The effect of a novel pillar surface morphology and material composition demonstrates uniform osseointegration.

Long-term survival of orthopedic implants requires a strong and compliant interface between the implant and surrounding bone. This paper further explores the in-vivo response to a novel, macro-scale osseointegration surface morphology. In this study, we examine the effects of material composition on osseointegration in relation to the controlled surface geometry.

In-Vivo response to a novel pillared surface morphology for osseointegration in an ovine model.

Primary stability and secondary fixation of orthopedic implants to bony tissues are important for healing and long-term functionality. Load sharing and stress transfer are key requirements of an effective implant/tissue interface. This paper presents a novel, macro-scale osseointegration surface morphology which addresses the implant/tissue interface from both the biologic as well as biomechanical perspective.

Five-Year Safety Data for More than 55,000 Subjects following Breast Implantation: Comparison of Rare Adverse Event Rates with Silicone Implants versus National Norms and Saline Implants.

Background: The U.S. Food and Drug Administration has required postapproval studies of silicone breast implants to evaluate the incidence of rare adverse events over 10 years after implantation.

Natrelle Silicone Breast Implant Follow-Up Study: Demographics, Lifestyle, and Surgical Characteristics of More Than 50,000 Augmentation Subjects.

Background: A large, multicenter, 10-year observational study is being conducted to compare the long-term safety and effectiveness of Natrelle silicone breast implants with saline implants or national norms. Study baseline data and surgical characteristics are reported here.

Methods: Women seeking primary augmentation, revision-augmentation, primary reconstruction, or revision-reconstruction participated.

Natrelle Silicone Breast Implant Follow-up Study: Demographics, Lifestyle, and Surgical Characteristics of More Than 5000 Reconstruction Subjects.

Background: A large, multicenter, 10-year observational study is comparing the long-term safety and effectiveness of Natrelle silicone breast implants versus saline implants or national norms.

Methods: Women who underwent primary augmentation, revision-augmentation, primary reconstruction, or revision-reconstruction were invited to participate. Enrolled subjects had completed surgery and received one implant or matching implants.

[Standardized computer-based documentation system for diagnoses and medical performance in orthopedics and traumatology. Development and initial application].

Introduction: Increasing demands on quality assurance und medical performance documentation require an immediate and evaluable documentation in the outpatients' department. Presentation of a new computer-based diagnostic system for reporting and medical performance documentation.

Methods: Development and initial application of the system in three big orthopedical or traumatological hospitals.

Development of a standardised computer-based documentation system for diagnoses and medical performance in orthopeadics/traumatology.

Introduction: Increasing demands on quality assurance und medical performance documentation require an immedate and evaluable documentation in the outpatients' department. Presentation of a new computer-based diagnostic system for reporting and medical performance documentation.

Methods: Development and initial application of the system in three big orthopeadical or traumatological hospitals.

Investigation of silicone oil and fumed silica in an adjuvant animal model.

Human adjuvant disease is the label given to a syndrome that resembles a connective tissue disease such as scleroderma and that has been hypothesized to follow augmentation mammoplasty with silicone gel implants or silicone with adulerants. To date, there is no proof that pure silicone is the cause of these symptoms. The cases presented in the literature suggest a comparison to the events seen in the rat adjuvant arthritis model.

Pillared-surface microstructure and soft-tissue implants: effect of implant site and fixation.

Previous work with subcutaneous implants in a rat animal model has shown that pillarlike surface microstructure will reduce fibrosis and enhance blood vessel approximation to the implant surface when compared with nontextured controls. This study was designed to determine the effect of microtissue anatomy and implant site on the observed response, as well as the effect of implant fixation. The lateral posterior sites were found to contain a fat pad which produced a dramatically reduced fibrosis for the micro-structured implants compared with smooth controls.

Histologic comparison of breast implant shells with smooth, foam, and pillar microstructuring in a rat model from 1 day to 6 months.

The purpose of this study was to determine the soft-tissue response to silicone breast implants with different surface morphologies and to correlate implant microtexturing with capsular formation. Using a rat model, we inserted breast implants having three types of shells: micropillared, silicone foam, and smooth silicone (control). We used 96 adult male Sprague-Dawley rats weighing between 250 and 300 gm.

Placement of a feeding button ("one-step button") as the initial procedure.

The procedure of choice for enteral feeding access is now percutaneous endoscopic gastrostomy (PEG). Standard PEG tubes have the disadvantages of clogging, stomal enlargement, and external bulkiness. Button replacement tubes can covert the more cumbersome PEG tubes to low external profile devices.

Development of an implantable drug delivery catheter.

A microtextured, pillared drug delivery system has been designed and tested in rabbits. This model has allowed for the calculation of the mass transport rate indicating after a 4 week time period a pillar device's mass transport rate K1 [min-1] is K1p 1.54 x 10(-2) in contrast to the smooth control which is K1C .

