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BACKGROUND: Local application of bone marrow mesenchymal stem cells has the ability to promote bone tissue regeneration and repair; however, whether it could play a significant role via vein injection and its ability of bone tissue regeneration and repair at different ages still need to be clarified. OBJECTIVE: To explore the effects of bone marrow mesenchymal stem cells on the repair ability of skull injury in young and aging mice via vein injection. METHODS: Totally 40 1-month-old Kunming mice were obtained as young mice, and 40 12-month-old Kunming mice were obtained as aging mice. The mice were divided into young experimental group, young control group, aging experimental group, and aging control group. The bone defect was made in the cranium of the mice. At 1, 8, and 15 days after surgery, 0.2 mL bone marrow mesenchymal stem cell suspension (1×1010 L-1) was injected into the tail vein of mice in the experimental groups; meanwhile, an equal volume of saline was used in the control groups via tail vein. The mice were sacrificed at 1 and 3 weeks after surgery. The specimens were repaired for the following experiments: morphological, histopathological, optical, and immunohistochemical analyses. RESULTS AND CONCLUSION: (1) Micro-CT imaging: At 1 week after surgery, there was no significant difference in the size of bone defect area between the young and aging groups, and the size of the bone defect area was reduced significantly in the experimental groups at 3 weeks after surgery. (2) Hematoxylineosin staining and Masson staining: The collagen fibers appeared at 1 week after surgery; meanwhile, the bone matrix emerged at 3 weeks after surgery in the defect area. The collagen fibers and the bone matrix were significantly more in the experimental groups than those in the control groups. (3) Non-linear light microscopy: At 3 weeks after the operation, the comparison of collagen content in the defect area was as follows: young experimental group > young control group; aging experimental group > aging control group. (4) Immunohistochemical analysis: At 1 and 3 weeks after operation, Sirt1 protein expression was more in the young groups than that in the aging groups. At 1 week, the Sirt1 protein expression was more in the experimental groups than that in the control groups. At 3 weeks, the Sirt1 protein expression was less in the aging experimental group than that in the aging control group. (5) It is concluded that bone marrow mesenchymal stem cells promoted the repair of skull defects in the mice of different ages significantly via the tail vein injection, which mainly promotes bone regeneration by activating Sirt1 expression in mice. [ABSTRACT FROM AUTHOR]

BACKGROUND: Polyetheretherketone and titanium mesh are commonly used in skull repair, but there is no clinical trial evidence of long-term (such as 2 years after operation) repair effect and safety comparison between the two materials. OBJECTIVE: To evaluate the long-term effect and adverse events of polyetheretherketone and titanium mesh in repairing skull defects. METHODS: This is a prospective, single-center, non-randomized controlled, 2-year follow-up clinical trial. Sixty inpatients scheduled for skull repair in the Fourth Affiliated Hospital of China Medical University will be enrolled and divided into two groups according to different intraoperative skull repair materials. Polyetheretherketone and titanium mesh materials will be used in the trial and control groups, respectively (n=30 per group). All patients will be followed up for 6, 12, and 24 months. This trial was approved by the Medical Ethics Committee of the Fourth Affiliated Hospital of China Medical University on February 1, 2021 (approval No. EC-2021-HS-002). This trial meets the requirements of the Declaration of Helsinki formulated by the World Medical Association. All patients are required to sign an informed consent form. The recruitment time will be from August 1, 2021 to August 1, 2022. Result analysis time will be from September 1, 2024 to September 30, 2024. Completion time will be October 31, 2024. RESULTS AND CONCLUSION: Primary outcome measure is rate of failure in skull repair at 24 months after surgery. Secondary outcome measures are rate of failure in skull repair at 6 and 12 months after surgery; the incidence of adverse events to assess safety of implant materials; Glasgow Outcome Scale scores to evaluate the recovery of neurological function; satisfaction score for body shaping to assess skull shaping effect; and head CT imaging to assess skull injury healing at 6, 12, and 24 months after surgery. Cost-effectiveness ratio and incremental cost-effectiveness ratio will be used to assess the difference in cost effectiveness of the two materials at 6, 12, and 24 months after surgery. The trial hopes to prove that compared with titanium mesh, the use of polyetheretherketone for skull repair has a better repair effect for 2 years, a lower incidence of adverse events, better biocompatibility, and obvious advantages in long-term efficacy and security. This study was registered with the Chinese Clinical Trial Registry on February 27, 2021 (registration number: ChiCTR2100043703). Study protocol version is 1.0. [ABSTRACT FROM AUTHOR]

