CHAP. XVIII. Of the generation and vse of the Teeth.
COncerning the generation of the Teeth, there are diuers opinions; some thinke they are generated within the Wombe, as Columbus and Eustachius; some without the wombe, as Aristotle; some partly within and partly with∣out, as Hippocrates who maketh a threefolde time of their generation, in his Booke de Carnibus, of a threefolde Aliment which ministreth matter vnto them. The first is from the sustenance they receiue in the womb; the second is after birth by the Milke which the child sucketh; the third is after he hath cast his teeth by the meat * 1.1 and drinke that he eateth whereby new teeth are engendred: for, saith he, whatsoeuer is glutinous in the Aliment that maketh the Teeth, but the fatty part, which heere is more plentifull then in the matter of the rest of the bones, is exiccated by the power of the heate. So also, saith Laurentius, as this threefold kinde of Aliment differs in thicknesse, so doth the solidity, hardnesse and thicknesse of the teeth varye, for those teeth that are engendred of the Aliment which the infant vseth in the wombe, or when hee suckes his mothers brest are but soft and do easily fall away, but those that are made of more solide meats are also firmer.
The truth is that they are generated in the womb together with the rest of the bones, with which they are not delineated but formed and absolued by degrees: wherefore they * 1.2 lye for some time imperfect in the Iawes, neyther do they all breake their prisons at the same time, but some sooner, some later, according as the necessity of Nature dooth re∣quire. And this is the cause why some made a double time of their generation, one in the wombe, another out of the wombe.
In the wombe after the generation of the Iawes there are twelue Teeth formed, foure of which are Shearers, two dog-teeth and six Grinders, all which do want roots and lie hid in their sockets, on euery side compassed therwith, and the gummes whole aboue them. And this may be seene in the raw of an abortiue infant or other creature, yea if it dye pre∣sently after the birth; for if you cut vp the Iaw you shall finde Teeth therein. Some haue bene borne with their Teeth out of their gummes, as of olde time M. Curtius Dentatus, and Cn. Papyrius Carbo. Of later times, the same is reported of Richard Crooke-backe the Vsurper.
The substance of the Teeth being yet imperfect is partly mucous and partly bony, for if you take away the husk of the Tooth, (for there is about euery Tooth such a white, mu∣cous and slimy substance somewhat membranous wherewith the tooth is couered, which * 1.3 also is so much the more mucous by how much the tooth is the softer and the younger) perforating it in the vpper part, that the end of the Tooth may peepe out, then shall you perceiue that the tooth is partly bony, partly mucous; for that part which was to rise a∣boue the gummes is fashioned into a white scale, thin and excauated or hollowed like a * 1.4 Hony-combe, and so the vpper part of the Tooth is bony, hard and hollow. The other part which should haue remained in fixed in the Iaw, is soft, moyst and mucous, like the * 1.5 substance that is in a young quill.
This substance seemeth to haue fibres and threds and to be couered as it were with a thin coate, for the superficies thereof is like to a smooth tunicle fastned and conioyned to the substaunce that it containeth: wherefore a resemblance of the generation of the teeth wee haue some what expressely in the generation of a quill: for the part which is without the skin is horny and hard, but that which is within the wing is softer and moy∣ster, yea sometimes like blood or congealed Phlegme. This soft part of the teeth as they breake the flesh hardneth by degrees, and by degrees becommeth bony. Sometime also it is hollowed within and formed into roots.