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sition possible. Eyelets in the comers of the bands were tied to the archwire as needed for rotational control, as on the distal of the upper left central incisor.

Fig. l2-4 The labiolingual appliance, widely used until recent year but now obsolete, combined a heavy maxillary labial arch like Ange's E-arch with a heavy mandibular and occasionally maxillary lingual arch to which fingersprlngs and ligature ties were attached, as shown here. Only the first molar, teeth were banded.
Begg's adaptation took three forms: (l) he replaced the precious metal Ribbon arch with high strength 16 mil stainless steel wire as this became available in the late 1930s; (2) he retained the original Ribbon arch bracket, but turned it upside down so that the bracket slot pointed gingivally rather than occlusally; and (3) he added auxiliary springs to the appliance for control of root position in the resulting Begg appliance (Fig. 2-6, friction was minimized because the area of contact between the narrow Ribbon arch bracket and the archwire was very small and the force of the wire against the bracket was also small. Begg's strategy for anchorage control was tipping/ uprighting (see Fig. 10-27).

Fig 12-5 The twi-wire appliance used two strands of 10 mil wire for initial alignment of the incisor teeth. Incisors and But molars had fixed attachments (here, plastic brackets), but canines and premolars were not usually banded. A heavy tube extending forward from the first molar was used to protect the delicate twin wires.

Fig 12-6 The Begg appliance is a modification of the Ribbon arch attachment, into which round archwires are pinned. A variety of auxiliary archwirs are used in this system to obtain control of root position.
The Begg is a complete appliance in the sense that it allows good control of crown and root position in all three planes of space. The greatest difficulty in using the appliance comes in the final stage, where it can be difficult to precisely position the teeth.
Combinations of Begg and Edgewise appliances have been proposed on many occasions. At present, there are two ways to retain some of the tipping/uprighting mechanics used with the Begg appliance while taking advantage of rectangular archwires in a rectangular slot for the finishing stage. One is to use a bracket with both a Ribbon arch (Begg) slot and are Edgewise slots; the other is to use a modified bracket that allows tipping in one direction, so that the rectangular slot is available for both root uprighting and torque (Fig. 12-7).
• Contemporary Edgewise: the Modern Appliance
The contemporary Edgewise appliance has evolved far beyond the original design while retaining the basic principle of a rectangular wire in a rectangular slot. Major steps in the evolution of Edgewise appliances include:
Automatic Rotational Control. In the original appliance, Angle soldered eyelets to the corners of the bands. so a separate ligature tie could be used as needed to correct rotations or control the tendency for a tooth to rotate as it was moved (see Fig. 12-3). Now rotation control is achieved without the necessity for an additional ligature by using either twin brackets on the labial surface (Fig. 12-8) or single brackets with extension wings that contact the underside of the archwire (Lewis brackets) (see Fig. 12-33) to obtain the necessary moment in the rotational plane of space.

Fig 12-7 Modified brackets to allow a combination of Be