Cranial Bone Grafts Research Articles

Effect of Use of Slow Release of Bone Morphogenetic Protein-2 and Transforming Growth Factor-Beta-2 in a Chitosan Gel Matrix on Cranial Bone Graft Survival in Experimental Cranial Critical Size Defect Model

Bone grafts, used for providing structural integrity of cranial vault remodeling, could not always integrate with the remaining bone structures. All efforts are focused on increasing incorporation of the applied bone grafts. Allografts were covered by chitosan so that slow release of bone morphogenetic protein-2 (BMP-2) and Transforming growth factor-beta-2 (TGF-beta-2) was achieved. Two hundred forty Wistar-Albino rats were distributed equally in 8 study groups. Study groups were designed as; defect group, autograft group, allograft group, chitosan group, allograft + chitosan, TGF-beta-2 group, BMP-2 group, and TGF-Beta-2 +BMP-2 group. Bone biopsies were obtained at second, eight, and 14th weeks. Bone regeneration was evaluated by morphologic studies detecting histologic bone healing and radiologic studies detecting bone density. Histologic findings were evaluated in 2 categories; tissue response to the implant and defect healing. Additionally, scanning electron microscopy for detailed morphologic evaluation was done. Bone density of the applied scaffold and the parietal bone at the same computed tomography section were measured in Hounsfield scale and this ratio was used for densitometry evaluations. Kruskal-Wallis test was used to analyze difference among groups according to the histologic and radiologic data. Pairwise comparisons were done using Mann-Whitney U test with Bonferroni correction. P < 0.05 was considered significant. In the morphologic studies, bone regeneration in BMP-2 group was found to be compatible with bone regeneration in gold standard autograft group and even better than it within 15 days. Chitosan is a biocompatible material. TGF-Beta-2 alone is not effective enough in bone regeneration; BMP-2 alone has a positive effect in every step of bone regeneration. Combining TGF-Beta-2 with BMP-2 does not lead to a better bone regeneration than using BMP-2 alone. A synergistic effect is not obtained by using these 2 factors together.

Spontaneous Cerebrospinal Fluid Rhinorrhea Associated With a Far Lateral Temporal Encephalocele -Case Report-

A 35-year-old female complained of right-sided watery nasal discharge persisting for 2 weeks. Neuroimaging investigations revealed a defect in the lateral side of middle cranial fossa, temporal lobe encephalocele protruding into the lateral extension of the sphenoid sinus, and cerebrospinal fluid (CSF) collection on the right side of the sphenoid sinus. The transcranial approach was performed for resection of the encephalocele and obliteration of the cranial base defect anterolateral to the foramen spinosum with transcranial multilayered closure of the defect using autologous fat, cranial bone graft, and vascularized split temporal muscle. At 1-year follow up, the CSF rhinorrhea had not recurred. Transcranial multilayered closure of the defect is safe and reliable, particularly for large CSF fistula at the far lateral sphenoid sinus.

Autogenous calvarium bone grafting as a treatment for severe bone resorption in the upper maxilla: A case report

Atrophic maxilla rehabilitation has been the subject of several studies for decades; despite this, there are still many different therapeutic choices for the best way to treat maxillary resorption in order to enable implant placement and integration. These possibilities include the optimal use of remaining bone structures, such as the pterygoid processes or zygomatic arch, which involves using zygomaticus and pterygoid implants in combination with standard implants placed in the residual bone; alternatively, regenerative techniques, alveolar bone expansion/distraction or bone grafting techniques may be used. Severe maxillary atrophy has a multifactorial aetiology; the most important factors being long evolution edentulism, hyperpneumatization of the maxillary sinus, post-traumatic deficit, bone loss after surgery (tumours, cysts) and periodontal problems or infection. In this report, we present a clinical case of onlay block reconstruction in an atrophic maxilla with harvested cranial calvarium bone grafts for successful future implant-supported oral rehabilitation.

