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Ortho - international magazine of orthodontics No.1, 2017

clear aligners trends & applications | Fig. 6a Fig. 6b Fig. 7a Fig. 7b Fig. 8 Fig. 9a Fig. 9b Fig. 10 Figs. 6a & b: Areas of gingival impingement or irritation from clear aligners can be cleared using the HOLE PUNCH to remove plastic. – Figs. 7a & b: The VERTICAL instrument produces a shallow indent in the plastic to accent rotational couples on individual teeth. – Fig. 8: The indents from either the VERTICAL or the HORIZONTAL pliers may be formed immediately adjacent to attachments to accent the contact point of plastic in the right angle between composite and tooth, with the intention of increasing the effectiveness of the attachment. – Figs. 9a & b: Adding root torque to specific teeth is enhanced by creating indents with the Horizontal pliers. The same tool may also be used to increase the retention of aligners or clear retainers. – Fig. 10: Aligner lag or loss of tracking is a common occurrence, especially for maxillary lateral incisors, the least predictable tooth movement. The air gap is a symptom of ill-fitting aligners and may have a number of causes (e. g. poor compliance, insufficient space created for the tooth to follow and lack of surface area contact with plastic). Clear Collection The HOLE PUNCH As understanding of some of the limitations of clear aligner applications came to light, alterations to biomechanics, materials and treatment planning were introduced. The primary aims were to improve the predictability of specific tooth movements and to expand the scope of treatment to a wider variety of presenting malocclusions. A set of instruments were created specifically for clear aligners in order to enhance, accent and increase the spectrum of appli cability and acceptability of this form of aesthetic orthodontic treatment. The Clear Collection consists of four instruments designed to individualise aligners to address specific treatment needs.23–24 The TEAR DROP The TEAR DROP instrument is used to add a notch or hook in the gingival margin of aligner plastic for the application of typical orthodontic elastics.19–21, 23 The design of this cut-out is in the shape of a teardrop with the intent that the reservoir of the notch will keep an elastic in place on the aligner (Figs. 2a–c). In this manner, the aligner with elastics can be inserted into the mouth, reducing the fumbling and difficulty associated with attempting to put elastics into slits or notches after the aligner tray is already on the teeth. The TEAR DROP cuts can be made anywhere along the aligner tray edges where elastics may be needed, such as inter- maxillary Class II, Class III or delta, or Class I intra-maxillary applications, even involving the use of mini-screw anchors to support the elastic forces (Fig. 3).19, 21, 23 The HOLE PUNCH instrument is used to create a half- moon cut-out at the gingival margin of aligner plastic (Figs. 4a & b).19–21, 23 The intention is to relieve the plastic to permit the application of bonded buttons or brackets on specific teeth to support orthodontic elastics or chains. These cuts can be placed wherever needed along the aligners on either buccal or lingual surfaces. A com- mon scenario would be punching holes in the buccal margin of plastic at the maxillary and mandibular first molars and canines to bond buttons to support seating or box elastics (Fig. 5)23 or cutting a half-moon on both the lingual surface of the maxillary first molar and buc- cal surface of the mandibular first molar to facilitate the use of a through-the-bite cross-bite elastic. In addition, the HOLE PUNCH may be employed to simply clear plastic away from impinging gingival tissue anywhere along the aligners.23 The incisive pa- pilla is a common location for this type of irritation that can be quickly resolved by clipping the plastic in that area for each tray in a series (Figs. 6a & b). Individualising aligners with accent pliers Two accent pliers round out the Clear Collection. These unique instruments were designed to enhance specific types of tooth movement by increasing plastic contact points in precise locations for individ- ual teeth. The intent is to increase the predictability of tooth movements by creating shallow indents in the plastic to augment prescribed mechanical couples. Most importantly, these pliers are not heated. In addition, these indents may be produced to increase the retentiveness of aligners or clear retainers in undercuts and at line angles. ortho 1 2017 17

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