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Objective: Topographic and blood vessel architecture study of the parietal area and distal regional pool of the superficial temporal artery (STA) to assess the possibility of revascularized cranium vault bone autograft formation., Material and Methods: For the topographic and anatomical study, 30 non-fixed corpses (17 male and 13 female) were selected, the average age of which was 59±5 years. In the anamnesis and catamnesis, there were no indications of trauma or other pathology of the head and neck, including vascular. STA was contrasted with a non-radiocontrast dye (brilliant green) with the introduction of the dye into the STA with preliminary ligation of the frontal branch of the STA. The area of blood supply to soft tissue and bone structures was studied. The angioarchitectonics of the parietal region was studied, the feeding vessel of the studied flap was identified., Results: The obtained anatomical landmarks for the collection of CPFP flap make it possible to form a flap with high accuracy and minimize the morbidity of the donor area.

The aim of the present study was to evaluate the effects of systemic EPO treatment alone or in combination with xenogenic bone graft augmentation on bone regeneration. Eleven adult male Sprague-Dawley rats were used in the present study. Rats were subjected to bilateral 5 mm critical size bone defects on the parietal bones under general anaesthesia. Right parietal bone defects were augmented with xenogenic bone graft and left parietal bone defect was left empty. Rats were randomly assigned for one of the two groups. One group of rats received (i) vehicle (n = 6) and other group received (ii) EPO (500IU kg/day) (n = 5). EPO treatment was continued for 28 days. Vascularization was analysed by immunohistochemical staining of CD31 (PECAM-1) and new bone formation was histomorphometrically evaluated. Xenogenic graft augmentation enhanced bone formation and vascularization significantly in either vehicle or EPO treated groups (p < 0.05). Histomorphometric results of angiogenesis was similar in the EPO treated group and the control group. However, angiogenesis was significantly higher in the combination of systemic EPO treatment with graft augmentation than graft augmentation alone (p < 0.01). Graft augmentation for treatment of critical size bone defects seems essential for proper bone healing. Results of the present study suggest that EPO potentiates the regenerative processes of augmented bone defects., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: Surgical skills can be improved through practical exercise. The use of specimens, human as well as animal, or live animals for surgical training is limited due to ethical concerns. Drawbacks of simulators are costs, fidelity and creditibility. Thus, simulators must be evaluated objectively to determine their validity before they can be used as teaching modalities. The aim of this study was to verify the face content and construct validity of a novel model-based simulator for lifting tabula externa transplants from the parietal skull., Materials and Methods: Participants were invited to perform a tabula externa graft lift during a training session on the simulator. Task performance was analyzed with a standardized assessment tool evaluating realism and appropriateness. Specialist ratings were used to evaluate the performance of the participants. This was an exploratory study using a questionnaire, at Kepler University Hospital, Linz, Austria, a university hospital. According to their expertise in craniomaxillofacial surgery, 17 participants were subdivided into 3 groups: 8 novices, 7 experts and 2 raters., Results: The face validity (realism) obtained an average score of 4.2 of a maximum of 5 points. Likewise, the content validity (appropriateness as a teaching modality) obtained an average score of 4.8 of maximum 5 points. No differences were found between experts and novices concerning the recorded surgery completion times (p = 0.418) or the sizes of the lifted grafts (p = 0.110). During the evaluation of task performance, the expert surgeons (46.9 ± 3.7) were graded significantly better than the novices (36.4 ± 8.5), which proved the construct validity of the simulator (p = 0.001)., Conclusion: All investigated validities were confirmed and approved the simulator as a valid training tool for parietal graft lift., (Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: Parietal bone grafts are commonly used in cranio-maxillo-facial surgery. Both the outer and the internal layer of the calvarium can be harvested. The bone defect created by this harvesting may induce significant weakening of the skull that has not been extensively evaluated. Our aim was to evaluate the consequences of parietal bone graft harvesting on mechanical properties of the skull using a finite element analysis., Methods: Finite elements models of the skull of 3 adult patients were created from CT scans. Parietal external and internal layer harvest models were created. Frontal, lateral, and parietal loading were modeled and von Mises stress distributions were compared., Results: The maximal von Mises stress was higher for models of bone harvesting, both on the whole skull and at the harvested site. Maximal von Mises stress was even higher for models with internal layer defect., Conclusions: Harvesting parietal bone modifies the skull's mechanical strength and can increase the risk of skull fracture, mainly on the harvested site. Outer layer parietal graft harvesting is indicated. Graft harvesting located in the upper part of the parietal bone, close to the sagittal suture and with smooth internal edges and corners should limit the risk of fracture., (Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: