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Objective To evaluate the quality of life in patients with moderate or large cranial bone defects before and after late cranioplasty. Methods Authors performed a prospective clinical trial including all consecutive patients that filled inclusion criteria during a period of 1 year. All patients answered the quality of life SF-36 questionnaire in 5 different times. Besides authors gathered information about the primary trauma and demographic characteristics. Results A total of 70 consecutive patients were admitted to the hospital during the study period, and 62 were included in the project. Cranioplasty statistically improved patients' quality of life in all 8 domains after a 24 months follow-up. Conclusion Cranioplasty has a significant impact over the quality of life in brain trauma victims who survived the primary trauma and harbor a large cranial bone defect.

This study was conducted in order to investigate biological compatibility of a thin and flexible hydroxyapatite (HAP) paper which consists of ultralong hydroxyapatite nanowires. Circular-shaped cranial bone defects with a diameter of 8.8 mm were prepared to expose the dura maters in Wistar rats. The similar-sized, circular-shaped HAP paper was placed at the bottom of the bone defects. After 2, 4, and 8 weeks, the rats were sacrificed, and the experimental sections were examined by micro-CT scanning and histological observation. The HAP paper covered with fibrous tissues showed no inflammatory cell infiltration, and their thicknesses decreased over time. Tartrate-resistant acid phosphatase-positive osteoclast-like cells were induced around the edges of the HAP paper along with the exfoliation of the HAP paper. The newly-formed bones were observed in the bone-defected areas, either with a direct contact with the HAP paper or through thin fibrous tissues. The HAP paper-induced osteoblast differentiation was confirmed since the alkaline phosphatase activities were detected on the surfaces of the HAP paper. These results indicated that the HAP paper may induce osteogenesis without causing any harmful effects. The highly flexible HAP paper can contribute to further development of bone regenerative therapy.

Purpose We carried out guided bone regeneration of cranial bone defects in rats using the bovine bone substitute Bio-Oss and a collagen membrane and performed histological observations of the bone repair process. Materials and methods Bone defects were created in the cranial bones of 30 15-week-old Sprague-Dawley rats. We made 3 groups. A is unfilled, B is Bio-Oss, and C is Bio-Oss plus a collagen membrane. At 4 or 8 weeks postoperatively, tissue samples were taken. The Kawamoto technique was used for histological evaluation. Results There was no new bone formation in group A. In groups B and C, new bone formation was evident around the Bio-Oss. In group C, new bone formation was evident in the centers of the bone defects, detached from the cut edge of the cranial bone. Conclusion Our results suggested that the Bio-Oss acts as a scaffold for bone repair, and the use of a collagen membrane may anchor the Bio-Oss closely to the cranial bone and assist the bone repair response.

Calvarial bone defects are due to cranial bone removal at the end of the surgery (decompressive craniectomy), either because of bone involvement of the tumor or as a method to relieve intracranial pressure caused by important cerebral edema secondary to large tumors or traumas. With the progress of biomedical technology, new materials are available for use by surgeons. The titanium mesh implant is a plating platform with a matrix design and MRI compatibility that can be easily shaped, cut, and bent by the surgeon according to the bone defect. It is locked in place by several screws tapped into the bone. Although may different type of materials are currently available there is no consensus for the best method to be used. The aim of this study was to report our experience with titanium mesh implants for cranial repair and reconstruction of bone anatomy.Twenty four patients with decompressive craniectomies that required reconstruction of the calvarial bone defect for which a titanium mesh cranioplasty was used, operated in our Neurosurgery Department between January 2013 and April 2016 where included in this retrospective study. Of the 24 patients, only one had a localized infection complication for which the patient was re-operated and the implant removed with no other complications. No other neurological, infectious and functional complications were observed during or after surgery. All other patients had excellent anatomic and functional results with a positive feedback for the aesthetic aspects of the implant. The use of these bio-compatible materials is a viable, safe and reliable solution for the management of cranial bone defects offering the surgeon a large array of options for the benefit of the patient. It has a proven cost-effectiveness when compared to other customized prosthetics with the same outcomes. The MRI compatibility was proven very useful, especially for neoplasm patients who required frequent cranial imaging follow-ups, and reduced operating time was particularly beneficial to elderly patients.

