TN brackets are used in individual cases and are removed and re-glued before final completion, it is only a transitional bracket. In the following cases 1, deep overdenture (1) Angle III deep overdenture cases: because the sepp curve is larger, and the upper and lower teeth contact closely, Begg and square wire brackets thicker, the upper and lower teeth bite teeth together, can cause the brackets to fall off, so can not be bonded Begg or square wire brackets, can first use the plane guide plate movable aligner, depress the lower front teeth, to have some clearance, the use of TN brackets are thinner, bonded to the lower anterior teeth, and then use titanium wire to depress the lower anterior teeth with a rocking chair arch to open the bite to complete the orthodontic treatment. (2) Patients with antitussive teeth have more serious deep overdentures, resulting in the lower incisors occluding the upper teeth with a tight labial surface. Such patients can be bonded with photosensitive material on the premolar and molar surfaces of the lower teeth, open the bite, bond the TN brackets on the upper teeth, and play the rocking chair arch on the lower teeth to open the bite. 2, anterior tooth twisting (1) anterior tooth crowding twisting: bonding TN brackets on the twisted teeth, after the crowded teeth open enough gap by expanding the arch or extracting teeth, loosely tie the 0.012 titanium wire into the TN brackets, so that the arch wire is gradually located in the brackets, to achieve the purpose of correcting the tooth alignment twisting. (2) simple two incisors near the middle of the twist: such cases are mostly seen in children during the period of tooth replacement, the lateral incisors have not yet erupted, after the two incisors bonded TN brackets, take 0.014 Austrian wire, in the middle section of the arch wire ring spring, and away from the tooth surface to form about 160 ° obtuse angle, which can increase the elasticity and flexibility of the arch wire, conducive to the correction of tooth twist, in the two ends of the arch wire play “8 “This will increase the elasticity and flexibility of the archwire and facilitate the torsional correction of the teeth.