For a century, autologous bone grafts have been used in maxillofacial reconstruction. The ideal bone harvest site and grafting procedure remains a point of contention in regards to obtaining optimal long-term results with sufficient bone quantity and density without serious complications. More recently, confronted with growing patient requests and biomaterials development, maxillofacial surgeons and dentists have been considering these issues as they relate to pre-implant surgery. This study sought to evaluate implant success rate and complications following pre-implant surgery with parietal bone grafting., Materials and Methods: A retrospective study was carried out on patients who underwent maxillofacial reconstruction of different sites (symphysis, mandibular corpus, maxillary sinus and premaxilla) for the purpose of implant insertion., Results: 311 procedures in 211 patients were included. The implant osseointegration rate was around 95%. Clinical follow-up ranged from 10 months to 11 years. A secondary procedure was performed in 6.1% of cases and we noted no serious complications at the harvest site., Discussion: With good revascularization and osseointegration of the graft, the use of parietal bone leads to an implant success rate similar to that seen in the literature. Moreover, the use of this material results in few infections and low bone resorption provided there is strict immobilization of the graft and no tension on the soft tissue sutures., Conclusion: Parietal bone grafts technique possess the required qualities for the success of implant surgery, offering results at least as interesting as others using autogenous bone and with no serious complications on donor site., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: Long standing maxillary edentulism leads to alveolar ridge resorption which prevent implant placement and causes prosthetic malocclusion. The aim of the study was to assess vertical and transversal bone increase following Le Fort 1 osteotomy associated with calvarial bone grafting., Materials and Methods: 66 patients who presented severely atrophic maxillae were treated with Le Fort 1 osteotomy with bone grafting from 2003 to 2014. Vertical and transversal bone level was measured preoperatively and 6 months post-operatively to calculate the alveolar ridge augmentation. Follow up ranged from 10 months to 11 years., Results: The mean increase of bone height was 9.3 mm and the mean increase of bone width was 6 mm 417 endosseous implants were placed in the grafted maxilla. Mean endosseous implant length was of 10.7 mm at the first molar site (range: 8-16 mm). A total of 25 implants failed, the overall implant survival rate is of 94%. The definitive prosthetis was fixed in 65% of the patients and removable in 35% of the patients., Discussion: Le Fort 1 osteotomy associated with calvarial bone grafting is the main treatment option able to offer fixed bridge and perfect class 1 occlusion in cases of severe maxillary atrophy., (Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose of the Study: Posttraumatic enophthalmos cause complex cosmetic problems to fix. In order to get better results, we wanted to calculate the volume of parietal bone graft needed to be put in place, know where to place it in orbit and study soft tissues' participation., Patients and Method: In a retrospective study, we have calculated on scanner the volume of bone and soft tissue as well as the volume and the location of the graft. We have compared, between two groups ("good result" and "insufficient result"), graft volumes, taking into account differences in bone's volume between the healthy and the traumatized orbit. A comparison of the locations of the graft was also made. We were trying to find out if these factors were involved in the quality of the result., Results: Twenty-nine surgeries on 24 patients were analyzed. The average bone's volume of an orbit with enophthalmos was 24.76 cm(3) for 17.12 cm(3) of soft tissue. Retro-lens distance was the most reliable measurement method of enophthalmos (P=0.001). There was a trend to a more substantial over-correction in the group "good result". A significant increase (P=0.0008) of soft tissue volumes in the traumatized orbit was found., Conclusion: This last result is surprising. Many authors believe that there is a scar retraction of soft tissues. But Kronish et al. showed an increase of the fat density and connective tissue. This, together with the assumption of a weathering of the ligament suspension of the globe, may affect our aesthetic results. MRI, ultrasound and anatomopathological studies would allow a better understanding of the fat, muscle and ligament pathophysiologies of an orbit with enophthalmos., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Background: The purpose of this study was to develop a bone tissue bank using a programmed freezer with a magnetic field. Parietal bones were removed from rats and used for organ culture examination (non-cryopreserved, cryopreserved with a magnetic field (CAS) and cryopreserved without a magnetic field group). Next, other parietal bones were used for histological examination. The cryopreserved bones by a CAS freezer and dried bones were transplanted respectively. Control bones were replanted without cryopreservation. Animals were sacrificed at 4, 8, 12 and 24 weeks after surgery. After organ culture, the isolated osteoblasts from parietal bones which were cryopreserved by a CAS freezer can survive and proliferate as much as non-cryopreserved group. Histological examinations showed new bone formation in control and CAS group. These results suggest that bone tissue cryopreservation by CAS freezer can be successfully used for bone grafting which may be a novel option for regeneration medicine.

