1.The oral mucosa irritation test for colored alumina-glass composite
Ning WEN ; Hongchen LIU ; Longquan SHAO
Medical Journal of Chinese People's Liberation Army 1983;0(02):-
Objective To study the biosafety of colored alumina-glass composite by mucosa irritation test. Methods The colored alumina-glass composite and a non-irritating material were separately fixed to the oral mucosa of a mouse. The contact parts were examined with bare eye, histologically and cytologically. Results No obvious inflammation of the mucosa was detected in the site where colored alumina-glass composite was in contact. Conclusion Alumina-glass composite has good biosafety.
2.The effect of ozone aging on the physical properties of SY-1silicon elastomer
Yan CUI ; Yimin ZHAO ; Longquan SHAO
Journal of Practical Stomatology 2001;0(03):-
0.05) respectively. Conclusion: The SY 1 silicon elastomer have suitable physical, mechanical and anti ozone aging properties.
3.Galvanic corrosion of soft magnetic alloy and 4 types of dental alloys in common use
Jingguang PAN ; Yimin ZHAO ; Longquan SHAO
Journal of Practical Stomatology 1996;0(02):-
Objective: To study the property of galvanic corrosion of soft magnetic alloy and 4 kinds of dental alloys in simulated oral environment. Methods: 6 samples of Ni Cr, TA 2, Ti75 and 30 of Fe 16Cr 2Mo in the size of d 15 mm?3 mm were prepared and put into artificial saliva. An electrochemical method was used in the measurement of electric potential of corrosion (Ecorr), potential dynamic polarization and galvanic current density of different galvanic couple, the anticorrosive property of four galvanic couples was analyzed statistically. Results: The ecorr value(mV) of Ti75, TA 2, Co Cr,Fe 16Cr 2Mo and Ni Cr was -138.31?2.89, -150.35?1.04, -186.21?3.79, -218.35?0.84 and -240.49?1.73 respectively ( P
4.Assessment of mechanical properties of three silicone elastomers
Fang SU ; Yimin ZHAO ; Longquan SHAO
Journal of Practical Stomatology 2001;0(03):-
0.05);the elongation (%) 470?9.5,560?8.2 and 470?5.8 (SY-1 versus SY-2 or MDX-4-4210,P
5.Study on infinity optical thickness of SY-1 silicone elastomers
Lixian ZHANG ; Yimin ZHAO ; Longquan SHAO
Journal of Practical Stomatology 2001;0(03):-
Objective: To find out the infinity optical thickness of SY-1 silicone elastomers when color difference(△E) is equal to 1.5 . Methods: Silicone elastomer samples with thickness from 0.5 mm to 10 mm of SY-1 silicone elastomer were measured by CIE-1976-L *a *b * relative to CIE source against a white and a black background by using Minolta colorimeter . Color difference was calculated as △E=[(△L *) 2+( △a *) 2+(△b *) 2] 1/2 . The infinity optical thickness of SY-1 silicone elastomer when △E=1.5 was calculated by regression formulation. Result: When △E was equal to 1.5, the infinity optical thickness of SY-1 silicone elastomer was 7.60 mm. Conclusion: In order to get ideal effect the supports should be treated with colorant when the thickness of silicone elastomer covering the surface of supports in maxillofacial prostheses is thinner than 7.60 mm.
6.Tensile property and hardness of SY-1 and MDX4-4210 silicon rubber
Longquan SHAO ; Yimin ZHAO ; Xinyi ZHAO
Journal of Practical Stomatology 1996;0(02):-
0.05).The elongation at break of SY-1 was stronger than that of MDX4-4210 (P
7.Adherence of Candida albicans on the surface of silicone elastomer
Longquan SHAO ; Yimin ZHAO ; Jucai YANG
Journal of Practical Stomatology 2000;0(06):-
砄bjective:To compare the adherent ability of Candida albicans on the surface of two kinds of silicone elastomer used as prosthodontic materials and to study the factors affecting the adherence.Methods: Candida albicans were cultured on the surface of SY 1 and MDXA 4210 with or without saliva acquired pellicle for 10 min, then the number of the bacteria was counted.Results:With or without saliva acquired pellicle,the number (1?10 3/mm 2) of C.albicans on SY 1 was 24.5?0.88 and 2.0?0.47 respectively( P 0.05 ).Conclusion:There is little difference between the adherent ability of C.albicans on the two kind of silicone elastomer.Saliva acquired pellicle can decrease the adherence.
8.Effects of ozone aging on the color stability of SY-1 silicone elastomer
Yan CUI ; Yiming ZHAO ; Longquan SHAO
Journal of Practical Stomatology 1995;0(04):-
Objective:To study the effects of ozone aging on the color stability of the SY-1 silicone elastomer. Methods :40 SY-1 silicone elastomer samples were prepared and grouped into 4 with 10 in each group. The samples in each group were painted with gouache color, oil pigment and inorganic salt respectively, one group was used as the control. Then the samples were treated with ?=10 -4 % ozone at 10~16 mm/s for 72 h. The color of the samples were measured by 1976 CIE L *a *b * standards of chromatic aberration before and after ozone treatment. The chromatic aberration was expressed as △E=〔△L *)2+(△a *)2+(△b *)2〕 1/2. Results :After 72 hours of ozone aging, △E of the samples in the groups of control, gouache color, oil pigment and inorganic salt was 0.55?0.11, 3.55 ? 0.09, 1.40 ? 0.11 and 1.57 ? 0.07 respectively ;Conclusion:Under the ozone aging condition, the SY-1 silicone elastomers stained with oil pigment and inorganic salt may have better color stability than that with gouache color.
9.Adhesive properties between GP-084 cellular silicone elastomer and SY-1 silicone elastomer
Ying HAN ; Yimin ZHAO ; Longquan SHAO
Journal of Practical Stomatology 2000;0(05):-
0.05).Tight integration was found between the two materials in the two groups and there was no distinct interface examined by SEM.Conclusions:GP-084 cellular silicone elastomer and SY-1 silicone elastomer may be adhered completly.
10.Research of stomatology teaching for international medical students
Longquan SHAO ; Ting SUN ; Daohong LIU ; Rui TAN
Chinese Journal of Medical Education Research 2011;10(7):858-860
A questionnaire survey was conducted among undergraduate international students to investigate the effects of stomatology teaching.The effects of stomatology teaching had been proved to be fair, while some shortcomings had also emerged. In further teaching adjustments have to be made to teaching plans and teachers' Enghsh abilities are expected to be improved.