Objective: To evaluate in vivo application of a new surgical mesh knitted of the TiNi-based filament as a graft substitute for the repair of cranial defects in a rabbit model. Materials and methods: The study was carried out in 69 male rabbits. Full-thickness excisional wounds of 15.0 by 15.0 mm were bilaterally created in the parietotemporal area by symmetrical dissection, leaving the dura mater intact. The lesion was treated by the knitted TiNi mesh graft (KTNM) that has been preoperatively laminated by twice-folding. Four groups were assigned: animals were grafted with the KTNM made of 40 μm (Group I), 60 μm (Group II), and 90 μm (Group III) thick TiNi-based filament, whereas in the sham-surgery control Group IV defects were left unrepaired. For histomorphological examination of the in vivo osteogenic capability, samples were taken at 7, 14, 21, 28 and 35 days postoperatively. Three series of studies in each experimental group and 3 cases in the control group (total number of cases—135) have been histomorphologically evaluated. Results: The diameter of a filament used in the KTNM fabrication has no significant impact on the osteogenic ability, but nonetheless, Group I tended to has rapid regeneration in histological assessment. In all experimental groups, an organotypic stratified-spongy osseous tissue was noted to form in the periphery layers, whereas the compact, semi-mature connective tissue was detected within the core horizons by the end of the study. A newly formed bone-KTNM interface was noted to modulate and facilitate the regenerative process therein observed, which enables us to expect that anatomical and functional features of the brain, cranium and dura mater can be completely restored by osseous wound-healing. Conclusion: These findings thus shed light on the promising tissue-engineering approach and unsophisticated surgical technique utilising KTNMs, which can repair even large skull lesions.

Autologous bone flaps adequately preserved can be used successfully for repair of cranial bone defects with biological and economic advantages. However, the effect or advantages of cryopreservation of autologous bone flaps using cryoprotectant solutions have not been investigated. The aim of this study was to investigate the utility of autologous bone flaps frozen with glycerol in cranioplasty after decompressive craniectomy.We evaluated postoperative complications and clinical and aesthetic results in 40 consecutive patients who underwent delayed cranioplasty using autologous bone flaps frozen with glycerol following decompressive craniectomy between 2001 and 2010. Bone flaps removed at the time of external decompression were dipped in 20 % glycerol solution with a sterilized plastic vessel and stored at -84 °C in an ultra-low temperature freezer. The bone flaps were thawed in the vessel at room temperature for 12 h. The bone flaps were taken out of melting glycerol, replaced in their original positions, and fixed with silk sutures or titanium plates. Follow-up periods ranged from 35 to 3745 days (median, 558 days).Mild resorption of the bone flap occurred in one case. However, there were no cases with local infection and no cases requiring reoperation for complications during the follow-up period.Cryopreservation with glycerol is a simple and safe method for preservation of autologous bone grafts. The clinical and aesthetic results of delayed cranioplasty using autologous bone flaps frozen with glycerol solution were satisfactory.

Using mouse model of regeneration of critical size cranial defects, we studied combined effect of 1 and 10 μg of BMP-2 of prokaryotic origin and recombinant erythropoietin (Epostim) injected subcutaneously in the area of bone defect in a total dose of 6000 U/kg. Erythropoietin considerably improved quantitative and qualitative characteristics of the bone tissue in the site of implantation when used in combination with BMP-2 in both concentrations.

Purpose: Xenografts can be used in dentistry and medicine for both clinical and experimental purposes. The goal of the investigation was to observe the short-term bone building outcomes of two xenografts (Gen Os and Gel 40) in the cranial bone defects in rats. Methods: Twelve rats were divided into two groups randomly, and a total of 24 parietal bone defects were created on the parietal bones. The symmetrical defects were in the critical size 5 mm and circular, which were treated with Gen Os in group 1, with Gel 40 in group 2, and symmetrical defects left empty as the controls. Rats were sacrificed 40 d after surgery, and the block sections, including the defects, were removed. The bone formation was assessed both histologically and histomorphometrically. Results: There was more bone building in the test groups when compared to the controls (p 0.05). A significant difference was also found among the three groups regarding the inflammation scores (p

Bone paté is used to repair cranial bone defects. This material contains bone-dust collected during the high-speed burring of the cranium. Clinical and experimental studies of bone dust, however, have shown that it does not have biological activity and is resorbed. We describe the use of bone paté using particulate bone graft. Particulate graft is harvested with a hand-driven brace and 16mm bit; it is not subjected to thermal injury and its large size resists resorption. Bone paté containing particulate graft is much more likely than bone dust to contain viable osteoblasts capable of producing new bone.

Objective To compare the use of Bone Marrow adult Stem Cells (BMSCs), differentiated in vitro into osteoblasts, associated to calcium phosphate versus autogenous bone graft, in the repair process of critical size bone defects. Materials and method On 36 Wistar adult rats, bilateral full-thickness defects on parietal bone were created. The defects were either repaired with calcium phosphate (group I), calcium phosphate + (BMSCs) (group II) or autogenous bone graft (group III), and the opposite side with blood clot (Control Group). In all cases a collagen membrane was used. The animals were sacrificed at 30 and 60 days, and all specimens were collected for further histological and histomorfometric study. Results At 30 days, group III (autogenous bone graft) evidences a statistical difference on bone formation when compared to the experimental and control groups ( p ≤ 0.05). At 60 days group II (BS + BMSCs) and group III (autogenous bone) showed a similar bone formation and has only a statistical difference when compared to group I (BS) and control group. Conclusion The use of calcium phosphate in conjunction with BMSCs resulted in a similar behavior in the process of bone repair in critical size defects, when compared with autogenous bone graft.

