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1.
Lasers Surg Med ; 53(3): 291-299, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32529785

RESUMO

BACKGROUND AND OBJECTIVE: To take major advantage of erbium-doped yttrium aluminium garnet (Er:YAG) lasers in osteotomy-like freedom of cutting geometries and high accuracy-the integration and miniaturization of the robot, laser, and navigation technology was tried and applied to minipigs. The investigators hypothesized laser osteotomy would render acceptable bone healing based on the intraoperative findings and postoperative cut surface analysis. STUDY DESIGN/MATERIALS AND METHODS: We designed and implemented a comparative bone-cutting surgery in the minipig mandible with a cold ablation robot-guided Er:YAG laser osteotome (CARLO) and a piezoelectric (PZE) osteotome. The sample was composed of different patterns of defects in the mandibles of six grown-up female Goettingen minipigs. The predictor variable was Er:YAG osteotomy and PZE osteotomy. The outcome variable was the cut surface characteristics and bone healing at 4 and 8 weeks postoperatively. Descriptive and qualitative comparison was executed. RESULTS: The sample was composed of four kinds of bone defects on both sides of the mandibles of six minipigs. We observed more bleeding during the operation, open-cut surfaces, and a faster healing pattern with the laser osteotomy. There was a possible association between the intraoperative findings, postoperative cut surface analysis, and the bone healing pattern. CONCLUSIONS: The results of this study suggest that characteristic open-cut surfaces could explain favorable bone healing after laser osteotomy. Future studies will focus on the quantification of the early healing characteristics after laser osteotomy, its diverse application, and the safety feature. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Robótica , Animais , Feminino , Lasers de Estado Sólido/uso terapêutico , Mandíbula/cirurgia , Osteotomia , Projetos Piloto , Suínos , Porco Miniatura
2.
Int J Mol Sci ; 22(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34445228

RESUMO

Recent advancements in medical imaging, virtual surgical planning (VSP), and three-dimensional (3D) printing have potentially changed how today's craniomaxillofacial surgeons use patient information for customized treatments. Over the years, polyetheretherketone (PEEK) has emerged as the biomaterial of choice to reconstruct craniofacial defects. With advancements in additive manufacturing (AM) systems, prospects for the point-of-care (POC) 3D printing of PEEK patient-specific implants (PSIs) have emerged. Consequently, investigating the clinical reliability of POC-manufactured PEEK implants has become a necessary endeavor. Therefore, this paper aims to provide a quantitative assessment of POC-manufactured, 3D-printed PEEK PSIs for cranial reconstruction through characterization of the geometrical, morphological, and biomechanical aspects of the in-hospital 3D-printed PEEK cranial implants. The study results revealed that the printed customized cranial implants had high dimensional accuracy and repeatability, displaying clinically acceptable morphologic similarity concerning fit and contours continuity. From a biomechanical standpoint, it was noticed that the tested implants had variable peak load values with discrete fracture patterns and failed at a mean (SD) peak load of 798.38 ± 211.45 N. In conclusion, the results of this preclinical study are in line with cranial implant expectations; however, specific attributes have scope for further improvements.


Assuntos
Benzofenonas , Sistemas Automatizados de Assistência Junto ao Leito , Polímeros , Impressão Tridimensional , Próteses e Implantes , Crânio/lesões , Humanos , Procedimentos de Cirurgia Plástica
4.
J Med Internet Res ; 21(8): e13003, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392963

