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J Ind Orthod Soc 2005 ; 38:68-78 INTERVIEW Dr. Ravindra Nanda on his treatment philosophy Part - I International consultant Editor Dr. Ramesh Sabhlok interviews Dr. Ravindra Nanda on his treatment philosophy. Dr. Ravindra N and a is at present UConn A lumni Endowed Chair, and Professor and Head of the Department of Orthodontics, Ora l and M ax ill ofacia l Surgery, Pediatric Dentistry and Adva nced Education in Genera l Dentistry at the University of Connecticut, Farmington, Co nn ecti cut, U.S.A. Dr. N and a has been author and co-a uthor of three o rthodo nti c books and more than o ne hundred scie nti fic and clinical artic les in majo r jou rn als. H e is on the editorial board of severa l journals. He is an active member of various organ izations, including the American Association of Orthodontics, European Orthodontic Society and Edward H . Angle Society. Dr. Nanda is a Diplomate of the American Board of Orthodontics. Ramesh Sabhlok: On behalf of the Editor-In-Chief of the JIOS and members of the Indi an Orthodontic Society, I exte nd greetings to you from Indi a. You have very diversified postgraduate tra ining in Indi a, H o ll and and in USA. Could you give us a brief background of the treatment philosophies and the app li ance systems you have been exposed to and you are makin g use of them in your practice? Ravindra Nanda : Indeed, well First of all , I want to thank Indi an Orthodontic Society for giving me this opport unity to have a co nv ersat io n abo ut my treatment Philosophy to be published in the Journal. As fa r as your question is conce rn ed, indeed w hat I do now, is a cu lmin at ion of. al l th e different treatment Philosophies, I have been exposed to. My first exposure to Orthodonti cs was in Indi a in Lu ckn ow, w hen I was a stude n t w ith my brother Ram. H e h ad started orthodontic program. I was in hi s first c lass, Predeep Jayna and myself were together in Dental schoo l and also in the Orthodo nti c Program. Ram was a stud ent of Jarabak and he was also a student of Tw eed. So during our two years fro m 1965 and 1966, I was exposed to Tweed and Jarabak treatment philosophy and then I moved to Holland and I had the opportu nity to work there w ith Alan Brodie w ho was doing his sabbat ica l there as a Fulbright Scholar for o ne year. So, then I was exposed to Brodie's Philosophy of No n-ext raction treatment more like univers ity of Illinois co ncept and then w hen he left afte r hi s first year, next two and half to three years I was exposed to w hat Vander Linden was teaching at that time w hi c h was University of 68 Washington Seattle. I moved to Loyala University in 1970 where I was th ere for two years and that's wh ere my first exposure to Bioprogressive treatment started and in the mea ntime, I started teaching students sort of a co nglomeration ofTweed Edgewise Boiprogressive. Th en I got a ca ll to join the new sc hoo l at th e university of Connecticut w ith Charles Burrstone and that's where my first seriou s exposure to Biomechanics sta rted. So, over the l ast thirty three years, I h ave been in Connecticut so what I teach right now is, w hat I would ca ll Biomechanics Sensitive Orthodontics, which is not a technique oriented Orthodontics. It is Orthodontics w hi c h Orthodontist i s in contro l of, becaus e Orthodontist understa nds the diagnosis, treatment plan and wh at patient needs and w hat sort of mechanics he ca n use in hi s app li ance system. Ramesh Sabhlok: Before we start further into the Biomec hani cs, let m e sta rt about the Diagnosti cs criteria you use, when you look at a case and w here do yo u keep yo ur In c i sors? Wh at i s the role of comp uteri zed planning in your practice like Dolphin imag ing system in your sc hool? Ravindra Nanda: First of all , ove r the years I have moved away in my teac hing philosophy fro m ske leta l tissues as a primary diagnostic criter io n to the soft tissues. So these days, I would probably look at the soft tissues first and then I would look at the ske leta l tissues. Peop le are lot more co