levre superieure, dans un deuxieme temps operatoire. Rev. odontol., Par., 1896, xxxi, 72-80.—Bingham (Stillman R.) [1829-96.] (Obituary.) Dental Cosmos, Phila., 1896, xxxviii, 260-263, portr. -Also: Dental Rev., Chicago, 1896, x, 161. Also: West. Dent. J., Kansas City, 1896, x, 49, portr.—British DentalAssociation. Fifth report . . . as to the condition of the teeth of school children. J. Brit. Dent. Ass., Lond., 1896, xvii, 75-78.— Bur-chard (H. M.) The origin of salivary calculus. Am. J. Dent. Sc, 1896, xxix, 497-508.—Buxton (D.) The nature of anaesthesia. Dental Rec, Lond., 1896, xvi, 67-74.—Carmichael (J. P.) Crown and bridge work. Dental Rev., Chicago, 1896, x, 103-106.—Cunningham (G.) The advantages of a systematic training in mechanical dentistry. Ibid: 106-112. [Discussion], 122-124.—Daboll (G. C.) The mission of the matrix. Dental Rev., Chicago, 1896, x, 100-103. [Discussion], 117-122.—Damain. Le cin6matographe. Rev. odontol., Par., 1896, xxxi, 66-72.— Darby (G. D. B.) Is uric acid an important factor in dental disease? Internal Dent. J., Phila., 1896, xvii, 143-151. [Discussion], 180-189.—De Marsi (A.) Contributo alio studio delle cisti della mascella inferiore. Bull. d. Soc. med. di Bologna, 1895, 7. s., vi, 518-525.—Dwinelle (William Henry.) [1819-96.] (Obituary.) Dental Reg., Cincink, 1896, 1, 154. Also: Dental Rev., Chicago, 1896, x, 238.—Ellis (J.) Shun bolted flour: why Americans lose their teeth at an early age. Dental Reg., Cincin., 1896, 1, 124-126.—Farrar (J. N.) Anchorage. West. Dent. J., Kansas City. 1896, x, 126-128. Correction of a double difficult case of irregularities of the teeth at thirty years of age. Ohio Dent. J., Toledo, 1896, xvi, 57; 118.— Farlow (J. W.) Some remarks on removal of the tonsils. Tr. Am. Laryngol. Ass., 1895, N- Y> r896, xvii, 60-64.— Flagg* (J. F.) Preparation of pulp-cavity and canals. Dental Cosmos, Phila., 1896, xxxviii, 199-204.—Fox (Charles James.) [1833-96.] (Obituary.) Dental Rev., Chicago. 1896, x, 162.—Friedemann. Ueber die Topographie der Cavitaten und ihre Anwendung in einem neuen zahnarztlichen Krankenbuche. Deutsche Monatschr. f. Zahnh., Leipz., 1896, xiv, 105-124.—Gebiihren fur approbate Zahnarzte. Deutsche med. Wchnschr., 1896, xxii, No. 10, Sonderbeil., 4.—Geronzi (G.) Su di un caso di emiatrofia linguale. •Bull. Soc. Lancisiana d. osp. di Roma, 1895, xiv, fasc. i, 36-45.—Globensky (S.) A few notes on dental prosthetics. Am. J. Dent. Sc, Bait., 1896, xxix, 508-511.—Godon (C.) La fin d'une transplantation. Odontologie, Par., 1896, 2. s., iii, 103-105. Note sur la retractility de l'amalgame et rimperm6abilite des obturations. Ibid: 6-9.—Graham (G. W.) A tooth growing in the nose. Charlotte [N. C] M. J., 1896, viii, 155.—Gregson (George.) Dent. Ass., Lond., 1896, xvii, 122.— Hamilton (T. K.) Case of xerostomia. Australas. M. Gaz., Sydney, 1895, xiv, 480-482.—Hatty asy (L.) [Effect of caustic potash and hydrochloric acid in the treatment of gangrene of the rootcanal.] Orvosi hetil., Budapest, 1896, xl, 86; 102.—Heckler (J. W.) The treatment of teeth and roots preparatory for crowning. Dental Cosmos, Phila., 1896, xxxviii, 205-208.—Henister (J. G.) The destruction of children's teeth; cause and prevention. J. Am. M. Ass., Chicago, 1896, xxvi, 414.—Hewett (A. C.) Dental amalgams. Dental Rev., Chicago, 1896, x, 176-188. [Discussion], 202-214.—Hofmeister (F.) Zur Schleich'schen Infiltrations-Anasthesie. Beitr. z, klin. Chir., Tubingen, 1895-6, xv, 563575— Jack (L.) Plantation of teeth. Dental Cosmos, Phila., 1896, xxxviii, 185-193. [Discussion], 243-245. Also; Internat. Dent. J., Phila., 1896, xvii, 133-143. [Discussion], 171-175.