A tooth having been fractured, the patient should be made to rinse the mouth until the bleeding has ceased, the socket should be dried with cotton-wool, and the position and edge of the root defined with a probe before attempting to remove the fractured portion. It is neglect of these steps that so often leads to failure to remove the remaining portion of a fractured root. Too many attempts to remove a fractured root should not be made; if a second endeavour proves fruitless, the patient should be dismissed and a fresh attempt, if necessary, made after a period of one or two days, as the tooth will probably then be looser from inflammatory trouble, moreover, the hæmorrhage having ceased, it will be possible to obtain a clearer view of the root. Before, however, dismissing the patient, an anodyne mouth wash should be prescribed, and the pulp if exposed touched with carbolic or nitric acid. The lower third of a root may generally be left without fear of unpleasant consequences; but it is always well to inform the patient when any portion of a tooth is allowed to remain in the jaw, as such knowledge may be of assistance should any trouble arise at a subsequent date. (_c_) =Crowded and irregular teeth.=--The removal of these has already been referred to in Chapter III. (_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.