A radiographic interpretation of cranio-facial reference lines in relation to prosthodontic plane orientation.

Abstract

AbstractAn analysis was made of prosthodontically related cranio‐facial reference lines and angles of lateral skull radiographs taken for 60 edentulous Chinese adults wearing newly fabricated dentures.The radiographic angle between the Frankfort horizontal line and Camper's line was compared across Chinese and Swedish male adults. This showed a significant increase in mean angle of 3.4° for Chinese subjects. The angular difference was explained on the basis of ethnic variation in ‘orbitale’ position which could probably account for the relative steepness of the Frankfort horizontal line in the Chinese.The plane of orientation in the edentulous subject was made to conform to the ala‐tragus line. The ala‐tragus line in Chinese adults was observed radiographically to orient itself at a comparatively steep angle to the horizontal plane of the articulator.The variation in ‘orbitale’ position and the influence of a steep occlusal plane in the edentulous Chinese could impose a limit to the smooth transfer of the facebow registration of the maxillary occlusal plane to the articulator.