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After studying this article, the reader should be able to understand how various implants, osteotomies, and reductive tissue techniques affect the aesthetic outcomes of chin reshaping surgery. The roles of standard versus custom chin implants, the operative steps and indications for a bony genioplasty and the techniques for chin reduction are described with emphasis on proper patient selection and avoiding their common complications.

After studying this article, the reader should be able to understand the two basic types of implants for aesthetic augmentation of the jaw angles and the aesthetic goals in using them. The operative steps for surgical placement are described with emphasis on avoiding the common complications of jaw angle implants. The indications for the use of standard versus custom jaw angle implants are also described.

After studying this article, the reader should be able to understand the basic concepts of aesthetic reshaping of the forehead and the different methods to make those upper facial contour changes. The operative techniques for bony forehead and brow bone reduction and biomaterials for forehead and brow bone augmentation are described. Innovations in bony reduction and implant augmentation methods are emphasized.

Facial augmentation is a growing field, secondary to the appreciation of the changes seen in the facial skeleton with aging and the growing acceptance/popularity of facial fat grafting and facial fillers. In addition, it plays a significant role in patients with congenital facial deficiencies as well as those interested in facial feminization/masculinization surgery. Several facial implants are discussed in this article including classic facial implants such as malar, submalar, chin, and prejowl implants as well as newer facial implants such as mandible, temporal, forehead, and skull implants. Special care is given to the postoperative care of these implants. Custom-made implants with three-dimensional computed tomography reconstruction are also discussed

Orthognathic surgery for occlusal improvement commonly requires preoperative and postoperative orthodontic treatments to fine-tune intercuspation. This report focuses on the feasibility, treatment goals, and outcomes of orthognathic surgery in a series of patients with congenital dentofacial anomalies who were considered ineligible for or noncompliant with orthodontic treatment. Despite suboptimal occlusal outcomes, the orthognathic procedures resulted in tangible benefits for the patients. We conclude that surgical treatment without concomitant orthodontics is a viable option in selected patients.

The authors examined the efficacy of adipose stem cells, when supplied either alone or in platelet-rich fibrin gels, to improve wound healing.A porcine full-thickness wound model was used to compare six topical treatments: platelet-poor plasma; platelet-rich plasma; autologous adipose stem cells plus platelet-poor plasma; autologous adipose stem cells plus platelet-rich plasma; allogeneic adipose stem cells containing green fluorescent protein plus platelet-poor plasma; and saline (control). One week after isolation, adipose stem cells were applied to full-thickness wounds on the paraspinal and thoracic regions of three pigs (44 wounds per pig; each treatment was applied to eight separate wounds). Each wound was monitored over 21 days for closure, cosmesis, and histopathology.There was no significant difference in the reepithelialization rate, but treatments containing adipose stem cells demonstrated increased microvessel densities (31.75 +/- 5.73 vessels/cm2 versus 7.93 +/- 3.61 vessels/cm2) compared with groups without adipose stem cells. Wound cosmesis was improved in the adipose stem cell plus platelet-rich plasma group compared with other treatment groups (p0.05). Vascular endothelial growth factor levels detected in matrices containing adipose stem cells were approximately 7-fold higher compared with platelet-rich plasma or platelet-poor plasma (p0.05). Localization of transgenic green fluorescent protein plus adipose stem cells indicated incorporation near neovasculature.In normal healing wounds, adipose stem cells appear to enhance the healing process only when provided in a fibrin gel vehicle containing a number of complementary wound-healing trophic factors. Perivascular adipose stem cell localization suggests a function in enhancing blood supply through providing physical and paracrine support to newly forming vessels.

Body-contouring implants are becoming increasingly popular and more accepted and requested for aesthetic purposes. These implants must be placed in a safe and reproducible plane of anatomic dissection for a successful long-term outcome. Poor implant placement techniques result in greater complications such as asymmetry, implant migration, capsular contracture, and infection. This article discusses (1) the history and the evolution of body-contouring implants, (2) the different techniques and dissection planes in which to put the implants in the calf, gluteal, pectoral, and triceps/biceps areas, and (3) the complications associated with the different implantation techniques. The different anatomical areas that have been treated with solid silicone implants are the gluteus, pectoral, calf, deltoids, biceps, triceps, and trapezium. Determining the ideal plane for implant placement is the most important surgical goal for satisfactory aesthetic results. Aesthetic contouring of the chest, back, arms, buttocks, and calf can be done safely with solid silicone implants. Proper pocket dissection and location are paramount to successful implant placement and decreased complications.

