ortho the international C.E. magazine of orthodontics

I 15ortho3_2012 C.E. article_ Bent Wire System I ThesimplenatureoftheBWSmakesitpossibletoas- semble in-house, avoiding the fees that accompany laboratory-constructed appliances. An advantage of this system is that it does not involveusingacrylicinthepalatalvault.Afunctional appliance designed with acrylic on the palate and that is not properly built may lower the tongue, encouraging tongue thrusting and, thus, either worsening the malocclusion or producing a relapse (Fig. 3). The Trainer is a prefabricated functional ap- pliance, which means no laboratory involvement, and the BWS can be entirely constructed “in office”. TheBWSisnotmadeofacrylic,nordoesitoccupythe palate. It allows the tongue to position correctly and the patient to speak normally. The BWS is also suitable for use in the lower arch. Typical treatment tends to use only upper expansion for three to four months, after which time the wire component of the BWS is removed (the bands are kept for later use of the BWS). The i-2 Trainer (with theinner-cagethatproducesarchexpansion)isthen used to maintain the initial arch expansion gained using the BWS. Lower alignment is re-evaluated throughoutthisstageofi-2Traineruse.Often,ascan be demonstrated in the cases selected, lower align- ment and arch form improves because of the maxil- lary expansion and peri-oral musculature functional improvement (Figs. 4a, 4b). The BWS is held in place using standard ligatures placed around the BWS tube as pictured (Fig. 5). The following two cases show the effect of the BWS Orthodontic System on arch development. _Case No. 1 This 10-year-old female patient consulted be- cause of a crowded dentition involving unusually misaligneduppercentralincisorswithamidlineshift of 10 mm and with lost “c” space on the lower left side. The parents requested that the treatment be non-extraction, although they had previously been advised that future orthodontic treatment might require this option (Figs. 6a–6d). The occlusion was classified as Class I with normal slight overjet and with normal overbite. No skeletal alteration was foundoncephalometricmeasurements,andanalysis of cast models reported a lack of arch development. This case was diagnosed as a Class I malocclusion with underdevelopment of both dental arches. Mid- lineshiftwasprimarilyasaresultofthelostlower“c” Fig. 6c Fig. 6d Fig. 6a Fig. 6b