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1.
Ann Plast Surg ; 91(6): 758-762, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856194

RESUMO

PURPOSE: Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by painful and foul-smelling cystic nodules and sinus tracts in the apocrine gland-bearing regions. The treatment options include topical, intralesional, systemic, and surgical modalities. Currently, the most novel therapy is laser therapy to provide localized treatment without systemic adverse effects. However, data regarding patient outcomes after laser treatment are limited because of the low prevalence of this disease. This study aimed to evaluate the efficacy of laser therapy as a treatment modality for patients with HS. METHODS: A retrospective review cohort analysis of patients with HS undergoing laser treatment between 2016 and 2021 was conducted. Patient demographics, lesion location(s), Hurley stage, age of onset and diagnosis, treatment length, type, outcomes, and complications were analyzed. RESULTS: Ninety-four patients met the inclusion criteria; on average, patients were treated with 5.8 laser sessions for 14.8 months with no complications and minor blood loss. Hidradenitis suppurativa progression commonly starts during puberty, with a median onset of 13.8 years and diagnosis of HS at 16.2 years. All patients (n = 94) showed an improvement in HS disease severity: 59.6% completed treatment, 12.0% are currently undergoing treatment, and 26.0% were lost to follow-up. CONCLUSIONS: Laser therapy is an effective and safe therapy for HS leading to improved quality of life and should be considered in the treatment and management of HS.


Assuntos
Hidradenite Supurativa , Terapia a Laser , Terapia com Luz de Baixa Intensidade , Humanos , Hidradenite Supurativa/cirurgia , Estudos Retrospectivos , Qualidade de Vida , Terapia com Luz de Baixa Intensidade/efeitos adversos , Índice de Gravidade de Doença
2.
Ann Plast Surg ; 80(6S Suppl 6): S352-S355, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29401128

RESUMO

BACKGROUND: The goal of cleft lip repair is a symmetrical balanced lip with minimal scar. Fat grafting is an established procedure in cosmetic and reconstructive surgery for restoration or correction of contour deformity, volume loss, and improved tissue characteristics. In this study, we evaluated the use of fat grafting in correction of cleft lip volume asymmetry. METHODS: We performed a retrospective analysis of our series of patients who underwent fat grafting using the Coleman technique for cleft lip volume asymmetry. Sex, age at primary repair, age at fat grafting, perioperative data, and preoperative and postoperative photographs were reviewed. RESULTS: A total of 52 children underwent fat grafting as secondary revision for both unilateral and bilateral cleft lip repair. Fat was hand suctioned from the abdominal or buttock region with a mean yield of 3.0 mL (range, 2.0-5.0 mL). An average total volume of 3.0 mL (range, 2.0-4.5 mL) of fat was injected via an intraoral incision into the philtrum, vermillion, and volume deficiencies in the vertical component of the lip for volume restoration. No complications were noted with fat harvest or with fat grafting. Mean follow-up was 48 months. Postoperative assessment revealed improved volume symmetry in all patients, and all patients or families were pleased with the results. CONCLUSIONS: Fat grafting via an intraoral incision is a minimally invasive, safe, and reliable secondary procedure to improve volume asymmetries after cleft lip repairs.


Assuntos
Fenda Labial/cirurgia , Assimetria Facial/cirurgia , Lábio/cirurgia , Lipectomia , Procedimentos de Cirurgia Plástica/métodos , Gordura Subcutânea/transplante , Adolescente , Criança , Pré-Escolar , Fenda Labial/complicações , Fenda Labial/patologia , Assimetria Facial/etiologia , Feminino , Seguimentos , Humanos , Lábio/anormalidades , Lipectomia/instrumentação , Lipectomia/métodos , Masculino , Procedimentos de Cirurgia Plástica/instrumentação , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento
3.
Cell Tissue Res ; 340(2): 323-33, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20309582

