Analyzing results of cervical sagittal parameters in patients operated with polyetheretherketone cages without plate.

Study Design: This was a retrospective longitudinal observational study. Purpose: The purpose of this study was to analyze the results of cervical sagittal parameters on preoperative and postoperative lateral radiographs in anterior cervical discectomy and fusion (ACDF). ACDF is believed to change craniocervical parameters and thus cervical curvature using polyetheretherketone (PEEK) or titanium cages with or without self-locking as well as an anterior plate, the latter of which has not been shown to provide better clinical or radiological results. Overview of Literature: Cervical spondylotic myelopathy (CSM) is a common degenerative pathology that can affect one or more levels and treatment has varied over time trying to maintain sagittal parameters within acceptable values where the ACDF is the main treatment. Materials and Methods: The study was performed in patients with CSM who underwent anterior cervical discectomy, and their pre- and postoperative radiographs were analyzed using Surgimap software a few days before and 3 months after surgery. Results: Fifteen files were included in the study. Statistically significant sagittal balance variables were observed in cervical lordosis (CL) with an increase of 4.73° (P = 0.019) and T1 slope (T1S)-CL with a decrease of -5.93° (P = 0.007). Conclusions: CL and T1S-CL showed favorably modified values when performing ACDF using stand-alone PEEK cages without the need for self-blocking or an anterior plate.

Finite Element Analysis of Patient-Specific 3D-Printed Cranial Implant Manufactured with PMMA and PEEK: A Mechanical Comparative Study.

This article reports on a patient who required a cranial protection system. Using additive manufacturing techniques and surgical planning with the help of bio-models, a patient-specific bone implant solution was proposed that allows aesthetic restoration of the affected area and provides an adequate level of protection. In addition, through a comparative analysis with finite elements, the mechanical response to external actions of the medical device, printed with two materials: polymethylmethacrylate (PMMA) and polyether-ether-ketone (PEEK), is simulated. The tested materials have recognized biocompatibility properties, but their costs on the market differ significantly. The results obtained demonstrate the similarities in the responses of both materials. It offers the possibility that low-income people can access these devices, guaranteeing adequate biomechanical safety, considering that PMMA is a much cheaper material than PEEK.

The effect of different framework's material on strain induced in distal abutment in mandibular Kennedy's class II: an in-vitro study / O efeito de diferentes materiais de estrutura na deformação induzida na distal do pilar da classe II de Kennedy mandibular: um estudo in vitro

Objective: This study aims to compare the strain induced in the supporting structures of unilateral mandibular removable partial denture frameworks retained by extra-coronal attachments fabricated with three different materials. Material and Methods: Three mandibular class II digitally designed and printed acrylic models with detachable abutments were used to fabricate three removable partial denture framework with extra coronal attachments from three different materials. A total of 33 models were prepared for strain testing (n=11). Models were divided into three groups according to framework's material: porcelain fused to cobalt chromium (PFM), polyetherketoneketone (PEKK) and polyetheretherketone (PEEK) group. Unilateral load of 60 N was applied in the three groups and strains were measured around the main abutment and saddle area using strain gauge. Results: Statistical analysis was performed using Shapiro-Wilk's test and by checking data distribution. Data were found to be non-parametric and were analysed using Kruskal-Wallis test followed by Dunn's post hoc test with Bonferroni correction. PFM group showed significantly the highest strain values around abutment, slot 1 (1mm distal to the socket of the last abutment) and slot 2 (1 cm away from slot 1) respectively (843.00±23.08, 91.00±6.52 and 1274.00±65.71) than the other tested groups (p<0.05) at same tested sites respectively followed by PEKK group (384.00±37.48, 81.00±2.24 and 135.00±0.00) and PEEK group (29.00±4.18, 63.00±4.47 and 52.00±5.70). Conclusions: PEEK and PEKK for partial denture framework with extra coronal attachments are adequate alternative to PFM due to their good mechanical response applying less strain on supportive structures in free-end cases. PEEK induces lower strain magnitude on the supporting structures when compared to PEKK. (AU)