RESUMO

BACKGROUND: Multiple sclerosis (MS) is a chronic neurological disease occurring mostly in women of childbearing age. Pregnant women with MS are usually excluded from clinical trials; as users of the internet, however, they are actively engaged in threads and forums on social media. Social media provides the potential to explore real-world patient experiences and concerns about the use of medicinal products during pregnancy and breastfeeding. OBJECTIVE: This study aimed to analyze the content of posts concerning pregnancy and use of medicines in online forums; thus, the study aimed to gain a thorough understanding of patients' experiences with MS medication. METHODS: Using the names of medicinal products as search terms, we collected posts from 21 publicly available pregnancy forums, which were accessed between March 2015 and March 2018. After the identification of relevant posts, we analyzed the content of each post using a content analysis technique and categorized the main topics that users discussed most frequently. RESULTS: We identified 6 main topics in 70 social media posts. These topics were as follows: (1) expressing personal experiences with MS medication use during the reproductive period (55/70, 80%), (2) seeking and sharing advice about the use of medicines (52/70, 74%), (3) progression of MS during and after pregnancy (35/70, 50%), (4) discussing concerns about MS medications during the reproductive period (35/70, 50%), (5) querying the possibility of breastfeeding while taking MS medications (30/70, 42%), and (6) commenting on communications with physicians (26/70, 37%). CONCLUSIONS: Overall, many pregnant women or women considering pregnancy shared profound uncertainties and specific concerns about taking medicines during the reproductive period. There is a significant need to provide advice and guidance to MS patients concerning the use of medicines in pregnancy and postpartum as well as during breastfeeding. Advice must be tailored to the circumstances of each patient and, of course, to the individual medicine. Information must be provided by a trusted source with relevant expertise and made publicly available.


Assuntos
Aleitamento Materno/métodos , Aprendizado de Máquina/normas , Esclerose Múltipla/tratamento farmacológico , Mídias Sociais/normas , Adulto , Feminino , Humanos , Gravidez , Medição de Risco
5.
J Craniofac Surg ; 30(6): 1877-1881, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31058722

RESUMO

PURPOSE: Several post-processing algorithms for 3D visualization of the skull in craniosynostosis with their specific advantages and disadvantages have been already described. The Finite Element Method (FEM) described herein can also be used to evaluate the efficacy of the cutting patterns with respect to an increase in the projected surface area under assumed uniform loading of the manipulated and cut bone segments. METHODS: The FEM analysis was performed. Starting with the classic cranial osteotomies for bifrontal craniotomy and orbital bandeau a virtually mirroring of the unaffected triangular shaped frontal bone was performed to achieve a cup-shaped sphere of constant thickness of 2.5 mm with a radius of 65 mm. Mechanical properties required for the analysis were Young's modulus of 340 MPa and Poisson's ratio of 0.22. Four different cutting patterns from straight to curved geometries have been projected onto the inner surface of the sphere with a cutting depth set to 2/3rds of the shell thickness. The necessary force for the deformation, the resulting tensions and the volume loss due to the osteotomy pattern were measured. RESULTS: Better outcomes were realized with pattern D. The necessary force was 73.6% smaller than the control group with 66N. Best stress distribution was achieved. Curved cutting patterns led to the highest peak of stress and thus to a higher risk of fracture. Straight bone cuts parallel to the corners or to the thighs of the sphere provided a better distribution of stresses with a small area with high stress. Additionally, also with pattern D a surface increase of 20.7% higher than reference was registered. CONCLUSION: As a proof of concept for different cutting geometries for skull molding in the correction of craniosynostosis, this computational model shows that depending of the cutting pattern different biomechanical behavior is achieved.


Assuntos
Craniossinostoses/cirurgia , Osteotomia , Algoritmos , Simulação por Computador , Módulo de Elasticidade , Análise de Elementos Finitos , Humanos , Rádio (Anatomia) , Estresse Mecânico
6.
Lasers Surg Med ; 47(5): 426-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25945815

RESUMO

BACKGROUND AND OBJECTIVES: Despite of the long history of medical application, laser ablation of bone tissue became successful only recently. Laser bone cutting is proven to have higher accuracy and to increase bone healing compared to conventional mechanical bone cutting. But the reason of subsequent better healing is not biologically explained yet. In this study we present our experience with an integrated miniaturized laser system mounted on a surgical lightweight robotic arm. STUDY DESIGN/MATERIALS AND METHODS: An Erbium-doped Yttrium Aluminium Garnet (Er:YAG) laser and a piezoelectric (PZE) osteotome were used for comparison. In six grown up female Göttingen minipigs, comparative surgical interventions were done on the edentulous mandibular ridge. Our laser system was used to create different shapes of bone defects on the left side of the mandible. On the contralateral side, similar bone defects were created by PZE osteotome. Small bone samples were harvested to compare the immediate post-operative cut surface. RESULTS: The analysis of the cut surface of the laser osteotomy and conventional mechanical osteotomy revealed an essential difference. The scanning electron microscopy (SEM) analysis showed biologically open cut surfaces from the laser osteotomy. The samples from PZE osteotomy showed a flattened tissue structure over the cut surface, resembling the "smear layer" from tooth preparation. CONCLUSIONS: We concluded that our new finding with the mechanical osteotomy suggests a biological explanation to the expected difference in subsequent bone healing. Our hypothesis is that the difference of surface characteristic yields to different bleeding pattern and subsequently results in different bone healing. The analyses of bone healing will support our hypothesis.