nsc ious abo ut their esthet ics and I want to see what type of smil e cha nges I ca n create, what type of fac ial esthet ic improvements Rav indra Na nda I ca n create and then on that basis, I dec ide w here I am go ing to place my upper incisors and w here I am going to place my lower inciso rs. We have moved away from those days of lowe r inc iso rs 90 degrees to 95 degrees or FMA of 25 degrees. We think all those numbers are basica ll y averages and eve ry patient sort of demands ow n diagnostic criteria so I am into soft tissue and then the ske leta l tissues. As fa r as our diagnostic criterion is co nce rned, over the yea rs we have evo lved, we used to have our ow n orthodont ic treatment p lan set up. We w ere probably the first o ne to start computerized orthodo ntics in 1973 but th ese days we are usi ng more and more Do lphin System becau se we are a lm ost paperless in o ur department, everything is digital into the laptop. W e don 't take study model s. W e are into E-models, Di gital X-rays, computerized trea tm ent plan of the pati ent, communication w ith the computers so we are more into, what I ca ll 21st ce ntury type of Orthodontics thi s time. Example of diagnosis and treatment planning at the University of Connecticut, Orthodontic Department Diagnosis Database ~------------------------------------, Models (plaster 3D digital) Problems PhotographsExtraoral Frontal Lips lightly touching Lips relaxed Smiling Profile Lips lightly touching Lips relaxed 45° angle ~pr Intraoral Upper occlusal Lower occlusal Right buccal Left buccal Frontal 1ms obe Clinical examination Chief complaint Medical history Dental history Extraoral exam Intraoral exam Functional exam , ... ~ Problems ... Radiographic imaging Panoramic X ray Lateral cephalometric X ray ~ Prob lems Problem list Treatment Synthesis and - . . Treatment - . . Mechanics - . . Treatment - . . Treatment - . . re-evaluation diagnosis objectives plan sequence 69 J Ind Orthod Soc 200 5; 38:68-78 Normofacia l w ith ovo id fac ial form Large interca nthal distance. Wid e alar base. Nose and cupid's bow co in cident. Chin is o n w ith fac ial ML. ILG @ Rest: 2.S mm Incisor Show @ Rest: 3m m Li p competent Asymmetri c fac ial proportion s. Convex ST profil e w ith stro ng soft tissu e Pogoni o n. Protrusive upper lip Sn-Pg lin e and Esthetic pl ane. Everted lowe r lip . LFH : Th roat Depth » 1.2: 1 UL:LL-1 :2 Obtu se NLA. Deep mentolabia l fold • Incisor Show: 100% of upper incisor and 3.5 mm of gingiva. • Unconsonant smile, lowe r lip does not follow the in cisa l line. • No darkness in bu cca l corridors. Adeq uate mal ar promin ences . Max.R 1 obstructing lip c losure. Posteri or gingiva l displ ay M x M L is on w ith fac ial and Md midlin e. 100% deepbite Flared and protrusive 1 Uprighted 1 M x. Peg latera ls. White spot lesio ns o n M x, and Md premol ars. Uneven gin gival heights. No gingival infl ammation Good attac hed/ keratinized tissue in Md anteri o r Good OH 70 JL Rav indra N anda 7654321-12 34567 present. U-shaped arch. Flared upper right 1 and uprighted upper Left 1. Peg laterals. 5 mm of spaci ng 7654 32 1- 12 34e67 present U-shaped arch. Right 6 tipped forward. Flared ce ntral incisors. Class II Mol ar relation ship Class II ca nine. Problem List 1-Pathology and other a. Family history of congenitally missing lateral incisors, and impacted canines. b. Trauma on 1 c. Peg shaped mx. laterals. d. Radiolucency on mx left lateral. e. Mandibular e left still present. f. White spot lesions on upper and lower premolars. g. Mx 8's absent, Mandibular 8's impacted. 2- Antero-Posterior a. Skeletal : Retrognathic mandible, with strong hard tissue Pg. b. Dental: I. Class II molar relationship. II. Class II can i ne relationsh i p. III. Flared 1 incisor and uprighted 1. IV. 10 mm overjet on right central incisor. V. 2 mm overjet on left central incisor. 