The immunosuppression effect of cyclosporine A on the allogenic calvarial bone graft in mice

Introduction: This study examined the effect of cyclosporine A (CsA) on the allogenic cranial bone graft in the mice. Materials and Methods:Twenty eight 12-week-old male ICR mice weighing 40 g were used. The experimental group was injected subcutaneously with CsA (10 mg/kg/day) diluted in Caster oil for 7 days prior to the graft until sacrifice. The control group was injected with the same solution without CsA. Two full-thickness bone defects with a diameter of 3 mm were made with a trephine bur in the parietal bone lateral to the sagit tal suture. A calvarial defect of a mouse was grafted with allogenic calvarial bone disc from another mouse. The experimental and control groups were i njected with CsA and the solution without CsA in the same manner before surgery, respectively. The mice were sacrificed at 1 week, 2 weeks and 4 weeks after the bone graft, respectively. Results: In the experimental group, fibrous connective tissues and small amounts of inflammatory cells were observed. At 2 weeks after t he allograft in the experimental group, new bone formation in fibrous collagenous tissue and around the allogenic bone was noted. At 4 weeks after the allograft, new bone formation was active along and at the periphery of the mature allogenic bone. The proliferation of blood vessels incre ased in bone marrow. In the control group, fibrous tissues and inflammatory cells were observed around the allogenic bone and existing bone at 1 wee k. At 2 weeks after the allograft, the proliferation of blood vessels accompanied by inflammatory cells were scattered in the fibrous connective tissue s. New bone formation around the allogenic and existing bone could be observed. At 4 weeks after the allograft, inflammatory cells were severely infi ltrated around the allogenic bone. Osteoclasts were scattered along the allogenic bone and induced bone resorption. Conclusion: These results suggest that the daily administration of CsA (10 mg/kg/day) induces efficient immunosuppression without serious c omplications ,and this protocol might be useful for the experimental model of allogenic bone grafts.

Reply

Sir: The authors of “Correction of Frontonasoethmoidal Encephalocele: The HULA Procedure” appreciate the input from Drs. Foo and Bartlett of The Children’s Hospital of Philadelphia. We agree with the comments concerning (1) the importance of the earlier reports by Boonvisut of the large number of patients treated for frontonasal encephalocele, and (2) the similarities of the techniques including intracranial and extracranial approach and the need for medialization of the medial canthal bone segment. However, we did not feel that we could achieve a full correction of the deformation by merely translocating the “composite unit” medially (at least not in our hands). As mentioned in the article, the outward projection of the encephalocele mass typically caused a superiorly displaced supraorbital region and an anterolaterally displaced medial canthus. Thus, the composite unit would just translocate the original deformity medially. The HULA procedure separates the supraorbital region from the medial canthal bone segment to allow for independent movement. The supraorbital bar is lowered and the medial canthal bone segment is positioned posteromedially. It is also important to stress that although the medial canthal segment must be moved medially, we are not treating hypertelorbitism. Finally, the procedure stressed a low radix position for the nasal cranial bone graft. Citing the important work of Boonvisut’s team on frontonasoethmoidal encephalocele is warranted and adds to our article. Our published technique adds modifications that we feel improve the results after corrective surgery. Of course, variation does exist among patient deformities and among the corrective procedures. In addition, we had the unique opportunity of following and studying our mission patients during and after their recovery period. Anand R. Kumar, M.D. Department of Plastic Surgery Walter Reed National Military Medical Center Bethesda, Md. James P. Bradley, M.D. University of California, Los Angeles Craniofacial Surgery Los Angeles, Calif.

Severely Resorbed Mandible Treated by Soft Tissue Matrix Expansion (Tent Pole) Grafts: Case Report

The functional rehabilitation for severely resorbed mandibles has been a challenge for dentists and oral surgeons. We present a 2-year follow-up case of severely resorbed mandibles successfully treated by soft tissue matrix expansion and cranial bone graft with nonremovable screw-retained acrylic resin prosthesis supported by 4 dental implants.

