Objective To investigate the morphology and biomechanics of in vivo osteogensis after repairing rabbit skull defects with plastic engineered bone which was prefabricated with alginate gel, osteoblasts and bone granules. Methods Twenty-eight rabbits were divided into group A (n=16), group B(n=8) and group C(n=4).The bilateral skull defects of 1 cm in diameter were made. Left skull defects filled with alginate gel-osteoblasts-bone granules(group A1) and right skull defects filled withalginate gel-bone granules(group A2).The defects of group B was left, as blank control and group C had no defect as normal control. The morphological change and bone formation were observed by methods of gross, histology and biomechanics. Results In group A1, the skull defects were almost entirely repaired by hard tissue 12 weeks after operation. The alginate gel-osteoblasts-bone granule material had changed into bone tissue with fewbone granules and some residuary alginate gel. The percentage of bone formation area was 40.92%±19.36%. The maximum compression loading on repairing tissue ofdefects was 37.33±2.95 N/mm; the maximum strain was 1.05±0.20 mm; andloading/strain ratio was 35.82±6.48 N/mm. In group A2, the alginate and bone granules material partially changed into bone tissue 12 weeks after operation. The percentage of bone formation area was 18.51%±6.01%. The maximum compression loading was 30.59±4.65 N; the maximum strain was 1.35±0.44 mm; and the loading/strainratio was 24.95±12.40 N/mm. In group B, the skull defects were mainly repaired bymembrane-like soft tissue with only few bone in marginal area；the percentage of bone formation area was 12.72%±9.46%. The maximum compression loading was 29.5±2.05 N; the maximum strain was 1.57±0.31mm；and the loading/strainratio was 19.90±5.47 N/mm.In group C, the maximum compression loading was 41.55±2.52 N; the maximum strain was 095±017 mm; and the l oading/strain ratio was 47.57±11.22 N/mm. 〖 WTHZ〗Conclusion〓〖WTBZ〗The plastic engineered bone prefabricated with algina te gelosteoblastsbone granule may shape according to the bone defects and ha s good ability to form bone tissue, whose maximum compression loading can reach 89 % of normal skull and the hardness at 12 weeks after operation is similar to that of normal skull.
Objective To summarize the current progress of laser-assisted cartilage reshaping (LACR) for prominent ear. Methods The domestic and abroad article concerning the LACR in treatment of prominent ear was reviewed and analyzed. Results As a new technique, there were three types of LACR therapies that been used for prominent ear. LACR with the 1 064 nm Nd/YAG laser is painful and the penetration depth of the 1 064 nm Nd/YAG laser is greater than that of the 1540 nm Er/Glass laser which is caused more tissue injury. LACR with the 1 540 nm Er/Glass laser has high absorption by the ear cartilage and produce less injury to the surrounding tissue. Use of the CO2 laser permitted cartilage reshaping combined with both vaporization and incisions, which complicates the technique, although, with low recurrence rate and definite effect. Insisting on wearing ear mold is the key to get satisfactory effectiveness for postoperative patients. The complications of LACR for prominent ear, such as the dermatitis, perforation of the skin, hematoma, or infection, should be noticed. Conclusion Application of LACR for prominent ear just has a short period of time, limited number of cases, and few relevant literature reports. Its effectiveness needs to be further studied and clarified.
ObjectiveTo establish a method to prefabricate titanium plate with three-dimensional (3-D) printing technique for correction of mandibular prognathism in sagittal splint ramous osteotomy (SSRO). MethodsBetween January 2012 and May 2013, 12 patients with mandibular prognathism (Angle III malocclusion) were treated. Among them, 9 cases were male and 3 cases were female. Their ages ranged from 19 to 35 years (mean, 25.6 years). With the 3-D facial CT data of these patients, 3-D printer was used to print the models for preoperational simulation. SSRO was performed on 3-D models, and the titanium plates were prefabricated on the models after the distal segments were moved backward and rotated according to occlusal splint. During operations, the proximal segments were fixed to distal segments by the prefabricated titanium plates. 3-D CT scans were taken to examine the temporomandibular joint position changes before operation and at 6 months after operation. ResultsThe skull models were manufactured by 3-D printing technique, and the titanium plates were reshaped on the basis of them. Twenty-four prefabricated titanium plates were placed during operations, and they all matched with the bone segments well. Evaluation of 3-D CT scans showed that the temporomandibular joint position had no change. All patients were followed up 7-12 months (mean, 10.6 months). The face type and dental articulation were improved greatly. All cases obtained satisfactory opening function and occlusion. ConclusionWith the titanium plate fabricated based on 3-D models, surgeons are able to improve or refine surgical planning so that the operation can be performed according to preoperative simulation precisely and the complications, such as dislocation of temporomandibular joint, can be prevented.
