Objective: To investigate the relationship of the terminal position of the muscular contraction path and centric relation position with different vertical dimension.Methods: The terminal position of the muscular contraction path and centric relation position with different vertical dimension were recorded for ten edentulous patients with gothic arch.Results: The mesial distance between the terminal position of the muscular contraction path and centric relation position increased with the vertical dimension.The lateral dimension between the terminal position of the muscular contraction path and centric relation position,the distribution of the terminal position of the muscular contraction path are not correlated to the vertical dimension.The center of the terminal position of the muscular contraction path is 1-4 mm ahead of the centric relation position and(0.42?0.47) mm lateral to the centric relation position.The distribution of the terminal position of the muscular contraction path is(1.36?0.58) mm in the mesial-distal direction,(1.56?0.62) mm in the lateral direction.Conclusion: With the increase of the vertical dimension,the mesial distance between the terminal position of the muscular contraction path and centric relation position increased.

BACKGROUND:The location of residual dentin may affect stress distribution of tooth root. ＜br> OBJECTIVE:To make a three-dimensional finite element analysis of gold al oy post-core and al-ceramic crown in the repair of structure defects of the mandibular first molar, and to provide a guideline for planning restoration for such kind of tooth structure defects. ＜br> METHODS:Three-dimensional finite element models of the restored first mandibular molars were constructed by CT image reconstruction technique. Then MIMICS software was used to separate the areas and finish the three-dimensional calculation. GEOMAGIC software was also applied to modify and generate a NURBS surface in each patch. Al components of the models were assembled under the ANSYS preprocessor. The Mohr strength theory was applied for comparing the maximum Mohr stress value of dentin and stress concentration areas in six models under different simulating loads. ＜br> RESULTS AND CONCLUSION:The restoration effects in six models were compared, the maximum Mohr stress value of dentin and stress concentration areas were not obviously different. The location of residual dentin has little influence on the stress value and distribution, when restored by gold al oy post-core and and al-ceramic crown.

0.05).The expression began to increase around the infarction at 12h reperfusion,it reached the peak at the 3th day in the boundary zone and then it gradually decreased.Conclusion The overexpression of IL 6 played an important role in the course of cerebral ischemic reperfusion, and could damage the brain tissue.

Objective\ To explore the risk factors of dementia induced by stroke.Methods\ 258 elder patients with stroke had been followed up for three months,including clinical neuropathy and neuropsychological tests.Multivariate noncondition stepwise Logistic model analysis was made after single variable analysis.Results\ There were 83 patients with dementia induced by stroke,175 patients without dementia after stroke.The morbidity was 32.2%.The following eight factors were associated with dementia i.e.,age,multiple lesions,left lesion,large area of cerebral hemorrhage or cerebral infarction,cerebral atrophy,hypertension,the history of stroke,and bilateral lesions.Conclusions\ Dementia induced by stroke is caused by multiple factors.It is closely correlated to numbers of cerebral lesions,the location of cerebral lesions and the size of brain tissue necrosis.The primary conditions of patients'cerebral function are also closely associated with the occurence of dementia.

Objective To explore the differences between the minority nationality and Han recruits in army occupational adaptability.Methods 3 213 recruited youths coming from 29 autonomous counties of minority nationalities,Yunnan Province were tested by 2011 Chinese enrollment psychological test system to explore the differences of the intelligence adaptability and character trait adaptability between the minority nationality and Han recruits.Results There were obvious differences in the eligible rates of intelligence and character trait between minority nationality and Han recruits ( x2 =13.3,9.0; P ＜ 0.01 ).The intelligence eligible rates of Yi,Hani,Wa recruits (78.1％,76.8％,68.2％,respectively) were significantly lower than those of Han recruits (84.0％) (P＜0.01 ),and time used in three intelligence test was all significantly longer than Han recruits(P ＜ 0.05 ).Naxi and Dai recruits' time used in word reasoning ( ( 109.2 ± 20.9) s; ( 123.9 ± 32.5 ) s,respectively) was both longer than Han recruits' (P＜0.01).In the fact of character trait,the eligible rates of Hani,Wa recruits (67.8％,64.3％,respectively) were significantly lower than that of Han recruits (78.1％) (P ＜ 0.01 ).The Hani average score of T dimension (57.9 ± 17.5) was obviously higher than the Han's score (52.2 ± 16.5) (P ＜ 0.05 ).All dimensions average scores except T and D dimension of Wa recruits were all significantly higher than those in Han recruits(P ＜ 0.05 ).Conclusion Every minority nationality has its unique differences in armyoccupational adaptability from Han.Ethnic factor may be an important reference for new recruits' selection,education and management.