Objective To investigate the application of neuroendoscopy and curative effect of lateral skull base surgery via transcranial approach. Methods Clinical data of 142 cases undergoing endoscopic lateral skull base surgeries via transcranial approach from July 2015 to July 2018 were retrospectively analyzed. There were 32 cases of primary hemifacial spasm, 56 cases of primary trigeminal neuralgia, 2 cases of primary glossopharyngeal neuralgia, 15 cases of epidermoid cyst, 14 cases of acoustic neuroma, 3 cases of trigeminal schwannoma, 18 cases of pontocerebellar trigone meningioma, and 2 cases of jugular foramen schwannoma. Among them, 90 cases (32 cases of primary hemifacial spasm, 56 cases of primary trigeminal neuralgia and 2 cases of primary glossopharyngeal neuralgia) underwent endoscopic microvascular decompression (MVD) via transcranial approach, and 52 cases (15 cases of epidermoid cyst, 14 cases of acoustic neuroma, 3 cases of trigeminal schwannoma, 18 cases of pontocerebellar trigone meningioma, and 2 cases of jugular foramen schwannoma) underwent endoscopic removal of lateral skull base tumors via transcranial approach. Results All the operations were performed under endoscopy, including 96 cases (67.61%) operated by single hand (the endoscope was held by a pneumatic arm) and the rest 46 cases (32.39%) operated by both hands. The cure rate of MVD was 87.78% (79/90) and the total removal rate of lateral skull base tumors was 90.38% (47/52). The mean follow - up period was (23.46 ± 8.93) months. There was no death or other serious complications. Conclusions The complex lateral skull base surgery via transcranial approach can be performed by neuroendoscope with pneumatic endoscopic fixed arm. It has the advantages of near and multi - angle observation, clear visual field, full exposure and high recognition of nerve and blood vessels. However, the requirements for endoscopic technology, instruments and assistive equipments are high, and it is necessary to receive relevant trainings and experiences in endoscopic surgery. [ABSTRACT FROM AUTHOR]

Objective To observe the clinical effect of personalized 3D printed titanium mesh in the repair of cranial bone defects. Methods Thirty patients with cranial bone defects in the hospital from January 2015 to December 2018 were selected. The personalized titanium mesh was designed according to the shape and size of bone defects by using 3D printing technology for conducting the the repair of cranial bone defects. The postoperative skull appearance improvement, repair effect and complications occurrence were observed. Results The postoperative appearance of 30 cases was satisfactory, and the skull could be basically restored to its original shape without the occurrence of intracranial infection and hemorrhage. One case appear ed the titanium mesh exposure in postoperative 3 months, which was repaired by scalp any flap transfer. Conclusion The application of personalized 3D printed titanium mesh for repairing the cranial bone defect has a satisfactory postoperative effect and can be promoted and used in clinic. [ABSTRACT FROM AUTHOR]