O.608 Orbital dysplasia and plexiform neuroflbroma in NF1

Surgical reduction of fractures involving the orbits, nasoethmoid complex, and adjacent cranium is challenging; adequate initial reduction and stabilization is essential because secondary reconstructive procedures usually provide less than satisfactory results. Our operative techniques for surgical exposure, as well as fracture reduction and fixation, have evolved from standard facial incisions and wire fixation to complete exposure of the orbits, nasoethmoid complex, and adjacent cranium using an extended bicoronal approach, application of ridged plating techniques, and cranial bone grafts when needed. This evolution of surgical technique has been accompanied by an overall improvement in immediate cosmetic and functional results.

O.605 Bioactive glass in fronto-orbital and skull surgery

Surgical reduction of fractures involving the orbits, nasoethmoid complex, and adjacent cranium is challenging; adequate initial reduction and stabilization is essential because secondary reconstructive procedures usually provide less than satisfactory results. Our operative techniques for surgical exposure, as well as fracture reduction and fixation, have evolved from standard facial incisions and wire fixation to complete exposure of the orbits, nasoethmoid complex, and adjacent cranium using an extended bicoronal approach, application of ridged plating techniques, and cranial bone grafts when needed. This evolution of surgical technique has been accompanied by an overall improvement in immediate cosmetic and functional results.

Pediatric Cranioplasty Using Particulate Calvarial Bone Graft

Closure of calvarial defects in children is problematic because the supply of autologous bone is limited and alloplastic materials are not advocated. The authors previously showed that cranial particulate bone graft applied over the coronal gap during primary fronto-orbital advancement reduced the incidence of residual osseous defects. The purpose of this study was to determine the effectiveness of particulate bone graft for established calvarial defects. The authors analyzed consecutive children who had undergone cranioplasty with inlay particulate bone grafting between 1989 and 2007. Particulate bone was harvested from parietal calvaria or from the endocortex of the cranial elements using a hand-driven brace and bit. Patient records were reviewed for age at the time of cranioplasty, operative indication, size of defect, and length of follow-up. Outcome variables included persistent osseous defects, need for further cranioplasty, and complications. Thirty-eight children had inlay particulate bone grafting at an average age of 8.0 years (range, 3 to 20 years). The average defect size was 66.5 cm (range, 5 to 250 cm). Indications for inlay grafting were revision fronto-orbital advancement, bony gaps following primary cranial remodeling, congenital defects, trauma, and tumor. Mean follow-up was 6.1 years (range, 0.5 to 18 years). Three patients (7.9 percent) had small persistent osseous defects, and one (2.6 percent) required another cranioplasty. Inlay autologous cranial particulate bone graft effectively heals established cranial defects in children. Particulate bone graft can be harvested in infants and young children, does not require neurosurgical assistance, and has minimal morbidity.

