Studys On Dento-facial Features In Xinjiang Kazak With Normal Occlusion-Computer Assisted

Norms with derivation of dentoficial structures constitute the fundamental upon which orthodontic reserches are based,so as to make out correct dianosis and treatment plan after the mechanism of various malocclution being comprehensively analyed.Variations exist in the features of teeth, jaws and maxcillofacial strctures of the populations of various races, nationalities and regions. The norms for a special population are often considered abnormal or different at least as it used to anther, which forms the destine to establish norm standards for special population in order to have malocclution of different races, nationalities and regions successfully treated.Sinces 1950's, many domestic and abroad reserches have been carried out on the normal features of teeth, jaws and maxilloficial structures of different races, nationalities and regions, with the normal values established for each race and region involved.This study was carried out on the features of dento-facial structures in 82 Kazaks at the age of 12-16 years old. Normal occlution was the racial standard for the objects being screened. The methodology involved X-ray cephalomitrical analysis on hard tissues, with multiple normal values of the teeth, jaws and maxillofacial structures concerned and their interalation had been comprehensively analyzed. At the same time, computer asistied were used, it can be improve the efficiency andprecisely. The results are desmonstrated as followed:1. Outcomes of the X-ray cephalomitrical analysis on hard tissues in kazak with normal occlusion at permanent dentition stages were established.2. Gender deffrences were significantly shown in liner measurements, with the male's being larger in general. Most of the angular items were seen similar without significant diffrence between males and females, except the anterior craniobase plane showing steeper in female than male.3. Compared with the population of Han Nationality, Kazak showed a recessed maxilla and forward contra-clockwise rotation of mandibular, featuring straight facial pattern towaeds classIII.4. The reliability of the reference plane SN was preliminarily concerned, with the conclution coming out as a suggestion that items related with the SN plane have to be revised in case SN plane is more steep and upright ,or the reference plane FH becomes the better choise.From all the mentioned above results obtained in this study, the conclution comes out to be that the dental-facial structures vary with significance among different races and nationalities. Norms of each nationality and region have to be established to match the need of clinical treatments of Orthodontics.