Purpose A retrospective review of a single institution's 20-year experience of complications and reoperation rates after surgery for primary craniosynostosis correction. Methodology A retrospective chart review of all patients (n = 376) undergoing primary surgery for craniosynostosis was conducted. The charts were analyzed for diagnosis, sex, syndromic involvement, age at operation, type of fixation, complications, and reoperations. Complications were defined as any event requiring prolonged hospitalization or readmission secondary to the surgical procedure, reoperation, or mortality. Reoperative rates were classified into major (e.g., repeat craniotomy, cranioplasty) or minor (e.g., hardware removal, wound closure). Results After excluding patients for length of follow-up less than 6 months (n = 23), inadequate verification of all data (n = 21), and prior neurosurgical craniectomy (n = 18), a total of 314 patients were identified. The percentage of patients with complications and reoperations was 39.2% (n = 123). The rates of major reoperation (n = 72), minor reoperation (n = 41), and various complications (n = 10) were 22.9%, 13.1%, and 3.2%, respectively. No mortalities were identified. Conclusions Differing types of fixation, diagnosis of syndrome, and multiple-suture craniosynostosis were statistically correlated to increased reoperative rates. Age at initial operation and sex were not correlated to increased reoperative rates. Finally, this institution's complication and reoperative rates compare with other published results.

After studying this article, the participant should be able to: 1. Describe the historical origins of modern cephalometry. 2. Identify common landmark points on the lateral cephalogram. 3. Describe multiple common clinical uses for cephalometry. 4. Exhibit knowledge of developments in imaging and analysis alternatives. Interest in the dimensions of the human head has been present since antiquity. Proportional analysis and measures from cadaveric specimens led to the development of radiologic image capture and analysis on living subjects. These techniques were originally applied to establishing normative values, documenting growth, and diagnosing dentofacial disharmonies. This article reviews the origins of cephalometric methodology and current developments and applications. The authors conducted a MEDLINE search and review of all English language articles using the keywords “cephalometric” and “cephalometrics.” Cephalometrics have undergone substantial use and development since the introduction of radiologic imaging on living human subjects in 1931. Although frequently associated with orthognathic surgery, cephalometrics have been applied to a number of conditions involving altered craniofacial morphology. Advances in imaging and computing have led to increased interest in three-dimensional and non–x-ray–based assessment of the human head. Mathematical models have been applied to standard cephalometric information to increase the descriptive accuracy of the complex shapes involved. Cephalometric techniques and analyses are versatile tools that can be applied to a wide variety of clinical scenarios involving the craniofacial region. New technologies and expanded applications promise to continue the development and use of this well-established methodology.

The behavior of bioabsorbable plates and screws after implantation is a dynamic process that results in dimensional changes of the devices after surgery. Bioabsorbable plates frequently are recognized as changing because of their size, but bioabsorbable screws are less appreciated in this regard. How bioabsorbable screws may change after placement and whether their manufacturing method has an influence on size and shape after implantation needs further study. Using 1.5-mm diameter screws made of an oriented copolymer of 82% poly-L-lactic acid and 18% polyglycolic acid (LactoSorb copolymer), screw dimensions were measured before and after soaking in an in vitro pH 7.4, 37 degrees C buffer environment. After 33 days of exposure to buffer, there were no changes in the physical appearance of the screws, and there was no change in dimensions or shape. The orientation of polymer materials in a bioabsorbable screw device improves its strength and can retard the rate of hydrolysis. However, the residual stresses in oriented screws theoretically can potentiate dimensional shift in the implants during hydrolysis. That such shift did not occur during the early phase of hydrolysis provides further evidence of the mechanism by which these types of screws can maintain biomechanical function throughout the bone-healing phase of the craniofacial skeleton.

Bone healing is a complex and multifactorial process. As such, there are numerous steps in the process to which intervention can be directed. This has given rise to many bone graft technologies that have been used to regenerate bone, creating, perhaps, a bewildering array of options. The options that surgeons have the most familiarity with are the ones that have been available the longest (i.e., autograft and allograft). Although useful for the widest spectrum of clinical applications, limitations of these grafts has prompted the development of new materials. Demineralized bone matrix formulations and synthetic ceramic materials are now being used with greater frequency. These biomaterials have demonstrated their usefulness in facial plastic and reconstructive surgery with their ability to augment and replace portions of the craniofacial skeleton. The purpose of this article is to describe and discuss the allograft and alloplastic bone grafting technologies so that the reader can consider each in the context of the others and gain a better appreciation for how each fits into the universe of existing and emerging treatments for bone regeneration.

Bone grafting of the alveolar cleft is an important component of the comprehensive care of the cleft lip and palate patient. Although debate exists regarding the optimal timing of the procedure, one approach is the placement of a rib graft in the alveolar cleft before eruption of the deciduous canine (primary alveolar bone graft). Since 1982, primary alveolar bone grafting has been performed at our institution in more than 300 patients. Because little is reported in the literature on primary alveolar bone grafting in general, an experienced surgical technique and protocol are lacking. Our surgical technique for rib graft harvest as well as alveolar bone graft placement in the infant cleft alveolus is described.

