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The population is aging, and the prevalence of chronic wounds is increasing. Because neovascularization is essential for tissue repair and both local and systemic factors affect new blood vessel formation, we hypothesize that altering either pathway would reciprocally enhance wound healing in the aged. To test this hypothesis, p53 was locally suppressed and endothelial progenitor cells (EPCs) were systemically mobilized in a murine model of senescent wound healing.Bilateral 6-mm full-thickness stented wounds were made on the dorsum of Zmpste24 mice. Animals received weekly topical p53 small interfering RNA (siRNA) (n = 25), weekly topical nonsense siRNA (n = 25), daily subcutaneous AMD3100 injections (n = 25), or daily subcutaneous saline injections (n = 25). Wounds were photographically assessed and harvested for reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and immunostaining over 40 days. Circulating EPC levels were measured using fluorescence-activated cell sorting analysis.Local p53 siRNA significantly improved Zmpste24 wound healing (18 ± 2 vs 40 ± 3 days; P ≤ 0.0001). p53 siRNA significantly increased local provasculogenic factors (hypoxia-inducible factor 1 α, stromal cell-derived factor 1 α, and vascular endothelial growth factor; P ≤ 0.05) and decreased local proapoptotic factors (p53, PUMA, and Bax; P ≤ 0.05). Local p53 siRNA also significantly increased the number of circulating EPCs (8 ± 0.2% vs 2.6 ± 0.1%; P ≤ 0.0001). AMD3100 treatment also significantly improved wound healing (20 ± 2 vs 40 ± 3 days; P ≤ 0.0001) and increased EPCs mobilization (7.8 ± 0.4% vs 2.6 ± 0.1%; P ≤ 0.0001). In addition, systemic AMD3100 increased local provasculogenic factors (hypoxia-inducible factor 1 α, stromal cell-derived factor 1 α, and vascular endothelial growth factor; P ≤ 0.05) and decreased local proapoptotic factors (p53, PUMA, and Bax; P ≤ 0.05). Both treatments significantly increased the number of blood vessels in the wound bed (P ≤ 0.0001).The marked delay in Zmpste24 wound healing is significantly improved by local (p53 siRNA) and systemic (AMD3100) treatments. The resulting decrease in proapoptotic factors and increase in provasculogenic factors in the wound bed as well as the increased level of circulating EPCs appear to reverse age-related wound healing impairment by enhancing wound neovascularization.

Pediatric plastic and reconstructive surgery , Pediatric plastic and reconstructive surgery , کتابخانه دیجیتال دانشگاه علوم پزشکی اصفهان

Background Acellular dermal matrix (ADM) is widely used for structural or dermal replacement purposes. Given its innate biocompatibility and its potential to vascularize, we explored the possibility of ADM to function as a small interfering RNA (siRNA) delivery system. Specifically, we sought to improve ADM vascularization by siRNA-mediated inhibition of prolyl hydroxylase domain-2 (PHD2), a cytoplasmic protein that regulates hypoxia inducible factor-1α, and improve neovascularization. Materials and methods Fluorescently labeled siRNA was used to rehydrate thin implantable ADM. Pharmacokinetic release of siRNA was determined. Twelve millimeter sections of ADM reconstituted with PHD2 siRNA (nonsense siRNA as control) and applied to dorsal wounds of 40 FVB mice. Grafts were sewn in, bolstered, and covered with occlusive dressings. Photographs were taken at 0, 7, and 14 d. Wounds were harvested at 7 and 14 d and analyzed (messenger RNA, protein, histology, and immunohistochemistry). Results Release kinetics was first-order with 80% release by 12 h. By day 14, PHD2-containing ADM appeared viable and adherent, whereas controls appeared nonviable and nonadherent. Real-time reverse transcription-polymerase chain reaction demonstrated near-complete knockdown of PHD2, whereas vascular endothelial growth factor and FGF-2 were increased 2.3- and 4.7-fold. On enzyme-linked immunosorbent assay, vascular endothelial growth factor was increased more than fourfold and stromal cell-derived factor doubled. Histology demonstrated improved graft incorporation in treated groups. Immunohistochemical demonstrated increased vascularity measured by CD31 staining and increased new cell proliferation by denser proliferating cell nuclear antigen staining in treated versus controls. Conclusions We concluded that ADM is an effective matrix for local delivery of siRNA. Strategies to improve the matrix and/or genetically alter the local tissue environment can be envisioned.

Although bone repair is often a relatively rapid and efficient process, many bone defects do not heal. Because an adequate blood supply is essential for new bone formation, we hypothesized that augmenting new blood vessel formation by increasing the number of circulating vasculogenic progenitor cells (PCs) with AMD3100 and enhancing their trafficking to the site of injury with recombinant human parathyroid hormone (rhPTH) will improve healing.Critical-sized 3-mm cranial defects were trephined into the right parietal bone of C57BLKS/J 6 mice (N = 120). The mice were divided into 4 equal groups (n = 30 for each). The first group received daily subcutaneous injections of AMD3100 (5 mg/kg). The second group received daily subcutaneous injections of rhPTH (5 mg/kg). The third group received both AMD3100 and rhPTH. The fourth group received subcutaneous injections of saline. Circulating vasculogenic PC numbers, new blood vessel formation, and bony regeneration were assessed. Progenitor cell adhesion, migration, and tubule formation were assessed in the presence of rhPTH and AMD3100.Flow cytometry demonstrated that combination therapy significantly increased the number of circulating PCs compared with all other groups. In vitro, AMD3100-treated PCs had significantly increased adhesion migration, and tubule formation was assessed in the presence of rhPTH. Combination therapy significantly improved new blood vessel formation in those with cranial defect compared with all other groups. Finally, bony regeneration was significantly increased in the combination therapy group compared with all other groups.The combination of a PC-mobilizing and traffic-enhancing agent improved bony regeneration of calvarial defects in mice.

Obtaining an esthetic and functional primary surgical repair in patients with complete cleft lip and palate (CLP) can be challenging because of tissue deficiencies and alveolar ridge displacement. This study aimed to describe surgeons' assessments of presurgical deformity and predicted surgical outcomes in patients with complete unilateral and bilateral CLP (UCLP and BCLP, respectively) treated with and without nasoalveolar molding (NAM). Cleft surgeon members of the American Cleft Palate-Craniofacial Association completed online surveys to evaluate 20 presurgical photograph sets (frontal and basal views) of patients with UCLP (n = 10) and BCLP (n = 10) for severity of cleft deformity, quality of predicted surgical outcome, and likelihood of early surgical revision. Five patients in each group (UCLP and BCLP) received NAM, and 5 patients did not receive NAM. Surgeons were masked to patient group. Twenty-four percent (176/731) of surgeons with valid e-mail addresses responded to the survey. For patients with UCLP, surgeons reported that, for NAM-prepared patients, 53.3% had minimum severity clefts, 58.9% were anticipated to be among their best surgical outcomes, and 82.9% were unlikely to need revision surgery. For patients with BCLP, these percentages were 29.8%, 38.6%, and 59.9%, respectively. Comparing NAM-prepared with non-NAM-prepared patients showed statistically significant differences (P < 0.001), favoring NAM-prepared patients. This study suggests that cleft surgeons assess NAM-prepared patients as more likely to have less severe clefts, to be among the best of their surgical outcomes, and to be less likely to need revision surgery when compared with patients not prepared with NAM.

