Quiz compend on irregularities of the teeth

Front matter

COMPEND

M

CUuJuAK

Preface

^T^HE object of this work is not intended " to take the place of the larger and more complete works, but to be used as a primer and reference for advanced students. The quiz compend principle has answered so excellently in medicine as to entail a similar system for dental students.

Etiology has been discussed at length since its knowledge must precede and determine the treatment. Questions and answers generally prove suggestive to the teacher as to new lines of study.

In the treatment of irregularities of the teeth, all forces may be applied individually to a given case. The author has intentionally avoided a discussion of special treatment since every teacher has of necessity his own methods of operation.

Contents

Chapter. Page.

I. History 9

II. Heredity , 29

Chapter I. History

Q. Is practice of dentistry ancient?

A. It was a very early specialty of medicine. According to Sayce and others, the Assyrians early practiced tooth filling with gold, and allied procedures.

Q. What was the folklore belief of dental decay?

A. That it was due to a worm in the tooth.

Q. Did the Assyrians reach a very high level in medicine?

A. They did not reach a higher level in medicine and surgery than that of the Chinese of to-day, who are presumably the inheritors of their science.

Q. What country had attained a relatively high status at this early period?

A. In Egypt nearly every branch of medicine had attained a high standard at the time of Herodotus.

. Q. Do records show that dentistry was practiced earlier than this period?

A. As shown by the Eber's papyrus, dentistry was a differentiated specialty of medicine much earlier.

Q. When was gold used?

A. It was employed by the Egyptians for filling teeth as well as for correction of irregularities.

Q. What evidence is there for this?

A. Mummies are found containing teeth held in place and directed by gold or silver wires or plates.

Q. What other peoples practiced dentistry in early times?

A. In Hindoo civilization, dentistry early reached a high status as a specialty of medicine. Such civilization fell later into decay when the folklore notion of disease due to the worm in the tooth resumed its prominence.

Q. Was Hippocrates particular in regard to dental operations?

A. Caution was advanced by him in extraction of teeth and preserving them.

Q. What other important point was he critical about?

A. He attacked principally the fetichic origin of disease.

Q. What did this notion lead him to?

A. As this played a large part in compelling unnecessary extraction of teeth, he naturally was led to describe the character of teeth and the indication for their extraction.

Q. What important scientist followed him, and what great lesson did he teach?

A. One hundred and sixty years after him Erasistratus deposited in the temple of Apollo at Delphos an odontogogue or leaden tooth forceps, intimating that only teeth should be drawn which were loose enough to be extracted with this instrument.

Q. What was the lesson to teach?

A. This (an ex-voto offering for recovery from disease) was probably intended by Erasistratus as a popular lesson against too early extraction of teeth.

Q. Were the Romans influenced by this?

A. So far as dentistry is concerned, the Romans were as much influenced by Etruscan as by Greek culture, although the last had a very early influence.

Q. Were the Etruscans versed in dentistry?

A. They practiced dental procedures resembling, but more complete even than those of Greece.

Q. Did the Romans early practice dentistry?

A. In Rome artificial dentures, evidently modeled on Etruscan types, were made ere the period of the laws of the 4t Twelve Tables."

O. When did Celsus practice?

A. He practiced A. D. 30. He was considered rather rough in his surgical operations.

Q. When did Galen practice, and what important name did he give to some of the teeth?

A. Galen practiced 150 A. D. He gave the canine teeth the present popular term, eye teeth, because he believed they were supplied by the optic nerve.

Q. What great medical school developed in the seventh century?

A. The Greek, Etruscan, Roman, and Arabian culture met at the famous school of Salernum, Southern Italy, which opened 700 A. D.

Q. Where and when did dentistry advance?.

A. Under the influence of this school, dentistry was practiced more by surgeons and physicians,* whereas it had been previously largely confined tQ charlatans.

Q. When was the antrum described?

A. About the middle of the thirteenth century, by Bruno of Langoburo, who mentioned various operations upon the teeth and antrum nearly four centuries before Highmore.