Learning Objectives: After studying this article, the participant should be able to: 1. Describe the differing types of congenital clefting defects that extend outward from the perioral region. 2. Define the sites of anatomical disruption and deformities that these types of facial clefts cause. 3. Describe the cause and incidence, if known, of orofacial clefts and their inheritance/transmission risks. Background: Clefts of the orofacial region are among the most common congenital facial defects. The clinical presentation is usually that of a lateral cleft of the lip through the philtrum with or without extension through the palatal shelves. However, atypical forms of clefts with lip involvement also occur in a variety of patterns, some of which are embryologically predictable; others are not. Methods: An overview of the embryology, cause, and incidence of this diverse and interesting group of congenital orofacial clefts is presented. Results: Clefts involving the lateral upper lip; median upper lip; and oblique facial, lateral facial, and median mandibular regions are reviewed. Conclusions: This review of orofacial malformations describes clefting anomalies that emanate from the mouth and lips. As the causes of orofacial clefts are better understood, it is becoming clear that a complex interplay between genetic and environmental variables causes these clefts. Future study of orofacial clefts will require increasingly sophisticated methods of elucidating these subtle interactions.

The use of the rib for primary alveolar cleft bone grafting offers one of the few donor sites for grafting under one year of age. Its use in 211 patients in an 11 year period revealed no morbidity other than a small donor scar. Rib grafting in infants differs significantly from that in teenagers and adults with minimal pain, no risk of pneumothorax when properly performed, and more than an adequate stock of bone for the alveolar defect.

Purpose The use of resorbable plates and screws for fixation of pediatric facial fractures is both well tolerated and effective. It enables realignment and stable positioning of rapidly healing fracture segments while obviating any future issues secondary to long-term metal retention. Patients and methods Forty-four pediatric facial fractures were treated over a 10-year period at our institution using differing techniques of polymeric bone fixation. Twenty-nine mandible fractures in patients under the age of 10 (age range, 6 months to 8 years) were treated. Displaced fractures of the symphysis, parasymphysis, body, and ramus underwent open reduction and either 1.5-mm or 2.0-mm plate and screw fixation in 14 patients. Subcondylar fractures were treated by a short period of maxillomandibular fixation (3 weeks) achieved with suture ligation between resorbable screws placed at the zygoma and symphysis or a circummandibular suture attached to a zygomatic screw. Fifteen patients (age range, 4 to 11 years) with isolated frontal, supraorbital, intraorbital, or orbitozygomatic fractures were treated by open reduction and internal fixation with 1.5-mm resorbable plates, mesh, and screws. Results No long-term implant-related complications were seen in any of the treated patients. Conclusions Resorbable polylactic and polyglycolic acid plates and screws can be an effective fixation method for facial fractures in children in the primary and secondary dentition periods.

Alloplastic cranioplasty techniques using polyfmethylmethacrylate (PMMA) are a common method of restoring lost cranial bone. Numerous compositions of PMMA exist for this application, using either intraoperatively cured solid compositions or preoperatively fabricated porous custom implants. Although all of these PMMA materials feel solid by palpation, the amount of cranial protection that they provide has never been precisely evaluated. Whether differences exist between the differing PMMA cranioplasty materials likewise is unknown. An impact resistance test was performed on uniform-size blocks of differing PMMA materials of representative cranial thickness using American Society of Testing and Materials (ASTM) method D 3029-78. Based on mean failure weights of 3.9 lb (Cranioplast), 4.2 lb (Cranioplexx), and 4.0 lb (HTR polymer), all of these materials are comparatively the same in impact resistance. Precured porous PMMA, despite having 30% to 40% less material, offered no less impact resistance. Based on projections to cranial bone, PMMA materials appear to offer protection similar to that of native osseous tissue.

Dog bite injuries to a child's face are not an infrequent occurrence. They may require primary and revisional surgery. All result in permanent facial scars. This report describes the treatment and outcomes of dog bites of the face, scalp, and neck based on a case series of 107 children over a 10-year period.The average children's age was 5.9 years. In cases where the dog was identified (95%), it was known to the victim and their family. The events leading to the dog bite were categorized as provoked (77%) in the majority of the cases.The majority of wounds could be closed primarily without a significant risk of wound infection. Complex reconstructions were required in more severe cases. The majority of families (77%) opted for scar revision between 9 and 18 months after initial treatment to improve the aesthetic outcome.Lawsuit actions resulted in 39 of the cases making good documentation an essential part of treatment. Dogbite injuries to the face in children frequently require multiple scar revisions to obtain the best possible aesthetic outcome, and the family should be so counseled at the onset of treatment.