Objective: To study the effect of BAM bone grafting combined with inactivated autologous porous bone flap in repairing skull defect in rats., Methods: Seventy-two Wistar rats with skull defect were randomly divided into control group, inactivated autologous bone flap group (AB group), BAM bone-induced artificial bone material group (BAM group), and inactivated autologous bone flap with BAM bone-induced artificial bone group (BAM+AB group). The bone healing was evaluated with micro-CT and the new bone formation was assessed with histological staining at 1, 2, and 3 months after modeling., Results: Inactivated porous bone flap combined with BAM bone-induced artificial bone effectively induced vascular and fibrous tissue regeneration and osteogenesis in the cranial defects. With the inactivated porous bone flap as the scaffold, BAM bone-induced artificial bone obviously promoted the restoration of the skull appearance in the rats with cranial defects., Conclusion: Inactivated autologous bone flap group and BAM bone-induced artificial bone material can promote skull healing and restoration of the original skull appearance, and can be used for reconstruction of the local anatomy of the skull surface.

In the researches of biomechanics for child craniocerebral injury, the research progress of performance parameter detection for brain, skull, cranial suture and dura mater, and the finite element model construction for child's head were reviewed. Meanwhile, the shortcomings of the established finite element model construction of child's head were analyzed. Thus, it is necessary to strengthen the material properties parameter detection of child's head, and establish the relevant database, so as to lay the foundation for establishing an accurate finite element model of child's head., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objective: To evaluate influence of assemble flavone of rhizome drynaria (AFDR) on the value of the blood serum alkalinity phosphatase (ALP), calcium (Ca), phosphorus (P), creatinine (Cr) and glutamic-pyruvic transaminase (GPT) in rats model with skull defects., Methods: Sixty SD male rats with age of 6-month were feeded for a week and then were randomly divided into control group and AFDR group, with 30 rats in each group. Left and right skull of rats were perforated with electromotive drill and the model of skull defects was made. Injectable bone regeneration vomposite (IBRC) was implanted right skull defects. The rats of control group and AFDR group were respectively lavaged with AFDR and deionized water at the first day after operation. The rats were respectively killed at the 2nd,4th and 8th week and the blood serum ALP, Ca, P, Cr, GPT were detected and analyzed by statistics., Results: At the 2nd week after operation, blood serum ALP in AFDR group was higher than that of control group. At the 4th week after operation, blood serum Ca, P, and calcium-phosphorus product in AFDR group was higher than that of control group; there was no significant difference in GPT between two groups. At the 8th week after operation, blood serum Cr in AFDR group was lower than that of control group., Conclusion: When AFDR is used in the repairing of bone defect for 2-4 weeks, it may affect the level of ALP, Ca, P, and without toxicity to liver and kindey.

This article reports the treatment of a patient suffering from full-thickness electric burn of skull combined with cerebral contusion and intracranial infection to provide experience in treating such patients. Based on detailed analysis on patient's condition and CT results, several operations of surgery and anti-infection treatment were performed on the patient. The wounds healed 6 weeks after injury. The skull defect was repaired with three-dimensionally reconstructed titanium mesh of computer-aided design two years after wound healing. The treatment of full-thickness electric burn of skull combined with cerebral contusion was quite difficult. The timing and mode of operation were very important. Perioperative prevention and treatment of intracranial infection were essential to save the life of the patient. In the event of intracranial infection, effective systemic use of antibiotics, cerebrospinal fluid drainage, intrathecal injection of drugs, and the application of other comprehensive measures could ensure the success of treatment.

Objective: To investigate the surgical therapy of midline skull defect accompanied with frontal sinus injury., Methods: 11 cases with midline skull defect accompanied with frontal sinus injury were treated. Free temporal fascia was transplanted to close the top of frontal sinus after curettage of the frontal sinus wall. Then titanium prostheses were used to repair the skull defects at the same stage in 10 patients. 1 patient received skull defect repair at the second stage operation., Results: Good results were achieved in 10 cases. The titanium prosthesis had to be taken out in one case due to frontal sinusitis and the anastomosis of frontal sinus and nasal cavity was performed., Conclusions: In patients with midline skull defect accompanied with frontal sinus injury, free temporal fascia could be used to close the top of frontal sinus after curettage of frontal sinus wall. If there is no infection or mild infection in frontal sinus, the skull defect repair could be performed in the same stage. If there is severe frontal sinusitis, the defect repair should be done at the second stage.

