Objective The measurement of normal tibia was aimed to obtain the value of the posterior slope angle of the medial tibial plateau in Chinese adult and its related parameters in order to improve the design of knee prosthesis more suitable for Chinese people, and also provide an essential features of tibia for resecting tibial plateau in total knee arthroplasty. Methods 450 knees of 428 persons which were healthy Chinese adult long living in North China, were 252 male knees and 198 female knees with an average age of 43.9 years ranging from 18 to 79 years. The criteria of the subjects were no tibial deformity, no genu varum and valgum, abnormal changes of articular surface, and had sustained ever any tibial trauma. Depending on the age of subjects, they were divided into three groups, group A was between 18 and 39 years, group B between 40 to 59 years, and group C more than 60 years. Moreover, 6 tibias harvested from healthy Chinese corpses were measured as well. Computer radiography was used to take standard lateral aspect of X-ray film. The imagines were stored into computer by scanning the films, and so the measurement was taken in computer using Danzig method. The data were analyzed statistically. Results By two factors analysis, the sex and age had no significant influence of the posterior slope angle of the tibia; furthermore, the angle was not different between the left and right tibia. In male adult, the average degrees of left posterior slope angle of the medial tibial plateau were 13.2??4.4?, the right 10.5??5.1?, and the average degrees of posterior slope angle of both sides were 11.7??4.9?. In female adult, the average degrees of left posterior slope angle of the medial tibial plateau were 11.2??3.5?, the right 10.6??4.4?, and the average degrees of posterior slope angle of both sides were 10.8??4.0?. The average degree of group A were 11.7??4.4?, group B 10.4??4.7?, group C 12.3??4.4?. In summary, there was no significant difference of posterior slope angle of the medial tibial plateau between sex, side and age. Conclusion The average degrees of posterior slope angle of the medial tibial plateau in North China adult were 11.3??4.5? ranging from 0??21? to 9?-13?, and were larger than that of the Westerns.

[Objective]To measure the posterior sloope angle of proximal tibial medial meniscus(PSAPTMM) in Chinese adult,provide parameters for improving the design of knee prosthesis more suitable for Chinese and for resecting tibial plateau in total knee arthroplasty.[Method]Sixty-three male knees and 52 female knees of Chinese,without tibial deformity,genu varum and valgum,abnormal change of articular surface,and tibial trauma,with average age of 45.6 years(ranged,20~74 years,were divided into 3 groups according to persons age: group A,18~39 years;group B,40~50 years;group C,more than 60 years.The sagital tomography of medial meniscus of MRI were taken,stored,and measured using JENNY way.The data were analyzed statistically.[Result]By two factors analysis,the sex and age had no significant influence on PSAPTMM,and the angle was not different between the left and right knee.In male adult,the average degree of left PSAPTMM was(2.7?1.8,of the right(2.9?1.7)? with an average degree of both sides of(2.9?1.8.In female adult,the average degree of left PSAPTMM was(3.5?1.7,of the right(2.8?1.6,with the average degree of both sides(3.2?1.7.The average degree of group A were(3.6?1.6,group B(2.7?1.8,group C(2.8?1.7.There showed no significant difference of PSAPTMM between sex,side,and age.[Conclusion]The average degree of PSAPTMM in northern Chinese adult is(3.0?1.7,ranges from(0~6.2,and is larger than that of the westerns.

BACKGROUND:Temporary crown has been used widely in clinic. The physical properties and biological safety of temporary crown and cement materials are more superior along with the development of material science. OBJECTIVE:To summarize clinical application, physical properties and biological safety of the temporary crown and cement materials. METHODS:PubMed database was searched by the key words of temporary crown, provisional crown, temporary restoration, provisional restoration, interim restoration in English to retrieve relevant articles published from January 2004 to December 2014. Literatures addressing the temporary crown and cement materials were included, and the repetitive researches were excluded. RESULTS AND CONCLUSION:Through the clinical evaluation and experimental study, the physical properties (polymerization shrinkage, polymerization heat production, polymerization monomer release) and biological safety (cytotoxicity, irritation to the soft tissue) of the temporary crown and cement materials are the key problems needed to overcome. With the appearance of new materials and new fabrication methods, the temporary crown and adhesive materials have great application prospect and higher clinical value, but in the exploration process of the laboratory research and clinical application, there are many problems to be solved.

