Biomedical Engineering Reference
In-Depth Information
however, we must remember that those trials are conducted on glass
disk with artiicial environment without the inluence of hormones,
nervous system and blood low. It so happens that
in vivo
studies not
always conirm the
in vitro
results. Therefore, it is essential to inish
all the
in vivo
models to initiate the clinical trials.
2.3
Characteristics of the
Stomatognathic System
Within the stomatognathic system, we can distinguish two
environments. One of them is composed of hard and soft tissues
as well as body luids. From the biophysical point of view, tissue
environment has the characteristics of electrochemical membrane.
Moreover, it possesses membranes and membrane potentials, which
are responsible for ionoselective effect and metabolism. Body luids,
on the contrary, are characterized by ion conductivity. Into this
environment, due to a loss of tissue, biomaterials are introduced to
repair and to bring back the function of the system. Mostly, these
are metal implants or screws or bone materials used in maxillo-
facial surgery, implantology, and prosthetics. The osseointegrated
interface depends on the physical and biophysical characteristics of
the surrounding environment and the physicochemical properties of
the surface of the implant.
The second environment is composed of the oral cavity, to which
materials are introduced by preventive dentistry, prosthetics, and
orthodontics. Those implants have hybrid composite structure,
where the core is composed of metal, an electric conductor. However,
the surface of the implant is coated by polymer or bioceramics, which
has the characteristics of an insulator or a semiconductor. Moreover,
the whole structure of the biomaterial forms a complex system,
which is an essential issue for the development of corrosion or
biodegradation of implants. Some of the prosthetic reconstructions
are localized in both environments.
Referring to the complexity of the system, biochemical,
biomechanical, and bioelectronic factors should be considered, which
are undoubtedly connected to the ongoing metabolic, bacteriological,
and immunological processes within the system.
Microlora of the oral cavity is speciic: containing unique
molecular, structural, and microbial characteristics, each of the
body sites harboring a normal microlora, therefore forming an