Despite increasing advances in endonasal frontal sinus surgery, frontal sinus obliteration (FSO) is sometimes necessary after failure of other surgical techniques. This procedure has been reported with autologous tissue or synthetic material, but few studies have reported results with autologous calvarial bone graft. The aim of this study was to report our experience with osteoplastic FSO calvarial bone graft. A retrospective review was performed on 11 patients operated upon for FSO with autologous calvarial bone graft from 2005 to 2011. Obliteration was indicated for chronic symptomatic frontal sinusitis with nasofrontal duct stenosis in five cases of nasal polyposis with a history of endoscopic sinus surgery, two cases of frontal trauma, two of surgery for frontal inverted papilloma and two of chronic frontal purulent sinusitis. Ten patients had a history of one or two previous functional endoscopic sinus surgery (FESS) procedures. On outcome assessment, eight patients had no residual complaints after FSO and all patients showed improvement in symptoms. Frontal sinus obliteration with autologous calvarial bone graft showed low donor site morbidity and good aesthetic results. This procedure should be considered in severe frontal sinusitis after repeated FESS procedures have failed.

Background: Autologous bone grafts are usually well consolidated after 4 to 5 months but can be incompletely interlocked with the native bone. This study investigated the effect of acid demineralization of the graft-bed interface on graft consolidation., Methods: Onlay bone grafts were performed on the calvaria of 36 guinea pigs. Half of the animals had the graft-bed contacting surfaces demineralized with 50% citric acid (pH 1.0) for 3 minutes (test group). The other half received no demineralization (control group). The bone grafts were immobilized by a resorbable membrane glued to the recipient bed with cyanoacrylate. After 7, 30, and 90 days, specimens (n = 6) were obtained for light microscopy. Data from qualitative analysis and computerized histomorphometry were statistically processed at a significance level of 5%., Results: Osteogenesis was not seen at the interface after 7 days. After 30 days, the test group showed 34.39% ± 13.4% of the interface area filled with mineralized tissue, compared to 17.14% ± 8.6% in the control group (P = 0.026). After 90 days, the mean percentages of mineralized tissue at the interface in the test and control specimens were 54.00% ± 11.23% and 38.65% ± 7.76% (P = 0.041), respectively. Within groups, a higher percentage of the area filled with mineralized tissue was seen at 90 days compared to 30 days (P = 0.004 for control and 0.041 for test)., Conclusions: Demineralization of the contacting surfaces between autologous bone graft and bone bed improved new bone formation and bone consolidation. These data need to be confirmed in humans.

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.

Introduction: Decompressive craniectomy is an alternative in cases where there is increased intracranial pressure. Bone autografts are accepted as a method of reconstruction of the skull. The aim of this paper is to describe the macroscopic and radiological findings of autologous parietal bone in rats after storage in adipose tissue as a reservoir., Methods: We used 20 Wistar rats which underwent a craniectomy. 4 groups were formed: group I, the bone flap fat remained for 14 days, group II, the flap remained for 21 days, in group III, for 28 days and in group IV for 35 days. They were euthanized 70 days after reattached., Results: When removing the flap of subcutaneous fat, a high bright whitish microvasculature and presence in 11 of the flaps. Following 70 days of re-injertarse was found that 56.25% of the animals presented terraced edges, reflecting some consolidation in the radiological analysis 31.25% of cases showed areas of consolidation. Animals in group II and III findings showed more consolidation., Conclusions: The bone flap remained viable during their stay in adipose tissue. Fibrous tissue and neovasculature were important findings that reflect the proper process of bone healing. You need the histological studies complemented biomechanics, neurological and bioacoustics.

Variable resorption occurs whenever calvarial bone graft is used for onlay cranioplasty. The recipient ectocortex may be burred to expose vessels and osteocytes to maximize healing. The purpose of this study was to determine whether abrading the recipient site improves the volume of onlay graft. The parietal bones of 17 rabbits were sectioned into split-thickness and full-thickness grafts. The right frontal cortex was abraded with a bur to punctate bleeding. Pairs of split-thickness (n = 48) or full-thickness (n = 20) grafts were onlayed to the burred right frontal bone and to the nonburred left frontal bone. Micro-computed tomography was used to determine graft volume immediately postoperatively and 16 weeks later. Histology, including tartrate-resistant acid phosphatase staining, was performed to quantify vascular channels and osteoclasts per high-power field 10 days postoperatively. Split-thickness graft volume decreased 58.0% when placed on the burred calvarial site, compared with grafts on the nonburred cortex (28.4%) (P = 0.01). Full-thickness grafts showed a similar trend: greater resorption (39.1%) when onlayed onto abraded calvaria compared with nonburred ectocortex (26.0%) (P = 0.11). Split-thickness graft orientation (cortical vs cancellous side in contact with the recipient site) did not affect resorption (P = 0.67). Onlay grafts placed on the burred recipient site had more vascular channels (11.8) and osteoclasts (5.7), compared with grafts over nonabraded cortex (3.4 and 4.2, respectively) (P < 0.05). Burring the recipient site cortex before onlay cranial bone grafting promotes resorption, possibly by increasing vascularization and osteoclastic activity. This technique cannot be recommended.

Parietal bone grafts are commonly used in craniomaxillofacial surgery. However, bone removal may weaken the parietal bone and lead to deleterious complications. The aim of our study was to design a test protocol for characterization of the impact resistance of parietal bone before and after monocortical bone graft harvest and to validate an optoelectronic measurement of parietal bone thickness. Twelve fresh human cadaver heads were used for the validation study. To evaluate impact resistance, we developed a pendulum Charpy impact testing machine. The impact force was gradually increased until failure (fracture) of the defined parietal bone area. According to the protocol, we measured the maximum absorbable energy or impact force to failure. With our test setup, measurement of the impact resistance of parietal bone was accurate to within 0.025 J. We defined a range of values and particularly a threshold value. The initial maximal impact must not to exceed 4 J. For more accuracy, we compared 5 nondestructive measurement methods using a surgical navigation system with optoelectronic tracking. We achieved an algorithm based on 2 methods that ensured a measurement resolution of 0.1 mm. Validation of this protocol will allow us to evaluate the loss of strength resulting from bone removal and the correlation between strength and thickness of the parietal bone.