Growth factors released from activated platelets initiate and modulate wound healing in both soft and hard tissues. A recent strategy to promote the wound-healing cascade is to prepare an autologous platelet concentrate suspended in plasma, also known as platelet-rich plasma, that contains growth factors and administer it to wound sites. The purpose of this study was to quantitate platelet number and growth factors released from a prepared platelet concentrate. Whole blood was drawn from 10 healthy patients undergoing cosmetic surgery and concentrated into platelet-rich plasma. Platelet counts on whole blood and platelet-rich plasma were determined using a Cell-Dyn 3200. Platelet-derived growth factor-BB, transforming growth factor-beta1, vascular endothelial growth factor, endothelial growth factor, and insulin-like growth factor-1 were measured in the platelet-rich plasma using the enzyme-linked immunosorbent assay method. In addition, platelet activation during the concentration procedure was analyzed by measuring P selectin values in blood serum. An 8-fold increase in platelet concentration was found in the platelet-rich plasma compared with that of whole blood (baseline whole blood, 197 +/- 42 x 10 platelets/microl; platelet concentrate, 1600 +/- 330 x 10 platelets/microl). The concentration of growth factors also increased with increasing platelet number. However, growth factor concentration varied from patient to patient. On average for the whole blood as compared with platelet-rich plasma, the platelet-derived growth factor-BB concentration increased from 3.3 +/- 0.9 ng/ml to 17 +/- 8 ng/ml, transforming growth factor-beta1 concentration increased from 35 +/- 8 ng/ml to 120 +/- 42 ng/ml, vascular endothelial growth factor concentration increased from 155 +/- 110 pg/ml to 955 +/- 1030 pg/ml, and endothelial growth factor concentration increased from 129 +/- 61 pg/ml to 470 +/- 320 pg/ml. No increase was found for insulin-like growth factor-1. In addition, no increase in platelet activation occurred during the concentration procedure as determined by the platelet surface receptor P selectin (45 +/- 16 pg/ml to 52 +/- 11 pg/ml, p = 0.65). In conclusion, a variety of potentially therapeutic growth factors were detected and released from the platelets in significant levels in platelet-rich plasma preparations. Sufficient concentrates and release of these growth factors through autologous platelet gels may be capable of expediting wound healing in a variety of as yet undetermined specific wound applications.

The need to provide rigid bony fixation in the surgical treatment of craniofacial deformities has inspired an on-going evolution of surgical innovations and implants. Because of the young age of many treated craniosynostosis patients and the unique pattern of cranial vault growth, the extensive implantation of metal devices is potentially problematic. The use of resorbable plate and screw devices offers all of the benefits of rigid fixation without many of their potential risks. Since the introduction of resorbable plate and screw devices in 1996, tens of thousands of craniofacial patients have received implants, but long-term results from a large series have yet to be reported. A combined prospective and retrospective analysis was done on 1883 craniosynostosis patients under 2 years of age treated by 12 surgeons from seven different geographic locations over a 5-year period who used the same type of resorbable bone fixation devices (poly-L-lacticpolyglycolic copolymer). Specifically, the incidence of postoperative infection, fixation device failure, occurrence of delayed foreign-body reactions, and the need for reoperation resulting from device-related problems were determined. Technical difficulties and trends in device use were also noted. From this series, significant infectious complications occurred in 0.2 percent, device instability primarily resulting from postoperative trauma occurred in 0.3 percent, and self-limiting local foreign-body reactions occurred in 0.7 percent of the treated patients. The overall reoperation rate attributable to identifiable device-related problems was 0.3 percent. Improved bony stability was gained by using the longest plate geometries/configurations possible and bone grafting any significant gaps across plated areas that were structurally important. The specific types of plates and screws used evolved over the study period from simple plates, meshes, and threaded screws to application-specific plates and threadless push screws whose use varied among the involved surgeons. This report documents the safety and long-term value of the use of resorbable (LactoSorb) plate and screw fixation in pediatric craniofacial surgery in the infant and young child. Device-related complications requiring reoperation occurred in less than 0.5 percent of the implanted patients, which is less frequent than is reported for metallic bone fixation. Resorbable bone fixation for the rapidly growing cranial vault has fewer potential complications than the traditional use of metal plates, screws, and wires.

A study of craniofacial bone distraction using an internal self-expanding bone device designed by the authors was performed in a young rabbit skull model. Ten 30-day-old New Zealand white rabbits were divided into two groups: 5 underwent distraction with the device, and 5 served as controls. Serial cephalograms, defleshed skull measurements, and histological examinations were performed on the study animals. The distracted group demonstrated a significant midface lengthening and overbite compared with the control group. Histologically, more fibroblasts and osteoblasts were seen in the front nasal bone in the distracted group in comparison with the nondistracted controls. The self-expanding internal bone distractor can effectively lengthen certain facial bones in an animal model and avoid some of the disadvantages associated with the external distraction techniques. This new device offers clinical potential as a useful distraction technique, but further work is needed to determine the effects of continuous postoperative tension loads on bone healing, the amount of tension generated by certain spring loads and lengths, and the feasibility of applying this concept in confined bone spaces.

