Minimally-Invasive Tooth Extraction: Doorknobs and Strings Revisited!

Transcription

1 Dniel Sund Thoms Dietrich Minimlly-Invsive Tooth Extrction: Doorknos nd Strings Revisited! Astrct: References to trumtic tooth extrction pervde the recent dentl literture. This hs een lrgely driven y the incresing demnd for one preservtion s osseo-integrted implnts incresingly ecome minsty for dentl prosthetic rehilittion. This rticle introduces the reder to the concept of verticl tooth removl, which ims to void socket expnsion nd therey minimize trum to lveolr one during tooth extrction. Severl systems hve recently ecome ville nd we present our experience with the Benex extrctor in prticulr. Clinicl Relevnce: Clinicins should e wre of minimlly invsive extrction techniques, their indictions nd potentil dvntges. Dent Updte 2013; 40: Legend hs it tht, in dys gone y, the prctice of hving tooth pulled y one end of string eing tied to the tooth nd the other to doorkno, nd then slmming the door closed, ws not such n uncommon prctice. We re plesed to sy tht, s profession, we hve long moved on from such crude nd unrefined pproches to tooth extrction. Since the puliction of Ky nd Killey s rticle in the inugurl issue of this journl, 1 extrction techniques hve evolved y revisiting the principle of tooth pulling (s ws the cse with the forementioned home remedy), leit with slightly more finesse nd technicl ingenuity, thnks to severl extrction systems tht hve ecome ville over the pst decde. The sic principle of this technique is to extrct the tooth exclusively y pulling long its long xis (verticl Dniel Sund, BDS, MFGDP, MFDS RCPS, MJDF RCS, M.ORAL.SURG nd Thoms Dietrich, Dr med, Dr med dent, MPH, FDS RCS, Deprtment of Orl Surgery, Birminghm Community Helthcre NHS Trust, The School of Dentistry, University of Birminghm, St Chd s Queenswy, Birminghm B4 6NN, UK. extrction). We will discuss the rtionle for this technique nd provide detiled description of our experience with one of the ville systems. Doorknos nd strings side, the ide of verticlly extrcting tooth is not new, nd specil forceps hd een ville in the ltter hlf of the eighteenth century to chieve this. 2 The forceps were dvertised in the Mercure de Frnce, French mgzine for elegnt society discussing intellectul detes of the time. The dvertisement climed tht the new instrument cuses less tering nd consequently less pin thn ordinry instruments when tooth extrction ws necessry. The dvert went on to suggest tht the instrument ws not only useful for surgeon-dentists, ut lso to those who hve the courge to operte on themselves! 2 Apprently, these instruments fell out of fvour minly ecuse they relied on the presence of neighouring teeth to the one to e extrcted nd hd complex construction, mening tht they were difficult nd time consuming to use. In ddition, multi-rooted teeth could not e removed verticlly. 2 Interestingly, some of these limittions still hve to e considered with the currently ville systems. The development of these novel systems hs undoutedly een driven y the desire to preserve s much one s possile in the context of implnt therpy, nd references to trumtic extrctions now pervde the literture. Although the term trumtic extrction hs never een clerly defined, it is cler tht, with the possile exception of orthodontic extrusion, no extrction technique cn e completely trumtic. We therefore feel tht the term minimllyinvsive, which is lso used in other res of surgery, would e more pproprite. The mount of trum sustined y the periodontl tissues vries considerly in current prctice, rnging from the reflection of mucoperiostel flp nd surgicl removl of one to retrieve roots, to n uncomplicted extrction of singlerooted tooth using forceps, luxtors nd/or periotomes. Bony trum is difficult to void s the very principle of forceps extrction is socket expnsion (Figure 1) nd even successful extrction using luxtors or periotomes will trumtize lveolr one to some extent, s ny movement in horizontl direction or rottion, unless it is perfectly circulr root, will t minimum result in some one expnsion. However, t lest conceptully, there is no direct trum to the socket wlls when severnce of the periodontl ligment is chieved y pulling conicl root in n xil direction from My 2013 DentlUpdte 325