ObjectiveTo explore the effectiveness and advantage of three-dimensional (3D) printing technology in treatment of internal or external ankle distal avulsed fracture.MethodsBetween January 2015 and January 2017, 20 patients with distal avulsed fracture of internal or external ankle were treated with the 3D guidance of shape-blocking steel plate fixation (group A), and 18 patients were treated with traditional plaster external fixation (group B). There was no significant difference in gender, age, injury cause, disease duration, fracture side, and fracture type between 2 groups (P>0.05). Recording the fracture healing rate, fracture healing time, the time of starting to ankle functional exercise, residual ankle pain, and evaluating ankle function recovery of both groups by the American Orthopaedic Foot and Ankle Society (AOFAS) score.ResultsAll patients were followed up 8-24 months, with an average of 15.5 months. In group A: all incisions healed by first intention, the time of starting to ankle functional exercise was (14±3) days, fracture healing rate was 100%, and the fracture healing time was (10.15±2.00) weeks. At 6 months, the AOFAS score was 90.35±4.65. Among them, 13 patients were excellent and 7 patients were good. All patients had no post-operative incision infection, residual ankle pain, or dysfunction during the follow-up. In group B: the time of starting to ankle functional exercise was (40±10) days, the fracture healing rate was 94.44%, and the fracture healing time was (13.83±7.49) weeks. At 6 months, the AOFAS score was 79.28±34.28. Among them, 15 patients were good, 2 patients were medium, and 1 patient was poor. During the follow-up, 3 patients (16.67%) had pain of ankle joint with different degrees. There were significant differences in the postoperative fracture healing rate, fracture healing time, the time of starting to ankle functional exercise, and postoperative AOFAS score between 2 groups (P<0.05).ConclusionApplication of 3D printing technology in treatment of internal or external ankle distal avulsed fracture is simple, safe, reliable, and effective. In particular, it is an ideal treatment for avulsed fracture.
ObjectiveTo evaluate the correlation between the Mohawk (MKX) expression level and the collagen fiber diameter of autologous hamstring tendon graft during the stable graft remodeling phase after anterior cruciate ligament (ACL) reconstruction.MethodsBetween January 2018 and August 2018, patients who underwent arth-roscopic single-bundle anatomical ACL reconstruction with autologous hamstring tendons for at least 48 months and also underwent second-look arthroscopy were enrolled in study. During the second-look arthroscopic procedures, ACL graft biopsies were performed from the surface of central part of the ligament. MKX expressions of ACL grafts were analysed by real-time fluorescent quantitative PCR (qRT-PCR). The ultrastructure of collagen fibers of grafts were evaluated by transmission electron microscopy, which included average diameter of collagen fibers (Dc), average diameter of large-diameter collagen fibers (DL), average diameter of small-diameter collagen fibers (DS), and large-small collagen fibers ratio (RL/S). The correlation between MKX expression level and graft collagen fiber diameter was calculated.ResultsTwenty-six patients met the selection criteria and their ACL graft specimens were enrolled in the study. The interval between ACL reconstruction and second-look arthroscopy was 52-128 months, with an average of 78.6 months. Arthroscopic graft remodeling score was 3-6 (mean, 4.8). There were 17 cases of excellent remodeling and 9 cases of fair remodeling. All ACL grafts showed typical bimodal distributions of both large-diameter collagen fibers and small-diameter collagen fibers, but the ultrastructural characteristics of the graft collagen fibers were different according to different remodeling status under arthroscopy. The DC, DL, DS, and RL/S of the graft specimens were (65.2±9.3) nm, (91.6±10.5) nm, (45.7±8.6) nm, and 0.73±0.12, respectively. The relative expression level of MKX was 1.42±0.11, which was positively linearly correlated with DC, DL, and RL/S, and the correlation coefficient was statistically significant (r=0.809, P=0.000; r=0.861, P=0.000; r=0.942, P=0.000), while there was no significant correlation between DS and relative expression level of MKX (r=0.147, P=0.238). Regression analysis showed that the relative expression level of MKX could predict the DC, DL, and RL/S results of the ACL graft specimens (P<0.05).ConclusionAfter autologous hamstring tendon grafts stepped into stabilized remodeling phase, MKX expression level could predict the diameter measurement results of collagen fibers and be used as an important evaluation basis for graft collagen anabolic metabolism.