Adams-Oliver syndrome is a rare disorder with varying degrees of scalp and cranial bone defects as well as limb anomalies, which can range from mild to more pronounced manifestations. In mild cases, closure of these defects can be achieved with a conservative approach. However, surgical closure is recommended in cases where the defect is extensive and includes cranial involvement. Several complicated cases of Adams-Oliver syndrome have been reported, in which flap failures were encountered and other alternatives had to be used to close critical scalp defects. Here, the case of a 4-year-old child with Adams-Oliver syndrome and a complex cranial defect with exposed titanium mesh is described. The patient was successfully treated with epidermal growth factor (EGF) infused foam dressings and subsequent split-thickness skin grafting. The EGF has been highlighted for its essential role in dermal wound repair through the stimulation of the proliferation and migration of keratinocytes, and showed accelerated wound healing when used in partial or full-thickness skin wounds.

Preserved autologous bones are often used in staged cranioplasty. However, infected, contaminated, and tumor-bearing bones cannot be used. Another option is to use alloplastic materials. However, they should be avoided in growing children because they do not expand as the child grows and can result in bone fractures and deformation. Since a preserved skull, if available, would be resorbed, fresh autologous bones are the best option for cranioplasty in children. However, the amount of available fresh bones is limited. Thus, it is difficult to cover large skull defects in pediatric patients with fresh autologous bones. To address this, Takumi developed and reported a novel procedure called “catcher’s mask cranioplasty” for children with an open head injury in 2008.1 This approach generates esthetically satisfactory results and excellent structural integrity despite employing a relatively small amount of grafts. We report here the cases and long-term (>10 years) outcomes of 2 children who underwent this surgery.

Bone morphogenetic proteins (BMPs) have played a central role in the development of regenerative therapies for bone reconstruction. However, the high cost and side-effect profile of BMPs limits their broad application. Oxysterols, naturally occurring products of cholesterol oxidation, are promising osteogenic agents alternative to BMPs. The osteogenic capacity of these non-toxic and relatively inexpensive molecules has been documented in rodent models. We studied the impact of Oxy49, a novel oxysterol analogue, on the osteogenic differentiation of rabbit bone marrow stromal cells (BMSCs). Moreover, we evaluated the capacity for in vivo bone regeneration with Oxy49 in rabbit cranial bone defects. We found that rabbit BMSCs treated with Oxy49 demonstrated differentiation along osteogenic pathways, and that complete bone regeneration occurred when cranial defects were treated with Oxy49. Collectively, these results demonstrate that Oxy49 has the ability to induce osteogenic differentiation in rabbit BMSCs with an efficacy comparable to that of BMP-2 and to promote significant bone regeneration in cranial defects. Oxysterols may be a viable novel agent in bone tissue engineering. Copyright © 2016 John Wiley & Sons, Ltd.

Methodologies that improve estimation of caliber from cranial bone defects are necessary to meet the ever increasing admissibility standards. The relationship between caliber, wound diameter, and bone mineral density (BMD) was examined. The formation of the permanent cavity is influenced by bullet yaw, velocity, distance, and tissue properties. The hypothesis was that including BMD, wound diameter could be explained by differences in caliber. The sample consists of 68 autopsy sections and 101 specimens from Phelps (1898). A subsample of 18 was scanned using dual energy x-ray absorptiometry (DEXA) for BMD measurement to test whether an increase in BMD affects wound diameter. Pearson product-moment correlations of the subsample indicate the strongest correlation is between BMD and minimum diameter (r = 0.7101), followed by a correlation between minimum diameter and caliber (r = 0.6854). Despite the previous use of thickness as a proxy for BMD, no correlation was found between BMD and thickness (r = 0.0143). A multivariate analysis of variance (MANOVA) detected a significant influence of BMD and minimum diameter on caliber size (Prob > F = 0.0003). The logistic regression shows that caliber can be estimated from minimum diameter. Using the subsample, the results show that the inclusion of BMD strengthens the model for estimating caliber from entrance gunshot defects.

Summary Introduction Calvarial bone graft is widely used in cranio-maxillo-facial surgery. But the main sequel is an unsightly depression of the donor site. Reconstruction of the donor site using biomaterial could decrease this depression. The aim of this retrospective study was to evaluate the tolerance of biomaterials and the esthetic result of reconstruction. Patients and methods During a 24-month period, 18 patients were reconstructed with Hydroset™ cement after calvarial bone harvesting. They were followed up for 24 months. The clinical tolerance and esthetic result were assessed, using a questionnaire. Results There were neither complications nor residual pain. One patient complained of esthetic impairment. A feeling of depression on touch persisted in 44% of patients. Ninety-eight percent of patients would accept another calvarial graft if needed. Discussion Hydroset™ is well tolerated. It improves local esthetics by filling cranial bone defects after calvarial bone harvesting.

