Original articleEctopic canine control with conventional brackets
Introduction
Despite the fact the self-ligating brackets were first introduced in the early 1930s [1], it is only in recent years that this type of bracket has become popular among orthodontists worldwide [2]. Self-ligating brackets users state the main advantage of this type of appliance is reduced friction 3, 4, 5. It is also maintained that, in contrast to conventional appliances featuring elastic or metallic ligatures, self-ligating brackets permit reduction of the resistance to sliding, consequently consenting the use of lighter forces to achieve dental movements 6, 7. This means that the risk of compromising the periodontal vasculature is avoided, the musculature of the patient is not damaged and the arches can be expanded in a physiological fashion [3]. Badawi et al. created a laboratory-based human mouth model capable of measuring forces and moments acting on teeth with multibanded orthodontic fixed appliances. They simulated a high canine situation and using a 0.018″ CuNiTi he found the passive self-ligation method produced a more accurate force system for this malocclusion, with fewer unwanted forces and moments compared with elastic conventional ligation [8].
Nonetheless, although evident advances have certainly been made, not only in the use of brackets, but also in the mechanics and type of wires and accessories employed 9, 10, the most recent systematic review of the literature on this topic stated despite claims regarding the clinical superiority of self-ligating brackets, evidence is generally lacking [2].
Thus, the aim of this study was to show, by means of four clinical case reports, that conventional brackets, used in conjunction with relatively recently introduced thermal nickel-titanium archwires of reduced diameter and extremely light nickel-titanium springs, provide results comparable with those achieved via the use of self-ligating brackets.
Section snippets
Diagnosis
Skeletal Class I malocclusion in short face patient (22 years old) of normal profile (fig. 1). Intra-oral clinical examination showed dental Class I on the left side and a head-to-head relationship on the right. Slight crowding was present in the anterior sector of the lower arch. The upper dental median line was severely displaced towards the right with respect to the facial and lower dental medians. The right upper canine was ectopic and located far above the occlusal plane (fig. 2).
Diagnosis
Skeletal Class I and dental Class II (head-to-head) in a normodivergent patient (15 years old) (fig. 13). No crowding was present in the lower jaw, although the upper right first premolar was rotated more than 60° in a mesial direction. The upper right canine, despite a lack of rotation, showed considerable labial and distal displacement. Both median lines were deviated; in particular the upper median showed a deviation towards the right (fig. 14).
Extraoral examination revealed poor exposure of
Diagnosis
Skeletal Class III malocclusion in a long face patient (18 years old) with maxillary retrusion and mandibular protrusion. Facial photographs showed maxillary and mandibular asymmetry (fig. 25). Intra-oral clinical examination showed dental Class I on the left side and a head-to-head relationship (Class II) on the right. Slight crowding was present in the anterior sector of the lower arch, while the upper arch was constricted and there is no space for upper right canine. The upper dental median
Diagnosis
Skeletal Class III malocclusion in a young male patient (11,8 years old) with maxillary retrusion (fig. 38). The patient showed a mixed dentition and a bilateral Class III molar malocclusion. There is a lateral and anterior cross bite. Upper right canine was ectopic erupted near the upper central right incisor while left upper canine was only partially erupted (fig. 39). Upper dental midline seems to be shifted toward the left side. Intra-oral occlusal photos showed the amount of the crowding
Discussion and conclusion
Numerous authors have stated that the main advantages of self-ligating brackets are: creation of alveolar bone, less proinclination of the incisors, less need for extraction [9], more efficient sliding mechanics [7], reduced treatment times, reduced chair-side times [11], better infection control [12], less patient discomfort [13] and better oral hygiene 12, 14.
Nevertheless, Stephanie Shih-Hsuan Chen et al. [2], in their systematic review, concluded that scientific evidence proving the clinical
Disclosure of interest
The author declares that he has no conflicts of interest concerning this article.
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