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1.
J Craniomaxillofac Surg ; 50(11): 817-824, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36376159

RESUMO

The aim of this study was the development of a statistical model for reliable prediction of Posterior Airway Space (PAS) changes in lateral cephalograms (LCR) of patients after bimaxillary orthognathic surgery. The LCRs of patients who underwent bimaxillary orthognathic surgery were retrospectively analyzed. The anteroposterior dimension of the PAS was measured at three levels in the pre-operative and postoperative LCR: On the nasopharyngeal (SPAS), oropharyngeal (MAS), and hypopharyngeal level (IAS). The data of 139 patients were collected. The following changes of the PAS were measured: in class II patients SPAS: 0.291 mm (SD = 2.570 mm); MAS: 2.444 mm (SD = 2.986 mm); IAS: 0.750 mm (SD = 3.017 mm); in class III patients SPAS: 1.377 mm (SD 3.212 mm); MAS: 0.962 (SD: = 3.135 mm); IAS: 0.370 mm (SD = 3.468 mm). Linear regression analysis showed for class II patients, a significant influence of mandibular movement on MAS (p = 0.049) and a significant effect of maxillary and mandibular movements on SPAS (p = 0.001) and MAS (p = 0.022) in class III patients. The other jaw displacements had no significant impact on the investigated PAS levels. While the presented method does not permit exact prediction of the dimension of the PAS, it is still an easily accessible method of orientation for the surgeon. The surgeon can initiate three-dimensional examinations to provide exact three-dimensional prediction based on this calculation.


Assuntos
Má Oclusão Classe III de Angle , Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Ortognáticos/métodos , Má Oclusão Classe III de Angle/cirurgia , Cefalometria/métodos , Faringe/diagnóstico por imagem , Modelos Teóricos
2.
Ann Anat ; 231: 151517, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32229241

RESUMO

PURPOSE: Periodontal ligament (PDL) cell cultures are classically maintained in serum-containing media. However, unwanted side-effects of these conditions on cellular and molecular characteristics demand a serum-free alternative. Even though these limitations are well known and efforts for the development of adequate serum-free alternatives have been made, these approaches for replacement remained unsuccessful so far. This study aimed at developing a well-defined, serum-free formulation supporting both isolation from tissue samples and efficient expansion of PDL cells. Here, of particular focus was the perpetuation of tissue-characteristic markers detectable in primary tissues and of stemness features. BASIC PROCEDURES: Primary PDL cell cultures from generally healthy human donors (n = 3) were maintained in basal media N2B27 and E6 together with different concentrations of growth and attachment factors. Cell proliferation was recorded via microscopy and WST assay. Gene expression of RUNX2, Periostin, ALP, CD73, CD90, CD105, CD45, SOX10 and SOX2 was compared to primary PDL explants via qRT-PCR. Immunocytochemistry was performed for anti-CD105, SSEA-3, CD271, HNK1. Serum-containing sDMEM medium served as control. MAIN FINDINGS: N2B27 medium substituted with 25 ng/mL EGF, 25 ng/mL IGF1, 0.5 mg/mL Fetuin plus gelatine coating (designated N2B27-PDLsf) emerged as potent serum-free formulation ensuring adequate culture isolation and expansion. Here, PDL primary tissue signature markers RUNX2 and Periostin remained stable in N2B27-PDLsf compared to controls (229.0-fold ±101.0 and 83.2-fold ±9.6 increase). Additionally, stemness markers ALP and CD105 were significantly upregulated on transcriptional, and CD105 and SOX2 on protein level. PRINCIPAL CONCLUSIONS: This investigation identified a novel serum-free medium for the isolation, and expansion of primary human PDL cells with constantly high proliferation rates. Here, purity and stemness properties are maintained. Thus, N2B27-PDLsf represents a valid replacement for serum-containing media in PDL cultures.