Our experiment aims to compare the effects of "energy-containing lactated Ringer's solution"(EL-RS) with those of "lactated Ringer's solution" (LRS) as an initial resuscitation fluid for the treatment of traumatic shock in rabbits. Deep shock animal models were produced in 74 adult rabbits using the method of pincers pressure and Wiggers' hemorrhagic shock method to produce crush injury of the soft tissue on the thigh and comminuted fracture of the femur. Results showed that blood pressure of the experimental group rose more rapidly than control group and the survival time of the former were longer than the later. The lowering of serum lactate and blood pH etc. showed a similar difference. It is suggested that ELRS is more efficient than LRS for the treatment of traumatic shock in rabbits.

Objective To establish the examination criteria for the prosthodontic clinical practice using Delphi method,to improve the evaluation level of clinical practice of dental students.Method 15 clinical experts in the department of prosthodontics,Peking University School of Stomatology were selected in this study.The evaluation indicators system of prosthodontic clinical practice was established by two rounds of investigations by Delphi method.Initiative ratio and authority coefficient (Cr) of the experts were used to evaluate the reliability of the new examination criteria.Next,the eight-year program students in class of 2007 (38 students) and 2008 (34 students) were examined by old and new examination criteria respectively and the feedback of the students were collected by the method of questionnaire.SPSS 16.0 was used for data processing.Results In this study,the initiative and the authority of the experts was very high,and the initiative ratio and authority coefficient were 100％ and 0.860 respectively.A new examination criterion of prosthodontic clinical practice was established,including 3 first-level indicators,9 second-level indicators and 19 third-level indicators.Questionnaire analysis revealed that only 12％ (n=4) and 9％ (n=3)of the students in class of 2008 considered the new examination criteria was not comprehensive enough or objective enough,which was obviously less than the students in class of 2007 [45％ (n=17) and 36％ (n=14)].Conclusion A new examination criterion of prosthodontic clinical practice was successfully established by Delphi method.The new examination criterion is more comprehensive and objective than the old one and can promote the educational quality of clinical practice of dental students.The method of this study also provides reference for the educational reform of clinical practice in other fields.

In this study Na2HPO4-Ca(NO3)2 system was used to synthesize hydroxyapatite (HA). Its synthetical method was simple and low in cost. With the physical-chemical characteristic observation and the animal experimentit was proved that HA was pure, with pores ranging from 20 to 200 ?m in diameter.The chemical structure of HA was similar to that of inorganic part of bones.An investigation of the histological changes and osteogenetic effectiveness of HA implanted was conducted and the mechanism of HA osteogenetic effectiveness is discussed. The study will provide scientific basis for the clinical use of HA as bone graft substitute.

Sciatic neurectomy was performed on the right limb in 30 rats divided into three groups. On the first postoperative days, stainless steel capacitor plates were applied parallel to each other over the midtibial region of the right, neurectomized limb m each animal in the latter two groups, which were stimulated continuously with a 60kHz sinawave signal delivering 5-10V from peak to peak. The first group was served as controls and received no electrical stimulation. At the completion of 12d of electrical stimulation, all rats were sacrificed. A statistically significant enhancement of wet weight, dry weight, ashed weight, ultimate strength and bone density occurred in the stimulated, denervated tibiae of the experimental animals compared with the nonstimulated, denervated tibiae of the control animals. The results show that a sciatic neurectomized osteoporosis was prevented in the tibiae by a capacitively coupled electrical field.

OBJECTIVEThe aim of this study was to compare the mandibular position when speaking with the intercuspal position and to check the stability of phonetics when determining the horizontal jaw relation in healthy adults.

METHODSA total of 19 healthy volunteers were recruited. Seven Chinese letters, namely, /xi/, /er/, /yi/, /ci/, /mi/, /ni/, and /ri/, were chosen in the test. O-bite was used to record the mandibular position when speaking these letters. A full-adjusted articulator was used to find the mandibular position during speech, and the mandibular position was measured using a vernier caliper. The mandibular position during speech with intercuspal position was compared in both anterior-posterior and left-right directions of the horizontal plane. Multi-factor analysis of variance was conducted for the statistical analysis of the effect of objects and letters on the mandibular position.

RESULTS1) The mandibular position was in front of the intercuspal occlusion position when speaking all seven letters, and almost no deviation was observed in the left and right directions (the mandibular position value of 82% was in the range of 0.5 mm). 2) Different objects had different mandibular positions during speech, whereas different letters did not. The distance between the centric relation position and the intercuspal position had a positive correlation with the range of the mandibular position during speech.

CONCLUSIONThe mandibular position was in front of the intercuspal position when speaking all seven words in the test. In the same object, the mandibular position was stable during speech.