— Jean (F.) Nouveaux appareils de redressement. Odontologie, Par., 1896, 2. s., iii, 9-13.—Jenkins (C. W.) The president's address. [American Dental Society of Europe.] Dental Rev., Chicago, 1896, x, 88-94.—Jones (J- H.) Treatment of deciduous teeth. Brit. J. Dent. Sc, Lond., 1896, xxxix, 193-202. [Discussion], 231-233.—Joseph (M.) De la gangrene nevropathique de la pulpe dentaire. Odontologie, Par., 1896, 2. s.f iii, 65-80.— Kells (Charles K.),sr. [182796.] (Obituary.) Dental Cosmos, Phila., 1896, xxxviii, 264.—Knight (C. H.) Cyst of the maxillary sinus. Tr. Am. Laryngol. Ass., 1895, N. Y., 1896, xvii, 159-163. —Landgraf. Zur Pathologie des weichen Gaumens. Berl. klin. Wchnschr., 1896, xxxiii, 202-204.—kej merle. Etude sur la density des aurifij cations d'apres les diflf&rents modes I op6ratoires. Odontologie, Par., 1896, 2. I s., iii, 1-6.—Linkenheld. Zur KieferI hohleneiterung. Mtinchen. med. Wchnschr., 1896, xliii, 176.—Loup. Injecteur automatique d'antiseptiques avec chauffeur d'eau et appareil distributeer d'antiseptiques. Odontologie, Par., 1896, 2. s., iii, 89.—McKay (R.) Amalgam. Dental Rec, Lond., 1896, xvi, 57-64.— Magrnan. Retr6cissement pharyngien. J. de m6d. de Bordeaux, 1896, xxvi, 82.— Marthen (G.) Ueber todtliche Chloroform-Nachwirkung. Berl. klin. Wchnschr., 1896, xxxiii, 204-207.— MaWhinney (E.) Systemic medication for dental purposes. Dental Rev., Chicago, 1896, x, 81-88.—Miller (W. D.) The transparent zone in decay of the teeth. Brit. J. Dent. Sc, Lond , 1896, xxxix, 175-183.— Mills (W. A.) Specific treatment of necrosis of the alveoli and maxillae with aromatic sulphuric acid. J. Am. M. Ass., Chicago, 1896, xxvi, 518. —Mingrazsini (G.) Osservazioni cliniche ed anatomiche sull'emiatrofia della lingua. Arch. ital. de otol. [etc.], Torino, 18961 iv, 74-92.—Morton (W. J.) Electric medicamental diffusion, or cataphoresis and its relation to dental surgery. Dental Cosmos, Phila., 1896, xxxviii, 210-232.—New York dental law. J. Am. M. Ass., Chicago, 1896, xxvi, 593.— Palmer (S. B.) Adaptation of fillings to conditions of the teeth, together with electrical disturbances caused by gold, tin and amalgam fillings. Ohio Dent. J., Toledo, 1896, xvi, 128-133. Dental science then and now. Am. J. Dent. Sc, Bait., 1896, xxix, 481497.—Park (R.) Carcinoma of lip and jaw. Med. News, N. Y., 1896, lxviii, 322. —Patterson (J. D.) Medicinal treatment vs. expert manipulation in dental practice. West. Dent. J., Kansas City, 1896, x, 99-101.—Peck (A. H.) The preparation of compound proximal cavities in bicuspids and molars. Dental Rev., Chicago, 1896, x, 75-81.—Poinsot. Action galvanique des appareils metalliques dentaires. Odontologie, Par., 1896, 2. s., iii, 14-16.—Prelswerk (G.) Ein Fall von Neuralgie auf septischer Grundlage. Deutsche Monatschr. f. Zahnh., Leipz., 1896, xiv, 100-102.—Read (T. G.) Presidential address. [Bread and dental caries.] Brit. J. Dent. Sc, Lond., 1896, xxxix, 214-220.—Bhein (M. L.) Alveolar abscess: preventive and curative treatment. Dental Cosmos, Phila., 1896, xxxviii, 193-199. [Discussion], 237-242. —Riesman (D.) Xerostomia (dry mouth), with the report of a case. Phila. Polyclin., 1896, v, 91.—Roach (J.) Common ground of medicine and dentistry. J. Am. M. Ass., Chicago, 1896, xxvi, 412414.—Bobbins (C.) Amalgams in everyday practice. J. Brit. Dent. Ass., Lond., 1896, xvii, 78-85.—Rose (C.) Das Zahnsystem der Wirbeltiere. Anat. Hefte, 2. Abt., Wiesb., 1895, iv, 542^591.