2018 JCO, Inc. My not e distriuted without permission. www.jco-online.com Resin Bite Turos NEAL KRAVITZ, DMD, MS GREG JORGENSEN, DMD, MS SCOTT FREY, DDS, MSD JASON COPE, DDS, PhD Resin ite turos, sometimes referred to s uild-ups, re creted y onding composite mteril to the pltl or occlusl surfces of teeth. Their primry purpose is to prevent hevy contct of the upper teeth with lower fixed pplinces in ptients with deep overites, ut they cn lso e eneficil in cses involving crossites or hyperfunctionl mstictory muscles. Although the ppliction of resin turos is well-known technique, there re differences of opinion out where to plce them nd wht mterils to use. This review is intended to improve the clinicin s understnding of the rtionle for such choices. The utiliztion of functionl turos will lso e discussed. Development of Bite Turos Orthodontists hve historiclly corrected deep overites with removle nd fixed upper nterior crylic ite pltes. These pplinces disrticulte the posterior teeth; deprogrm the mstictory muscles; nd llow for eruption, extrusion, nd uprighting of the posterior teeth. 1 Removle ite pltes require ptient complince, however, s well s frequent djustments to ccount for orthodontic tooth movements. Bnded ite pltes provide fixed lterntive, ut they re less ccommodting of tooth movements nd cn cuse soft-tissue irrittion. In 1994, Joe Myes of Ormco Corportion creted metl ite turo s n lterntive to the crylic ite plte. 2 Myes s design ws simple modifiction of lingul upper incisor rcket. After one to four turos were onded to the pltl surfces of the upper incisors, the lower incisors occluded on the turos 44 occlusl ledges to prop open the ite. Myes elieved metl ws etter mteril for deprogrmming the muscles thn the softer crylic used in conventionl ite pltes. Metl turos lrgely replced ite pltes ecuse of their durility, ese of hygiene, nd simplicity, ut they were not without prolems. Most notly, metl turos were sometimes difficult to plce ecuse of the vriility of the upper incisors lingul ntomy. Posterior metl turos consisted of stinless steel crowns plced over otherwise norml molrs. Common side effects of metl turos included lisping nd intolerle tooth virtions. These issues prompted the cretion of resin lterntive for use in overite correction. Overite Correction A ptient with retrognthi or reduced lower rch perimeter is prone to the development of deep overite nd steep curve of Spee (Fig. 1). The lower incisors erupt until they contct the opposing teeth or pltl soft tissue, forming the nterior component of the curve of Spee. The lower 456 2018 JCO, Inc. JCO/septemer 2018
Dr. Krvitz Dr. Jorgensen Dr. Frey Dr. Cope Dr. Krvitz is n Associte Editor of the Journl of Clinicl Orthodontics nd in the privte prctice of orthodontics t 25055 Riding Plz, Suite 110, South Riding, VA; e-mil: nelkrvitz@gmil.com. Dr. Jorgensen is in the privte prctice of orthodontics in Rio Rncho, NM. Dr. Frey is in the privte prctice of orthodontics in Chespeke, VA. Dr. Cope is n Adjunct Assistnt Professor, Deprtment of Orthodontics, College of Dentistry, Texs A&M University, Dlls, nd in the privte prctice of orthodontics in Dlls. ptients, the lower second molrs should e onded s erly s possile. Light, verticl posterior elstics (2oz) cn e prescried to ssist in premolr extrusion. In ptient with hyperfunctionl mstictory muscles, s is commonly seen in low-ngle cses, Botox* cn e used in conjunction with ite turos to fcilitte posterior extrusion. 3 The posterior teeth re discluded y the resin turos on the upper centrl incisors. Fig. 1 Steep curve of Spee commonly seen in retrognthic, low-ngle ptients. Lower second molrs erupt distl to upper first molrs nd prior to upper second molrs, cusing supreruption. Bonding lower second molrs is criticl ecuse they ssist in extruding premolrs nd first molrs for overite correction. second molrs then erupt distl to the upper first molrs nd re unopposed until they contct the upper second molrs, mking up the posterior component. Overite correction requires reversl of this process to level the curve of Spee. Specificlly, the premolrs nd first molrs re extruded, while the incisors, cnines, nd second molrs re intruded. Complete leveling of the curve of Spee is difficult without onding the lower second molrs, ecuse their inclusion provides lever rm for extrusion of the lower posterior teeth. 