BACKGROUND:Chroming can improve the corrosion resistance of soft magnetic aloys. OBJECTIVE:To identify the optimal chroming conditions of two soft magnetic aloys, Fe-Cr-Mo and Fe-Ni, so as to improve their corrosion resistance. METHODS:Twelve pieces of square-shaped Fe-Cr-Mo and Fe-Ni soft magnetic aloys were casted in the size of 20 mm×20 mm×2 mm. After sanding and polishing, chrome plating was performed on these specimens and the coating thickness and hardness were measured. The selection factors included electroplate type (hexavalent chromium and trivalent chromium), current density (15, 20, 25, 35, 40, 45 A/dm2) and electroplating time (30, 40, 60 minutes). The optimal chroming conditions were determined by one-factor experimental method and the chrome plating was observed under a scanning electron microscope. RESULTS AND CONCLUSION:Cr6+ coating was significantly better than Cr3+ coating in the aspects of hardness, thickness and uniformity, indicating Cr6+ coating can significantly improve the corrosion resistance of Fe-Cr-Mo and Fe-Ni aloys. For Fe-Cr-Mo soft magnetic aloy, the optimal conditions of Cr6+ coating were as folows: current density of 45 A/dm2 and electroplating time of 60 minutes; the optimal conditions of Cr3+ coating were as folows: current density of 20 A/dm2 and electroplating time of 30 minutes. For Fe-Ni soft magnetic aloys, the optimal conditions of Cr6+ coating were as folows: current density of 35 A/dm2 and electroplating time of 60 minutes; the optimal conditions of Cr3+ coating were as folows: current density of 20 A/dm2 and electroplating time of 40 minutes.

BACKGROUND:In the comprehensive treatment of cracked teeth, the temporary protection using the orthodontic band and resin temporary crown can effectively prevent tooth fracture and protect the cracked teeth with a higher clinical success rate. OBJECTIVE:To evaluate the differences in clinical efficacy of orthodontic band and resin temporary crown on the temporary protection of cracked teeth. METHODS: Totaly 189 patients (97 males and 92 females, aged 19-65 years) with cracked teeth were selected, randomly divided into two groups and respectively underwent the temporary protection to cracked teeth with the orthodontic band (n=93) and resin temporary crown (n=96) in the comprehensive treatment. Retention effect, periodontal status and patient satisfaction were observed. RESULTS AND CONCLUSION:There were three cases with loose band and one case with faling band in the group of orthodontic band; there were two cases with faling band in the group of resin temporary crown. No significant difference between two groups in the retention effect was found. There were 11 cases of gingivitis or exploring hemorrhage in the group of orthodontic band and 2 cases in the group of resin temporary crown, indicating the periodontal status in the group of resin temporary crown was better than that in the group of orthodontic band (P< 0.05). There were 18 cases of lower satisfaction for poor color, expand feeling caused by the rubber band and discomfort caused by the band protruding from tooth surface in the group of orthodontic band; there were 3 cases of lower satisfaction in the group of resin temporary crown, and the patient satisfaction in the group of resin temporary crown were higher than that in the group of orthodontic band (P < 0.05). There is a better clinical effect in the temporary protection to cracked teeth by using the resin temporary crown, especialy in the terms of retention effect, periodontal status and patient satisfaction.

BACKGROUND:In the deep caries treatment, the pulp capping agent used in indirect pulp can induce the formation of dentin bridge (the complex of dental pulp and dentin), to protect the pulp tissue from stimulus and save the pulp vitality, completely avoid the occurrence of complications, with a higher clinical success rate. OBJECTIVE:To evaluate the differences in clinical efficacy of five kinds of calcium hydroxide preparations. METHODS:Totaly 236 patients with deep caries were selected and randomized to undergo indirect pulp with the double-component calcium hydroxide powder (n=46), Metapex with one-component injection dosage form and the chemical curing calcium hydroxide preparation (n=47), Dycal with the chemical curing calcium hydroxide preparation (n=45), Ionosit-Baseliner (n=49) and Calcimol LC (n=49) with one-component and the light curing calcium hydroxide preparation. The status of the dental pulp, the restoration and the root tip were observed at 1, 6, 12 and 24 months after operation. RESULTS AND CONCLUSION: There was no significant difference between the five groups in the success rate of indirect pulp capping at 1, 6 and 12 months (P> 0.05). At 24 months, the success rate of indirect pulp capping in the double-component calcium hydroxide powder group was lower than that in the other four groups (P < 0.05), but there was no significant difference between the latter four groups (P > 0.05). Metapex, Dycal, Ionosit-Baseliner and Calcimol LC al have a good effect on indirect pulp capping to deep caries, which can be used as agents for long-term pulp protection.

Objective To compare the short-term effects of myocapsular flap repair through minimal posterior approach in Hip arthroplasty with traditional posterior approach in hip arthroplasty in elderly femoral neck fractures. Methods From August 2007 to may 2009, a total of 126 femoral neck fracture patients were randomly divided into two groups, with 63 patients treated with myocapsular flap repair through minimal posterior approach (the modified group), and 63 patients treated with traditional posterior approach (the traditional group). Fifty-eight patients underwent the first-ever total hip replacement and 68 patients underwent artificial double-acting femoral head replacement. Eighty-four cases were inserted with cemented implants and 42 cases with uncemented. Data of incision length, operation time, blood loss volume, drainage amount, blood transfusion volumes were recorded separately. Postoperative complications related to the surgery and hip joint function were also documented. Function of hip joint was scored with Harris scale. All data were statistically analyzed. Results Five patients died within 1 year of surgery, and 4 patients dropped out. All the remained 117 patients were followed up for 12 - 24 months. There were no significant difference in age, type of fracture and artificial the incision length in the modified group was significantly shorter than that in the traditional group([ 10. 5 ± 2. 4 ]cm vs [ 17. 2 ± 3.6 ] cm, t = 3. 012, P = 0. 004). The average operating time was significantly shorter in the modified group compared to the traditional group (t = 2. 455, P = 0. 038). Blood loss, drainage amount, blood transfusion volumes in the modified group were less than those in the traditional group( t = 3.211,2. 986 and 3. 352 ,Ps ＜ 0. 01, respectively). Conclusion Myocapsular flap repair through minimal posterior approach in Hip arthroplasty is a reasonable, mini invasive technique for hip replacement in older with a less blood loss and shorter operating time.fractures

