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Original Researchcombination with the 0.019 × 0.025-inch TMA wirethan with the SS wire of the same dimension. Thisdifference was significant (P ≤ .05). These highfrictional forces are caused by the surface propertiesof the TMA wires. TMA has more porositiesand a noticeably rougher surface than SS. Thesefindings are in agreement with those of Angolkaret al. (1990) 2 and Drescher 7 et al. (1989), who alsoobserved higher frictional forces with TMA wires,compared with SS wires.Studies have proved that ageing of Opal selfligating brackets have showed significant increasein frictional qualities C.A.Reicheneder et al 6. Withall types of archwires, aged Opal Brackets exhibitedgreater frictional forces than new Opal brackets. Thisincrease was significant for Opal brackets aged for 9– 10 and 18 – 20 months with respect to SS wires. Thenegative influence of ageing on frictional behaviourmay be due to abrasion of bracket material causedby alternate warm and cold cycles in the chewingsimulator. This wear and tear resulted in increasedsurface roughness and probably in an accumulationof debris in the slot, which, in turn, increased friction.The results are in accordance with those of Riley 18 etal. (1979), who found that friction of polycarbonatebrackets gradually increased in distilled water dueto corrosion, and the results of the study by Keith etal. (1993) 14 on ceramic brackets.The current study results support previousinvestigation by C.A. Reicheneder6 (2007) bySims et al. (1994)15, Read-Ward 12 et al. (1997),and Kusy16 (2001), who also found self-ligatingbrackets to produce significantly less friction thanconventional brackets. Schumacher 17 et al. (1999)also reported reduced friction with Damon SL selfligatingbrackets in comparison with conventionallydesigned brackets, despite the fact that this decreasewas associated with negative side-effects in terms oflevelling losses after completion of retraction.Small differences in the torque prescriptionsbetween the active and passive brackets were notexpected to influence the outcome because thesewere outweighed by the large free play that was morethan two times higher than the torque differencesin a conventional bracket. RCT with the body ofevidence on this issue suggest that the bracket-archwire free play might not be the most critical factorin altering the tooth movement rate. This situation,however, changes drastically as treatment progressesand wires of higher stiffness are engaged in thebracket. Correction of rotations and achievementof proper buccolingual crown inclination (torque),which are frequently required in mandibular andmaxillary anterior teeth, respectively, necessitatea couple of forces. This assumes the formation ofcontacts of wire inside the bracket slot walls, andthus the major advantage of self-ligating bracketfree play is eliminated as the crowns gradually attaintheir proper spatial orientation.Especially for torque application, self-ligatingbrackets lose more torque compared withconventional brackets, whereas a clinical trialshowed that these brackets can achieve comparabletorque transmission only with reverse curve ofSpee archwires. Alternatively, torquing auxiliaries,higher torque prescription brackets, or pretorquedwires can be used to counteract the greater torqueloss from greater free play.These investigations demonstrated clearly thatminimal amounts of friction are generated withfour types of passive self ligating brackets thatare commercially available. The literature reportsvalues of frictional forces for active self ligatingbrackets that are five times greater than passive selfligating brackets.ConclusionThis (in vitro) study measures the frictional propertiesof different aesthetic brackets and semi aestheticself ligating brackets. The results demonstrate adifference in the friction produced by self-ligatingaesthetic and self ligating semi aesthetic brackets.Self ligating Semi aesthetic brackets had smalleramount of friction when compared to Aesthetic Selfligating brackets. Among the Four types of Selfligating brackets Damon 3 showed least amount offrictional forces. The difference was significant (P≤.05). TMA wires demonstrated more frictional forcesthan SS wires in all the four types of self ligatingbrackets. Opal self ligating brackets showed leastamount of friction with 19x25 TMA wire comparedto other four types.References1. Andreasen G F, Quevedo F R 1970. Evaluation offriction forces in the 0.022 ×0.028 edgewise bracket invitro. Journal of Biomechanics 3 : 151 – 160554Indian Journal of Multidisciplinary Dentistry, Vol. 2, Issue 4, August-October 2012