Objetivo: Este estudo tem como objetivo comparar a tensão induzida nas estruturas de suporte de estruturas de próteses parciais removíveis mandibulares unilateraisretidas por encaixes extracoronários fabricados com três materiais diferentes. Material e Métodos: Três modelos mandibulares de classe II digitalmente projetados e impressos em acrílico com pilares destacáveis foram usados para fabricar três estruturas de próteses parciais removíveis com encaixes extracoronários de três materiais diferentes. Um total de 33 modelos foram preparados para testes de deformação (n=11). Os modelos foram divididos em três grupos de acordo com o material da estrutura: porcelana fundida com cobalto-cromo (PFM), poliétercetonacetona (PEKK) e polieteretercetona (PEEK). Carga unilateral de 60 N foi aplicada nos três grupos e as deformações foram medidas em torno do pilar principal e área de sela usando medido de tensão. Resultados: A análise estatística foi realizada por meio do teste de Shapiro-Wilk e com a verificação da distribuição dos dados. Os dados mostraram-se não paramétricos e foram analisados pelo teste de Kruskal-Wallis seguido pelo de Dunn com correção de Bonferroni. O grupo PFM mostrou significativamente os maiores valores de tensão ao redor do pilar, slot 1 (1mm distal do último pilar) e slot 2 (1 cm de distância do slot 1) respectivamente (843,00±23,08, 91,00±6,52 e 1274,00±65,71) do que os outros grupos testados (p<0,05) nos mesmos locais testados, respectivamente, seguido pelo grupo PEKK (384,00±37,48, 81,00±2,24 e 135,00±0,00) e grupo PEEK (29,00±4,18, 63,00±4,47 e 52,00±5,70). Conclusão: PEEK e PEKK para estrutura de prótese parcial com encaixes extracoronários são alternativas adequadas ao PFM devido à sua boa resposta mecânica aplicando menos tensão nas estruturas de suporte em casos de extremidade livre. O PEEK induz menor magnitude de deformação nas estruturas de suporte quando comparado ao PEKK (AU)

Application of polyetheretherketone (PEEK) posts: evaluation of fracture resistance and stress distribution in the root: in vitro and finite element analyses

Abstract To evaluate the feasibility of using a milled polyetheretherketone (PEEK) post and core in endodontically treated teeth with or without a ferrule. Sixty bovine tooth roots were endodontically treated followed by cementation of intraradicular retainers (IR), according to each experimental group: a) non-ferrule glass fiber post (f0FP); b) 2-mm-ferrule glass fiber post (f2FP); c) non-ferrule resized glass fiber post (f0PR); d) 2-mm-ferrule resized glass fiber post (f2PR); e) non-ferrule PEEK post and core (f0PPC); and f) 2-mm-ferrule PEEK post and core (f2PPC). Metal crowns were made and cemented. A periodontal ligament was simulated using polyether. A force was applied to the palatine portion of each sample at 45°, until fracture. Fracture resistance data were submitted to two-way ANOVA and Tukey's test (α = 0.05). Three-dimensional digital models were developed to calculate the tensions formed in the root using finite element analysis. Models of glass fiber posts and PEEK posts and cores were evaluated with or without a ferrule. The results were analyzed by the Mohr-Coulomb criterion. The type of IR was not influenced by fracture strength (p = 0.243). There were significant statistical differences among the remaining factors. Ferrule groups had greater fracture resistance, and the failure mode of teeth with a ferrule was more catastrophic than the non-ferrule group. A ferrule increases fracture resistance and influences failure mode; the PEEK post and core did not modify the biomechanics of endodontically treated teeth, and resembled the glass fiber post results. The crack initiation point differed between the ferrule and non-ferrule groups.

Comparison of shear bond strength and color reproduction of two different high-performance polymers veneered with two different thicknesses of resin composite: an in-vitro study / Comparação da resistência ao cisalhamento e reprodução de cor de dois diferentes polímeros de alto desempenho revestidos com duas diferentes espessuras de resina composta: um estudo in vitro

Objective: to evaluate the effect of material type and veneer thickness on the final color and shear bond strength of PEEK bilayered restorations. Material and Methods: sixty-four square-shaped core specimens (7×7×2), were fabricated by CAD/CAM technology from two high-strength polymers, BioHPP (High-Performance Polymer, group B n=32), and Pekkton® ivory (PolyEtherKetoneKetone, group P n=32) then were veneered with resin composite (crea.lign dentin A3). Specimens from each group were divided (n=16) according to the veneer layer thickness (0.5 & 1 mm), then according to the test applied (n=8), either ΔE or shear bond strength (SBS). Specimen surfaces were treated according to the manufacturer's instructions. Specimens were veneered according to the manufacturer's instructions.The mode of failure was evaluated under a stereomicroscope at 40 x magnification after the shear bond strength test. Results: data showed parametric distribution and variance homogeneity and were analyzed using two-way ANOVA. The significance level was set at p<0.05 for all tests. Statistical analysis was performed with the R statistical analysis software version 4.3.1.Results of two-way ANOVA showed that material types and veneer thicknesses had an individual significant effect on the color change. For the shear bond strength, only the sample thickness (1mm) had a significant effect (p=0.033). The majority of samples in different groups presented a mixed failure mode with all the differences being not statistically significant (p>0.05). Conclusion: the thickness of the resin composite veneer can significantly affect the final esthetic outcome and shear bond strength of a bilayered restoration.(AU)

