CHAPTER 5 Treatment stages
Differential tooth movement, as previously defined, involves repositioning of the crowns of the teeth first, followed by root uprighting to the new crown positions. However, there is a prescribed overall sequence of tooth movements, in the correction of any malocclusion with Tip-Edge, that needs to be followed closely. It is basically very simple and goes as follows:
• Stage I is all about the anterior segments, which should be aligned, and any incisor spacing closed. They should also be corrected both antero-posteriorly and vertically (eliminating overjets, reverse overjets, increased overbites or anterior open bites). The archwires most commonly used will be .016 inch high tensile stainless steel, the resilience and flexibility of which is ideal for overbite reduction. Nickel–titanium auxiliary ‘under arches’ are frequently employed in the initial treatment visit, to assist in the alignment of instanding or rotated teeth. However, it should be noted that an ‘under arch’ runs beneath the main archwire, in the bracket slot, and never through the deep tunnels. Use of the deep tunnels in Plus is intended for Stage III only.
• Stage II concerns closure of any residual extraction spaces and seldom exceeds 3 or 4 months, except perhaps in first molar extraction cases. In non-extraction cases, it will obviously be very brief. However, it is important that centrelines should be coincident and correct before all the spaces are closed, since centreline discrepancies will prevent the attainment of a correct Class I occlusion. Also, towards the end of the stage, the first molars will require to be derotated in readiness to receive the rectangular archwires of the third stage.
• Stage III is the root uprighting phase, during which each tooth is torqued and tipped to its preadjusted values to complete the treatment. Previously, and with the Rx-1 bracket, this was achieved by the action of Side-Winder springs working against rectangular .0215 × .028 inch stainless archwires. The Plus bracket will use a deep tunnel nickel–titanium auxiliary archwire to do the same. The rectangular archwires will be identical />
Stay updated, free dental videos. Join our Telegram channel
VIDEdental - Online dental courses