Purtscherʼs Retinopathy as a Cause of Postoperative Blindness

Sir: The most frightening sequela of managing periorbital trauma is acute postoperative blindness. As such, surgeons should be aware of the causes, diagnosis, and management options for patients who develop visual loss following surgery. A 16-year-old boy with no medical history or prior visual problems sustained trauma to the head and chest in a motor vehicle accident. The orbitozygomatic trauma required open reduction and internal fixation, including the use of cranial bone grafts to the orbital floor. Postoperatively, he was followed with head elevation, iced compresses, and close observation. Light perception was recorded serially. Gentle separation of the eyelids confirmed intact vision. He initially did well and was discharged to home on postoperative day 2. At home on the fourth postoperative day, he noted a rapid decline in vision in the left eye. No tenderness, bleeding, or swelling was noted. A computed tomographic scan failed to demonstrate involvement of the nerve either by incomplete reduction or external compression. A retinal specialist determined the cause to be Purtscher's syndrome based on the history and funduscopic findings. A course of high-dose steroids was prescribed. Purtscher's syndrome is a retinopathy of vascular origin first described in the early 1900s.1,2 The hallmark is a history of severe head or chest trauma, but a similar appearance has been described with acute pancreatitis,3 fat embolism, renal failure, childbirth, and connective tissue disorders. The pathogenesis was originally thought to be extravasation of lymph from retinal vessels following a sudden increase in pressure. Since then, several causes have been suggested, including raised intrathoracic pressure, vasculitis resulting from free fatty acids, and vascular occlusion caused by emboli. Purtscher's retinopathy is characterized by multiple white patches, hemorrhages, and optic disc edema on funduscopy (Fig. 1). The white lesions (cotton-wool spots) represent retinal microinfarcts within the layer of nerve fibers. The findings may be unilateral or bilateral, and the effect on vision may be delayed for up to 48 hours after onset of the condition. Late physical findings include pigment migration and optic atrophy. The diagnosis is based on both the appearance of the fundus and the history of associated systemic injury (Fig. 2).Fig. 1.: Preoperative axial computed tomographic scan demonstrating fracture of the left zygomaticomalar complex.Fig. 2.: Funduscopic appearance of Purtscher's syndrome. (From the University of Iowa Department of Ophthalmology and Visual Sciences.)On follow-up examination at 3 months, the patient was noted to have 20/20 vision in the right eye and 20/200 in the left. A significant afferent pupillary defect was noted on the affected side. Dilated ophthalmoscopy revealed a return to a relatively normal retinal appearance despite some optic nerve pallor. At 1-year follow-up, he was noted to have a central acuity of 20/25 with persistent peripheral visual field damage. The significant recovery of partial vision over the first 6 months is consistent with the course of Purtscher's syndrome. No specific treatment for Purtscher's syndrome has been delineated. However, the use of early, parenteral, high-dose steroids and/or fenestration of the optic nerve sheath may be beneficial.4 An initial loss of vision in the range of 20/200 to hand movement visual acuity can improve over a period of months to a range of 20/30 to 20/200. It is important for plastic surgeons who manage facial trauma to be aware of this condition because early, high-dose, steroid therapy may be beneficial. Justin Lipper, B.A. Joseph Pazkowski, M.D. Peter J. Taub, M.D. Mount Sinai Medical Center New York, N.Y.

Dorsal Augmentation with AlloDerm

The augmentation-reduction principle is becoming pervasive in nasal surgery. Rhinoplasty surgeons have discovered that nasal skin does not consistently contract. Therefore, nasal augmentation is an increasingly accepted technique, and grafts are required. Autogenous cartilage is the grafting material of choice. There are drawbacks to autogenous material, especially in secondary rhinoplasty patients who are often graft-depleted. Cartilage grafts may cause unsightly irregularities over time. Therefore, an interest in alternative soft tissue substitutes has developed. AlloDerm is freeze-dried acellular cadaver dermis. AlloDerm acts as a filler to expand portions of the nasal skin envelope to balance the overresected nose and adhere to the augmentation-reduction principle. AlloDerm facilitates touch-ups, especially in the author's own personal patients. It is soft, thin, and pliable and can be placed under very thin skin. AlloDerm obviates the necessity for graft harvest. It is safe in that it can eliminate the risk of donor-site problems for dorsal onlays such as cranial bone or rib grafts. It is natural and acts as an excellent camouflage graft when used as padding over a cartilage graft. It is incorporated into the surrounding tissue and does not develop unsightly irregularities over time. Extrusion is rare. It does not shift over time. It is especially useful in donor-site-depleted patients. Overcorrection is absolutely necessary because a portion of the implanted AlloDerm is always absorbed. Resorption is most common over the bony dorsum with about 20 to 30% of the graft absorbing. Resorption is disappointing for the patient and frustrating for the surgeon. Absorption does not seem to relate to the number of layers used. No graft absorption has been noted after 1 year. Therefore, it is safe to assume that the patient has a stable result from the AlloDerm graft after 1 year, and no further change should be anticipated. It is easy to use. The advantages and caveats should be kept in mind when evaluating a patient for a dorsal graft.