—Rollins (W. H.) Dental anaesthesia by cataphoresis. Internat. Dent. J., Phila., 1896, xvii, 151-153.—Ross (F. W. F.) Decayed teeth and puerperal fever. Brit. M. J., Lond., 1896, i, 696.—Roughton (E. W.) Tumours of the mandible. Brit. J. Dent. Sc, Lond., 1896, xxxix, 145-155.—Roussel. Epith61iome de la LIST OF UNITED STATES PATENTS PERTAINING OR APPLICABLE TO DENTISTRY THE langue. Loire m6d., St.-Etienne, 1896, xv, 41.—Roy (M.) De l'allongement des dents depourvues d'antagonistes. Odontologie, Par., 1896, 2. s., iii, 16-20. Note au sujet de deux cas d'eruption tardive. Ibid; 87.—Rymer (J. F.) Rhizodontrophy. J. Brit. Dent. Ass., Lond., 1896, xvii, 87-89.—Spear (J. M.) Antisepsis. Am. J. Dent. Sc, Bait., 1896, xxix, 512-518.—Spring* (W. A.) Tin and gold. Dental Rev., Chicago, 1896, x, 9497. [Discussion], 112-117.—Starck (H.) Tuberculose Halsdriisen im Zusammenhang mit cariosen Zahnen. Miinchen med. Wchnschr., 1896, xliii, 145-147.— Stearns (G. O.) [1815-96.] (Obituary.) Dental Cosmos, Phila., 1896, xxxviii, 264. —Stoos (M.) Zur Aetiologie der Stomatitis aphthosa. Mitth. a. Klin. u. med. Inst. d. Schweiz, Basel u. Leipz., 1895, 3 R., 85-102, 1 pi. Untersuchungen liber den Soor des Mundes. Ibid: 103130, 1 pi.—Thompson (A. H.) The progress of modern methods in dental practice. J. Am. M. Ass., Chicago, 1896, xxvi, 519-521.—Tims (H. W. M.) Notes on the dentition of the dog. Anat. Anz., Jena, 1895-6, xi, 537-546.—Tomes (C. S.) On the chemical composition of enamel. J. Physiol., Lond., 1896, xix, 217-223.— Wardill (G. J.) Death under chloroform at a dentist's rooms. Lancet, Lond., 1856, i, 803.—Webster (G. A.) Some interesting cases. West. Dent. J., Kansas City, 1896, x, 87-90.—West (R. M.) Two cases of gangrenous stomatitis, one ending fatally. Lancet, Lond., 1896, i, 704.—Wilson (G. H.) Artistic staining of artificial teeth. Ohio Dent. J., Toledo, 1896, xvi, 113-117—Wittkowski. Ueber die mangelhafte Beriicksichtigung des Schonheitssinnes in der zahnarztlichen Technik. Deutsche Monatschr. f. Zahnh., Leipz., 1896, xiv, 80-86.—Wright (J.) A cyst of the nasopharynx and a cyst of the oropharynx. Tr. Am. Laryngol. Ass., 1895, N. Y., 1896, xvii, 171-176. —Young- (W. G.) A case of trifacial neuralgia cured by neurectomy. Med. Mirror, St. Louis, 1896, vii, 64-67. Also: West. Dent. J., Kansas City, 1896^ x, 101-105. ISSUED DURING MARCH, 1896. March 10.—No. 556,202, to George W. Nutz. Dental plugger. "17.—No. 556,701, to George B. Snow. Oil-flame regulator for vulcanizers. "" No. 556,702, to George B. Snow. Oil-flame regulator for vulcanizers "24.—No. 556.952, to C. E. Akeley and C. G. Junkermann. Head-rest. "j/.—No. 557,159, to P. R. Skinner. Electrical dental plugger. 11 " No. 557,422, toT. W. Onderdunk. Electrical dental plugger. "" No. 557,523, to A. J. Brown. Dental tool. Dental Cosmos. Vol. XXXVIII. PHILADELPHIA, JUNE, 1896. No. 6. ORIGINAL COMMUNICATIONS. On The Formation And Structure Of Dental Enamel.* BY J. LEON WILLIAMS, D.D.S., L.D.S., F.R.M.S., LONDON, ENG. (The substance of this series of papers was read before the Royal Society of Great Britain on December 12, 1895.) (Concluded from page 296.) On commencing the study of completely formed human enamel under high powers it soon became evident that I had entered an almost unexplored field for investigation. One has only to glance over the recent literature of the subject to see how inadequate, vague, and contradictory are the views held concerning such appearances as are presented in enamel even when seen under low and medium powers of the microscope. The almost