Nothing, perhaps, tests the skill of a good operator more than the extraction of a misplaced or impacted tooth, and although it is impossible to give anything like a complete list of the various malpositions met with, those most commonly seen will be mentioned, and the usual method for removing such teeth indicated.

(a) Upper Central Incisors.—An irregularity of this tooth calling for removal is shown in fig. 37.

The extraction is best carried out with an instrument similar to that shown in fig. 38, the fine inner blade being applied on the palatal side and the broad blade on the labial. Extractive force should be applied principally in the outward direction, and if this is not sufficient, slight rotary movement should be tried. In cases where there is less room between the approximal teeth, the projecting tooth may be removed with a pair of straight forceps (fig. 17), the blades being applied to the mesial and distal aspects of the root. The blades should not be driven very far up, and the loosening of the tooth should be accomplished by slight rotary motion, in using which care should be taken to avoid loosening the approximal teeth.

(b) Upper Lateral Incisors lying internal to the arch, as shown in fig. 39, can be removed with the forceps shown in fig. 38, by placing the fine blade on the labial and the broad blade on the palatal side of the tooth. Extractive movement should be made inwards, followed by very slight outward movement; this failing, rotation should be tried, but as pointed out on a previous page, this form of movement is not so suitable for lateral incisors as for centrals.

(c) Upper Canines placed high in the arch, as shown in fig. 40, may be extracted with a straight pair of forceps (fig. 17), the blades being placed on the mesial and labial aspects of the root. Extraction of such teeth is very difficult. Slight but firm rotation may first be tried; if this fails to loosen the tooth, slight lateral movement may be attempted, the force being applied towards and then away from the median line of the mouth.

(d) Upper Bicuspids misplaced, as shown in fig. 41, can be removed with forceps, as shown in figs. 18 and 22, the blades being applied on the anterior and posterior aspects of the tooth. Force should be applied in a backward and forward direction, the movements being repeated and persevered with until the tooth is loosened in its socket.

A bicuspid placed as shown in fig. 42 can be removed with forceps similar in form to those depicted in figs. 18 and 22, with the outer blade strong but narrow. The extractive movement should be made mainly in an inward direction.

(e) Lower Central Incisors placed similarly to that shown in fig. 43 may be removed with ordinary lower root forceps (hawk’s-bill pattern), the blades being placed on the mesial and distal surfaces of the root, and movement applied in a direction to and away from the median line of the mouth. When the crowding is not so extreme as shown in fig. 44, forceps of the hawk’s-bill pattern with a strong but narrow inner blade should be used (fig. 45), and the principal extractive movement made in an outward direction. For an incisor placed as shown in fig. 47, the narrow blade should be the outer one (fig. 46), and the principal force should be applied in an inward direction.

(f) Lower Bicuspids placed as in fig. 48 are

most difficult teeth to remove. One of the most useful instruments for their extraction is a pair of upper root forceps (Read’s pattern, fig. 22), which should be held so that the curve of the blades is downwards. The blades should grasp the root on its anterior and posterior surfaces. Slight rotary movement may first be attempted, followed by lateral motion. These movements may be persevered with until the tooth is found to yield. Too much haste may lead to a fracture, which would be extremely difficult to deal with.

In cases where the crowding is not so great, and the tooth is more in the normal line of the arch, a forceps with a narrow outer blade will suffice (fig. 46). Extractive force should be used principally towards the median line of the mouth, and this may be combined with slight rotary movement.

(g) Impacted Lower Third Molars are amongst the most difficult teeth to extract. Where the tooth is deep-seated, the gum should be pushed aside by careful packing, and as clear a view of the tooth as is possible obtained. For removing these teeth it is difficult to give any rules, as each case must be treated on its own merits.

As useful an instrument as any for their removal is a curved elevator (fig. 49), the blade of which can often be inserted under the crown, and assuming that good leverage is thus obtained, the tooth can be prised up. Sometimes the tooth is firmly embedded in the bone. In such cases a clear view of the tooth may be obtained by gradually packing the soft tissues apart, the periosteum covering the alveolus should then be raised, and the bone surrounding the tooth cut away with suitable instruments. The tooth, when freely exposed, should be removed with an elevator or forceps.

The wound resulting must be carefully packed and treated as described on page 85.