BACKGROUND:Studies have demonstrated that Fe-Cr-Mo soft magnetic aloy has desired magnetic properties and machining properties. Surface Cr6+ plating treatment can significantly enhance the corrosion resistance in oral environment, but its biosecurity needs further testing. OBJECTIVE: To evaluate the biocompatibility of Fe-Cr-Mo soft magnetic aloy with chromium plating. METHODS:Logarithmic growth phase L929 cel suspension was obtained and seeded in 96-wel plates at a cel concentration of 6×107/L. Pure titanium extract, Fe-Cr-Mo soft magnetic aloy original extract, Cr6+-plated Fe-Cr-Mo soft magnetic aloy and PVC extract were added respectively. After 5 days of culture, cel morphology and adherent circumstances were observed. The absorbance value was detected using cel counting kit-8 assay. The relative growth rate of cels in each group was calculated. The cytotoxicity grades of materials were evaluated. RESULTS AND CONCLUSION:In the pure titanium extracts group, the cels with normal morphology showed good adherent growth and no cytotoxicity. In the Fe-Cr-Mo soft magnetic aloy original extract group, the cel morphology and growth status were both good, with occasionaly individual cel lysis. Scattered reddish brown particles were visible in the culture solution, showing no or very mild cytotoxicity. In Cr6+-plated Fe-Cr-Mo soft magnetic aloy extract group, the cels grew wel and showed no or very mild cytotoxicity. In PVC extract group, more than 70% of cels were vacuole-shaped and presented with pyknosis or dissolution, there was a large number of cel debris, and cel growth was inhibited in over 50% cels, showing moderate cytotoxicity or above. The cytotoxicity of Cr6+-plated Fe-Cr-Mo soft magnetic aloy extract was grade 0-1. These results demonstrate that Fe-Cr-Mo soft magnetic aloywith chromium plating has good biocompatibility.

Objective To investigate the effect of preoperative nursing intervention in the prevention of postoperative retention of urine of patients after total knee arthroplasty. Methods 128patients underwent total knee arthroplasty were divided into the intervention group and the control group (64 cases in each group) by random number table.The patients in the control group received routine nursing care and the patients in the intervention group accepted preoperative nursing intervention 3 to 5 days before surgery. The incidence of post-operation urinary retention, catheterization, satisfaction degree and compliance of the patients were compared between the two groups. Results The incidence rate of post-operation urinary retention and catheterization of the patients was respectively 15.6%(10/64) and 7.8%(5/64) in the intervention group,lower than 34.4%(22/64) and 23.4%(15/64) in the control group. The difference was statistically significant (χ2=6.00, 5.93, respectively, P<0.05). The satisfaction degree and compliance of patients were respectively 95.3%(61/64) and 75.0%(48/64) in the intervention group, higher than 85.2%(52/64) and 31.3%(20/64) in the control group,the difference was statistically significant (χ2=6.12, 24.60,respectively, P < 0.05). Conclusions Preoperative nursing intervention have good effect in the prevention of postoperative retention of urine and improving satisfaction degree of patients underwent total knee arthroplasty.

BACKGROUND:Studies have demonstrated that implantation of pile and different amount of residual tooth can change the stress distribution patterns of the tooth dentin within the residual root, and have an effect on the fracture mode of post-core restoration. OBJECTIVE:To evaluate the effects of the different amount of residual tooth on the fracture mode under oblique loading conditions in fiber pile composite resin core ful crown restoration. METHODS:Forty single rooted premolars extracted from orthodontic patients were divided into four groups after root canal preparation and filing. The plane going through buccal and lingual enamel cementum border midpoint and perpendicular to the long axis of the tooth was taken as the reference plane, so that the remaining amount of the tooth were 0, 1, 2, 3 mm. Fiber pile composite resin core metal ful restoration was conducted. After the repair, the oblique loading at 45° and at the rate of 1 mm/min was conducted. Fracture mode and load-displacement curve when root fracture occurred were recorded. RESULTS AND CONCLUSION:The tooth neck fracture usualy occurred in the 0 mm group, and central root fracture usualy occurred in the remaining three groups. There was a significant difference in the total fracture mode between 0 mm group and the remaining three groups (P < 0.05). There was no significant difference in the total fracture mode between 1, 2 and 3 mm groups (P> 0.05). In oblique loading conditions, when the remaining tooth structure was smal, the prosthesis was prone to have dental neck fracture. Fiber posts played a protective role in the tooth root, but the clinical probability of failure increased. The fracture mode was changed with the increase of residual tooth amount, transferring from the neck edge to the root. These results demonstrate that we must retain more tooth tissue from the crown in the restoration of residual root with fiber post-core crown.