BACKGROUND Wide variations in fat graft survival have been reported. The authors hypothesize that treating the adipose tissue on Telfa gauze creates a processed lipoaspirate with a more functional adipokine profile that improves fat graft survival. METHODS Suction-assisted lipoaspirate was harvested from humans and was either processed by centrifugation, rolled on Telfa gauze, or left unprocessed. Progenitor cell populations were quantified and characterized by flow cytometry. Glycerol-3-phosphate dehydrogenase assay was used to measure the functional adipocytes. The lipoaspirates were grafted into (n = 45) wild-type mice and harvested to assess fat graft persistence. Vascular endothelial growth factor and platelet-derived growth factor-BB secretions were measured by enzyme-linked immunosorbent assay technique. RESULTS Centrifuged lipoaspirate had a greater number of progenitor cells per gram of tissue than Telfa-processed and unprocessed lipoaspirate. However, Telfa-processed lipoaspirate had a greater number of functional adipocytes (0.104 U/ml) than centrifuged (0.080 U/ml) and unprocessed lipoaspirate (0.083 U/ml) on glycerol-3-phosphate dehydrogenase assay (p < 0.05). After 10 weeks of grafting, it had greater fat graft persistence (70.9 ± 6.2 percent) than centrifuged (56.7 ± 5.5 percent) and unprocessed lipoaspirate (42.2 ± 2.7 percent) (p < 0.05). It also maintained a greater secretion of vascular endothelial growth factor and platelet-derived growth factor-BB at weeks 1 and 2 than centrifuged and unprocessed lipoaspirate. Furthermore, CD31 staining demonstrated an increase in vascular density of the Telfa-processed lipoaspirate at week 2 compared with the centrifuged lipoaspirate (37 ± 1 percent and 14 ± 4 percent per high-power field; p < 0.05). CONCLUSIONS Lipoaspirate processing technique has a significant impact on fat graft survival rate. Increasing the number of functional adipocytes by processing the fat on Telfa gauze may augment the secretion of angiogenic and mitogenic adipokines within the graft, thereby improving its survivability. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, V.

BACKGROUND Maxillary position in patients with syndromic craniosynostosis after midface distraction has been shown to be stable 1 year postoperatively. The purpose of this study is to assess midfacial position in the growing child with craniosynostosis 5 years after Le Fort III advancement with a rigid external device. METHODS Seventeen consecutive patients were identified to have the diagnosis of syndromic craniosynostosis and had undergone midface advancement [corrected]. There were 10 boys and seven girls, seven patients had Crouzon syndrome, five had Apert syndrome, and five had Pfeiffer syndrome. A standard subcranial Le Fort III osteotomy was performed. Cephalometric analysis was performed to assess the position of the maxilla. RESULTS After device removal, orbitale advanced 13.67 mm along the x axis and downward 1.70 mm along the y axis. The A point advanced 15.97 mm along the x axis and downward 1.14 mm along the y axis. At 1 year after distraction, both orbitale and A point had advanced an additional 0.47 mm and 0.24 mm along the x axis and downward 0.58 mm and 1.78 mm along the y axis, respectively. At 5 years after distraction, the orbitale moved posterior 0.58 mm and the A point advanced an additional 2.08 mm along the x axis. Orbitale and A point descended 3.23 mm and 5.2 mm along the y axis, respectively. CONCLUSION After Le Fort III advancement with distraction, the maxillary position remains stable and continues to advance minimally along the x axis and demonstrates more growth along the y axis over the long term. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.

Modern cleft surgery requires four-dimensional and functional anatomic understanding of the cleft (and noncleft) lip, nose, and alveolus. Some techniques for nasolabial repair rely more on precise anatomic geometry, whereas others afford the surgeon a more flexible design. Consistent anthropometry enables accurate assessment and reporting of long-term outcomes; such reports are needed to guide perioperative care, delineate optimal repair principles, and resolve ongoing controversies.

The Asher-McDade system is a 5-point ordinal scale frequently used to rate the components of nasolabial appearance, including nasal form and nasal symmetry, in unilateral cleft lip and palate. Although reference photographs illustrating this scale have been identified for the frontal and right profile view, no reference photographs exist for the basal view. The aim of this study was to identify reference photographs for nasal form and nasal symmetry from the basal view to illustrate this scale and facilitate its use. Four raters assessed nasolabial appearance (form and symmetry) on basal view photographs of 50 children (average age 8 years) with a repaired cleft lip. Intraclass correlation coefficients show fair to moderate inter-rater reliability. Cronbach α indicated strong agreement between raters (0.77 nasal form; 0.78 nasal symmetry; 0.80 overall), along with low duplicate measurement error and strong internal consistency between the measures. The photographs with the highest agreement among raters were selected to illustrate each point on the 5-point scale for nasal form and for nasal symmetry, resulting in the selection of 10 reference photographs. The basal view reference photograph set developed from this study may complement existing reference photograph sets for other views and facilitate rating tasks.

Bone lacunocanalicular fluid flow ensures chemotransportation and provides a mechanical stimulus to cells. Traditional static cell-culture methods are ill-suited to study the intricacies of bone biology because they ignore the three-dimensionality of meaningful cellular networks and the lacunocanalicular system; furthermore, reliance on diffusion alone for nutrient supply and waste product removal effectively limits scaffolds to 2-3 mm thickness. In this project, a flow-perfusion system was custom-designed to overcome these limitations: eight adaptable chambers housed cylindrical cell-seeded scaffolds measuring 12 or 24 mm in diameter and 1-10 mm in thickness. The porous scaffolds were manufactured using a three-dimensional (3D) periodic microprinting process and were composed of hydroxyapatite/tricalcium phosphate with variable thicknesses, strut sizes, pore sizes and structural configurations. A multi-channel peristaltic pump drew medium from parallel reservoirs and perfused it through each scaffold at a programmable rate. Hermetically sealed valves permitted sampling or replacement of medium. A gas-permeable membrane allowed for gas exchange. Tubing was selected to withstand continuous perfusion for > 2 months without leakage. Computational modelling was performed to assess the adequacy of oxygen supply and the range of fluid shear stress in the bioreactor-scaffold system, using 12 × 6 mm scaffolds, and these models suggested scaffold design modifications that improved oxygen delivery while enhancing physiological shear stress. This system may prove useful in studying complex 3D bone biology and in developing strategies for engineering thick 3D bone constructs. Copyright © 2013 John Wiley & Sons, Ltd.

The mechanotransduction mechanisms linking distraction device activation to new bone formation remain unknown. We hypothesize that the tension stress of activation during distraction osteogenesis is transmitted through lacunocanalicular fluid flow to initiate the osteogenic signaling cascade. Adult Sprague-Dawley rats (N = 24) were subjected to mandibular osteotomy and application of an external distraction device. After a 3-day latency period, half the animals (n = 12) underwent device activation at 0.25 mm twice daily for 6 days (total activation, 3 mm), and the other half (n = 12) had no activation. On day 10, the animals were injected with fluorescent reactive red lacunocanalicular tracer before killing. Mandibles were harvested, embedded, and sectioned, and reactive red epifluorescence lacunocanalicular flow was measured. Protein was harvested for focal adhesion kinase 1 (FAK1), NESPRIN1, SUN1, LAMIN A/C, and SMAD1 Western blotting as well as for bone morphogenetic protein (BMP)-2 enzyme-linked immunosorbent assay and alkaline phosphatase assay. Lacunocanalicular fluid flow was significantly greater in the distracted samples (60.5 ± 14 vs 10.3 ± 4 molecules of equivalent soluble fluorochrome per megapixel, P = 0.01). Flow distribution demonstrated the highest lacunocanalicular flow near the center of the distraction gap. Increased lacunocanalicular flow resulted in increased FAK1 (P = 0.009), NESPRIN1 (P = 0.01), SUN1 (P = 0.01), and LAMIN A/C (P = 0.008) expression. Focal adhesion kinase 1 activation in the presence of BMP-2 protein expression (P = 0.001) resulted in increased intranuclear SMAD1 phosphorylation (P = 0.04) and alkaline phosphatase activity (P0.0001). These findings suggest that activation of the distraction osteogenesis device affects cellular response through changes in lacunocanalicular fluid flow.

