TAD‐assisted Lingual Retractors

Clinical Application and Biomechanics of Various Lingual Retractors with Temporary Skeletal Anchorage Devices: A Narrative Review

“…The C-lingual retractor (CLR) was introduced by Chung et al [1,10,18]. Kim et al treated Class II severe anterior openbite malocclusion using CLR and TPAs in the upper dentition and horseshoe mechanics in the lower dentition [11], and there was a decrease in lip protrusion and facial convexity due to the retraction of the anterior teeth.…”

“…The two lever arms are placed on both canines [10][11][12]25,26] or between the central and lateral incisor [2,9,[27][28][29][30], such that the force passes close to the CR of the anterior teeth and the fabricated retractor is bonded to the lingual surface of the anterior teeth. (Figure 1) To reinforce intra-arch anchorage, a transpalatal arch (TPA) with soldered hooks is fabricated with a 0.032-inch or 0.036-inch SS wire on both the first and second molars (Figure 2a) [1,11,12,25]. When absolute anchorage is required during retraction of the anterior teeth, TSADs, such as miniscrews (Figure 2b) or C-palatal plates (Figure 2c, Jin Biomed, Bucheon, South Korea) are inserted in the palatal area [1][2][3]9,27,29,30].…”

“…(Figure 1) To reinforce intra-arch anchorage, a transpalatal arch (TPA) with soldered hooks is fabricated with a 0.032-inch or 0.036-inch SS wire on both the first and second molars (Figure 2a) [1,11,12,25]. When absolute anchorage is required during retraction of the anterior teeth, TSADs, such as miniscrews (Figure 2b) or C-palatal plates (Figure 2c, Jin Biomed, Bucheon, South Korea) are inserted in the palatal area [1][2][3]9,27,29,30]. Since the appliances are not bonded to the posterior dentition when using the CLR with TSADs, the CLR is useful when the occlusion of the posterior dentition is normal and movement of the posterior teeth is desired to be minimal.…”

“…To prevent anterior torque loss during retraction, helical torquing springs are positioned to contact the mini-implants on the posterior palatal slope or allow the application of intermaxillary elastics. The lever arms are fabricated close to the height of the estimated CR of the maxillary anterior teeth and soldered to the lingual connecting arch (Figure 3) [1,2].…”

“…First, because it is located on the lingual surface of the maxillary anterior teeth, it is invisible; therefore, there is no concern about compromised esthetics during the retraction of the anterior teeth [1][2][3]. Second, compared to the conventional bracket, which requires aligning and leveling before the retraction of the anterior teeth, the lingual retractor can address a patient's chief complaint of an anterior protrusion at an early stage because it retracts the anterior teeth from the beginning [1,[3][4][5]. Third, it can avoid round tripping of the anterior teeth and distal tipping of the posterior teeth due to the friction between the archwire and bracket in the conventional lingual orthodontic system [5].…”