RESUMO

Multipotent stem cells derived from periodontal ligaments (PDLSC) and pulp of human exfoliated deciduous teeth (SHED) represent promising cell sources for bone regeneration. Recent studies have demonstrated that retinoic acid (RA) and dexamethasone (Dex) induce osteogenesis of postnatal stem cells. The objective of this study was to examine the effects of RA and Dex on the proliferation and osteogenic differentiation of SHED and PDLSC and to compare the osteogenic characteristics of SHED and PDLSC under RA treatment. SHED and PDLSC were treated with serum-free medium either alone or supplemented with RA or Dex for 21 days. The proliferation of SHED and PDLSC was significantly inhibited by both RA and Dex. RA significantly upregulated gene expression and the activity of alkaline phosphatase in SHED and PDLSC. Positive Alizarin red and von Kossa staining of calcium deposition was seen on the RA-treated SHED and PDLSC after 21 days of culture. The influences of RA on the osteogenic differentiation of SHED and PDLSC were significantly stronger than with Dex. Supplementation with insulin enhanced RA-induced osteogenic differentiation of SHED. Thus, RA is an effective inducer of osteogenic differentiation of SHED and PDLSC, whereas RA treatment in combination with insulin supplementation might be a better option for inducing osteogenic differentiation. Significantly higher cell proliferation of PDLSC results in greater calcium deposition after 3-week culture, suggesting that PDLSC is a better osteogenic stem cell source. This study provides valuable information for efficiently producing osteogenically differentiated SHED or PDLSC for in vivo bone regeneration.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Osteogênese , Ligamento Periodontal/citologia , Células-Tronco/citologia , Dente Decíduo/citologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Western Blotting , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/genética , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dexametasona/farmacologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Tretinoína/farmacologia
4.
J Craniofac Surg ; 18(2): 336-46; discussion 347-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17414283

RESUMO

Postoperative resynostosis and secondary craniofacial growth abnormalities are common sequelae after craniofacial surgery. It has been suggested that an overexpression of transforming growth factor-beta2 (Tgf-beta2) may be related to craniosynostosis and contribute to postoperative resynostosis. Interference with Tgf-beta2 function using neutralizing antibodies may inhibit resynostosis and improve postoperative craniofacial growth; the present study was designed to test this hypothesis. Twenty-nine New Zealand white rabbits with bilateral coronal suture synostosis were used: 1) suturectomy controls (n=9); 2) suturectomy with nonspecific, control IgG antibody (n=9); and 3) suturectomy with anti-Tgf-beta2 antibody (n=11). At 10 days of age, a 3 mm x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with 0.1 cc of a slow resorbing collagen gel mixed with either IgG (100 microg/suture) or anti-Tgf-beta2 (100 microg/suture). Three-dimensional computed tomography scan reconstructions of the skulls and cephalographs were obtained at 10, 25, 42, and 84 days of age. Computed tomography scan data revealed patent suturectomy sites and significantly (P<0.05) greater intracranial volumes by 84 days of age in rabbits treated with anti-Tgf-beta2 compared with controls. Cephalometric analysis revealed significant (P<0.05) differences in craniofacial, cranial vault, and cranial base growth by 84 days of age in rabbits treated with anti-Tgf-beta2 compared with controls. These data support the initial hypothesis that interference with Tgf-beta2 function inhibited postoperative resynostosis and improved cranial vault growth in this rabbit model. Thus, this biologically based therapy may be a potential surgical adjunct in the treatment of infants with craniosynostosis.