Delayed diabetic wound healing is, in part, the result of inadequate endothelial progenitor cell (EPC) proliferation, mobilization, and trafficking. Recently, we developed a serum-free functional culture system called the quality and quantity culture (QQc) system that enhances the number and vasculogenic potential of EPCs. We hypothesize that QQc restoration of diabetic EPC function will improve wound closure. To test this hypothesis, we measured diabetic c-kit+Sca-1+lin− (KSL) cell activity in vitro as well as the effect of KSL cell–adoptive transfer on the rate of euglycemic wound closure before and after QQc. KSL cells were magnetically sorted from control and streptozotocin-induced type I diabetic C57BL6J bone marrow. Freshly isolated control and diabetic KSL cells were cultured in QQc for 7 days and pre-QQc and post-QQc KSL function testing. The number of KSL cells significantly increased after QQc for both diabetic subjects and controls, and diabetic KSL increased vasculogenic potential above the fresh control KSL level. Similarly, fresh diabetic cells form fewer tubules, but QQc increases diabetic tubule formation to levels greater than that of fresh control cells (P < 0.05). Adoptive transfer of post-QQc diabetic KSL cells significantly enhances wound closure compared with fresh diabetic KSL cells and equaled wound closure of post-QQc control KSL cells. Post-QQc diabetic KSL enhancement of wound closure is mediated, in part, via a vasculogenic mechanism. This study demonstrates that QQc can reverse diabetic EPC dysfunction and achieve control levels of EPC function. Finally, post-QQc diabetic EPC therapy effectively improved euglycemic wound closure and may improve diabetic wound healing.

Background Disparities in diabetic foot ulcer (DFU) treatment outcomes are well described, although few studies identify risk factors contributing to disparate healing and amputation rates. In a unique academic center serving urban public, private, and veteran patients, we investigated amputation and healing rates and specific risk factors for disparate treatment outcomes. Methods A retrospective chart review of diabetic patients with a new diagnosis of a foot ulcer at geographically adjacent, but independent public, private, and Veterans Administration (VA) hospitals was conducted. Healing and lower extremity amputation outcomes were assessed. Results Across the three hospitals, 234 patients met the inclusion criteria. Patients at the VA hospital were older (mean 72.5 years; P

Nonhealing bone defects are difficult to treat. As the bone morphogenic protein and transforming growth factor beta pathways have been implicated in bone healing, we hypothesized that percutaneous Smad7 silencing would enhance signaling through both pathways and improve bone formation. Critical sized parietal trephine defects were created and animals received percutaneous injection of: agarose alone or agarose containing nonsense or Smad7 small interfering RNA (siRNA). At 12 weeks, SMADs1, 2, 3, 5, 7 and 8 levels were assessed. Smad1/5/8 osteogenic target, Dlx5, and SMAD2/3 angiogenic target, plasminogen activator inhibitor-1 (Pai1), transcription levels were measured. Noncanonical signaling through TGFβ activated kinase-1 (Tak1) and target, runt-related transcription factor 2 (Runx2) and collagen1α1 (Col1α1), transcription were also measured. Micro-computed tomography and Gomori trichome staining were used to assess healing. Percutaneous injection of Smad7 siRNA significantly knocked down Smad7 mRNA (86.3 ± 2.5%) and protein levels (46.3 ± 3.1%). The SMAD7 knockdown resulted in a significant increase in receptor-regulated SMADs (R-SMAD) (Smad 1/5/8 and Smad2/3) nuclear translocation. R-SMAD nuclear translocation increased Dlx5 and Pai1 transcription. Additionally, noncanonical signaling through Tak1 increased Runx2 and Col1α1 target transcription. Compared with animals treated with agarose alone (33.9 ± 2.8% healing) and nonsense siRNA (31.5 ± 11.8% healing), animals treated Smad7 siRNA had significantly great (91.2 ± 3.8%) healing. Percutaneous Smad7 silencing increases signal transduction through canonical and noncanonical pathways resulting in significant bone formation. Minimally invasive gene therapies may prove effective in the treatment of nonhealing bone defects.

Preoperative nasoalveolar molding (NAM) in combination with primary gingivoperiosteoplasty (GPP) reduces the need for secondary alveolar bone grafting by 60% in patients with unilateral cleft lip and palate (CL/P). Herein, we investigate the efficacy of NAM and primary GPP in patients with bilateral CL/P. All patients (n = 38) with bilateral CL/P who underwent NAM and primary GPP from 1988 to 1998 with at least 14 years of follow-up were included in this study. Panoramic and periapical radiographs were used to assess dentoalveolar bone formation. A total of 38 patients were identified with median follow-up of 18 years (range 14-26 years). Of the 27 patients who underwent bilateral GPP, 14 (51%) patients had successful dentoalveolar bone formation bilaterally and 13 (49%) had unilateral bone formation. No patient had a bilateral failure. Of the 11 patients who underwent unilateral GPP, 7 (63%) patients had successful dentoalveolar bone formation. Bilateral successful dentoalveolar bone formation following primary bilateral GPP has a dependent probability of 52% and a conditional probability of 82%.

Despite significant advances in cleft lip and palate treatment, anatomical controversies remain. Some have proposed that the width of the cleft is due to alveolar segmental displacement. Others suggest that the width is due to palatoalveolar hypoplasia. Improving our understanding of cleft anatomy may have implications for presurgical orthopedics and tissue engineering therapies. Palatoalveolar impressions of 17 noncleft children and 11 children with complete (alveolar, primary, and secondary) unilateral cleft palates were taken. Maxillary tuberosity positions and maxillary volumes were compared. Tuberosity position was determined by facebow transfer of palatoalveolar casts into geodetic datum boxes, and identification of the Cartesian coordinates (x, y, z) of the tuberosities relative to the box surfaces and Frankfurt horizontal. Maxillary volume was determined by immersing the palatoalveolar casts and measuring sand displacement. A significant difference was noted in the average tuberosity to contralateral tuberosity distance between cleft and noncleft cohorts. On average, cleft palate tuberosities were laterally displaced 8.7 mm compared with noncleft palates (P < 0.05). There was neither statistically significant alveolar segment elevation nor retroversion. A significant difference was noted in the average palatoalveolar volumes. The cleft palatoalveolar volume was 5.7 cm, and the noncleft palatoalveolar volume was 7.2 cm (P < 0.05). A palatal cleft is due to both alveolar tissue displacement and deficiency. Therefore, ideal cleft palate care should involve the correction of a displaced and deficient alveolus.

