Three-dimensional Analysis Of Palatal Growth In Deciduous Anterior Crossbite Malocclusion Comparing With Normal Occlusion

Malocclusion is often accompanied by varying degrees of skeletal disharmonies. Human body is a precise functional complex. Its morphology is guided by not only genetic factors, but also the surrounding environment and the external mechanical load.In this paper, we discussed palatal morphologic change of one-dimensional measurement data, two-dimensional growth curve, and three-dimensional growth surface along time axis. The whole paper was divided into three parts:1. Analysis of palatal growth in the normal deciduous dentition. The maxillary dental casts of children with normal deciduous occlusion were as sample in this study. Palatal shape was fitted by a mathematical equation in the frontal and sagittal planes. Palatal width, length, height, slope, as well as intercanine distance were computed. All palatal data were evaluated by age and gender. The result showed that: Palatal shape and size were influenced by age and gender in three-dimensions. The characteristic of change is the faster anterior-posterior speed in deciduous dentition. 2. Analysis of palatal growth in the deciduous anterior crossbite dentition. Patients with deciduous anterior crossbite malocclusion were used as samples in this study. Palatal growth curve was fitted in the frontal and sagittal planes. Palatal 3D data were computed and evaluated by age and gender. The result showed that: Although malocclusion children's palate has a certain degree of development, the speed is more inactive in comparison with normal occlusion. The gentle variation of palate shape was only presented in 3-4 years. The obvious length growth is restricted, the potential width development is lack ,so that form of compensation tended to the development of vertical dimension.3. Palatal three-dimensional morphological analysis in deciduous anterior crossbite malocclusion comparing with normal deciduous occlusion. Girls with deciduous anterior crossbite malocclusion were as sample and compared with those who exhibiting normal occlusion. Palatal growth fitting curve and surface from 3 to 5 years were compaired respectively. The result showed that: the anterior crossbite children had more narrow and higher palatal vaults. The palatal A-P growth was restricted, and the asymmetric shape was more obvious. Compared with normal occlusion, although the distribution of malocclusion children's palatal surface rebuilding was similar to the normal's counterpart, the speed was slower.This article compared the palatal growth characteristic of deciduous anterior crossbite children with the normal occlusion children, in order to investigate relationship between skeletal disharmonies and malocclusion. On this basis the necessity of anterior crossbite early treatment was well ilustrated.