The effect of various sandblasting conditions on surface changes of dental zirconia and shear bond strength between zirconia core and indirect composite resin

Jiefei Shen,Xin Li,Naichuan Su,Wenjia Liu,Yunmao Liao,Li Yue,Hang Wang,Hai Zhang 대한치과보철학회 2015 The Journal of Advanced Prosthodontics Vol.7 No.3

PURPOSE To measure the surface loss of dental restorative zirconia and the short-term bond strength between an indirect composite resin (ICR) and zirconia ceramic after various sandblasting processes. MATERIALS AND METHODS Three hundred zirconia bars were randomly divided into 25 groups according to the type of sandblasting performed with pressures of 0.1, 0.2, 0.4 and 0.6 MPa, sandblasting times of 7, 14 and 21 seconds, and alumina powder sizes of 50 and 110 µm. The control group did not receive sandblasting. The volume loss and height loss on zirconia surface after sandblasting and the shear bond strength (SBS) between the sandblasted zirconia and ICR after 24-h immersion were measured for each group using multivariate analysis of variance (ANOVA) and Least Significance Difference (LSD) test (α=.05). After sandblasting, the failure modes of the ICR/zirconia surfaces were observed using scanning electron microscopy. RESULTS The volume loss and height loss were increased with higher sandblasting pressure and longer sandblasting treatment, but they decreased with larger powder size. SBS was significantly increased by increasing the sandblasting time from 7 seconds to 14 seconds and from 14 seconds to 21 seconds, as well as increasing the size of alumina powder from 50 µm to 110 µm. SBS was significantly increased from 0.1 MPa to 0.2 MPa according to the size of alumina powder. However, the SBSs were not significantly different with the sandblasting pressure of 0.2, 0.4 and 0.6 MPa. The possibilities of the combination of both adhesive failure and cohesive failure within the ICR were higher with the increases in bonding strength. CONCLUSION Based on the findings of this study, sandblasting with alumina particles at 0.2 MPa, 21 seconds and the powder size of 110 µm is recommended for dental applications to improve the bonding between zirconia core and ICR.

The influence of suture materials on the biomechanical behavior of suture-meniscal specimens: a comparative study in a porcine model

( John Reza Matthews ),( Jiefei Wang ),( Jiwei Zhao ),( Melissa A. Kluczynski ),( Leslie J. Bisson ) 대한슬관절학회 2020 대한슬관절학회지 Vol.32 No.-

Background: Repair of a meniscal tear is indicated in certain conditions. Despite extensive research on the biomechanics of various repair methods, there has been minimal investigation of whether the suture material influences the meniscal-suture construct. The purpose of this study was to compare the biomechanical properties of nine different suture materials under cyclic and load-to-failure conditions. Methods: Ninety porcine menisci were randomly allocated to simple suture placement using either Ultrabraid^®, Ultratape^{^®}, Magnum Wire^®, TigerWire^®, TigerTape^®, LabralTape^®, Orthocord^®, 0 FiberWire^®, or 2-0 FiberWire^®. Each suture-meniscus specimen underwent cyclic loading followed by load-to-failure testing. Elongation, maximum load to failure, stiffness, and mode of failure were recorded and compared between each suture type using nonparametric testing. Mean ± standard deviation was reported and the statistical significance was p < 0.05. Results: Elongation during cyclic loading was lowest with 2-0 FiberWire (0.95 ± 0.17 mm); this value was statistically significantly different than the results for all other sutures except 0 FiberWire^® (1.09 ± 0.17 mm, p = 0.79), TigerWire^® (1.09 ± 0.29 mm, p = 0.85), TigerTape^® (1.39 ± 0.29 mm, p = 0.08), and LabralTape^® (1.20 ± 0.33 mm, p = 0.41). The highest elongation was seen with Ultrabraid^® (1.91 ± 0.34 mm); this value was statistically significantly greater than the results for all other suture materials except Orthocord^® (1.59mm± 0.31 mm, p = 0.46) and Magnum Wire^® (1.43 ± 0.25 mm, p = 0.14). Load to failure was highest for TigerTape^® (287.43 ± 41.15 N), and this result was statistically significantly different than the results for all other sutures except LabralTape^® (271.34 ± 48.48 N, p = 0.99) and TigerWire^® (251.03 ± 25.8 N, p = 0.51). Stiffness was highest for LabralTape^® (195.77 ± 49.06 N/mm), and this result was statistically significantly different than the results for all other sutures except TigerWire^® (186.49 ± 19.83 N/ mm, p = 0.45) and TigerTape^® (173.35 ± 15.60 N/mm, p = 0.19). The majority of sutures failed by pullout (n = 46, 51%) or tearing (n = 40, 45%). Conclusion: Suture design and material affect the biomechanical behavior of porcine meniscal-suture specimens. LabralTape^®, TigerWire^®, and TigerTape^® demonstrated better overall combinations of low elongation, high maximum load to failure, and high stiffness.

