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- MULTI-TYPE ELECTROWELDED IMPLANTS |
term is used to describe an implantological technique that complies with modern
trends of surgery which is gradually becoming less invasive every day. This means
less suffering for the patient who also has the advantage of immediate functional
adjective "multi-type" refers to the fact that the operator can choose
from a wide range of implants with different shapes, lengths and calibre.
This enables the structure of the implant to be adapted to the patient's anatomical
characteristics. It does not require preparatory surgery which sometimes involves
bone grafting techniques from other anatomical districts.
atraumatic nature of multi-type electrowelded implantology makes it the preferred
technique of first choice, reserving more invasive techniques as second choice
- only to be used in the event of failure.
Depending on the characteristics
of the specific type of implant used, its immediate or long-term failure will
result in small lesions to the bone apparatus, but following spontaneous repair
it can be re-utilised after a short interval.
the implants together also leads to a different mode of distributing the stresses
acting on the structure which no longer acts as individual implants and instead
participates in a joint effort providing mechanical support for the prosthesis.
The most immediate concept when attempting to imitate the function of an
organ is to imitate its form and structure. In practice, however, this is not
Therefore, when attempting to reproduce the tooth it is natural
to use the concept of tooth - monoimplant.
But how would an engineer attempt
to make up for the lack of gomphosis?
This is a system that perfectly absorbs
the functional stress in completely healthy conditions.
This mechanism is
absolutely necessary not only as a means of discharging stress, but also to compensate
for geometric and structural alterations undergone by the jawbone. All this constitutes
a mechanical system comprising the "prosthesis implant structure - bone".
The three units are all subject to occlusal stress and each reacts in its own
However, the individual reactions must interact with one another.
The prosthesis must comply with:
Law = the overall radicular surface of the posts must be equal or greater than
the presumed surface of the replaced teeth.
flexion and curve of the beam are proportional to the cube of its length and inversely
proportional to the cube of its thickness. A bridge beam is subject to bending
stress whatever its length. The thrusts transmitted by the intermediate elements
to the dental posts differ in intensity and direction from those imposed by single
reconstructions. The transfer stresses exerted on a means of anchorage have a
medio-distal direction, whereas they are vestibular-lingual on an isolated element.
Even the discharge of the stress vectors without apparent movement provokes
the same effects leading to the perimplant conoid degeneration of monoimplants.
Bone regeneration surgery is itself confirmation of the inadequacy of this method.
This technique is not required when electrowelded structures are used
B) The mandibular bone can be thought of as a box-type girder with a perimetral
structure reinforced by thickening (Mylohyoid lines) and containing cancellous
bone reminiscent of a honeycomb structure.
complex is not rigid but is subject to elastic deformations that are discharged
on the implant, which cannot absorb them because it lacks any natural suspension
in the form of gomphosis.
given that no prosthetic artefact can transmit the stress to the bone structure
in an absolutely axial manner, and given that the monoimplant structure lacks
any physiological absorption, a discrepancy is created between the flexion of
the bone and the rigidity of the implant. On the contrary, in dentures mounted
on electrowelded implants the implant complex acquires an adaptability that, like
reinforced concrete structures, can follow the flexibility of the underlying bone.
This occurs without disturbing the balance of the transition section at the cortical
level (the latter's conoid collapse has never been reported). Owing to its construction
method, resting on a monobloc structure in which there is practically no interimplant
diastema (namely the distance is so small it can be said to be zero), the prosthesis
discharges the stresses without bending.
It is the deep implant structure
that follows the bone modulus of elasticity.
intraoral welding process is completely innocuous and, based on research by Prof.
Mondani, it is performed using a microwelder that acts on the titanium structures
using a process of crystal compenetration without the need for other metal. This
process is known as syncrystallisation.
studies which are now being expanded, carried out at the Department of Biomechanics
at Turin Politecnico, highlight the maximum concentration of tensions at the emerging
neck of the implant. This fact is confirmed by the clinical observation of the
cone of cervical resorption in all unwelded implants, including both the so-called
"osteointegrated" and "traditional" models.
clinical syndrome is not found around electrowelded structures, confirming the
hypothesis of a better distribution of stress. These techniques can therefore
be used to bypass anatomic districts that would otherwise contraindicate the use
of dentures on implants.
This makes it possible to treat both mandibles with
severe resorption and upper jawbones with highly developed sinuses.
of metal-ceramic dentures allows optimal cosmetic results to be achieved together
with maximum respect for the periodontal structure. It is not necessary to use
resins or other materials to achieve the isodromic adaptation of the prosthetic
would like to express my warmest thanks to my friend and colleague Marco Pirovano,
witness to a glorious past and artificer of scientific progress.|