1 Becuse posterior extrusion nd overite correction cn e prticulrly chllenging in low-ngle Turo Loctions The mndiulr plne ngle is lwys n importnt fctor in choosing turo loctions. Anterior resin turos re indicted in low-ngle ptients, while posterior resin turos re etter suited for verge-ngle cses. 1 Anterior turos should e used with cution in high-ngle cses ecuse of the risk of undesirle posterior extrusion; insted, only the upper teeth should e rcketed until the overite hs een reduced enough for the lower teeth to e onded. The most common loctions for nterior resin turos re on the lingul spect of the upper centrl incisors (Fig. 2). Both centrl incisors re customrily onded to rodly distriute the occlusl forces. Upper lterl incisors re rrely used ecuse of their shorter roots, lthough this could e n lterntive loction if the ptient develops lisp. Posterior resin turos re usully plced on the supporting cusps of the lower first molrs (Fig. *Registered trdemrk of Allergn USA, Mdison, NJ; www.otox. com. VOLUME LII NUMBER 9 457
RESIN BITE TURBOS 3). In predolescent ptient, the lower second deciduous molrs re nother possiility. Some prctitioners prefer plcing turos on the upper premolrs nd first molrs for esier isoltion during onding. On the whole, however, posterior turos re less effective in providing clernce for lower nterior rckets nd my require excessive thickness in low-ngle ptients. Mteril Choices Mny mterils hve een proposed for resin turos, including crylic gels, nd cements, rcket dhesives, nd lingul retiner dhesives. Ech hs dvntges nd disdvntges relted to its color, plcement nd removl techniques, nd glss filler content (Tle 1). Glss fillers such s qurtz nd silic re included in dentl resins primrily to dd hrdness; they lso help minimize polymeriztion shrinkge nd improve hndling chrcteristics. In orthodontic resins, fillers reduce the incidence of rcket deonding due to cohesive filure nd of mteril wshout under nds, nd they dd ody to control rcket flottion. On the other hnd, the use of turo mteril with high filler content increses the risk of rsion on opposing teeth. Qurtz is of prticulr concern ecuse it is hrder nd more Fig. 2 A. Upper nterior turos on oth centrl incisors. B. Dome-shped turos covering most of cingule improve tolernce nd pply intrusive forces to upper nd lower incisors. Fig. 3 A. Lower posterior turos on first molrs. B. Tue-shped lower first-molr turos plced long supporting cusps. Archwire helps pply intrusive forces to lower second molrs nd extrusive forces to premolrs nd first molrs. Resin cn e extended over rcket pd for dded rcket retention. 458 JCO/septemer 2018
KRAVITZ, JORGENSEN, FREY, COPE TABLE 1 POPULAR MATERIAL CHOICES Product Originl Purposes Type Advntges Disdvntges Trid Gel** Bite pltes, cst modifiction Acrylic gel Soft, light color Polymeriztion shrinkge, hyperemi Ultr Bnd-Lok*** Bnd cement Compomer pste Bonds to metl, distinct color TruLock Light Cure Bnd Adhesive Ketc Bnd cement Compomer pste Bonds to metl, distinct color, fluoride relesing Bnd cement, permnent restortions Glss ionomer cement Moisture insensitive, fluoride relesing Csts lue shde Csts lue shde Difficult to remove Blugloo, Grengloo Brcket dhesive Resin pste Color chnge Potentil for wer Trnsond LR Flow Tin Lingul retiner dhesive Lingul retiner dhesive Resin pste Bond strength Potentil for wer Flowle resin Esy ppliction Potentil for wer Twinky Str Peditric restortions Compomer pste Esy ppliction, distinct color Potentil for wer rsive thn silic. Acrylic gels nd nd cements, which hve lower qurtz contents, re therefore most commonly used to mke resin turos. Trid Gel** is n crylic resin liquid designed for fricting ite pltes nd modifying dentl csts (Fig. 4). Its composition is primrily methcrylte mixed with silic glss (1-10% y weight). Becuse its formul is similr to tht of n crylic ite plte, it crries little risk of tooth rsion. The smll tues of resin re ville in four colors: cler colorless, cler pink, cler lue, nd cler red. These light colors re cceptle to ptients ut visile enough to id plcement nd removl y the orthodontist. After the teeth re etched nd primed, Trid Gel cn e pplied with microrush or repurposed dhesive syringe Fig. 4 Tue of Trid Gel** nd push syringe of Ultr Bnd-Lok.*** **Registered trdemrk of Dentsply Siron, York, PA; www.dentsply siron.com. ***Registered trdemrk of Relince Orthodontics, Inc., Itsc, IL; www.relinceorthodontics.com. Registered trdemrk of Rocky Mountin Orthodontics, Denver, CO; www.rmortho.com. Trdemrk of 3M Unitek, Monrovi, CA; www.3munitek.com. Trdemrk of Ormco Corportion, Ornge, CA; www.ormco.com. Trdemrk of Relince Orthodontics, Inc., Itsc, IL; www. relinceorthodontics.com. VOCO Americ, Inc., Indin Lnd, SC; www.voco.com/us. VOLUME LII NUMBER 9 459