Assuntos
Terapia a Laser/instrumentação , Lasers de Estado Sólido/uso terapêutico , Mandíbula/cirurgia , Mandíbula/ultraestrutura , Osteotomia/instrumentação , Piezocirurgia/instrumentação , Animais , Feminino , Microscopia Eletrônica de Varredura , Suínos , Porco Miniatura
7.
BMC Med Ethics ; 16: 43, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26088562

RESUMO

BACKGROUND: Overtreatment (or unnecessary treatment) is when medical or dental services are provided with a higher volume or cost than is appropriate. This study aimed to investigate how a group of dentists in Switzerland, a wealthy country known to have high standards of healthcare including dentistry, evaluated the meaning of unnecessary treatments from an ethical perspective and, assessed the expected frequency of different possible behaviors among their peers. METHODS: A vignette describing a situation that is susceptible for overtreatment of a patient was presented to a group of dentists. The vignette was followed by five options. A questionnaire including the vignette was posted to 2482 dentists in the German-speaking areas of Switzerland. The respondents were asked to rate each option according to their estimation about its prevalence and their judgment about the degree to which the behavior is ethically sound. RESULTS: 732 completed questionnaires were returned. According to the responses, the most ethical and the most unethical options are considered to be the most and the least prevalent behaviors among dentists practicing in Switzerland, respectively. CONCLUSIONS: Suggesting unnecessary treatments to patients seems to be an ethically unacceptable conduct in the eyes of a sample of dentists in Switzerland. Although the respondents believed their colleagues were very likely to behave in an ethical way in response to a situation that is susceptible to overtreatment, they still seemed to be concerned about the prevalence of unethical behaviors in this regard.


Assuntos
Atitude do Pessoal de Saúde , Odontólogos/ética , Ética Odontológica , Padrões de Prática Odontológica/ética , Procedimentos Desnecessários/ética , Adulto , Feminino , Humanos , Masculino , Uso Excessivo dos Serviços de Saúde , Pessoa de Meia-Idade , Relações Médico-Paciente , Inquéritos e Questionários , Suíça
8.
Int J Comput Dent ; 18(4): 333-42, 2015.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-26734667

RESUMO

INTRODUCTION: The load-carrying behavior of the human mandible can be described using finite element simulation, enabling investigations about physiological and pathological skeletal adaption. "Anatomical simulation" implies a stepwise approximation towards the anatomical reality. METHOD: The project is structured in three steps. In Step 1, the preprocessing, the simulation model is provided. Step 2 is the numerical computation. Step 3 is dedicated to the interpretation of the results. The requirements of the preprocessing are: a) realization of the organ's individual anatomy, namely its outer shape; b) the tissue's elastic properties, thus its inner consistency; and c) the organ's mechanical loads. For physiological mandibular loading, these are due to muscles, temporomandibular joints, and tooth forces. Meanwhile, the reconstruction of the macroscopic anatomy from computed tomography data is standard. The periodontal ligament is inserted ex post using an approach developed by the authors. The bone is modeled anisotropically and inhomogeneously. By the visualization of the individual fiber course, the muscular force vectors are realized. The mandibular condyle is freely mobile in a kind of simplified joint capsule. For the realization of bite forces, several approaches are available. RESULTS: An extendible software tool is provided, enabling the user - by variable input of muscle and bite forces - to examine the individual patient's biomechanics, eg, the influence of the periodontal ligament, the condition of the temporomandibular joints, atrophic processes, or the biomechanical situation of dental implants. DISCUSSION: By stepwise approximation towards the anatomical reality, the mandibular simulation will be advanced to a valuable tool for diagnosis and prognosis.


