Histometric analyses of cancellous and cortical interface in autogenous bone grafting.

Surgical procedures involving the rehabilitation of the maxillofacial region frequently require bone grafts; the aim of this research was to evaluate the interface between recipient and graft with cortical or cancellous contact. 6 adult beagle dogs with 15 kg weight were included in the study. Under general anesthesia, an 8 mm diameter block was obtained from parietal bone of each animal and was put on the frontal bone with a 12 mm 1.5 screws. Was used the lag screw technique from better contact between the recipient and graft. 3-week and 6-week euthanized period were chosen for histometric evaluation. Hematoxylin-eosin was used in a histologic routine technique and histomorphometry was realized with IMAGEJ software. T test was used for data analyses with p<0.05 for statistical significance. The result show some differences in descriptive histology but non statistical differences in the interface between cortical or cancellous bone at 3 or 6 week; as natural, after 6 week of surgery, bone integration was better and statistically superior to 3-week analyses. We conclude that integration of cortical or cancellous bone can be usefully without differences.

Biomechanical comparison of calcium phosphate cements for split cranial bone graft donor sites.

BACKGROUND: Although harvesting of in situ split cranial bone is a well-established technique, few data have been generated regarding the biomechanical effect of bone harvest on the cranial bone donor site, and even fewer data have been generated regarding the biomechanical effect of calcium phosphate bone cement inlay on the donor site. The authors documented the weakening of the skull at the in situ cranial harvest site and determined the benefit, if any, when the site is inlayed with calcium phosphate cements. METHODS: Cadaver skulls were divided into three groups: group 1, an in situ cranial bone defect was created in the frontal bone area on one side and the mirror-image, full-thickness area was untreated; group 2, a similar defect was created in the parietal area and repaired with calcium phosphate bone cement inlay, and on the opposite side, a similar defect was created but not repaired; and group 3, donor sites were created in the parietal area bilaterally and reconstructed with different cements. Mirror-image areas were harvested and testing was performed. The Wilcoxon rank sum test was used to evaluate all mirror-image specimens. RESULTS: There was a statistically significant difference in strength to fracture when the in situ defect was compared with the in situ calcium phosphate construct (p = 0.008). No difference was demonstrated when the defect was compared with full-thickness bone or when calcium phosphate cements were compared. CONCLUSION: Repair of the defect with calcium phosphate cement significantly increased strength at the donor site and may provide added safety from injury.

Reharvested cranial particulate bone graft ossifies inlay calvarial defects.

Particulate bone graft (PBG) heals calvarial critical-size defects and is procured from the cranium with a hand-driven bit and brace. The donor sites ossify, and thus PBG potentially could be reharvested from the original areas. The purpose of this study was to determine if PBG obtained from a healed donor site is effective for inlay cranioplasty. A 17 × 17-mm critical-size defect was created in the parietal bones of 8 rabbits and treated with either no implant (group 1) or PBG harvested from the frontal bone (group 2). In 4 animals (group 3), a parietal defect was not created initially; PBG was harvested from the frontal bone and then discarded. Sixteen weeks later after the PBG donor sites had healed, a 17 × 17-mm parietal defect was made and filled with PBG reharvested from the previous donor area. Animals underwent micro-computed tomography 16 weeks after inlay cranioplasty. Critical-size defects in controls (group 1) exhibited partial ossification (35.1% ± 10.5%) compared with those treated with PBG (group 2) (99.1% ± 1.5%) or reharvested PBG (group 3) (99.3% ± 1.5%) (P = 0.02). No difference was found between groups 2 and 3 (P = 0.69). Bony thickness was similar in defects implanted with PBG (1.8 mm ± 1.1 mm) or reharvested PBG (2.1 mm ± 0.5 mm) (P = 0.68). Particulate bone graft reharvested from healed donor sites ossifies inlay cranial defects. Because the donor area for PBG is of partial thickness and less than critical size, reparative osteogenesis theoretically allows an unlimited supply of autologous bone for inlay cranioplasty using PBG.

A novel technique for tailoring frontal osteoplastic flaps using the ENT magnetic navigation system.