Assuntos
Anticorpos/uso terapêutico , Craniossinostoses/prevenção & controle , Craniossinostoses/cirurgia , Fatores Imunológicos/uso terapêutico , Fator de Crescimento Transformador beta2/antagonistas & inibidores , Análise de Variância , Animais , Encéfalo/crescimento & desenvolvimento , Cefalometria , Craniossinostoses/etiologia , Craniotomia/efeitos adversos , Cuidados Pós-Operatórios , Coelhos , Distribuição Aleatória , Prevenção Secundária , Crânio/crescimento & desenvolvimento , Tomografia Computadorizada por Raios X
5.
Cleft Palate Craniofac J ; 43(2): 244-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16526931

RESUMO

OBJECTIVE: This report describes an interesting case providing a brief review of the literature and highlighting the complexity in management and definitive treatment of a premature neonate with an obstructive epignathus teratoma and polydactyly bilaterally. Additionally, this case is unique because of the extremely large size of the oral tumor in relation to the neonate's total body size.


Assuntos
Doenças Fetais/diagnóstico , Neoplasias Maxilares/diagnóstico , Neoplasias Palatinas/diagnóstico , Diagnóstico Pré-Natal , Teratoma/diagnóstico , Feminino , Doenças Fetais/patologia , Dedos/anormalidades , Humanos , Recém-Nascido , Masculino , Neoplasias Maxilares/patologia , Neoplasias Maxilares/cirurgia , Neoplasias Palatinas/patologia , Neoplasias Palatinas/cirurgia , Polidactilia , Gravidez , Nascimento Prematuro , Teratoma/patologia , Teratoma/cirurgia
6.
Cleft Palate Craniofac J ; 42(4): 333-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16001911

RESUMO

OBJECTIVE: To present the first clinical use of a new bioabsorbable material, poly (D,L) lactic acid (PDLLA), in pediatric cranial-vault remodeling procedures. This discussion will highlight the benefits and detriments of PDLLA in comparison with currently used absorbable plating systems. DESIGN: This was a case study documenting the first North American case in which PDLLA was used to treat craniosynostosis. MATERIALS AND METHODS: Evaluation of pure PDLLA, a copolymer product of the mixture of poly L-lactic acid and its D-isomer, was used in an 8-month-old boy with a severe phenotypic expression of sagittal craniosynostosis. No signs of elevated intracranial pressure were present, and the neurological examination did not show impairments. Total cranial-vault remodeling with the "hung-span" technique was performed. The Resorb X system, containing 2.2-mm screws and 0.6- to 1-mm-thick plates, was used to stabilize the reconstructed cranial vault. RESULTS: No surgical complications occurred. The preoperative cranial index measured 62. The scaphocephalic appearance of the skull was eliminated, and the cranial index was normalized to 77. The screws and plates were less palpable than other plating systems. Twelve months postoperatively, none of the plates and screws were identifiable by external palpation. CONCLUSION: Resorb X has been successfully used in the treatment of sagittal craniosynostosis. Its rapid rate of resorption and lower profile make it an advantageous system for pediatric skull reconstruction. This represents the first use of this product in the United States for any pathology.


Assuntos
Implantes Absorvíveis , Placas Ósseas , Suturas Cranianas/cirurgia , Craniossinostoses/cirurgia , Craniotomia/métodos , Poliésteres/uso terapêutico , Parafusos Ósseos , Humanos , Lactente , Masculino
8.
Pediatr Dent ; 25(3): 253-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12889702

RESUMO

The alignment of the alveolar segments creates the foundation upon which excellent results of lip and primary nasal surgery are dependent in the repair of the cleft lip and palate patient. The purpose of this article is to illustrate the step-by-step fabrication process of the nasoalveolar molding appliance used to direct growth of the alveolar ridge, lips, and nose in the presurgical treatment of cleft lip and palate. As a result of this appliance, the primary surgical repair of the nose and lip heals under minimal tension, thereby reducing scar formation and improving the esthetic result.


