1.Effect of internal structures on the accuracy of 3D printed full-arch dentition preparation models in different printing systems
Teng MA ; Tiwu PENG ; Yang LIN ; Mindi ZHANG ; Guanghui REN
The Journal of Advanced Prosthodontics 2023;15(3):145-154
PURPOSE:
. The objective of this study was to investigate how internal structures influence the overall and marginal accuracy of full arch preparations fabricated through additive manufacturing in different printing systems.
MATERIALS AND METHODS:
. A full-arch preparation digital model was set up with three internal designs, including solid, hollow, and grid. These were printed using three different resin printers with nine models in each group. After scanning, each data was imported into the 3D data processing software together with the master cast, aligned and trimmed, and then put into the 3D data analysis software again to compare the overall and marginal deviation whose results are expressed using root mean square values and color maps. To evaluate the trueness of the resin model, the test data and reference data were compared, and the precision was evaluated by comparing the test data sets. Color maps were observed for qualitative analysis. Data were statistically analyzed by one-way analysis of variance and Bonferroni method was used for post hoc comparison (α = .05).
RESULTS:
. The influence of different internal structures on the accuracy of 3D printed resin models varied significantly (P < .05). Solid and grid models showed better accuracy, while the hollow model exhibited poor accuracy. The color maps show that the resin models have a tendency to shrink inwards.
CONCLUSION
. The internal structure design influences the accuracy of the 3D printing model, and the effect varies in different printing systems. Irrespective of the kind of printing system, the printing accuracy of hollow model was observed to be worse than those of solid and grid models. [J Adv Prosthodont 2023;15:145-54]
2.Comparison of three-dimensional position of maxillary dentition model treated with two digital transfer methods
Tiwu PENG ; Teng MA ; Zhikang YANG ; Mindi ZHANG ; Guanghui REN
Chinese Journal of Stomatology 2024;59(1):80-84
Objective:To compare and evaluate the difference in maxillary dentition position using an anatomical facebow and jaw movement analyzer.Methods:From March to May 2023, 15 medical interns from Yantai Stomatological Hospital were recruited, including 9 males and 6 females, aged 20-25 years. Digital models and plaster models of maxillary dentition were obtained from the 15 medical interns. The anatomical facebow group (AFB) and jaw movement analyzer group (JMA) were used to transfer the position of the maxillary dentition to the virtual articulator. The virtual occlusal articulator module of exocad denture design software was used to measure the inclination angle of the occlusal plane of the two groups, the distance between the mesio-incisal angle of the left maxillary central incisor and the lateral center point of the lateral condylar sphere of the virtual occlusal articulator, the distance between the mesial buccal cusp of the maxillary first molar and the lateral center point of the lateral condyle sphere of the virtual articulator. The same marks (mesial incisor point of left maxillary central incisor and mesial buccal cusp point of both maxillary first molars) were measured in two groups of maxillary dentition, and the root-mean-square error between 3 points was calculated.Results:The occlusal plane inclination angle in AFB group (9.11°±3.85°) was significantly larger than that in JMA group (4.94°±2.69°) ( t=10.45, P<0.001). There were significant differences between AFB and JMA groups. The distances from the mesial cusp of the left first molar to the lateral center of the left condylar, from the mesial cusp of the left maxillary central incisor to the lateral center of the left condylar[(91.75±3.05), (129.09±4.60) mm]were significantly smaller than those in the JMA group[(95.68±5.45), (132.41±5.64) mm]( t=-4.48, P=0.001; t=-4.21, P=0.001). In both groups of models, the distance of the mesial cusp of the left maxillary central incisor was (8.81±2.56) mm, and the distance between mesial buccal cusp of maxillary left first molar was (7.56±2.49) mm, the distance between mesial buccal cusp of maxillary right first molar was (7.13±2.77) mm; the root mean square error was (7.93± 2.94) mm. Compared with 0, the difference was statistically significant ( t=10.45, P<0.001). Conclusions:There were differences between the two methods (anatomical facebow and the jaw movement analyzer) for transferring the maxillary dentition position to the three-dimensional space position of the virtual articulator.
