Safety of bioabsorbable implants in vitro

The Journal of the American Academy of Orthopaedic Surgeons

The use of bioabsorbable implants in orthopaedic surgical procedures is becoming more frequent. Advances in polymer science have allowed the production of implants with the mechanical strength necessary for such procedures. Bioabsorbable materials have been utilized for the fixation of fractures as well as for soft-tissue fixation. These implants offer the advantages of gradual load transfer to the healing tissue, reduced need for hardware removal, and radiolucency, which facilitates postoperative radiographic evaluation. Reported complications with the use of these materials include sterile sinus tract formation, osteolysis, synovitis, and hypertrophic fibrous encapsulation. Further study is required to determine the clinical situations in which these materials are of most benefit.

Bioabsorbable materials are more commonly used now days in orthopaedic surgeries. Bioabsorbable implants for fracture fixation, and meniscal repair. These implants provide the advantages of gradual load transfer to the healing tissue, reduced need for implant removal, and radiolucency, which facilitates postoperative radiographic evaluation and no hinderance in second surgery. These also carries disadvantages like, more expensive, having less strength than metals, tissue reactions including mild fluid accumulation, painful erythematous fluctuating papule, sterile sinus tract formation, osteolysis, synovitis, and hypertrophic fibrous encapsulation. We advocate more researches to be carried out for the best suitability of these materials in orthopaedic surgeries.

Journal of Applied Biomaterials, 1993

Acta Orthopaedica et Traumatologica Turcica, 2020

With the evolution of medical science, research on implant improvement has concentrated on biodegradable plastic materials (1, 2). The application of biopolymers has many advantages over most other materials, such as better biocompatibility and biodegradability and being environmentally friendly (3). Biodegradable polymers are being used in many areas of medicine, such as drug delivery systems, tissue engineering, and other applications (2).

2015

Title: Safety of bioabsorbable implants in vitro Authors: Mehmet Isyar ([email protected]) Ibrahim Yilmaz ([email protected]) Gurdal Nusran ([email protected]) Olcay Guler ([email protected]) Sercan Yalcin ([email protected]) Mahir Mahirogullari ([email protected]) Version: 1 Date: 20 Oct 2015 Author’s response to reviews: Manuscript Number: BSUR-D-15-00053 Manuscript Title: Safety of bioabsorbable implants in vitro

Biomaterials, 2005

Fracture healing can be stimulated by exogenous application of growth factors. Using porcine and rat models the efficacy of locally delivered IGF-I and TGF-b1 from an implant coating has been demonstrated. A thin and biomechanical stable biodegradable poly(D,L-lactide) was used to coat implants and serve as a drug carrier. Due to reports of possible foreign body reactions caused by polymer materials in orthopedic surgery, this study investigated the biocompatibility of the polylactide implant coating and the locally released growth factors during the time course of rat tibial fracture healing (days 5, 10, 15, and 28 after fracture). Monocytes/macrophages and osteoclast were detected using an monoclonal antibody against ED1 (comparable to CD68 in mice and human). The antibody ED1 stains monocytes, macrophages and osteoclast in the bone marrow and in the newly formed fracture callus. A moderate density of the monocytes/macrophages was seen in the proximal part of the medullary canal, but almost no cells were detectable in the region distal to the fracture. The amount of stained cells increased during the observation time with a maximum at days 10 and 15 followed by a decrease at day 28. No differences were detectable between the investigated groups from day 5 to 15 post fracture indicating, that the used poly(D,L-lactide) or the incorporated growth factors do not evoke an elevated immunological response compared to the uncoated titanium implant at the investigated time points. A significantly higher amount of ED1 positive cells was measured 28 days after fracture in the control group compared to the groups with the coated implants.

British Journal of Oral & Maxillofacial Surgery, 1989

Poly (L-lactide), a polymer of lactic acid (PLLA), with an extremely high molecular weight (l('Iv up to l xl06) has been synthesised under strictly controlled conditions resulting in a new microporous material with excellent mechanical properties. Bone-plates and screws machined from PLLA were used for fixation of two artificial mandibular fractures in sheep effected by a specially designed bone clamp. Fracture healing was uneventful without visible callus formation. Plates and screws of PLLA gave good stability over a sufficiently long period to enable normal fracture healing. Application in humans seems to be justified.

Journal of applied biomaterials & biomechanics (JABB)

Biocybernetics and Biomedical Engineering, 2020

A biologically-validated biodegradable material must comfortably stay in the physiological environment it is placed in, before finally disappearing over the intended period of time with adequate rates of degradation. The primary objective and utility of such a material is to eliminate the requirement of secondary surgery in applications involving bone implants. In recent decades, biodegradable alloys have exhibited enhanced biocompatibility, and improved mechanical and biodegradation properties. This has generated renewed interest in the design of bone implants made up of such materials that can successfully support fractured bone till the culmination of the healing process. However, striking a balance between two seemingly conflicting requirements, namely-sustaining the strength of the implant till the bone acquires the desired strength of its own, and allowing the implant to keep losing strength with its gradual degradationmay be rather complex. To manage this, different healing phases and the associated bone-biodegradable implant interface mechanobiology needs to be focused upon. An adequate and/or optimal design of the implant is based on mechanical properties, degradation rates of implant and bone-biodegradable implant interface interactivity. This review mainly focuses on bone-biodegradable implant interface with due consideration accorded to the mechanical properties, degradation rates and healing process in a standard duration.

Coatings

In orthopedics, bone fixation imposes the use of implants in almost all cases. Over time, the materials used for the implant have evolved from inert materials to those that mimic the morphology of the bone. Therefore, bioabsorbable, biocompatible, and bioactive materials have emerged. Our study aimed to review the main types of implant materials used in orthopedics and present their advantages and drawbacks. We have searched for the pros and cons of the various types of material in the literature from over the last twenty years. The studied data show that consecrated metal alloys, still widely used, can be successfully replaced by new types of polymers. The data from the literature show that, by manipulating their composition, the polymeric compounds can simulate the structure of the different layers of human bone, while preserving its mechanical characteristics. In addition, manipulation of the polymer composition can provide the initiation of desired cellular responses. Among the ...