71 J Ind Orthod Soc 2005; 38 :68-78 3-Vertica l a. Skeletal: I. Normal mi dd le facial height (46%) and II. Relatively sho rt lower facial height (54%) II I. Tip Up pa latal p lane. b Denta l: I. 100 % Deepbite II. Uneven gingiva l heights. III . Extruded upper inciso rs IV. Extruded lower incisors V. Deep cu rve of Spee V I. In c iso r sho w at smil e: 100 %. + 4 mm of gi ngiva . V II. Redunda nt li ps. V III. Deep mento labial fo ld. 4- A li gnment • 3 mm of m x . Crowdin g and no mandib ul ar crowd ing. 5-Tra nsverse • U ppe r and lowe r m idlin e i s o n w ith fac i al mi d line. Treatment Objectives 1-Patho logy/Other a. M o nitor 1. and mx. Left late ral. b. Restore peg laterals. c . M o nitor eruption of 8' s. d . Di sc uss treatment options. 2-Skeleto fac ial: a. Decrease co nvex ity. 3-Soft Ti ssue Profil e a. Dec rease soft ti ssue convexity. 4-0cc lu sa l p lane. a. M aintain the occlu sa l plane. 5-Midlin es a. Upper: M aintain the upper midline. b. Lower: M aintain the lowe r mi d line. 6-Transverse/Arch Width a. M aintain max ill ary and mandi bul ar arch width. 7-A-P/ Incisors: a. Improve overj et. Fl arin g of th e 1 and uprighting th e 1 and fl aring the mandi bul ar incisors. A-P M olars: a. M ainta in upper 6's. b. M ove th e m a ndibul ar m o l ar b y u sin g dentoa lveo lar effect. 8-Verti ca l/I ncisors: a. M x- Intrude b. Md. Intrude. 72 Vert ica l/M o lars: a. M x. Extru de. b. M d.- Extrude. Ramesh Sabhlok: How do you find Do lphin Imaging as compared to other systems ava i lab le? Rav ind ra Nanda: Well , No system is a perfect system . Wh at w e have done is we have used Do lphin system we have c reated so me ch anges, we have sort of tailo red it to our use and it works very w ell . Being an educat ional in stitution taking ca re of th e res idents and large number of patients it works very nice ly fo r us. Ram esh Sabhlok : Wh at is yo ur m ain criterio n of selection regard ing th e extracti o n and non extractio n cases? Because over the number of yea rs the pendulum is sw inging thi s side and th at side. Wh at are the most important factors you w ill base your dec isio n regard ing extracti on/ Non-extraction cho ice? Ravindra Nanda : Aga in, it is tru e w e have changed our criteri a for extracti o n and no n-extraction. I always start at Esthetics first. Th ere was a time w hen w e would extract fo r 4 to 5mm of space sho rtage but, these days o ur criteria is more based on mo lar relati onshi p. If a pati ent is adult and has a full class II mol ar relat io nship most probab ly I w ill extract in a pati ent li ke that to accommodate all the teeth into th e arch because I do not wa nt to subj ect an adult pati ent into headgears or c l ass II e l as ti cs or o th er appli ances w hi c h nee d compli ance and not as comfo rtable. So, I loo k at the Orthodo nti c Treatment Sequence MAXILLA MANDIBLE Consult with prosand endo Consult and Seps Band 6's Band 6's Bond 5 t05 Bond 5 t05 Align mx. Teeth Align md. teeth Intrude upper incisors. Intru de lower incisors. Use -6 degrees torque brackets. Get into a heavy wi re 21x2 5 Get into a heavy wire 19X25 Place TFBC Place Twin Force Bite Corrector Class II elastics Class II elastics Finishing Finishing Retention with a wrap around Retention with fixed 3 to 3.. )L Esthetics first, then I am going to look at the amount of the crowding, then I am going to look at whether I am going to extract in the lower or in the upper. So, as a rule in children now our extraction percentage has dropped down to may be to 15 to 20 percentage. In adults extraction percentage is still very high because of the absence of the growth factor. Ramesh Sabhlok: What is your criterion In Border line cases? Ravindra Nanda: There are no more border line cases anymore. That terminology has gone down the river because borderline cases are all non extraction cases. Ramesh Sabhlok: Biomechanics in Orthodontics has been forgotten for years. Recently the Orthodontists have started payi ng attention to it. What are your perceptions about this? A lot of clinicians find biomechanics very difficult and too theoretical. Why is it so? Why is not biomechanics a bigger part of all Orthodontists training? Dr. Ravindra Nanda: See! I think We started Biomechanics on a wrong footing because the people who were teaching Biomechanics in the past were very, what