2 its socket in controlled nd mesured mnner (Figure 2). This is the centrl tenet of the verticl extrction systems ville tody, which re ll inspired y well-estlished kitchen tool (Figure 3). Given the plethor of different corkscrew devices in people s kitchens, it will not surprise the reder tht more thn one system for verticl extrction hs ecome ville over the pst decde. To our knowledge, these include the following three systems: Benex; Esy X-TRAC; Apex Control. The common feture of these systems is the use of screw tht is plced in the root of the tooth to e extrcted nd mechnism is then pplied tht llows the Figure 1. Conventionl extrction processes utilize horizontlly directed forces for tooth removl (tken from Hupp JR. Principles of uncomplicted exodonti. In: Contemporry Orl nd Mxillofcil Surgery 5th edn. Hupp JR, Ellis III E, Tucker MR (eds). St Louis: Mosy Elsevier, 2008: p117, used with permission). extrction force to e trnsmitted to this screw. The currently ville systems differ in the specifics of this ltter mechnism. We descrie here our extensive experience with one of the ville systems (Benex extrctor, Hger & Meisinger GmH, Neuss, Germny nd Helmut Zepf Medizintechnik, GmH, Tuttlingen, Germny) which, in our opinion, hs severl distinct dvntges in terms of its flexiility. It should e mde cler from the strt tht ecuse of the extrction principle, the use of ny verticl extrction system is limited to single-rooted teeth or multi-rooted teeth with non-divergent roots. However, divergent roots cn of course e sectioned nd pproched seprtely in some cses. The Benex extrctor Benex extrction the sics of the procedure The sic Benex system consists of the Benex extrctor itself (Figure 4), set of dimond urs (1.6 nd 1.8 mm), set of self-tpping screws, pullstring nd sectionl impression try (Figure 4). The following cse demonstrtes how the Benex extrctor cn e used to remove crious upper second premolr. It cn e seen from the rdiogrph (Figure 5) tht miniml coronl tissue remins which would necessitte extensive use of luxtion, or trnslveolr surgicl procedure. It is possile to remove this lrge retined root with the Benex system nd this is demonstrted. The first step in the extrction procedure is the preprtion of screw-hole in the centre of the tooth using dimond ur (1.6 mm or 1.8 mm dimeter), commonly (ut not necessrily) following the course of the centrlly locted pulp cnl. Removl of crious tissue is optionl, ut my e indicted to provide etter overview (Figure 5 d). A self-tpping nchor screw is then inserted until firmly secured into the root (Figure 5e). The force required to remove the root will e counterlnced ginst the djcent teeth or edentulous ridge, depending on the clinicl scenrio. In this cse, the Benex extrctor is stilized directly y the djcent teeth (Figure 5f). To chieve proper plcement nd support for the Benex extrctor, it my e necessry to position the sectionl impression try using some silicone impression mteril to stilize its loction. The pullstring is then locted within the hed of the nchor screw. The T-r t the other end of the pullstring is positioned into one of three notches on the Benex extrctor (Figure 5f). Grdul force is pplied to the tooth root y turning the kno t the end of the extrctor clockwise, which results in controlled severnce of the periodontl ligment nd emergence of the retined root from its lveolus (Figure 5g, h, i). Figure 2. Verticl extrction genertes force in coronl direction only. Figure 3. Well estlished instrument tht is used for verticl extrction of corks from ottles with predictly high success rtes! The sme principle is used with verticl tooth extrction. Figure 4. () Benex extrctor ( T Dietrich, used with permission). () Benex system components ( T 326 DentlUpdte My 2013