ObjectiveTo investigate the effect of “noncycloplegic retinoscopy for screening myopia + subsequent wearing orthokeratology lens” process for primary and secondary school students based on physical examination center.MethodsA total of 172 primary and secondary school students undergoing vision examination in the Health Management Department (i.e. physical examination center) of the Second Affiliated Hospital of Xi’an Jiaotong University between January 2017 and December 2018 were selected as the research objects. After examination by noncycloplegic retinoscopy in the health management department, they were examined by mydriatic retinoscopy in the ophthalmology department, and then the consistency of the results of the two methods was analyzed. Then 93 students with myopia diagnosed by both methods were randomly divided into control group (n=46) and trial group (n=47), wearing frame glasses and orthokeratology lenses respectively. The diopter, eye axial length, corneal curvature and vitreous cavity depth before wearing glasses, as well as the increment of the above indicators at 3, 6 and 12 months after wearing glasses/lenses were compared between the two groups, and the incidence of complications of the two groups were compared.ResultsCompared with mydriatic retinoscopy, the positive predictive value of noncycloplegic retinoscopy was 88.6%, the sensitivity was 96.9% and the specificity was 84.2%, and the consistency kappa coefficient was 0.821 (P<0.001). Before wearing glasses/lenses, there was no significant difference in diopter, eye axial length, corneal curvature or vitreous cavity depth of both eyes between the two groups (P>0.05); at 3, 6 and 12 months after wearing glasses/lenses, the diopter increment and eye axial increment of both eyes of the trial group were less than those of the control group [left eye diopter increment: (0.48±0.07) vs. (0.73±0.08) D, (0.69±0.13) vs. (1.04±0.11) D, (0.88±0.11) vs. (1.13±0.11) D; left eye axial increment: (0.18±0.05) vs. (0.26±0.04)mm, (0.22±0.04) vs. (0.36±0.04) mm, (0.27±0.05) vs. (0.40±0.05) mm; right eye diopter increment: (0.46±0.10) vs. (0.73±0.09) D, (0.71±0.12) vs. (1.04±0.10) D, (0.90±0.10) vs. (1.17±0.11) D; right eye axial increment: (0.17±0.04) vs. (0.24±0.04) mm, (0.23±0.04) vs. (0.37±0.04) mm, (0.26±0.05) vs. (0.42±0.05) mm] (P<0.05). At 3, 6 and 12 months after wearing glasses/lenses, the changing trends of corneal curvature and vitreous cavity depth in both eyes of the trial group were different from those of the control group (PInteraction<0.05), and the corneal curvature of both eyes at each time point was lower than that before wearing lenses and that of the control group (P<0.05), while the vitreous cavity depth of both eyes was not statistically different from that before wearing lenses (P>0.05) but lower than that of the control group (P<0.05). There was no statistical difference in the incidence of common complications between the two groups (P>0.05).ConclusionIn the physical examination center, the accuracy of noncycloplegic retinoscopy for general survey of myopia in primary and secondary school students is high, and then after the diagnosis by mydriatic retinoscopy in the special department, the use of orthokeratology lens can effectively control the progress of myopia, so the process of “noncycloplegic retinoscopy for screening myopia in physical examination center + subsequent wearing orthokeratology lens in specialty” is feasible.