CONCLUSION: The ENT magnetic navigation system is potentially useful and offers the most accurate technique for harvesting frontal osteoplastic flaps. It represents a valid tool in the wide range of instruments available to rhinologists. OBJECTIVE: Precise delineation of the boundaries of the frontal sinus is a crucial step when harvesting a frontal osteoplastic flap. We present a novel technique using the ENT magnetic navigation system. METHODS: Nineteen patients affected by different pathologies involving the frontal sinus underwent an osteoplastic flap procedure using the ENT magnetic navigation system between January 2009 and April 2011. RESULTS: The ENT magnetic navigation system was found to be a safe and accurate tool for delineating the frontal sinus boundaries. No intraoperative complications occurred during the osteoplastic procedures.

Long-term outcome of fibrous dysplasia: reconstruction with dysplastic bone--case report.

A 10-year-old girl presented with facial asymmetry associated with bulging of the right fronto-orbital region with no symptoms. Computed tomography demonstrated enlargement of the right zygomatic, frontal, ethmoid, and sphenoid bones. Abnormal proliferation of the bone had obliterated the sphenoid, right frontal sinus, and right ethmoid sinuses. These radiological findings suggested right optic nerve compression due to fibrous dysplasia. Right optic canal decompression was performed. In preparation for recurrence, the resulting bone defect in the right orbital roof was reconstructed using the outer table of the split lesion bone. The removed frontal bone was divided into intact and lesioned parts, and the intact part was returned. The lesioned part was split and the outer table graft used to reconstruct the frontal region. A temporal musculopericranial flap was used to form a barrier between the opened ethmoid sinus and cranial cavity. A protrusion appeared on the left forehead 10 years later, and was shaved to improve the aesthetic appearance. The patient was followed up for a total of 23 years. The use of dysplastic bone involves the risk of recurrence, but the period of recurrence is delayed and the progression stops after adolescence, so the second operation involved only shaving for aesthetic appearance. This procedure is one of the treatments of choice because of easy reconstruction, easy revision, and good results.

Autologous cranial particulate bone graft: an experimental study of onlay cranioplasty.

The purpose of this study was to determine whether particulate bone graft maintains its volume when used for onlay cranioplasty. Twenty-five adult, male, New Zealand white rabbits were divided into 5 groups (n = 5/group). Groups 1 to 3 were controls: group 1, untreated; group 2, sham procedure; and group 3, burring the cortical surface. Group s 4 and 5 had augmentation of the parietal bones with particulate graft harvested from the frontal bone with a brace and bit. The particulate graft was placed on native parietal bone (group 4) or on parietal bone that had been abraded to punctuate bleeding with an electric burr (group 5). Volume maintenance and osseointegration of the grafts were determined by micro-computed tomography and histology. At 16 weeks postoperatively, the mean (SD) volumes of the parietal bones in control groups 1, 2, and 3 were 555.8 (29.2), 550.8 (36.8), and 539.0 (39.0) mm, respectively. Immediately after cranioplasty, the mean (SD) volumes of augmented parietal bone were 846.0 (10.8) mm for group 4 and 831.8 (11.8) mm for group 5. Sixteen weeks postoperatively, 100% of the group 4 grafts had resorbed (551.8 [SD, 24.0] mm), and parietal volume was no different from controls (P = 0.89). Group 5 maintained 54.2% of volume (695.6 [SD, 22.0] mm), which was greater than those of the controls (P < 0.0001). Particulate graft may be used for onlay cranioplasty if the recipient site is burred. Approximately one half of the onlay graft is resorbed, and its original shape is not maintained.

What wrapped perichondrial and periosteal grafts offer as regenerators of new tissue.