Objective: To investigate the feasibility of using human umbilical cord blood derived mesenchymal stem cells (UCB-MSCs) and demineralized bone matrix (DBM) scaffolds to repair critical-sized calvarial defects in athymic rats., Methods: Human UCB-MSCs were isolated, expanded and osteogenically induced in vitro. Osteogenic differentiation of UCB-MSCs was evaluated by Alizarin Red staining and measurement of calcium content respectively, and then the cells were seeded onto DBM scaffolds. Bilateral full-thickness defects (5 mm in diameter) of parietal bone were created in an athymic rat model. The defects were either repaired with UCB-MSC/DBM constructs (experimental group) or with DBM scaffolds alone (control group). Animals were harvested at 6 and 12 weeks post-implantation respectively, and defect repair was evaluated with gross observation, micro-CT measurement and histological analysis., Results: Micro-CT showed that new bone was formed in the experimental group at 6 weeks post-implantation, while no sign of new bone formation was observed in the control group. At 12 weeks post-transplantation, scaffolds had been degraded almost completely in both sides. It was shown that an average of (78.19 +/- 6.45)% of each defect volume had been repaired in experimental side; while in the control side, only limited bone formed at the periphery of the defect. Histological examination revealed that the defect was repaired by trabecular bone tissue in experimental side at 12 weeks, while only fibrous connection was observed in the control group., Conclusions: Tissue-engineered bone composed of osteogenically-induced human UCB-MSCs on DBM scaffolds could successfully repair the critical-sized calvarial defects in athymic rat models.

This study was aimed to develop nano-hydroxyapatite/type I collagen artificial bone scaffold and investigate its structure, osteogenic ability and biocompatibility in vivo. According to biomimetic and self-organization mechanism, nano-hydroxyapatite/type I collagen artificial bone scaffold was developed with nano-hydroxyapatite and pure type I collagen. General observation, scanning electron microscope, porosity measurement and X-ray diffraction were used to analyze the scaffold. In vivo test, the model of rabbit skull with two defects was created, the scaffold was embedded in one defect, and another defect served as vacuity control. The in vivo study involved 12 rabbits. At 2, 4, 8 and 12 weeks, the rabbits were sacrificed in sequence and specimens were obtained for histological observation. Nano-hydroxyapatite/type I collagen artificial bone scaffold was similar to sponge under microscope, the pore size was 100-300 microm, the average ratio of porosity was 92.6%, and the inner structure was homothetic to the natural bone. No acute or chronic immunologic rejection was observed in vivo. The rabbit skull defect was repaired by nano-hydroxyapatite/type I collagen artificial bone scaffolds completely in 12 weeks. Nano-hydroxyapatite/type I collagen artificial bone scaffold structure was homothetic to natural bone structure, and had excellent osteogenic ability, biocompatibility, osteogenesis and suitable degradation.

