Confección de prótesis de carga inmediata mediante barras articuladas: componentes, modo de uso y longitud de la barra en función de la localización / Fabrication of immediately loaded prostheses using articulated bars: components, method of use and bar length depending on the location

En la implantología actual, la confección de prótesis de carga inmediata se ha convertido en un procedi-miento de rutina. Contar con elementos pre-formados con un correcto ajuste al implante o transepitelial so-bre el que se trabaja, minimiza el tiempo de trabajo sin renunciar a la eficiencia. En el presente trabajo se muestran elementos preformados articulados para la realización de prótesis de carga inmediata y su forma de uso, así como un análisis biomecánico de las estructuras para conocer su repercusión en las distintas fuerzas recibidas durante la masticación. Resultados: Al aplicar la carga en la zona central de la barra (paralela a los implantes), la tensión máxima recibida en la zona correspondiente al extremo de la barra sufre variaciones importantes, desde 128 Mpa en la longitud de 13 mm hasta un máximo de 391 Mpa (megapascales) en la longitud de 5 mm, siendo la ten-sión máxima, media para todas las medidas, de 242 Mpa (+/-96,76). En el ensayo de las diferentes medi-das de la barra se observa también una tensión cre-ciente para longitudes de barra a partir de 7 mm, al aplicar la tensión en la zona media de la estructura, por lo que longitudes entre 5 y 7 mm pueden consi-derarse prácticamente con la misma distribución de tensiones hacia los extremos y en la zona de unión. En conclusión, las barras articuladas son un elemento de confección de prótesis provisionales de carga in-mediata de gran utilidad, que pueden confeccionarse de forma rápida y generan un comportamiento bio-mecánico predecible (AU)

In current implantology, the fabrication of immediately loaded prostheses has become a routine procedure. Being able to have pre-formed elements with a correct fit to the implant or transepithelial on which we are working minimizes working time without sacrificing efficiency. Material and methods: We show articulated preformed elements for immediate loading prostheses and how they are used, as well as a biomechanical analysis of the structures to determine their repercussion on the different forces received during mastication. Results: When the load is applied in the central area of the bar (parallel to the implants) the maximum stress received in the area corresponding to the end of the bar undergoes significant variations, from 128 Mpa in the 13 mm length to a maximum of 391 Mpa in the 5 mm length, the average maximum stress for all the measurements being 242 Mpa (+/-96.76). In the test of the different bar sizes we can also observe an increasing stress for bar lengths from 7 mm onwards when applying the stress in the middle zone of the structure, so that lengths between 5 and 7 mm can be considered to have practically the same stress distribution towards the ends and in the joint zone. Conclusions: Hinged bars are a very useful fabrication element for immediately loaded provisional prostheses, which can be fabricated quickly and generate a predictable biomechanical behavior (AU)

Tratamiento de la periimplantitis. Explantación atraumática y nuevo tratamiento con implantes. Reversibilidad de la oseointegración / Treatment of peri-implantitis. Atraumatic explantation and new treatment with implants. Reversibility of osseointegration

La periimplantitis se define como la patología inflamatoria e irreversible que afecta al hueso periimplantario y le hace perder soporte y función al implante según la definición del European Workshop on Periodontology (EWOP). La prevalencia estimada de la periimplantitis es de 28 a 77%. Los diferentes protocolos de abordaje de la periimplantitis nos ofrecen diversas posibilidades: destoxificación de la superficie y regeneración, limpieza mecánica y resección del tejido inflamado, extracción del implante, entre otros. El principal problema de los tratamientos regenerativos es limpiar y desintoxicar correctamente la superficie del implante expuesto, ya que al tratarse de superficies generalmente muy rugosas, las bacterias del medio bucal las colonizan con mucha facilidad y es prácticamente imposible eliminar por completo el biofilm. El protocolo de tratamiento para la periimplantitis se basa en un algoritmo de tratamiento, en el que se retiran los implantes gravemente afectados por periimplantitis de forma atraumática, lo cual garantiza la conservación del lecho al 100% al no retirarse volumen óseo, y cuándo deben utilizarse las trefinas, pues las que se utilizan en el protocolo únicamente rompen la unión ósea de los primeros milímetros sin retirarlo. En el siguiente caso clínico mostramos el retratamiento de un caso de periimplantitis en el que se ha realizado una nueva rehabilitación implantosoportada (AU)

