Beckwith FR, Ackerman RJ, Cobb CM, Tira DE An evaluation of factors affecting duration of orthodontic treatment. Am J Orthod Dentofacial Orthop. 1999; 115:439-447
Creekmore TD The importance of inter-bracket width in orthodontic tooth movement. J Clin Orthod. 1976; 10:530-534
Synchronous Straight-Wire (SSW) is the trademark of the authors Charles Cole and Jon Hammond. This paper is split into two parts. Part one introduces the SSW technique, explains the reasons for its development and outlines theory. Part two illustrates the technique and compares it to others. The aim of this paper is to introduce the SSW technique, which is designed to produce simultaneous synchronized movement and thereby improve efficiency. Complex concurrent movements require planning and co-ordination. An Appliance Configuration Table (ACT) facilitates this and enables the clinician to plan the required movements to correct tooth position fully before linking these to required forces for resolution. Forty cases treated using SSW are compared with other techniques. Efficiency of tooth movement is monitored using a treatment efficiency index (TEI). When compared with other techniques, SSW demonstrates improved efficiency. The technique offers a more efficient means of undertaking fixed appliance treatments and highlights the advantages of pre-programming the entire appliance (not just the brackets) and of using a coherent mechanism to facilitate 3-dimensional movements.
Clinical Relevance: The Synchronous Straight-Wire (SSW) technique is a means of organizing simultaneous treatment events by synchronizing, rather than sequencing, tooth movement.
Article
There is a clear disparity between physiologically possible rates of tooth movement and mechanically achieved treatment times. If teeth can be moved at rates of 1mm per month, and in most malocclusions the maximum displacement/movement required for any individual tooth is less than 8 mm, then why do we routinely experience treatment times in excess of 24 months?1
Such inefficiency may result from:
SSW improves efficiency with a radically alternative approach and abandons ‘traditional’ staging. This is made possible by the form of the mini-uni-twin bracket and 0.017″ × 0.025″ thermal archwire combination. The increased inter-bracket distance created by this bracket reduces the level of force generated by any archwire engaged by a factor of 3.5.2 This principle enables a 0.017″ × 0.025″ thermal wire to be fitted whilst still delivering physiological forces at the outset of treatment. Wires with this cross-section not only have sufficient stored energy to bypass misaligned teeth, thereby increasing inter-bracket span considerably, but also facilitate the early use of auxiliaries (inter-maxillary elastics, coil spring, etc) to control tooth movement in three dimensions. This radically alters the clinician's ability to unravel a malocclusion from the outset. The essence of the technique is to retain flexibility and fluidity in order to optimize progress until all major events have occurred and to synchronize movement rather than sequence it. There is no reason why treatment events cannot be undertaken simultaneously, reducing treatment times and numbers of visits. However, multiple concurrent movements require synchronization to avoid chaos, thus the concept of Synchronous Straight–Wire, which aims to match physiologically possible rates of movement with theoretically achievable treatment times. Treatment efficiency is measured using the treatment efficiency index (TEI).
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