The Study On Physiological Occlusal Characters Of Human First Maxillary Molar From Different Aged People

Several kinds of dental treatments, such as restoration for tooth caries or tooth loss, may induce the occlusal problems. Thus has come to be a subject multiply related to a lot of dental fields as Oral Physiology, Prosthodontics, Periodontics, Orthodontics, Maxillary Surgery, and so on.The clinicians frequently need to adjust the occlusal surfaces of a restoration to make it adapt the masticatory need of the patient. This is a complicated and time-costing work, which would usually result in the loss of esthetic figure and occlusal osculation of natural tooth. Therefore, it is of interest to evaluate the physiological occlusal characters of different aged people, which may do great help for the technician to design and manufacture the restoration. The study may also provide valuable references to clinicians when they need to treat the patients with occlusal problems.This study can be divided into two parts:1,The original occlusal data of first maxillary molar have been obtained using 3D scanner., The effect of attrition on the occlusal situation and the variety of occlusal changing of maxillary first molar from different aged people were evaluated under the help of three dimensional software, Imageware 12.0, and VC++ 6.0.2,The Intercuspal positions (ICP) of bilateral molars were precisely recorded using silicone rubber impression material when candidates bite tightly. Then the condition of occlusal contact was reproduced by color-register in the lab. The distributions of the main functional zones of first maxillary molar were observed under stereomicroscope.The occlusal situations of maxillary first molar from different aged people at both rest and functional status were evaluated in this present study. The following results and conclusions could be obtained:1. As the age of tested person increasing, the high points of occlusal surfaces of maxillary first molars were moved toward the mesial direction. The clinicians should modify the occlusal condition of restorations for different patients according to their age.2. The numbers of occlusal points recorded for groups of teenager, youth, and mild-aged people were 233, 144 , and 127 respectively, which was decreasing when the age of tested objects increased3,Regardless of the effect of age, the male has more the numbers of occlusal points in male group were significant higher than that in females group.4. The main functional zones of juvenile group dispersedly distributed in the middle first three of lingual surface, middle fossa, and distal cusp The main functional zones of youth group and middle-aged group distributed in middle first three of lingual surface and middle fossa, which distributed more concentrative than that in the juvenile group.