3 c d e f g h i Figure 5. () Lrge crious retined upper premolr root ( T (, c) Removl of crious tooth tissue prior to extrction ( T (d) Preprtion of screw hole ( T (e) Self-tpping nchor screw in plce ( T Dietrich, used with permission). (f) Shows Benex extrctor resting directly on to djcent teeth with pullstring locted into screw nd the T-r locted into the second notch ( T (g, h, i) Shows root emergence from its socket following grdul xil pressure from the Benex extrctor ( T Benex extrction how well does it work? At Birminghm Dentl Hospitl we hve een using the Benex system for extrctions of teeth deemed unsuitle for forceps extrction, nd we hve performed n oservtionl study in order to document the success rte of this technique nd its limittions. The results of the extrction of the first 111 roots in 72 ptients hve recently een pulished. 3 Overll, 83% of teeth were successfully extrcted, with the success rte eing higher in single-rooted teeth (89%) when compred to multi-rooted teeth (43%). It is importnt to note tht the study ws limited to teeth not suitle for forceps extrction, did not include mxillry molrs or mndiulr third molrs nd did not include teeth with incresed tooth moility. Perhps the most exciting finding ws tht, overll, only 7% of teeth required surgicl removl (flp reflection nd/or one removl following filure to extrct the tooth with the Benex system), lthough the surgeons estimted tht 44% of teeth would hve required surgicl pproch hd the Benex system not een used. This suggests tht significnt proportion of teeth tht would otherwise require surgicl pproch cn e successfully 328 DentlUpdte My 2013

4 extrcted with the Benex system. Filure to complete n extrction with the Benex system in our experience cn usully e ttriuted to one of two min resons. Firstly, the root morphology my not e comptile with verticl extrction (Figure 6), which is often impossile to scertin from stndrd rdiogrph. Secondly, filure my occur s result of insufficient retention of the screw nd/or the root frctures. This cn either e due to cries or filure to plce the screw in n idel position into the centre of the root. In our experience, this ws prticulr prolem with slender roots, such s mesil roots of lower molrs (Figure 7). Benex extrction tips nd tricks try is necessry to provide stle support Alignment of the pullstring for the extrctor in cses where djcent In order to chieve n optiml teeth on either or oth sides of the tooth force vector for tooth extrction nd to to e extrcted re missing (Figure 9). void complictions such s screw ending, However, it will often lso provide more the pullstring should e perfectly ligned stle support when djcent teeth re with the screw. This is esy to chieve with present, in prticulr with extrctions in the the Benex system s the trnsmission wheel nterior region. Secondly, the impression offers some flexiility to move the extrctor try distriutes the counterforce evenly mesilly or distlly in order to chieve cross lrger re nd it is therefore optiml lignment. If this is insufficient, the prticulrly suited for situtions in impression try should e used in order to which lrge forces re to e voided chieve lignment, even if neighouring (eg restortions, cntilevers). Thirdly, teeth re present (Figure 8). Alterntively, the impression try my e necessry n ngled support disc hs recently een to chieve optiml verticl lignment of developed to fcilitte chieving the correct the pullstring (Figure 9, c). For ll these lignment of the pullstring with or without the id of the impression try (Figure 8). In our opinion this is distinct dvntge of the Benex system over the other two currently ville systems, where verticl lignment of the force vector is not so esily chieved. Use of the impression try The impression try hs severl importnt functions. Firstly, the impression Figure 6. Irregulr root morphology locking tooth into its socket mking verticl tooth extrction improle ( T Dietrich, used with permission). c Figure 7. (, ) Nrrow root morphology cn led to filure of retention of screw into root ( T Figure 8. () Inpproprite lignment of the pullstring despite the presence of neighouring teeth. This cn e corrected with the use of the impression try nd/or ngled support disc. () Use of impression try nd ngled support disc to chieve optiml positioning of the device ( T Figure 9. ( c) Use of the impression try to support the Benex extrctor when the retined root is djcent to n edentulous re. The try is used to good effect to ensure tht the pullstring remins in xil lignment with the retined root ( T My 2013 DentlUpdte 329