Assuntos
Fenda Labial/terapia , Fissura Palatina/terapia , Obturadores Palatinos , Desenho de Prótese , Processo Alveolar/crescimento & desenvolvimento , Humanos , Recém-Nascido , Lábio/crescimento & desenvolvimento , Nariz/anormalidades , Nariz/crescimento & desenvolvimento , Cuidados Pré-Operatórios , Stents
9.
FASEB J ; 17(10): 1352-4, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12759339

RESUMO

In contrast to adult cutaneous wound repair, early gestational fetal cutaneous wounds heal by a process of regeneration, resulting in little or no scarring. Previous studies indicate that down-regulation of HoxB13, a member of the highly conserved family of Hox transcription factors, occurs during fetal scarless wound healing. No down-regulation was noted in adult wounds. Here, we evaluate healing of adult cutaneous wounds in Hoxb13 knockout (KO) mice, hypothesizing that loss of Hoxb13 in adult skin should result in enhanced wound healing. Tensiometry was used to measure the tensile strength of incisional wounds over a 60-day time course; overall, Hoxb13 KO wounds are significantly stronger than wild-type (WT). Histological evaluation of incisional wounds shows that 7-day-old Hoxb13 KO wounds are significantly smaller and that 60-day-old Hoxb13 KO wounds exhibit a more normal collagen architecture compared with WT wounds. We also find that excisional wounds close at a faster rate in Hoxb13 KO mice. Biochemical and histochemical analyses show that Hoxb13 KO skin contains significantly elevated levels of hyaluronan. Because higher levels of hyaluronan and enhanced wound healing are characteristics of fetal skin, we conclude that loss of Hoxb13 produces a more "fetal-like" state in adult skin.


Assuntos
Proteínas de Homeodomínio/fisiologia , Ácido Hialurônico/biossíntese , Fenômenos Fisiológicos da Pele , Pele/metabolismo , Cicatrização , Animais , Derme/anatomia & histologia , Proteínas de Homeodomínio/genética , Cinética , Camundongos , Camundongos Knockout , Pele/anatomia & histologia
10.
World J Surg ; 27(1): 108-16, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12557046

RESUMO

Fetal surgery is finding ever-increasing applications. At present, fetal surgical techniques are used only to treat diseases associated with high mortality risk or severe morbidity if left untreated prior to birth. Yet as a discipline, in utero therapy is attractive to plastic surgeons because it affords the potential to (1) provide a scarless repair, (2) correct the primary deformity, (3) prevent secondary deformities, and (4) give the parents a "normal"-appearing child at birth. Each of these potential benefits is particularly important in patients with craniofacial anomalies. This article will both review the animal models that have been used to study the potential for intrauterine plastic surgery and provide a synopsis of the benefits that fetal therapy may provide in the treatment of selected craniofacial anomalies.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Craniossinostoses/cirurgia , Doenças Fetais/cirurgia , Animais , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Feminino , Doenças Fetais/diagnóstico , Humanos , Modelos Anatômicos , Gravidez , Diagnóstico Pré-Natal
11.
Plast Reconstr Surg ; 110(2): 515-22, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12142670

RESUMO

Craniosynostosis is characterized by premature fusion of the cranial sutures. At the molecular level, mutations in homeobox genes, transcription factors, and growth factor receptors have been implicated in the pathogenesis of this disorder, but the specific etiologic pathways have not yet been elucidated. To further study the molecular biology behind craniosynostosis, perisutural tissues in a unique rabbit model with congenital delayed-onset coronal craniosynostosis were examined for the presence of the hedgehog family of growth factors and their receptor, patched-1. Expression of desert hedgehog, Indian hedgehog, sonic hedgehog, and patched-1 was evaluated in four areas: suture, endosteum, periosteum, and osteocytes, using immuno-histochemistry (n = 8). Protein levels in affected animals were compared with protein levels in wild-type control rabbits (n = 8). Overall, sonic hedgehog, Indian hedgehog, and patched-1 protein levels were greater in affected animals. Specifically, areas of increased staining were seen along the bony interface of the endosteum and periosteum and in the osteocytes of the synostotic rabbits. Interestingly, in the suture, increased levels of Indian hedgehog and sonic hedgehog, but not patched-1, were seen. There was minimal expression of desert hedgehog in both rabbit types. The increased overall presence of hedgehog and patched-1 proteins in synostotic rabbits may be a reactive change to the disorder or part of the pathogenic process. Although the specific cause cannot be determined from the data, it is clear that the molecular milieu of the cranial sutures in synostotic rabbits is markedly different from that of wild-type rabbits.