Autogenous bone grafts have frequently been used in the treatment of bone defects; however, this procedure can cause clinical complications after surgery. Besides, the amount of available bone is sometimes insufficient. Therefore, synthetic biomaterials have been researched as an alternative to autogenous bone graft implants. The objective of this study was to evaluate the repair of bone defects treated with compact autogenous bone graft or porous calcium phosphate ceramics. Three defects 3 mm in diameter were produced in the skull of 21 rats. One the defects was produced in the frontal bone, which remained empty, while the others were produced in the right and left parietal bones, which were filled respectively with ceramics and autogenous bone graft. The animals were sacrificed 1, 2, 4, and 24 weeks after surgery and analyzed by light microscopy and radiography. In the twenty-fourth week, the defects filled with autogenous bone graft and ceramics had similar volumes of newly formed bone tissue. The ceramics offered favorable conditions to bone tissue growth. Thus, we concluded that the calcium phosphate ceramic implant proved to be effective in repairing defects produced in the skull of rats.

Purpose: Platelet-rich plasma (PRP) is a novel method for transferring autogenous growth factors to the wound area. The aim of this study was to evaluate the efficacy of double-application of PRP (DA-PRP) on bone healing in rabbit cranial defects by examining osteonectin (ON) and osteocalcin (OC) expression. Materials and Methods: Twenty-eight rabbits, each with two surgically prepared calvarial bone defects, were included in this study and divided into six groups: The defects (N=56) were treated with either a single-application of PRP (SA-PRP) (n=10), a combination of SA-PRP and beta-tricalciumphosphate (SA-PRP+beta-TCP) (n=10), only DAPRP (n=8), both DA-PRP and beta-tricalciumphosphate (DA-PRP+beta-TCP) (n=8), only beta-tricalciumphosphate (beta-TCP) (n=10), or controls (n=10). The animals were sacrificed at 30th day postoperatively and samples were immunohistochemically examined for ON and OC expressions. Results: It was determined that DA-PRP did not significantly improve the ON and OC percentages achieved by SA-PRP or the controls. The three groups treated with beta-TCP showed a higher percentage of ON than those treated without beta-TCP (p

Calcium phosphate (Ca-P) cement is a well established material for bone repair. The bone biological properties of Ca-P cement can even be further improved by creating porosity in the material. The current study aimed on the evaluation of the osteoconductive behavior of porous Ca-P cement. Therefore, circular defects (6, 9, and 15 mm in diameter) were created in the cranium of 3 months old rabbits and filled with porous Ca-P cement implants. The total porosity of implants was calculated to be 71, 74 and 74% respectively and the average pore diameter was 150 microm. In addition, empty control defects were prepared. After 12 weeks implantation time the animals were sacrificed and radiographic, histological, and histomorphometrical evaluation was performed. The Critical Size Defect (CSD) of this species at this location for an implantation time of 12 weeks was confirmed to be 15 mm. Bone was observed to be present over and through almost all porous Ca-P cement implants. Only, in one out of eight animals with a 15 mm implant complete bone bridging of the defect did not occur. The size of the defect was found not to affect the total percentage of bone formation in the cement; (17 +/- 7)%, (18 +/- 6)% and (17 +/- 3)% for respectively 6, 9, and 15 mm diameter implants. We concluded that porous Ca-P cement is an excellent osteoconductive material in non weight bearing situations and complete bridging of a critical sized skull defect occurs in this rabbit model after 12 weeks of implantation.

Based on helical volume scan computed tomography (HVCT) data, it has been demonstrated previously that real-size models can be prepared with the binder-jet method with extremely high precision of various parts ranging from the outer structure of the cranio-maxillofacial bone to such fine parts as the cranial base and the orbital walls. The application of this method to clinical cases with large cranial bone defects has also been studied. The results showed the usefulness of the binder-jet method, employing starch for fixing, with which a model can be prepared faster and with less deformity caused by the weight of the material itself. Therefore, the binder-jet method is expected to attain greater clinical significance in this field.In this study the comparison between the shapes of implants before and after implantation revealed that the most important aspect of the design of hydroxyapatite (HAP) implants was determining the shapes of edges, especially its angles. That is, an implant needs very little trimming before being implanted to the patient's defective site if the shape of the edges of the implant can be designed and prepared to fix the incised bone surfaces properly. In addition, to obtain optimum results it was also shown that it is necessary to design optimal shapes of implants, taking into account thickness, porosity, and curvature, before processing the shapes of edges. It was found necessary to establish a technology and a method for producing HAP implants that perfectly fit cranial bone defects. For this purpose, it would be useful to make a template of the implants using the mirror-reversion and binder-jet methods. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 312–318, 2002