Objetivo: avaliar o efeito do tipo de material e da espessura do revestimento na cor final e na resistência ao cisalhamento de restaurações em duas camadas de PEEK. Material e Métodos: foram fabricados 64 espécimes com núcleo de formato quadrado (7x7x2) usando tecnologia CAD/CAM a partir de dois polímeros de alta resistência, BioHPP (Polímero de Alto Desempenho, grupo B n=32) e Pekkton ivory (Polieterecetona cetona, grupo P n=32), que foram então revestidos com resina composta (crea.lign dentin A3). Os espécimes de cada grupo foram divididos (n=16) de acordo com a espessura do revestimento (0,5 e 1 mm), e depois de acordo com o teste aplicado (n=8), seja ΔE ou resistência ao cisalhamento (SBS). As superfícies dos espécimes foram tratadas de acordo com as instruções do fabricante. Os espécimes foram revestidos de acordo com as instruções do fabricante. O modo de falha foi avaliado sob um estereomicroscópio com ampliação de 40x após o teste de resistência ao cisalhamento. Resultados: os dados apresentaram distribuição paramétrica e homogeneidade de variância e foram analisados por ANOVA de duas vias. O nível de significância foi estabelecido em p<0,05 para todos os testes. A análise estatística foi realizada com o software de análise estatística R, versão 4.3.1. Os resultados da ANOVA de duas vias mostraram que os tipos de materiais e as espessuras do revestimento tiveram um efeito significativo individual na mudança de cor. Para a resistência ao cisalhamento, apenas a espessura da amostra (1mm) teve um efeito significativo (p=0,033). A maioria das amostras em diferentes grupos apresentou um modo de falha misto, com todas as diferenças não sendo estatisticamente significativas (p>0,05). Conclusão:a espessura do revestimento de resina composta pode afetar significativamente o resultado estético final e a resistência ao cisalhamento de uma restauração em duas camadas.(AU)

Strategies to Reduce Biofilm Formation in PEEK Materials Applied to Implant Dentistry-A Comprehensive Review.

Polyether-ether-ketone (PEEK) has emerged in Implant Dentistry with a series of short-time applications and as a promising material to substitute definitive dental implants. Several strategies have been investigated to diminish biofilm formation on the PEEK surface aiming to decrease the possibility of related infections. Therefore, a comprehensive review was carried out in order to compare PEEK with materials widely used nowadays in Implant Dentistry, such as titanium and zirconia, placing emphasis on studies investigating its ability to grant or prevent biofilm formation. Most studies failed to reveal significant antimicrobial activity in pure PEEK, while several studies described new strategies to reduce biofilm formation and bacterial colonization on this material. Those include the PEEK sulfonation process, incorporation of therapeutic and bioactive agents in PEEK matrix or on PEEK surface, PEEK coatings and incorporation of reinforcement agents, in order to produce nanocomposites or blends. The two most analyzed surface properties were contact angle and roughness, while the most studied bacteria were Escherichia coli and Staphylococcus aureus. Despite PEEK's susceptibility to biofilm formation, a great number of strategies discussed in this study were able to improve its antibiofilm and antimicrobial properties.

Thermal Localization Improves the Interlayer Adhesion and Structural Integrity of 3D printed PEEK Lumbar Spinal Cages.

Additive manufacturing (AM) is a potential application for polyetheretherketone (PEEK) spinal interbody fusion cages, which were introduced as an alternative to titanium cages because of their biocompatibility, radiolucency and strength. However, AM of PEEK is challenging due to high melting temperature and thermal gradient. Although fused filament fabrication (FFF) techniques have been shown to 3D print PEEK, layer delamination was identified in PEEK cages printed with a first generation FFF PEEK printer [1]. A standard cage design [2] was 3D printed with a second generation FFF PEEK printer. The effect of changing layer cooling time on FFF cages' mechanical strength was investigated by varying nozzle sizes (0.2 mm and 0.4 mm), print speeds (1500 and 2500 mm/min), and the number of cages printed in a single build (1, 4 and 8). To calculate the porosity percentage, FFF cages were micro-CT scanned prior to destructive testing. Mechanical tests were then conducted on FFF cages according to ASTM F2077 [2]. Although altering the cooling time of a layer was not able to change the failure mechanism of FFF cages, it was able to improve cages' mechanical strength. Printing a single cage per build caused a higher ultimate load than printing multiple cages per build. Regardless of the cage number printed per build, cages printed with bigger nozzle diameter achieved higher ultimate load compared to cages printed with smaller nozzle diameter. Printing with a bigger nozzle diameter resulted in less porosity, which might have an additional affect on the interlayer delamination failure mechanism.