Q. When was the earliest European attempt to correct irregularities of the teeth made?

A. About the fifteenth century Giovanni d'Arcoli filled teeth with gold and made attempts to regulate them.

Q. Where did Shakespeare obtain his observations in regard to the teeth?

A. From the famous anatomy of Helkiah Crooke, published in 1618.

Q. When and by whom was the first French work published?

A. A work called 4l Le Chirurgien Dentiste" was published by Fauchard in 1728.

Q. Who wrote a similar work in French?

A. Aeubzi, of Lyons.

Q. Who made the earliest great impression upon the profession?

A. Crooke, who in discussing second dentition, remarks that "The shearing (i. e., incisors) teeth, when they do break forth, do thrust the first shearers out before them and issue betwixt the first two, the second and the dog tooth that is next unto them. But if the former teeth will not fall or be not pulled out, or if the latter issue before the first fall, then the latter make their way through new sockets and turn in the upper jaw outward, in the lower jaw inward, so that there seemed to arise a new row of teeth, and this hath deceived many historians and anatomists also."

Q. Who first mentioned supernumerary teeth?

A. Barth Ruspini, a century and a quarter after Crooke, claimed that all teeth which exceed thirty-two may be regarded as supernumerary. In his opinion irregularities of the canines and incisors were attributable to extreme narrowness of the jaws.

Q. Half a century later what did Robert Blake write?

A. He describes supernumerary and inverted teeth.

Q. Three decades after what did Joseph Harris and Joseph Winckworth remark?

A. That irregularities were due to supernumerary teeth.

Q. What causes attributable to irregularities, then advanced, are still defended?

A. Among these causes (still in considerable favor among dentists, laryngologists and general practitioners) may be mentioned, thucnb-sucking, mouth breathing and enlarged tonsils.

Q. What theory was advanced by J. Imrie, six and one-half decades ago?

A. That irregularity is due to want of development of the jaw bones, intemperance of various kinds, combined with artificial modes of living induced by civilization, and sudden change from heat and cold to which the teeth are subject. Rabbit mouth is due to keeping the thumb in the mouth for hours after going to sleep. Underhung jaw is due to sucking the tongue which throws the under jaw from its articulation.

Q. What does he advise about the extraction of teeth?

A. A similar state of the teeth and jaws is induced when attempts are made by the inexperienced to regulate them by extraction of teeth in the upper jaw and neglecting to remove an equal number of the lower.

Q. What was J. Lefoulon's opinion?

A. That the most frequent cause of dental irregularities is the neglect of proper supervision of the second dentition.

Q. What did Thomas Ballard claim?

A. That serrated teeth and projecting jaws were the result of fruitless sucking.

Q. What was Stockton's opinion?

A. That the cause may be found in the form of the palate. Irregularity of position is almost exclusively confined to the five anterior teeth on each side of the median line brought about by the tongue upon the hard palate in sucking or mastication.

Q. What were Nasmyth's views?

A. That the projecting upper jaw was due to thumb and finger sucking. But when both were involved that it was due to arrest of development in the jaw where the expansion of the jaw was deficient.

Q. What changes occurred during the next twenty-five or thirty years?

A. The opinion as to the influence of thumb-sucking* continued to grow.

Q. What opinions were prevalent in 1873?

A. A. A. de Lessert, Thomas Salter and J. W. White believed that thuxnb-sucking was the principal cause.

O. How did Francis Fox view irregularities?

A. That the want of proportion in size of the teeth and jaw bones, or prolonged retention of the temporary teeth, supernumerary teeth., the habit of thumb-sucking, undue pressure from a hypertrophied tongue, and heredity were the causes.

Q. What effect did Helkiah Crooke's summary have?

A. His views influenced investigators about a century and a half afterwards. Thomas Berdmore claimed that the presence of supernumerary teeth or of a double row of teeth is due to the fact that the milk teeth are never shed, notwithstanding the fact that the permanent teeth appear.

Q. What did Joseph Fox claim as causes of irregularities of the teeth?

A. That the most frequent cause is a want of simultaneous action between the increase of the permanent teeth and the decrease of the temporary ones by the absorption of their fangs, most commonly occasioned by the resistance of the nearest temporary teeth.

