Objective The purpose of this study was to evaluate the disinfection effectiveness and properties of acrylic resin via microwave irradiation. Methods Forty acrylic resin base dentures fabricated in a standardized procedure were chosen and divided into Group A,B,C and D randomly. Group A,B and C were immersed in 200ml distilled water and submitted to microwave irradiation at 700W for 3,4,5 minutes individually. Group D was used as positive control. Bacteria specimens from each group were got for culture and numbers were calculated. Then the four groups were tested for the flexural strength and impact strength by universal test machine before and after microwave irradiation sterilization. Results The germicidal ratio of Group B was more than 90% ,while the ratio of group C was 100%. There was no significant difference in flexural strength and impact strength between group C and group D. Conclusions Microwave irradiation for 5 minutes at 700W produced sterilization of dentures contaminated with all bacteria whereas the denture strength is not affected. Microwave irradiation at 700W solution for 5 minutes was effective to sterilize acrylic resin base dentures.

OBJECTIVETo investigate the effect of three different impression methods on the marginal fit of all-ceramic crowns. The three methods include scanning silicone rubber impression, cast models, and direct optical impression.

METHODSThe polymethyl methacrylate (PMMA) material of a mandibular first molar in standard model was prepared with 16 models duplicated. The all-ceramic crowns were prepared using three different impression methods. Accurate impressions were made using silicone rubber, and the cast models were obtained. The PMMA models, silicone rubber impressions, and cast models were scanned, and digital models of three groups were obtained to produce 48 zirconia all-ceramic crowns with computer aided design/computer aided manufacture. The marginal fit of these groups was measured by silicone rubber gap impression. Statistical analysis was performed with SPSS 17.0 software.

RESULTSThe marginal fit of direct optical impression groups, silicone rubber impression groups, cast model groups was (69.18±9.47), (81.04±10.88), (84.42±9.96) µm. A significant difference was observed in the marginal fit of the direct optical impression groups and the other groups (P<0.05). No statistically significant difference was observed in the marginal fit of the silicone rubber impression groups and the cast model groups (P>0.05).

CONCLUSIONAll marginal measurement sites are clinically acceptable by the three different impression scanning methods. The silicone rubber impression scanning method can be used for all-ceramic restorations.

Computer-Aided Design ; Crowns ; Dental Marginal Adaptation ; Dental Porcelain ; Dental Prosthesis Design ; Zirconium

Objective To establish standardized traceable management procedure for implanted high-value consumables in operating room.Methods The management model combining information-based system operation process and quality control process was designed,and management results before and after implementation were compared.Results There were statistically significant differences in error rates of information recording,bar code sticking and charging of implantable high-value consumables after the implementation of the process management mode (P＜0.05).At the same time,there were statistically significant differences in improvement of traceability of high-value consumables,adverse event reporting and patient satisfaction(P＜0.05).Conclusion Establishment of management model in operating room for implanted high-value consumables can ensure medical safety and increase medical quality.It was proved to improve the level of hospital management.

Objective The failure mode and effect analysis (FMEA) were used to monitor the managerial process of high-value consumables in the implantation surgery, and establish the traceable management process for high-value consumables of the implantation surgery. Methods FMEA was used to carry out risk assessment process, formulate specific measures for improvement. The risk priority number(RPN),the qualified rate of the management index of implant surgical consumables,the patients satisfaction, and the number of adverse events reported were compared before and after the implementation of this process management. Results After FMEA was used to conduct management over implant surgery consumables,the RPN value decreased dramatically due to difficulty of traceability, information recording, and imperfect management system, thereby showing that the difference was statistically significant (t=16.655, 10.664, 9.321, P<0.01). Quality management measures: the access to consumables meets the requirements,complete information record,quality of stock consumables,paste bar code standard, charge accurate, return visits and records on time, consumables traceability, patient satisfaction rate were 99.2%(373/376),96.7%(363/376),99.5%(374/376),95.6%(361/376),98.6%(371/376), 95.7% (360/376), 100.0% (376/376), 97.1% (365/376), respectively after the implementation of this process management, which were higher than 90.9% (355/390), 81.8% (319/390), 94.2% (367/390), 91.3% (356/390),84.7%(330/390),87.3%(341/390),87.5%(342/390),91.8%(358/390)before the implementation of this process management, thereby showing that the difference was statistically significant (χ2=7.149-49.371, P<0.01).The number of adverse consumables event reports increased from 0 up to 5. Conclusions It was feasible and effective to improve the level of hospital management and ensure the safety of patients by using the FMEA model in the implantation surgical high-value consumables.

Objective:To sinicize the Index of Dental Anxiety and Fear (IDAF-4C +), and to test its reliability and validity. Methods:According to the Brislin translation model, the literal translation, back translation, cultural adjustment and pre-investigation of the scale were carried out to form the Chinese version of the IDAF-4C + Scale, and the convenience sampling method was used to investigate the outpatients of the Affiliated Stomatological Hospital of Nanchang University from October 2021 to January 2022 to verify the reliability and validity of the scale. Results:The Chinese version of the IDAF-4C + Scale consisted of three modules (core anxiety module, fear module and stress module), with a total of 23 items, of which the core anxiety module included cognitive, physiological, behavioral and emotional dimensions. The content validity index of each item was 0.8-1.0, and the content validity index of the total scale was 0.913; the construct validity was 0.903, and a common factor was extracted by exploratory factor analysis of anxiety module. The contribution rate of cumulative variance was 72.037%. The results of confirmatory factor analysis showed that the model fitted well and all the adaptation indexes were up to the standard. Using the Modified Dental Anxiety Scale (MDAS) as the criterion, the correlation coefficient between IDAF-4C module and MDAS was 0.66, the Cronbach α coefficient of the scale was 0.913, and the test-retest reliability was 0.923. Conclusions:The Chinese version of the IDAF-4C + Scale has good reliability and validity and can be used as a tool to measure and evaluate the level of dental anxiety and fear in oral patients.