Perkembangan teknologi printer 3D untuk medis, memungkinkan aplikasi produksi implan pra-operasi dengan keunggulan akurasi geometri yang baik, mengurangi waktu operasi dan resiko kehilangan banyak darah. Teknologi printer 3D paling populer dan potensial untuk dikembangkan masal di Indonenesia adalah fused deposition modeling/FDM. Akan tetapi memiliki kekurangan: single material, jenis material terbatas dan temperatur yang tinggi sehingga tidak bisa dicampur dengan material/senyawa bioaktif yang sensitif terhadap panas. Pengembangan metode injection moulding berbasis printer 3D telah dilakukan pada penelitian ini dengan melakukan modifikasi alat, material, tahapan dan sistim produksi implan pra-operasi yang mengacu pada teknologi printer 3D untuk cranioplasty yang sudah dilakukan di negara maju. Untuk memastikan modifikasi ini bisa menghasilkan implan pra-operasi dengan akurasi geometri yang diinginkan, dilakukan karakterisasi terhadap deviasi dimensi implan yang diproduksi yaitu deviasi volume, deviasi tebal, deviasi panjang linear dan deviasi sudut kelengkungan permukaan implan, pada dua metode berbeda yang diuji, yaitu metode cranial/intra operatif dan metode injection moulding dengan menggunakan material polymethylmethacrylate/ PMMA. Hasil yang didapatkan adalah deviasi volume implan yaitu sebesar 1.87 ± 1.27 % (injection moulding) dibandingkan 11.39 ± 3.71 % (metode cranial), deviasi tebal sebesar 2.54 ± 0.86 % (injection moulding) dibandingkan 7.35 ± 1.43 % (metode cranial), deviasi panjang linear sebesar 2.61 ± 0.47% (injection moulding) dibandingkan 5.76 ± 0.79 % (metode cranial) dan deviasi sudut kelengkungan permukaan sebesar 0.98 ± 0 % (injection moulding) dibandingkan 15.45 ± 3.94 % (metode cranial). Dapat diambil kesimpulan bahwa metode injection moulding lebih baik daripada metode cranial/intra operatif. Perkembangan teknologi printer 3D untuk medis, memungkinkan aplikasi produksi implan pra-operasi dengan keunggulan akurasi geometri yang baik, mengurangi waktu operasi dan resiko kehilangan banyak darah. Teknologi printer 3D paling populer dan potensial untuk dikembangkan masal di Indonenesia adalah fused deposition modeling /FDM. Akan tetapi memiliki kekurangan: single material, jenis material terbatas dan temperatur yang tinggi sehingga tidak bisa dicampur dengan material/senyawa bioaktif yang sensitif terhadap panas. Pengembangan m etode injection moulding berbasis printer 3D telah dilakukan pada penelitian ini dengan melakukan modifikasi alat, material, tahapan dan sistim produksi implan pra-operasi yang mengacu pada teknologi printer 3D untuk cranioplasty yang sudah dilakukan di negara maju. Untuk memastikan modifikasi ini bisa menghasilkan implan pra-operasi dengan akurasi geometri yang diinginkan, dilakukan karakterisasi terhadap deviasi dimensi implan yang diproduksi yaitu deviasi volume, deviasi tebal, deviasi panjang linear dan deviasi sudut kelengkungan permukaan implan, pada dua metode berbeda yang diuji, yaitu metode cranial/ intra operatif dan metode injection moulding dengan menggunakan material polymethylmethacrylate / PMMA. Hasil yang didapatkan adalah deviasi volume implan yaitu sebesar 1.87 ± 1.27 % ( injection moulding ) dibandingkan 11.39 ± 3.71 % (metode cranial ), deviasi tebal sebesar 2.54 ± 0.86 % ( injection moulding ) dibandingkan 7.35 ± 1.43 % (metode cranial ), deviasi panjang linear sebesar 2.61 ± 0.47% ( injection moulding ) dibandingkan 5.76 ± 0.79 % (metode cranial) dan deviasi sudut kelengkungan permukaan sebesar 0.98 ± 0 % ( injection moulding ) dibandingkan 15.45 ± 3.94 % (metode cranial ). Dapat diambil kesimpulan bahwa metode injection moulding lebih baik daripada metode cranial /intra operatif.

Purpose This study aimed to evaluate ossification of cranial bone defects comparing the healing of a single piece of autogenous calvarial bone representing a bone flap as in cranioplasty compared to particulated bone slurry with and without fibrin glue to represent bone collected during cranioplasty. These defect-filling materials were then compared to empty control cranial defects. Methods Ten White New Zealand adult male rabbits had bilateral critical-sized calvarial defects which were left either unfilled as control defects or filled with a single full-thickness piece of autogenous bone, particulated bone, or particulated bone combined with fibrin glue. The defects were left to heal for 6 weeks postoperatively before termination. CT scans of the calvarial specimens were performed. Histomorphometric assessment of hematoxylin-eosin- and Masson trichromestained specimens was used to analyze the proportion of new bone and fibrous tissue in the calvarial defects. Results There was a statistically significant difference in both boneand soft tissuepresent in all the autogenous bone-grafted defect sites compared to the empty negative control defects. These findings were supported by CT scan findings. While fibrin glue combined with the particulated bone seemed to delay ossification, the healing was more complete compared to empty control non-grafted defects. Conclusions Autogenous bonegraftsinvariousformssuchas solid bone flaps or particulated bone treated with fibrin glue were associated with bone healing which was superior to the empty control defects.