Assuntos
Biomarcadores/análise , Meios de Cultura Livres de Soro , Ligamento Periodontal/citologia , Fosfatase Alcalina/análise , Fosfatase Alcalina/genética , Análise de Variância , Moléculas de Adesão Celular/análise , Moléculas de Adesão Celular/genética , Proliferação de Células , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Subunidade alfa 1 de Fator de Ligação ao Core/genética , DNA Complementar/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Ligamento Periodontal/química , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação
3.
Odontology ; 108(4): 607-616, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32030565

RESUMO

The aim of this study was to analyse the effect of cold atmospheric plasma (CAP) on human osteoblast-like cells in vitro. Additionally, underlying intracellular mechanisms were to be studied. Human osteoblast-like (MG63) cells were exposed to CAP for 60 s. The effects of CAP on key molecules essential for the wound healing response were studied using real-time PCR, ELISA and immunocytochemistry. For studying intracellular signalling pathways, MAP kinase MEK 1/2 was blocked. Cell viability was analysed by an XTT assay and with an EVE automated cell counter. Cell migration was examined by an in vitro wound healing assay.CAP exposition on osteoblast-like cells caused a significant upregulation of interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor (TNF)α, cyclooxygenase (COX)2, collagen (COL) 1α, matrix metalloproteinase (MMP)1, Ki67, proliferating-cell-nuclear-antigen (PCNA) and chemokine ligand (CCL)2 mRNA expression at 1 day. Interestingly, after blocking of MAP kinase, CAP-induced upregulation of Ki67 was inhibited by 57%. Moreover, CAP treatment improved significantly osteoblast-like cell viability as compared to untreated cells at 1 day. Beneficial effect of CAP treatment was shown by an in vitro wound healing assay, displaying a significant faster wound closure. Our findings provide evidence that CAP exposure effects gene and protein regulation in human osteoblast-like cells. Furthermore, CAP treatment has a positive impact on wound closure in an in vitro setting and might improve existing concepts of hard tissue regeneration in the future.


Assuntos
Gases em Plasma , Movimento Celular , Colágeno , Humanos , Osteoblastos , Cicatrização
4.
J Craniomaxillofac Surg ; 45(5): 731-740, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28318921

RESUMO

OBJECTIVES: TGF-ß1 signaling modulates epithelial mesenchymal transitions (EMT) of head and neck squamous cell carcinoma (HNSCC). Bone marrow mesenchymal stromal cells (BMSC) are able to exert a regulating influence on the expression of markers of EMT in HNSCC cells. It was thus the aim of this study to test the hypothesis that TGF-ß1 modulates the interactions of tumor transition between BMSCs and HNSCC, affecting the expression of E-cadherin, Vimentin, Snail, Twist, MMP14 and beta-catenin. Furthermore, we analyzed alterations in the AKT-signaling of tumor and stroma cells. MATERIALS AND METHODS: BMSCs were isolated from iliac bone marrow aspirates and co-cultured in trans-well permeable membrane wells with tumor cells of the established HNSCC cell line PCI-13. Following the induction with TGF-ß1 under serum free conditions the expression of Vimentin and E-Cadherin was assessed via immunofluorescence. A quantitative RT-PCR analysis of tumor transition markers E-cadherin, Vimentin, Snail, Twist, MMP14 and beta-catenin was performed. Changes in AKT-Signaling were identified via protein analysis. RESULTS: In non-induced co-cultures, BMSC were able to suppress Vimentin in PCI-13 as a marker of tumor transition. In TGF-ß1 induced co-cultures PCI-13 significantly increased the expression of Vimentin, Twist, Snail, MMP14, GSK3a, PRAS40, 4E-BP1, and AMPKa compared to monolayer controls. TGF-ß1 co-cultured BMSC demonstrated a significant increase of Snail, PRAS40, mTOR, GSK3a/b, Bad, PDK1 and 4E-BP1. CONCLUSIONS: TGF-ß1 was able to attenuate the modulating influence of BMSC in co-culture and drive the co-culture towards a progressive tumor transition, affecting the expression of markers of EMT, AKT-Signaling and proliferative checkpoints.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Neoplasias Bucais/patologia , Fator de Crescimento Transformador beta1/farmacologia , Adolescente , Adulto , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Criança , Técnicas de Cocultura , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Pessoa de Meia-Idade , Neoplasias Bucais/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
5.
Int J Oral Maxillofac Surg ; 44(11): 1355-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26227860