Original Research2. Angolkar P V, Kapila S, Duncanson M G, Nanda R S1990. Evaluation of friction between ceramic bracketsand orthodontic wires of four alloys. American Journalof Orthodontics and Dentofacial Orthopedics 98:499 –5063. Baker K L, Nieberg L G, Weimer A D, Hanna M 1987.Frictional changes in force values caused by salivasubstitution . American Journal of Orthodontics andDentofacial Orthopedics 91 : 316 – 3204. Bednar J R, Gruendeman G W, Sandrik J L 1991.A comparative study of frictional forces betweenorthodontic brackets and arch wires. American Journalof Orthodontics and Dentofacial Orthopedics 100:513 –5225. Bourauel C, Drescher D, Thier M 1992. An experimentalapparatus for the simulation of three-dimensionalmovements in orthodontics. Journal of BiomedicalEngineering 14: 371- 3786. C.A. Reicheneder, U. Baumart 2007. Frictional propertiesof aesthetic self ligating brackets and conventionallyligated aesthetic brackets. European Journal ofOrthodontics 29: 359 - 3657. Drescher D, Bourauel C, Schumacher H A 1989. Frictionalforces between bracket and arch wire. American Journalof Orthodontics and Dentofacial Orthopedics 96: 397 –4048. Drescher D, Bourauel C, Thier M 1991. OrthodontischesMeß- und Simulationssystem (OMSS) für die statischeund dynamische Analyse der Zahnbewegung. Fortschritteder Kieferorthopädie 52: 133 – 1409. Henao SP, Kusy RP. Frictional evaluations of dentaltypodont models using four self-ligating designs and aconventional design. Angle Orthod 2005;75:75-8510. Ireland A J, Sherriff M, McDonald F 1991. Effect ofbracket and wire composition on frictional forces.European Journal of Orthodontics 13 : 322 – 32811. Kusy R P , Whitley J Q , Prewitt M J 1991 Comparisonof the frictional coefficients for selected archwire-bracketslot combinations in the dry and wet states . AngleOrthodontist 61:293-30212. Read-Ward G E , Jones S P , Davies E H 1997 Acomparison of self-ligating Andconventional orthodonticbracket systems . British Journal of Orthodontics 24 :309 – 31713. Stannard J G , Gau J M , Hanna M A 1986 Comparativefriction of orthodontic wires under dry and wet conditions. American Journal of Orthodontics and DentofacialOrthopedics 89 : 485 – 49114. Keith O , Jones S P , Davies E H 1993 The infl uenceof bracket material, ligation force and wear on frictionalresistance of orthodontic brackets .British Journal ofOrthodontics 20 : 109 – 11515. Sims A P , Waters N E, Birnie D J 1994 A comparisonof the forces required to produce tooth movement exvivo through three types of pre-adjusted brackets whensubjected to determined tip or torque values. BritishJournal of Orthodontics 21 : 367 – 37316. Thorstenson G A , Kusy R P 2001 Resistance to sliding ofself-ligating brackets versus conventional stainless steeltwin brackets with Secondorder angulation in the dry andwet (saliva) states American Journal of Orthodonticsand Dentofacial Orthopedics 120 : 361 – 37017. Schumacher H A , Bourauel C, DrescherD 1999 The influence of bracket design onfrictional losses in the bracket/arch wire system. Journal of Orofacial Orthopedics 60: 335 – 34718. Riley J L , Garrett S G , Moon P C 1979 Frictionalforces of ligated plastic and edgewise brackets. Journalof Dental Research 58 : 98 (Abstract)Indian Journal of Multidisciplinary Dentistry, Vol. 2, Issue 4, August-October 2012 555
Page 1 and 2: From the Editor's DeskFROM THE EDIT
Page 3 and 4: Reliability o f Lo w e r Lip Li n e
Page 5 and 6: DiscussionOriginal ResearchIn curre
Page 7 and 8: Original Research31.23 degrees, for
Page 9 and 10: COMPARISON OF FRICTIONAL RESISTANCE
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Page 16 and 17: Review Articlediagnostic biomarkers
Page 18 and 19: eview articleCo n c e p t o f Short
Page 20 and 21: Review Articleincreased when unilat
Page 22 and 23: Review Articledimensionally accurat
Page 24 and 25: Review Articleassociated with incre
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Page 28 and 29: Review ArticleTreatmentSome of the
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