Assuntos
Simulação por Computador , Análise de Elementos Finitos , Mandíbula/fisiologia , Modelos Biológicos , Anisotropia , Fenômenos Biomecânicos , Força de Mordida , Módulo de Elasticidade , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Mandíbula/anatomia & histologia , Músculos da Mastigação/fisiologia , Modelos Anatômicos , Planejamento de Assistência ao Paciente , Ligamento Periodontal/fisiologia , Software , Estresse Mecânico , Articulação Temporomandibular/fisiologia , Tomografia Computadorizada por Raios X/métodos , Dente/fisiologia
9.
J Digit Imaging ; 26(2): 163-72, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22584773

RESUMO

Three-dimensional (3-D) surface imaging has gained clinical acceptance, especially in the field of cranio-maxillo-facial and plastic, reconstructive, and aesthetic surgery. Six scanners based on different scanning principles (Minolta Vivid 910®, Polhemus FastSCAN™, GFM PRIMOS®, GFM TopoCAM®, Steinbichler Comet® Vario Zoom 250, 3dMD DSP 400®) were used to measure five sheep skulls of different sizes. In three areas with varying anatomical complexity (areas, 1 = high; 2 = moderate; 3 = low), 56 distances between 20 landmarks are defined on each skull. Manual measurement (MM), coordinate machine measurements (CMM) and computer tomography (CT) measurements were used to define a reference method for further precision and accuracy evaluation of different 3-D scanning systems. MM showed high correlation to CMM and CT measurements (both r = 0.987; p < 0.001) and served as the reference method. TopoCAM®, Comet® and Vivid 910® showed highest measurement precision over all areas of complexity; Vivid 910®, the Comet® and the DSP 400® demonstrated highest accuracy over all areas with Vivid 910® being most accurate in areas 1 and 3, and the DSP 400® most accurate in area 2. In accordance to the measured distance length, most 3-D devices present higher measurement precision and accuracy for large distances and lower degrees of precision and accuracy for short distances. In general, higher degrees of complexity are associated with lower 3-D assessment accuracy, suggesting that for optimal results, different types of scanners should be applied to specific clinical applications and medical problems according to their special construction designs and characteristics.


Assuntos
Face/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional/métodos , Crânio/diagnóstico por imagem , Animais , Pesquisa Biomédica , Modelos Lineares , Modelos Animais , Sensibilidade e Especificidade , Ovinos , Tomografia Computadorizada por Raios X/métodos
10.
Eur Radiol ; 22(2): 358-63, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21842433

RESUMO

OBJECTIVE: To demonstrate feasibility of near-real-time oculodynamic magnetic resonance imaging (od-MRI) in depicting extraocular muscles and correlate quantitatively the motion degree in comparison with clinical testing in patients with diplopia. METHODS: In 30 od-MRIs eye movements were tracked in the horizontal and sagittal plane using a a TrueFISP sequence with high temporal resolution. Three physicians graded the visibility of extraocular muscles by a qualitative scale. In 12 cases, the maximal monocular excursions in the horizontal and vertical direction of both eyes were measured in od-MRIs and a clinical test and correlated by the Pearson test. RESULTS: The medial and lateral rectus muscles were visible in the axial plane in 93% of the cases. The oblique, superior and inferior rectus muscles were overall only in 14% visible. Horizontal (p = 0,015) and vertical (p = 0,029) movements of the right eye and vertical movement of the left eye (p = 0,026) measured by od-MRI correlated positively to the clinical measurements. CONCLUSIONS: Od-MRI is a feasible technique. Visualization of the horizontal/vertical rectus muscles is better than for the superior/inferior oblique muscle. Od-MRI correlates well with clinical testing and may reproduce the extent of eye bulb motility and extraocular muscle structural or functional deteriorations. Key Points • Oculodynamic MRI technique helps clinicians to assess eye bulb motility disorders • MRI evaluation of eye movement provides functional information in cases of diplopia • Oculodynamic MRI reproduces excursion of extraocular muscles with good correlation with clinical testing • Dynamic MRI sequence supplements static orbital protocol for evaluation of motility disorders.