Among the craniosynostosis syndromes, Pfeiffer syndrome is notable because of high mortality and the need for multiple surgical interventions. However, it is variable in severity. We propose a new classification of Pfeiffer Syndrome to define pathology and function. A retrospective review was conducted of 42 patients with Pfeiffer syndrome treated from 1975 to 2010, the largest series reported to date. The classification was based on a functional assessment of patients in terms of respiratory, ocular, otological, and neurological status. This classification was tested by scoring and stratifying patients as follows: type A (mild problems), B (moderate problems), or C (severe problems). Patients were scored both at the time of presentation and after all surgical interventions to assess change in functional outcome. The functional classification system was compared to another previously reported. Type A patients did not have any change in postoperative functional outcomes (mean preoperative score 1.6, mean postoperative score 1.6); type B patients showed functional improvement (mean preoperative score 4.1, mean postoperative score 3.4) but type C patients (mean preoperative score 7.7, mean postoperative score 4.8) demonstrated the greatest improvement in functional scores after surgical intervention. Suture pathology did not indicate the clinical severity of phenotype, a variance from a previously published classification. The proposed classification is useful to assess severity of phenotype: respiratory, ocular, otologic, and neurologic problems are key indicators of the need for treatment. The classification can provide a helpful guide in multidisciplinary treatment planning, in reporting outcomes, and in the sharing of data among craniofacial anomalies centers.

Bone repair and regeneration are dynamic processes that involve a complex interplay between the substrate, local and systemic cells, and the milieu. Although each constituent plays an integral role in faithfully recreating the skeleton, investigators have long focused their efforts on scaffold materials and design, cytokine and hormone administration, and cell-based therapies. Only recently have the intangible aspects of the milieu received their due attention. In this review, we highlight the important influence of environmental factors on bone tissue engineering.

A serious consequence of diabetes mellitus is impaired wound healing, which largely resists treatment. We previously reported that topical application of calreticulin (CRT), an endoplasmic reticulum chaperone protein, markedly enhanced the rate and quality of wound healing in an experimental porcine model of cutaneous repair. Consistent with these in vivo effects, in vitro CRT induced the migration and proliferation of normal human cells critical to the wound healing process. These functions are particularly deficient in poor healing diabetic wounds. Using a genetically engineered diabetic mouse (db/db) in a full-thickness excisional wound healing model, we now show that topical application of CRT induces a statistically significant decrease in the time to complete wound closure compared with untreated wounds by 5.6 days (17.6 vs. 23.2). Quantitative analysis of the wounds shows that CRT increases the rate of reepithelialization at days 7 and 10 and increases the amount of granulation tissue at day 7 persisting to day 14. Furthermore, CRT treatment induces the regrowth of pigmented hair follicles observed on day 28. In vitro, fibroblasts isolated from diabetic compared with wild-type mouse skin and human fibroblasts cultured under hyperglycemic compared with normal glucose conditions proliferate and strongly migrate in response to CRT compared with untreated controls. The in vitro effects of CRT on these functions are consistent with CRT's potent effects on wound healing in the diabetic mouse. These studies implicate CRT as a potential powerful topical therapeutic agent for the treatment of diabetic and other chronic wounds.

Bone repair and regeneration is a dynamic process that involves a complex interplay between the (1) ground substance; (2) cells; and (3) milieu. Each constituent is integral to the final product, but it is often helpful to consider each component individually. While bone tissue engineering has capitalized on a number of breakthrough technologies, one of the most valued advancements is the incorporation of mesenchymal stem cells (SCs) into bone tissue engineering applications. With this new idea, however, came new found problems of guiding SC differentiation. Moreover, investigators are still working to understand which SCs source produces optimal bone formation in vitro and in vivo. Bone marrow-derived mesenchymal SCs and adipose-derived SCs have been researched most extensively, but other SC sources, including dental pulp, blood, umbilical cord blood, epithelial cells reprogrammed to become induced pluripotent SCs, among others, are being investigated. In Part II of this review series, we discuss the variety of cell types (e.g., osteocytes, osteoblasts, osteoclasts, chondrocytes, mesenchymal SCs, and vasculogenic cells) important in bone tissue engineering.

Introduction A multidisciplinary conference was convened in March 2010 with the charge to develop parameters of care for patients with craniosynostosis. The 52 participants represented 16 medical specialties and 16 professional societies. Herein, we present the dental, orthodontic, and surgical care recommendations for those with craniosynostosis, with special emphasis on craniosynostosis syndromes. Methods Plenary and small-group iterative discussions were held to draft specialty-specific parameters of care. All participants reviewed and discussed each specialty-specific document. Special care was taken to ensure cross-discipline interactions, recognizing the importance of interdisciplinary team care. Results A unified document was produced delineating longitudinal care parameters from prenatal assessment and consultation to adulthood in all the represented specialty areas. The dental and orthodontic care parameters from infancy to adulthood are explained in terms of stages of development and coordinated with interdisciplinary assessments and interventions. Conclusions The consensus document provides a detailed description of physical, functional, and cognitive development in persons with craniosynostosis and recommends staged team observations and interventions. The expectation is that the document will help to ensure state-of-the-art care for patients with craniosynostosis and provide a generally acceptable framework for collaborative studies.

BACKGROUND Coronoid process hypertrophy can be associated with a variety of congenital or acquired anomalies. There is, however, no consensus on a quantitative or objective measure to define coronoid hypertrophy. Here, the authors describe a novel analytical technique using three-dimensional computed tomographic data to accurately and reproducibly assess coronoid size and diagnose coronoid:condyle disproportion. METHODS A total of 24 patients were analyzed using three-dimensional medial axis analysis, eight with of unilateral coronoid hypertrophy, four with of bilateral coronoid hypertrophy, and 12 age-matched normal control patients. RESULTS Measurement of normal subjects (n = 12) demonstrated a coronoid:condyle volumetric ratio less than or equal to 0.5. Analysis of patients with coronoid hypertrophy demonstrated that a coronoid:condyle volumetric ratio greater than or equal to 1.0 was consistent with marked coronoid:condylar disproportion and a ratio between 0.5 and 1.0 was indicative of modest disproportion. Surface area ratios comparing coronoid with condyle were also elevated (ratio, ≥0.5) in patients with coronoid hypertrophy. CONCLUSIONS Quantitative assessment of coronoid size using three-dimensional volume and surface area analysis of computed tomographic data may be helpful to the clinician in diagnosing coronoid hypertrophy and in guiding treatment. It may also serve a role in monitoring the temporal evolution of coronoid hypertrophy in early cases that have not yet resulted in trismus or decreased interincisal opening. CLINICAL QUESTION/LEVEL OF EVIDENCE Diagnostic, IV.

Prolyl hydroxylase domain 2 (PHD2) has been implicated in several pathways of cell signaling, most notably in its regulation of hypoxia-inducible factor (HIF)-1α stability. In normoxia, PHD2 hydroxylates proline residues on HIF-1α, rendering it inactive. However, in hypoxia, PHD2 is inactive, HIF-1α is stabilized and downstream effectors such as vascular endothelial growth factor and fibroblast growth factor-2 are produced to promote angiogenesis. In the present study we utilize RNA interference to PHD2 to promote therapeutic angiogenesis in a diabetic wound model, presumably by the stabilization of HIF-1α. Stented wounds were created on the dorsum of diabetic Lepr db/db mice. Mice were treated with PHD2 small interfering RNA (siRNA) or nonsense siRNA. Wounds were measured photometrically on days 0-28. Wounds were harvested for histology, protein, and RNA analysis. Diabetic wounds treated with siRNA closed within 21±1.2 days; sham-treated closed in 28±1.5 days. By day 7, Western blot revealed near complete suppression of PHD protein and corresponding increased HIF-1α. Angiogenic mediators vascular endothelial growth factor and fibroblast growth factor-2 were elevated, corresponding to increased CD31 staining in the treated groups. siRNA-mediated silencing of PHD2 increases HIF-1α and several mediators of angiogenesis. This corresponded to improved time to closure in diabetic wounds compared with sham-treated wounds. These findings suggest that impaired wound healing in diabetes can be ameliorated with therapeutic angiogenesis.