I will call it puritanical , in other words everything had to be pure, there was no compromise, there was no meeting of minds and there were systems devised, there were techniques used, which were very difficult to use, very difficult to execute on the patients and the net result was that they were not very practical in a busy office. One of the things over the years which I have done is I have made Biomechanics what we call user friendly. So, Biomechanics does not have to be difficult Biomechanics and the example I always give of pharmacology. Like in Medicine, you can not think of giving a medication to a patient without knowing what dose to give, how long to give, what are going to be the side effects. Similarly, force in orthodontics is our pharmacological medicine because we got to know what type of force to give, how much, for how long, what direction, what is the centre of resistance and then. what are the side effects going to be. So, why it is not being taught in Orthodontic schools is because of the ignorance of the teachers, because the teachers were not exposed so they do not want to show what they do not know to their students. So, the net resu It is it conti nues on and on and on. It is not a problem in India it is a problem all over the world because I travel all over the world same question is asked all over the place . So, university of Connecticut has done Ravindra N anda a great like thirty three full time teachers, five to six Orthodontic Chairman, couple of deans were teaching. We were trying to tell people th at Biomechanics is important. Biomechanics is not a treatment philosophy. Biomechanics is th e basis of Orthodontics. It could be a part of straight wire, it could be a part of Bio-progressive it could be part of any technique. So all we have to do is to understand how a force system works. So all I wish is that one day all the orthodontic professors and instructors should get together in a room and for three to five days all the basics done so that they can go back and start their students and telling them how important the biomechanics is. That is the only way to do it because you can not teach the students even the professors do not know about it. Ramesh Sabhlok: What are some examples of biomechanically oriented appliances? And what are the advantages of using biomechanically oriented appliances? Ravindra Nanda: There are many biomechanically oriented appliances as you probably heard today. I talked about, what I call in Orthodontic smart wi res. Intrusion Arch Fig. 1: Schematic diagram of the moments and forces created by an intrusion arch 73 J Ind Orthod Soc 2005; 38:68-78 Fig.2(a): Patient with a deep bite and a CI II maloccl usion at th e initi ation of the treatment Fig 2 (b): Intrusion arch in place, is correctin g the deep bite and tipping back the max ill ary molar Fig.2 (c) : Patient at the end of the treatment with and id ea l overbite and correction of the Class II malocclusion 74 Rav ind ra Nanda 7~ - ,-~.- ,.. These are the w ires w hi ch use spec ial memo ry all oys, th ey use specia l o rth odo nti c bends, un derstanding of moments and fo rces and we ca n deve lop w ires such as intru sio n w ires. We ca n use intrusio n w ires (see figure 1 and 2), but they ca n do extru sio n for us, th ey ca n do space closure fo r us, they can co rrect the mi d lines for us, th ey ca n correct the occ lu sa l planes . So, o ne w ire has the ab ility to do va ri ous fun cti o ns th at is the smart w ire. I ca n have a space closure loop w hi ch w ill deliver a contro lled tipping, translati o n as well as root upri ghting over a five mo nth peri od o r a fo ur mo nth peri od. All th ree movements will take pl ace w ith o ne activati o n. So th ere are w ires w hi ch are much easier to use th ese days and lot of these th ings you are go ing to see in my fo rth coming boo k w hi ch is coming up. Ramesh Sabhlok: Wh at is the name of th e book? Ravindra Nanda : Th e boo k w hi ch 'is go in g to be publi shed w ill be in my hand is go ing to be in A pril of thi s year in coup le of mo nths. Th e titl e of th e book is Bi