Canine substitution Neal Kravitz

Join me for Neal Kravitz’s lecture on canine substitution and the clinical management of it. Focusing on bracket selection and canine recontouring Case selection · 2 key factors o Profile o Mandibular crowding Bracket selection · Goal: o Canine substitution: § Reduce canine root prominence o Premolar substitution: § Hide palatal cusp o Molar interdigitation: § class 2 cases 4 bracket choices for canine · UR1 (+17 tq, + 4 tip) · Achieves ideal torque · Requires flattening of canine labial face = plasty · UR2 (+10 tq, + 8 tip) o plasty and step out · UR3 inverted (+7tq, +8 tip) o Flipped U3 o Likely require addional torque · LL5 inverted (+17 tq, +2 tip) o Suggested by Marco Rosa o Same torque but no reduction labial face – compound contour Upper 1st premolar bracket selection · U3 or U4 slightly distal – palatal cusp hidden · See orthoinsummary blog on Premolar substitution Upper molar tube selection for class 2 finish · Achieve good interdigitation, the U6s tubes have 10 degree rotation labially, which does not interdigitate with the lower 5/6 embrasure space well, the 0 degree offset on lower 6s / 7s (-20 / -10 torque) · No change in tip and torque Tooth reshaping · Canine morphology frequently triangular, more so mesial then distal · Reduction – frequently underdone o Mesial IPR – Kailasam 2021 1.2mm enamel mesial o Incisal reduction o Palatal reduction Interproximal reduction for Bolton’s discrepancy Class 1 · Canine substitution with lower extractions = maxillary excess o = IPR uppers to correct Bolton’s discrepancy (U 1, 3, 4) Class 2 · Canine substitution, lower non-ext = Mandibular excess o = IPR lower anterior to correct Bolton excess (U 1, 3, 4) Cosmetic bonding · Step 1: Mesial step out o Improve marginal ridge with central o Reduce occlusal interference lower arch · Step 2: Mesial build up o Mesial incisal o Line angle not that I practice it but they are essentially § Transition between proximal and labial face § Can make canine look narrower through altering this transition, ie the shallower gradient narrower the tooth Retention and review · Group function and lateral clearance · Long term fixed retention 4-4 o Length of bonded retainer § Lower canine mid to distal lateral incisor labial measurement = lingual 3-3 measurement o Material – memotain Custom NiTi References Rosa, M.A.R.C.O. and Zachrisson, B.U., 2001. Integrating esthetic dentistry and space closure in patients with missing maxillary lateral incisors. Journal of Clinical Orthodontics, 35(4), pp.221-238 Kokich Jr, V.O. and Kinzer, G.A., 2005. Managing congenitally missing lateral incisors. Part I: Canine substitution. Journal of esthetic and restorative dentistry, 17(1), pp.5-10. Kravitz, N.D. and Shirck, J.M., 2017. Measuring Bonded Lingual Retainers. Journal of clinical orthodontics: JCO, 51(5), pp.294-294. Kravitz, N.D., Miller, S., Prakash, A. and Eapen, J.C., 2017. Canine bracket guide for substitution cases. J Clin Orthod, 51, pp.450-453.