An Institutional Experience of Fenestrated T-Bar Clip Use in The Management of Intracranial Aneurysms.

Surgical management of an intracranial aneurysm is mainly clipping. Various types of clips have been designed for complex, giant, and other aneurysms. Recently, the Yasargil-fenestrated T-bar clip has been introduced for the management of such complicated aneurysms. The literature regarding its efficacy, limitations, and method of application in complicated aneurysms is limited. We used the fenestrated T-bar clip in four patients of intracranial aneurysms - middle cerebral artery cortical branch aneurysm, anterior communicating artery partially thrombosed aneurysm, internal carotid artery paraclinoid simple aneurysm, and giant aneurysm. All aneurysms were successfully clipped with no residue or branch occlusion. The recovery of all patients was satisfactory. The fenestrated T-bar clip effectively reconstructed the parent artery and occluded the aneurysm in all cases. The application of this clip may be advantageous over the clip application in some uniquely challenging cases.

Sobredentadura retida por sistema barra-clipe: revisão de literatura / Overdenture retained by bar-clip system: literature review

Introdução: as overdentures são próteses totais removíveis, mucoimplanto-suportadas, estabilizadas por elementos instalados sobre raízes residuais e/ou sobre implantes. Uma variedade de sistemas de encaixe tem sido utilizada para suportar as sobredentaduras, dentre os quais os sistemas barra-clipe, bolas, magnetos e coroas telescópicas. Objetivo: avaliar, por meio de uma revisão de literatura, as sobredentaduras retidas por sistema barra-clipe, expondo um correto planejamento, bem como descrevendo protocolos de confecção de tais aparelhos. Métodos: foi realizada uma revisão de literatura nas bases de dados do Centro Latino-americano e do Caribe de Informações em Ciências da Saúde (LILACS), Medline, Bibliografia Brasileira de Odontologia (BBO), na biblioteca virtual (SCIELO), e no acervo de livros da Universidade de Passo Fundo/RS (UPF). Revisão de literatura: o sistema barra-clipe consiste de uma barra plástica para fundição (ou já em metal) e de um clipe de retenção. Em algumas situações, o sistema de encaixes por barra-clipe é mais indicado do que os demais sistemas, apresentando, todavia, limitações em determinados cenários clínicos. O sistema barra-clipe permite considerável retenção e estabilidade, resultando num restabelecimento da função mastigatória, maior segurança e grande satisfação do paciente. Considerações finais: a maior parte dos estudos mostrou uma melhora da qualidade de vida relacionada à saúde bucal dos pacientes após tratamento com overdenture em comparação com a prótese total removível convencional.

Introduction: overdentures are removable, muco-implantsupported, complete dentures, stabilized by elements installed on residual roots or implants. A variety of docking systems have been used to support overdentures, including bar-clip systems, balls, magnets and telescoping crowns. Objective: to evaluate, through a literature review, the overdentures retained by bar-clip system, exposing a correct planning, as well as describing protocols of making such devices. Methods: a literature review was carried out in the databases of the Latin American and Caribbean Center on Health Sciences Information (LILACS), Medline, Brazilian Dentistry Bibliography (BBO), the virtual library (SCIELO) and the collection of books from the University of Passo Fundo/RS (UPF). Literature Review: the bar-clip system consists of a plastic bar for casting or already metal and a retention clip. In some situations, the clip-on system is more suitable than other systems, although it has limitations in certain clinical scenarios. The bar-clip system allows considerable retention and stability, resulting in a restoration of the masticatory function, greater safety and great patient satisfaction. Final considerations: most of the studies showed an improvement in the quality of life related to the oral health of the patients after treatment with overdenture compared to the conventional total removable prosthesis.

Fenestrated T-bar Clips in Surgical Management of Internal Carotid Artery Aneurysms: Technical Note.