RESUMO

The use of ultrasound to cut bone in oral and craniofacial surgery has increased. There is concern that the application of ultrasound to the craniofacial skeleton might represent a potential hazard to the inner ear because of sound transmission by bone conduction resulting in hearing trauma. Conventional and ultrasound osteotomies were performed on human specimens of temporal bone containing an intact middle and inner ear. The equivalent sound pressure was measured with a microphone at the round window, which had been calibrated with a bone conduction audiometer. Conventional osteotomy with a rose burr resulted in maximum sound pressures of 125dB(A) consisting of major frequency components at 2100, 7600, and 9300Hz. Ultrasound osteotomy resulted in maximum sound pressures of 122dB(A) and exhibited major frequency components at around 10kHz, 20kHz, and 26.5kHz. Ultrasound osteotomies have no acoustic advantage over conventional osteotomies. Both osteotomy techniques can produce noise-induced hearing trauma, especially when applied over longer durations of time. This appears to be more relevant for ultrasound osteotomies, because the bone cutting efficiency is usually poorer than in conventional osteotomies. Surgeons should consider the risk of noise-induced potential damage to the inner ear when selecting the method of osteotomy.


Assuntos
Orelha Interna/lesões , Ruído/efeitos adversos , Osteotomia/efeitos adversos , Osteotomia/métodos , Osso Temporal/cirurgia , Ultrassom , Condução Óssea , Calibragem , Humanos , Técnicas In Vitro
6.
Clin Oral Investig ; 19(5): 1121-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25346374

RESUMO

OBJECTIVES: Cancer progression is influenced by tumor microenvironment and communication of stromal cells and tumor cells. Interactions may enhance epithelial-mesenchymal transition (EMT) of tumor cells through signaling proteins such as Wnt/beta-catenin and matrix metalloproteinases (MMP), as well as loss of cellular integrity, which affects invasion, progression, and metastasis of head and neck squamous cell carcinoma (HNSCC). In this study, we are testing the hypothesis that interactions of human mesenchymal stromal cells (MSCs) with HNSCC might influence the expression of markers of EMT and tumor progression by co-culturing human MSC with the PCI-13 HNSCC line. MATERIALS AND METHODS: Pooled MSCs were derived from the iliac bone marrow of seven patients and co-cultured in transwell permeable membrane wells with tumor cells of the established HNSCC cell line PCI-13 (UICC: T3, N1, M0). MSCs were characterized through fluorescence-activated cell sorting (FACS) analysis. Expression of Wnt3, E-cadherin, beta-catenin, MMP14, cathepsin b, and ETS1 was assessed by quantitative RT-PCR. RESULTS: We were able to show that co-culture of MSCs and PCI-13 leads to a significantly reduced expression of Wnt3, MMP14, and beta-catenin compared to controls, whereas the expression of cathepsin b and ETS1 was not significantly different between co-cultures and controls. CONCLUSION: Our results suggest that the interaction between MSCs and PCI-13 may suppress EMT in cancer cells. CLINICAL RELEVANCE: The influence of MSCs can suppress the onset of EMT in HNSCC, affecting tumor progression and therapy.


Assuntos
Carcinoma de Células Escamosas/patologia , Transição Epitelial-Mesenquimal , Neoplasias de Cabeça e Pescoço/patologia , Células-Tronco Mesenquimais/fisiologia , Adolescente , Adulto , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Criança , Técnicas de Cocultura , Progressão da Doença , Citometria de Fluxo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Carcinoma de Células Escamosas de Cabeça e Pescoço
7.
Int J Oral Maxillofac Surg ; 36(12): 1146-52, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17822884