o mec h ani c and Esth et i c St rateg i es in C l i ni ca l Orthodo ntics and so fa r I have bee n very lu cky to have some ve ry nice peo pl e p art ic ipate in co ntribu t in g chapters w ith me. Ramesh Sabhlok: So it wi ll be d iffere nt from th e ea rl ie r book? It w ill be very d ifferent th an the earli er book. It is very clinica l. It talks abo ut O rthodo nti sts using impl ants to move the teeth. It talks about using impl ants to how to correct th e non - surgica l open bi te. It has three chapters on class three pat ients. It has chapters o n space cl osure, new smart wires, new Intru sio n w ires. It has chapters by Vi ncent Ko ki ch, Bjorn Zac hri son, Sunil Kapil a, H arry Legan. So, I have inv ited six to seve n chapte rs by my fri ends and ba lance o f the chapte rs by myse lf and by my co ll eagues fro m unive rsity of Connecti cut. Ramesh Sabhlok: In your book o n "B iomec hani cs in Clini ca l Ort hodo ntics" edi ted by you, Class II treatment gets lot of atte ntio n. Wh y? Ravindra Nanda: Yes, In the last boo k there was lot of emphasis was o n class II. Th at is W hy as I have j ust mentioned that in the forth coming book we w ill have th ree chapters o n class III. O ne is w ritten by my fri end Frank Chang fro m Taiwa n, o ne is by o ne o f m yo id stud ent Gingi Su guwa ra fro m Japan and one chapter is w ri tte n by me. So, we are cove rin g w hat I would ca ll Pseudo class III patients, protract io n H eadgea r and the cu rrent protoco ls of co rrecting c lass III , im p lants and th en all the clini ca l problems in a seq uenti al manner in thi s boo k. Ramesh Sabhlok: D o b io mec hani ca ll y orie nted app li ances give a mo re opt imal b io logic respo nse for tooth movement th an oth er types of appli ances? Ravindra Nanda : O ne hun dred pe rce nt. Thi s is a correct statement. Th e reaso n for th at is th at, a biomec h ani ca ll y correct app li ance system de li vers a optimal fo rce, a force whi ch is very low because you are usin g a low load -d eflec ti o n rate, fo rce is not acti vated eve ry time. You acti vate the fo rce fo r a lo ng dista nce, fo rce di ss ipates very slow ly, and decay is very slow, the tooth movement is much bette r. So, all th ese app lia nces w here you are acti vatin g fo rce all the time, you are putting in too mu ch of fo rce and I do not thin k you are gettin g very good orthodonti c tissue respo nse and the defini tio n of a good ti ssue respo nse is no root reso rpti o n, treatm ent fini sh in pro per time and no side effects. So, if you are not go ing to have side effects then you are go ing to have not treatm ent w here you move crown o n o ne side and then spend tim e to move the roots o n the oth er side. So, we are do ing sho rter treatment time, lo nger v isits, lowe r force va lues and mo re w h at I wo ul d ca l l pred i c t ab le orth o d o nt i c treatment. Ramesh Sabhlok: Yo u have rece ntl y introd uce d Nanda's Biomechani ca l App li ance System ? Wh at are the m aj o r adva nt ages over the o th er pre-adju sted syste m s? Ca n yo u te ll u s so m ethin g abo ut yo ur prefe rence about slot size? Ravindra Nanda: W ell, you may say I have introd uced a N ew System . It is not rea ll y a new system . It has been pac kaged into a new system because lots of time peop le get very confused. Ove r the yea rs, I give about 14 to 15 courses all over th e wo rl d . I v isit may be about 12 to 13 countri es and every tim e I go, peop le always say, Ca n you give me seq uentiall y how to correct it? w hat is the w ire sequence? how you correct it? So, we went ahead and said o kay, we woul d like to have a bio mec hani ca l system w here the brac kets w ires are cohesive ly tied together and the tooth respo nse is tied together to w hat you are trying to ac hieve and that is w hy we ca ll thi s app lia nce system. So, you ca n not com pa re thi s w ith any oth er Pre-adju sted app lia nce system because in our app li ance system we have the brac kets, we h ave the w i res and th ese w i res are spec iall y designed w ires, spec ial loops, specia l be nds. 75 J Ind Orthod Soc 