The major goals in contour restoration procedures are to re-establish the desired contour with the use of resilient and durable materials that can be easily found and harvested. Cartilage grafts are commonly used for these purposes though they often possess a problem of donor site morbidity and shortage of quantity. The neo-cartilage formation capacities of both perichondrium and periosteum are well-known. We aimed to optimize both the amount and quality of the newly forming tissue from perichondrial and periosteal grafts. For this purpose the grafts were wrapped on themselves. Placement of oxidized regenerated cellulose (ORC) within graft layers was performed in two groups with the aim of giving support to the regenerating tissue, and increasing the connective tissue formation within the graft layers. Three-month-old New Zealand white rabbits were used. Group 1 ear perichondrial, and Group 2 calvarium periosteal grafts of 1.4 x 2.4 cm were harvested, folded on themselves, and sutured at the edges to create closed pockets. 0.8 x 0.8 cm sized ORC sheets were placed inside the pockets before wrapping in Group 3 perichondrial and Group 4 periosteal grafts. 0.2-mL autogenous blood was injected in each pocket. All grafts were transplanted under the abdominal muscle fascia, and harvested after 6 weeks. Volumes and weights of wrapped perichondrial grafts were higher than their periosteal counterparts either with or without the inclusion of ORC. Grafts with ORC (Groups 3 and 4) were heavier than the grafts lacking ORC (Groups 1 and 2), in a statistically significant manner (P

Experimental study of the frontal sinus development on Goettingen miniature pigs.

According to the literature, the development of the frontal sinus cavity is a result of the active immigration of cells from the ethmoidal complex into the os frontale. This migration theory is in contrast to the operative outcome of Apert's syndrome patients, after fronto-orbital advancement. When a fronto-orbital advancement at the age of a few months is performed in these patients while the frontal suture is yet closed, a sinus developed even the distance between nasal root and frontal bone bing up to 2 cm. In order to study the development of the frontal sinus, an animal study on 12 five-week-old infant Goettingen minipigs (GMP) was conducted, which did not have any clinical or histological signs of a frontal sinus development to investigate the development of the frontal sinus in "orthotopically" transplanted frontal bone with an open frontal suture. A comparison was made to a control group. The macro- and microscopical comparison with a control group revealed that the orthotopical transplants in the occipital bone developed epithelium-lined sinus, beginning from the thirty-fifth week. Based on these histomorphological results, a development scheme for the genesis of the sinus frontalis as a model were drawn.

Frontal periosteum as an exposed orbital implant cover.

PURPOSE: To describe the surgical technique of harvesting frontal bone periosteum, through an eyelid-crease incision, for coverage of orbital implants. METHODS: A retrospective review of the medical records of 15 patients who underwent the procedure. RESULTS: Eleven patients had surgery to cover exposed orbital implants, whereas in 4 patients the periosteal graft was used as an implant cover during enucleation. Periosteal grafts as large as 25 mm in diameter can be harvested. Recurrent exposure developed in 2 patients who had complicated histories of local trauma. One of these patients required a secondary dermis-fat graft, and the other experienced spontaneous granulation. The remaining 13 patients had excellent results without complications. CONCLUSION: Harvesting frontal bone periosteum, through an eyelid-crease incision, for orbital implant coverage is a relatively straightforward surgical technique. The procedure can be performed in the office under local anesthesia and yields excellent results. Recurrent exposure occurred only in 2 patients with histories of significant local trauma.

The galea frontalis myofascial flap in anterior fossa CSF leaks.

We report the clinical use of galea frontalis myofascial flaps in the treatment of anterior fossa cerebrospinal fluid leaks after trauma. This flap provides an adequately sized and vascularised barrier between the cranial and nasal cavities through which the cells of the inflammatory response reach the target area. This technique was used in 9 cases with complete success; in 5 out of 9 patients, repair of an anterior cranial base bone defect was also performed with split calvarial bone grafts, harvested from the frontal craniotomy bone. In all patients, neither recurrence of the CSF leakage nor postoperative meningitis or its recurrence were observed.

Controlled bending of cranial bone grafts: a simple surgical technique.

The cranium serves as a primary bone graft donor site in reconstructive craniofacial surgery. However, the mechanical properties of cranial bone predispose to fragmentation when excessive bending forces are applied, or to a return to the original shape when bending forces are insufficient. The precise and sustained contouring of cranial bone therefore remains a practical clinical problem. This paper describes a simple surgical technique which relies upon the application of a miniplate to the cortical surface of the cranial bone segment prior to bending. The miniplate serves to reinforce the segment, allowing accurate shaping of cranial bone and maintenance of the newly acquired contour.