Flexural strength of polyether ether ketone high-performance polyether in comparison with base metal alloy and zirconia ceramic / Resistencia a la flexión del poliéter éter cetona poliéter de alto rendimiento en comparación con la aleación de metal base y la cerámica de circonio

Optimal flexural strength is a critical prerequisite for prosthetic frameworks. This study aimed to assess the flexural strength of polyether ether ketone (PEEK) polymer compared to a base metal alloy and high-strength Zirconia ceramic commonly used in prosthodontic treatments. Materials and Methods: In this in vitro, experimental study, 10 bar-shaped samples measuring 18×5×2mm were fabricated of each the PEEK polymer, nickel-chromium base metal alloy and zirconia ceramic. Half of the samples in each group were subjected to 5000 thermal cycles between 5°C - 55°C with 20 seconds of dwell time and 20 seconds of transfer time to simulate oral conditions. All samples then underwent three-point bending test. Two-way ANOVA followed by Tukey's test were applied to compare the mean flexural strength of the groups with and without thermocycling at 0.05 level of significance. Results: The flexural strength of base metal alloy, Zirconia and PEEK was 1387.70±45.50 MPa, 895.13±13.99 MPa and 192.10±5.37 MPa, respectively. The difference was significant among the groups (p<0.001). Thermocycling had no significant effect on the flexural strength of samples in any group (p=0.306). Conclusion: PEEK high-performance polymer had a lower flexural strength than base metal alloy and Zirconia ceramic, and its flexural strength was not affected by thermocycling. PEEK seems to be able to resist masticatory forces in the oral cavity pending further in vitro and clinical studies.

La resistencia a la flexión óptima es un requisito previo crítico para los marcos protésicos. Este estudio tuvo como objetivo evaluar la resistencia a la flexión del polímero de poliéter éter cetona (PEEK) en comparación con una aleación de metal base y cerámica de Zirconia de alta resistencia comúnmente utilizada en tratamientos de prostodoncia. Materiales and Métodos: En este estudio experimentalin vitro, se fabricaron 10 muestras en forma de barra de 18 × 5 × 2mm de cada polímero PEEK, aleación de metal base de níquel-cromo y cerámica de circonio. La mitad de las muestras en cada grupo fueron sometidas a 5000 ciclos térmicos entre 5°C - 55°C con 20 segundos de tiempo de permanencia y 20 segundos de tiempo de transferencia para simular condiciones orales. Todas las muestras se sometieron a una prueba de flexión de tres puntos. Se aplicó ANOVA bidireccional seguido de la prueba de Tukey para comparar la resistencia a la flexión media de los grupos con y sin termociclado a un nivel de significancia de 0.05. Resultados: La resistencia a la flexión de la aleación de metal base, Zirconia y PEEK fue de 1387,70 ± 45,50 MPa; 895,13 ± 13,99 MPa y 192.10 ± 5,37 MPa, respectivamente. La diferencia fue significativa entre los grupos (p<0,001). El termociclado no tuvo un efecto significativo sobre la resistencia a la flexión de las muestras en ningún grupo (p=0,306).Conclusión:El polímero de alto rendimiento PEEK tiene una resistencia a la flexión más baja que la aleación de metal base y la cerámica de circonio, y su resistencia a la flexión no se vio afectada por el termociclado. PEEK parece ser capaz de resistir las fuerzas masticatorias en la cavidad oral, con la necesidad de más estudios in vitroy clínicos.

[Reconstrucción ósea de defectos craneales secundarios a traumatismo con implantes personalizados]. / Cranial bone reconstruction with customized implants after trauma.