2005; 38:68-78 So, we are gettin g more predi ctabl e Orthodontic response. As far as our brackets are co nce rn ed we spent lot of time designing our brackets. W e beli eve in a torqu e system of 1 7 degrees for centra l in cisors, 11 degrees f?r the lateral incisors and so on. We feel that a Orthodontist should dec ide what wire bracket interface is go ing to be needed to finish a pati ent rath er th an a bracket to decide what type of wire one ca n put in at the end of the treatment. So, W e are not in favor of using a lower torqu e brackets because 9 degrees 11 degrees you wi II have to put in 0215X025 w ire to exp ress th at torque while in 17 degrees I ca n put a mu ch lower dimension wire to express th at amount of to rqu e in my wires. So, as far as the other things of th e bracket, we designed th ese brackets with the help of engin ee rs, who are very versed with the aircraft industry w here you are go ing to use N atos which are go in g to be fatigue res istance because of changes in the temperatu re o f the ai rcraft engines. So, what we are using is a spec ial mim system and we got rid of th ese bonding base which people have used over the years and we have cut down th e amo unt of th e thi ck ness of th e bracket by usin g a specially designed mec hani ca l lockin g system, So th at w hen we are bonding, our brea kage rate of the brac kets or loose brac kets is extremely low. Th e brackets are very low profile they are angul ated alo ng th e lo ng ax is of the teeth so that th ey are close r to the centre of the resistance when w e are placing arch wires in th ere. So, these brac kets have what we like them but as I always say that brackets do not make a patient good o r bad. Brac kets o nly help us attach the w ires If the brackets have certain characte ri st ics w hi ch are good it helps you to fini sh a pa ti ent better so, how and w hat you. p.ut into a bracket is finally go ing to determin e w hat It IS. SO, N and a Biomec hani ca l system is mo re dependant upo n the w ires less o n th e brac kets Ramesh 5abhlok: Yo u have in co rporated minu s 7 degree torqu e in th e upper ca nine brackets and there are many prescriptions like Ri cketts, Hilgers and So ndhi incorpo rate plus torque in the upper ca nine brackets, these days more and more peopl e like fuller smiles. Sometimes th ere are buccal corridors and dark areas . Some of the prescriptions in corpo rate plus torque in th e ca nine brackets. Wh at do you think about this? Ravindra Nanda: Th ere is a resea rch, w hi ch we are fini shing at this tim e which basically corrobora tes our wo rk . What we did is we looked at severa l hundred patients, their smil es, espec ially using mov ie ca meras 76 and different types of treatments th ese individu al patients have go ne throu gh. Wh at we find is that ca nine is not th e pil lar, which defines a smile or which defines th e co rn ers of a mouth, because our resea rch is showing th at 40% of th e patients in th eir smil e are go ing to show their first pre-mol ars, the other 38 to 39% of the patients show the second pre-molars and there are.anly very small number of patients will show th e mes ial of the first mol ars o r th e second molars and th e ve ry smal! percentage of th e pat ients who only show ~a nin es when they smile. So, th e ca nine does not enter Into the estheti c aspect or enter into the dark corn ers o r all those aspects. Those are the posterior teeth which are .goi n.g down i nto the co rners . Now, as far as ca nin e IS co ncern ed one of the bi g problems not hav in g mu ch large r negat ive to rqu e is that you leave these cuspid s hanging down while th e lower cuspids are basically not following th e arc h form of th e pre-mol ars. Lowe r pre-molars buccal inclination is linguall y in clined. So you must have lower ca nine follow th e pre-molars. When you do th at you end up having about 3 to 4 mm of overjet in the ca nine area. W e do not like th at, W e think that a ca nine which is sli ghtly tu cked in gives o nl y 1 mm. or so of overjet in the ca nine area gives a mu ch better smil e and as you probab ly saw in all our finished patients when I give th e esth eti c lecture day after tomorrow you will see I will further expa nd o n this o ne th ere. Ramesh 5abhlok: Wh at is your usual Protocol in Orthodontics w hen you start a new case? Ravindra Nanda: W ell , our message always is th at every patient is an individual and no patient is go ing to fit into averages o r numbers o r any thing. 