Background: Parietal bone grafts are commonly used in craniomaxillofacial surgery. The primary aim of this study was to quantify the loss of strength following monocortical parietal bone graft harvest. The secondary aim was to establish a correlation between strength and thickness of calvaria., Methods: Thirty fresh human cadaver heads (nonfrozen, unembalmed heads) were used for this study. Loss of strength was determined by comparing the maximum impact resistance of bone on the donor side versus the intact side, using a precalibrated pendulum Charpy impact testing machine. Thickness was measured using a surgical navigation system with optoelectronic tracking., Results: Loss of strength at the donor site was 36 percent (p=0.0000000001) for a 40 percent loss of thickness. Although correlation between these two parameters is rather moderate (r=0.46), it is highly significant (p<0.0001)., Conclusions: Although loss of strength is quite significant, serious complications at the donor site are rare. As shown in this study, these risks are nonnegligible. However, because of strong legal pressure, surgeons must carefully weigh the risks incurred by the patient against the expected benefits, whether immediate or deferred. Therefore, the patient should receive well-documented information before such monocortical parietal bone graft harvest is performed.

Cranioplasty is a well-established reconstructive procedure for restoring craniocerebral protection and improving cosmetic defects. Most allograft materials are not suitable in pediatric patients owing to skull growth; thus, autologous bone is often preferred in the reconstruction of the pediatric skull because of its capacity to osseointegrate and grow with the pediatric skeleton. A 33-month-old boy with Ewing sarcoma of the right frontal bone underwent surgical treatment with tumor excision. The resected bone was reconstructed with full-thickness calvaria harvested from the right parietal region. The residual parietal gap was filled with homologous bone taken from the iliac wing. This reconstructive technique was chosen to guarantee normal development of the frontal region and tissue integration, while considering possible radiotherapy after the primary surgery., (Copyright 2010 Elsevier Inc. All rights reserved.)

Bone regeneration procedures allow oral rehabilitation with dental implants also in edentulous ridges with severe bone atrophy. The integration of grafted materials with the host tissue can initiate regenerative, inflammatory and apoptotic response. Since molecular mechanisms exist at the basis of such response, the aim of this work is to investigate, by immunohistochemical analyses, the expression of proteins involved in the graft integration process, in parallel to clinical and histological modifications, occurring on sites treated with extraoral autologous bone graft deriving from the parietal region of the calvaria (eAB), intraoral autologous bone graft deriving from mandibular ramus (iAB) and heterologous bone graft from swine (hB) in human patients. In our study, the immunohistochemical expression of BSP, VEGF, eNOS in eAB samples was significantly higher (p < 0.05) compared to values recorded in iAB and hB samples. The inflammatory response, investigated by iNOS expression, was found lower in all autologous samples (eAB and iAB) compared to hB, at statistically significant values. Moreover, the expression of the pro-apoptotic molecule, Bax, resulted significantly lower (p < 0.05) in eAB than in iAB and hB samples. These values, together with the low number of apoptotic cells detected in autologous samples, suggest a good regenerative response when extraoral autologous bone graft is used in comparison to the response from the other grafts, and also suggest the use of calvaria graft as a predictable therapeutic procedure for repairing severe bone defects in oral and maxillofacial surgery, not only by clinical and biomechanical criteria, but also from a biomolecular aspect.

Isolated sagittal synostosis is a common form of craniosynostosis affecting roughly 1 in 5,000 children at birth. This results in a scaphocephalic head shape with a characteristically elongated anterior-posterior dimension and narrowed biparietal diameter. We present our experience with the correction of scaphocephaly due to sagittal synostosis using cranial vault reconstruction with a novel form of parietal bone fixation in 21 patients over 10 years. The medial fixation results in a hinging effect whereby transverse brain growth at the squamoid suture is enhanced. This results in excellent cosmetic results that are immediate and durable without the need for postoperative molding helmets. Furthermore, the complications associated with this procedure are limited., (Copyright (c) 2007 S. Karger AG, Basel.)

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.

Midfacial reconstruction after radical oncological resection is a challenging endeavor and several options can be employed: prosthethic devices, pedicled flaps (with or without the aid of autologous or alloplastic grafts), and microvascular flaps. Each technique has specific indications, advantages and disadvantages. The use of traditional surgical reconstructive procedures seems to be shifted nowadays by microvascular free flaps. Nevertheless, in our experience the myofascial temporalis flap associated with free calvarial bone grafts demonstrate to be a safe and versatile option in primary midfacial reconstruction. From this point of view the authors have developed a technique for one-stage reconstruction of the orbito-maxillary skeleton and soft tissues and without the use of microsurgical flaps; this surgical procedure can be used only on patients for whom a resection of the cutaneous tissues and exenteratio orbitae are not necessary. The aims of this paper is to describe the surgical technique and to show a retrospective analysis on 17 patients which underwent midfacial radical resection and immediate reconstruction with calvarial bone grafts and temporalis muscle flap along 15 years.