Q. What did Joseph Murphy believe?

A. That irregularity is due chiefly to the first teeth not having been shed in time.

Q. What are Benjamin James and Parmly's views?

A. They agree with Murphy. Parmly further says that when the permanent teeth are large and growth of the jaw does not proceed in a corresponding proportion, they are found crowded, and overlap each other.

Q. What did G. White find?

A. That irregularities of the teeth are mostly occasioned by the pressure of the temporary upon the permanent, throwing them in the wrong direction.

Q. What are the views of S. S. Fitch?

A. Similar to those of Joseph Fox.

Q. What is the opinion of J. B. Garriot?

A. That the deciduous teeth, by their pressure, often prevent the permanent teeth from arranging- themselves in their proper positions.

Q. What did John Hunter advance as a cause?

A. That the jaws grow at the posterior edges, and that an irregularity is often due to the ten anterior permanent teeth being larger than the ten anterior temporary teeth, while the corresponding part of the jaw is of the same size; therefore in such cases the second set is obliged to stand very irregular.

Q. From observation made upon young pigs, at what conclusions did G. M. Humphrey arrive?

A. That there is no interstitial growth. The five permanent teeth occupy exactly the same position throughout life and all conditional teeth are added to the hind end of the jaw. This hind end is enlarged by the absorption of the anterior coronoid edge and the deposition on the posterior edge where the molars are first formed they are under the coronoid process and are frequently exposed.

Q. What did L. Koecker claim in 1826?

A. That the deformity which consists in shutting the under incisor and cuspidati over the upper, has been produced by the injudicious extraction of some of the teeth of the upper without taking proper care to secure due proportion between the upper and under jaw.

Q. What did Thomas Bell think?

A. That the most usual cause of permanent irregularity is the actual want of sufficient room in the jaw for the ultimate regular arrangement of the teeth.

Q. What is Joseph Scott's opinion?

A. Irregularity arises from, first, a natural want of sufficient expansion in the jawbone at the time of their protrusion ; second, from not extracting the temporary teeth at the proper time; third, from too early extraction of the temporary teeth; fourth, from supernumerary teeth.

Q. What did John Nicholls find?

A. That the deformity may be due to too long persistence of the temporary teeth, or arises from some malnutrition of the teeth or jaws, entirely beyond the previous control of the dentist.

Q. What are the views of M. Maclean?

A. That expansion of the jaw is prevented by premature extraction of the temporary teeth.

Q. What did E. E. Spooner find?

A. That the first and most frequent cause of irregularity is a want of simultaneous action between the protrusion of the permanent teeth and absorption of the fangs of the temporary. The second cause is a narrowness of the maxillary arch, or a want of proportion between the extent of it and the size of the teeth.

Q. What theories did William Thornton advance?

A. That irregularities of the teeth proceed from three causes: First, from natural want of sufficient expansion in the jawbone at the time of the protrusion of the teeth, second, non-extraction of temporary teeth at the proper time ; third, too early an extraction of the temporary.

Q. What views did Mortimer have?

A. That irregularities of the teeth arise from natural and accidental causes. Natural causes arise from the bad conformation of the jaw, so that several teeth are over each other; from the teeth being much larger than they should be; from coming out of order and place; from teeth growing out of the plate or projecting out of the mouth. Accidental causes arise from neglect or ignorance in removing milk teeth too soon, when the second teeth take a direction inward or outward from some internal cause; underhung jaws arise from making faces.

Q. What theories did Charles de Loudes advance?

A. That irregularities are. due to supernumerary teeth, to second teeth being large and maxillary arch too narrow, to early extraction, to too long persistence of the temporary teeth, to shape of the maxillary arch, and to heredity, where the child inherits the jaw of one parent and the teeth of another.

Q. What views did Samuel Ghimes suggest?

A. He spoke of the underhung jaw being due to the upper incisors extending inwards, and in closing the mouth, they come in contact with the lower. This makes the child incline to protrude the lower jaw, which finally becomes habitual and promotes the increase in the length of the jaw itself.

Q. To what does Nessel attribute irregularities?

A. To the premature extraction of the temporary teeth. The alveoli form a bone scar in such cases, which constitutes an obstacle to the advancement of the permanent teeth. In consequence, the permanent teeth come before the jaw is sufficiently expanded to receive them.