Objective: To investigate the effect of tissue engineering bone compounded in vitro by nano-hydroxy-apatite/collagen/polylactic acid (nHAC/PLA) and recombinant human bone morphogenetic protein 2 (rhBMP-2) in repairing rabbit critical calvarial defects., Methods: Forty-eight New Zealand rabbits, weighting 2.0-2.5 kg, were made the models of critical cranial defects (15 mm in diameter) and divided into 4 groups randomly. Defects were repaired with auto-flank bone in the positive control group; with no implant in the blank control group; with nHAC/ PLA in the negative control; and with active nHAC/PLA(AnHAC/PLA) in the experimental group(the average quality of each AnHAC/PLA absorbed rhBMP-2 was 1.431 mg). The reapir results were observed through X-ray,HE dyeing and Masson's trichrism dyeing after 8 and 16 weeks., Results: The difference of bone formation was observed by X-ray block degree of skull defect area at 8 and 16 weeks. In the 8 th week and 16 th week, the radiopacities on cranial defect were 67.21%+/-2.06% and 86.48%+/-1.73% in the positive control group; 5.84%+/-1.92% and 9.48%+/-2.72% in the blank control group; 19.13%+/-2.51% and 35.67%+/-3.28% in the negative control group; and 58.84%+/-2.55% and 85.61%+/-3.36% in the experimental group. There were significant differences between the negative control and the positive control group, and between the experimental group and the positive control group at 8 weeks (P<0.05). There were significant differences between the negative control and blank group, and between the experiment and the blank group at 8 and 16 weeks (P<0.05). The histology observation showed that the width of bone trabecula at 16 weeks was more than that at 8 weeks and bone defect was full of bone tissue in positive control group. The bone defect was full of fibrous tissue at 8 and 16 weeks, and there was no new bone in the blank group. The bone defect was full of remnant material and fibrous tissue in the negative control group. The implanted area was replaced by the new bone at 8 weeks and the new bone was lamellar at 16 weeks in the experimental group; the residual material was less in defect area and there were more osteoblasts surrounding., Conclusion: The nHAC/PLA is a good scaffold material of rhBMP-2 and AnHAC/PLA has a good ability in repairing bone defect. So it is hopeful to be applied in the clinical repair of large bone defect.

Objective: This study was aimed to clarify the characteristics of alpha-tricalcium phosphate cements in reconstructing bone defects and the action of degradation products of cements in vitro., Methods: The defect (diameter 1.5 cm) was created in the calvaria of rabbit. Alpha-tricalcium phosphate cements were planted in the treatment groups. All groups were observed by histological examination and roentgenography. Bone marrow stromal cells (BMSc) were cultured in the degradation products of cements in vitro, and were observed by means of cytology and ALP., Results: Degradation of artificial bone, new bone formation, and osteogenesis between artificial bone particles were observed at 12 weeks after implantation. Osteoinduction was observed in vitro., Conclusion: Alpha-tricalcium phosphate cements have good biocompatibility, osteoinductivity and degradability, and are ideal bone substitute material for reconstruction.

Objective: To investigate the methods of establishing 3-dimensional skull model using electron beam CT (EBCT) data rapid prototyping technique, and to discuss its application in repairing cranio-maxillo-facial trauma., Methods: The data were obtained by EBCT continuous volumetric scanning with 1.0 mm slice at thickness. The data were transferred to work-station for 3-dimensional surface reconstruction by computer-aided design software and the images were saved as STL file. The data can be used to control a laser rapid-prototyping device (AFS-320QZ) to construct geometric model. The material for the model construction is a kind of laser-sensitive resin power, which will become a mass when scanned by laser beam. The design and simulation of operation can be done on the model. The image data were transferred to the device slice by slice. Thus a geometric model is constructed according to the image data by repeating this process. Preoperative analysis, surgery simulation and implant of bone defect could be done on this computer-aided manufactured 3D model. One case of cranio-maxillo-facial bone defect resulting from trauma was reconstructed with this method. The EBCT scanning showed that the defect area was 4 cm x 6 cm. The nose was flat and deviated to left., Results: The 3-dimensional skull was reconstructed with EBCT data and rapid prototyping technique. The model can display the structure of 3-dimensional anatomy and their relationship. The prefabricated implant by 3-dimensional model was well-matched with defect. The deformities of flat and deviated nose were corrected. The clinical result was satisfactory after a follow-up of 17 months., Conclusion: The 3-dimensional model of skull can replicate the prototype of disease and play an important role in the diagnosis and simulation of operation for repairing cranio-maxillo-facial trauma.