The aim of this study was to assess the healing response to the bone implants treated by heating or freezing. Allogenic calvarial implants treated by heating at 65℃ for 1 hour, 3 freezes of 3 minutes, or boiling for 10 minutes (65℃, frozen and boiled group respectively) were tested for the potential to fill cranial bone defects of rabbits. Both the 65℃ and frozen groups similarly showed more than 60% of new bone formation in terms of the untreated control. Among the three treatment modalities, boiling presented the most remarkable impairment on the reparative capacity of the implants. The autogenous bone segments reimplanted to their original mandibular sites after treatment by heating at 65℃ using microwave or by freezing were revealed to similarly incorporate to the host bone in dog experiments. In summary, heat treatment at 65℃ for 1 hour is comparable with freeze treatment in terms of preservation of the regenerative potential of bone for simultaneous reimplantation., Oral medicine & pathology. 2001, 6(1), p.43-50

Hydroxyapatite ceramic implants were used in the reconstruction of very large and complex-form cranial bone defects in nine patients. The bone defects were the result of craniectomy after infections and other complications such as severe brain edema, after neurosurgery, and as a result of trauma, subdural hemorrhage, and surgery for brain tumor. The size, shape, and curvature of the hydroxyapatite ceramic implants were determined based on high-precision, full-scale models fabricated through a laser lithographic molding method by using computed tomographic data. The use of this method allowed the fabrication of hydroxyapatite ceramic implants of shapes that accurately matched the area of bone defect, allowing for a minimum of adjustment during the operation even with a complex-form implantation. Not only were good cranial contour reconstructed and aesthetically satisfactory results obtained in the cases treated by incorporating this series of techniques, but neurologic conditions present in some cases were also improved to some extent. The postoperative course has been steady for all nine patients, with no blood transfusions required during or after the operations and no implants requiring removal because of infection or other postoperative complications. The average length of postoperative hospitalization for the nine cases was 11.7 days, remarkably short considering the clinical conditions.

Cranioplasty is a medical technique to correct cranial bone defects. Depending on the size and location of the defect, a bone substitute can be used to replace the missing bone. Frontal bone defects are important to patients in terms of cosmetics because they are visible. Advances in computer design allow the production of customized implants with improved cosmetic and functional results. This report describes hybrid optimization of three-dimensional technological methods along with traditional methods toward the manufacture of deep-buried titanium implants, restoring frontal skull defects for 4 patients. A three-dimensional model was produced from the computed tomographic scan data of 3 patients using an in-house three-dimensional printer. A new approach was followed in treating the fourth patient. The defect was restored using preoperative scan before cranioplasty. These data were transported digitally into the defect skull to recreate the bone contour required, and a three-dimensional model was produced from the "new" digital model using the three-dimensional printer. Defect areas of the patients were large and measured 101.21 × 123.35 (vertical × horizontal) in average (mm). Conventional wax-up of the defect was carried to restore normal conformity. A titanium sheet (0.5 mm) was swaged into the desired shape; however, convexity of the defect area makes titanium swaging challenging, especially at the deep lateral undercuts. Making side flanges at reasonable lengths made it easy to swage without creasing. Three-dimensional models aided to produce accurately fitting plates. Finally, the sequential method of using both digital and manual procedures is a low-cost, reliable, accurate, and reproducible method.

INTRODUCTION Reconstruction of cranial bone defects is one of the most challenging problems in reconstructive surgery. The timing of reconstruction, the location of the defect, the materials to be used, and the medical history of the patient are parameters that have been mostly discussed in the literature. To the best of our knowledge, there has not been any published classification for the cranial bone defect reconstruction according to defect size. MATERIALS AND METHODS Twelve patients underwent reconstruction of cranial vault defects. Cranial bone defects were classified into 3 groups according to the size of the defect. The small-sized group included the defects smaller than 25 cm(2), the medium-sized group included the defects between 25 to 200 cm(2), and the large-sized group included the defects larger than 200 cm(2). The small-sized defects were reconstructed with split calvarial graft, demineralized bone matrix, or hydroxyapatite cement; the medium-sized defects were reconstructed with split calvarial graft or allogenic bone graft; and the large-sized defects were reconstructed with methyl methacrylate, autoclaved bone, or porous polyethylene. RESULTS Two patients needed revision for irregularities with demineralized bone matrix. Other patients had no skull defects or irregularities for which revision was suggested. CONCLUSIONS We believe that the size of the defect is important for the reconstruction of cranial vault defects and that using a standard algorithm can increase the success rate.

