What is DAC®
DAC® is a Class III, EC marked medical device.
DAC® is composed of two bioresorbable polymers: Hyaluronic acid and Poly-lactic acid.
It is produced in the form of a powder that, to obtain the hydrogel formulation, must be hydrated with water for preparations that are injectable alone, or in solution with an antibiotic. The indication is the prevention of peri-implant infection.
Said prevention is obtained by coating the implant components or internal fixation devices with DAC® hydrogel before implant insertion in the operating theatre in order to create a protective barrier against bacterial adherence.
Hyaluronic acid (HA)
HA is a natural polysaccharide present in all living organisms. In the human body, it constitutes the main component of the extracellular matrix (ECM) of connective tissue. Its molecule has an identical chemical structure in bacteria, animals, and human beings. Since it is chemically identical in all species and all types of tissue, hyaluronic acid is characterised by the fact that it is completely biocompatible.
Most of the cells in the body are able to synthesize hyaluronic acid during certain stages of their own life cycle. This involves its function in various basic biological processes.
HA does not contain organism-specific protein and therefore it does not trigger immune response during implanting. This lack of immunogenicity makes HA an interesting component for the designing of new biomaterials (1).
Materials coated with HA show limited bacterial biofilm growth (2). Hyaluronic acid that was originally used as a hydrophilic polymer to coat polyurethane catheters (3) has shown reduced adherence to S. epidermidis (4, 5). Surfaces coated with sulphated hyaluronic acid show a marked reduction in adherence and bacterial growth compared to non-coated surfaces (6).
Poly-lactic acid (PLA)
Poly-lactic acid (PLA) is a biodegradable and bio absorbable synthetic polymer obtained from renewable sources and in particular, from corn or other cereals, through the bacterial fermentation and polymerisation of lactic acid.
Not only does this biomaterial come from natural materials, it is entirely biodegradable, and can be converted naturally to CO2 and H2O. It is one of the few polymers in which the stereochemical structure can be easily modified by polymerising a controlled blend of L or D isomers with high molecular weight, amorphous or crystalline polymers that have been GRAS-listed (Generally Recognized As Safe).
PDLLA and PLLA-based medical devices are widely used in medical fields: for example, as suture thread, especially in orthopaedic, maxillofacial and spine surgery, in the form of plates, pins, screws, etc., sometimes replacing metal medical devices (7). Recently it has been employed as a long-term filler in plastic surgery.