Analysis of the soft-tissue response to components used in the manufacture of breast implants: rat animal model.

The implant-tissue response to the silicone gel mammary prosthesis requires a more thorough evaluation in light of recent concerns related to human connective-tissue diseases, contracture, infection, and neoplasia. The silicone prosthesis is not a homogeneous implant but is a milieu of various silicone chemistries. Silicone polymer precursors and prosthesis components (silicone shells, shells extracted of their low-molecular-weight components, silica-free silicone, silicone oil, fumed silica, and silicone extract) were implanted subcutaneously using a nonhemorrhagic technique into the backs of Lew/SsN rats (n = 90), two implants per rat, for periods of 7, 14, 28, 56, and 90 days for a total of 6 implants per material per time period.

Microvascular A-V shunts and the growth of autologous tissue flaps in Millipore chambers.

An animal model was developed using the male Sprague-Dawley rat to establish a protocol and design criteria for the growth of autologous tissue based on a microvascular pedicle. It became apparent that growth within the chamber depended heavily on membrane porosity and the presence of the microarteriovenous shunt. Different membrane porosities ranging from 0.

The use of coralline hydroxyapatite in a "biocomposite" free flap.

An animal model was developed to determine the feasibility of vascularizing a porous biomaterial and transferring it as part of a free flap to a recipient site with enhanced resistance to infection due to the maintenance of a blood supply. To that end, the experiment was divided into three stages. Stage 1 compared the soft-tissue response of Interpore-200 to Interpore-500, both continuously porous hydroxyapatite materials implanted beneath the panniculus carnosus of the male Sprague-Dawley rat.

In vitro and in vivo testing of an electrocatalytic glucose sensor.

A prerequisite for the development of an implantable artificial pancreas is the availability of a stable, long-life glucose sensor. Platinum (Pt) catalyzed electrodes have been demonstrated in vitro to show high sensitivity to glucose and long cycle life but are more sensitive to co-reactants compared with enzymatic methods. The authors developed a special data processing method (compensated net charge ratio, or CNCR) in which the measured electrode response is very sensitive to glucose, completely insensitive to urea, and only moderately sensitive to amino acids.

Natural-Y Même polyurethane versus smooth silicone: analysis of the soft-tissue interaction from 3 days to 1 year in the rat animal model.

The polyurethane foam-covered breast prosthesis is experiencing increased clinical use. The polyurethane is felt to be responsible for altering capsule formation and reducing the contracture rate. This study characterizes the soft-tissue response to the Natural-Y Même polyurethane foam versus smooth silicone in a rat model.

Electrocatalytic glucose sensor.

High surface area platinum subjected to the appropriate electrical potential cycling regimes exhibits considerable electrocatalytic activity towards glucose oxidation. We have developed a special data processing method, the compensated net charge (CNC) method, to take advantage of the electrocatalytic activity of platinum. This method involves the determination of the net oxidation charge during one complete cycle of a cyclic voltammogram applied to the platinum electrode in a potentiodynamic mode.

Expanded polytetrafluoroethylene as a microvascular graft: a study of four fibril lengths.

The utility for a prosthetic microvascular graft is well demonstrated, but previous studies have been inconclusive. Expanded polytetrafluoroethylene (Gore-Tex) has been most widely tested as a prosthetic graft. Polytetrafluoroethylene is composed of transverse nodules connected by long fibrils.

The gastrostomy "button"--a simple, skin-level, nonrefluxing device for long-term enteral feedings.

In an effort to eliminate the common problems associated with gastrostomy tubes in children, we developed a silicone rubber gastrostomy "button" designed to replace the standard long latex tube. Easily inserted and self-retaining, the device remains practically flush with the skin. The intragastric portion is similar to a dePezzer catheter, and a one-way valve prevents reflux of gastric contents.

Effect of polyurethane morphology on blood coagulation.

A series of polyurethanes based on the hard segment MDI and soft segment PTMG were synthesized. The molecular weight of the PTMG was 730, 1000, and 2000, and ethylene diamine was used as chain extender. The fabrication process was varied so as to achieve the maximum disorder (nonequilibrium state) and maximum order, fully annealed.

Surface characteristics of the cardiac prostheses in vivo.

The pseudoneointima (PNI) deposited onto a cardiac prosthesis surface reflects many factors of biocompatibility, surface morphology, flow distribution, design, animal's physiological condition, and duration. In the evaluation of any prosthesis, the PNI is one of the prime considerations from both material and functional standpoints. Historically, Dacron fabric has been used as an internal lining for cardiac prostheses.

Application of aldehyde treatments to cardiovascular devices.

Biolized natural and synthetic materials represent a new class of materials. Aldehyde treatment of natural tissue creates cross-links in the collagen molecules while retaining mechanical strength and collagen structure. Synthetic polymers can also be biolized by the addition of protein and aldehyde treatment.