INTRODUCCIÓN: Los defectos craneales secundarios a traumatismos son frecuentes. Por lo común se reparan de forma secundaria por sintomatología como el síndrome del paciente trepanado, por protección cerebral y por el aspecto cosmético. Históricamente se han utilizado diversos materiales para la reconstrucción. CASOS CLÍNICOS: Se presentan cinco casos de pacientes reconstruidos con implantes personalizados de polieteretercetona (PEEK) o polimetilmetacrilato poroso (PMMA). Las localizaciones afectaron el frontal, el borde orbitario superior y el techo orbitario en cuatro casos, y la porción lateral del frontal, la zona temporoparietal y el borde del occipital en un caso. La reconstrucción en cuatro pacientes fue entre 6 y 12 meses después de la lesión, y en un caso después de 25 años. En dos casos se requirió expansión tisular antes de colocar el implante. RESULTADOS: Cuatro pacientes evolucionaron favorablemente, con mejoría de los síntomas neurológicos, forma y contorno adecuados, así como un proceso de cicatrización adecuada de los colgajos de piel cabelluda. Un paciente presentó infección por Staphylococcus aureus, atribuida a la presencia de un mucocele y una fístula de la vía aérea a la cavidad craneal, lo que hizo necesario retirar el implante. CONCLUSIONES: Los implantes personalizados son un recurso útil para defectos óseos craneales. Brindan resultados satisfactorios desde el punto de vista funcional y cosmético. Deben tomarse precauciones respecto al tratamiento de las lesiones que afecten el seno frontal, para evitar la comunicación entre la vía aérea y la cavidad craneal. INTRODUCTION: Cranial defects due to trauma are frequent. They are usually repaired in a secondary fashion due to features such as syndrome of the trephined, for brain protection and for cosmetic purposes. Historically, various materials have been used for reconstruction. CASE REPORTS: Five cases of patients reconstructed with customized polyetheretherketone (PEEK) o polymethyl methacrylate (PMMA) implants are presented. Defects involved the frontal bone, superior orbital rim and orbital roof in four cases, and the lateral area of the frontal bone, the temporoparietal area and the border of the occipital bone in one. In four patients, reconstruction took place between 6 and 12 months after the injury; in one patient, after 25 years. Two cases required tissue expansion before placing the implant. RESULTS: Four patients evolved favorably, with improvement in neurologic symptoms and adequate shape and contour, plus adequate healing of the scalp flaps. One patient had an infection due to Staphylococcus aureus, attributed to a mucocele and fistula between the airway and the cranial cavity, leading to removal of the implant. CONCLUSIONS: Customized implants are a useful resource for cranial defects. They offer satisfactory results, both functional and cosmetic. Precautions should be taken in treating injuries that involve the frontal sinus, to ensure there is no communication between the airway and the cranial cavity.

Titanium versus polyetheretherketone implants for vertebral body replacement in the treatment of 77 thoracolumbar spinal fractures.

BACKGROUND: Titanium and polyetheretherketone (PEEK) implants have been used in spinal surgery with low rejection rates. Compared to titanium, PEEK has many advantages, including a density more similar to that of bone, radiolucency, and a lack of artifacts in computed tomography (CT) and magnetic resonance imaging (MRI). In this study, we evaluated the effectiveness of PEEK cages as an alternative to titanium for bone fusion after fractures of the thoracolumbar spine. We also propose a classification to the impaction index. METHODS: We evaluated 77 patients with fractures of the thoracic or lumbar spine who were treated by anterior fixation with titanium cages (TeCorp®) in 46 (59.7%) patients or PEEK (Verte-stak®) in 31 (40.3%) patients from 2006 to 2012 (Neurological Hospital of Lyon). RESULTS: The titanium group achieved 100% fusion, and the PEEK group achieved 96.3% fusion. The titanium systems correlated with higher impact stress directed toward the lower and upper plateaus of the fused vertebrae; there were no nonunions for those treated with titanium group. Nevertheless, there was only one in the PEEK group. There was no significant difference in the pain scale outcomes for patients with ±10 degrees of the sagittal angle. Statistically, it is not possible to associate the variation of sagittal alignment or the impaction with symptoms of pain. The complication rate related to the implantation of cages was low. CONCLUSIONS: Titanium and PEEK are thus equally effective options for the reconstruction of the anterior column. PEEK is advantageous because its radiolucency facilitates the visualization of bone bridges.

Marginal healing using Polyetheretherketone as healing abutments: an experimental study in dogs.