Q. Between what years was the theory of mouth breathing most prevalent?

A. Between i860 and 1880, mouth breathing, especially during sleep, formed a prominently discussed etiologic factor.

Q. What was Tomes' opinion?

A. That deformity of the jaws is often caused by sleeping with the mouth open.

Q. What did Catlin, the ethnologist, claim?

A. He made popular propaganda in favor of nose breathing, and ascribed many diseases to keeping the mouth open. Malformation of the jaws and teeth were due to keeping the mouth open, since civilized man is the only animal who keeps his mouth open during sleep. This view still meets with much favor among dentists and laryngologists. It is, however, losing cast with paediatricians.

Q. Sixteen years after Catlin, what views were advanced by W. Mathews?

A. Irregularities were attributable to enlarged tonsils, which necessitated breathing being carried on with the mouth open. They were also due to heredity. The maxilla was smaller in proportion than the teeth, owing to the lessened work of the jaws and teeth among civilized races. Cross breeding played an important part, as did thumb-sucking and lip-sucking; retarded shedding of the temporary teeth and too early extraction of the first permanent molars. The congenital V-shaped jaw is that formed where, previous to birth, the type of upper maxillae is such that its cornua do not diverge posteriorly, but are parallel. As that portion of the jaw already formed never changes its form, the newly added parts will pass off in divergent lines, forming an angle with that previously existing in order to correspond with the increasing width of the base of the skull. The growing tendency exhibited from the time of Crooke to assign constitutional factors important places in the etiology of the teeth and jaw irregularities is noticeable in Mathews. He, while laying stress on local factors, was forced to recognize the importance of constitutional factors. Constitutional factors hence early began to assume considerable importance. John Fuller, while attributing, in 1810, irregularity to long persistence of temporary teeth, also remarked that the upper jaw is often too small for the permanent teeth, this condition frequently resulting in its irregularity.

Q. What w r as Sigmond's opinion?

A. That irregularities are due to natural and accidental causes. Causes are natural, (1) when they result from the jaw not expanding sufficiently to allow the teeth to form a regular circle; (2) when they are larger than the ordinary dimensions; (3) when they do not appear in their proper order and place. Causes are accidental when due to negligence or improper treatment at the time of growth.

Q. What views did Andrew Clarke advance?

A. That irregularity of the teeth is occasioned by want of room in the jaw and not from any effect that the first set of teeth may produce upon them, is evident from the fact that in all cases of irregularity, there is not room to admit of placing the teeth properly.

Q. What were those of J. P. Clarke?

A. That irregularity may arise from too premature extraction of temporary teeth. Disproportion between the teeth and jaws may be occasioned by a natural conformation of the parts, or may be the effect of unnoticed accident. For we seldom found any such disproportion and consequent irregularity in the teeth' of men and animals in a wild state.

Q. What was William Robertson's hypothesis?

A. That deformity is due to inheritance of the contracted jaw of one parent and the large teeth of the other.

Q. What did David W. Jobson suggest?

A. That irregularity is due to smalfeiess of the maxillary arch and the great size of the permanent teeth, and to their situation, part on the inner and of others on outer side of permanent teeth.

Q. What was John Mallan's theory?

A. That the adult teeth being larger as well as more -numerous than the milk teeth, it is obvious that they require a great deal more room, and when the absorption of the latter does not progress equally with the growth of the former, the new teeth are crowded up and are apt to be forced out of their natural position by the resistance of the old. Again, if the permanent prove, as they sometimes do, disproportionately large in comparison with their predecessors, the jaw may not be sufficiently extended to admit of their being arranged in order, in which case some overlap the others and considerable deformity is occasioned.

Q. What was Maury's theory?

A. That the prominence of the upper jaw is due to narrowness of the arch; recession to the anterior teeth.

Q. What suggestion did C. H. Harris make?

A. That infringement of the laws of growth or disturbance of the organs of the face or head may determine improper development of the jaws and bad arrangement of the teeth. Irregularity of the teeth is due to narrowness of the maxillary arch and sometimes to the presence of the temporary teeth.

Q. What does W. K. Brideman suggest?

A. That the tongue, lips and cheek exert no influence in moving the teeth from their original direction. This is due to the shape of the jaw.