Objective: To evaluate repair of critical-sized cranial defect with tissue engineered bone fabricated by coral, bone mesenchymal stem cells (MSCs) and sustainedly released recombinant human bone morphogenetic protein 2 (rhBMP-2) by collagen., Methods: Three scaffolds of rhBMP-2 + coral, collagen + rhBMP-2 + coral and MSCs+collagen+rhBMP-2+coral were fabricated. Forty New Zealand rabbits were made the models of critical-sized defects and divided into 5 groups according to different implants: group I, auto-ilium; group II, coral; group III, rhBMP-2+coral; group IV, collagen+rhBMP-2+coral; and group V , MSCs+collagen+rhBMP-2+coral. Repair of bone defect was evaluated after 8 and 16 weeks of implantation by gross observation, X-ray, HE staining and Masson's trichrome staining., Results: Repair of bone defect in group V was similar to that in group I, and was better than that in group IV; and group III was worse. The gross appearance showed that defect region filled with bony tissue which had similar strength to adjacent bone and formed bone union with surrounding bone. The X-ray result displayed high radiopacity (80.45% +/- 2.52% in the 16th week). Histological observation showed new lamellar bone tissue and with few pore blank area. However, only transparent fibrous tissue filled the defect in group II., Conclusion: Collagen may be a suitable sustained release system for rhBMP-2. And MSCs may have important effect on enhancing repair of bone defect. Tissue engineered bone fabricated by MSCs+collagen+rhBMP-2+coral may be a useful material for bone defect repair.

Objective: To investigate the morphology and biomechanics of in vivo osteogenesis 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 with alginate 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 few bone granules and some residuary alginate gel. The percentage of bone formation area was 40.92% +/- 19.36%. The maximum compression loading on repairing tissue of defects was 37.33 +/- 2.95 N/mm; the maximum strain was 1.05 +/- 0.20 mm; and loading/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/strain ratio was 24.95 +/- 12.40 N/mm. In group B, the skull defects were mainly repaired by membrane-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 +/- 0.31 mm; and the loading/strain ratio was 19.90 +/- 5.47 N/mm. In group C, the maximum compression loading was 41.55 +/- 2.52 N; the maximum strain was 0.95 +/- 0.17 mm; and the loading/strain ratio was 47.57 +/- 11.22 N/mm., Conclusion: The plastic engineered bone prefabricated with alginate gel-osteoblasts-bone granule may shape according to the bone defects and has 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.

To investigate the ability of composite graft of osteobalsts and deproteinized bone-titanium mesh (DPB-TM) scaffold to repair cranial bone defect. 30 rabbits were randomly divided into 3 groups. The passage 3 fetal rabbit osteoblasts were seeded into porous DPB-TM scaffolds at the density of 5 x 10(6) ml(-1) as the experimental group. The same defects were respectively reconstructed by DPB-TM or osteoblasts as the control groups. After 12 weeks, the result was evaluated by three-dimensional computed tomographic scanning, gross inspection, scanning electron microscopy, histological examination and mechanics test, respectively. In the experimental group, bone trabecula was observed to pass the defect and interface was mixed. No demarcation between the region of the bone defect and the normal bone was observed. There was plenty of new bone on the scaffold. Part of the scaffold was absorbed. In view of mechanics, the intensity of artificial bone (18.93+/-1.12 MPa) was higher than that of normal bone (16.96+/-1.60 MPa) (P<0.05). In the control groups, only fibrous tissue was observed in the defect region, there was no new bone formation. The tissue engineering bone constructed by osteoblasts and DPB-TM scaffold can be applied to the repair of bone defect.

Objective: To study the application of one-stage operation of ventriculo-peritoneal shunt and cranioplasty for hydrocephalus complicated by skull defect., Method: The clinical records of 54 patients with hydrocephalus complicated by skull defect treated with one-stage operation of ventriculo-peritoneal shunt and cranioplasty were reviewed in comparison with those of 30 patients receiving two-stage operations., Result: The clinical outcome of the patients receiving the two surgical procedures did not differ significantly, but two patients undergoing one-stage operation required replacement of the shunt pump due to elevation of intracranial pressure. Implementation of one-stage operations shortened the length of hospital stay and reduced the expense of patients., Conclusion: Hydrocephalus in combination with skull defect can be treated generally with one-stage operations and care must be taken in choosing adequate shunt tube according to the intracranial pressure measured preoperatively.