Radiation therapy is a cornerstone of oncologic treatment. Skin tolerance is often the limiting factor in radiotherapy. To study these issues and create modalities for intervention, the authors developed a novel murine model of cutaneous radiation injury.The dorsal skin was isolated using a low-pressure clamp and irradiated. Mice were followed for 8 weeks with serial photography and laser Doppler analysis. Sequential skin biopsy specimens were taken and examined histologically. Tensiometry was performed and Young's modulus calculated.High-dose radiation isolated to dorsal skin causes progressive changes in skin perfusion, resulting in dermal thickening, fibrosis, persistent alopecia, and sometimes ulceration. There is increased dermal Smad3 expression, and decreased elasticity and bursting strength.This model of cutaneous radiation injury delivers reproducible localized effects, mimicking the injury pattern seen in human subjects. This technique can be used to study radiation-induced injury to evaluate preventative and therapeutic strategies for these clinical issues.

Diabetes is characterized by several poorly understood phenomena including dysfunctional wound healing and impaired vasculogenesis. p53, a master cell cycle regulator, is upregulated in diabetic wounds and has recently been shown to play a regulatory roles in vasculogenic pathways. We have previously described a novel method to topically silence target genes in a wound bed with small interfering (si)RNA. We hypothesized that silencing p53 results in improved diabetic wound healing and augmentation of vasculogenic mediators. Paired 4-mm stented wounds were created on diabetic db/db mice. Topically applied p53 siRNA, evenly distributed in an agarose matrix, was applied to wounds at postwound day 1 and 7 (matrix alone and nonsense siRNA served as controls). Animals were sacrificed at postwound days 10 and 24. Wound time to closure was photometrically assessed, and wounds were harvested for histology, immunohistochemistry, and immunofluorescence. Vasculogenic cytokine expression was evaluated via Western blot, reverse transcription-polymerase chain reaction, and enzyme-linked immunosorbent assay. The ANOVA/t-test was used to determine significance (p≤ 0.05). Local p53 silencing resulted in faster wound healing with wound closure at 18±1.3 d in the treated group vs. 28±1.0 d in controls. The treated group demonstrated improved wound architecture at each time point while demonstrating near-complete local p53 knockdown. Moreover, treated wounds showed a 1.92-fold increase in CD31 endothelial cell staining over controls. Western blot analysis confirmed near-complete p53 knockdown in treated wounds. At day 10, VEGF secretion (enzyme-linked immunosorbent assay) was significantly increased in treated wounds (109.3±13.9 pg/mL) vs. controls (33.0±3.8 pg/mL) while reverse transcription-polymerase chain reaction demonstrated a 1.86-fold increase in SDF-1 expression in treated wounds vs. controls. This profile was reversed after the treated wounds healed and before closure of controls (day 24). Augmented vasculogenic cytokine profile and endothelial cell markers are associated with improved diabetic wound healing in topical gene therapy with p53 siRNA.

Background: Pediatric temporomandibular joint dysfunction, resulting from either soft-tissue or skeletal disorders, may be congenital or acquired. Congenital temporomandibular joint disorders are uncommon. The authors review their experience with pediatric temporomandibular joint disorders and propose a new classification system. Methods: Clinical records, cephalograms, computed tomographic scans, magnetic resonance images, and pathologic specimens of all pediatric patients (younger than 18 years) with trismus or restricted mandibular excursion from 1976 to 2008 were reviewed. Cases were stratified according to soft-tissue or skeletal pathologic findings; skeletal abnormalities were further characterized as intracapsular or extracapsular. Results: Thirty-eight patients, ranging in age from 1 day to 18 years at diagnosis, were identified with temporomandibular joint disorders. Ten cases (26.3 percent) were attributable to soft-tissue abnormality. The remaining 28 cases (73.7 percent) were attributable to skeletal abnormality, consisting of 14 congenital and 14 acquired cases (50 percent each). Acquired skeletal deformities included 12 intracapsular ankyloses (85.7 percent) and two extracapsular ankylosis (14.3 percent) (extraarticular bone blocks). Congenital skeletal deformities accounted for five intracapsular ankyloses (35.7 percent) and nine extracapsular ankyloses (64.3 percent). Conclusions: On initial survey, the data are consistent with published reports that attribute temporomandibular joint dysfunction to acquired abnormality (i.e., trauma and infection). However, the authors observed a significantly higher percentage (50 percent) of congenital temporomandibular joint skeletal disorders than previously reported. Most congenital cases involved extracapsular abnormality (i.e., coronoid hypertrophy); only a minority of cases had glenoid-condylar fibro-osseous fusion (i.e., intracapsular ankyloses). Because the diagnosis and classification of temporomandibular joint disorders determine treatment options, the authors provide a new classification that characterizes the extent of capsular involvement.

Radiotherapy, an essential modality in cancer treatment, frequently induces fibrotic processes in the skin, including accumulation of extracellular matrix. Transforming growth factor-β is essential in regulating extracellular matrix gene expression and is dependent on Smad3, an intracellular mediator/transcription factor. Our study characterized the genetic expression involved in extracellular matrix accumulation during radiation-induced fibrosis. We performed Smad3 gene silencing in an attempt to abrogate the effects of radiation.Laboratory research.University laboratory.C57 murine dermal fibroblasts were irradiated with 20 Gy RNA isolated (0, 6, 12, 24, 48, 72 hours postirradiation) and mRNA analyzed (reverse transcriptase polymerase chain reaction) for known regulators (Smad3, interleukin-13 [IL-13]), tumor necrosis factor-α [TNF-α]) and mediators of fibrosis (collagen 1A1 [Col1A1]), TGF-β, matrix metalloprotease-1 and -2 (MMP-1, MMP-2), and tissue inhibitor of metalloprotease-1 (TIMP-1). Smad3 gene expression was silenced using siRNA in an effort to restore an unirradiated gene profile.Following irradiation, there was a steady increase in mRNA expression of Smad3, IL-13, TGF-β, Col1A1, MMP-2, TIMP-1, with peak at 12 to 24 hours and subsequent decline by 72 hours. TNF-α expression remained elevated throughout. MMP-1 showed minimal expression initially, which decreased to negligible by 72 hours. Inhibition of Smad3 significantly decreased expression of Col1A1, TGF-β, MMP-2, and TIMP-1. IL-13 and TNF-α expression was not affected by Smad3 silencing.We have characterized the early-phase mRNA expression profiles of the major mediators of radiation-induced fibrosis. Smad3 siRNA effectively abrogated the elevation of Col1A1, TGF-β, TIMP-1, and MMP-2. IL-13 and TNF-α were unaffected by Smad3 silencing and appear to be minor regulators in fibrosis. These findings suggest a therapeutic rationale for Smad3 silencing in vivo.