RESUMO

Most parents are emotionally traumatized when confronted by the birth of a baby with an orofacial cleft (OFC). Affected families may have to compensate for increased financial, social and personal impacts before primary treatment is completed. This study was conducted to identify factors influencing the quality of life (QoL) of families having young children with OFC. A self-administered questionnaire containing the impact on family scale was applied in 130 consecutive families having children with OFC aged between 6 and 24 months. The results were related to the type of cleft and the time of initial diagnosis using non-parametric tests and multivariate correlation analysis (P<0.05). In families having children with isolated cleft lip, financial and social impacts were reduced, but problems in coping were increased when compared to families with children having cleft lip and palate or isolated cleft palate. Total impact was highest in families having children with isolated cleft palate, probably due to later surgery for reconstruction. Prenatal diagnosis of OFC did not reduce the general impact on affected families, but increased the social impact. The relation of certain impacts to distinct types of cleft might allow more tailored support of affected families and improve their QoL.


Assuntos
Fenda Labial/psicologia , Fissura Palatina/psicologia , Família/psicologia , Qualidade de Vida/psicologia , Ultrassonografia Pré-Natal/psicologia , Adulto , Pré-Escolar , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Métodos Epidemiológicos , Pai/psicologia , Feminino , Humanos , Lactente , Masculino , Mães/psicologia , Gravidez
8.
Eur J Med Res ; 12(1): 13-20, 2007 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-17363353

RESUMO

The circulating hormonal form of human parathyroid hormone (hPTH-1-37) has been assessed in vitro as well as in vivo in the ovariectomized rat, a model for postmenopausal osteoporosis. In vitro, hPTH-1-37 induces a dose-dependent cAMP formation and increases vitality as well as alkaline phosphatase activity in UMR106 osteosarcoma cells. Differentiation and proliferation of osteoclasts in rat bone marrow-derived stem cell preparations are decreased. Daily hPTH-1-37 s.c. administration in ovariectomized rats for 60 days results in augmented formation of new bone, in amplified femural bone density, and in thickening of the calvaria.


Assuntos
Osteoporose Pós-Menopausa/tratamento farmacológico , Hormônio Paratireóideo/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Fosfatase Alcalina/metabolismo , Análise de Variância , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Humanos , Ovariectomia , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Radiografia , Ratos , Ratos Wistar , Crânio/efeitos dos fármacos , Crânio/crescimento & desenvolvimento
9.
Int J Oral Maxillofac Surg ; 36(1): 54-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16965899

RESUMO

The aim of this pilot study was to investigate the potential of calcium phosphate cement in the treatment of orbital wall defect fractures in an adult sheep model, and to compare this alloplastic material to autologous calvaria split-bone grafts. Clinical, volumetric and histological examinations were carried out of both reconstruction materials. The use of cement made intraoperative corrections easier to perform, and increased the precision of reconstruction of the orbital volume. This material also proved to be osseoconductive. The two materials were used successfully in combination. Regions of most intensive remodelling were the anterior orbital floor and the adjacent orbital rim. The preliminary results of this study demonstrate the potential of calcium phosphate cement as a useful biomaterial in the reconstruction of the anterior orbital region. Further animal and clinical trials are necessary to investigate its ability as a carrier for mediators where bone healing requires influence or support.


Assuntos
Cimentos Ósseos/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Órbita/cirurgia , Fraturas Orbitárias/cirurgia , Animais , Materiais Biocompatíveis/farmacologia , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Transplante Ósseo , Fosfatos de Cálcio/farmacologia , Feminino , Modelos Animais , Projetos Piloto , Procedimentos de Cirurgia Plástica/métodos , Ovinos , Cirurgia Assistida por Computador
10.
Mund Kiefer Gesichtschir ; 10(1): 56-62, 2006 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-16341680

RESUMO

BACKGROUND: The endovascular occlusion of symptomatic carotid cavernous fistulae (CCF) via the transfemoral approach is safe and effective. Due to anatomical variations or after unsuccessful transarterial therapy, a direct surgical approach to the superior ophthalmic vein (SOV) may be necessary. CASE REPORTS: In two patients with acute ophthalmologic symptoms coil occlusion of the CCF was performed after palpebral incision and cannulation of the SOV. RESULTS: In both patients preparation of the SOV was performed successfully and without complications. After coil embolization of the CCF both patients had complete resolution of symptoms within several weeks. During a follow-up of 12 months there were no recurrences, but both patients exhibited moderate blepharoptosis. CONCLUSION: Embolization of CCF via a surgically created approach is an effective procedure in selected cases when standard interventional treatment is not possible.


