Objective; To evaluate the reliability and reasonability of maxillofacial skin color match using the digital camera. Methods; The stability of the experimental light source was evaluated before establishing the color measurement. 122 volunteers aged from 22 to 32 years were recorded by a Canon EOS 20D digital camera in studio environment when the light source was stable. Photographs were taken under a set exposure parameters(f/4.5,1/25 s,custom white balance,ISO 800) and saved as JPEG format. The CIE L~* a~* b~* color values were obtained from the digital images using Adobe Photoshop7.0 after color correction. All data were analyzed using SPSS 10. 0. Results;The experimental light source was stable in 21 to 70 minutes. It was suitable for color measurement during this period. The color parameters of all tested maxillofacial skin were:L~*49～66,a~*7 - 18,b~*5 -22. Conclusion;The assessment of maxillofacial skin color depend on method of measurement and instrument. The method of maxillofacial skin color matching by digital camera seems reliable.

Objective: To evaluate the effect of roughness on adhesive properties of polymethyl methacrylate and SY-1 silicone elastomer.Methods:5 specimens of polymethyl methacrylate were polished by sand paper of different standards and the roughness of polymethyl methacrylate surfaces were measured by roughmeter. The tension strength between polymethyl methacrylate with different degrees of roughness and SY-1 silicone elastomer were tested according to national standards. Results: After the surfaces of polymethyl methacrylate were respectively polished by sand paper of the standard 160,320 and 800, the sufrace roughness decreased, but the tension strength between polymethy1 and SY-1 silicone elastomer was increased(P

0.05).The elongation at break of SY-1 was stronger than that of MDX4-4210 (P

Objective:Through monitoring the pH of the growth medium,to evaluate the growth and/or acid production ability of Candida albicans on silicon elastomer incorporated with two different antifungal agents.Methods:Antifungal agents(AntimTM-AM and Conval pag-40)were added at concentrations from 0% to 2%,and antibacterial effect of the material in saliva and serum groups were examined.The third group added nothing was served as the control.Results:Each group with 2% antifungal agents showed great inhibitory effects on the acid production and /or the growth of C.albicans.These inhibitory effects consisted of a delay in the onset of rapid pH decline,decreased with the rate of pH change and increased in minimum pH.As a result,Conval pag-40 showed a significantly greater antimicrobial effect than AntimTM-AM.Conclusion:Silicone elastomer material incorporated with antifungal agents have strong antibacterial ability and can satisfy the requirements of clinical application.

Objective:To evaluate a new wax formed by laser sintering technology(SW-1)for dental use.Methods:The melting point,hardness and viscosity of SW-1,normal dental modeling wax and LongYuan's wax formed by laser sintering were tested and compared.Linear shrinkage,plastic deformation and toughness of SW-1 were estimated by national standards.Results:There were no significant differences between SW-1and the normal dental modeling wax in the properties of melting point 〔(61.1?1.63)℃,(61.7?1.96)℃〕and hardness 〔(75.2?0.62)HA,(74.0?0.54)HA〕;but when compared with melting point(78.3?1.07)℃and hardness(94.0?0.38)HA of LongYuan's wax formed by laser Sintering,those of SW-1 were significantly different.Viscosity of SW-1(2 016?136.9)MPa?s showed significant difference when compared with that of normal dental modeling wax(9.06?0.258)MPa?s and LongYuan's wax formed by laser Sintering(2 876?81.7)MPa?s.Linear shrinkage of SW-1(0.2%)met the national standards,while plastic deformation(10%,43 ℃)and toughness(broken when bent,20 ℃)of SW-1 did not meet such standards.Conclusion:SW-1 may be the proper laser sintering material for dental use,and has a good prospect in future.

Objective:To evaluate the effects of primers on the bonding of an silicone elastomer to acrylic resin.Methods:Acrylic resin specimens were divided into eight groups.Six new primers and Cosmesil G611 primer were applied to the acrylic resin surfaces respectively.Untreated group was used as control.The shear bond strengths between silicone elastomer and acrylic resin were determined.D primer were measured by Forier transform infrared spectroscopy,and the bands were analyzed using spectrum method.Results:The experiment group with different concentration of ?-MPS showed different shear bond strengths between silicone elastomer and acrylic resin.Type D primer showed 2.20 MPa shear bond strength,which was significantly higher than that of other groups.While 1.44 MPa for Cosmesil G611 primer was found,there was no bond strength for untreated group.Conclusion:The concentration of ?-MPS is relative to the shear bond strength and type D primer can give the highest shear bond strength.

Objective To summarize the progresses made domestically and abroad and the developmental tendency of stomatology,and to propose the orientation of development in stomatology in China. Methods The latest progresses and developmental tendency in the field of stomatology were achieved by investigating related references,reviews,research reports and treatises published in recent 10 years. Results In recent years,the increasing integration of stomatology,comprehensive medicine,biomedical engineering,and tissue engineering facilitated the development of stomatology towards digitization,minimal invasion,functionalization and customization,which has made great achievements in basic researches and clinical techniques of stomatology in the armed forces. Conclusions It is the key period of the Twelfth Five-Year Plan for the development of the stomatology in the armed forces. Servicing the basic level of the troop,promoting dominant subjects,improving weak components of the discipline,and comprehensively promoting the internationalization should be insisted in driving innovations of stomatology in the armed forces.

Objective: To explore the possibility to restore alveolar process cleft and the defects of front maxillae with telescope techniques. Methods: 4-5 telescopes were used as retainers of a prosthesis for cleft alveloar process or the defects of front maxillae; metal framework was used as connector of abutments and obturator in soft-tissue defect. Porcelain or resinmetal crowns were applied to restore defects in dentition. Acrylic resin was applied to repairs the deftcts of alveolar process and front maxillae or defect of palate. By above ways, prostheses were fabricated, the patients were followed up. Results:The following up for 26-28 months in 6 cases showed that the prosthesis retained with telescopes had follow advantages: good retention, convenient application, high masticatary function and satisfactory esthetics effects. Conclusion:The prosthesis with telescopes is feasible for the restoration of cleft alveolar process and the defects of front maxillae.

0.05) respectively. Conclusion: The SY 1 silicon elastomer have suitable physical, mechanical and anti ozone aging properties.

Objective: To study the anatomic structure of the nasopalatine duct and the neighboring bone,provide reference for implant surgery in the incisor region. Methods: Manual quantitative measurement of the nasopalatine duct were performed in 73 maxilla specimens (38 from male and 35 from female). Results: The angle between the anterior wall of nasopalatine duct and the nasal floor was 114.80??11.00?, the angle between the cortical plate of anterior maxilla and the nasal floor 107.28??10.75?, the length of the nasopalatine duct was (15.63?2.18) mm in male, and ( 14.59 ?1.96) mm in female, the width of nasal opening of the duct was ( 4.92 ?1.46) mm in male, and (5.73?1.50) mm in female, the width of oral opening of the duct was (3.23?0.60) mm in male and (3.83?0.92) mm in female, at the level of nasal floor, the distance between the anterior wall of the duct and cortical plate of anterior maxilla was (6.15?1.90) mm. Conclusion: In front of nasopalatine duct, implants should be implanted parallel to nasopalatine duct,with an angle about 115? between the implant direction and nasal floor. The bone in front of nasopalatine duct was thin,the diameter of implants applied here should be less than 4 mm.