Three-dimensional analysis of the outcome of different scanning strategies in virtual interocclusal registration

Jiansong Mei,Liya Ma,Jiarui Chao,Fei Liu,Jiefei Shen 대한치과보철학회 2022 The Journal of Advanced Prosthodontics Vol.14 No.6

PURPOSE. The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS. Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies. Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS. For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION. Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations

A comparative study to measure the sagittal condylar inclination using mechanical articulator, virtual articulator and jaw tracking device

Liya Ma,Fei Liu,Jiansong Mei,Jiarui Chao,Zhenyu Wang,Jiefei Shen 대한치과보철학회 2023 The Journal of Advanced Prosthodontics Vol.15 No.1

Purpose. To compare the sagittal condylar inclination (SCI) in dentate individuals measured by the different methods with mechanical articulator (MA), virtual articulator (VA), and a jaw tracking device (JTD) system. Materials and methods. A total of 22 healthy dentate participants were enrolled in this study. For MA workflow, the SCI was obtained by a semi-adjustable articulator with protrusive interocclusal records. The SCI was also set on a VA by aligning intraoral scan (IOS) with cone beam computed tomography (CBCT) and facial scan (FS), respectively. These virtual workflows were conducted in a dental design software, namely VAIOS-CBCT and VAIOS-FS. Meanwhile, a JTD system was also utilized to perform the measurement. Intraclass correlation was used to assess the repeatability within workflows. The bilateral SCI values were compared by Wilcoxon matched-pairs signed rank test for each workflow, and Kruskal-Wallis test and post hoc p-value Bonferroni correction were used to compare the differences among four workflows. The agreement of VAIOS-CBCT, VAIOS-FS, and JTD compared with MA was evaluated by Bland-Altman analysis. Results. Intraclass correlation of the SCI revealed a high degree of repeatability for each workflow. There were no significant differences between the left and right sides (P > .05), except for VAIOS-CBCT (P = .028). Significant differences were not found between MA and VAIOS-FS (P > .05). Bland-Altman plots indicated VAIOS-CBCT, VAIOS-FS, and JTD were considered to substitute MA with high 95% limits of agreement. Conclusion. The workflow of VAIOS-FS provided an alternative approach to measure the SCI compared with MA.

Corticosterone Regulates the Expression of Neuropeptide Y and Reelin in MLO-Y4 Cells

Yuanyuan Ma,Hang Wang,Xiangnan Wu,Jing Fu,Jiefei Shen,Xiaoyu Li 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.6

Osteocytes that have a dendritic appearance are widely believed to form a complex cellular network system and play crucial roles in mechanotransduction as a principal bone mechanosensor, which is the basis of their neuronal-like biology, as previously reported. Neuropeptide Y (NPY) and reelin mRNA, which are brain-specific neurogenic markers, have been identified in osteocytes. However, changes in the production of NPY and reelin in response to specific biochemical stimulation are unknown. In this study, we investigated the in vitro effect of corticosterone, one of the endogenous glucocorticoids, on the expression of NPY and reelin in the MLO-Y4 osteocyte cell line. Cells were treated with corticosterone at different concentrations (10-9 M-10-5 M) for 1, 3, 6, 12 and 24 h. As revealed, corticosterone reduced the MLO-Y4 cell viability and pro-liferation in a dose- and time-dependent manner based on an MTT assay and a Vi-CELL analyzer. The cells were then incubated with corticosterone (10-6 M), and the NPY and reelin expression levels were detected at 1, 3, 6, 12 and 24 h using real-time PCR and Western blot analysis. These results demonstrated that at the gene and the protein levels, corticosterone significantly upregulated the NPY and reelin expression in a time-dependent manner. The application of a glucocorticoid receptor antagonist, RU486, reversed the reduced cell viability and the increased expression of NPY and reelin that were caused by corticosterone. To the best of our knowledge, this is the first report to verify that corticosterone regulates the NPY and reelin expression in osteocytes.

Erratum - The effect of various sandblasting conditions on surface changes of dental zirconia and shear bond strength between zirconia core and indirect composite resin

Naichuan Su,Li Yue,Yunmao Liao,Wenjia Liu,Hai Zhang,Xin Li,Hang Wang,Jiefei Shen 대한치과보철학회 2015 The Journal of Advanced Prosthodontics Vol.7 No.6

The effect of various sandblasting conditions on surface changes of dental zirconia and shear bond strength between zirconia core and indirect composite resin

Su, Naichuan,Yue, Li,Liao, Yunmao,Liu, Wenjia,Zhang, Hai,Li, Xin,Wang, Hang,Shen, Jiefei The Korean Academy of Prosthodonitics 2015 The Journal of Advanced Prosthodontics Vol.7 No.3

PURPOSE. To measure the surface loss of dental restorative zirconia and the short-term bond strength between an indirect composite resin (ICR) and zirconia ceramic after various sandblasting processes. MATERIALS AND METHODS. Three hundred zirconia bars were randomly divided into 25 groups according to the type of sandblasting performed with pressures of 0.1, 0.2, 0.4 and 0.6 MPa, sandblasting times of 7, 14 and 21 seconds, and alumina powder sizes of 50 and $110{\mu}m$. The control group did not receive sandblasting. The volume loss and height loss on zirconia surface after sandblasting and the shear bond strength (SBS) between the sandblasted zirconia and ICR after 24-h immersion were measured for each group using multivariate analysis of variance (ANOVA) and Least Significance Difference (LSD) test (${\alpha}$=.05). After sandblasting, the failure modes of the ICR/zirconia surfaces were observed using scanning electron microscopy. RESULTS. The volume loss and height loss were increased with higher sandblasting pressure and longer sandblasting treatment, but they decreased with larger powder size. SBS was significantly increased by increasing the sandblasting time from 7 seconds to 14 seconds and from 14 seconds to 21 seconds, as well as increasing the size of alumina powder from $50{\mu}m$ to $110{\mu}m$. SBS was significantly increased from 0.1 MPa to 0.2 MPa according to the size of alumina powder. However, the SBSs were not significantly different with the sandblasting pressure of 0.2, 0.4 and 0.6 MPa. The possibilities of the combination of both adhesive failure and cohesive failure within the ICR were higher with the increases in bonding strength. CONCLUSION. Based on the findings of this study, sandblasting with alumina particles at 0.2 MPa, 21 seconds and the powder size of $110{\mu}m$ is recommended for dental applications to improve the bonding between zirconia core and ICR.