Purpose: To report the use of autologous pericranium grafts to cover exposed orbital implants., Methods: A two-center consecutive case series of exposed orbital implants covered with autologous pericranium grafts. A patch of pericranium was harvested from the parieto-occipital region and was placed over the implant within a pocket between the implant and the Tenon capsule, followed by layered closure of Tenon and conjunctiva., Results: Four patients (2 women, 2 men) with a mean age of 37 years (range, 26 to 45 years) were included in the study. The mean follow-up period was 9.5 months (range, 7 to 12 months). In all cases, there was no recurrence of exposure and no donor site morbidity. A small pyogenic granuloma, arising from the conjunctival suture line, developed in one case., Conclusions: Autologous pericranium is a useful covering material for exposed orbital implants and may be used as an alternative to frontal periosteum.

Particulate parietal bone is used for maxillary sinus floor elevation procedure prior to dental implant placement. However, data on internal structure of the parietal bone and on graft remodeling and incorporation in the host bone are limited. We determined the structure and remodeling activities of 24 parietal bone specimens sampled at time of sinus grafting (T1 samples), and the amount and turnover of bone formed at the recipient site at time of implant placement (T2 samples, obtained 10 months after T1 samples, on average). In T1 samples, the outer cortex was 1.16+/-0.45 mm thick, had a typical haversian structure, and showed a low level of remodeling. In the cancellous portion of the samples, trabecular bone volume represented 52.8+/-10.3%. Bone remodeling was more active in the cancellous portion than in the cortical portion, but few osteoblasts and osteoclasts were seen. T2 samples consisted solely of trabecular bone, which occupied 49.4+/-18.4% of total sample volume. The boundary between new bone and the recipient bed was not discernible. Remnants of the graft particles were embedded within new bone, and showed signs of intense resorption. Bone remodeling was highly active, as shown by the presence of numerous osteoclasts resorbing new bone, together with thick osteoid seams and large osteoblasts. A loose cotton-like mineralized material was frequently observed in the marrow spaces; this acellular and non-collagenous material was strongly stained by toluidine blue, suggesting a glycoprotein nature. This study offers insights into cortical and trabecular bone structure and shows the low-level remodeling activity of parietal bone. About 10 months after grafting, the grafted chips were incorporated in new bone and almost completely resorbed. This high turnover may be beneficial for implant placement.

Bone wax was used to stop bleeding of the diploic vessels after harvesting cranial bone for reconstruction of an orbital floor defect. After five months a fistula in the overlying skin of the donor site appeared and was eventually surgically explored. Remnants of bone wax and surrounding inflammatory tissue were removed and the fistula was excised. Histological examination revealed a foreign body granuloma. The use of bone wax and possible alternative local haemostatic agents and their complications are discussed.

To clarify the clinical utility of the parietal bone graft in maxillofacial reconstruction, we performed an anatomical study by measuring the regional thickness of the parietal bone in 47 Korean adult dry skulls. Before sectioning of the calvaria, the appropriate anatomical landmarks were marked on each specimen. We measured the total thickness of the parietal bone, and the thickness of the outer and inner cortical plates at various points in each section of parietal bones using a digital caliper under the stereomicroscope. The total thickness of the parietal bone ranged from 5.04mm to 7.17mm, and there was no statistical difference in the total thickness of the parietal bone on the same points bilaterally. The parietal bone tended to be thicker toward the lambda point than at the coronal suture area. On the other hand, the outer plate of parietal bone was thickest at the point nearest to the coronal suture, and the inner plate proved thickest at the posteromedial area. In conclusion, this study showed that the better donor site of the parietal bone for maxillofacial reconstruction is located at its more posterior and medial area.

Recent advances in bioabsorbable devices have introduced tacks that do not require tapping. This may help to reduce operative time and, consequently, costs. The goal of this study was to demonstrate the feasibility of a new method of cranial bone osteofixation using novel bioabsorbable tacks and plates instead of screws. A 36-year-old man presented for elective cranioplasty to reconstruct a large frontal cranial bone defect that followed a decompression operation performed because of a head injury sustained 6 months previously. Cranioplasty was performed using split parietal bone grafts to reconstruct the defect. Bone grafts were fixed together and to the skull using self-reinforced (SR) poly(L/DL)lactide [SR-poly(L/DL)lactide] (70/30) (Biosorb FX) plates (n = 10) and tacks (n = 98). The plates were 0.6 mm thick, 102 mm long, and 12 mm wide. The tacks had a maximum thread diameter of 2 mm and a length of 6 mm. The tacks used did not require any tapping procedure, and they were applied using a special applicator gun. Stable and secure fixation was obtained during surgery. The postoperative period was uneventful, except for delayed epithelialization of a small area (1 x 0.5 cm) over the frontal skin that healed later. One year after surgery, the cosmetic result was excellent, and no complications were detected. Stabilization of large cranial bone pieces can be achieved using bioabsorbable SR-poly(L/DL)lactide plates and tacks, with excellent cosmetic results. The method is thought to be reliable and may help to reduce operative time.