Periimplantitis is defined as the inflammatory and irreversible pathology that affects the peri-implantary bone and causes it to lose support and function to the implant as defined by the European Workshop on Periodontology (EWOP). The estimated prevalence of periimplantitis figures ranging from 28 to 77%. The different protocols for approaching periimplantitis offer different possibilities: detoxification of the surface and re-generation, mechanical cleaning and resection of inflamed tissue and extraction of the implant mainly. The main problem with regenerative treatments is to correctly clean and detoxify the surface of the exposed implant, since as these are generally highly rough surfaces, bacteria in the oral environment colonise them very easily and it is practically impossible to completely eliminate the biofilm. This treatment algorithm, in which implants severely affected by periimplantitis are removed atraumatically, guarantees the conservation of the bed at 100% since no bone volume is removed and trephines must be used, since those used in the protocol only break the bone union of the first few millimetres, without removing it. In the following clinical case, we show the re-treatment of a case of peri-implantitis where a new implant-supported rehabilitation has been performed (AU)

Autologous platelet-rich gel for facial rejuvenation and wrinkle amelioration: A pilot study.

BACKGROUND: The demand for safe and minimally invasive soft tissue augmentation procedures has increased. Recently, a novel injectable gel based on the autologous platelet rich in growth factor (PRGF) technology has been developed to provide long-term shape and volume stability. It can be customized into low (LVG) or high viscosity (HVG) gel forms to meet different dermatological requirements. OBJECTIVES: The mechanical and biological properties of both gel forms have been evaluated. The clinical efficacy and safety of this autologous procedure were also evaluated. METHODS: Growth factor content and biomechanical properties of both gel forms were determined. The in vitro biological capacity on human dermal fibroblasts proliferation was assessed. Clinical performance analysis over ten patients was evaluated by standardized macrophotographs, 3D topographic images, and ultrasound analysis over periocular and nasolabial areas. RESULTS: Both gel types showed similar growth factor concentration. HVG showed a higher stiffness profile indicating its suitability for deeper tissue defect viscosupplementation while LVG showed optimal rheologic characteristics for superficial volumization. Both gels showed a noticeable biostability after catalytic enzyme degradation. Both forms significantly increased the mitogenic activity of dermal fibroblasts. All patients referred to be highly satisfied and presented optimal clinical results after one month. Overall clinical improvement was maintained for 16 weeks. At the end of the study, the ultrasound examination revealed a cutaneous regenerative effect. No adverse events occurred. CONCLUSIONS: This preliminary study suggests that autologous platelet gels have desirable mechanical and bioactive properties and allows moderate wrinkle reduction and efficient facial volume reposition with natural results.

Orthokeratinized odontogenic cyst: a report of three clinical cases.

The orthokeratinized odontogenic cyst (OOC) is a rare developmental odontogenic cyst that has been considered as a variant of the keratocystic odontogenic tumour (KCOT) until Wright (1981) defined it as a different entity. Surgery is the usual treatment, and recurrence or association with Gorlin-Goltz syndrome has rarely been described. In this report, we presented three cases of this pathology, and we review the principal clinical, histological, radiological, and therapeutic aspects. Case 1. A 73-year-old female presents with a slight swelling on the right mandible, associated with an unilocular well-defined radiolucent lesion. Case 2. A 27-year-old female presents with a painful mandibular swelling associated with an unilocular radiolucent lesion posterior to the 4.8. Case 3. A 61-year-old male was casually detected presents with an unilocular radiolucent lesion distal to the 4.8. Conclusion. The OOC is a specific odontogenic clinicopathological entity that should be differentiated from the KCOT as it presents a completely different biological behaviour.

La utilización de los factores de crecimiento plasmáticos en cirugía oral, maxilofacial y periodoncia [P.R.G.F.] / The use of plasma rich in growth factors in oral and maxillofacial surgery and periodontics [P.R.G.F.]

Se presenta un protocolo para la obtención de un plasma autólogo rico en factores de crecimiento (P.R.G.F) obtenido de forma ambulatoria así como diferentes técnicas de aplicación, para obtener un coágulo rico en factores de crecimiento. Algunas de las ventajas observadas de su uso, son el favorecer la epitelización de una herida, acelerar y favorecer la neoformación ósea, compactar y retener los injertos, relleno de un alveolo post-extracción, ser un excelente osteoconductor y un largo etcetera (AU)