Assuntos
Diplopia/diagnóstico , Diplopia/patologia , Imageamento por Ressonância Magnética/métodos , Transtornos da Motilidade Ocular/patologia , Músculos Oculomotores/patologia , Órbita/patologia , Adulto , Movimentos Oculares , Estudos de Viabilidade , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Modelos Estatísticos , Movimento , Transtornos da Motilidade Ocular/diagnóstico , Reprodutibilidade dos Testes
11.
J Oral Maxillofac Surg ; 70(3): 677-84, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21807449

RESUMO

PURPOSE: Proteus syndrome is described as a progressive, asymmetric, disproportional overgrowth of various parts of the body. The theory of somatic mosaicism is widely accepted to be the cause of this disease. Affected patients present very heterogeneous symptoms, but in about 30% craniofacial deformities are the leading clinical features. Because no causal therapy exists, treatment options are limited to surgical improvement of functional constraints. MATERIALS AND METHODS: A computer-assisted method was used to increase the accuracy and safety of bone removal in the extracranial correction of cranial vault asymmetries. Descriptions of the diagnosis, preoperative planning, and intraoperative management of craniofacial dysmorphia caused by Proteus syndrome in a 6-year-old boy are presented. After computed tomography-based generation of a virtual 3-dimensional (3D) model of the patient and a haptic stereolithographic model to display the special pathology, flow-sensitized 4-dimensional magnetic resonance imaging was performed to clarify the properties of vascular formation inside the hyperostosis. To transfer the mathematically optimized preoperative planning of a new skull shape to the patient, a surgical guide was fabricated by rapid manufacturing. Intraoperative 3D real-time navigation was installed as an additional visualization and security feature. RESULTS: The surgery could be performed safely and quickly. Postoperative imaging showed that the surgical plan was realized with high accuracy. CONCLUSION: This newly developed and validated method can be successfully implemented in the operating room environment.


Assuntos
Anormalidades Craniofaciais/cirurgia , Imageamento Tridimensional , Procedimentos de Cirurgia Plástica/métodos , Síndrome de Proteu/cirurgia , Crânio/cirurgia , Cirurgia Assistida por Computador , Criança , Protocolos Clínicos , Simulação por Computador , Desenho Assistido por Computador , Anormalidades Craniofaciais/complicações , Anormalidades Craniofaciais/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Masculino , Modelos Anatômicos , Osteotomia/métodos , Planejamento de Assistência ao Paciente , Síndrome de Proteu/complicações , Síndrome de Proteu/diagnóstico por imagem , Radiografia , Reprodutibilidade dos Testes , Resultado do Tratamento
12.
J Craniofac Surg ; 23(2): e98-100, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22446472

RESUMO

The advent of resorbable osteosynthesis material has revolutionized craniomaxillofacial surgery. The need to provide rigid bony fixation in the surgical treatment of craniofacial deformities has inspired an ongoing evolution of surgical innovations and implants. Stability of the plates has been improved, but the duration of their stability remains an ongoing problem. In infant craniofacial fixation, it is important to provide initial stability, but after 4 to 6 weeks, this is no longer required as the brain is rapidly expanding. Surgery was performed on 10 patients with sagittal suture synostosis with conventional suture resection, remodeling, and fixation with resorbable miniplate (PolyMax-RAPID) struts held in position with modeled resorbable pockets affixed to the neurocranium with resorbable screws placed across the resected suture between June 2004 and September 2008. All the patients presented a satisfactory aesthetic result without complications after at least 1-year follow-up. We present a further innovative method of craniofacial fixation in infants using resorbable plates as floating struts providing stability and at the same time controlled dynamic expansion of the cranial vault guided by brain growth.


Assuntos
Implantes Absorvíveis , Craniossinostoses/cirurgia , Craniossinostoses/diagnóstico por imagem , Feminino , Humanos , Lactente , Masculino , Técnicas de Sutura , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
J Clin Med ; 10(3)2021 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-33498921