3.Efficacy and safety of LY01005 versus goserelin implant in Chinese patients with prostate cancer: A multicenter, randomized, open-label, phase III, non-inferiority trial.
Chengyuan GU ; Zengjun WANG ; Tianxin LIN ; Zhiyu LIU ; Weiqing HAN ; Xuhui ZHANG ; Chao LIANG ; Hao LIU ; Yang YU ; Zhenzhou XU ; Shuang LIU ; Jingen WANG ; Linghua JIA ; Xin YAO ; Wenfeng LIAO ; Cheng FU ; Zhaohui TAN ; Guohua HE ; Guoxi ZHU ; Rui FAN ; Wenzeng YANG ; Xin CHEN ; Zhizhong LIU ; Liqiang ZHONG ; Benkang SHI ; Degang DING ; Shubo CHEN ; Junli WEI ; Xudong YAO ; Ming CHEN ; Zhanpeng LU ; Qun XIE ; Zhiquan HU ; Yinhuai WANG ; Hongqian GUO ; Tiwu FAN ; Zhaozhao LIANG ; Peng CHEN ; Wei WANG ; Tao XU ; Chunsheng LI ; Jinchun XING ; Hong LIAO ; Dalin HE ; Zhibin WU ; Jiandi YU ; Zhongwen FENG ; Mengxiang YANG ; Qifeng DOU ; Quan ZENG ; Yuanwei LI ; Xin GOU ; Guangchen ZHOU ; Xiaofeng WANG ; Rujian ZHU ; Zhonghua ZHANG ; Bo ZHANG ; Wanlong TAN ; Xueling QU ; Hongliang SUN ; Tianyi GAN ; Dingwei YE
Chinese Medical Journal 2023;136(10):1207-1215
BACKGROUND:
LY01005 (Goserelin acetate sustained-release microsphere injection) is a modified gonadotropin-releasing hormone (GnRH) agonist injected monthly. This phase III trial study aimed to evaluated the efficacy and safety of LY01005 in Chinese patients with prostate cancer.
METHODS:
We conducted a randomized controlled, open-label, non-inferiority trial across 49 sites in China. This study included 290 patients with prostate cancer who received either LY01005 or goserelin implants every 28 days for three injections. The primary efficacy endpoints were the percentage of patients with testosterone suppression ≤50 ng/dL at day 29 and the cumulative probability of testosterone ≤50 ng/dL from day 29 to 85. Non-inferiority was prespecified at a margin of -10%. Secondary endpoints included significant castration (≤20 ng/dL), testosterone surge within 72 h following repeated dosing, and changes in luteinizing hormone, follicle-stimulating hormone, and prostate specific antigen levels.
RESULTS:
On day 29, in the LY01005 and goserelin implant groups, testosterone concentrations fell below medical-castration levels in 99.3% (142/143) and 100% (140/140) of patients, respectively, with a difference of -0.7% (95% confidence interval [CI], -3.9% to 2.0%) between the two groups. The cumulative probabilities of maintaining castration from days 29 to 85 were 99.3% and 97.8%, respectively, with a between-group difference of 1.5% (95% CI, -1.3% to 4.4%). Both results met the criterion for non-inferiority. Secondary endpoints were similar between groups. Both treatments were well-tolerated. LY01005 was associated with fewer injection-site reactions than the goserelin implant (0% vs . 1.4% [2/145]).
CONCLUSION:
LY01005 is as effective as goserelin implants in reducing testosterone to castration levels, with a similar safety profile.
TRIAL REGISTRATION
ClinicalTrials.gov, NCT04563936.
Humans
;
Male
;
Antineoplastic Agents, Hormonal/therapeutic use*
;
East Asian People
;
Gonadotropin-Releasing Hormone/agonists*
;
Goserelin/therapeutic use*
;
Prostate-Specific Antigen
;
Prostatic Neoplasms/drug therapy*
;
Testosterone