Assuntos
Fístula Carótido-Cavernosa/terapia , Embolização Terapêutica/métodos , Equipe de Assistência ao Paciente , Fístula Carótido-Cavernosa/diagnóstico por imagem , Angiografia Cerebral , Diagnóstico Diferencial , Exoftalmia/etiologia , Olho/irrigação sanguínea , Oftalmopatias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Oftálmica/diagnóstico por imagem , Veias , Transtornos da Visão/etiologia
11.
Int J Oral Maxillofac Surg ; 34(7): 715-21, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16157247

RESUMO

Aim of this study was to determine the success of implants that were inserted in patients with cleft of the lip, alveolus and palate (CLAP) and to identify prognosis-relevant factors. In a prospective evaluation, 75 implants inserted in combination with bone grafting at cleft sites of 45 patients were examined. The observation period extended 5.5 years in average (minimum 1.5, maximum 11.3 years). Implant success was evaluated clinically and radiographically and was compared to age- and gender-matched control groups. Statistic assessment included Kaplan-Meier survival analysis, Log rank tests and Cox regression analysis. In total, 10 implants were lost in 8 patients, resulting in an implant survival rate of 82.2% at the end of the observation period. Patient-related parameters of age, gender or type of cleft had no significant influence. The length of an implant was significantly related to an improved survival rate (P<0.01). Implant survival was less in CLAP patients when compared to implant insertions in a non-cleft control group, but improved when compared to patients with bone grafting for other indications. It is concluded that implants combined with bone grafting can offer a reliable alternative in patients with CLAP.


Assuntos
Aumento do Rebordo Alveolar/métodos , Fissura Palatina/reabilitação , Implantação Dentária Endóssea/métodos , Implantes Dentários , Adolescente , Adulto , Transplante Ósseo , Fenda Labial/reabilitação , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Estatísticas não Paramétricas , Análise de Sobrevida
12.
Int J Oral Maxillofac Surg ; 34(6): 590-3, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16053884

RESUMO

The aim of this report is to present preliminary results and experiences using an ultrasonic bone-cutting device in bilateral sagittal split osteotomies of the mandible (BSSRO) with particular attention to possible damages to the inferior alveolar nerve (IAN). Seven patients with class II or class III malocclusion were treated by BSSRO with a conventional combined orthognathic and surgical approach. The osteotomy was carried out using an ultrasonic bone-cutting device. Subjective neurosensory deficits of the inferior alveolar nerve were assessed on 14 sides. Compared to the conventional techniques using saws, chisels and burs, the use of the ultrasonic device was more time-consuming, but the osteotomies were carried out at a high level of precision. In addition, this procedure offered the advantage of a blood-free surgical field and thus provided good control of the surgical procedure. Subjective neurosensory disturbances of the IAN showed a continuous decrease from 57.1% (eight sides) 2 months after the surgical procedure to 14.3% (2 sides) after 5 months and to 7.1% 7 months after BSSRO. Within the seven patients of this pilot study associated neurosensory disturbances were low. A possible advantage in terms of nerve protection is subject to a prospective study.