A clinical series of 62 patients who underwent cranioplasty using a new quick-setting hydroxyapatite (HA) material was done over a 2-year period. The majority of procedures (69%) were performed for secondary reconstruction of frontal, temporal, and supraorbital deficiencies after primary repair of a craniosynostosis. The frontal sinus was obliterated as part of the cranioplastic procedure in 5 cases (8%) in older patients. The material set effectively in approximately 5 minutes with a good working time. Infection occurred in 3 patients (5%) which was treated by removing the HA cranioplastic material. This faster-setting HA material offers similar cranioplastic benefits as other materials but with an accelerated intraoperative set time.

Heat is one of the fundamental forces that influence the rates of chemical reactions. The hydrolysis of an absorbable polymer is a function of many factors, both material-related and implant-site-related, including temperature. There is variance in temperature among patients as well as among various animals in which degradation studies are performed. This study investigated the influence of temperature on hydrolysis and found that a variance from 37 degrees C to as little as 2 degrees C can affect the rate of hydrolysis of a PGA/PLLA copolymer about 25-30%, with the rate increasing with increasing temperature. As most animals of biomedical interest have a body temperature on the order of 1-3 degrees C greater than that of humans, it is possible that animal testing may be "worst case"; that is, strength loss may be accelerated in animals relative to that in human patients. Also, variation of body temperature within the human population may contribute to some variance in the rate of hydrolysis from person to person; however, other influences may minimize this effect and make it difficult to observe clinically.

The biophysical characteristics of a new formulation of hydroxyapatite (HA) for craniofacial applications having a rapid set time was evaluated in animals. Using a mature rabbit model, the material was applied in both cranial defects and as a geometrically shaped cranial onlay. Visual and histological assessment was done after 1 year of implantation. The material remained morphologically stable after 1 year, with complete preservation of its onlay shape and stable fill of the cranial defects. A significant osteoconductive response was seen with bone growth across the inner and outer surfaces of the inlays and along the sides of the onlays. No fibrovascular ingrowth or bony replacement of the material itself was evident as a result of the age of the study animals or the compact density of the material. This rapid-setting HA formulation offers similar favorable tissue responses as those of other longer setting HA materials.

This review of contemporary techniques in facial bone reconstruction is written from the perspective of its specific application to defects from benign or malignant tumor resection. These bone defects pose unique reconstructive considerations because of their frequently large size, exposure to the oral cavity and paranasal sinuses, and potentially compromised wound beds due to radiation or loss of soft tissue lining, or both. The role of vascularized bone flaps, allograft bone, metal plating techniques with advances in fixation biomaterial technology, and distraction osteogenesis is discussed for these facial bone defects.

The use of plates and screws composed of a resorbable copolymer of poly L -lactic acid and polyglycolic acid (LactoSorb) for the repair of a variety of midfacial fracture patterns (orbital, zygomatic, and maxillary) was performed in 127 patients. Other than technique variations in application for screw insertion and plate adaptation, no clinical differences were observed in intraoperative bone stability or postoperative long-term results from prior experience with traditional metal devices. No occurrences of postoperative infection; abnormal, prolonged, or delayed soft-tissue swelling; or maxillary sinusitis occurred in this series with a 1- to 7-year follow-up. Resorbable fixation devices work well in the midface when good bone stock is available and extensive comminution of important bony buttresses is not present. Their use requires certain conceptual and technical differences from metal fixation and these issues are highlighted in this clinical review.

Over a 7-year period, 23 pediatric mandible fractures were successfully treated with a variety of new treatment methods that employed resorbable plates and screws. Displaced fractures of the symphysis, parasymphysis, body, and ramus were treated by open reduction and plate fixation in 12 patients. Subcondylar fractures were treated by a short period of maxillomandibular fixation done by suture ligation between resorbable screws placed the zygoma and symphysis or a circummandibular ligature suspended to a zygomatic screw. All patients were successfully treated without complications.

