_The removal of lower molars when a portion of the crown is standing, but the decay has progressed below the gum_ on either the buccal or the lingual aspect, is carried out with root forceps of shape shown in fig. 27. A condition similar to this in upper molars and the method indicated for their removal were referred to on page 27. The principles enumerated there apply equally to the removal of lower molars, so that it will not be necessary to repeat them. The main points to bear in mind are, to apply the blades of the forceps to the stronger root, and to use the principal force in the direction of the weaker wall. _Where the roots of molars are still united_, root forceps should be used, the blade being first applied to the lingual surface of the stronger root. A firm hold having been obtained, the root may be removed by employing force in a manner similar to that employed with ordinary molar forceps. In this way both roots will usually come away together. If, however, only one root is extracted, the remaining one can easily be removed, either with the same forceps or a curved elevator. The curved elevator (fig. 49) may be employed either by placing it against the root, and so forcing it into the socket of the root already removed, or by placing the blade in the socket of the extracted root, forcing the point of the instrument through the intervening bone and then elevating the remaining root. _With roots of lower molars which present great resistance_, forceps with cutting blades may be used (fig. 32). The blades are inserted on the lingual and buccal aspects of the arch in such a manner that the points pass into the space between the roots. The handles are then closed and an attempt is made to remove the roots in the ordinary way, but should this prove unsuccessful the handles must be forcibly closed, so as to divide the roots which can then, as a rule, be removed with ordinary root forceps. The value of splitting roots in a case similar to that shown in fig. 33 is apparent, for, as will be seen, it allows each root to be removed in the line of its inclination. [Illustration: FIG. 32.] _In those cases where the roots are separated_ their removal is carried out with root forceps, an inward and outward movement being usually sufficient. The roots of third molars are best removed with a straight elevator. The _modus operandi_ is similar to that used in extracting the whole tooth. [Illustration: FIG. 33. (_a_) Lower molar with divergent roots. (_b_) The dotted lines show the direction in which the root can be removed if the tooth is divided as suggested in the text.]