(_d_) =Lower Molars.=--Lower molars have two roots, placed anteriorly and posteriorly. The roots are much flattened and have a tendency to curve backwards, this being well marked in the second and especially so in the third molar; a fusion of the two roots is at times met with in the second and frequently in the third molar. A section of a lower molar at the neck shows both the buccal and lingual aspects to be composed of two segments of a circle touching each other at one extremity; the anterior segment being slightly the larger (fig. 28). Each blade of the forceps used for these teeth should possess two grooves, [Illustration: FIG. 29.] [Illustration: FIG. 30.] separated by a projection which fits into the division between the anterior and posterior roots; for all practical purposes the blades may be made of the same size, so that one instrument will suffice for both sides of the jaw. The instrument best adapted for the removal of these teeth is shown in fig. 29, though some operators prefer the shape illustrated in fig. 30. The advantages of the former over the latter may be briefly summed up as follows: (1) A clear view of the tooth and its surroundings can be obtained during the whole period of removal. (2) Force can be applied with greater advantage. (3) The alveolus can be easily embraced by the fingers, or by the finger and thumb of the left hand. (4) In removing the tooth from the socket a slight backward movement can be employed. One disadvantage of shape fig. 29 is that it is difficult to employ much inward movement, and therefore, for teeth lying inwards, namely, with the crown directed towards the tongue, hawk’s-bill-shaped forceps cannot easily be used. Another disadvantage is that the extent of inward movement is limited by the proximity of the upper teeth, and in case of trismus it is often better to use straight forceps (fig. 30). In cases where there are also much swelling and rigidity of the cheek the straight forceps cause less inconvenience to the patient. In removing lower molars with forceps, the inner blade should be first applied and then the outer, care being taken to get the points of the blades between the interspace of the roots. For severing these teeth from their attachments, a slight inward movement should be first made, followed by one well outwards, this inward and outward movement being repeated if necessary. The removal of the tooth from its socket is carried out by force used in an upward and outward direction. The upward force exerted upon lower teeth should always be well under control, as not infrequently the resistance is very suddenly overcome, and, if such precaution is not taken, there is danger of striking the upper teeth with considerable force. [Illustration: FIG. 31.] As previously pointed out, the roots of these teeth are at times curved a little backwards so that it is often needful in removing the teeth from their sockets to twist the forceps in a curved direction backwards.