| Cephalometrics was an important means in the clinical diagnosis, treatment planning and study in orthodontics. Coben analysis and McNamara analysis were kinds of cephalometric analyses mainly focusing on distance measuring between points and lines to disclose the relationships among teeth and bones, which could supply valuable evidences for the diagnosis, treatment planning and study of malocclusion. These kinds of cephalometic analyses were more visual and understandable comparing with Angle analysis.The study would set up normal values of Coben analysis and McNamara analysis for Changchun children with normal occlusion, construct multangular charts, and even develop computer assisting diagnosis software to discuss the regional features of craniofacial growth which could supply academic basis and assistant tools for diagnosis and treatment of malocclusion.In 1931 Broadbent and Hofrath introduced the cephalometric analysis, which was to trace the radiograph, fix on some points, and measure certain distances, Angles and rates to learn the relationships among constructions of skull bone, maxillary bone, facial bone and teeth tissue. Depending on the analysis, the mechanism, feature and position of malocclusion were found out which was in favor of correct diagnosis and treatment planning. Measuring analysis before and after the treatment could discover the changes of craniofacial constructions in the treatment process, which would help us study the mechanism of orthodontic appliance and the stability and recrudesce after the treatment. Cephalometic analysis was also a common method to study the craniofacial growth of children. In the past tens of years, cephalometic analysis always played an important role in the clinical diagnosis, treatment planning and study in orthodontics.From 40s to the end of 50s in this century, orthodontists introduced tens of cephalometric analyses such as Tweed, Wylie, Downs, Steiner, Reidel and Ricketts analysis for the craniofacial analysis and malocclusion diagnosis. Firstly, normal values of normal occlusion and craniofacial construction were obtained to compare with the abnormal occlusion and craniofacial construction. Because of the racial differences among countries, respective normal values of countries and individual nations were constructed. Hence, cephalometrics developed fast and became an important method in the diagnosis and study of stomatology. Now the most common cephalometric analyses are Tweed, Downs, Steiner analysis and so on。Angle Class III was a kind of common malocclusion in clinical work. As the statistic data of Chinese Stomatology Association in 2000 showed, the incidence of Angle Class III in deciduous dentition, mix dentition and permanent dentition were 14.94%,9.65% and 14.98% respectively, which were higher than those of the western, but close to those of Japanese. Angle Class III influenced the oral function, facial esthetic, and psychological health of patients, and developed along with the age. So more attentions of orthodontists were paid on it.For the patients of Angle Class III with maxillary growth deficiency, maxillary protraction was applied when they were in mix dentition or early permanent dentition. Traditional analyses such as Steiner, Downs and Tweed analysis appeared their shortages in the diagnosis of maxillary growth deficiency because these kinds of analyses were mainly Angle measuring which were in short of visualization and incomplete in the craniofacial analysis.Coben analysis was a kind of distance analysis to measure the depth and height of craniofacial on the radiograph. It could analyze the craniofacial features through studying the relationships between the measuring values. Comparing with Angle analysis, Coben analysis was more visual and understandable in the diagnosis of Angle Class III developing from bones, supplying correct treatment planning, and craniofacial growth study. So it had a high value in clinical work. During the early 80s in 20 century, McNamara absorbed some theories of Ric... |
PDF Full Text Request