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DENTISTRY 



the tooth substance. With these, the hollow in 

 the tooth is scooped out and thoroughly cleaned. 

 If pain be occasioned by this process, the obtund- 

 ing of the tooth's sensitiveness, or ' destroying the 

 nerve,' as it is called, had better at once be resorted 

 to. This is performed in several ways. Where 

 the tooth is single-fanged, as in front-teeth, the 

 nerve, or more correctly the pulp, may be removed 

 by passing a slender broach, or square and pointed 

 brad-shaped, or slender serrated steel probe up 

 into the central cavity of the tooth, with a slight 

 rotary motion, so as to break up and remove the 

 pulp. Where this cannot be done at once the best 

 plan is to destroy the pulp by some caustic applica- 

 tion, such as arsenious acid, chloride of zinc, car- 

 bolic acid, &c., carefully applied, a variety of other 

 substances being used for the same purpose. 



The cavity being properly shaped and cleaned 

 out until its walls are of sound and hard tooth- 

 bone, is to be well dried, and the plug of stopping- 

 material inserted. Various substances are em- 

 ployed for this purpose, and the mode of using each 

 is somewhat different. For temporary stoppings, 

 pure gutta-percha is a serviceable material. A 

 quantity sufficient to fill the cavity, and somewhat 

 more, is to be gently warmed over a spirit-lamp 

 not in hot water and when quite plastic is to be 

 firmly pressed with a blunt-pointed stopping-instru- 

 ment or ' plugger ' into all the interstices of the 

 hollow in the tooth more and more being pressed 

 in, until the surface of the plug so formed is on 

 a level with the surface of the tooth, when all 

 superfluous portions should be removed, and the 

 solid plug smoothly finished. Osteo-plastic fillings 

 consist of varieties of the metallic oxychlorides and 

 phosphates. They are inserted in a soft condition 

 into the tooth, where they harden in the course of a 

 few minutes. 



Another variety of stopping-material consists of 

 amalgams of different kinds. Many absurd state- 

 ments have been made regarding the evil effects of 

 amalgam stoppings, but the only real disadvantage 

 attending their use is shrinkage, and that many of 

 them get black in the mouth, and discolour the 

 tooth, while some that do not get black are friable, 

 and crumble away in a short space of time. Some 

 of those containing copper exercise a beneficial 

 action on the tooth- bone, but darken its colour 

 very much. The amalgam is rubbed up with mer- 

 cury to a firm, plastic consistence, and carefully 

 introduced into the dried cavity in the same way 

 as the gutta-percha plug. 



Gold-stopping is an operation of a much more 

 complicated and difficult description. The materials 

 used here are either gold-foil that is, thick gold- 

 leaf or the peculiar form in which gold exists 

 known as sponge-gold ; or again, 'pellets' of gold 

 made up in a soft spongy condition of various sizes 

 ready for use. In stopping a tooth with gold, even 

 more care is necessary in preparing the cavity than 

 what has been already inculcated. Its shape and 

 condition must now be particularly taken into 

 account, and the nearer it approaches to a cylin- 

 drical form the better. Various modes of pack- 

 ing the gold are adopted according to two con- 

 ditions in which gold exists namely adhesive, 

 where each portion can be welded to the other ; 

 or non-adhesive, where they are securely fixed 

 merely by tightly wedging them together. Non- 

 adhesive gold can be made adhesive by heat- 

 ing it to redness. The surface of a gold plug, 

 formed in any of these ways, should be well con- 

 solidated by hard pressure with a blunt plugger, 

 or lightly hammered with a suitable mallet, and 

 the superfluous portion being removed, it ought to 

 be burnished until it assumes a brilliant metallic 

 lustre. 



Remedies. Many remedies, more or less service- 



able, are in use for what is termed toothache 

 a disorder which, however, is not always one 

 and the same in its nature. Their intention, 

 in general, is either to destroy the nervous fibres 

 existing in a tooth, or to narcotise and render them 

 insensible. Among those acting in the former 

 manner are such as creasote, arsenious acid, carbolic 

 acid, pepsine, chloride of zinc, nitrate of silver, 

 alum, tannin, &c. ; among those acting in the 

 latter mode are chloroform, laudanum, ether, spirit 

 of camphor, menthol, cocaine, &c. In all cases the 

 decayed cavity should previously be well cleaned 

 out, otherwise the remedy employed may be alto- 

 gether prevented from reaching the spot where it 

 is intended to act. 



Extraction. This is the principal surgical opera- 

 tion falling to the dentist. It is performed by 

 means of instruments adapted to the special 

 peculiarities of the tooth requiring removal, or 

 to the circumstances in which it exists. The 

 great matter is, that each tooth should be ex- 

 tracted in accordance with its anatomical configu- 

 ration ; and to accomplish this of course requires 

 an intimate knowledge of the natural form proper 

 to each of these organs individually ; without this, 

 it is impossible to extract any tooth upon a correct 

 principle. The tooth is grasped, as far as the 

 instrument can be made to do so, by that portion 

 of the root or fang which just emerges from, or 

 perhaps which is just within, the socket ; it is 

 then loosened, not exactly by pulling, but rather 

 by moving it in a lateral or in a rotatory manner, 

 in strict accordance with the respective character 

 of fang possessed ; and finally, on its being thus 

 detached from its connection with the jaw, it is, 

 with very little force, easily lifted from its socket. 



Anaesthetics are employed in the extraction of 

 teeth in the same manner as for other surgical 

 operations, where it is desirable to abolish pain. 

 See ANESTHESIA. Neither ether nor chloroform 

 should be given by inexperienced hands, nor should 

 both the giving of the anaesthetic and the extraction 

 be attempted by one individual on any occasion. 

 Nitrous oxide or laughing-gas is of much service, 

 answering all the purposes of chloroform or ether 

 in short operations. A combination of two or 

 more of these anaesthetics has been employed with 

 apparent success, such as nitrous oxide with ether. 

 Freezing the gum, the injection into it of cocaine, 

 and other modes of inducing insensibility, local or 

 general, have been proposed from time to time, but 

 one after another has been abandoned as unservice- 

 able. 



(2) Mechanical Dentistry. The various con- 

 ditions of the mouth requiring the adaptation 

 of .artificial teeth, range from cases where only 

 one tooth may be wanting, to those where not a 

 single tooth remains in the jaw, above or below. 

 Accordingly, artificial teeth are spoken of as partial 

 or complete sets a partial set being one for either 

 upper or lower jaw, where some of the natural 

 teeth still remain ; a complete set being one for 

 either jaw, where none are left, or for both jaws, 

 when both are in such circumstances. 



The transplantation of the teeth of another in- 

 dividual is a very old usage revived every now 

 and again, and equally often falling into desuetude ; 

 and implantation is a recent modification of the 

 process. 



The simplest form of partial sets is what is 

 termed a pivoted tooth. This is an artificial tooth 

 fixed in the mouth upon the fang or root of one 

 whose crown has been lost by decay or otherwise. 

 The most usual mode of procedure is as follows : 

 An artificial tooth, as near as possible to the colour 

 and form of that to be replaced, is selected. This 

 artificial tooth used to be the crown of a natural 

 human tooth corresponding, to that lost, but is 