There are many synthetic materials for the treatment of bone defects, which have their own advantages and disadvantages. We aimed to compare the efficacy of ostrich eggshell, which is cheap and easily available, and demineralized bone matrix in healing of cranial bone defects.A full-thickness circular bone defect was created in the frontal bone of 40 Wistar rats. Group 1 was the operative control group. In group 2, demineralized bone matrix applied into the defects; in group 3, Struthio camelus (ostrich) eggshell implants (OSIs) were applied into the defects; and in group 4, ostrich eggshell powders were applied into the defects. Computed tomographic analysis was performed to evaluate the healing of bone defects, the bone density, the OSI area measurements, and the OSI volume and density. At the end of the 24th week, all rats were killed. New bone formation, infection, resorption, and tissue reactions were evaluated.Ostrich eggshell implants were slightly resorbed, integrated with bone, stable, and supplied good cranial completeness. Ostrich eggshell powders were totally resorbed at the sixth month. There were no significant differences between control and ostrich eggshell groups in new bone formation.Ostrich eggshell did not seem to be an osteoproductive material, but it has some important advantages as an implant. Ostrich eggshell has a strong structure, is cheap, is shaped easily, and does not cause tissue reaction or infection. Ostrich eggshell could be a good alternative graft material for craniomaxillofacial procedures. Further studies are required to find out the potential use of the ostrich eggshell in craniomaxillofacial reconstructions.

The possibility of using coralline hydroxy-apatite in combination with polylactide and polyglcycolic acid instead of a bone graft in the skull region is examinated. Coralline hydroxy-apatite blocks strengthened with a membrane made of a combination of polylactide and polyglycolic acid were inserted into bony defects created in 12 rabbit skulls. The blocks were observed during a follow-up of 12 months. They became fixed to the surrounding bone and no adverse effects or harmful reactions in the nearby tissues could be detected.

We studied the efficacy of tissue generated from polymers seeded with periosteal cells and compared it to that of polymers seeded with chondrocytes, for its ability to repair surgically created cranial bone defects in rats. Large (approximately 40 mm2) bilateral defects were created in the parietal and temporal bones of 20 nude rats. One defect in each mouse was filled with synthetic biocompatible and biodegradable polymer templates seeded in vitro with either bovine periosteal cells (experimental group I) or chondrocytes (experimental group II). Contralateral defects were filled with either polymer not seeded with cells (control group I), or nothing at all (control group II). There was gross evidence of new bone formation repairing the defect in 7 of the 10 defects filled with polymers seeded with periosteal cells, while 8 of the 10 defects filled with polymers containing chondrocytes showed gross evidence of new cartilage formation covering the defect. Control defects showed no gross evidence of repair with either bone or cartilage.

In this article a method for individual implant construction for facial and cranial bone defects is presented which is based on defined resection lines. Such defects resulting from tumor resections should be closed immediately to protect the brain. To combine resection and reconstruction in one intervention, implants have to be planned and manufactured before the surgery starts. This results in lower patient stress and lower costs. Due to complex modeling systems today, this is performed by technicians. High communication between the surgeon and technician is required. A workflow was developed that combines the construction and treatment planning process. With this workflow an application was created that enables the surgeon to intuitively construct the implant shape indirectly by defining resection lines even in complex facial areas. This leads to direct influence on the implant shape, to more independence from a technician and finally to shorter manufacturing time. But the precondition of anatomical symmetry restricts the application area. The reduced complexity of the implant construction sacrifices the ability of having a more generic application.

We examine the 6-month histology of a quick-setting hydroxyapatite cement (Mimix), with and without absorbable plates (LactoSorb), after placement in critical size defects made in the skull of 20 New Zealand white rabbits. Two 10-mm-diameter parietal defects were made in each rabbit. One defect was placed on each side of the sagittal suture. In 10 animals, the left defect was filled with Mimix alone, and in the other 10, an absorbable plate was placed across the base of the left defect before Mimix placement. The right-sided defect served as a control in all animals, with no material placed in or across this defect. The rabbits were killed 6 months postoperatively. A bone pathologist performed histologic examinations of the specimens looking specifically for evidence of inflammatory reaction and bone formation. There was no inflammation around the dura or any other negative histologic reaction in either the study groups or the control. Growth of new bone into the Mimix was found along the periphery in all specimens. We found no migration or displacement of the Mimix from any of the calvarial defects.

The purpose of this study is to evaluation of effect on bone formation of PRP and Fibrin sealant in Bio-Oss grafts on rabbit cranial defect. Twelve rabbits were used as the animal model. Two equal 9mm diameter cranial bone defects were created in each rabbit and immediately grafted with Bio-Oss only, Bio-Oss + PRP, and Bio-Oss + Fibrin sealant. Rabbits were sacrificed at 4 and 8 weeks. New bone formation rate of grafted area were evaluated by histomorphometric analysis. No statistically significant difference of new bone formation rate was found between Bio-Oss only, Bio-Oss + PRP, and Bio-Oss + Fibrin sealant at 4 and 8 weeks (P>0.05). Adding PRP or Fibrin sealant to Bio-Oss did not show an increase of new bone formation in comparison to Bio-Oss grafting alone in cranial defect of rabbit.