complete failure to apprehend the significance of the appearances seen under high powers is largely due, I believe, to the fact that the method of the formation of the tissue has not been clearly seen and comprehended. Dr. R. R. Andrews, in a recent paper which I have previously mentioned, has described at considerable length certain fibrous appearances to be seen in forming enamel. And while there seem to be errors of no great importance in this paper as to the origin of these fibers, I regard his work as a long step in advance of anything which had preceded it. But Dr. Andrews says of this fibrous net-work or substructure, '' When the calcification of the (enamel) rod is complete, the lime-salts have been so densely deposited as to entirely obscure the appearance of any fiber.'' Again he says, "After the enamel is wholly formed, its (the fibrous net- work) existence seems to be wholly blotted out in the dense calcification of the tissue." Tomes also says, "The individual fibers (enamel-rods or prisms) are to all appearance structureless in perfectly formed human enamel, but a faint transverse striation, fainter but otherwise not unlike that * Copyright, 1896, by J. Leon Williams. of voluntary muscle, is so general that it cannot be regarded as pathological, although it is most strongly developed in imperfect brownish enamel.'' Again, "the calcification of the enamel should be so complete that its fibrous* structure is but slightly apparent in longitudinal sections, and the individual fibers should appear structureless with the exception of the feebly marked striation." Sudduth makes no mention of Section Of Enamel From Human Tooth. X 300. Ground under water while still moist and untouched by acids. Mounted in balsam and photographed immediately. The enamel-rods in some places are seen to lie close together and in othtr parts to be separated by cement-substance. The transverse markings of the rods are everywhere distinctly seen. having observed any internal structure in the enamel-rods, and even in those coarser markings, the varicosities, he evidently fails to perceive any direct connection between these markings and the processes of enamel-formation which have produced them. Abbott, in * By fibers Mr. Tomes always means the enamel-rods or prisms, and not the finer fibers which are described in these articles. his recently published work on *' Dental Pathology and Practice,'' gives no hint that he has ever seen the true structure of completely formed normal human enamel. Certainly there is no suspicion of the real structure in the one photograph of enamel which is the only illustration of any value on that subject in the book. Von Ebner claims to have demonstrated the presence of a system of minute canals in enamel, and he believes that the varicosities of the rods is an artificial appearance produced by the action of acids. Bodecker and Fig. 60 Section prepared by Mr. J. Howard Mummery. The transverse markings ot the enamelrods are more pronounced in this specimen than in any I have seen. The enamel-rods are everywhere seen to be united by projecting processes. Abbott claim to have seen organic fibers passing between the enamel-rods and giving of! thorn-like processes. They have also observed the enamel-rods breaking up into nucleated protoplasmic bodies which may or may not become recalcified. Von Ebner regards these opinions as errors which have grown out of observations made upon improperly prepared specimens. Heitzmann and his pupils retort that Professor Von Ebner's work is to be discredited |