosis of dental occlusion, it is necessary to quantitatively measure interocclusal contacts and transfer them to a computer model. In this aspect, three-dimensional computer models of upper and lower dental casts play a significant role. In this study, we proposed a new method to measure occlusal interaction by using a microfocus X-ray CT technique. Measurement accuracy was determined as ±0.03 mm in comparison with a coordinate measuring machine. A superimposition procedure for two sets of three-dimensional dental cast models was also established. Using the same dental cast, the standard deviation between the two sets of models was ±0.015 mm -which was defined as measurement precision. Between an optical laser scanner and the microfocus X-ray CT system, the standard deviation measured between the two models was ±0.05 mm. Data were acquired when upper and lower dental casts mounted on the bite impression were scanned, and then occlusal interaction, contacts, and distance distribution between the casts were visualized by a colored map on the cast models. Within the limitations of the current study, it was successfully demonstrated that microfocus Xray CT was well poised for quantitative measurement of occlusal interaction.

Pilotstudie zur Genauigkeit und Dimensionsstabilität von Abformmaterialien mittels industrieller CT-Messungen

“…Diese Aussage verdeutlicht wiederum die Abhängigkeit der elektronischen Objektabtastung von den Materialeigenschaften des verwendeten Abformmaterials. Erste Studien von Kamegawa et al zeigten anhand von CT-Untersuchungen zudem, dass okklusale Beziehungen mit dieser Untersuchungsmethodik quantitativ gut beurteilt werden können [14,15].…”

“…The first studies conducted by Kamegawa et al using CT also showed that occlusal relationships can be assessed to a high standard with this examination method [14,15].…”

A Technique for Digital Impression and Bite Registration for a Single Edentulous Arch

“…Very few reports have been published regarding the application of digital technology for the process of impression and interocclusal recording in edentulous patients. When using digital technology for the process of interocclusal recording, a common technique included additionally scanning an interocclusal record whose negative could then be used to correctly align both arches . Interocclusal records, due to their dimension and elasticity, were bound to introduce errors when used to align the maxilla and mandible .…”

Investigation of the effects of storage time on the dimensional accuracy of impression materials using cone beam computed tomography

“…They evaluated its reliability and found similar differences between CT scanning and manual measurements on plaster models. Kamegawa et al28 compared the accuracy evaluation using a microfocus X-ray CT technique and a conventional 3D optical scanner. The microfocus X-ray CT provided sufficient accuracy in dental occlusion diagnosis and quantitative clinical assessment of occlusal treatment 29…”