The aim of this clinical series is to report the effectiveness and safety of using computer-generated alloplastic hard tissue replacement (HTR) implants for the reconstruction of large defects of the cranio-orbital region when combined with simultaneous bone tumor excision. Seven patients who had large nonmalignant bony lesions of the anterior cranial vault and orbit underwent simultaneous bony excision and reconstruction with preoperatively fabricated custom alloplastic implants. Preoperatively, a 3D computed tomography (CT) scan was obtained from which an anatomical model was fabricated. On the anatomical model, the predicted amount of bone excision was performed. The defect in the model was then used to create an alloplastic (HTR polymer) implant for reconstruction and surgical placement. At the time of surgery, the implant was secured into position with either metal or resorbable plates and screws. In cases where the frontal sinus was in proximity to the implant, it was either cranialized and covered with a pericranial flap or obliterated with hydroxyapatite cement. All computer-generated implants required some modification intraoperatively due to a larger amount of bony excision than was preoperatively planned. This was accomplished by modifying the sterile back-up of the implant as an addition to the original implant or completing reconstruction of the bony defect with hydroxyapatite cement. All patients have healed uneventfully with a minimum of 1 year follow-up (average, 2.6 years). In all cases, excellent contours have been maintained and all patients have remained infection-free. In the management of large benign bony tumors of the cranio-orbital region, simultaneous reconstruction with custom implants fabricated from porous, hydrophilic HTR polymer can be preoperatively fabricated based on an estimate of the subsequent bony defect. The successful use of this approach depends on a favorable tissue quality of the recipient site, a generous preoperative estimate of the amount of bone that will be resected so that the implant is adequate, intraoperative techniques of expanding the implant reconstruction, and intraoperative methods to assure a partitioning of the implant from the frontal sinus.

The aim of this clinical study was to evaluate the effectiveness and safety of using computer-generated alloplastic (hard-tissue replacement) implants for the reconstruction of large defects of the upper craniofacial region. Fourteen patients who had large (150 cm2) preexisting defects of the cranium or cranio-orbital region underwent surgical reconstruction. Preoperatively, a three-dimensional computed tomographic scan was obtained from which an anatomic model was fabricated. The defect in the model was then used to create an alloplastic (hard tissue-replacement polymer) implant for reconstruction and surgical placement. At the time of surgery, the implant was secured into position with either metal or resorbable fixation. In cases where the frontal sinus was in proximity to the implant, the frontal sinus was either cranialized and covered with a pericranial flap or obliterated with hydroxyapatite cement. In cases that had been previously irradiated or infected, wide bony debridement and coverage with a vascularized muscle was initially performed, followed by implant reconstruction 6 months later. All implants fit easily into the bone defects, and only four (29 percent) required some minor adjustments to complete the fit. All patients healed uneventfully. With a minimum of 1 year follow-up (average, 3 years) in all cases, excellent contours have been maintained and all patients have remained infection-free. In large cranial defects, custom implants fabricated from porous, hydrophilic hard-tissue replacement polymer provide an exacting anatomic fit and a solid stable reconstruction. This method of reconstruction in these defects is rapid and exact, and significantly reduces operative time. Critical attention must be paid, however, to management of the frontal sinus and preexisting bone infection and the quality of the overlying soft-tissue cover.

Improvements in surgical technique and an ever improving understanding of the embryologic and cellular origin of many congenital anomalies marks the gains made during the last decade in pediatric plastic surgery. This contemporary review highlights many of these advancements in the diverse array of birth and surgical defects.

The purpose of this experimental study was to determine whether acellular human dermis was capable of complete revascularization in a subcutaneous implantation site with various placement geometries. In young adult rabbit ears, four different sheet and rolled configurations were placed and harvested after 3, 7, 14, and 28 days with silicone rubber microangiographic injections followed by histologic analysis. Revascularization of single-layer acellular human dermis occurred rapidly and was essentially complete by 14 days after surgery. No differences were observed in the ingrowth of vessels regardless of how the basement membrane was oriented. In rolled configurations, vascular ingrowth throughout the implant was slower and had not completely penetrated the grafts by 28 days after surgery at study completion. Vessel ingrowth occurred through the implant surfaces contacting the surrounding soft tissue and along the open seam of the roll. No differences were seen whether the basement membrane was oriented on either the inside or the outside of the roll. Acellular human dermis is capable of significant revascularization of its compact collagen composition in the early postoperative period. In thicker geometries, the rate and completeness of vessel ingrowth are predictably slower. Whether complete revascularization of multilayered or rolled grafts is achieved cannot be determined from this study.

Advances in medical technology continue to present clinicians with new treatment options for their patients. Frequently, however, a "settling-in" period occurs after initial introduction, during which continued use and experience present new considerations. Absorbable internal fixation has been available in the orthopedic arena for more than a decade, but has been widely available in the craniomaxillofacial arena for only the past few years. Although the major considerations governing its use were obvious initially, since then a set of essential paradigms has presented itself. The authors summarize these principles, providing numerous clinical examples, with the goal of illustrating the current potential of this technology as well as establishing a baseline from which future developments can issue.