Objective: To investigate the clinical application of self-cranial bone powder in one stage cranioplasty., Methods: From October 1999 to December 2002, self-cranial bone powder and medical adhesive were used to repair the skull defect, for one stage cranioplasty, caused by operations on cranium in 128 cases of severe dangerous craniocerebral injury, acute intracranial hematome, sick skull and intracranial tumor. The bone growth was observed by CT or X-ray examination 3-24 months after replantation of cranioplasty., Results: The decompression and cranioplasty were performed simultaneously, the time prolonged 5-10 minutes than that of routine, the appearance of repaired cranial bone was normal, without concavity and convexity. After 12 months of operation, the replanted bone merged with the normal bone completely, with normal appearance. The operation successful rate was 96.1% (123/125) without any complication. Only five cases were not better in growing because of less bone powder, but without cerebral pulse and defective syndrome. All the cases did not need secondary cranioplasty., Conclusion: The effect of cranioplasty with self- cranial bone powder effect is good in taking shape. This new method can avoid the traditional secondary cranioplasty for skull defect and complications.

Objective: To study the effects of artificial bone composite of bicoral, rhBMP-2 and PLA in repairing calvarial critical-size defects., Methods: Calvarial defects in 24 rabbits were surgically made and then half of the defects were repaired with the artificial composite bone. Another half of them were repaired with bicoral/PLA composite and served as controls. Four rabbits in each group were sacrificed at 4, 8, 12 weeks after operation, respectively. The treatment effects were evaluated with scanning electron microscopy and mechanical strength testing., Results: New bone was observed not only in the periphery, but also inside the artificial bone in both groups, but earlier and more new bone formation was observed in treatment group compared with control group. The mechanical strength test showed that the artificial bone in two groups, which had same mechanical strength before implantation, had significant different mechanical strength after operation. The strength of the artificial composite bone was higher than that of controls and was same with normal rabbit calvarial bone., Conclusion: The artificial composite bone possess a highly repairing ability, and the healing in bone defects may be accomplished by both osteoinductive and osteoconductive mechanism. The material may be used as a good substitute for bone grafting.

Objective: To explore the distribution and effect of endogenic bone morphogenetic protein (BMP) in repairing rabbit skull with tissue engineered bone., Methods: The autologous osteoblast-like cells were instantly implanted onto polyglycolic acid (PGA) matrix coated with collagen. The rabbit skull defect models were established by resection of bilateral 1.5 cm x 1.0 cm full-thickness parietal bone in 18 New Zealand rabbits, which were randomly divided into two groups. In one group, the composite of osteoblast- like cells and PGA matrix were grafted into the defect on one side of the skull as experimental group I, leaving the same defect area on the other side as control group without any graft implanted. In the other group, simply PGA was done in the same way as experimental group II. The tissue samples were harvested at 3, 8 and 14 days postoperatively and examined by histological and immunohistochemistry methods. The concentrations of BMP in different regions of the samples were measured using computer image analysis system., Results: After 3 days of operation, the BMP positive cells were found in the matrix of experimental group I. At 8 days postoperatively, the formation of new bone on experimental group I was prior to that of experimental group II and control group. On the 14th day, bone trabecula was formed on the experimental group I, but there was only fibrous tissue on control group. The concentration of BMP on the experimental group I and II were higher than that of corresponding region on control side., Conclusion: The osteoblast-like cells instantly implanted onto PGA matrix can synthesize and secrete BMP. It may be one of the reasons of tissue engineered bone inducing new bone regeneration that localizing endogenic BMP in bone defect area, increasing the concentration of endogenic BMP and improving its distribution by tissue engineering technique.

