. The Dental cosmos. then invested, pins down, in sand andplaster, and soldered with 18-karat goldsolder, or, if German silver pins areemployed, with silver solder, enoughsolder being flowed into the matrix toform a bar of substantial strength andthickness. In case silver solder and German sil-ver pins are used, the finished retainermust be well gilded previous to use. Itis desirable to gild in a proper electricgilding bath, but if one is not at hand,a makeshift may serve. It will be suffi-cient to boil in a porcelain dish in dilutesulfuric acid, adding a few drops ofgold chlorid solution. Thi
. The Dental cosmos. then invested, pins down, in sand andplaster, and soldered with 18-karat goldsolder, or, if German silver pins areemployed, with silver solder, enoughsolder being flowed into the matrix toform a bar of substantial strength andthickness. In case silver solder and German sil-ver pins are used, the finished retainermust be well gilded previous to use. Itis desirable to gild in a proper electricgilding bath, but if one is not at hand,a makeshift may serve. It will be suffi-cient to boil in a porcelain dish in dilutesulfuric acid, adding a few drops ofgold chlorid solution. This is usuallyobtainable ready prepared from drug-gists and photographic dealers. Whenthe gold is seen to be all deposited andthe bath clears, the retainer is taken outand brushed. It is boiled again with alittle more gold solution, and will thenbe sufficientlv gilded to protect the rub-ber against the disintegrating action ofthe silver. After soldering, the retainer is triedto place. It will be found sometimes Fig. up and previous to flasking. When theflask is opened, they are temporarily re-moved through the base of the precaution causes the perforationsto extend a little way beyond the teethinto the plaster, so that posts of fulllength can be used which allow the sur- too massive and it will not be possibleto close the flask without the applianceimpinging on some part of the model,and it is necessary to grind away a littleof the metal until it clears the model. At other times there is difficulty ingetting the pins to enter the tubes of the ELPHINSTOXE, .—TUBELESS TEETH IX PROSTHETIC WORK. 425 teeth. In such cases the teeth causingthe difficulty may be loosened from theinvestment, till the pins can be intro-duced, and when the retainer is againpushed to place, it is generally foundthat the difficulty has been overcome, theteeth readily finding their places again. Sometimes it may be expedient togrind one of the pins a little, at othertimes to enlarge the orific
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Keywords: ., bookcentury1900, bookdecade1910, bookiddent, booksubjectdentistry