The use of nonmetallic plate and screw fixation composed of a resorbable copolymer of poly L-lactic acid and polyglycolic acid (LactoSorb) for the repair of isolated malar fractures was studied in 53 patients. Other than technique variations in application for screw insertion and plate adaptation, no clinical differences were observed in intraoperative bone stability or postoperative long-term results from prior experience with traditional metal devices. No occurrences of postoperative infection, soft-tissue swelling, or maxillary sinusitis occurred in this series with a 6-month to 2-year follow-up.

Background: Although autogenous soft tissue graft materials, such as fat, fascia, and dermis, are commonly used for subdermal and subcutaneous augmentation, their inherent disadvantages continue to inspire a search for an alternative biomaterial. Objective: This study investigated revascularization after subcutaneous implantation of Alloderm, an allograft derived from acellular human dermis, in a rabbit model. Methods: Alloderm was implanted under the skin in the ears of 8 adult female white rabbits. Harvesting took place after 3, 7, 14, and 28 days. Serial sections were stained and examined under light microscopy to assess vascular ingrowth, as determined by the number of vessels and their location of entry. Results: Postoperatively, minimal vessel ingrowth extending from all sides of the implantation site was visible in the grafts at 3 days. By 7 days, scattered vessels could be seen within the collagen bundles of the grafts. Further vessel ingrowth with nearly complete through-and-through vascularity was evident at 14 days. By 28 days, single-layer grafts were structurally intact, with identifiable vessels throughout the collagen bundles and no volume loss. Conclusions: Acellular human dermis is capable of complete revascularization within weeks after implantation. The orientation of the basement membrane has no impact on vascular ingrowth. The extent of revascularization in more complex grafts awaits further study.

Distraction osteogenesis of bone-grafted mandibles has been shown to occur without undue difficulties in bone regeneration and healing. In the patient with hemifacial microsomia for which early costochondral graft reconstruction has been done, secondary distraction lengthening may still be needed eventually. It is important to assess preoperatively that the superior portion of the graft is properly positioned against the residual glenoid fossa to prevent excessive superior movement of the proximal mandibular segment during distraction. The case presented clearly illustrates this unique distraction phenomenon.

Overview Bone grafting of the alveolus is an essential step in the reconstruction of the orofacial cleft deformity. Secondary grafting with iliac marrow consistently produces trabecular bone to unify the maxilla and provide odontogenic support. It requires preoperative maxillary alignment, well designed mucoperiosteal flaps, and good oral hygiene to be optimally successful. Its high success rate currently makes it the preferred approach at most centers. Primary grafting with rib results in a unified maxilla, eliminates the oronasal fistula, and does not adversely affect midfacial growth. It assists in preventing maxillary segmental collapse, particularly in the bilateral cleft patient. Whether it can produce enough alveolar bone to support long-term odontogenic needs awaits further clinical documentation in the limited numbers of centers that routinely perform this procedure.

Purpose: This study evaluated the capability and effectiveness of resorbable bone fixation devices in genioplasty surgery. Materials and Methods: Twenty patients underwent different genial movements that were stabilized with either 2.5-mm polylactic-polyglycolic acid lag screws or 2.0-mm polylactic-polyglycolic acid plates and screws. Results: Twenty-one anterior mandibular osteotomies were performed in 20 patients. Sixteen patients had advancement (80%), 2 had horizontal setback (10%), and 2 had vertical reduction (10%). The average advancement was 7.6 mm (range, 4 to 14 mm), the average horizontal setback was 6.0 mm (range, 4 to 8 mm), and the average vertical reduction was 7.0 mm (range, 5 to 9 mm). Fixation was done using the lag screw technique in 13 patients (65%) and plate and screw fixation in 7 patients. (35%) Intraoperative stability was satisfactory in all cases. There were no postoperative infections or segmental instability up to 6 months after surgery. Conclusion: Resorbable polylactic-polyglycolic acid lag screw and plate and screw fixation is a viable alternative for fixation of anterior horizontal osteotomies of the mandible.

A variety of ear defects can occur after resection of malignant tumors, which presents the option for a diverse array of surgical techniques for their reconstruction. Because the functional demands of the ear are few and the opposite ear is usually unaffected, reconstruction should focus on the position, size, and cotour of the resected ear. In skin-only defects, secondary healing, skin grafts, and direct closure are effective options. In smaller partial-and full-thickness defects, staged local and regional flaps with cartilage grafts can recreate the shape and contour of the ear. In total-ear defects, osseointegrated mastoid implants for prosthetic retention offer the most effective and rapid method for ear replacement. All of these reconstructive techniques are outlined and the indications for their use discussed.

