Objective: To measure the color of dental CAD/CAM alumina-glass-composites(AGC). Methods: Dental CAD/CAM alumina block were infiltrated at 1 120 ℃ by laboratory made AG1,AG2,AG3 and AG4 color serials of infiltration glass powder and Vita In-Ceram Alumina AL1,AL2,AL3 and AL4 infiltration glass respectively. Specimens were made with the area of 10 mm?10 mm,thickness of 0.5,1 and 1.5 mm respectively. Color parameters were measured by Minolta CM-2600d spectrophotometer. Results:The specimen with the thickness of 1 mm was used as the standard for color measurement.After infiltration with AL1-AL4 glass powder,the color parameters of Vita alumina core ceramic were L*: 69.39-78.41,a*:1.82- 4.02,b*:18.35-24.42,when infiltrated with AG1-AG4 glass powder, the color parameters of CAD/CAM AGC were L*:68.80-78.44,a*:1.32- 4.75,b*:16.85- 21.86. b*value and chroma of the AG3 core ceramic were lower than that of AL3 core ceramic,while a* value was higher.b* value and chroma of the AG1 and AG2 core ceramic were lower than that of AL1 and AL2 core ceramic. The reflectance curve of CAD/CAM AGC infiltrated by AG1-AG4 glass powder demonstrated the similar trend as that of the core ceramic infiltrated by Vita In-Ceram glass powder. Conclusion: The color range and surface reflection rate of laboratory made AG1-AG4 AGC are similar with those of Vita AL1-AL4 In-Ceram Alumina core and may meet the need of color match with veneer ceramics.

objective: To investigate the effects of cerium oxide content on the color of alumina glass composite. Methods: Infiltration glass powder with different content of cerium oxide (1%～4%) were fabricated. Alumina glass composite was prepared by infiltrating molten glass into presintered alumina block at 1 250 ℃ for 2 h, and the color of the alumina glass composite were measured with Minolta chromatic instrument(CR 321) . For comparison, the color of VITA In Ceram alumina technical shade guide was recorded too. Results: After infiltration, the b * range of the alumina glass composite was in accord with that of the shade guide. With the increasing content of the cerium oxide, a *, b * and chroma increased, L * decreased, the hue of the alumina glass composite shifted from yellow green to yellow red. Conclusion: Cerium oxide may effectively enhance b * of the alumina glass composite, but its ability of reducing L * and enhancing a * is weak.

Objective; To study the chromatic distribution of the chromatic value of Vitapan 3D- Master shade guide in color space. Methods: The color space of.Vitapan 3D-Master shade guide was measured and analyzed with CIE-1976-L* a* b. system and MINOLTA chromatic instrument (CR-321 ) under D65 standard source. Results: 26 shades of Vitapan 3D-Master could be divided into 5 groups according to the 3-dimensional layers. Inside the 2nd, 3th and 4th group, 6 shades distributed as equidistant ring circling M2 shade because their hue and chroma were different. The hue of L1. 5 and L2. 5 deflected to yellow, R1.5 and R2. 5 to red,that of M1-3 was intervenient. Conclusion: Vitapan 3D-Master shade guide is equidistant in color space and can be used more effeciently than Vitapan classical. Its chromatic value distribution perfectly and evenly covered color region of nature tooth.

OBJECTIVETo develop an HPLC-DAD-ELSD method for detecting the fingerprint of Astragali Radix and evaluate the quality through similarity calculation and chemical pattern recognition.

METHODSeparation was performed at 25 degreeC on an Agilent Zorbax ODS C18 column(4.6 mm x250 mm,5 microm). Gradient elution was performed with the mobile phases of acetonitrile and water containing 0. 2% formic acid. The flow rate was 0. 8 mL min-1 , and sample size was 10 microL. The UV detection wavelength was set at 280 nm. The drift tube temperature for ELSD was set at 110 degreeC , and the nebulizing gas flow rate was 3.0 L min-1. The similarity calculation and chemical pattern recognition were used for fingerprint analysis.

RESULTThe HPLC-DAD-ELSD method for chromatographic fingerprint of Astragali Radix showed better results of stability, precision and repeatability. The reference chromatographic fingerprint of Astragali Radix was established on the eighteen Astragali Radix samples from different sources. The results of similarity calculation were higher than 0. 83, which was in accordance with the result of chemical pattern recognition analysis.

CONCLUSIONFingerprint and chemical pattern recognition analysis could effectively distinguish Astragali Radix from different source, which could be applied to the quality control of Astragali Radix.

OBJECTIVETo find an inhibitor to reduce the volatilization of formalin.

METHODThe saturated solution of sodium hydrosulphite (SHS) was sprayed on the surface of the anatomy specimens, then the concentration of formaldehyde in the air was tested.

RESULTSThe concentration of formaldehyde in the air of SHS sprayed group [(3.10 +/- 1.22) mg/m3] was significantly lower than that of the control group [(8.36 +/- 4.11) mg/m3, P < 0.01].

CONCLUSIONSHS may be a volatilization inhibitor for formalin, which could reduce the concentration of formaldehyde in the air.

