(d) The Removal of the wrong tooth.—The removal of the wrong tooth may occur and is naturally due to carelessness on the part of the operator. Should this accident arise, the tooth must be immediately replaced and if necessary secured with a ligature. If the pulp subsequently shows signs of degeneration or inflammation it should be removed and the canal treated and filled.
(e) Removal of a neighbouring tooth.—This may occur and is generally due to a crowded arrangement of the teeth. The accident seems to occur most frequently with the removal of the first permanent lower molar, the neighbouring tooth usually involved being the second bicuspid which is simultaneously dislocated from its socket. This accident can be avoided by placing the thumb on the tooth which shows a tendency to move, and exerting only as much force in the removal of the tooth which is being extracted as can be controlled by the thumb. If a neighbouring tooth is removed it must be replaced and treated in the same manner as described above.
(f) Removal of an unerupted bicuspid.—This may be an avoidable or an unavoidable accident. At times the developing bicuspid is so firmly embraced by the roots of the deciduous molar that during the extraction of the latter tooth the bicuspid is removed—such an accident cannot be avoided. It is an avoidable accident when it occurs during the extraction of the roots of a temporary molar and arises from using too much force. As previously pointed out it is best to leave the fractured roots of temporary molars alone unless they can be easily removed.
(g) Breaking one tooth in extracting another.—In the extraction of lower teeth with hawk’s-bill forceps the upper teeth may be fractured. This accident is most likely to occur to the inexperienced, and arises from the tooth leaving its socket suddenly, due frequently to the extracting force being used in an upward rather than an outward direction. It may, however, occur when a lower tooth has been more than normally resistant. In all such cases it is well for the operator to be on guard by keeping the thumb or a finger of the left hand over the joint of the forceps.
Also in using the elevator an adjacent tooth may be fractured.
(2) DIFFICULTIES, COMPLICATIONS AND SEQUELÆ CONNECTED WITH THE JAWS.
(a) Fracture.—The fracture and removal of a small piece of the alveolus is not an unfrequent accident which is fortunately by no means serious. It is sometimes unavoidable but at other times is due to getting the blades of the forceps on the outer sides of the alveolus instead of between the bone and the root of the tooth.
Extensive fracture is sometimes seen, for instance in a case that came under my notice at the Dental Hospital of London an unqualified person in removing the first lower right permanent molar fractured the bone in a horizontal direction so that the second and first bicuspids with the canine were completely separated from the body of the bone. Mr. Salter[5] gives an account of an extensive fracture of the jaw which occurred in a lady æt. 35. The fracture occurred in connection with the removal of the superior central incisors. The right central incisor required some force for its removal, and when it came away the whole of the front of the alveolus was firmly attached to the root. In removing the left central incisor considerable force was required during the exertion of which the bone was fractured. On examination of the parts the mass of bone corresponding to the intermaxillary bone was found to be merely held in place by the soft tissues. “A vertical fracture extended from the side of the canine up to the root of the nose, then nearly horizontally across to the opposite side, being connected there with another vertical fracture. The lesion passed completely through the jaw from before backwards, and there was a wound in the palate three quarters of an inch from the alveolar border, through which was considerable hæmorrhage.” A still more severe example of fracture during extraction of teeth is recorded by Mr. Cattlin,[6] where in an attempt to remove a third upper molar with an elevator the tuberosity of the maxilla, a portion of the floor of the antrum and part of the sphenoid were fractured.
Fracture of the maxilla tuberosity may occur during the removal of the third upper molar, and Mr. Nicol[7] records such an accident during the removal of the second upper permanent molar. In a case recorded by Mr. L. Matheson[8] a transverse fracture of the maxilla occurred in a line between the first and second permanent molars during the removal of the first-named tooth.
Direct transverse fracture of the horizontal ramus of the mandible due to extraction of the teeth has also been recorded.