Assuntos
Suturas Cranianas/patologia , Craniossinostoses/patologia , Proteínas de Membrana/análise , Transativadores/análise , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Proteínas Hedgehog , Técnicas Imunoenzimáticas , Masculino , Osteócitos/patologia , Receptores Patched , Periósteo/patologia , Gravidez , Coelhos , Receptores de Superfície Celular
12.
Plast Reconstr Surg ; 110(2): 523-32, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12142671

RESUMO

With the modern emphasis on minimally invasive therapies, the concept of distraction is being applied in the treatment of craniosynostosis. Although specific genetic mutations have been identified in craniosynostotic patients, changes in the gene expression induced by cranial distraction have not yet been explored. The effects of cranial distraction on hedgehog and patched-1 expression were evaluated in a rabbit model for craniosynostosis. Rabbits (n = 8) were divided into four groups: affected rabbits, wild-type rabbits, affected rabbits subject to cranial distraction, and wild-type rabbits subject to distraction. Perisutural tissue was examined using immunohistochemistry in four areas: suture, endosteum, periosteum, and osteocytes, for the expression of Indian hedgehog, sonic hedgehog, and desert hedgehog and their receptor, patched-1. Two experimental groups were compared: (1) wild-type before distraction to wild-type after distraction, and (2) synostotic before distraction to synostotic after distraction. Distraction produced several variable and interesting changes in hedgehog protein presence. In wild-type rabbits, the predominant effect was a mild decrease in Indian hedgehog levels. Sonic and desert hedgehog and patched-1 protein levels were unchanged. In synostotic rabbits, the predominant effect of distraction was to decrease Indian hedgehog, sonic hedgehog, and patched-1 protein levels. This was especially true in the periosteum and endosteum. Cranial distraction of normal and affected rabbits differentially changed both the expression levels and patterns of the hedgehog and patched-1 proteins in the cranial tissues examined. These results suggest that molecular and genetic parameters of distraction and bone response may be different in craniosynostotic individuals, which may influence treatment protocols in these patients.


Assuntos
Suturas Cranianas/patologia , Craniossinostoses/patologia , Proteínas de Membrana/análise , Osteogênese por Distração , Transativadores/análise , Animais , Animais Recém-Nascidos , Craniossinostoses/genética , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/fisiologia , Proteínas Hedgehog , Técnicas Imunoenzimáticas , Masculino , Proteínas de Membrana/genética , Osteócitos/patologia , Receptores Patched , Periósteo/patologia , Gravidez , Receptores de Superfície Celular , Transativadores/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-12087866

RESUMO

We are entering a new era of craniosynostosis repair. When detected early, endoscopic skull remodeling, combined with a postoperative external skull-molding device, gives an excellent long-standing reconstruction of the cranial skeleton. This technique diminishes the morbidity of the operation and decreases the overall cost. It does not replace classic plate and screw cranial vault reconstruction in the older patient but is a useful weapon in the armamentarium of the craniofacial surgeon for the treatment of craniosynostosis in the neonatal period.