Biomechanical and Histologic Evaluation of the Norian Craniofacial Repair System and Norian Craniofacial Repair System Fast Set Putty in the Long-Term Reconstruction of Full-Thickness Skull Defects in a Sheep Model

The purpose of this study was to investigate the long-term (12 months) strength and osteoconductive properties of two forms of carbonated calcium phosphate cements (i.e., the Norian Craniofacial Repair System and Norian Craniofacial Repair System Fast Set Putty) and to compare these two bone cement forms to an autogenous cranial bone graft in a full-thickness skull defect adult sheep model. Twenty-six sheep were assigned to one of eight groups (n = 3 per group). A 4.5-cm2 full-thickness defect was created in the right and left parietal bones. Reconstruction was performed with a full-thickness cranial bone autograft, the Craniofacial Repair System, or Fast Set Putty. Skull samples were harvested at day 1, 6 months, and 12 months. Biomechanical testing was performed using a vertical drop test. Although the Craniofacial Repair System and Fast Set Putty osseointegrated fully, there was little osteoconduction at 12 months. The Craniofacial Repair System was the weakest reconstruction, presenting the lowest peak force transmission and the highest displacement at 12 months. Fast Set Putty showed significantly higher values for peak force transmission and lower displacement when compared with the Craniofacial Repair System. The Craniofacial Repair System progressively lost strength over the course of this study. Fast Set Putty demonstrated greater strength and rigidity than the Craniofacial Repair System. Both implants had limited bone ingrowth from defect borders, but both cements osteointegrated completely. Bone grafts regained biostructural characteristics and strength similar to those of intact bone and clinically performed the same in this sheep model.

Cranial bone grafting and simultaneous implants: a submental technique to reconstruct the atrophic mandible

Results after treatment of severe maxillary and mandibular atrophy (Cawood classes V and VI) are often unsatisfactory and unpredictable. Reconstruction of such severely resorbed edentulous jaws represents a challenge. In maxillofacial surgery, bone grafts from the skull (split calvarial bone grafts) are commonly used for reconstruction of large bone defects of the midface. In the 1990s, various authors reported alveolar-ridge augmentation using calvarial bone grafts. This is the first report of its kind describing an extraoral approach for cranial bone grafting with simultaneous implant placement to the atrophic mandible.

Primary Grafting with Autologous Cranial Particulate Bone Prevents Osseous Defects following Fronto-Orbital Advancement

Approximately 20 percent of patients require cranioplasty for defects after fronto-orbital advancement. The authors hypothesized that corticocancellous cranial particulate bone placed over exposed dura at the time of fronto-orbital advancement would decrease the frequency of incomplete ossification. The authors retrospectively analyzed consecutive children who underwent fronto-orbital advancement for craniosynostosis between 1988 and 2006. In group I, cranial gaps resulting from frontal advancement were left open and allowed to heal spontaneously. In group II, corticocancellous particulate bone was used to fill the calvarial defects. Bone was harvested from the endocortex of the frontal segments or parietal calvaria using a hand-driven brace and bit. Outcome variables were persistent osseous defects and need for corrective cranioplasty. The study included 213 children. There were 50 patients in group I: mean age at fronto-orbital advancement was 7.0 months (range, 2 to 15 months); 12 patients (24 percent) had residual defects and 10 (20 percent) required cranioplasty. Group II contained 163 patients: mean age at fronto-orbital advancement was 14.1 months (range, 6 to 72 months); nine children (5.5 percent) had a cranial defect and five (3.1 percent) required cranioplasty. Infants in group II were less likely to have bony defects (p = 0.0005) or require cranioplasty (p = 0.0002) compared with children in group I, despite being older at the time of fronto-orbital advancement (p = 0.001). Corticocancellous cranial particulate bone grafting during fronto-orbital advancement reduces the prevalence of osseous defects and the need for secondary cranioplasty, independent of patient age.

Cranial Bone Grafts for Alveolar Reconstruction: Report of the Morbidity Associated With the Donor Site

Cranial Bone Grafts for Alveolar Reconstruction: Report of the Morbidity Associated With the Donor Site

Reconstruction of Severe Atrophic Maxilla With Inverted “L” Cranial Bone Graft and Osteotomy: A Technical Note

There are many types of bone grafts used for maxillary and mandibular reconstruction. One is cranial bone, which has been commonly used as a graft for oral and maxillofacial surgery. Psillakis et al1 reported that the average thickness of the parietal area was 5 mm (range 4-6 mm), while the study of Jung et al2 found the range of the parietal thickness from 5.037 to 7.169 mm. It is believed that this difference could be derived from racial variance.2-4 Zins and Whitaker5 reported that membranous grafts showed significantly greater maintenance of bone volume than endochondral grafts in an animal study, which supported the study of Smith and Abramson.