OBJECTIVE: To evaluate the marginal soft and hard tissue healing at titanium and Polyetheretherketone (PEEK) healing implant abutments over a 4-month period. MATERIAL AND METHODS: In six Labrador dogs, all mandibular premolars and first molars were extracted. After 4 months of healing, flaps were elevated, and two implants were installed at each side of the mandible, one in the premolar and the other in the molar regions. Four different types of healing abutments were positioned on the top of each implant: (i) titanium (Ti); (ii) PEEK material bonded to a base made of titanium (Ti-P), randomly positioned in the premolar region; (iii) PEEK, pristine (P); and (iv) PEEK, roughened (P-R), randomly positioned in the molar region. The flaps were sutured to allow a non-submerged healing, and after 4 months, the animals were sacrificed and ground sections obtained for histological evaluation. RESULTS: A higher resorption of the buccal bone crest was observed at the PEEK bonded to a base made of titanium abutments (1.0 ± 0.3 mm) compared to those made of titanium (0.3 ± 0.4 mm). However, similar dimensions of the peri-implant mucosa and similar locations of the soft tissues in relation to the implant shoulder were observed. No statistically significant differences were seen in the outcomes when the pristine PEEK was compared with the roughened PEEK abutments. The mean apical extension of the junctional epithelium did not exceed the implant shoulder at any of the abutment types used. CONCLUSIONS: The coronal level of the hard and soft tissues allows the conclusion that the use of PEEK as healing abutments may be indicated.

Bonding of the Polymer Polyetheretherketone (PEEK) to Human Dentin: Effect of Surface Treatments

Abstract Polyetheretherketone (PEEK) is a material suitable for frameworks of fixed dental prostheses. The effect of different surface treatments on the bond strength of PEEK bonded to human dentin was evaluated. One hundred PEEK cylinders (3 mm×3 mm) were divided into five groups according to surface treatment: silica coating, sandblasting with 45 μm Al2O3 particles, etching with 98% sulfuric acid for 5, 30 and for 60 s. These cylinders were luted with resin cement onto 50 human molars. First, each tooth was embedded in epoxy resin and the buccal dentin surface was exposed. Then, two delimited dentin areas (Æ:3 mm) per tooth were etched with 35% phosphoric acid and bonded with a two-step self-priming adhesive system. After the luting procedure the specimens were stored in water (24 h/37 °C). Shear bond strength (SBS) was tested using a universal testing machine (crosshead speed 0.5 mm/min; load cell 50 kgf) and failure types were assessed. Stress data (MPa) were analyzed using the Kruskal-Wallis test. Comparison of the proportions of different failure types was performed using the Bonferroni method (p<0.05). Kruskal-Wallis demonstrated that differences among groups were not significant (p=0.187). Mean SBS were as follows: silica coating, 2.12±1.12 MPa; sandblasting, 2.37±0.86 MPa; sulfuric acid 5 s, 2.28±1.75 MPa; sulfuric acid 30 s, 1.80±0.85 MPa; sulfuric acid 60 s, 1.67±0.94 MPa. Adhesive and mixed failures were predominant in all groups. Both physical and chemical surface treatments produced adhesion between PEEK, resin cement and dentin.

Resumo O poli-éter-éter-cetona (PEEK) é um material indicado para as estruturas de próteses parciais fixas. O efeito de diferentes tratamentos de superfície na resistência de união entre PEEK e dentina humana foi avaliado. Cem cilindros de PEEK (3 mm×3 mm) foram divididos em cinco grupos de acordo com tratamento de superfície: silicatização, jateamento com partículas de Al2O3 45 µm, condicionamento com ácido sulfúrico 98% por 5, 30 e 60 s. Esses cilindros foram cimentados com cimento resinoso em cinquenta molares humanos. Primeiro, cada dente foi incluído em resina epóxica e a superfície dentinária vestibular foi exposta. Depois, duas áreas (Æ:3 mm) em dentina/por dente foram delimitadas, condicionadas com ácido fosfórico a 35% e receberam aplicação de um sistema adesivo de dois passos. Após o procedimento de cimentação, as amostras foram armazenadas em água (24 h/37 °C). A resistência da união ao cisalhamento (SBS) foi testada em uma máquina universal de ensaios (velocidade 0,5 mm/min; célula de carga 50 kgf), e foram avaliados os tipos de falha. Os dados de tensão (MPa) foram analisados pelo teste de Kruskal-Wallis. A comparação das percentagens de diferentes tipos de falha foi realizada utilizando o método de Bonferroni (p<0,05). O teste de Kruskal-Wallis demonstrou que as diferenças entre os grupos não foram significantes (p=0,187). As médias de SBS foram: silicatização, 2,12±1,12 MPa; jateamento, 2,37±0,86 MPa; ácido sulfúrico por 5 s, de 2,28±1,75 MPa; ácido sulfúrico por 30 s, 1,80±0,85 MPa, ácido sulfúrico por 60 s, 1,67±0,94 MPa. Falhas adesivas e mistas foram predominantes em todos os grupos. Ambos tratamentos de superfície, físicos e químicos, promoveram adesão entre PEEK, cimento resinoso e dentina.

