A STUDY ON THE ANALYSIS OF THE CURVE OF SPEE ON THE GNATHOLOGICAL CAST AND THE CEPHALOMETRIC RADIOGRAPH

Choi, Ah Young; Kim, Jeong Sun; Kay, Kee Sung

Abstract

Clinically, the curve of Spee is widely applied as a determined level of the occlusal curvature when the oral rehabilitation and the reconstruction of the prosthesis is needed at the malalignment dentition due to the missing, extrusion, and the inclination of the teeth. The purpose of this study was to analyze the curve of Spee of the occlusal curvature which influences to the occlusal form and the location three dimensionally, and then was to measure the radius and the degree of curvature of the curve of Spee and also was to investigate the influence to the cuspal inclination according to the change of the inclination of the curve of Spee which was analyzed by AutoCAD R.13 program at the gnathological cast and the cephalometric radiograph. The following results were obtained : 1. The radius of the curve of Spee was the mean of 11.74+/-3.64cm in the model, 12.75+/-4.63cm in the radiograph and there was no significant difference statistically between the model and the radiograph(P >0.001). 2. The radius and the degree of curvature of the curve of Spee showed negative correlation(r=-0.80), while the radius and the degree of curvature of the curve of Spee in relation to the length of the curve of Spee did not show correlation. 3. The case of the curve of Spee inclined to the posterior, that is, Post.Mtheta group showed the mean of 4.73+/-3.64 , positive cerrelation to the P2m, M1mm, M1dm, M2dm, and especially the greatest correlation coefficient to the mesial inclination angle of the mesio-buccal cusp tip of the first molar(r=0.70). 4. The case of the curve of Spee inclined to the anterior, that is, Ant.Mtheta group showed the mean of 3.28+/-3.59, positive cerrelation to the P2m, M1mm, and also the greatest correlation coefficient to the mesial inclination angle of the mesio-buccal cusp tip of the first molar(r=0.78)