Q. What is Sam Harbert's theory?

A. That irregularities of the teeth are due to premature extraction of the deciduous teeth and protrusion of the permanent before the absorption of a deciduous fang. A projection of the lower jaw is attributable to neglect in second dentition. Generally it is supposed to be due to elongation of the jaw, which is almost always an error. When the dental arch becomes contracted at the medial line, giving to the mouth a pointed appearance, it is often the result of premature extraction of temporary teeth.

Q. What is Alfred Canton's opinion?

A. That irregularity of teeth as regards shape, position, direction, crowded condition, etc., is met with more frequently than is supposed to be the case. The causes are chiefly mechanical, depending either on the non-increase in size of the jaw in proportion to the growth of the teeth to be contained in the alveolar arch; on the position of the permanent teeth with reference to the fangs of their predecessor, and lastiy, on the increase in size of one jaw in preference to the other.

Q. What is C. F. Delabarre's opinion?

A. That malformation of denture may be occasioned by defective conformation of the jaw; by simple arrest of development dependent upon the health of the individual; by excess of development of the teeth, though the jaws be in other respects well formed; by rapid development in the dentition of one set, and delay in that of the other; by the too great size of the teeth of one jaw, which do not harmonize with those that are opposite. Some forms of defective palatine arches are hereditary.

O. What was J. R. Duval's opinion?

A. That in a projecting chin, the alveolar arch, in which the incisors and canines are placed, has taken a development upon a parabolic line — greater and more prominent than that presented by the bone. This differs very little from a similar one in the upper jaw, which projects over the lower. Upon 'attention to shedding of the temporary teeth depends the fine arrangement of the lower.

Q. What was Gunnell's opinion in regard t<3 protrusion of the lower jaw?

A. That while in many cases hereditary, it is often brought about in the following manner: The incisors of the lower jaw are cut first, and when the upper ones appear, the lower have nearly arrived at full growth. In closing the mouth, they come in contact with the gum on the inside of the upper incisors, and for relief the lower jaw is thrust out, which condition soon becomes permanent.

Q. W r hat was the opinion of Samuel Cartwright, Jr. ?

A. That irregularities of the permanent are due, first, to non-absorption of the roots. of the temporary teeth in proportion to the rise of those of replacement. Second, to the great difference which commonly exists in the size of the new teeth as compared with those of the first set. Third, to contraction of the arches of the jaws and other malformations of the maxillary and palate bones originating in hereditary, congenital, and other causes.

Q. What were the conclusions of Messrs. Mummery and Nichols, in i860, after observations upon the teeth of primitive races?

A. They found that irregularities of the teeth, and contracted jaws, were rare.

Q. What did Messrs. Coleman and Cartwright's observations show?

A. That the primitive skulls in Kent, England, had well developed jaws and alveolar arches. The teeth still present were remarkably regular.

Q. What opinion did Samuel Cartwright express in 1864?

A. That irregularities result from selective breeding; that they both are congenital and hereditary; that there is very little increase in the anterior part of the jaw after eight or ten years; that if the temporary teeth were to remain, the jaws would not change from those of childhood; that in all cases irregularity of the maxillae are more or less altered in proportion of development, whilst the teeth maintain in regard to size an average development.

Q. What did A. A. Blount suggest?

A. That the remote causes which produce irregularity will be found in the commingling of all nations with national and individual characteristics. The most frequent causes are the result of accident, indiscriminate action of the deciduous teeth, and too early extraction of the permanent teeth.

Q. What did H. Sewell suggest?

A. That protrusion of the incisors is apparently due to an abnormal development of the maxillary bone. Irregularities are due to retention of temporary . teeth, causing permanent teeth to assume an unnatural position; also to malformation of the jaw, which is usually congenital and at the same time hereditary. They may be due, however, to injury and to accidental causes.

Q. What did J. L. Down find?

A. That excessive vaulting of palate is due to arrest of development of the sphenoid or defective growth of the vomer. The defects are development defects, and betoken a cause long anterior to the time when sucking the thumb is practiced, unless that habit be an intra-uterine one.

Q. To what does Kingsley attribute irregularities?

A. Irregularities are attributed chiefly to premature extraction of temporary teeth, marriage between persons of different nationalities, heredity, or disturbed innervation.