Assuntos
Má Oclusão/cirurgia , Mandíbula/cirurgia , Procedimentos Cirúrgicos Bucais/instrumentação , Distúrbios Somatossensoriais/prevenção & controle , Ultrassom , Adolescente , Adulto , Traumatismos dos Nervos Cranianos/prevenção & controle , Feminino , Humanos , Masculino , Osteotomia/instrumentação , Projetos Piloto , Traumatismos do Nervo Trigêmeo
13.
Int J Oral Maxillofac Surg ; 34(3): 294-304, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15741039

RESUMO

The purpose of this study was to investigate the effect of platelet-rich-plasma (PRP) on cranial distraction osteogenesis. Standardized calvaria critical size defects (6 cm x 5 cm) were created in 16 adult female sheep. Bifocal cranial transport distraction osteogenesis with autogenous free calvaria bone grafts (2 cm x 4 cm) was performed at a rate of 1mm once daily to a total of 30 mm. The 16 sheep involved in the experiment were randomly divided into four groups, four animals in each: Group 1 (no PRP, latency 5 days); Group 2 (no PRP, latency 0 day), Group 3 (PRP, latency 5 days) and Group 4 (PRP, latency 0 day). After a consolidation phase of 6 weeks, the animals were sacrificed and specimens harvested for conventional radiological and 3D quantitative computer tomographic (3D-QCT) assessment. New bone was generated in the distraction zone in all groups. There were significantly (P < 0.05) higher densities in the proximal region of the distraction regenerate in Group 4 (PRP, latency 0 day) compared to Group 2. However, no significant differences in mean density of the total distraction regenerate were found, neither in volume of the bony regenerate between the experimental groups. This study showed that PRP only had an effect on bone regeneration if active distraction was started immediately after application of PRP in the distraction gap.


Assuntos
Plaquetas , Regeneração Óssea/efeitos dos fármacos , Osteogênese por Distração , Crânio/cirurgia , Análise de Variância , Animais , Transplante Ósseo , Feminino , Substâncias de Crescimento/farmacologia , Imageamento Tridimensional , Modelos Animais , Plasmaferese , Distribuição Aleatória , Ovinos , Carneiro Doméstico , Fatores de Tempo , Tomografia Computadorizada por Raios X
14.
Arch Orthop Trauma Surg ; 124(10): 665-74, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15602675

RESUMO

INTRODUCTION: Several investigations over the past few years have shown that the importance of preserving the blood supply of the transport disc during segmental distraction has been overestimated. It was clearly demonstrated that distraction osteogenesis by local bone transportation could be achieved even with free bone grafts. So far, there have been no systematic investigations into how different types of free bone grafts vary in their function and suitability as transport discs in segmental craniofacial distraction. The aim of this study was to develop criteria to aid the clinician in selecting the most suitable free bone graft for distraction purposes. MATERIALS AND METHODS: Under general anesthesia, calvarial defects measuring 6 x 5 cm were created in 12 adult black head sheep in order to reconstruct them by segmental distraction using two different types of bone grafts as transport discs. Group 1 (n=6) received autotopical membranous bone of the calvarium as the transport segment, while group 2 (n=6) received heterotopical enchondral material from the iliac crest. Distraction was started postoperatively after 5 days at 0.6 mm/day and continued for 7 weeks. After a further 6 weeks of consolidation, the animals were killed and specimens examined macroscopically, radiographically and histologically. RESULTS: The significantly better quality of bone regenerates of group 1 was clearly influenced by the significantly better stability of the transport disc's connection to the distraction device, the calvaria grafts showing better volume stability and better mechanical resistance during transport than the iliac bone. The influence of both types of bone grafts on the macro- and microstructure of the newly formed bone was clearly evident. The mineralization density of group 2 regenerates was significantly lower than that of group 1 specimens. CONCLUSION: High mechanical stability of the bone graft is a very important point to consider when selecting a free graft for use as transport disc in local bone transport, especially if transport is necessary over long distances.


Assuntos
Transplante Ósseo , Osteogênese por Distração , Crânio/cirurgia , Animais , Osteogênese por Distração/métodos , Ovinos , Crânio/diagnóstico por imagem , Crânio/patologia , Tomografia Computadorizada por Raios X
15.
Int J Oral Maxillofac Surg ; 33(6): 575-83, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15308258