The purpose of this study was to evaluate the intraoperative placement and clinical effectiveness of resorbable copolymeric screws for mandibular sagittal split ramus osteotomies. Thirty-seven patients who underwent bilateral sagittal split osteotomies of the mandible were fixated with three 2.5-mm copolymeric poly-L-lactic-polyglycolic (PLLA-PGA) screws on each side. No postoperative maxillomandibular fixation was applied. Twenty-five patients experienced mandibular advancement and 12 patients had setbacks. The average advancement was 6.5 mm (range, 3-17 mm) and the average set-back was 5.2 mm (range, 3-8 mm). Intraoperative placement was uncomplicated and no screws were stripped during placement. No problems in immediate postoperative stability were encountered and relapse was not evident in any patient. Follow-up ranged from 3 to 17 months. The screw holes remained evident radiographically after 1 year. Two and one-half-millimeter copolymeric PLLA-PGA resorbable screws for mandibular ramus osteotomies appear to offer clinical results comparable with metallic screw fixation.

The use of three-dimensional, computer-generated anatomic models can be used in the diagnosis and reconstruction of a variety of craniofacial problems. They are readily manufactured from computed tomography scans at a reasonable cost with only several weeks of preparation and delivery time. Their contemporary value is in the preoperative treatment planning, intraoperative implant fashioning, and preoperative implant fabrication in appropriately selected patients.

The use of nonmetallic rigid fixation (plate and screws) composed of resorbable polymers (poly L-lactic acid and polyglycolic acid) for the repair of isolated maxillary (LeFort I) fractures was studied in 11 patients. Provided good bone (noncommi-nuted) was available for fixation placement, no differences were observed in intraoperative maxillary stability or long-term postoperative results.

A skeletal fixation system employing plates made of polylactic and polyglycolic acid has been employed at Indiana University Medical Center since July 1993 in 105 craniofacial reconstructions, 45 cases of maxillofacial trauma, 10 craniotomy flap repairs, and five cases involving reconstruction of the laryngotrachea. Because these plates eventually resorb, they offer significant theoretical advantages. No inhibition of structural growth should occur when using this system in children. Tissue tolerance of these plates has been excellent. The technical details of using heat to allow reshaping of the plates as well as the methods of fixation of the plates are discussed.

The advent of microsurgical technique has relegated nonvascularized methods of mandibular reconstruction to a less significant role than they occupied only 10 years ago. In properly selected patients, however, free autogenous bone grafts and alloplastic implants still offer reconstruction options that can be both reliable and effective. The single most important factor in deciding between vascularized and nonvascularized mandible reconstruction is the tissue characteristics of the recipient site. Previous irradiation, lack of adequate intraoral lining or cutaneous cover, bone sites with osteomyelitis or osteoradionecrosis, or tissue beds with extensive scarring caused by previous surgery or trauma bode poorly for nonvascularized techniques. The adjunctive use of pre- and postoperative hyperbaric oxygen may permit nonvascularized bone grafting to be effective in these compromised wound beds. In mandibular resection sites with unimpaired wound healing, a variety of nonvascularizedtechniques are described, which are useful particularly in lateral body and ramus defects. In patients with limited life expectancy, alloplastic metal implants alone can restore acceptable form and function, even in less optimal tissue beds.

Biomechanical tests of torsional loading and cantilevered bending were used to study the effects of varying screw size and design of five different titanium miniscrews and microscrews in a metacarpal spiral oblique fracture model. Sixty-six fresh frozen human cadaveric metacarpal bones were subjected to torsional loading until failure, producing a spiral oblique fracture. The randomized fractured metacarpal bones were then repaired utilizing two 1.2-mm, 1.7-mm, or 2.3-mm self-tapping Leibinger lag screws ; and 1.5-mm or 2.0-mm pretapped Synthes lag screws. Following repair, the specimens were then subjected to cantilevered bending or torsional loading. Failure torque and bending loads were then used to calculate failure stresses at the midshaft for torsional loading or at the proximal screw for cantilevered bending. Analysis of variance statistical analysis revealed that within the cortical thickness of bone studied, no significant difference in shear stress or axial stress was observed with increasing screw diameter and screw design.

A case report is presented on the utilization of an acellular dermal matrix in the formation of a biologic silo conducive to early epithelial grafting in the treatment of a giant omphalocele associated with cloacal exstrophy.

The use of resorbable bone fixation devices composed of a copolymer of polyglycolic acid and polylactic acid were investigated in an animal model as well as in human application. We used resorbable plates and metallic microscrews in immature rabbits; plating of the coronal suture resulted in complete device resorption and increased interscrew distances (i.e., growth across the suture) after 8 postoperative months. In 20 infants with calvarial deformities, thin, straight resorbable plates were used for skeletal fixation after osteotomies and repositioning. A total of 231 fixation devices were implanted without complications after 12 postoperative months. These encouraging results have led to further clinical application in craniosynostosis deformities.