5 resons, use of the impression try is often necessry or dvisle; in our study it ws used in 3 out of 4 cses. 3 Upper premolrs Upper premolrs constitute prticulr chllenge s they re often multi-rooted, nd the exct root morphology, ie whether or not the roots re divergent, cnnot e scertined from stndrd rdiogrphs preopertively. Bsed on our experience, we therefore recommend to plce the screw initilly in the centre of the root. If the tooth is single-rooted or multirooted with non-divergent roots, this will typiclly result in successful extrction of the tooth, even if some perfortion of the furction my hve occurred (Figure 10). In cses of divergent roots, the tooth is unlikely to yield, nd the roots cn then e sectioned y extending the hole in mesiodistl direction. The roots cn then e pproched seprtely. Luxtion of tooth In contrst to the mnufcturer s instructions, we do not recommend ny luxtion of the tooth to e extrcted s this would contrdict the minimlly invsive principle of the verticl extrction. However, if the tooth does not yield to sustined input of significnt extrction force, luxtion of the tooth cn e ttempted while the extrction force is eing pplied (Figure 11). In our study, luxtion ws performed in only 5% of successfully extrcted teeth, some of which hd een luxted s prt of previously filed routine forceps extrction. In conclusion, the vst mjority of successful Benex extrctions cn e chieved without luxtion. Indictions nd contr-indictions In theory, minimlly invsive verticl extrction methods my hve severl enefits compred to conventionl extrctions using luxtors nd/or forceps, which re listed in Tle 1. However, it is importnt to note tht, t present, none of these enefits hs een scientificlly vlidted in roust mnner. Figure 10. Benex screw plced centrlly etween the two roots in n upper first premolr ( T Figure 11. Concurrent use of luxtor (if needed) is not hindered y the Benex system, unlike other verticl tooth extrction systems ( T While some of the dvntges of the verticl extrction method, such s voidnce of flp surgery, re most ovious for root remnnts not suitle for forceps extrction, the use of the system is y no mens limited to such cses. Teeth do not necessrily hve to e decoronted prior to removl, s it is possile to extrct complete teeth y plcing the screw into coronl enmel nd dentine (Figure 12). Contr-indictions to use of the system re multi-rooted teeth with divergent roots tht cnnot e sectioned nd clinicl situtions in which the extrctor cnnot e ppropritely pplied owing to limited ccess. Conclusion Perhps our forefthers with their doorknos nd strings were on to something fter ll. It just took us hundred yers to finlly relize! Bsed on our experience, we recommend the Benex system for extrction of incisors, cnines nd premolrs. In selected cses, it my lso e useful for extrction of molr roots, in prticulr the distl roots of mndiulr Figure 12. Successful use of the Benex extrctor to remove complete cnine without the need to decoronte the tooth ( T Dietrich, used with permission). Reduced post-extrction one resorption nd preservtion of residul lveolr height nd width Reduced trum to lveolr one nd soft tissues in high-risk ptients (eg ptients on isphosphonte mediction, ptients post-rdiotherpy) to reduce incidence of complictions Reduction in flp surgery Improved ptient stisfction, clinicl procedure more cceptle to the nxious dentl ptient Reduced post-opertive moridity Less risk to ntomicl structures mentl nerve, mxillry sinus Improved post-opertive soft tissue esthetics Improved success of intentionl reimplnttion/utotrnsplnttion due to minimized trum to periodontl tissues Tle 1. Potentil dvntges of minimlly invsive extrctions. molrs nd the pltl roots of mxillry molrs. It my lso e used for extrction of impcted teeth in selected cses, in the context of surgicl extrction to minimize one removl. References 1. Ky LW, Killey HC. The extrction of teeth: pre-opertive ssessment. Dent Updte 1973; 1: Riches S. Verticl-extrction forceps. BDA News 2012; 4: Musk E, Wlter C, Knight A et l. Atrumtic verticl tooth extrction: proof of principle clinicl study of novel system. Orl Surg Orl Med Orl Pthol Orl Rdiol 2012; Jul 3 [Epu hed of print]. 330 DentlUpdte My 2013