A practical treatise on mechanical dentistry . to the toe of the horseshoe. Thebar extending between the two roots is the truss of the , place the appliance on the cast (Fig. 573), holding it in 6o6 MECHANICAL DENTISTRY, position with wax, and select the teeth to take the place of themissing bicuspids and molar. The best form for this purpose isa tooth having holes extending through it vertically from theneck to the grinding surface, similar to the well-known Bonwillcrown. The crowns used should be large enough to fill the space rathertightly, even if their sides have to be flattene
A practical treatise on mechanical dentistry . to the toe of the horseshoe. Thebar extending between the two roots is the truss of the , place the appliance on the cast (Fig. 573), holding it in 6o6 MECHANICAL DENTISTRY, position with wax, and select the teeth to take the place of themissing bicuspids and molar. The best form for this purpose isa tooth having holes extending through it vertically from theneck to the grinding surface, similar to the well-known Bonwillcrown. The crowns used should be large enough to fill the space rathertightly, even if their sides have to be flattened to let them in. Ifthe teeth do not fill the space perfectly, a small portion of plasticfilling material crowded between them, as mortar between thegranite blocks in the arch of a railway bridge, will greatly increasethe strength of the work. After the teeth are ground to fit, and the proper length forocclusion ascertained, the truss is covered with a film of wax, uponwhich the crowns are again pressed to their positions. Upon the Fig. removal of the crowns the impression of the holes running throughthem will be found in the wax. At these points drill holes throughthe bar with a small twist drill run by the dental engine, and intothese fit and solder the pins for the support of the crowns, as shownin Fig. 574. The bridge is now ready to be attached permanently. Set thecrowns in position upon their supporting pins, to secure the properalignment. (If the operation were upon the upper jaw they wouldhave to be held with wax.) Put into the canals of the supportingroots (the cuspid and first molar) a sufficient quantity of somequick setting plastic, as oxyphosphate, to about half fill the pulpchamber, but not enough to prevent the supports of the trussfrom being forced home. Force the bridge supports to place, andafter allowing the filling material to become set remove the crowns. BRIDGE DENTURES. 607 Fill the remainder of the pulp chamber and the whole of thecollar with gold,
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectdentist, bookyear1903