Orbital and intracranial complications of dental cellulitis are exceptional. The authors report such a case with orbital cellulitis and frontal abscess that dictated orbital exenteration with resection of the eyelids. Before realization of an implant supported epithesis, the orbit was filled with a prefabricated vascularized fascio-osseous parietal bone flap. This allowed placement of two extra-oral fixtures (Nobel biocare) in an antero-posterior axis. In some cases, preimplant orbital bone graft appears to be the only solution when implant placement in the orbital rim is impossible or contra-indicated. Indications, advantages and disadvantages of this technique will be discussed.

Histomorphological studies carried out during 1 month after autotransplantation of the parietal bone into a facial skull defect showed necrosis of osteocytes, contents of bone marrow spaces, and feeding channels in the transplanted autobone. During this period and later loose connective tissue grows into them. As a result of resorption of osseous matter, new bone cavities are formed and the lumina of feeding channels are dilated. Simultaneously a new bone substance, containing viable osteocytes, appears on their walls. Gradually the autobone graft is replaced by newly formed bone tissue.

Temporoparietal fascia constitutes a very important structural unit from both an aesthetic and a reconstructive surgical point of view. A histologically supported anatomic study was conducted for the reappraisal of the anatomic relationships and clinical application potentials of the data obtained. Anatomy of the temporoparietal fascia was investigated on 20 sides from 10 cadavers. After dissections, necropsies were obtained to demonstrate histologic features of the temporoparietal fascia. The outer part of the temporoparietal fascia is continuous with the superficial musculoaponeurotic system (SMAS) in the inferior border and with orbicularis oculi and frontalis muscles in the anterior border. Therefore, plication of the temporoparietal fascia can increase tightness of the SMAS, orbicularis oculi, and frontalis muscle in rhytidectomy. The frontal branches of facial nerve were noted to course parallel to the frontal branch of the superficial temporal artery, lying deeper to the temporoparietal fascia within the innominate fascia. In the view of these findings, conventional subfascial dissection, which is performed to protect frontal branches of the facial nerve, is not reasonable during the temporal part of rhytidectomy. Careful subcutaneous dissection just under the hair follicles is more appropriate to avoid nerve injury and also provides excellent exposure of the temporoparietal fascia for plication in rhytidectomy with protection of the auriculotemporal nerve and the superficial temporal vessels. Furthermore, two layered structures of the temporoparietal fascia are very suitable to insert a framework into the temporoparietal fascia for ear reconstruction to eliminate some of the shortcomings of Brent's technique. A thin muscle layer was also noted within the outer part of the temporoparietal fascia below the temporal line; the term "temporoparietal myofascial flap" would, therefore, be more accurate than "temporoparietal fascial flap." Finally, the innominate fascia and the deep temporal fascia can be elevated with the two layers of the temporoparietal myofascial flap to obtain a well-vascularized, four-layered myofascial flap based on the superficial temporal vessels. This multilayered flap can be used to reconstruct all defects when fine, pliable, thin, multilayered flaps are required.

Many calvarial bone defects are still being repaired using non-biological materials such as titanium when a patient's own bone can provide an alternative with all the immediate and long-term biological advantages (and resource benefits) that come with using autologous tissues.

Twenty-seven nasal reconstructions with parietal bone graft performed between January 1989 and January 1995 were analyzed retrospectively. No complications involving parietal bone were observed. After a 2-year follow-up there have been no cases of shifting, extrusion or resorption of the rhinoplasty. Our experience shows that calvarial bone is an ideal material for nasal reconstruction bone grafts.

Replantation of resected bone after autoclaving is employed by many units in both craniofacial and orthopedic tumor reconstructive surgery. The procedure is attractive because it maintains the original anatomy, is reliable, and provides a good immediate clinical result. However, doubts have been raised about the ability of the autoclaved bone to revitalize. The present study aimed to explore, in an animal model, the revitalization of autoclaved bone and to determine whether it would be possible to enhance graft revitalization using either autogeneic bone marrow or recombinant human fibroblast growth factor-2, a peptide with stimulatory effects on both endothelial and osteogenic cells. Twenty-eight adult rats were subjected to bilateral parietal cranioplasties (4 x 6 mm), and 75 percent of the grafts were subjected to autoclaving (121 degrees C; 20 minutes) and subsequently treated randomly according to one of the following strategies: no further treatment, or supplementation with bone marrow or recombinant human fibroblast growth factor-2. The remaining grafts were replanted as fresh autografts. The results were evaluated after 4 and 12 weeks by radiologic, histologic, and histomorphometric analyses. After 4 weeks, no major differences were observed between treatments. At 12 weeks, however, no distinction in graft revitalization between autografts and autoclaved grafts supplemented with recombinant human fibroblast growth factor-2 was observed, whereas autoclaved grafts with or without bone marrow displayed significantly less revitalization compared with autografts. The results indicate that autoclaved bone will revitalize by remodeling, and that the efficacy of this process can be increased significantly by simultaneous supplementation with recombinant human fibroblast growth factor-2.

