abstract |
A method of and an apparatus for making a dental set-up model utilizable in the practice of orthodontics and, more particularly, to facilitation of making the dental set-up model. The shape of an impression which is a replica of dental teeth and dental alveolar ridges of a patient is first converted on a non-contact basis into electronic data by means of a three-dimensional profile analyzer utilizing an irradiation beam. Using this electronic data and within the framework of such electronic data, representative plane defined by anatomically proximal contact points A1, anatomically distal contact points A2 and an intermediate point E between the bucco-cervical point B1 and the lingo-cervical point B2 are formed by cutting out the individual teeth. Subsequently, for each tooth, a DI line, which is a straight line connecting between the bucco-cervical point B1 and a representative point C of a cusp or edge that has been projected onto the representative plane, and a DH line intersecting the DI line perpendicularly at a point spaced a predetermined distance from the representative point C towards the dental alveolar ridge are formed. Then, the DH lines for the respective teeth are arranged on a plane along a guide line descriptive of an ideal individual dental arch form and respective heights of the DH lines for all teeth which have been lined up to a predetermined height are adjusted to a predetermined level, followed by adjustment of the angle of inclination of the representative plane for each tooth relative to a facial reference line set up on the face. |