[Evaluation of the fabrication deviation of a kind of milling digital implant surgical guides].

OBJECTIVE: To evaluate the deviation of digital implant surgical guides during fabrication process in the Organical Dental Implant (ODI) system. METHODS: This study included two parts. The first part was the in vitro study. A resin block with a diagnostic template was used for the planning. After cone beam computed tomography (CBCT) scanning, a surgical guide with eight implants was virtually designed using the ODI system. The guide was milled by a 5-axial numerical controlled milling machine, and an optical scanning was taken to digitalize the guide to a standard tessellation language (STL) form. The STL data were then imported into an ODI software and registered with the original design. The deviation of the sleeves between the design and the STL was measured in the ODI software and set as the golden standard. Then the ODI examination table was used to measure the deviation of the guide during fabrication. Examiners A and B measured 10 times separately. The reliability and the validity of the examination table was calculated. The second part was the in vivo study: The deviation during fabrication of 12 guides designed and fabricated by the ODI system were measured using the examination table. RESULTS: The standard deviation of the deviation measured using the examination table by examiners A and B were all below 0.40 mm (for the shell reference points) and 0.71 degree (for the angles). No significant difference was found between the two examiners for any implant sites. The result of the examination table was larger than that of the software for the shell reference point (t-test, P<0.05), but no significant difference was found for the angle deviation (t-test, P>0.05). The 45 implants positions in the 12 guides for the in vivo study were examined using the examination table. The deviations at the shell reference points were (1.06±0.29) mm (0.42-1.75 mm), and at the implant tip were (1.12±0.48) mm (0.41-2.44 mm). The angle deviations were (1.42±0.70) degree (0.29-2.96 degree). CONCLUSION: Deviation is unavoidable during the fabrication process of the guides. The examination table of the ODI system is a reliable and valid tool to measure the deviation during fabrication of the ODI guides. More studies should be designed to research the relationship between the fabrication deviation and the implant insertion deviation.

Cryoprotectant-free ultra-rapid freezing of human spermatozoa in cryogenic vials.

The objective of this study was to investigate the effect of ultra-rapid freezing (direct immersion in liquid nitrogen) on human spermatozoa in cryogenic vials (≥0.5 ml) at different concentrations of sucrose. After swim-up, the sperm suspensions (N = 58) were diluted with sperm preparation medium and divided into six aliquots: swim-up (fresh), conventional freezing group (slow freezing) and four ultra-rapid freezing groups containing sucrose at different concentrations (0.15 m, 0.20 m, 0.25 m and 0.30 m). Sperm motility, progressive motility, plasma membrane integrity, DNA stability and acrosome integrity of fresh and cooled-warmed spermatozoa were analysed. The progressive motility, plasma membrane and acrosome integrity of spermatozoa in the 0.20 m sucrose group were significantly higher than those of the slow freezing group (47.5 ± 6.8% versus 36.4 ± 8.7%, 73.2 ± 6.9% versus 63.9 ± 6.3%, 53.7 ± 10.0% versus 35.9 ± 9.7% respectively, P < 0.05). However, no differences were found in sperm motility or DNA stability (58.5 ± 6.3% versus 54.2 ± 5.3%, 90.1 ± 2.8% versus 87.2 ± 4.7%, P > 0.05 respectively) between the 0.20 m sucrose and the slow freezing group. No differences were found between the ultra-rapid and slow freezing group at the other concentrations of sucrose. Our findings suggest that the method of ultra-rapid freezing of human spermatozoa in cryogenic vials with a solution containing 0.20 m sucrose results in recovery of spermatozoon of superior qualities. In contrast to slow freezing, the ultra-rapid freezing technique of human spermatozoa seems to reduce cryoinjuries and maintain important physiological characteristics of the spermatozoa after warming.

Value of microsurgical varicocelectomy for severe oligo-asthenospermia patients failed in fertilization assisted by in vitro fertilization.

OBJECTIVE: To investigate the clinical effect of microsurgical varicocelectomy on severe oligo-asthenospermia patients failing in fertilization assisted by intracytoplasmic sperm injection. PATIENTS AND METHODS: From January 2013 to August 2014, forty-nine patients with severe oligo-asthenospermia and serious varicoceles were treated by microsurgical varicocelectomy after failing in fertilization assisted by intracytoplasmic sperm injection (ICSI), eleven of whom had varicoceles on the left side and thirty-eight had bilateral varicoceles. Patients were followed up for the natural pregnancy condition, changes of routine semen parameters and reproductive hormone level and the embryonic development and outcome of next IVF-ET (ICSI) cycles within 6 months. RESULTS: After surgery, 61.2% (30/49) of spouses obtained clinical pregnancy. Among whom 22.4% (11/49) were naturally pregnant, 32.65% (16/49) were conceived after second IVF-ET assistance, and 6.1% (3/49) were conceived with the third or further assistance of ICSI-ET. The overall miscarriage rate was 16.7% (5/30). All of the patients had improvement in the sperm concentration and forward motility. The sperm concentration increased from (10.53 ± 8.76) × 106/ml to (20.23 ± 11.76) × 106/ml. The ratio of forward motile sperm was increased to (30.52 ± 18.78) % from (8.75.52 ± 6.36) % (p < 0.01). The serum total testosterone (T) improved from (2.19 ± 1.03) ng/ml to (4.05 ± 0.64) ng/ml (p < 0.05). Serum follicle-stimulating hormone (FSH) changed from (5.23 ± 1.26) mIU/ml to (3.76 ± 2.22) mIU/ml after the procedure. Luteinizing hormone (LH) changed from (4.38 ± 1.36) to (3.98 ± 1.38) mIU/ml. Estrogen (E2) changed from 40.28 ± 7.26 pg/ml to 35.24 ± 5.75 pg/ml. Prolactin (PRL) level elevated from (18.24 ± 4.28) to (17.16 ± 2.16) ng/ml (p > 0.05). The fertility rate of in vitro fertilization significantly improved to (83.36 ± 19.36) % from (72.36 ± 17.88) % (p < 0.05). The rate of 2PN ratio increased from (66.73 ± 17.93) % to (75.96 ± 20.39) %. The cleavage rate increased from (83.26 ± 32.33) % to (90.35 ± 23.66). The abnormal fertility rate were (5.36 ± 12.58) % and (7.26 ± 13.89) % before and after the procedure (p > 0.05), while the rate of high-quality embryos increased significantly from (34.36 ± 33.27) % to (55.67 ± 23.36) % (p < 0.05). The rate of transferable embryos remained without significant change (70.67 ± 30.6% before and 60.53 ± 30.27% after the procedure). The anabiosis rate of frozen embryo increased from (66.32 ± 30.69) % to (89.72 ± 29.69) %. The further blastocyst rate improved from (10.98 ± 9.7) % to (30.27 ± 15.33) % (p < 0.01). CONCLUSIONS: The microsurgical varicocelectomy effectively improved sperm parameters, the fertility rate of oocyte fertilized in vitro and the anabiosis rate and blastocyst rate of the frozen embryo for on patients with severe oligo-asthenospermic, and further increased the odds of natural pregnancy, the rate of high-quality embryos and the success rate of in vitro fertilization.