This study aimed to construct throe-dimensional finite element model of the mandibular complete overdenturo and to analyze the influence rules for stress distribution under different mandibular shapes. The layer cutting method was employed as a basic tool to deal with different plaster models to gain two-dimensional point data. These data were introduced to the commercial software ANSYS to construct throe-dimensional finite element model of the mandibular complete overdenturo, including nine kinds of typical shapes, such as sharpness, roundness and squareness, and etc. Static loads were imposed on denture so as to accomplish biomechanicel analysis and to study the influence rules of stress distribution for mandibular complete overdenturo under different mandibular shapes. Results revealed that the sequence of stress from high to low was squareness, roundness, sharpness and the other extrapolated, basic and inside. The throe-dimensional finite element model has high simulation accuracy and the results provide an experimental foundation and guidance for clinical work.

Objective To explore the application and effect of case-based learning(CBL)in vas-cular surgery clinical teaching. Methods Totally 37 resident doctors were randomly divided into 2 groups respectively: CBL teaching group (n=21)and traditional teaching group (n=16). CBL teaching was con-ducted through the following procedures:selecting typical cases-establishing and applying typical case library-autonomous learning-holding regular seminars. Traditional teaching was conducted through the following procedures: basic theory studying-participating in clinical practice-participating in case discus-sion. Evaluation was conducted based on test socre (written test and clinical operational skill test)and res-idents' feedback of teaching effect. Data were statistically described and independent sample t test was performed. Results Theoretical exam score and clinical skill test score were high in CBL group than in traditional group ((thoretical score:(85.53 ±1.75) vs. (79.94 ±2.29);clinical skill test score:(85.10±1.64)vs.(80.31±1.82)). CBL teaching group had advantages in improving learning efficiency, cultivat-ing clinical thinking,promoting mastery and application of knowledge,broadening knowledge, promoting communication and expression ability and improving study enthusiasm ,et al . Conclusion CBL teaching can effectively improve the teaching quality and obtain higher evaluation. Typical case li-brary should be constantly improved and education of vascular surgical basic theory should be strength-ened to promote CBL.

Objective To explore the effects of rehabilitation for adult cervical spinal cord injury without radiological abnormality. Methods 80 patients were studied retrospectively. Results The increase of motor score of anterior, posterior and conservative group were around 5, 2 and 2, whereas that of FIM were 11, 17 and 15, respectively. The changes of sensory score were uncertain.Conclusion The effect of surgical or conservative treatment is limited on neurological recovery, while rehabilitation can bring more functional independence to patients with cervical spinal cord injury without radiological abnormality.