The next thing is to take a mould of the lower jaw in wax softened by heat, holding the wax in an ordinary dentist’s tray. From this mould a plaster cast of the jaw is made. If the line of teeth be uneven in the cast, it is to be sawn through, the pieces raised to the right level, and cast again. In this cast a vulcanite plate is made exactly fitting the teeth (see fig. 24). The margins of the mould or splint should be carried down below the line of the gums, to grasp the jaw beyond the alveolar border; and when the fracture takes place behind the teeth, its outer side should be prolonged backwards as far as the muscles will allow, to prevent the displacement of the anterior fragment outwards which muscular action produces in these fractures. Holes should be made in the top of the splint, to permit a stream of water to be sent between the splint and the teeth daily, for cleanliness. Also, in difficult cases, a hole should be cut opposite a tooth in each fragment, for ascertaining from time to time that each part continues in its proper position while the splint is worn. Metal is used for the plate by English dentists, instead of vulcanite. It can be made thinner, and is less brittle than the latter. The perfect fit thus secured suffices, in simple fracture, to keep the parts in close apposition; while the movements of eating and speaking are very little interfered with. [Illustration: Fig. 25.—Showing the method for supporting externally the jaws in the splint, when the teeth are not fastened to it by screws, E. Upper wing; G. Lower wing; H. Mental band to keep the jaw up in the splint; I. Neck-strap to keep the band back; K. Balance-strap to hold skull-cap in place. The upper wings are of course dispensed with, when a single splint only is used. ] When the displacement is considerable the fragments are held in place by riveting one or more teeth to the cap, or, when circumstances prevent support being obtained in this way, external support is supplied to the splint by steel wings, fixed into the splint at the angles of the mouth (see fig. 25), and carried outside the cheek to the angles of the jaw. A piece of stout jean or canvas, cut to fit under the chin, is then connected with these wings, and also fastened by a tape behind the neck. If the case require that a bearing be made on the upper jaw as well as the lower one, as in fracture of both jaws in edentulous persons, the two splints are articulated behind, so that they may open and shut with the lower jaw. Each piece then carries a wing, the lower one supporting a chin-piece, and the upper one being connected by strings attached at the temples to a close-fitting skull-cap. The skull-cap is prevented from slipping forward by connexion with a strap fastened to both shoulders. =A fractured Rib= is very well treated by strapping the injured side alone, without enrolling the chest in a tight bandage, which harasses the patient by impeding respiration.