Reconstrucción mandibular con implante hecho a medida de polieteretercetona / Mandibular reconstruction with polyetheretherketone computer designed implant

Se describe el caso de un varón de 21 años, que ingresa a emergencia por sufrir un traumatismo, por arma de fuego de alta velocidad. El área comprometida es el tercio inferior facial, con extensión a las regiones submentoniana y submandibulares. El paciente presentó una fractura conminuta en la mitad inferior mandibular y dos fracturas con desplazamiento en la mitad superior mandibular, sin pérdida ni compromiso de piezas dentarias. Posterior a la reducción cruenta y osteosíntesis con alambre quirúrgico realizada en emergencia, en la reconstrucción se utilizó un implante hecho a medida basado en imágenes tomográficas. El implante de polieteretercetona (PEEK) fue seleccionado para reemplazar la pérdida ósea y para restaurar la anatomía facial. Los implantes de PEEK son actualmente una nueva opción biocompatible, simple y versátil para reconstrucciones mandibulares complejas Se presentan las imágenes tomográficas antes y después del implante, imágenes del paciente antes y después del implante y el proceso quirúrgico de implante.

A 22 years old male was referred to emergency for a gunshot trauma that involves the inferior third of the face with extension to the both submandibular and submental regions. The patient presented at the inferior half of the mandible, bodies and symphysis, a comminuted mandible fracture and two displaced fractures at the upper half of the mandible; though no teeth were missing. He underwent at emergency an open reduction and osteosynthesis with wires. A polyetheretherketone (PEEK) computer designed implant was placed to replace the lost bone tissue and restore the facial aesthetics. The PEEK implant is actually a new, simple and versatile method for complex mandibular reconstructions.

Reconstrucción mandibular con implante hecho a medida de polieteretercetona / Mandibular reconstruction with polyetheretherketone computer designed implant

Se describe el caso de un varón de 21 años, que ingresa a emergencia por sufrir un traumatismo, por arma de fuego de alta velocidad. El área comprometida es el tercio inferior facial, con extensión a las regiones submentoniana y submandibulares. El paciente presentó una fractura conminuta en la mitad inferior mandibular y dos fracturas con desplazamiento en la mitad superior mandibular, sin pérdida ni compromiso de piezas dentarias. Posterior a la reducción cruenta y osteosíntesis con alambre quirúrgico realizada en emergencia, en la reconstrucción se utilizó un implante hecho a medida basado en imágenes tomográficas. El implante de polieteretercetona (PEEK) fue seleccionado para reemplazar la pérdida ósea y para restaurar la anatomía facial. Los implantes de PEEK son actualmente una nueva opción biocompatible, simple y versátil para reconstrucciones mandibulares complejas Se presentan las imágenes tomográficas antes y después del implante, imágenes del paciente antes y después del implante y el proceso quirúrgico de implante.

A 22 years old male was referred to emergency for a gunshot trauma that involves the inferior third of the face with extension to the both submandibular and submental regions. The patient presented at the inferior half of the mandible, bodies and symphysis, a comminuted mandible fracture and two displaced fractures at the upper half of the mandible; though no teeth were missing. He underwent at emergency an open reduction and osteosynthesis with wires. A polyetheretherketone (PEEK) computer designed implant was placed to replace the lost bone tissue and restore the facial aesthetics. The PEEK implant is actually a new, simple and versatile method for complex mandibular reconstructions.

[Use of the PEEK cage in cervical spondylosis treatment]. / Uso de caja de PEEK (Poli-ether-ether-ketona) parael tratamiento de la espondilosis cervical.

BACKGROUND: Decompression and fusion with autograft is the gold standard technique in the treatment of cervical canal strait. Using PEEK cages or boxes of non-absorbable polymer with elasticity similar to bone, radiolucent, reduces morbidity and same degree of fusion. METHODS: A case series, prospective, longitudinal, deliberate intervention, evaluation panel before and after 2 years follow-up. Discectomy and PEEK housing placement with autologous graft. Arthrodesis were evaluated, cervical lordosis, intervertebral space height, pain evaluated with Visual Analogue Scale, Neck Disability Index, operative time, intraoperative bleeding, hospital stay and complications. Statistical analysis with t Sudent, Wilcoxon and Fisher's exact text. RESULTS: Of 17 patients studied, 9 (53%) were female. Average age 62 years. The most affected level was C5-6, C6-7 with 5 patients. Melting was found at 100%. There was no sag or migration of the box, space height was conserved, but segmental lordosis was not retained. Clinical improvement in all patients as well as disability index was seen. Bleeding was on average 187 mL. CONCLUSION: With regard to symptom improvement, conservation of interspace height and back, no segmental lordosis conservation and fusion using PEEK box is consistent with the literature. We suggest using anterior plate to maintain cervical lordosis. We found a melt index of 100%. We found clinical improvement of symptoms, pain and disability, and a global loss of cervical lordosis.

