The Condylar Morphological Characteristics And Differences Of Adolescent Different Vertical Facial Types Of Skeletal Ⅱ Malocelusions

Angle Classâ…¡malocclusion is a common malocclusion deformity, its performance are maxillary protrusion and mandibular retrognathism.Both of them are bad for facial profile of patients.Underdevelopment of mandible is the most usual reason for skeletalâ…¡malocclusions. The growth of mandible are relate to different parts. Among which the growth of Condylar process results in the growth of mandible outstandingly.Recently some study suggested that there be statistically difference between the patients with skeletalâ…¡malocclusions and normal people in mandibular body and condylar process. Some scholars of skeletal did some research on Classâ…¢patients with different vertical facial types between condylar morphology and they thought the differences exsited. There was a quesiton:whether there were differences in vertical condylar shape for classâ…¡patients with different skeletal facial types. So it is very important to investigate the relationship between the different vertical facial types and condylar morphology of skeletalâ…¡malocclusionsObjective:To compare condylar morphology, characteristics and differences by measuring the skeletal Classâ…¡panoramic radiographs of patients with condylar shape in relatively early permanent dentition in skeletal classâ…¡patients with different vertical facial types; To investigate the relationship between different vertical facial types and condylar morphology of skeletalâ…¡malocclusions for early permanent teeth, which is the guideline for the diagnosis and treatment for skeletalâ…¡malocclusion.Method:To select patients with skeletal Classâ…¡cephalometric, panoramic radiographs as a sample, Cephalometric measurements of GoGn-SN angle and the high ratio of front and behind face. The patints were divided into high angle group,average angle group and low angle group, Application of computer image analysis software were used to measure the three groups the condyle upper height, mandibular ramus height, condylar height and the width of the condylar neck. A horizontal line and a vertical line were made through the midpoint of the condylar neck respectively in order to determine the position relationship between vertices of condylar and the vertical line. All data obtained were analyzed using SPSS 11.0 software.Result:There was no statistical difference in condylar morphology with different vertical facial types of skeletalâ…¡malocclusions for early permanent teeth (p>0.05), while there was stactistical difference in the mandibular height (p<0.05), the mandibular height of Low angle group were greater than which of average angle and high angle group; There was no stactistical difference in the height of condylar morphology (p>0.05) and there was stactistical difference in the neck width of condylar morphology (p<0.05). The detal of three groups are not identical completely; known by multiple comparisons, low-angle and average-angle group differences were statistically significant (p<0.01), low-angle and high angle group difference was statistically significant (p<0.01), while average-angle and high angle group no significant differenceConclusion:1 Low-angle group of the condylar neck width is of the maximum, average angle group ranks second, and the high angle group is the smallest.2The condyle of low angle group is more inclined to the proximal end while the high angle group is more to the distal end.3 The mandibular height of Low angle group were greater than which of average angle and high angle group.