RESIN BITE TURBOS Fig. 5 A. Appliction of Trid Gel using repurposed opque syringe with 18-guge Luer lock tip. B. Appliction of Ultr Bnd-Lok with microrush. Fig. 6 A. Functionl turo onded to lower incisors for correction of mild nterior crossite. B. Turo eveled lingully for proper contct with upper incisor. (Fig. 5). One disdvntge is tht the exothermic rection creted y light curing cn cuse hyperemi nd discomfort. This is often oserved when turos re plced on the upper incisors. The resin lso undergoes sustntil polymeriztion shrinkge, so the clinicin should verify the mrginl sel to void declcifiction under the turos. Ultr Bnd-Lok*** is compomer pste hyrid of dentl resin nd glss ionomer used for securing orthodontic nds nd lrge crylic pplinces (Fig. 4). Its composition includes glss filler (50-75% y weight), methcrylte, nd cid monomer. The product is pckged in push syringe; fter the teeth re etched nd primed, it cn e pplied with microrush or directly from the syringe tip (Fig. 5). Ultr Bnd-Lok hs the hndling properties of dentl resin nd the onding dvntges of glss ionomer. Its cid monomer llows it to ond chemiclly to metl lloys, which is prticulrly eneficil for turos plced on lower first molrs with uccl or occlusl mlgm restortions. Ultr Bnd-Lok s right lue color fcilittes plcement nd removl, ut cn lso cst drk shde through thin upper incisors. Most importnt, ecuse the glss filler contins some qurtz, the opposing teeth should e checked periodiclly for rsion, prticulrly if the mteril is used to construct functionl turos. Functionl Turos Beveled resin turos, lso referred to s functionl turos, re constructed with eveled occluding surfces tht guide the opposing teeth towrd the desired positions. Their most common ppliction is in the correction of mild nterior crossite (Fig. 6). Resin turo mteril is onded to the incisl edges of two or more lower incisors nd 460 JCO/septemer 2018
KRAVITZ, JORGENSEN, FREY, COPE Fig. 7 A. Functionl turos on first premolrs. B. Turos promote disrticultion to help correct Clss II mlocclusion. sme technique cn e pplied in Invislign ptients y dding unfilled rectngulr ttchments to the occlusl surfces of the ligners (Fig. 8). Fig. 8 Invislign functionl turos creted with unfilled occlusl ttchments (yellow) on first premolrs. then eveled lingully. Upon contcting the eveled surfce, the upper incisors re nudged forwrd nd the lower jw is directed posteriorly. 4 The dentl crossite will usully e corrected in out three months. Functionl turos cn lso e plced on premolrs to improve disrticultion in Clss II ptients (Fig. 7). These turos essentilly operte like onded Twin Block pplince: the mndile is disrticulted nd repositioned s the occluding premolrs slide long the eveled surfces. The Conclusion Resin ite turos re usully plced on the upper centrl incisors or the lower first molrs, depending on the mndiulr plne ngle. Although we hve suggested using n crylic gel or nd cement, mny other mterils re cceptle s long s the qurtz filler content is low enough or the durtion of use is short enough to void occlusl wer on the opposing teeth. REFERENCES 1. McLughlin, R.P.; Bennett, J.C.; nd Trevisi, H.J.: Systemized Orthodontic Tretment Mechnics, Mosy, St. Louis, 2001. 2. Myes, J.H.: Bite turos: New levels of ite-opening ccelertion, Clin. Impress. 6:15-17, 1997. 3. Frey, S.: The cse for soft-tissue orthodontics, Dentltown, 42-48, pulished online, Decemer 2015. 4. Jin, U.; Bhrti, C.; nd Chhjed, R.: A simplified method of correcting single-tooth crossite, J. Clin. Orthod. 50:437-438, 2016. ***Registered trdemrk of Relince Orthodontics, Inc., Itsc, IL; www.relinceorthodontics.com. Trdemrk of Protec Dentl Lortories Ltd., Vncouver, BC, Cnd; www.protecdentl.com. Registered trdemrk of Align Technology, Inc., Sn Jose, CA; www.ligntech.com. VOLUME LII NUMBER 9 461