Biomedical Engineering Reference
In-Depth Information
Some examples of brands of commercial materials are:
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RMGICs: Fuji II LC (GC), Riva Light Cure (SDI), Photac-Fil
(3M-Espe) and Ionolux (Voco);
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HVGICs: Fuji IX (GC), Riva Self Cure (SDI), HiFi (Shofu),
Ketac Molar (3M-ESPE), Chemfil Rock (Dentsply) and Ionofil Molar
(Voco).
The main differences between these two types of material relate to
their mechanical properties and implementation. HVGICs have the
advantage of single-step placement (particularly attractive property for
proximal cavities) and, in certain formulations, have accelerated
chemical bonding. However, they are not robust in the medium term
in proximal areas [QVI 10]. Limiting their use proximally for less than
two to three years in the dental arch, and also for their use in small- to
medium-sized cavities, is therefore recommended [FOR 03].
Nevertheless, it is possible that the use of a protective varnish (G-Coat
Plus, GC) may considerably improve durability [FRI 11]. However,
one might question how bioactive fluoride-releasing properties are
maintained when a protective varnish is used.
Finally, it should be noted that a new high-viscosity RMGIC is
now available (HV Riva Light Cure, SDI); this is an RMGIC that can
be used as an HVGIC.
11.3. Dental adhesion and surface treatments
One of the most interesting properties of RMGICs is their ability to
adhere naturally to dental tissues. Their bond is essentially chemical
rather than micromechanical and involves ionic and hydrogen bonds.
These chemical bonds form a tight and durable sealing, protecting and
preventing the pulp risk of secondary caries.
Adhesion to collagen would essentially be by hydrogen and ionic
bonds, with the structure of the apatite of the dentine. Adhesion to the
mineral part would follow:
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a dynamic process of phosphate and calcium ion exchange
between COO
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groups of the polyacrylate and the dentin of