Anterior table free bone graft technique for frontal sinus obliteration.

The osteoplastic flap technique for exposure of the frontal sinus has been an accepted approach for cases in which obliteration or exploration of the frontal sinus has been necessary. Preservation of vascularized anterior pericranium is credited with reduction of the chances of anterior table bone resorption and subsequent cosmetic deformity. Disadvantages include the need for templates and unpredictable random fracturing in the supraorbital rim area, increasing the chance of potential injury to the periorbita and/or supraorbital neurovascular structures as well as limiting surgical exposure in some cases. Ten patients with chronic frontal sinusitis underwent frontal sinus obliteration using an anterior table free bone graft technique over a 3 year period. The superior orbital neurovascular pedicles were easily identified and protected within its pericranial sheath in all cases. All patients had precise delineation of the frontal sinus anterior bone flap margins with no need for templates. Bone graft viability was documented in all patients, along with excellent cosmetic results comparable to the osteoplastic flap technique. A review of the literature and description of the technique are presented.

Tratamento de perdas de substancia ossea da regiao frontal com enxerto autogeno de tabua externa / Treatment of losses of bone substance of the frontal region with autogenic graft of outer table

Foram operados dez pacientes com perda de substancia na regiao frontal utilizando-se enxerto de tabua externa da regiao parietal, obtidos sem craniotomia. Em todos os casos foi restaurado o contorno da regiao frontal, sem sequela na area doadora. Os resultados avaliados clinica e radiologicamente mantiveram-se no acompanhamento de um ano. A utilizacao do enxerto de tabua externa da regiao parietal permite correcao dos defeitos da regiao frontal, com bons resultados esteticos. A morbidade na area e menor que na regiao da crista iliaca e ha menor reabsorcao ossea do enxerto.

[Treatment of losses of bone substance of the frontal region with outer table autogenic graft]. / Tratamento de perdas de substância óssea da região frontal com enxerto autógeno de tábua externa.

Ten patients with losses of frontal bone were operated with the use of bone grafts taken from the parietal area without craniotomy. In all patients the contour was restored without complications at the donor area. Results were evaluated clinically and radiologically one year later and no absorption was observed. We conclude that bone grafts from outer layer of parietal bone offer a satisfactory esthetic results. The morbidity at the donor area was not significant.

Split calvarial grafts in maxillofacial reconstruction.

Experience with thirty-seven patients demonstrating the versatility of the split calvarial graft in facial reconstruction is presented. A total of sixty grafts have been used with no evidence of significant clinical reabsorption, infection, or extrusion; advantages and limitations are discussed. We conclude that the split calvarium represents a readily available and reliable source of membraneous bone for grafting maxillofacial defects with minimal limitations and low morbidity.

Further application of supratrochlear vessels to facial repair.

We performed transplantations of cranial bone and scalp using the supratrochlear vessels as a pedicle. We confirmed that these vessels could be used for moving the tissues between the eyebrow and the coronal suture.

Vascularized calvarial flaps.

Vascularized calvarial transfers offer many advantages. In this article the anatomic (soft tissue, vascular, osseous) basis of flap design is summarized, and the technical details of two calvarial flaps, the temporoparietal and the frontoparietal, are presented.

Giant osteoma of the sphenoid sinus reached by an extradural transbasal approach: case report.

Giant osteomas of the paranasal sinuses are infrequent. Those of the sphenoid sinus with neurological symptoms are even rarer. We report here the case of a woman with a giant osteoma of the sphenoid sinus who presented with bitemporal quadrantanopsia and underwent operation via an extradural transbasal approach.

Comparison of residual osseous mass between vascularized and nonvascularized onlay bone transfers.

Composite flaps containing vascularized frontal bone were transferred on muscle pedicles in immature rabbits. Vascular continuity was maintained on one side and interrupted on the other. Bone weights at 16 weeks following transfer were compared with those of unoperated controls. The conventional bone graft demonstrated significant reduction in osseous mass. The vascularized bone maintained its mass compared with unoperated controls. Vascularized bone transfer appears to be the preferred surgical technique whenever possible.