50, w henever you look at a patient, see that is the first p a tie~t yo.u have ever see n in your life and th e problem patient IS presenting is th e first problem you have ever seen in your li fe. So this way you are lookin g at a patient w ith very fres h eyes beca use when you look at a patient w ith fres h eyes you will see lot of thin gs w hi ch no rm all y you do not. If you are ju st classifyi ng patients into say i ng like he is class II Division II, then you are go in g to mi ss out lot of things. So, for us the clini ca l exa min atio n is o ne of th e most important parts, facial exa min at io n, intra-o ral exa min at ion lateral fac ial photographs are extremely impo rtant for us. W e take lateral views, frontal v iews, 45 degree views we take what we ca ll posed smil e, we take smile in happiness, we take re laxed lip position. So a full analysis of pati ent's face is very important. Cep halometri cs- we will use cep halo metic Ravindra Nanda Mushroom Loop Fi g.3: Schematic diagram showi ng the moments and fo rces on the mushroom loop. Fig.4: Extra oral activation of mushroom loop prior to insertion Fig. 5 : Patient with a mushroom loop placed to achi eve retract ion of the max ill ary ante ri ors analysis to understa nd the patient's skeletal relati o nshi p pattern . But everything has to sort of tie in and th en o ne of th e most important thing is w hy th e patient is th ere, w hat the pa ti ent is looking fo r, w hat is the patient's comp laint and that should never be ignored. II occ lu sio n, your bite is closed". After all that th e patient w ill say, "docto r, w hat about my inciso r because you never mentio ned th at I w ill co rrect your incisor also?" So, it is very impo rtant for the patient to li sten about the main compl aint. Ramesh 5abhlok : 50 the pat ient's chi ef com p laint should be taken into co nsiderati o n Ramesh 5abhlok : So, over th e num ber of yea rs we are going away fro m the A ngle's classificatio n. Now we are looking at th e faces, at the soft tissues analysis. So, our thinkin g has changed more towa rd s soft tiss ue analysis? Wh at is your pe rceptio n? Ravindra Nanda: Al ways, because a pati ent may come to you to get the lateral in ciso r corrected and you are ta lking to the pati ent abo ut the bu cca l occ lu sio n or cross bi te but, te ll the patient th at you are go i ng to take care of the lateral inc iso r. It is very impo rta nt fo r the pati ent to hea r, because lot of the ti me, my residents are ta lking w ith th e pati ent, "Oh, you are having c lass Ravindra Nanda: Extremely im po rta nt, I always tell my students th at the most important thing is re lati o nship of th e anteri o r teeth to the smi Ie, to the li ps, the verti ca l dimensio n and the ca nine relatio nshi p. Wh at goes o n 77 J Ind Orthod Soc 2005; 38:68-78 in the bac k, depe nds on w hat your trea tm ent plan is. If you have extracted o nl y in the upper you may have a c lass II mo lar, if you have not extracted you sho uld have a class I mol ar, if you have extracted ra rely in th e lower arch you may have a class III mo lar relationship . So, th e q uestion always is anteri or teeth are quite sepa rate tha n the posterior teeth. You have to ali gn them toget her but you look at th e anterior teeth quite d iffere nt th an you look at th e posterior teeth. Ramesh Sabhlok: Wh at will you lik e to tell u s somethi ng about the Anchorage preparation in different c lini ca l situ at io ns, espec i ally in m ax imum and minimum anchorage cases? Ravindra Nanda: Yo u see, our concept of anchorage is very different. In my last book, I had covered thi s concept in detail but in the new book I left that part there. W e thi nk anchorage as four sepa