Cranioplasty of cranial bone defects can generally be accomplished with autogeneous bones as well as with nonbiological materials. Autologous living-bone grafts are ideal but require sacrifice of donor bone, and synthetic materials might have possible exposure of the materials, delayed infection, and/or allergic reaction. The authors report cranioplasty with a bone graft after auto-purification by subcutaneous preservation of the contaminated bone fragment. A 47-year-old man was given a frontal cranioplasty with a split parietal bone and rib. Epidural abscess ensued, and debridement was performed to control the infection. The largest bone fragment was subcutaneously preserved in the chest wall and reused for cranioplasty. Subcutaneous preservation of bone is a promising strategy for cranioplasty after neurosurgery. The condition of the bone fragment can be inferred from the condition of the site at which it is preserved. If the bone flap is contaminated, it can be purified by the patient's immune system.

This study is one of a series in which the authors evaluate various absorbable sheets to guide bone regeneration in cranial bone defects. The aim was to evaluate the use of self-reinforced poly-L,D-lactide 96/4 (SR-PLA96) sheets for cranial bone tissue engineering in experimental defects in rabbits. Square defects of 10 x 10 mm were created in the right parietal bone. SR-PLA96 implants (15 x 15 mm) were used to cover these defects in 12 New Zealand White rabbits. Similar defects were created in the left parietal bone, but no sheets were used (controls). The rabbits were killed after 6, 24, or 48 weeks. Histology and histomorphometry were used to evaluate healing of the defects. Defects covered with SR-PLA96 sheets showed more abundant bone formation than control (non-covered) defects. At 6 weeks, the defects were occupied mainly by fibrous tissue. At 24 weeks, healing with bone formation was more obvious in the covered defects. At 48 weeks, bone completely bridged defects covered with SR-PLA96 sheets, and incomplete bridging was seen in non-covered control defects. Hence, bone tissue engineering in experimental cranial bone defects in rabbits can be achieved using SR-PLA96 sheets to guide bone regeneration.

The purpose of this study was to examine the effect of Lactosorb absorbable plates on bone healing across cranial bone defects in the rabbit skull. Two 10-mm diameter parietal skull defects were created in each of 20 rabbits, with one defect being placed on either side of the sagittal suture. In 10 rabbits, an absorbable plate was placed across both the inner and outer cortices of the left defect, and in the other 10 rabbits, an absorbable plate was placed across the outer cortex only of the left defect. The right defect always served as the control side, with no plate being placed across it. Rabbits were killed an average of 25 weeks postoperatively. Areas of reossification in the experimental and control defects of each rabbit were then measured, examined histologically, and compared. Growth across defects spanned by one plate was also compared with growth across defects spanned by two plates. Histologic and statistical analyses revealed no significant differences in reossification between the control and experimental defects in each animal and between the defects spanned by one versus two plates. This study suggests that these copolymer absorbable plates neither inhibit nor facilitate reossification across 10-mm diameter rabbit cranial defects.

Bony defects in the craniomaxillofacial skeleton remain a major and challenging health concern. Surgeons have been trying for centuries to restore functionality and aesthetic appearance using autografts, allografts, and even xenografts without entirely satisfactory results. As a result, physicians, scientists, and engineers have been trying for the past few decades to develop new techniques to improve bone growth and bone healing. In this review, the authors summarize the advantages and limitations of current animal models; describe current materials used as scaffolds, cell-based, and protein-based therapies; and lastly highlight areas for future investigation. The purpose of this review is to highlight the major scaffold-, cell-, and protein-based preclinical tools that are currently being developed to repair cranial defects.

On June 27, 1989, at the Fifth International Symposium of Plastic and Reconstructive Surgery of the Head and Neck in Toronto, Canada, Peter Costantino, MD, and Craig Friedman, MD, Chicago, Ill, presented the results of their research using a new form of hydroxyapatite in laboratory animals. A hydroxyapatite putty, whose key component is tetracalcium phosphate (Ca 4 (PO 4 ) 2 ), was studied in three experimental models using cats. Initially, solid disks of the putty were implanted intramuscularly to study the soft-tissue response. The material was well-tolerated, demonstrating no fibrous encapsulation and only minimal resorption. The hydroxyapatite putty was then used to obliterate and contour frontal sinuses, and also to fill cranial bone defects that extended to the level of the dura. There were no infections, extrusions, structural failures, or toxic reactions noted in either group. Serial histologic examinations between 6 and 18 months revealed progressive replacement of the implanted material by

In order to stimulate regenerative bone formation in adult mammals experiments were conducted in replacing cranial bone defects by ground cranial bone. In rats the homotransplanted bone grindings resolved in three weeks. In mice — more slowly — they were preserved for several months. Bone grindings stimulated transformation of local connective tissue into genuine bone tissue, and replaced cranial bone defects both in rats and mice.