OBJECTIVE Progenitor cells (PCs) contribute to postnatal neovascularization and tissue repair. Here, we explore the mechanism contributing to decreased diabetic circulating PC number and propose a novel treatment to restore circulating PC number, peripheral neovascularization, and tissue healing. RESEARCH DESIGN AND METHODS Cutaneous wounds were created on wild-type (C57BL/J6) and diabetic (Leprdb/db) mice. Blood and bone marrow PCs were collected at multiple time points. RESULTS Significantly delayed wound closure in diabetic animals was associated with diminished circulating PC number (1.9-fold increase vs. 7.6-fold increase in lin−/sca-1+/ckit+ in wild-type mice; P < 0.01), despite adequate numbers of PCs in the bone marrow at baseline (14.4 ± 3.2% lin−/ckit+/sca1+ vs. 13.5 ± 2.8% in wild-type). Normal bone marrow PC mobilization in response to peripheral wounding occurred after a necessary switch in bone marrow stromal cell-derived factor-1α (SDF-1α) expression (40% reduction, P < 0.01). In contrast, a failed switch mechanism in diabetic bone marrow SDF-1α expression (2.8% reduction) resulted in impaired PC mobilization. Restoring the bone marrow SDF-1α switch (54% reduction, P < 0.01) with plerixafor (Mozobil, formerly known as AMD3100) increased circulating diabetic PC numbers (6.8 ± 2.0-fold increase in lin−/ckit+, P < 0.05) and significantly improved diabetic wound closure compared with sham-treated controls (32.9 ± 5.0% vs. 11.9 ± 3% at day 7, P > 0.05; 73.0 ± 6.4% vs. 36.5 ± 7% at day 14, P < 0.05; and 88.0 ± 5.7% vs. 66.7 ± 5% at day 21, P > 0.05, respectively). CONCLUSIONS Successful ischemia-induced bone marrow PC mobilization is mediated by a switch in bone marrow SDF-1α levels. In diabetes, this switch fails to occur. Plerixafor represents a potential therapeutic agent for improving ischemia-mediated pathology associated with diabetes by reducing bone marrow SDF-1α, restoring normal PC mobilization and tissue healing.

Large temple and suprabrow lesions can pose a reconstructive challenge. When the lesion extends anterior to the hairline, esthetically acceptable local flaps may be difficult to design. We describe a modified scalp flap (ie, part Converse scalping flap and part scalp rotation flap) that can be tailored to reconstruct a variety of difficult temple and suprabrow lesions while simultaneously maintaining eyebrow position. The modified scalp flap is raised in a subgaleal plane until approximately 2.5 cm above the brow. At this level, dissection proceeds in the subcutaneous plane to protect the frontal branch of the facial nerve and to keep the flap thin. (The key to the modified scalp flap is the dissection plane change that protects the frontal branch of the facial nerve.) The extent of posterior subgaleal dissection is dictated by the amount of anterior rotation necessary. A temporal dog-ear is removed subfollicularly to permit modified flap rotation and preserve the superficial temporal artery. The modified scalp flap has been used to reconstruct temple and suprabrow lesions in 10 patients ranging in age from 4 months to 22 years. There were no complications. Four typical cases are presented. Temple and suprabrow lesions can be excised and successfully reconstructed in one stage using a modified scalp flap that is extended from the hair-bearing scalp onto the glabrous skin of the forehead. This novel modified scalp flap prevents eyebrow/hairline distortion and avoids facial nerve injury.

The study of human autologous fat grafting has been primarily anecdotal. In this study, the authors aim to develop a murine model that recapitulates human fat grafting to study the fate of injected fat and the cell populations contained within.The authors' method of fat harvesting and refinement has been described previously. The authors injected nude and tie2/lacZ mice with 2 ml of human lipoaspirate placed on the dorsal surface in a multipass, fan-like pattern. Fatty tissue was injected in small volumes of approximately 1/30 ml per withdrawal. The dorsal skin and associated fat was excised at various time points. Sections were stained with hematoxylin and eosin and cytochrome c oxidase IV. Transgenic tie2/lacZ samples were stained with X-galactosidase. At the 8-week time point, volumetric analysis was performed.Volumetric analysis at the 8-week time point showed 82 percent persistence of the original volume. Gross analysis showed it to be healthy, nonfibrotic, and vascularized. Hematoxylin and eosin analysis showed minimal inflammatory or capsular reaction, with viable adipocytes. Fat grafted areas were vascularized with multiple blood vessels. Cytochrome c oxidase IV human-specific stain and beta-galactosidase expression revealed these vessels to be of human origin.The authors have developed a murine model with which to study the fate of injected lipoaspirate. There is a high level of persistence of the grafted human fat, with minimal inflammatory reaction. The fat is viable and vascularized, demonstrating human-derived vessels in a mouse model. This model provides a platform for studying the populations of progenitor cells known to reside in lipoaspirate.

BACKGROUND This article aims to assess the spectrum of unfavorable events or incidents encountered during mandibular distraction and to evaluate the difference in the incident rates among the following treatment groups: (1) native bone distraction using an external device, (2) native bone distraction using an internal device, and (3) grafted bone distraction using an external device. METHODS This retrospective study examined the records of 141 patients treated by mandibular distraction over a 16-year period. Of the total 141 patients, 56 underwent unilateral mandibular distraction and 85 underwent bilateral mandibular distraction, contributing to a total of 226 sided distraction procedures. The number of procedures performed on native bone using external devices was 149, versus 41 internal devices. There were 36 distractions performed on grafted bone with external devices. Incidents were broadly classified into three groups based on a severity index. A minor incident was one that resolved satisfactorily with minimal or no invasive intervention. A moderate incident was one that resolved satisfactorily with moderate clinical intervention. A major incident was one that did not resolve or could not be resolved with surgical intervention, and compromised treatment outcome. RESULTS The major incident rate was 5.31 percent (total of 226 distraction procedures). A higher rate of major incidents was observed when distracting grafted bone. The overall minor incident rate was 26.99 percent and the moderate incident rate was 20.35 percent. CONCLUSION Mandibular distraction can be considered a safe and predictable procedure for lengthening/augmenting the mandible in patients with lower jaw deficiencies.

Impaired diabetic wound healing is due, in part, to defects in mesenchymal progenitor cell tracking. Theoretically, these defects may be overcome by administering purified progenitor cells directly to the diabetic wound. The authors hypothesize that these progenitor cells will differentiate into endothelial cells, increase wound vascularity, and improve wound healing.Lineage-negative progenitor cells were isolated from wild-type murine bone marrow by magnetic cell sorting, suspended in a collagen matrix, and applied topically to full-thickness excisional dorsal cutaneous wounds in diabetic mice. Application of lineage-positive hematopoietic cells or acellular collagen matrix served as comparative controls (n = 16 for each group; n = 48 total). Time to closure and percentage closure were calculated by morphometry. Wounds were harvested at 7, 14, 21, and 28 days and then processed, sectioned, stained (lectin/DiI and CD31), and vascularity was quantified.: Wounds treated with lineage-negative cells demonstrated a significantly decreased time to closure (14 days) compared with lineage-positive (21 days, p = 0.013) and collagen controls (28 days, p = 0.004), and a significant improvement in percentage closure at 14 days compared with the lineage-positive group (p0.01) and the collagen control (p0.01). Fluorescently tagged lineage-negative cells remained viable in the wound for 28 days, whereas lineage-positive cells were not present after 7 days. Lineage-negative, but not lineage-positive, cells differentiated into endothelial cells. Vascular density and vessel cross-sectional area were significantly higher in lineage-negative wounds.Topical progenitor-cell therapy successfully accelerates diabetic wound closure and improves wound vascularity.