O.032 Interest of cranial bone grafting in nasal surgery

The treatment of complex orbital floor fractures with extensive orbital prolapse remains a surgical challenge in craniomaxillofacial traumatology and is still controversially discussed. Reduction of orbital tissue via a transcutaneous or transconjunctival approach alone can be very difficult and lead to unsatisfying results.Over a 3-year-period, we enrolled 13 patients who underwent endoscopy-assisted reconstruction of isolated orbital floor fractures via a combined subciliary and transantral approach. Patient data, imaging and ophthalmologic examination were reviewed prospectively.Ten patients underwent primary surgical treatment, 3 patients had secondary surgical treatment because of unsatisfactory results of primary surgical intervention. All patients had an uneventful postoperative course without ophthalmologic deterioration, no further surgical procedures were necessary.The additional use of an endoscopy-assisted transantral approach provides a reliable treatment modality in selected cases. To our knowledge, this is the only study of patients treated with a combined subciliary and transantral approach. Special emphasis was given to postoperative functional results, a short algorithm for use of an additional transantral endoscopy-assisted approach is presented.

O.461 Reconstruction of severely atrophic jaws using calvarial bone grafts and endosseous dental implants

The purpose of this study was to test the mechanical capacities of 3 different bone grafting techniques in the atrophic maxilla when co-stabilized with dental implants. Reconstruction of the atrophic maxilla is a difficult clinical challenge and implants cannot be placed without adequate bone.The biomechanical performance of 3 different grafting techniques was evaluated in vitro using a maxillary model, cadaveric cranial bone blocks, and dental implants. A maxillary model fabricated from polyurethane (sawbone) was selected as a substrate for this study because of consistency in shape, size, and mechanical properties. This anatomic model was more consistent than different cadaveric maxilla, where significant variation was found to exist among atrophic specimens. Cadaveric cranial bone graft blocks were secured to the model maxilla (sandwich, ridge only, and sinus inlay) with a dental implant. The strength of the implant/bone graft complex was tested to failure in an Instron machine (Instron Inc, Canton, MA).The 3 bone grafting methods showed significantly different deformation and strength characteristics. The sandwich technique enhanced resistance to deformation under higher imposed loads. The location of the graft influenced the overall mechanical performance (eg, the ridge onlay) and showed a significantly higher resistance to compressive loads applied toward the alveolar ridge (mastication force).The ridge onlay grafting procedures created a higher biomechanical tolerance to imposed load than the sinus grafting (sinus inlay). Sinus grafting, although successful, was not the most ideal location for immediate mechanical loading resistance when compared with ridge augmentation in this in vitro model.

O.399 Cranial bone grafts for implant site development: Evaluation of donor site morbidity associated with the donor site

O.399 Cranial bone grafts for implant site development: Evaluation of donor site morbidity associated with the donor site

Prevention of Temporal Depression That Follows Fronto-orbital Advancement for Craniosynostosis

Contour abnormalities presenting after fronto-orbital advancement for craniosynostosis are common. Often there is bilateral temporal depression, the result of leaving a coronal bony gap posterior to the advanced segments. The authors present techniques to prevent this temporal depression by utilizing full-thickness bone grafts for structural support in the inferior coronal defects, and cortico-cancellous graft in the remaining superior coronal and parietal donor defects. Prior to contouring and repositioning the frontal elements, a hand-driven Hudson brace and D'Ericco bit is used to harvest cortico-cancellous bone "mush" from the endo- and ectocortical surfaces. The bandeau and frontal elements are advanced and secured, and the resultant coronal gap is measured. Full-thickness cranial bone grafts are harvested from the parietal regions (near the vertex) and secured in the coronal defect behind the frontal elements. The temporalis muscle is rotated, advanced, and secured to the bandeau. Bone mush is used to fill the remaining superior coronal and donor site defects. Representative case examples are presented.