Objective: To evaluate the efficacy of a self-developed mobile augmented reality navigation system (MARNS) in guiding spinal level positioning during intraspinal tumor surgery based on a dual-error theory. Methods: This retrospective study enrolled patients diagnosed with intraspinal tumors admitted to Fujian Provincial Hospital between May and November 2023. The participants were divided into conventional x-rays and self-developed MARNS groups according to the localization methods they received. Position time, length of intraoperative incision variation, and location accuracy were systematically compared. Results: A total of 41 patients (19 males) with intraspinal tumors were included, and MARNS was applied to 21 patients. MARNS achieved successful lesion localization in all patients with an error of 0.38±0.12 cm. Compared to x-rays, MARNS significantly reduced positioning time (129.00±13.03 seconds vs. 365.00±60.43 seconds, p<0.001) and length of intraoperative incision variation (0.14 cm vs. 0.67 cm, p=0.009). Conclusion The self-developed MARNS, based on augmented reality technology for lesion visualization and perpendicular projection, offers a radiation-free complement to conventional x-rays.

Objective: To evaluate the efficacy of a self-developed mobile augmented reality navigation system (MARNS) in guiding spinal level positioning during intraspinal tumor surgery based on a dual-error theory. Methods: This retrospective study enrolled patients diagnosed with intraspinal tumors admitted to Fujian Provincial Hospital between May and November 2023. The participants were divided into conventional x-rays and self-developed MARNS groups according to the localization methods they received. Position time, length of intraoperative incision variation, and location accuracy were systematically compared. Results: A total of 41 patients (19 males) with intraspinal tumors were included, and MARNS was applied to 21 patients. MARNS achieved successful lesion localization in all patients with an error of 0.38±0.12 cm. Compared to x-rays, MARNS significantly reduced positioning time (129.00±13.03 seconds vs. 365.00±60.43 seconds, p<0.001) and length of intraoperative incision variation (0.14 cm vs. 0.67 cm, p=0.009). Conclusion The self-developed MARNS, based on augmented reality technology for lesion visualization and perpendicular projection, offers a radiation-free complement to conventional x-rays.

Objective: To evaluate the efficacy of a self-developed mobile augmented reality navigation system (MARNS) in guiding spinal level positioning during intraspinal tumor surgery based on a dual-error theory. Methods: This retrospective study enrolled patients diagnosed with intraspinal tumors admitted to Fujian Provincial Hospital between May and November 2023. The participants were divided into conventional x-rays and self-developed MARNS groups according to the localization methods they received. Position time, length of intraoperative incision variation, and location accuracy were systematically compared. Results: A total of 41 patients (19 males) with intraspinal tumors were included, and MARNS was applied to 21 patients. MARNS achieved successful lesion localization in all patients with an error of 0.38±0.12 cm. Compared to x-rays, MARNS significantly reduced positioning time (129.00±13.03 seconds vs. 365.00±60.43 seconds, p<0.001) and length of intraoperative incision variation (0.14 cm vs. 0.67 cm, p=0.009). Conclusion The self-developed MARNS, based on augmented reality technology for lesion visualization and perpendicular projection, offers a radiation-free complement to conventional x-rays.

Objective: To evaluate the efficacy of a self-developed mobile augmented reality navigation system (MARNS) in guiding spinal level positioning during intraspinal tumor surgery based on a dual-error theory. Methods: This retrospective study enrolled patients diagnosed with intraspinal tumors admitted to Fujian Provincial Hospital between May and November 2023. The participants were divided into conventional x-rays and self-developed MARNS groups according to the localization methods they received. Position time, length of intraoperative incision variation, and location accuracy were systematically compared. Results: A total of 41 patients (19 males) with intraspinal tumors were included, and MARNS was applied to 21 patients. MARNS achieved successful lesion localization in all patients with an error of 0.38±0.12 cm. Compared to x-rays, MARNS significantly reduced positioning time (129.00±13.03 seconds vs. 365.00±60.43 seconds, p<0.001) and length of intraoperative incision variation (0.14 cm vs. 0.67 cm, p=0.009). Conclusion The self-developed MARNS, based on augmented reality technology for lesion visualization and perpendicular projection, offers a radiation-free complement to conventional x-rays.

Objective: To evaluate the efficacy of a self-developed mobile augmented reality navigation system (MARNS) in guiding spinal level positioning during intraspinal tumor surgery based on a dual-error theory. Methods: This retrospective study enrolled patients diagnosed with intraspinal tumors admitted to Fujian Provincial Hospital between May and November 2023. The participants were divided into conventional x-rays and self-developed MARNS groups according to the localization methods they received. Position time, length of intraoperative incision variation, and location accuracy were systematically compared. Results: A total of 41 patients (19 males) with intraspinal tumors were included, and MARNS was applied to 21 patients. MARNS achieved successful lesion localization in all patients with an error of 0.38±0.12 cm. Compared to x-rays, MARNS significantly reduced positioning time (129.00±13.03 seconds vs. 365.00±60.43 seconds, p<0.001) and length of intraoperative incision variation (0.14 cm vs. 0.67 cm, p=0.009). Conclusion The self-developed MARNS, based on augmented reality technology for lesion visualization and perpendicular projection, offers a radiation-free complement to conventional x-rays.