The hedgehog family of morphogens (sonic [Shh], Indian, and desert hedgehog) are central regulators of embryologic growth and tissue patterning. Although recent work implicates Shh in postnatal tissue repair and development, conclusive evidence is lacking. Here, we demonstrated the importance of Shh in wound repair, by examining the effects of cyclopamine, a specific inhibitor of the Shh signaling cascade, on tissue repair. Using a murine-splinted excisional wound model, which attenuates wound contraction in this loose-skinned rodent, we established that, by all measures (wound closure, epithelialization, granulation formation, vascularity, and proliferation), wound healing was profoundly impaired when Shh signaling was disrupted. Because embryonic disruption of Shh is associated with distinct phenotypic defects, our findings invite investigation of the potential role of Shh signaling under postnatal conditions associated with disregulated wound healing.

Large acquired intracranial defects can result from trauma or surgery. When reoperation is required because of infection or tumor recurrence, management of the intracranial dead space can be challenging. By providing well-vascularized bulky tissue, intracranial microvascular free flaps offer potential solutions to these life-threatening complications. A multi-institutional retrospective chart and radiographic review was performed of all patients who underwent microvascular free-flap surgery for salvage treatment of postoperative intracranial infections between 1998 and 2006. A total of six patients were identified with large intracranial defects and postoperative intracranial infections. Four patients had parenchymal resections for tumor or seizure and two patients had posttraumatic encephalomalacia. All patients underwent operative debridement and intracranial free-flap reconstruction using the latissimus dorsi muscle ( N = 2), rectus abdominis muscle ( N = 2), or omentum ( N = 2). All patients had titanium ( N = 4) or Medpor ( N = 2) cranioplasties. We concluded that surgery or trauma can result in significant intracranial dead space. Treatment of postoperative intracranial infection can be challenging. Vascularized free tissue transfer not only fills the void, but also provides a delivery system for immune cells, antibodies, and systemically administered antibiotics. The early use of this technique when intracranial dead space and infection coexist is beneficial.

The application of distraction osteogenesis is an effective treatment for mandibular deficiencies. A priori, a horizontal vector of distraction was hypothesized to produce horizontal movement of the mandible and a vertical vector of distraction to produce primarily downward vertical elongation of the ramus. This study was designed to test this hypothesis.A retrospective clinical and radiographic review was conducted of all patients who underwent bilateral, uniplanar distraction with an external device at the New York University Medical Center between October of 1990 and February of 2004 (n = 185). A subset of 15 patients was identified who satisfied inclusion criteria and had adequate predistraction and postdistraction lateral cephalograms. Cephalometric tracings were made and multiple landmarks were assessed before and after distraction.A strong correlation was noted between the vector of distraction and rotation of the symphyseal plane, movement of the mandibular symphysis, and change in interocclusal angle. A horizontal vector of distraction resulted in minimal counterclockwise rotation of the symphyseal plane, greater downward vertical translation of the mandibular symphysis, and minimal closure of an anterior open bite. In contrast, a vertical vector resulted in greater counterclockwise rotation of the symphyseal plane, greater horizontal projection of the mandibular symphysis, and greater closure of an anterior open bite. Mathematical formulas were derived to correlate the distraction vector and mandibular movements.Successful distraction is dependent on accurate prediction of outcomes. This study demonstrates that the vector of distraction predictably affects the mandibular response during bilateral distraction osteogenesis but contradicts the a priori hypothesis.

The bony biochemical environment is an active and dynamic system that permits and promotes cellular functions that lead to matrix production and ossification. Each component is capable of conveying important regulatory cues to nearby cells, thus effecting gene expression and changes at the cytostructural level. Here, we review the various signaling molecules that contribute to the active and dynamic nature of the biochemical system. These components include hormones, cytokines, and growth factors. We describe their role in regulating bone metabolism. Certain growth factors (i.e., TGF-beta, IGF-1, and VEGF) are described in greater detail because of their potential importance in developing successful tissue-engineering strategies.

While it has been long appreciated that biomechanical forces are involved in bone remodeling and repair, the actual mechanism by which a physical force is translated to the corresponding intracellular signal has largely remained a mystery. To date, most biomechanical research has concentrated upon the effect on bone morphology and architecture, and it is only recently that the complex cellular and molecular pathways involved in this process (called mechanotransduction) are being described. In this paper, we review the current understanding of bone mechanobiology and highlight the implications for clinical medicine and tissue engineering research.

Summary Introduction Methyl methacrylate is a biologically inert alloplastic material that is commonly used to rebuild the calvarial vault. Since methyl methacrylate does not permit tissue incorporation it is susceptible to displacement and/or fracture. In order to increase the tensile strength of methyl methacrylate onlay cranioplasties, we use wire reinforced masonry techniques. Patient A 56-year-old female presents with forehead asymmetry due to displacement and fracture of a silicone alloplastic implant. This patient, treated with onlay wire reinforced methyl methacrylate, demonstrates the utility of this novel technique. Results Wire is passed through 2-mm outer cortex tunnels like spokes on a wheel, around the perimeter of the defect to form a rebar grid. Methyl methacrylate is poured onto the rebar grid and contoured after it solidifies. Conclusions Wire reinforced methyl methacrylate is a simple technique to improve the tensile strength of calvarial alloplastic reconstructions.

Although recent studies indicate that regional dura mater influences the fate of the overlying cranial suture, little is known about the assembly of extracellular matrix (ECM) molecules within the patent and fusing murine cranial suture complexes. Confocal laser scanning microscopy was used to study ECM assembly within patent and fusing cranial suture complexes. Coronal sections (20 microm thick) of patent sagittal (SAG) and fusing posterior frontal (PF) sutures from postnatal 8-, 14-, and 18-day-old Sprague-Dawley rats were scanned in 0.5-microm increments, and images were collected consecutively to create a z-series for three-dimensional reconstruction. Spatial and temporal collagen arrangements were compared between SAG and PF sutures by measuring interfiber distance, fiber thickness, and total collagen surface area at each time point. We demonstrate that on day 8 (before the onset of suture fusion), collagen bundles are randomly arranged in both the SAG and PF sutures. By day 14 (midfusion period), there was a statistically significant reduction in total collagen surface area (80.5% versus 67.4%; P < 0.05) as the collagen bundles were organized into orthogonal lattices along the anterior and endocranial margins of the PF suture. Furthermore, new bone matrix deposition was observed along the edges of these organized collagen bundles. In contrast, collagen within the SAG suture remained randomly arranged and unossified. By day 18 (late fusion period), the PF suture was completely fused except for the posterior-ectocranial portion. This patent section of the PF suture contained a highly organized mineralizing orthogonal collagen lattice. The total collagen surface area in the day-18 PF suture continued to decline compared with the day-8 PF suture (80.5% versus 55.6%; P < 0.05). In the day-18 SAG suture, the collagen bundles remained randomly arranged, and the total surface area did not change. The same analysis was performed in a human pathologic fusing and patent suture. Similar results were observed. The total collagen surface area significantly decreased in the pathologic fusing human suture compared with the patent suture (92.8% versus 60.6%; P < 0.05). Moreover, the pathologically fusing suture contained a highly organized mineralizing orthogonal collagen lattice. This is the first analysis of collagen patterns in patent and fusing cranial sutures.