RESUMO

BACKGROUND: In order to overcome the geometrical and physical limitations of conventional rotating and piezosurgery instruments used to perform bone osteotomies, as well as the difficulties in translating digital planning to the operating room, a stand-alone robot-guided laser system has been developed by Advanced Osteotomy Tools, a Swiss start-up company. We present our experiences of the first-in-man use of the Cold Ablation Robot-guided Laser Osteotome (CARLO®). METHODS: The CARLO® device employs a stand-alone 2.94-µm erbium-doped yttrium aluminum garnet (Er:YAG) laser mounted on a robotic arm. A 19-year-old patient provided informed consent to undergo bimaxillary orthognathic surgery. A linear Le Fort I midface osteotomy was digitally planned and transferred to the CARLO® device. The linear part of the Le Fort I osteotomy was performed autonomously by the CARLO® device under direct visual control. All pre-, intra-, and postoperative technical difficulties and safety issues were documented. Accuracy was analyzed by superimposing pre- and postoperative computed tomography images. RESULTS: The CARLO® device performed the linear osteotomy without any technical or safety issues. There was a maximum difference of 0.8 mm between the planned and performed osteotomies, with a root-mean-square error of 1.0 mm. The patient showed normal postoperative healing with no complications. CONCLUSION: The newly developed stand-alone CARLO® device could be a useful alternative to conventional burs, drills, and piezosurgery instruments for performing osteotomies. However, the technical workflow concerning the positioning and fixation of the target marker and the implementation of active depth control still need to be improved. Further research to assess safety and accuracy is also necessary, especially at osteotomy sites where direct visual control is not possible. Finally, cost-effectiveness analysis comparing the use of the CARLO® device with gold-standard surgery protocols will help to define the role of the CARLO® device in the surgical landscape.

14.
J Clin Med ; 10(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34441859

RESUMO

Pure orbital blowout fractures occur within the confines of the internal orbital wall. Restoration of orbital form and volume is paramount to prevent functional and esthetic impairment. The anatomical peculiarity of the orbit has encouraged surgeons to develop implants with customized features to restore its architecture. This has resulted in worldwide clinical demand for patient-specific implants (PSIs) designed to fit precisely in the patient's unique anatomy. Material extrusion or Fused filament fabrication (FFF) three-dimensional (3D) printing technology has enabled the fabrication of implant-grade polymers such as Polyetheretherketone (PEEK), paving the way for a more sophisticated generation of biomaterials. This study evaluates the FFF 3D printed PEEK orbital mesh customized implants with a metric considering the relevant design, biomechanical, and morphological parameters. The performance of the implants is studied as a function of varying thicknesses and porous design constructs through a finite element (FE) based computational model and a decision matrix based statistical approach. The maximum stress values achieved in our results predict the high durability of the implants, and the maximum deformation values were under one-tenth of a millimeter (mm) domain in all the implant profile configurations. The circular patterned implant (0.9 mm) had the best performance score. The study demonstrates that compounding multi-design computational analysis with 3D printing can be beneficial for the optimal restoration of the orbital floor.

15.
Lasers Surg Med ; 42(8): 743-51, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20886507

RESUMO

OBJECTIVES: It was the aim of this study to compare the feasibility of complete osteotomy of long bones in sheep using a newly designed variable square pulsed Er:YAG laser and piezoelectric surgery. In addition to uneventful bone healing after laser osteotomy, the goal was to assess the possibility to cut thick bony structures with both techniques in a surgically acceptable time frame of 2-3 minutes. MATERIAL AND METHODS: A tibia midshaft osteotomy was performed in 24 sheep using either an Er:YAG laser (n = 12) or piezoelectric device (n = 12). Laser and piezoelectric groups were divided in two subgroups (n = 6) with sheep sacrificed after 2 and 3 months, respectively. A complete radiological, histological and histomorphometric analysis was performed to compare the course of bone/fracture healing and remodelling. RESULTS: Laser and piezoelectric osteotomies of the sheep tibia up to a depth of 22 mm were possible without any thermal damage. Radiological and histological results after 2 months showed primary gap healing with distinct periosteal callus formation on the transcortex. After 3 months, radiological and histological analysis revealed less callus formation on the transcortex, with almost no visible osteotomy gap and a distinct formation of lamellar bone crossing the original osteotomy gap. CONCLUSION: Er:YAG laser osteotomy can successfully be used in long bones with a depth of up to 22 mm, thus challenging the dogma of adverse effects of laser osteotomy due to thermal or other damages.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Osteotomia/instrumentação , Tíbia/cirurgia , Ultrassom , Animais , Estudos de Viabilidade , Feminino , Ovinos , Tíbia/patologia
16.
Lasers Med Sci ; 25(2): 239-49, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19680713