BACKGROUND: Using a conventional right-angled fenestrated clip for an internal carotid artery (ICA) aneurysm is potentially disadvantageous because of the worse surgical visibility during and after clip application, especially in tight surgical fields. METHODS: We report a case of ruptured posteromedially projecting ICA aneurysm treated using a right-angled fenestrated T-bar clip (Yasargil titanium clip, Aesculap AG & Co, Tuttlingen, Germany). A 52-year-old woman was admitted to our hospital with severe headache. Three-dimensional computed tomography angiography showed a saccular aneurysm arising from the left, unusually short ICA, located proximal to the anterior choroidal artery. The right-angled fenestrated T-bar clip (blade length, 5 mm) was applied across the ICA, followed by reconstruction of the ICA wall with preservation of the anterior choroidal artery and simultaneous obliteration of the aneurysm. RESULTS: The key characteristic of the fenestrated T-bar clip is that the fenestrated portion of the clip is connected to the center of the blades. The tips of the blades on both sides are thus clearly visible during clip application. CONCLUSIONS: Application of the T-bar clip allows the surgeon to perform clip ligation of a posteromedially projecting ICA aneurysm while preserving the adjacent perforating artery.

Stress analysis of mandibular implant overdenture with locator and bar/clip attachment: Comparative study with differences in the denture base length.

PURPOSE: The design of the attachment must provide an optimum stress distribution around the implant. In this study, for implant overdentures with a bar/clip attachment or a locator attachment, the stress transmitted to the implant in accordance with the change in the denture base length and the vertical pressure was measured and analyzed. MATERIALS AND METHODS: Test model was created with epoxy resin. The strain gauges made a tight contact with implant surfaces. A universal testing machine was used to exert a vertical pressure on the mandibular implant overdenture and the strain rate of the implants was measured. RESULTS: Means and standard deviations of the maximum micro-deformation rates were determined. 1) Locator attachment: The implants on the working side generally showed higher strain than those on the non-working side. Tensile force was observed on the mesial surface of the implant on the working side, and the compressive force was applied to the buccal surface and on the surfaces of the implant on the non-working side. 2) Bar/clip attachment: The implants on the both non-working and working sides showed high strain; all surfaces except the mesial surface of the implant on the non-working side showed a compressive force. CONCLUSION: To minimize the strain on implants in mandibular implant overdentures, the attachment of the implant should be carefully selected and the denture base should be extended as much as possible.

Stress analysis of mandibular implant overdenture with locator and bar/clip attachment: Comparative study with differences in the denture base length

PURPOSE: The design of the attachment must provide an optimum stress distribution around the implant. In this study, for implant overdentures with a bar/clip attachment or a locator attachment, the stress transmitted to the implant in accordance with the change in the denture base length and the vertical pressure was measured and analyzed. MATERIALS AND METHODS: Test model was created with epoxy resin. The strain gauges made a tight contact with implant surfaces. A universal testing machine was used to exert a vertical pressure on the mandibular implant overdenture and the strain rate of the implants was measured. RESULTS: Means and standard deviations of the maximum micro-deformation rates were determined. 1) Locator attachment: The implants on the working side generally showed higher strain than those on the non-working side. Tensile force was observed on the mesial surface of the implant on the working side, and the compressive force was applied to the buccal surface and on the surfaces of the implant on the non-working side. 2) Bar/clip attachment: The implants on the both non-working and working sides showed high strain; all surfaces except the mesial surface of the implant on the non-working side showed a compressive force. CONCLUSION: To minimize the strain on implants in mandibular implant overdentures, the attachment of the implant should be carefully selected and the denture base should be extended as much as possible.

Stress distribution patterns of implant supported overdentures-analog versus finite element analysis: A comparative in-vitro study.

AIMS AND OBJECTIVES: The aim of this study was to asses & compare the load transfer characteristics of Ball/O-ring and Bar/Clip attachment systems in implant supported overdentures using analog and finite element analysis models. METHODOLOGY: For the analog part of the study, castable bar was used for the bar and clip attachment and a metallic housing with a rubber O-ring component was used for the ball/O-ring attachment. The stress on the implant surface was measured using the strain-gauge technique. For the finite element analysis, the model were fabricated and load applications were done in a similar manner as in analog study. RESULTS: The difference between both the attachment systems was found to be statistically significant (P<0.001). CONCLUSION: Ball/O-ring attachment system transmitted lesser amount of stresses to the implants on the non-loading side, as compared to the Bar-Clip attachment system. When overall stress distribution is compared, the Bar-Clip attachment seems to perform better than the Ball/O-ring attachment, because the force was distributed better.