Between years 1996 and 1997, pedunculated parietal bone graft for facial reconstruction after tumor excision was used in 8 patients. The defects comprised one side of maxilla with the orbit bottom, zygomatic bone and the orbit bottom, mandibular ramus, and the whole mandible: in 4, 1, 2, and 1 patient respectively. The reconstruction was done directly after tumor excision in 6 patients and later on in the other 2. The grafts were of full thickness in 6 and of outer table in 2. Functional and cosmetic effects were considered satisfactory in 6 patients. The whole mandible reconstruction ended up with a failure due to infection and tumor recurrence.

Sixteen patients (mean age, 1.9 years) underwent split-thickness calvarial bone grafting using a full-thickness craniotomy, high-speed drill, and osteotomes for bone harvesting. The minimal calvarial bone thickness for a successful graft was found to be 7 mm. All patients were diagnostically studied preoperatively with computed tomographic scans and skull films. The mean follow-up was 2.9 years (range, 0.75-7.9 years). All patients had successful graft take. There were no infections or mortalities. Continued graft growth was seen in all patients. There was one dural tear during harvesting with no cerebrospinal fluid leak or postoperative sequelae. This analysis indicates that split-thickness calvarial grafts can be safely and adequately performed in children as young as 13 months of age.

Over the last two decades, the concepts of cosmetic rhinoplasty have advanced, essentially due to the influence of J. Sheen. The importance of the anatomy of osteocartilaginous structures, their dynamic role, and the repercussions of their modification on the external shape has led to a more conservative surgery. Innovations have essentially concerned nose tip surgery and cartilage grafts. The revival of external approach and its popularity constituted the second major development; this can be explained by the direct, visualisation of cartilaginous structures and by the desire or necessity to preserve or reconstruct these structures. The indications for cartilage grafts have become more frequent and graft techniques have been developed and refined. The difficulties encountered in the use of autologous grafts have favoured the development of many new implants. Parietal cranial grafts occupy an increasingly important place in the indications for nasal bone grafts.

Autologous bone grafting of alveolar clefts is a well recognized procedure. Calvarium represents an interesting donor site because of the absence of morbidity and the dimensional stability of this membranous bone compared with endochondral bone sources. The authors reponed their experiences with this type of grafting used in 17 patients. Referred to the parameters analized in an important Swedish study, the rate of success was about 80% agree with the results of other authors with the same type of graft. Aspects of general planning, timing, technique and failure are extensively discussed. Pre and post surgical orthodontic treatment is also very important for a good result. The pattern of maxillo-facial growth and the effect of the graft materials on facial development are mentioned. The study of literature indicates that the best grafting results are achieved when free autogenous mandibular symphyseal bone grafts were used. The only true disadvantage is the small quantity of bone tissue available. The authors conclude suggesting the use of chin bone grafting in situations where the technique provides sufficient bone and recommend the use of cranial vault as the alternative source of membranous bone graft, for example, in bilateral clefts, when anterior theeth are not erupted yet and in any other situation where the mandibular bone graft is not possible.

The embryologic origin of the parietal bone is membranous bone. Experimentally, membranous bone grafts, maintain its original size, structure with good osteo-integration contrary to endochondral bone autografted (ilium, rib or tibia). The morbidity of skull bone grafts is much less than other donor site of bone. In our study, between 1988 and 1992, autogenous split calvarial bone grafts were used in maxillo-facial reconstruction of seventy-one patients. We observed no major complication. Patient followup has been from 2 to 6 years and results are better than endochondral grafts (iliac crest, ribs, tibia). Parietal grafts bone have been used in the following case: nasal reconstruction, rehabilitation of defects in the floor of the orbit, maxilla grafts, correction of frontal depression and mandibular reconstruction.

Since 1990, fresh autogenous split skull cranioplasty has been the preferred method of reconstructing complicated cranial defects at the Sunnybrook Hospital. Eight cases of split skull cranioplasties were reviewed to illustrate the indications and technical considerations of the procedure. Clinical factors believed to be detrimental to the outcome of split skull cranioplasty were identified by: 1) a history of an infected, failed, previous cranial reconstruction, 2) inadequate scalp or skin to cover the external surface of an anticipated skeletal vault reconstruction, 3) the communication of adjacent paranasal sinuses with the epidural space, 4) the presence of an avascular dead space posterior to the reconstructed cranium. These potentially negative influences were systematically addressed as part of the surgical routine in autogenous split skull cranioplasty.

