TEKTH. 



iiig'thc left eye-looth, lie once curr«l an ulcer, wliich had 

 cxiftt d half a year on the left edge of the tongue. P. Jo. 



3. The converging obliquity is when the crowns of the 

 teeth converge in tht ir fituation, or even crofs each other. 



4. The diverging obliquity is when they diverge. 



5. The lateral obli<iuity is when the fide of tne body of 

 tlie tooth is turned more or lefs forwards or backwards. 



6. Obliquity of the fang. Sometimes the fanrs of the 

 teeth are curved fo obliquely backwards or forwards, that 

 the bottom of the fockets either projefts like a fmall ex- 

 oftofis, or is completely perforated. 



Of the Reduc'ion of an oblique Tooth. — With refpedt to one 

 of the permanent teeth, which is rendered oblique by the 

 prefence of one of the firft fet, the treatment confifts in im- 

 mediately txtraifting the latter. 



The milk-tooth may be known by its pearl colour, its 

 more polilhed furface, and its fmaller fize. The permanent 

 tooth is longer, whiter, ftronger, and of greater breadth. 

 The crowns only of the fecond fet of grinders are fliorter 

 than thofe of the milk-fet. Albini, Annot. Acad. 1. ii. 

 p. 19. 



But an oblique permanent tooth may be replaced in its 

 right poCtion, by the following means. 



1. When the child is very young, and the tooth quite 

 recent, it may be reduced into its proper fituation, by fre- 

 quently prefling upon it with the finger in the courfe of the 

 day. 



2. Or the reduction may be efFefted with a double filk- 

 thread,- fmcared with wax and maftich. A noofe is to be 

 made at each end of the thread, and fattened to the adjacent 

 teeth. The thread, being then divided into two, is to be 

 made to crofs two or three times firmly over the oblique 

 tooth. 



3. By a metallic plate. The length of the plate fhould 

 exceed the meafure of the two neighbouring teeth, together 

 with the oblique one. Its width fliould be lefs than the 

 height of the teeth. It is to be applied to the infide of 

 fuch teeth as incline inwards, and to the ontfides of thofe 

 which inchne outvirards. At the ends of the plate are two 

 holes, through which the filk-threads, fmeared with wax, 

 are to be patted, and, after erofiing each other, are to be 

 tied over the oblique tooth. 



4. By Bruner's machine. When the tooth does not ad- 

 mit of reduftion by the preceding means, Bruner's machine 

 jnay be tried. See A Bruneri Einleitung zur Wiffenfchaft 

 fines Zalii.arztes, p. 83. 



When feveral of the teeth are oblique, the cure is to be 

 attempted by the fame operations ; but when the fide of a 

 tooth inclines forw;ird, it is neceflary to ufe the forceps to 

 bring the part into its right pofition. 



Loofenefs of the Teeth. — Sometimes the teeth become loofe 

 and moveable in their fockets. The proximate caufe of this 

 affeftion may depend upon the lofs of the elafticity of tlie 

 alveoli and gums, upon the too great or too fmall fize of 

 the fockets, or upon the abforption or wafting of t he fwigs. 

 Loofe teeth are very inconvenient in maftication, and eafily 

 drop out. 



Of this complaint there are feveral fpecies, the differences 

 of which are referrible to the caufes. 



1. Loofenefs of the teeth from fecond dentition. After 

 the feventh year, the twenty milk-teeth begin to grow 

 loofe, and fall out, nearly in the fame order in which they 

 were cut. 



2. Loofenefs of the teeth from age. In old perfons the 

 fockets become contrafted, and the canal in the fangs being 

 obliterated, thefe parts alfo diminifh. Hence we fee the 

 reafon why tlic teeth frequently become loofe in fubjeCls ad- 

 vanced in life. 



3. Loofcwfs of the tftth from violent eonculTion*. A 

 forcible conculTion, fuch as happens in f.Jl6 againfl the foelh, 

 diimnilhes the elafticity of the gums and fockets, and of 

 courfe may be a caufe of the prefent difyrder. 



The cure requires corroborant waflies : the tinftura lacca-, 

 aftringent decoftious, red wine, fpirit of wine, ur the terra 

 catechu or fangnis draconis, dilfolved in camjihor.ited fpirit. 



4. Loolenefs of the teeth from relaxation of the gums. 

 There are people whofe gums are pale and relaxed, at the 

 fame time that there is no appearance of fcurvy. 



Here the cure is to be aceomplifhed by the means recom- 

 mended for the preceding cafe. 



5. Loofenefs of the teeth either from caries of the focket 

 or fang. This cafe may be known by the cmifTion of pus 

 from the focket of the loofe tooth. Sometimes a cure may 

 be effefted by gargles ; but, in general, if the tooth is alfo 

 painful, it ought to be extrafted. 



6. Loofenefs of the teeth from fcnrvy of the gums. In 

 fubjefts with fcurvy, the gums become loofe and fungous, 

 and the fockets filled with a fetid purulent matter : hence 

 the teeth are loofencd. 



The cure requires the internal exhibition of antifcorbutic 

 medicines, and the ufe of antifcorbutic wallics. 



7. Loofenefs of the teeth fruin mercury. Mercury z&.i 

 fpecifically upon the gums, dellroying their tone, and pro- 

 moting the fecretion of faliva. Hence, perfons ufing mer- 

 cury, either outwardly or inwardly, arc liable to have their 

 teeth rendered loofe. 



The cure demands purgative medicines, the expulfion of 

 the mercury from the fyftem, and the ufe of tonic gargles. 



Defeat oj Teeth. — When the teeth are entirely wanting, 

 feveral very uiijileafant efietts are neceflarily the conh;- 

 quence. The proper maftication of the food being then 

 abfolntely iinpofilble, cardialgia, and other complaints con- 

 nected with dilhcult digeftion, ai'e produced. The de- 

 ficiency of the grinding teeth occafions a collapfe of the 

 cheeks, and of courfe an nnfightly emaciation of the coun- 

 tenance ;. while the want of the incifores fpoils the voice. 



1. It is natural for all young infants to be without teeth, 

 until they are fevcn or eight months old ; but when the 

 teeth do not begin to come through the gums after a child 

 is a twelvemonth old, tlien the backwardnefs of dentition 

 may be confidered as morbid. 



2. In old perfons, the teeth naturally fall out, and the 

 alveoli contraft into a kind of ftiarp edge, covered with the 

 callous membrane of the gums, by which the fofter fpecies 

 of food may yet be chev.vd. 



3. Want of teeth from rickets. When the rudiments of 

 the permanent teeth are deftroyed with the milk-teeth, then 

 of courfe no fecondary teeth ever make their appearance. 



4. Lofs of teeth from violent caufes. Under this head 

 we comprehend the defett of one or feveral teeth, drawn, 

 or beaten out. 



5. Lofs of teeth from necrofis. Every form of this dif- 

 order makes the teeth fall out in little pieces. 



6. Lofs of teeth from fcurvy. In fituations where the 

 fcurvy is prevalent, it is common to meet with numerous 

 perfons who have loft their teeth in the very prime of life. 



Every kind of deficiency of teeth, except that which be- 

 longs to infancy, cannot be remedied in any other way but 

 by the infertion either of artificial or natural teeth. 



Of the Infertion of Teeth There are various fpecies of 



this operation, but all of which may be included under the 

 following heads. 



1. The infertion of a healthy proper tooth. When a 

 tooth that has been cxtraAed, or beaten o\it, appears to be 

 entirely found, it is to be immediately replaced in the focket, 

 and tied with thread to the adjacent teeth. Sometimes it 



fpon- 



