In _patients predisposed to hæmorrhage_ extraction should be if possible avoided; but, if the removal of the tooth be absolutely necessary, prophylactic treatment should be pursued for three or four days previous to the operation by the administration of one or other of the remedies previously mentioned. A new styptic, consisting of fibrin ferment 1 to 10 to which 1 per cent. of calcium chloride has been added, is said by Walsham to act only on the blood, not on the tissues, and to be perfectly aseptic. It was found to be effectual in arresting hæmorrhage after the division of all the veins except the common jugular in a dog’s neck. The tooth should be extracted in the early morning, as we then have the day before us should hæmorrhage occur. Some hæmostatic should be administered at the time of the operation and the socket plugged at once; for it is most important to remember that in these cases it is far easier to prevent the hæmorrhage occurring than to arrest it when once it has commenced. The subsequent treatment will consist in the continued administration of hæmostatic drugs. (_f_) =Injury of the arteries in the neighbourhood of the teeth.=--Wound of the _lingual_ artery has been referred to under the heading of injuries to the tongue. Laceration of the _ranine_, _anterior and posterior palatine_ arteries may also occur. Such accidents are usually the result of the forceps slipping and are therefore avoidable. Treatment consists in pressure or in twisting or tying the divided vessel. In the case of the _anterior or posterior palatine artery_ it may be found necessary to plug the foramina which give passage to these vessels. (_g_) =Pain following tooth extraction.=--The causes giving rise to pain following the extraction of a tooth are:-- (1) _Incomplete extraction of the tooth_, more especially when the remaining portion contains an exposed pulp. (2) _Too rapid healing of the orifice of the socket._--It sometimes happens that the margins of the wound left after extraction unite very early, and when this occurs the discharges which naturally come away from the granulating surface at the base of the socket, have no exit; the consequence is that they are retained and set up a local traumatic inflammation, leading to swelling of the surrounding tissue. (3) _Suppuration in the tooth socket._--This may be due in the first instance to the use of dirty forceps, and under such circumstances it may be classed as a poisoned wound. An examination will reveal the presence of greenish putrid pus, while the tissue around will be much inflamed, and the portion immediately bordering the wound will have a tendency to slough. A condition of this kind is often seen in hospital nurses and medical students and is no doubt due to infection met with in their daily duties.