Search results for "Prosthesis"
showing 10 items of 719 documents
SIMPLE, SAFE AND EASY TECHNIQUE TO ENSURE THE CORRECT LENGTH OF ARTIFICIAL CHORDAE IN MITRAL VALVE REPAIR.
2007
Replacement of diseased chordae with Gore-Tex sutures (W. L. Gore & Assoc, Flagstaff, AZ) in patients with degenerative mitral valve insufficiency has become a standard technique used by surgeons in mitral valve repair with good long-term results. Nevertheless, determining the correct length of the artificial chordae has remained problematic. Although various procedures have been previously published, in this article we describe our approach used to achieve an accurate chordal height adjustment.
Transgastric imaging-The key to successful periprocedural TEE guiding for edge-to-edge repair of the tricuspid valve.
2021
Intraprocedural transesophageal echocardiography (TEE) guidance plays an essential role in transcatheter repair therapy of the tricuspid valve (TV). So far, several different imaging concepts are in use. We propose an imaging protocol that fully addresses the morphological complexity of the TV and further offers efficacious workarounds for the frequently occurring restrictions of TV imaging in edge-to-edge repair of the TV. As a tertiary referral center with a large experience of more than 250 cases of transcatheter edge-to-edge repair (TEER) of the TV performed at the Heart Valve Center in Mainz/Germany, we have constantly adapted our peri-interventional echocardiographic approach to accom…
From medical data to simple virtual mock-up of scapulo-humeral joint
2008
The surgical operations of shoulder joint are guided by various principles: osteosynthesis in the case of fracture, osteotomy in order to correct a deformation or to modify the functioning of the joint, or implementation of articular prosthesis. At the end of the twentieth century, many innovations in the domains of biomechanics and orthopedic surgery have been performed. Nevertheless, theoretical and practical problems may appear during the operation (visual field of surgeon is very limited, quality and shape of the bone is variable depending on the patient). Biomechanical criteria of success are defined for each intervention. For example, the installation with success of prosthetic implan…
ICR in human cadaveric specimens: An essential parameter to consider in a new lumbar disc prosthesis design.
2020
[EN] Study design Biomechanical study in cadaveric specimens. Background The commercially available lumbar disc prostheses do not reproduce the intact disc's Instantaneous centre of Rotation (ICR), thus inducing an overload on adjacent anatomical structures, promoting secondary degeneration. Aim To examine biomechanical testing of cadaveric lumbar spine specimens in order to evaluate and define the ICR of intact lumbar discs. Material and Methods Twelve cold preserved fresh human cadaveric lumbosacral spine specimens were subjected to computerized tomography (CT), magnetic resonance imaging (MRI) and biomechanical testing. Kinematic studies were performed to analyse range of movements in or…
Immediate and flapless implant insertion and provisionalization using autogenous bone grafts in the esthetic zone: 5-year results.
2017
Objectives As the 2-year results for immediately inserted and provisionalized implants have been reported, it remained an open issue, whether the initially high success rates and the esthetic outcome remain stable for longer observation periods. Therefore, this prospective study examines the 5-year hard and soft tissue changes at implants placed in the anterior maxilla. Material and methods Meanwhile, 37 microthreaded implants were placed in 21 patients into extraction sockets with and without facial bone deficiencies by a flapless approach. Facial gaps and bony defects were grafted with autogenous bone chips. The implants were immediately provisionalized. The primary outcome parameters wer…
Immediate loading with fixed full-arch prostheses in the maxilla: review of the literature
2014
Objectives: To critically review the evidence-based literature on immediate loading of implants with fixed full- arch prostheses in the maxilla to determine 1) currently recommended performance criteria and 2) the outcomes that can be expected with this procedure. Study Desing: Studies from 2001 to 2011 on immediate loading with fixed full-arch maxillary prostheses were reviewed. Clinical series with at least 5 patients and 12 months of follow-up were included. Case reports, studies with missing data and repeatedly published studies were excluded. In each study the following was assessed: type of study, implant type, number of patients, number of implants, number of implants per patient, us…
Volumetric variation of peri-implant soft tissues in convergent collar implants and crowns using the biologically oriented preparation technique (BOP…
2018
Background To evaluate the changes in the peri-implant soft tissues of convergent collar implants with biologically oriented preparation technique (BOPT) crowns, 10 months after loading. Material and Methods A pilot study was carried out from January 2016 to October 2017 involving 14 patients with one or two implants in the posterior mandibular sector. A total of 32 convergent collar implants were placed using a non-submerged protocol. Three months later the provisional cemented crowns were fitted using the BOPT approach with the finish line 1-1.5 mm below the gingival margin, simulating coronal emergence of a natural tooth. The soft tissue changes were measured with an intraoral scanner at…
Immediate Loading with Fixed Full-Arch Prosthesis in the Edentulous Patient: Treatment Protocol
2019
Immediate loading is basically a prosthetic concept. However, the surgical implantological planning is very important to ensure a primary stability in the total edentulous patient. This characteristic is crucial to allow immediate loading in this type of patients. For the first time, the incisional design has allowed the clinician to overview about the surgical side. Later, maybe, the bone will need an osteoplasty to regularize possible bone defects. To ensure primary stability, it can use methods to enhance primary stability as undersized drilling technique and use of osteotomes and bi-cortical anchorage implants. There are two main protocols to obtain temporary immediate loading full-arch…
Design characteristics, primary stability and risk of fracture of orthodontic mini-implants: Pilot scan electron microscope and mechanical studies
2013
Objectives: Orthodontic mini-implants (OMIs) are increasingly used in orthodontics but can fail for various reasons. This study investigates the effects of OMI design characteristics on the mechanical properties in artificial bone. Material and Methods: Twelve self-drilling OMIs (2 small, 6 medium, 4 large) from 8 manufacturers were tested for their primary stability in simulated medium-high cancellous bone and the risk to fracture in high-density methacrylate blocks. For the assessments of the maximum insertion torque (IT) and torsional fracture (TF) 5 of each OMI were used and for the pull-out strength (POS) 10. The OMIs were inserted with a torque screwdriver (12 sec/360°) until the bott…
Locking Reconstruction Double Plating of Distal Humeral Fractures: How Many Screws in the Distal Ulnar Column Segment in A3 Fracture Provide Superior…
2009
Objectives: Two 90-degree configurations of locking reconstruction plates with different numbers of screws in the distal ulnar column segment of distal extra-articular humeral fractures with metaphyseal comminution (A3) were biomechanically investigated. Methods: Eight pairs of fresh-frozen human humeri were used. For paired comparison, the humeri were divided into 2 randomized groups. In both groups, double-plate osteosyntheses with locking reconstruction plates were performed in 90-degree configurations. In group 1, the posteriorly placed radial column plate exceeded the capitellum and the ulnar column plate extended into the ulnar sulcus. The ulnar plate was molded around the medial epic…