Popularized by Tessier in 1982, the calvarial bone graft has been used extensively in reconstructive techniques in the cranio-facial region. The authors present here their experience of nasal bone grafting using split skull grafts for post-traumatic reconstructions. Ten patients, with a total of 11 bone grafts harvested, were operated. Results are reported. The level of patient satisfaction has been high. We have had only 2 minor complications, 1 case of alopecia, corrected by a resection in local anesthesia, this inconvenient has never reported before in the literature, and another case of secondary displacement of the nasal bone graft, who required a second operation with a good result. Discussion is reported. Several methods have been used for nasal reconstruction as silicone implants and other bone donor site; but they have disadvantages like painful to the donor site, long hospitalizations, infections and extrusions, etc. The use of cranial graft has some advantages: first of all, it is less likely to resorb, because of its membranous origin, the donor site is in close proximity to the area to be grafted, there is almost no morbidity to the donor site. Recently two case reports describing major complications were published in the literature. A case of a superior sagittal sinus laceration reported by Cannella and Hopkins and a case of an intracerebral hematoma, reported by Leroy-Young. For these reasons it's important to follow strictly the surgical procedure described. We recommended this technique only to those surgeons who are experienced in cranio-facial surgery.

The clinical and radiographic results of 9 consecutive vascularized full-thickness cranial bone grafts to the midface are examined for a period of 3 to 8 years. Satisfactory contour was maintained throughout the follow-up in 5 patients with severe congenital facial deformities. Axial computerized tomography revealed complete survival of a trilaminar bone graft in each case. The complications were limited to a small area of alopecia in the midportion of one temporal scar. This relatively tedious harvest of bone is indicated for severe congenital malar and maxillary midface hypoplasia beginning at 4 years of age.

Little is known about the minimum bacterial dose required to induce infections by superficial contamination alone (i.e., not direct inoculation). This study quantified superficial rabbit calvarial bone graft contamination by exposing parietal bone grafts to Staphylococcus aureus. Two 5 x 5-mm full-thickness calvarial bone grafts were harvested from 40 rabbits and contaminated with different concentrations (range = 10(7)-10(11) colony-forming units [CFUs]/mL) of S. aureus by immersion. One graft from each rabbit was cultured immediately, and the other was inset into a calvarial donor site, fixed in place with wire, and observed for evidence of infection. At harvest (28 days postoperatively), a bacterial exposure of greater than 10(8) CFUs/mL of S. aureus was required to induce infections in the rabbit calvarial grafts (p < 0.001, Student's t-test), transmitting an infectious dose of approximately more than 10(4) CFUs per graft. These results validate the previously known dogma regarding the number of organisms needed to manifest infection [1,2] and highlight a multifold increment in bacterial count needed to transmit this infectious dose by superficial contamination alone. Such a model may be useful in investigating the efficacy of various treatment modalities of contaminated bone.

The authors report the advantages and disadvantages of the calvarial bone used as bone graft in the maxillofacial area. They review most of the parietal bone's indications and report their experience with clinical cases.

Ipriflavone, a synthetic isoflavone-derived flavonoid, was shown to have inhibitory effect on bone resorption. In order to study its mechanism of action directly on bone, 46 female Wistar rats were divided into six groups and medicated orally for 25 days as follows: groups 1 and 2 were given 1% carboxymethylcellulose solution (vehicle), groups 3, 4, 5, and 6 were administered ipriflavone at doses of 0.178, 0.356, 0.712, and 1.424 mmol/kg/day (suspended in vehicle), respectively. On the 22nd day, parathyroid glands, taken from donor rats, were transplanted in contact with the outer surface of the periosteum of both the right and the left parietal bones of rats from groups 2, 3, 4, 5, and 6. The group 1 rats underwent sham operation. Bone histomorphometry, performed on the ectocranial periosteum of parietal bones, showed that absolute erosion boundary, absolute eroded area, absolute erosion depth, number of tartrate-resistant acid phosphatase (TRAP)-positive polynucleated osteoclasts, and number of TRAP-positive mononucleated cells decreased in ipriflavone-treated rats compared with group 2 rats. The reduction was roughly proportional to the increase of drug dosage and reached statistical significance in rats of groups 5 and 6. The same parameters were extremely low in group 1 rats. Mineral apposition rate did not differ in any of the groups. Significant increase of serum calcium and significant decrease of serum phosphate were found in group 2 rats compared with group 1 rats, whereas no differences from controls were detected in ipriflavone-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

The authors have performed 13 cases of vascularized cranial bone grafts for reconstruction of maxillofacial defects since 1986. Two types of flaps were used: the parietal osteofascial flap pedicled to the parieto-temporal fascia based on the superficial temporal artery and the temporalis osteomuscular flap pedicled to the temporalis muscle based on the deep temporal artery. Zygomatico-orbital complex, maxilla and mandible were reconstructed and hemifacial microsomia was also treated. The results of vascularized cranial bone grafts pedicled to fascia were as good as those of grafts pedicled to muscle. There were no major complications. Two types of vascularized cranial bone grafts seem to be useful in reconstruction of maxillofacial defects with avascular recipient beds because of their good blood supply. The parietal osteofascial flap has additional advantages including easy rotation of the flap to the defect, particularly a mandibular defect, and versatile use of fascia without bulkiness for reconstruction of soft tissue defects. This flap can be designed as a full- or partial-thickness cranial bone graft with good vascularity. In this paper, our technique for mandibular and maxillary reconstruction using the parietal osteofascial flap is introduced, and the results compared with our temporalis osteomuscular flap technique are reported.