Distraction osteogenesis is a valuable clinical tool; however the molecular mechanisms governing successful distraction remain unknown. We have used a uniaxial in vitro strain device to simulate the uniaxial mechanical environment of the interfragmentary distraction gap.Using the Flexcell system, normal human osteoblasts were subjected to different levels of cyclical uniaxial mechanical strain. Cellular morphology, proliferation, migration, and the expression of angiogenic (vascular endothelial growth factor [VEGF] and fibroblast growth factor-2 [FGF-2]) and osteogenic (osteonectin, osteopontin, and osteocalcin) proteins and extracellular matrix molecules (collagen IalphaII) were analyzed in response to uniaxial cyclic strain.Osteoblasts exposed to strain assumed a fusiform spindle-shaped morphology aligning parallel to the axis of uniaxial strain and osteoblasts exposed to strain or conditioned media had a 3-fold increase in proliferation. Osteoblast migration was maximal (5-fold) in response to 9% strain. Angiogenic cytokine, VEGF, and FGF-2, increased 32-fold and 2.6-fold (P0.05), respectively. Osteoblasts expressed greater amounts of osteonectin, osteopontin, and osteocalcin (2.1-fold, 1.8-fold, 1.5-fold respectively, P0.01) at lower levels of strain (3%). Bone morphogenic protein-2 production increased maximally at 9% strain (1.6-fold, P0.01). Collagen I expression increased 13-, 66-, and 153-fold in response to 3, 6, and 9% strain, respectively.Uniaxial cyclic strain using the Flexcell device under appropriate strain parameters provides a novel in vitro model that induces osteoblast cellular and molecular expression patterns that simulate patterns observed in the in vivo distraction gap.

Gluteal augmentation is increasingly common. However, few studies have quantitatively reported postoperative gluteal projection. This study compared three different standardized instruments (i.e., radiographic, sonographic, and anthropometric) for quantifying gluteal projection after lumbar-hip dermal fat rotational flap to identify a simple, cost-efficient valid instrument. A total of 10 women ages 35 to 68 years (mean, 47.3 years) with skin flaccidity and gluteal ptosis underwent bilateral lumbar-hip dermal fat rotation flap gluteal augmentation (20 procedures). Gluteal projection was measured 1 week preoperatively and 8 months postoperatively using computerized axial tomography (CAT) scan, ultrasound, and anthropometry. The CAT scan measured 1.40 cm of projection on the left (p

Background: Silicone chin augmentation remains a popular treatment for microgenia because its placement appears deceptively simple. However, when extrusion, displacement, capsular contracture following implant removal, overaugmentation, or malposition occurs, a revision operation may be required. Secondary chin surgery is challenging because (1) implant removal alone may produce a disfigured chin; and (2) placement of a new implant in an oversized misshapen pocket demands precision, control, and reliability. Methods: The textured implant may be placed by means of an intraoral or extraoral route. The extraoral route is usually chosen except when transoral procedures (e.g., mentalis suspension) are required. The superior 30 to 50 percent of a standard textured implant is always removed and then tapered anteriorly at a 45-degree angle to reduce its sharp front edge. The lateral wings are also reduced and tapered. Two pilot holes are drilled in each half of the implant and then it is divided in the midline. Each half is inserted and secured individually. The medial screw is placed first and nearly fully tightened. Then, holding the implant exactly along the inferior border of the mandible, the distal screw is placed and both screws are tightened completely. The lower border of the implant should be exactly along the lower border of the mandible. The soft tissues are closed in three layers over a drain. Results: This technique has been used to treat more than 100 patients. Selected photographs illustrate this technique. Conclusion: This article explains how to place a textured implant efficiently and effectively under light premedication and local anesthesia.

Treatment of macrogenia can be a challenging problem. In this article, the authors provide novel insights for treatment of a previously poorly treated problem. The authors have developed anatomical insights that facilitate the subtly difficult preoperative evaluation of the large chin and, when applied appropriately, will provide uniformly pleasing results.A retrospective review of the senior author's (B.M.Z.) patient records was performed. More than 50 cases of macrogenia were identified. As previously described, almost all of the cases were performed under local anesthesia with oral premedication only.This article demonstrates why prior modalities such as intraoral burring and lower border setback failed to treat the variety of large chins properly. The nine critical factors the surgeon must consider in developing a successful surgical plan are outlined. The surgical plan is not primarily based on radiographs as much as on direct tactile and visual analysis of the sublabial structures both in repose and while smiling. Crucial aspects of the operative technique are highlighted.The large chin can be approached with confidence if nine parameters are appreciated. The authors have outlined these key variables that facilitate proper preoperative topographic analysis of the large chin. Once these variables are appreciated, an appropriate surgical plan can be formulated.

The ability to affect gene expression via topical therapy has profound therapeutic implications for conditions characterized by open wounds including cutaneous neoplasms, thermal injury, skin disorders and dysfunctional wound healing. Specifically targeting local gene expression avoids systemic toxicity and simplifies treatment. We have developed a new method of topical matrix-based short interfering RNA application to precisely and effectively silence local gene expression in nondelimited wounds.

Background: Free tissue transfer for adult mandibular reconstruction is a well-established technique; however, there are few reports of pediatric microvascular lower jaw reconstruction. Methods: This retrospective study was undertaken to review the range of indications, choices, safety, and efficacy of pediatric free tissue transfer to the lower jaw. All patients underwent a parascapular, scapular, or fibula free tissue transfer. Flap choice was based on preoperative clinical examination, radiographic findings, need for linear or multiplanar mandibular reconstruction, need for dental restoration, severity of soft-tissue deficit, and peroneal artery anatomy. Results: Over a 10-year period (1989 to 1999), we performed eightfree tissue transfers to reconstruct the mandibles of seven children, aged 6 to 17 years. Indications included radiation-induced hypoplasia (n = 1), postsurgical resection of fibrous dysplasia (n = 1), hemifacial microsomia (n = 3), Robin sequence with severe micrognathia (n = 1), and osteomyelitis (n = 1). The authors transferred four parascapular osseocutaneous, two scapular osseocutaneous, one fibular osseocutaneous, and one fibular osseous flap to reconstruct five ramus, four condyle, and two subtotal mandibular defects. All bony defects were successfully bridged and all osseous flaps successfully integrated. Postoperatively, mandibular symmetry and Angle class I occlusion were restored in all patients throughout the 10.5-year follow-up period (range, 9 to 14 years). Two patients received osseointegrated dental implants. Our only complication was the partial loss of a skin paddle. Conclusion: Microvascular reconstruction of the pediatric mandible, in selected patients, is a safe, reliable procedure that provides the bone stock and soft tissue necessary to restore normal maxillomandibular growth and dental rehabilitation.

Wound surface area changes over multiple weeks are highly predictive of the wound healing process. Furthermore, the quality and quantity of the tissue in the wound bed also offer important prognostic information. Unfortunately, accurate measurements of wound surface area changes are out of reach in the busy wound practice setting. Currently, clinicians estimate wound size by estimating wound width and length using a scalpel after wound treatment, which is highly inaccurate. To address this problem, we propose an integrated system to automatically segment wound regions and analyze wound conditions in wound images. Different from previous segmentation techniques which rely on handcrafted features or unsupervised approaches, our proposed deep learning method jointly learns task-relevant visual features and performs wound segmentation. Moreover, learned features are applied to further analysis of wounds in two ways: infection detection and healing progress prediction. To the best of our knowledge, this is the first attempt to automate long-term predictions of general wound healing progress. Our method is computationally efficient and takes less than 5 seconds per wound image (480 by 640 pixels) on a typical laptop computer. Our evaluations on a large-scale wound database demonstrate the effectiveness and reliability of the proposed system.