Assuntos
Craniossinostoses/cirurgia , Endoscopia , Fatores Etários , Perda Sanguínea Cirúrgica/prevenção & controle , Cefalometria/economia , Cefalometria/métodos , Suturas Cranianas/cirurgia , Dissecação , Endoscopia/economia , Desenho de Equipamento , Dispositivos de Proteção da Cabeça/economia , Custos de Cuidados de Saúde , Hospitalização , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Osso Parietal/cirurgia , Procedimentos de Cirurgia Plástica/economia , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/métodos , Crânio/crescimento & desenvolvimento , Fatores de Tempo
14.
Plast Reconstr Surg ; 109(6): 1819-25; discussion 1826-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11994578

RESUMO

A long-term follow-up study of patients who underwent bilateral mandibular distraction is presented, and the results of patients with Treacher Collins syndrome and Nager syndrome are compared with results for other forms of congenital micrognathia. It was hypothesized that the factors responsible for the predetermined, syndrome-specific shape of the mandible in patients with Treacher Collins and Nager syndromes would alter the long-term results of linear (uniplanar) distraction of the mandible. Thus, over time, the mandibles would remodel to preoperative form while maintaining the increase in volume. To investigate this hypothesis, all patients treated with bilateral mandibular distraction who had at least 1.5 years of follow-up, including satisfactory cephalometric examinations, were retrospectively reviewed. Two groups were identified. Group 1 (n = 6) were Treacher Collins and Nager syndrome patients (ages, 2 to 13 years; mean, 5.2 years) and group 2 (n = 6) included other forms of bilateral, congenital micrognathia (ages, 1.5 to 19 years; mean, 8.4 years). Serial cephalometric measurements were recorded before distraction, after distraction, and at least 18 months after distraction. Mandibular mean linear distraction distance (as recorded on the device) averaged 24.5 mm in group 1 and 26.2 mm in group 2. In group 1, the antegonial angle (angle from the mandibular plane to the top of the antegonial notch) decreased after distraction by 3.8 degrees, and the antegonial notch height was reduced by 1.6 mm. The posttreatment morphologic change was modified significantly over time, with a 3.7-degree increase of the antegonial angle and a 1.2-mm deepening of the antegonial notch. In group 2, the immediate reduction in height of the antegonial notching was subtler; however, long-term recurrence of the antegonial notching was also observed. At the end of distraction, the mean group 1 gonial angle became 8 degrees more obtuse. In contrast, patients in group 2 developed a more acute angle (mean, 8 degrees). The mandibles of the Treacher Collins syndrome patients (group 1) maintained their more obtuse postdistraction gonial angle during the period of follow-up, whereas over time this change was reversed in group 2 patients. In conclusion, experience with bilateral mandibular distraction has demonstrated that long-term determination of mandibular form is more complex than either the amount of distraction or the direction of the distraction vector. The underlying genotype and the musculoskeletal milieu must be taken into account when planning distraction, as these factors tend to remodel the mandible into its preoperative shape over time, despite the fact that the increased mandibular volume and projection are maintained.


Assuntos
Mandíbula/cirurgia , Disostose Mandibulofacial/cirurgia , Osteogênese por Distração , Cefalometria , Protocolos Clínicos , Seguimentos , Humanos , Estudos Retrospectivos
16.
J Craniofac Surg ; 13(2): 205-11, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12000874

RESUMO

Distraction osteogenesis has evolved as a mainstream surgical technique for lengthening and augmentation of the hypoplastic mandible. As clinical experience accumulated, there developed the need to "mold" the bony regenerate to avoid the development of postdistraction malocclusion and to achieve the desired craniofacial form. Although the potential to mold the regenerate has important clinical implications, the safety and efficacy of such an acute manipulation of the bony regenerate form have not yet been investigated in the laboratory. The purpose of this study was to determine if the distraction regenerate could be molded and result in a bony union. Four adult female dogs underwent bilateral mandibular distraction with an external multiplanar device (Stryker, Osteonics). After a latency period of 5 days, the mandibles underwent linear (anteroposterior) and angular (superoinferior) distraction to produce an anterior open bite of approximately 30 degrees. At the conclusion of the distraction procedure, the distraction sites were molded to close the open bite. In two dogs, the maneuver was performed over 3 days by changing the angulation of the devices (gradual molding), and in the other two dogs, molding was achieved with a single movement (acute molding). In the latter, the distraction devices were adjusted and reapplied to allow for anatomical fixation during the consolidation period of 49 days. According to the research protocol, the mandibles were assessed serially by cephalograms and computed tomography (CT) scans. All dogs survived the study without complications. The bony regenerate was easily molded in both groups to close the surgically created open bite. After molding, all the regenerates showed CT scan evidence of solid bone (consolidation), which was classified as "extended" on the Hamanishi scale. After the dogs were killed and soft tissue was removed, the regenerate seemed to be robust on gross examination without any evidence of fibrous nonunion. In addition, histological study of the regenerate confirmed the bony union. The study demonstrates that the mandible can be successfully molded into a desired anatomical position immediately after distraction without producing a fibrous union. Furthermore, it has been demonstrated that the bony regenerate is sufficiently malleable before consolidation to undergo either acute or gradual angular molding without disturbing osteogenic potential. The ability to mold the regenerate without the fear of creating a fibrous union or destroying bony potential provides the surgeon the capability to optimize the dental occlusion and mandibular form as part of the distraction treatment process.