RESUMO

The aim of the study was to compare the histological results after complete osteotomies of the sheep tibia using either the prototype carbon dioxide (CO(2)) laser osteotome 'OsteoLAS' (n = 12) or an oscillating saw (n = 12). The laser parameters were as follows: wavelength 10.6 microm; energy of laser pulses 75-85 mJ; pulse duration 80 mus; pulse repetition rate 200 Hz; spot diameter 460 mum (1/e(2) level); radiant exposure 45-51 J/cm(2); peak irradiance 0.56-0.64 MW/cm(2). Both groups were divided into two subgroups (n = 6), and the animals were killed after 4 weeks or 12 weeks, respectively. Light and fluorescence microscopy with semiquantitative analysis and histomorphometry were performed to compare bone healing. Charring-free laser osteotomies were possible up to a depth of 20 mm with the short-pulsed CO(2) laser. The laser, however, required a significantly longer time to perform, and a wedge-shaped gap was present on the cis-cortex. After 4 weeks the osteotomy gaps were almost unchanged in both groups and filled with connective tissue. After 12 weeks the gaps were filled with newly formed bone in both groups. Primary gap healing was predominant in the laser group and longitudinal cortical remodelling in the control group. On a cellular level, no fundamental differences were observed for early and late stages of bone healing. Further research has to be focussed on improving the CO(2) laser ostetome in order to reduce the long duration of the laser osteotomy and the necessity of creating a wedge-shaped cut in thick bones.


Assuntos
Consolidação da Fratura , Lasers de Gás/uso terapêutico , Osteotomia/métodos , Animais , Modelos Animais , Ovinos , Tíbia/patologia , Tíbia/efeitos da radiação , Tíbia/cirurgia , Fraturas da Tíbia/patologia , Fatores de Tempo
17.
J Plast Reconstr Aesthet Surg ; 73(1): 98-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31711860

RESUMO

BACKGROUND: Precise, expensive individual saw guides are used with increasing frequency for the reconstruction of mandibular defects with fibular grafts. In this report, an alternative is presented - the Multiuse Cutting Jig (MUC-Jig, proprietary development). It is reusable, suitable for all patients, requires simple planning based on conventional CT imaging, and is more economical. METHODS: To investigate its precision, we conducted a nonblinded experimental study, with ten participating craniomaxillofacial surgeons. Osteotomies of four different fibula segments were carried out at the same angulation, with groups defined according to the proximal and distal fixed angulation: 45°, 30°, 15°, or 0°. The sagittal cut was performed proximally, with the coronal cut performed distally. The resulting 40 segments (n = 40) were analyzed with their Tx length (primary endpoint) and osteotomy angles, and compared to the original planning. RESULTS: The mean (SD) relative deviation of all grafts from the original planning was -0.08 mm (1.12) in length and -0.71° (3.15) for the angle. Only 45° (-2.04 ±â€¯3.71°) and 30° (-1.07 ±â€¯2.52°) cuts differed significantly (p < 0.05) from smaller angle grafts. The mean (SD) absolute deviation was 0.81 mm (0.27) in length and 2.13° (0.93) in graft angles. For individual transplants, 45° cuts (1.28 ±â€¯1.03 mm) differed significantly (p < 0.005) from others. We observed no differences in relative length or absolute angle deviation. CONCLUSIONS: The MUC-Jig is precise and cost-effective for osteotomies with medium angles and smooth reconstructions of template-guided procedures.


Assuntos
Fíbula/transplante , Retalhos de Tecido Biológico , Reconstrução Mandibular/instrumentação , Osteotomia/instrumentação , Transplante Ósseo/instrumentação , Angiografia por Tomografia Computadorizada , Desenho de Equipamento , Humanos , Invenções , Mandíbula/cirurgia , Modelos Anatômicos , Impressão Tridimensional , Instrumentos Cirúrgicos
18.
J Clin Med ; 9(11)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114485

