摘要 |
Means to decrease the effects of polymerization shrinkage, increase stiffness, decrease the coefficient of thermal expansion and improve the durability of composite restorations by use of inserts are disclosed. Pieces of an aluminoborosilicate glass are phase-separated by heating to 870 DEG C. for 2 hours producing opaque inserts with silica-rich surfaces. Boiling for 1 hour in aqueous 0.5 N NaOH solution removes the surface layer, and produces a rough-textured surface with increased area. The surface texture plus treatment with an organofunctional silane provides for both micromechanical and chemical bonding with composite resins. Cavities in teeth are partially filled with unhardened composite material, and inserts of appropriate size and shape are pressed into the cavity so that the insert constitutes as much as possible of the finished restoration and its surface. The excess extruded composite material is removed with a hand instrument, and the composite containing the insert is light cured. The glass insert, together with the surrounding hardened composite, is contoured with high-speed rotary diamond instruments. Alternative types of inserts are also described.
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