Assuntos
Mandíbula/cirurgia , Avanço Mandibular/métodos , Mordida Aberta/cirurgia , Osteogênese por Distração , Animais , Cães , Feminino
17.
Plast Reconstr Surg ; 109(3): 925-33; discussion 934-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11884810

RESUMO

Costochondral grafting for reconstruction of the Pruzansky type III mandible has given variable results. Lengthening of the rib graft by means of distraction had been advocated when subsequent growth of the grafted mandible is inadequate. This retrospective study reviews a series of patients with mandibular costochondral grafts who underwent subsequent distraction osteogenesis of the graft. A retrospective review identified two patient groups: group 1 consisted of individuals (n = 9) who underwent costochondral rib grafting of the mandible followed by distraction osteogenesis several months later at a rate of 1 mm/day. Group 2 consisted of patients with Pruzansky type II mandibles who had distraction osteogenesis without prior rib grafting (n = 9). The biomechanical parameters, orthodontic treatment regimens, and complications were examined versus patient age and quality of the rib graft. Distraction osteogenesis was successfully performed in six of the rib graft patients (group 1) and in all of the group 2 individuals. On the basis of the Haminishi scale, the computed tomographic scan appearance of the regenerate was classified as "standard or external" in six of the group 1 patients and as either "agenetic" or "pillar" (fibrous union) in the remaining three patients. In group 1, the average device was expanded 23 mm (range, 20 to 30 mm). Group 2 mandibular distraction results were all classified as either standard or external, and there was an average device expansion of 22.4 mm (range, 16 to 30 mm). The length of consolidation averaged 12.6 weeks in group 1, compared with 8.5 weeks in the traditional mandibular distraction patients (group 2). The mean shift of the dental midline to the contralateral side was 2.5 mm in group 1 versus 4.0 mm in group 2. Complex multiplanar and transport distractions were successfully performed on grafts of adequate bony volume. All four patients in group 1 with tracheostomies were successfully decannulated after consolidation. Rib graft distraction complications included pin tract infections in two patients, hardware failure with premature pin pullout in one patient, and evidence of fibrous nonunions in three young patients with single, diminutive rib grafts. In group 2, there were no distraction failures. Distraction osteogenesis can be successfully performed on costochondral rib grafts of the mandible; however, the complication rate is higher than in non-rib-graft patients. Performing the technique on older, more cooperative individuals seems to reduce this risk. In addition, placement of a double rib graft or an iliac bone graft of sufficient volume to create a neomandible with greater bone stock is an absolute requirement to decrease the risk of fibrous nonunion and provide a bone base of sufficient size for retention of the distraction device and manipulation of the regenerate.


Assuntos
Transplante Ósseo , Osteogênese por Distração/métodos , Costelas/transplante , Cartilagem/transplante , Pré-Escolar , Feminino , Humanos , Recém-Nascido , Estudos Retrospectivos
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