Interceptive orthodontic treatment using passive self-ligating appli- ances with individualized prescriptions – Phase 1: Case report

Henrique Mascarenhas VILLELA

Introduction: The mixed dentition is one of the stages of occlusion development, in which changes occur not only in relation to tooth, but also to facial growth and development. At this time, several types of malocclusion manifestations may arise, and it is an excellent time to intercept problems that may interfere with the correct growth and development of the dento-maxillary complex. Among the various types of interceptive treatments, the use of passive self-ligating fixed appliances with variable prescriptions is an excellent option to perform partial alignment and leveling in some teeth. In selected cases, this mechanics can reduce the indication for serial extractions or rapid maxillary expansion. Its indication is more precise for cases in which there is crowding with normal size teeth, in the presence of arch atresia with buccal-lingual compensation. Objective: This article shows a clinical case that used, as an interventional treatment option in the mixed dentition, passive self-ligating brackets and variable torques to correct severe crowding in the mandibular incisors, obtaining space for the lateral incisors with the need for transversal expansion of the dental arches. Results: Within two years of treatment, the incisors aligned with a slight increase in their inclination. At the three-year post-treatment evaluation, with the permanent premolars, canines and second molars already erupted, the space gain and the position of the incisors remained stable even without retention. The most significant orthodontic effect was the correction of severe crowding in the lower arch using the LOW torque prescription. There was a control of buccal tipping, with initial IMPA of 95o to 100o and after three years IMPA = 102o . In the upper arch, there was no major buccal movement of the incisors, with an initial 1.PP of 112° to 115°, and after three years there was no change. Interceptive treatment corrected the problems of tooth alignment with normalization of the horizontal and vertical overjet of the inci- sors, providing a favorable condition for natural mandibular development, with a reduction of the sagittal discrepancy between maxilla and mandible (ANB angle: initial = 8.0°, final = 6.0°, post 3-year control = 3°). Conclusion: This interventional treatment strategy was efficient in the correction of severe crowding of mandibular incisors in the mixed dentition, with tipping control of these teeth and stable results after three years without retention.

Keywords: Interceptive orthodontics. 4x2 leveling. Mixed dentition. Self-ligating appliances. Variable prescriptions.

How to cite: Villela HM. Interceptive orthodontic treatment using passive self-ligating appliances with individualized prescriptions – Phase 1: Case report. Clin Orthod. 2021 Aug-Sept;20(4):74-98.

Tuesday, September 21, 2021 20:40