MOVING MURIEL
TEETH P.
OVER
THE
L.D.S.,
MICHAELIS,
BITE*
ENGLAND
I
T IS the widespread belief among dental surgeons that it is necessary to open the bite, usually by capping some of the teeth, in order to move buctally a tooth which is lingually misplaced or “inside the bite.” As a generalization this is erroneous, but I am assured of its prevalence by Mr. Chapman’s reply when I mentioned this communication to him. He told me that the idea is such a fixed one that unless one made oneself very convincing, one would not be generally believed. The illustrations will show what I mean and will prove that the movement can be accomplished without opening the bite. I have chosen these three particular cases because they exemplify the type of irregularity which apparently, at any rate to the timid among us, cries out for the opening of the bite. Also, because the treatments carried out include the use of bot’h fixed and removable appliances-and it is the user of removable appliances who is the harder to convince. The habitual user of finger springs on lingual and buccal bows is already among the converted. The illustrations are intended to show the point in question only. The models show other irregularities, which have or have not been treated as the cases demanded; but we are not concerned with those here, and I shall ask you please t,o ignore them. Fig. 1 shows a case in which the left permanent lateral incisor and deciduous canine are well inside the bite, and the left permanent central incisor, although rotated and lingually misplaced, is in a more or less edge-toedge occlusion wit,h the mandibular central. Fig. 2 shows t,he same case eleven mont,hs later. There had been no treatment in the interval owing to illness, and you will see that the central incisor is more or less normal in position, but that the lateral incisor is still lingually misplaced. Treat,ment to move the lateral incisor buccally was accomplished by means of a removable vulcanite saddle plate carrying a platinized gold bar lingual to the incisors, on tvhich was soldered a finger spring exerting pressure at the neck of the lateral incisor. Anchorage was obtained by vvire cribs round 6 ( 6. carrying Visick clasps. Fig. 3 shows the posit,ion of the lateral after treatment. Fig. 4 shows a lingually misplaced canine erupting rather late. Tlris was treated by a similar plate, with a result as shown in Fig. 5. Fig. 6, which sboms the third case, takes rather an unfair advantage of you, I am afraid, because T have not got the final model as yet. The case is under treatment, and if members are interested I shall gladly show the result later. It is being treated with fixed appliances, two lingual bows carrying finger springs. I shall ask you to believe that so far all is going well. *Transactions
of British
Society
for
the
Stuci?; 575
of
Orthodontics,
1932.
In none of these cases has the bite been opened at any time, and treatment along these lines, a.s opposed to one which necessitates opening the bite. obviates unnecessary interfarrnc(k with t tic occllrsion and It1inimixes t 11~ tliscomfort of the pxticllt. II also allows ill f IIC ceaseof a rc~lllovable appliiln~+i~. caf it plate being SO stl;lpe?tl lo c‘olll(’ ill lvitll a minimu ctt’ 1lPlllZi1 liSSll+‘. iS
Fig.
5.
(!OlltirVt
Fig.
6.
The whole misconception probably arises from our failing the fact that the teeth are not normally kept clenched. Even closed the maxillary and mandibular teeth are slightly apart; not apparent on our models we are likely to overlook it. The
to appreciate with the lips but as this is difficulty is in
Moving
Teeth Over the Bite
Xi?
that way a psychologic one, and unless we recognize this essential difference between the model, which is passive, and the mouth, which is active, we are likely to perpetrate the fallacy of treating a model instead of a mouth. DISCUSSION
Mv. H. G. Watlcin said that he had had one case in a fairly young child of a maxillary central incisor inside the mandibular central incisor, with rather a large overbite. Without trying to gag the bite at all, but slowly moving the maxillary incisor forward, he had found that the mandibular central incisor had moved at the same rate by occlusion and had kept in front of the maxillary tooth, so that the speaker had not succeeded in getting the maxillary central over the mandibular by this method. He admitted that it was very seldom necessary to gag the bite, but there were times when it was so, particularly when there was a very large overbite in the front. In another of his cases on one side an upper molar occluded lingually and on the other side the molars occluded normally. He had had four teeth on a. bow on one side working against the lingually placed molar on the other; the four teeth had all moved out, leaving the molar on the other side still biting lingually.
the
Dr. Broderick patients were
inquired, whether unable to close their
Yr. 12. Cutler (Honorary characteristic of these patients for two or three days, though marking the time of transition
there was not a certain length of time during molar teeth, even if it were only for an hour
which or two.
Secretary) added to Dr. Broderick’s question that it was to complain of the teeth that were being moved being tender treatment might be going on for some weeks, this tenderness when the bite was edge to edge.
Mr. AS’. P. St. J. Steadman doubted whether the last remark was quite correct. He thought that the tooth, as it was moved, became tender and the patient bit in such a way that he bit on the tender tooth. It was a bite of accommodation. The tooth was never quite edge to edge, because that would imply that it was shorter when it was being moved over the bite. It was, however, quite easy to move the teeth laterally over the bite. The President related that Mr. Fox, Society, of a young lady who had desired on the lower plate, and had said that on her The case had shown what could be done by Mrs. Michael&r, in would rouse such a storm as Mr. Watkin, but she denture to prevent the She felt open the bite. temporomandibular joint, teeth from moving forward during which the patient Dr.
Broderick
asked
a very old member, had shown a case, to the to be married. He had fitted an inclined plane wedding day she had looked “perfectly lovely. ” the cooperation of the patient.
reply, said that she had not anticipated that her communi’cation of protest. She did not like to contradict so senior a member suggested that if an appliance had been put in the mandibular teeth from moving forward, it would have been unnecessary to that opening the bite would do more harm possibly even to the than the wearing of another appliance to prevent the mandibular She did not know the length of the time at the same time. could not close his teeth, but she had not heard of any complaint. whether
it
would
be
hours
or weeks.
Mrs. JKtitilis, answered that it could not be very long, but that she could not give an authoritative answer, except that she had not heard of any complaints of inability to close. If the finger-springs did not exert too much pressure, there should be neither pain nor tenderness in the tooth being moved. None of her patients had complained of pain, two or three months had been taken for each tooth, but the process had not been hurried; and there had been a very slow finger-spring movement.