RESUMO

Dental anomalies coincide with genetic disorders, and prenatal identification may contribute to a more accurate diagnosis. The aim of this study was to assess whether fetal Magnet Resonance Imaging (MRI) is suitable to visualize and investigate intrauterine dental development in the upper jaw, and to compare the quality of visibility of tooth buds between 1.5 Tesla (T) and 3T images. MR images of fetuses Gestational Week (GW) 26.71 ± 4.97 from 286 pregnant women with diagnoses unrelated to dental anomalies were assessed by three raters. We compared the visibility between groups and field strengths in five gestational age groups, using chi square and Fisher's exact tests. All ten primary tooth buds were identifiable in 5.4% at GW 18-21, in 75.5% at GW 26-29, and in 90.6% at GW 34+. Before GW 30, more tooth buds were identifiable on 3T images than on 1.5T images. Statistical significance was only reached for identification of incisors (p = 0.047). Therefore, 1.5T and 3T images are viable to visualize tooth buds, particularly after GW 25, and their analysis may serve as diagnostic criterion. MRI tooth bud data might have an impact on various fields of research, such as the maldevelopment of teeth and their causes. Analyzing tooth buds as an additional diagnostic criterion is not time consuming, and could lead to an improvement of syndrome diagnosis.

19.
J Clin Med ; 9(3)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192099

RESUMO

With the rapid progression of additive manufacturing and the emergence of new 3D printing technologies, accuracy assessment is mostly being performed on isosymmetric test bodies. However, the accuracy of anatomic models can vary. The dimensional accuracy of root mean square values in terms of trueness and precision of 50 mandible replicas, printed with five common printing technologies, were evaluated. The highest trueness was found for the selective laser sintering printer (0.11 ± 0.016 mm), followed by a binder jetting printer (0.14 ± 0.02 mm), and a fused filament fabrication printer (0.16 ± 0.009 mm). However, highest precision was identified for the fused filament fabrication printer (0.05 ± 0.005 mm) whereas other printers had marginally lower values. Despite the statistically significance (p < 0.001), these differences can be considered clinically insignificant. These findings demonstrate that all 3D printing technologies create models with satisfactory dimensional accuracy for surgical use. Since satisfactory results in terms of accuracy can be reached with most technologies, the choice should be more strongly based on the printing materials, the intended use, and the overall budget. The simplest printing technology (fused filament fabrication) always scored high and thus is a reliable choice for most purposes.

20.
Ther Innov Regul Sci ; 53(1): 110-119, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29714593

RESUMO

BACKGROUND: The aim was to analyze safety data associated with the maternal use of antiepileptic drugs in pregnancy and to assess the risk of cleft lip and/or palate (CL/P) as an outcome in the neonate. A parallel objective was to assess the completeness of the safety information concerning pregnancy exposures in the Summary of Product Characteristics (SmPCs) and the Patient Information (PI) in the USA and the UK. METHODS: We analyzed individual case safety reports of CL/P associated with antiepileptic drugs in the FDA Adverse Event Reporting System. For the antiepileptic drugs with signals (EB05 ≥ 2), we reviewed Drug Analysis Prints for CL/P cases in the UK Medicines and Healthcare products Regulatory Agency (MHRA). We performed descriptive analyses of relevant SmPCs and PIs in the UK and the USA using a checklist of recommendations collected from the literature. RESULTS: In total 817 CL/P reports were identified for 12 antiepileptic drugs in the FDA Adverse Event Reporting System. Ten of the 12 antiepileptic drugs were associated with 156 CL/P cases in the MHRA Sentinel. Safety information concerning pregnancy was found to be more comprehensive in UK SmPCs than in the US equivalents. CONCLUSIONS: There is statistical disproportionality in individual case safety reports indicative of an increased risk of CL/P with 12 antiepileptic drugs studied. More studies are required to explore the association between in utero exposure to antiepileptic drugs and the risk of CL/P. There are inconsistencies between the UK and US safety labels. CL/P associated with antiepileptic drugs is an important topic and requires providing inclusive, unbiased, up-to-date information to prescribers and women of childbearing age.


Assuntos
Anticonvulsivantes/efeitos adversos , Fenda Labial/induzido quimicamente , Fissura Palatina/induzido quimicamente , Sistemas de Notificação de Reações Adversas a Medicamentos , Feminino , Pessoal de Saúde , Humanos , Recém-Nascido , Troca Materno-Fetal , Pacientes , Gravidez , Vigilância de Produtos Comercializados , Risco , Estados Unidos , United States Food and Drug Administration
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