Q. What is S. H. Guilford's division?

A. Hereditary and acquired.

Q. What did the author conclude in 1880?

A. That the shape and size of the jaws may be inherited, but the manner of the eruption of the teeth is not transmitted, hence irregularities of the dental arch per se are not inherited.

Q. What other point did he settle?

A. That the muscles of the mouth and cheeks have nothing to do with the production of the V-shaped or saddle arch or their modifications.

Q. What was shown?

A. That the only tissues involved in the production of irregularities are the teeth on the one hand and the jaw bone and alveolar process on the other; that the incisors in the V-shaped arch always protrude, and never in the saddle; that the manner of the formation of irregularity is in the arrangement of the teeth

(no matter what position the teeth take, the alveolar process builds itself about them to hold them in position) ; that there is a decided difference between the deformities produced by thumb-sucking in its various forms and the V and saddle arches. Owing to the jaws being transitory structures with an unstable nervous system, excessive and arrest of development takes place. One jaw may be excessive, the other arrested.

Q. What are some of the causes of an unstabl nervous system?

A. Debilitating, acute diseases of children are noticeably often followed by sudden overgrowth or undergrowth of bone. Cases of pneumonia and measles are followed by dental and maxillary deformities. Inherited or acquired neuropathic states are also evinced at the periods of stress marked by dental evolution or involution. Irregularities are due to constitutional origin, developing with the osseous system, and to local origin. Irregularities cannot occur until the teeth have erupted (as nothing can exist except it be present). This shows their relation to each other and to the jaw. Deformities always commence at the sixth year, and are completed by the twelfth. The forward movement of the posterior teeth produce the same results as arrest of development of the maxilla. The vault is not contracted by mouth breathing. Contracted arches are as common among low vaults as high, but appear high because of the contraction. Mouth breathing (due to hypertrophy of the nasal bones and mucous membranes, deformities of the nasal bones, adenoids, or any pathologic condition producing stenosis) does not cause contracted jaws, but like V ^-se is due to neuroses of development.

Q. What is Colyer's summary?

ON IRREGULARITIES OF THE TEETH. 'IT

A. The opinion of previous writers into the statement that the causes which produce irregularities of the teeth are general and local.

Q. In 1901, to what did Arbuthnot Lane call attention?

A. To the association of deformities of the alveolar process and constitutional deficiencies (like those of the chest) referring the deformities to the action of local factors and ignoring the underlying constitutional element.

Q. Give a summary of the theories in the order in which they have been advanced to 1880.

A. Irregularities of the teeth were early recognized and attempts made toward correction. Irregularities were charged: To too long retention of the temporary teeth, too early removal of the temporary teeth, to supernumerary teeth, narrow jaws, inverted teeth, thumb-sucking, mouth-breathing, enlarged tonsils, want of development of the jaw bones, intemperance, heat and cold, sucking the tongue, extracting teeth on the upper jaw and neglect to extract the same number on the lower, the influence of the tongue, lips and cheeks, the form of the palate, tongue hypertrophy, heredity, too great permanent teeth for the space, pressure of the temporary against the permanent, want of interstitial growth, from removal of the temporary teeth (the bone scar prevents the permanent teeth from erupting regularly) sleeping with the mouth open, cross breeding, constitutional factors, congenital states, early decay and loss of the temporary teeth, non-absorption of the roots of the temporary teeth, selective breeding, arrest of development of the sphenoid or defective growth of the vomer, artificial life, disturbed innervation.

Chapter II Heredity

Q. What are L,uys' views as to heredity?

A. That the individual that comes into the world is but one link in a long chain which is unrolled by time, and the first links of which are lost in the dim past.

Q. What are the antecedents of the individual?

A. He has not merely two parents but the ancestors behind him.

Q. Do these ancestors represent the same, or different types?

A. These two parents may represent ancestors of very different types, whose qualities, seemingly absent in the parent, v/ill appear in the descendant.

Q. Do the relative functions of the sexes become a factor?

A. They are a potent factor to be taken into consideration in estimating its influence.

O. What part does the female play?

A. The original function of reproduction, that of cell division, is the part of the female.