rate concepts. M ost of the time people always stop at th e first co ncept and the first co ncept always is to increase th e anchor units, use additional anchorage with headgear, cl ass II Elastics, Lip Bumpers, palatal arc hes, thin gs like that. For us that is a tradition al anchorage. But, the second concept is very important that is, what we ca ll the magnitude of force, diffe renti al fo rce, so we use that in favo r, different force in the posterior region, different in the anterio r region. Th e third co ncept is differenti al moment-to-force ratios. W e can use differe nt momentto-fo rce ratio in the back as well as in front so th at we can pit them against each other. And the fourth concept always is the Biologi ca l. You know that means that how the bone is, how th e tissues are, whether you are treating adult, whether you are treating young. So, these are all concepts of anchorage which are quite different than other people. Ramesh Sabhlok: I b e lieve that you believe in Segmental arch techniqu e in Connecticut over the number of years when Charles Burstone introdu ced? What is your retraction mechanics in extraction cases? How do you preserve the anchorage in different clinical situations? Ravindra Nanda: Dr. Charlie Burstone retired in 1992. We have not used segmental arch philosophy since that time. University of Connecti cut was never 100% 78 segmented arch. Segmented arch was o nl y may be 15% of the trea tm ent w hi ch w as done. So th e majority of t he tr ea tm en t was done what we wou Id ca ll Biomechan ica l approach in co nventi ona l Ed gew ise Orthodonti cs. So, we do not use segmenta l mec hani cs fo r retraction at al l any more. Our concept is mainly makin g orthodontics user friendl y. So, incorporating the concepts of Biomechani cs, Segmental philosophy into th e conventi onal Edgew ise because people want to treat more patie nts, peopl e wa nt to treat faster, people want to treat with th e app li ance system which looks good in the book but th ey also wa nt to look good in th e patient's mouth. Ramesh Sabhlok : In maxi mum anchorage cases w ill you retract the ca nine individu all y first, fo ll owed by retractio n of the incisors to preserve the anchorage or you wi II retract en-m ass? Dr. Ravindra Nanda : W ell , it does not m ake the difference to us whether you retract individu ally o r enmass because the fo rce values are almost the same for us. So, someti me we retract enmass sometim es w e do not. But, if I am using sliding mechani cs, I usua ll y use my intru sion arch as a pi ggyback top wire in the mo uth to give a moment o n th e posterior teeth to keep them back, use intrusion wire in th e fro nt so that the bite does not get deepen and I ca n use even 016x022 or 017x025 55 wires to retract the ca nines or I ca n use my new CNA wires which is our new Beta titanium wire which we use to makeour Mushroom loops (see Fi gure 3, 4,5). And mushroom loops w e are using more over the T-Ioop beca use the probl em with the T-I oop is th e horizontal part was very large and it was always di gging into th e tissues so we wanted to make it more user friendly So, we made the T-shape into a mushroom shape by shaving off th e co rn ers and the then loop also becomes little bit more biomechanically nice because now it has a archial shape. So, when you open the loop the spring wants to close at the same time the horizontal part is very small and the loop is more efficient. (To be continued in next issue) Communications Dr. Ravindra Nanda - [email protected] Dr. Ramesh Sabhlok - [email protected] I ) '~ - We've Got You Covered! We're all you need ... Leaders in the industry with the most innovative, high-tech products at unbeatable prices. We have a full-line to meet all your orthodontic needs. On-going R&D and an unparalled sales and support staff puts you on the leading edge and keeps you there ' In the USA : 800.547.2000 Fox : 800.888.7244 M ar gie W@Ort ho Or g a nize r s .com InternationaI760.471.0206 Fox : 760.471.9549 Darl en eM @O rt hoOrg a n ize r s .co m 1619 S. 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