Setting the Sagittal Condylar Inclination on a Virtual Articulator Using Intraoral Scan of Protrusive Interocclusal Position and Cone Beam Computed Tomography

Abstract

The articulator is a prerequisite device for the analysis of occlusion and prosthodontic treatment, and it is required to simulate patient jaw movements. This article describes the technique to obtain sagittal condylar inclination (SCI) using cone beam computed tomography (CBCT) data and intraoral scan of the protrusive interocclusal position. The SCI can be used on a virtual articulator in a computer-aided design software, and it can assist in the fabrication of prosthesis which is harmonious with the mandibular movement of individual patient.

A Novel Technique to Align the Intraoral Scans to the Virtual Articulator and Set the Patient‐Specific Sagittal Condylar Inclination

“…To simulate individual jaw movements, patient‐specific parameters must be delivered to program the virtual articulator, among which SCI is an important value 3,12 . This is defined as the angle formed between the protrusive condylar path and the FH plane 3 . Conventionally, average values of the SCI are utilized when an intraoral scanner is employed.…”

“…As dental treatments are marching toward a digital era, precisely reproducing patients’ jaw movements in the virtual environment by accurately relating the scanned arches to the virtual articulator and individually setting its parameters according to the patients’ condyles is critical for making individualized diagnosis and treatment planning, as well as achieving good multidisciplinary treatment and restoration fabrication 1–3 . Conventionally, a facebow and bite registration are used to physically mount the stone casts on a mechanical articulator, and a protrusive interocclusal record is also needed to program the articulator; then the mounted casts will be transferred to the virtual environment by using a laboratory scanner 4,5 .…”

“…The method of measuring the SCI by using a mechanical articulator and a protrusive record was first introduced by Christensen in 1905 15 . Then Seoung‐Jin et al proposed a digital SCI obtaining technique by using intraoral scan and CBCT scan 3 . However, an additional 3D analysis software program is still needed, which has limited its utilization in the dental CAD software.…”

Virtual Articulators and Virtual Mounting Procedures: Where Do We Stand?

“…3) The MS VA is an average value articulator common in daily digital practice, but needs additional settings to facilitate the CAD and CAM phases. Sagittal condylar inclination (SCI) is an important value for oral rehabilitation, defined as the angle formed between the protrusive condylar path and the Frankfort plane 54 . Recently, a procedure has been reported for obtaining patient‐specific SCI using data acquired from CBCT imaging and intraoral scanning of the protrusive interocclusal position, which can be implemented during VA assembly 54 .…”

“…Sagittal condylar inclination (SCI) is an important value for oral rehabilitation, defined as the angle formed between the protrusive condylar path and the Frankfort plane 54 . Recently, a procedure has been reported for obtaining patient‐specific SCI using data acquired from CBCT imaging and intraoral scanning of the protrusive interocclusal position, which can be implemented during VA assembly 54 . Further studies should be conducted to evaluate the accuracy of obtaining individual parameters needed to adjust the settings of the MS type.…”