![]() The significant decrease in the rigidity of spot-bonded FRC splints if compared with full-bonded retainers suggests further tests in order to propose this technique for clinical use, as they allow physiologic tooth movement, thus presumably reducing the risk of ankylosis.įiber-reinforced composite (FRC) retainers are an aesthetic alternative to conventional Stainless Steel splints. The highest loads were reported for full bonded FRCs. At the maximum load, no significant differences were reported among spot- and full-bonded metallic splints and spot-bonded FRCs. Higher force levels were reported for full-bonded metallic flat and round splints and the highest loads were recorded for full-bonded FRCs. Both at 0.2 and 0.3 mm deflections, the lowest load required to bend the retainer was recorded for spot-bonded stainless steel flat and round wires and for spot-bonded FRCs, and no significant differences were identified among them. Stainless steel rectangular flat, stainless steel round, and FRC retainers were tested at 0.2 and 0.3 mm deflections and at a maximum load. The purpose of the present investigation was to evaluate bending and fracture loads of FRC splints bonded with conventional full-coverage of the FRC with a composite compared with an experimental bonding technique with a partial (spot-) resin composite cover. Therefore they can conduct as their ions are free to move.Fiber reinforced Composite (FRC) retainers have been introduced as an aesthetic alternative to conventional metallic splints, but present high rigidity. Ionic compounds dissolve in water easily, when they do this their lattice breaks up completely and water molecules surround the seperated ions. ![]() A cube of tightly packed alternate metal and non-metal ions. ![]() This is a regular repeating arrangement of metal and non-metal ions which creates compounds with very high melting points which conduct when molten or in solution but never when solid. ![]() Ionic compounds form what is known as a lattice structure. When these two charged particles come together they form an ionic bond because the positive magnesium ion is attracted to the negatively charged chloride ion. To become stable it must gain an electron to obtain a full outer energy level. Non-metals form negative ions because they gain electrons to become stable.Ĭhlorine (Cl) has an electron arrangement 2,8,7. They change into ions with a two positive charge. To become stable it must lose its two outer electrons to obtain a full outer energy level.Ītoms are neutral because they have equal numbers of protons and electrons however, when they lose two electrons they are no longer neutral. Magnesium (Mg) has the electron arrangement 2,8,2. Metals form positive ions because they lose electrons to become stable. The ionic bond is the electrostatic force of attraction between a positively charged metal ion and a negatively charged non-metal ion. Ionic bonds are formed between a metal and non-metal, for example sodium chloride.Īn atom of sodium will lose an electron and form a positive ion.Īn atom of chlorine will gain an electron and form a negative ion. Learn about the basic structure of an ion, related to atomic number and mass.
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