Antecedentes: la descompresión y artrodesis con auto-injerto es el patrón de referencia para el tratamiento del conducto cervical estrecho. El uso de cajas de PEEK polímero no reabsorbible, con elasticidad similar al hueso, radiolúcido, y mismo grado de fusión reduce la morbilidad. aterial y métodos: estudio de serie de casos, prospectivo, longitudinal, de intervención deliberada, evaluación en grupol antes y después, seguimiento a dos años. Discoidectomía y colocación de caja de PEEK con injerto autólogo. Se evaluaron artrodesis, lordosis cervical, altura del espacio intervertebral, dolor mediante escala visual análoga, índice de discapacidad cervical, tiempo quirúrgico, sangrado transoperatorio, estancia intrahospitalaria y complicaciones. Análisis estadístico con t de Student, Wilcoxon y exacta de Fisher. Resultados: de 17 pacientes estudiados, 9 (53%) eran del sexo femenino. La edad promedio 62 años. Sangrado promedio de 187 mL. El nivel más afectado fue C5-C6, C6-C7 en cinco pacientes. Se encontró fusión al 100% sin hundimiento ni migración de la caja, altura del espacio conservada, pero no se conservó la lordosis segmentaria. Mejoría clínica en todos los pacientes, y del índice de discapacidad. Conclusión: la disminución de los síntomas, la conservación de la altura del espacio anterior y posterior, la no conservación de la lordosis segmentaria y la fusión con caja de PEEK fueron congruentes con lo reportado en la bibliografía. Se sugiere utilizar la placa anterior para mantener la lordosis cervical. El índice de fusión encontrado fue de 100%, con disminución de los síntomas de dolor y discapacidad. Pérdida de lordosis cervical global.

Reconstrucción de la bóveda craneana con implante de poli-éter-éter-cetona diseñado por computadora: informe de un caso / Cranial vault reconstruction using computer-designed polyetheretherketone (PEEK) implant: case report

Introducción: La reconstrucción de los huesos del cráneo es un procedimiento complejo y representa un reto para el grupo médico tratante; generalmente se realiza en pacientes con pérdida de la bóveda craneana secundaria a procesos infecciosos crónicos no controlados o por osteorradionecrosis, lo que implica mayor posibilidad de fracaso o rechazo de los materiales utilizados para la reparación del defecto. La selección del material para sustituir la bóveda craneana es difícil debido a la diversidad de productos existentes; el material debe ser inerte, ligero, fácil de colocar y adaptable al defecto, con lo cual se ofrece mejores resultados estéticos y funcionales. Con el diseño por computadora del implante es posible ofrecer un implante individual y específico para cada defecto y paciente. Caso clínico: Mujer con diagnóstico de estesioneuroblastoma tratada con resección craneofacial anterior y radioterapia; como complicación presentó osteomielitis y osteorradionecrosis y, consecuentemente, pérdida de la bóveda craneana en la región frontal; este defecto fue reconstruido con un implante de poli-éter-éter-cetona diseñado por computadora con base en el defecto evaluado por tomografía computarizada. Se muestran los resultados obtenidos. Conclusiones: El implante diseñado por computadora realizado con poli-éter-éter-cetona es una alternativa segura, fácil de usar y con gran adaptabilidad a los defectos de la bóveda craneana.

BACKGROUND: Reconstruction of the bones of the skull is a complex procedure and represents a challenge for the surgical team. It is generally performed in patients who have loss of the cranial vault secondary to chronic infection or uncontrolled osteoradionecrosis, indicating a greater chance of failure or rejection of the materials used for repair of the defect. Selection of material to replace the cranial vault is complex due to the diversity of existing products. The ideal material is inert, lightweight, easy to fit and adaptable to the defect, offering the best aesthetic and functional results. Computer design of the implant makes this process easier by providing an implant specific to each individual patient and defect. CLINICAL CASE: We report the case of a patient who was diagnosed with esthesioneuroblastoma and was treated with anterior craniofacial resection and radiotherapy. Osteomyelitis and osteoradionecrosis were consequent complications with loss of the cranial vault in the frontal region. The defect was reconstructed with a polyetheretherketone (PEEK) computer-designed implant based on the defect evaluated by computed tomography. Results obtained are shown below. CONCLUSIONS: The PEEK computer-designed implant is a safe and easy to use alternative with great adaptability to cranial vault defects.