Objective To prepare a new plastic bone filler material with adhesive carrier and matrix particles derived from human bone, and evaluate its safety and osteoinductive ability through animal tests. MethodsThe human long bones donated voluntarily were prepared into decalcified bone matrix (DBM) by crushing, cleaning, and demineralization, and then the DBM was prepared into bone matrix gelatin (BMG) by warm bath method, and the BMG and DBM were mixed to prepare the experimental group’s plastic bone filler material; DBM was used as control group. Fifteen healthy male thymus-free nude mice aged 6-9 weeks were used to prepare intermuscular space between gluteus medius and gluteus maximus muscles, and all of them were implanted with experimental group materials. The animals were sacrificed at 1, 4, and 6 weeks after operation, and the ectopic osteogenic effect was evaluated by HE staining. Eight 9-month-old Japanese large-ear rabbits were selected to prepare 6-mm-diameter defects at the condyles of both hind legs, and the left and right sides were filled with the materials of the experimental group and the control group respectively. The animals were sacrificed at 12 and 26 weeks after operation, and the effect of bone defect repair were evaluated by Micro-CT and HE staining. Results In ectopic osteogenesis experiment, HE staining showed that a large number of chondrocytes could be observed at 1 week after operation, and obvious newly formed cartilage tissue could be observed at 4 and 6 weeks after operation. For the rabbit condyle bone filling experiment, HE staining showed that at 12 weeks after operation, part of the materials were absorbed, and new cartilage could be observed in both experimental and control groups; at 26 weeks after operation, the most of the materials were absorbed, and large amount of new bone could be observed in the 2 groups, while new bone unit structure could be observed in the experimental group. Micro-CT observation showed that the bone formation rate and area of the experimental group were better than those of the control group. The measurement of bone morphometric parameters showed that the parameters at 26 weeks after operation in both groups were significantly higher than those at 12 weeks after operation (P<0.05). At 12 weeks after operation, the bone mineral density and bone volume fraction in the experimental group were significantly higher than those in the control group (P<0.05), and there was no significant difference between the two groups in trabecular thickness (P>0.05). At 26 weeks after operation, the bone mineral density of the experimental group was significantly higher than that of the control group (P<0.05). There was no significant difference in bone volume fraction and trabecular thickness between the two groups (P>0.05). Conclusion The new plastic bone filler material is an excellent bone filler material with good biosafety and osteoinductive activity.
ObjectiveTo summarize the difficulties and key points of free deep inferior epigastric artery perforator flap (DIEP) transplantation in breast shaping of two-staged breast reconstruction with vertical scar.MethodsThe clinical data of 32 postoperative breast cancer patients after mastectomy who underwent free DIEP transplantation for breast reconstruction between October 2015 and October 2019, whose original surgical incisions were all vertical and longitudinal, were retrospectively analysed. All the patients were female, aged from 31 to 42 years, with an average of 34.6 years. The disease duration of breast cancer ranged from 9 to 48 months (mean, 22.8 months). Free DIEP pedicled with contralateral vessels were used in all cases, and the recipient vessels were intrathoracic vessels. Among them, 17 flaps were placed longitudinally, 15 flaps were placed obliquely; Z-shaped flaps were used in 18 cases to adjust the chest wall skin contracture, and contralateral breast reduction and mastopexy were accomplished at the same time in 23 cases.ResultsAll DIEP survived completely, and all donor and recipient sites healed by first intention. Internal thoracic lymph node metastasis was found in 1 case and treated with radiotherapy. All 32 cases were followed up 9-48 months, with an average of 19.4 months. The appearance and texture of all flaps were satisfactory, and only linear scar was left in donor site. Eleven patients underwent further autologous fat transplantation and nipple reconstruction. All patients had no effect on abdominal wall activity, and no local recurrence and metastasis was found.ConclusionIt is difficult to use free DIEP for two-staged breast reconstruction in patients received mastectomy with vertical longitudinal scar left. Combined with different breast shaping techniques, the outcomes can significantly improve.