RESUMO

Bifocal transport osteogenesis (BTO) is a promising technique for the reconstruction of extended osseous craniofacial defects. Aim of this study was to determine the potential of this technique related to various donor sites of the transport segment. In 10 adult sheep critical size defects of the calvaria were treated by gradual movement of a transport segment consisting either of autogenous regional free calvarial bone grafts (n=5) or autogenous illiac free bone grafts (n=5). Latency period was 5 days; the rate of distraction was 1mm per day and extended approximately 40 days. The consolidation period was 28 days. After harvesting, specimens were investigated by conventional radiography, CT-scans, histologically and by fluorescence. In both groups transport osteogenesis resulted in a complete closure of the critical size defect. Membranous bone formation and remodeling occurred during the entire period of distraction and consolidation. The volumes and thickness of newly formed bone at the defect site were increased significantly when calvarial bone grafts were used (P<0.05). Iliac bone grafts became progrediently smaller during distraction, while the volume of calvarial grafts remained relatively constant (P<0.05). In conclusion, transport segments consisting of calvarial and iliac bone resulted in a reliable closure of craniofacial critical size defects in adult organisms; the application of calvarial bone grafts resulted in an increased extend of bone formation.


Assuntos
Transplante Ósseo/métodos , Calo Ósseo/fisiologia , Osteogênese por Distração/métodos , Osteogênese/fisiologia , Crânio/cirurgia , Animais , Calo Ósseo/diagnóstico por imagem , Feminino , Ílio/cirurgia , Osteogênese por Distração/instrumentação , Ovinos , Carneiro Doméstico , Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Z Gastroenterol ; 40(7): 497-502, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12122597

RESUMO

Cancer of the proximal digestive tract is associated with tobacco smoke and ethanol exposure. The UDP-glucuronosyltransferase (UGT) 1A7 is a detoxifying enzyme capable of tobacco-borne carcinogen detoxification and cellular protection and has been implicated as a cancer risk gene. In this study, UGT1A7 expression is demonstrated in oral, esophageal, and gastric tissue, which are the principle sites of proximal digestive tract cancer. Genomic DNA from the blood of 76 patients with esophageal, orolaryngeal and gastric cancer as well as from 210 healthy blood donors was analysed for the presence of UGT1A7 polymorphisms by sequencing and temperature gradient gel electrophoresis. Wild type UGT1A7 alleles were equally distributed between controls (19 %) and cancer patients (22 %). However, the UGT1A7*3 allele combining W208R, N129K and R131K missense mutations and exhibiting substantially reduced carcinogen detoxification activity was significantly associated with proximal gastrointestinal cancer and identified as a risk allele present in 32 % of cancer patients and 19 % of controls (P = 0.0008, OR 2,02 (95 %-CI 1.33-3.07)). We identify the significant association of the UGT1A7*3 allele encoding a low catalytic activity protein as a risk gene in proximal digestive tract cancer and as a potential marker for cancer susceptibility.


Assuntos
Neoplasias Gastrointestinais/genética , Glucuronosiltransferase/genética , Polimorfismo Genético/genética , Adulto , Idoso , Alelos , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/genética , Feminino , Neoplasias Gastrointestinais/enzimologia , Marcadores Genéticos/genética , Predisposição Genética para Doença/genética , Humanos , Neoplasias Laríngeas/enzimologia , Neoplasias Laríngeas/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/enzimologia , Neoplasias Bucais/genética , Mutação de Sentido Incorreto , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética
17.
J Inherit Metab Dis ; 24(6): 648-56, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11768584

RESUMO

Core binding factor A1 (CBFA1/RUNX2) is a runt-like transcription factor essential for osteoblast differentiation. Haplotype insufficiency causes cleidocranial dysplasia (CCD), a syndrome featuring supernumerary tooth buds, delayed tooth eruption, patent fontanels, Wormian bones, short stature, dysplasia of the clavicles, growth retardation and hypoplasia of the distal phalanges. We identified novel CBFAI/RUNX2 mutations after PCR and direct sequencing of patient leukocyte DNA. In family 1 mother and son are affected by CCD. Both carry the missense mutation R190W (CGG > TGG). This nucleotide change introduced a BsmI restriction site, which was used to independently confirm the mutation. It was absent in healthy members of the family. Family 2, in which father and daughter are affected by CCD, shows a deletion of nucleotide C821. This deletion causes a frameshift mutation with premature stop after the insertion of 18 aberrant amino acids. Healthy family members did not have this mutation. The clavicular dysplasia was more pronounced with the R19OW mutation, while the bone density was markedly reduced in individuals with either mutation, suggesting a previously underemphasized increased risk for osteoporosis in CCD.


