Dental cosmos . of protecting cushion, or to preserve an open space forthe tooth to grow into. In my opinion the view first announced byHertz in 1866, that the enamel-organ is stored-up material for thebenefit of the growing enamel itself, is the correct one, the sameas is the intermediate layer. The reasons for this are given byHeitzmann and Bodecker in their above-quoted article. One fact will strike every observer, viz., that the enamel is seldom, GROWTH OF ENAMEL. 761 if ever, perfectly symmetrical in the growing tooth, one side beingbroader, to the extent of five or six times, than the ot
Dental cosmos . of protecting cushion, or to preserve an open space forthe tooth to grow into. In my opinion the view first announced byHertz in 1866, that the enamel-organ is stored-up material for thebenefit of the growing enamel itself, is the correct one, the sameas is the intermediate layer. The reasons for this are given byHeitzmann and Bodecker in their above-quoted article. One fact will strike every observer, viz., that the enamel is seldom, GROWTH OF ENAMEL. 761 if ever, perfectly symmetrical in the growing tooth, one side beingbroader, to the extent of five or six times, than the other ; some-times it is found only on one side of the developing tooth, while onthe other nothing but delicate fibrous connective tissue is these facts we must conclude that the myxomatous form ofthis organ is by no means a characteristic or an absolute require-ment. How can we. explain the scantiness of this organ at the summit ofthe crown, where in full development the enamel has the greatest Fig. Developing tooti of sheeps fachts, 10 centimeters long —D, dentine in longitudinal and , row of ameloblasts at rest. A1, ameloblasts broken up into medullary tissue, preceding the forma-tion of enamel. I, I, intermediate layer. M, M, myxomatous enamel-organ. C, capillary blood-vessels. X 100J. diameter ? Can the original enamel-organ, even ever so broad, sufficefor the production of the whole enamel ? Is not the enamel coat ofa temporary tooth five, nay, ten times as broad, as the originalenamel-organ? All this strongly points toward the fact that thebudding external epithelium, and even the primary epithelial peg,must furnish material for the building of enamel, no matter whatthe intermediate or subsequent changes of this tissue-may be. In conclusion, I wish to say that I have studied the developmentof enamel in pigs and sheep, and have found the relations similar tothose in human beings. (See Fig. 5.) In the sheeps foetus, ten centi- 762 THE DENT
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