Planmeca Oy

Planmed Oy

Jaakko Lähelmä

Kustaa Nyholm

Tapio Laukkanen

Pentti Hyvärinen

Leo Aspelund

Jukka Kanerva

Mikko Lilja

Kalle Karhu

Ari Hietanen

Sakari Kettunen

Timo MÜLLER

Henri Veisterä

To create a digital surface model of an intra-oral anatomy, a recess or a hole in an impression material having a predetermined shape and size is scanned. The scanning results and information on the predetermined shape and size are used for determining a threshold value representing interface between the impression material and another material. The threshold value is then used in generating the digital surface model from CT scanning data of an impression of an intra-oral anatomy on said impression material.

Dental surface models

The invention relates to a medical computed tomography apparatus which includes a support construction () supporting a substantially ring-shaped O-arm (), which in turn supports imaging means (). The cross-section of the outer cover () of the O-arm in a direction perpendicular with respect to the central axis of said ring-shaped structure () is for its prevailing portion arranged substantially of the shape of an arch of a circle but to comprise a cut, and within the sector covered by the cut the distance from the center of said arch of a circle to the edge of the outer cover () is shorter than within said portion of the outer cover () substantially of the shape of an arch of a circle. As to the examination opening (), it is arranged for its prevailing portion substantially of the shape of an arch of a circle but to comprise an extension, and within the sector covered by the extension the distance from the center of said arch of a circle to the edge of the examination opening () is longer than within said prevailing portion of the examination opening () substantially of the shape of an arch of a circle. The imaging means () are arranged to be moved within the O-arm at different distances from their center of rotation.

Medical computed tomography imaging apparatus

Growing community of inventors

Helsinki, Finland

Jaakko Lähelmä