Since November 1996, 20 cases of craniofacial deformities, either from congenital or traumatic, were treated with MEDPOR surgical implant made from a linear high density polythylene. The animal experiment had shown that the MEDPOR had good organotrophic characteristics allowing tissue ingrowth. The biocompatibility studies in vitro and in vivo had shown that the MEDPOR biomaterial was free from any observable systemic or cytotoxic effect. In the clinical application, it was found that the MEDPOR could be easily modeled and maintained. Because of the ability to induce tissuee ingrowth, the tenacity and stability of the material were enhanced. A total of seven cases of cranial defects, 8 cases of periobital defects or depressed periobital regions, 2 cases of traumatic auricular defects, 2 cases of traumatic saddle nose and 1 case of maldevelopment of mandible angle were treated. All of the cases were followed up for 6 months, the results were satisfactory.

The skull defects with neogenetic bone were repaired with a method in which the neogenetic bone, the cranial periosteum were sutured and fixed to a Ti-net. Totally 60 children were treated. This method has following advantages: 1. Averting trephining of skull to reduce blood loss and the possibility of brain injury: 2. The neogenetic bone is well protected so that it would grow more normally; 3. The method is easy and the operation time is shortened; 4. There is little reaction and postoperative results are satisfactory. The paper describes the principle and technic of the method.

From 1990 to 1993 eight patients suffering from extensive deep burn of scalp with full-thickness necrosis of calvarial bone were treated. The intra-cranial damage following electrical injury or prolonged contact with heat source, and the extent of skull necrosis were delineated by CT and bone scanning. Primary coverage of the exposed calvarial bone using musculo-cutaneous flap or free skin flap was done, leaving the necrosed skull in situ to serve as a scaffold of "creeping substitution" for bone regeneration. Primary healing of the wound was achieved in four cases. Three cases required an average of 2.6 times of curettage or excision of the infected bone. None of the cases required a late reconstruction of the skull in this group.

We have successfully treated 4 patients with large cranial defects using a composite of allogeneic cranial bone, BMP (bone morphogenetic protein), pedicled periosteum and skin flap. The size of the cranial defects ranged from 9 cm x 7 cm to 13 cm x 11.5 cm. One to two years' follow-up showed that the wounds in all patients healed primarily with good appearance. The allogeneic bone graft was absorbed and substituted by new bone formation.

Early repair was done on 10 patients, of whom there was necrosis of either the outer or both outer and inner tables of the skull as a result of deep burn injuries. Multiple drill holes were made through the necrotic cranial bones until bleeding occurred on 7 PBD. The wounds were immediately covered with skin flaps. A continuous drip of lidocaine, chloramphenicol and normal saline was instituted underneath the flaps. The results after one to five years follow-up were satisfactory.

From Jan. 1970 to Feb. 1989, 10 cases of severe electrical burns of the skull were treated. There were necroses of the full skull bone layer and skin in 4 cases and necroses of the skull skin and external skull bone layer in 6 cases. Cure in 8 cases and death in 2 cases. The authors consider that in the early-stage protecting and reserving the skull intact is important. Repairing wound with full-circulatory skin flap or myocutaneous flap is a reasonable selection. In the later-stage, the wound may be repaired with skin graft on the granulating wound after removing the necrotic bone.

Cranioplasty usually performed in case of skull defect after craniocerebral injuries. Plexiglass or metal plate were used frequently in our country. This article introduces a new kind of material--bone cement--for skull restoration. 152 cases of skull defects were repaired by bone cement in our clinic. The advantages as below: (1) Bone cement is easy to mould and good in cosmetic result; (2) It's mechanical functions are reliable; (3) Less irritant to the surrounding tissues. The procedures of the operation and principles in utilizing this material were present in detail.