Assuntos
Displasia Cleidocraniana/genética , Proteínas de Ligação a DNA/genética , Mutação de Sentido Incorreto/genética , Proteínas Proto-Oncogênicas , Fatores de Transcrição/genética , Adolescente , Adulto , Densidade Óssea/genética , Subunidade alfa 2 de Fator de Ligação ao Core , Densitometria , Éxons/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/genética , Linhagem , Fatores de Risco
18.
Mund Kiefer Gesichtschir ; 4 Suppl 2: S485-9, 2000 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-11094521

RESUMO

With increasing age of an organism, the osseous regenerative potential is reduced. In osteoblast-like cell cultures, cells of older donors that would not proliferate under standard conditions start to proliferate and express a differentiated phenotype when supplemented with the supernatant of fetal osteoblast-like cultures. The aim of this study was an evaluation of the fetal supernatant actions in vivo. Rat calvaria-derived osteoblasts of fetal and 21-day-old donors were isolated enzymatically and cultured. Their osteoblastic phenotype was confirmed by the expression of typical osteoblast synthesis products. The supernatant of the cultures of each age group was collected and pooled. The supernatant was purified by HPLC and concentrated approximately ten times. Additionally, several age-dependent differences within the purified protein fractions were documented by MALDI. After resuspension, the purified supernatant proteins were transferred on a collagen carrier and implanted into critical size defects of the calvaria of adult Wistar rats. In a control group, the collagen carriers were implanted containing isotonic salt solution. After 2, 4, and 8 weeks, a radiographic and histologic analysis of the regeneration process was performed which revealed differences in the progress of mineralization. The methods used in this study might help to identify age-dependent differences regarding the osteoblastic synthesis of osteoanabolic peptides and their impact on the regeneration of osseous defects.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osteoblastos/metabolismo , Extratos de Tecidos/farmacologia , Fatores Etários , Animais , Feto , Peptídeos/farmacologia , Ratos , Ratos Wistar , Crânio/efeitos dos fármacos , Crânio/patologia
19.
Mund Kiefer Gesichtschir ; 4(5): 330-4, 2000 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-11092188

RESUMO

Malignant change in the epithelium of an odontogenic cyst and growth of an invasive squamous cell carcinoma is rare. The diagnosis of malignant disease is mostly only established by histological evaluation of excised tissue because the initial clinical appearance does not differ much from that of odontogenic cysts. The clinical course of one patient after removal of an impacted canine and adjacent cystic tissue is presented. Histological evaluation of the specimen led to diagnosis of a squamous cell carcinoma arising from the cystic epithelium. Partial resection of the maxilla was performed subsequently and 1 year postoperatively the patient was free from recurrence or metastasis. This case report underlines the importance of submitting any soft tissue excised in the treatment of odontogenic cysts to histologic evaluation.


Assuntos
Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Maxilares/patologia , Cistos Odontogênicos/patologia , Adulto , Humanos , Masculino , Mandíbula/patologia , Mandíbula/cirurgia
20.
Mund Kiefer Gesichtschir ; 3(5): 270-4, 1999 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-10540828

RESUMO

Georg Friedrich Stromeyer (1804-1876) is generally known as one of the founders of orthopedics and orthopedic surgery and also made many contributions to modern military medicine. Furthermore, every oral and maxillofacial surgeon in Germany knows him because of the "Stromeyer hook", which is used for elevation of zygomatic arch fractures. This special aspect as well as Stromeyer's biography is presented in this article from the history of medicine.


Assuntos
Instrumentos Cirúrgicos/história , Fraturas Zigomáticas/história , Epônimos , Alemanha , História do Século XIX , Humanos
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