Lingual Bracket Jig
Transcription
Lingual Bracket Jig
Dr. Mazor Yoav A specialist in Orthodontics & Dento-Facial Orthopedics. Member of the Israeli Orthodontic Society. Graduated Dental School at the Tel Aviv University on 1990 Clinical instructor & a lecturer at the Prosthodontic dep. for more then 10 years. Today: Orthodontist “Shiba” hospital – Special needs Specialization program in Orthodontics - Bulgaria. Professional advisor for R&D. Professional manager of a 12 branch Policlinic. Lecturer WHY Lingual Orthodontics? More adults - Invisible - Not interfere with their everyday function & physical appearance. What can we offer them? What alternatives: Ceramic brackets Clear Aligners Lingual Orthodontics History of L.O 1841 Pierre Joachim Lefoulon lingual arch for expansion & alignment 1975 Craven Kurz- USA Used plastic brackets – easy to adapt to anterior lingual surface. Only Invisible, please -Debondings -Uncomfortable Modern lingual appliance – “K. Fujita” Japan 1978 – introduced his method. 3 piece bracket 3 slots: V, H, Oc. Commercial interest – Ormco (Kurz) 1st generation (1977) – 7th generation(1990) 1st 2nd - add hooks 3rd - add hooks on molars 4th - profile change for easier wire insertion 5th - bite plane, more torque, accessory tube 6th - longer hooks 7th - romboid bite plan to increase IBD, PM longer slot The American Lingual Orthodontic Association – 1987 1987 AAO – Disappointment - Poor results - lack of study & experience - poor laboratory systems - inadequate training - lack of preformed lingual archwires. The first Buccal clear brackets were presented… A company – “starfire” The European Society of Lingual Orthodontics - 1992 France Fontenelle – 1978 – first publish Fillion Didier – research, publish, lecture. ESLO + Alaine Decker – Paris V - lingual program Italy Massimo Ronchin (1st president of ESLO) developed in 1994 the L- SLB (Forestadent), 2D lingual brackets- MTM Giusepe Scuzzo (3rd) with Takemoto – STb (Ormco), book Germany Dirk Wiechmann – customized approach – individual wires (robot), Incognito (3M) Israel Silvia Geron – lingual bracket jig Korea Kim & Kyung (MS) Japan Largest lingual association today. 1996 – the first study cub (Kurz, Laughlin, Creekmore, Wildman, Scuzzo, Fillion…) Evolution of the Lingual systems - Buccal brackets, direct bonding. - Commercial lingual brackets, direct bonded - Commercial lingual brackets, laboratory, indirect bonding, SW - Commercial lingual brackets, laboratory , indirect bonding, individual customized wires. - Laboratory, individual customizes lingual Brackets, individual customizes wires, indirect bonding. Developments - “light” lingual Orthodontics (2D systems, MTM) -lingual SLB - Harmony-AO, eBrace-Riton, - Forestadent, GAC.. - MTM -Special wires – bidimensional, double offset -Lingual jigs – Silvia Geron The different Laboratory approaches Indirect Bonding: Important. Presents the total value of the laboratory work: • Accuracy – setup, visualization, access, anatomical variances.. • Reduced chair-time. 2 layers: Hard, soft: eBrace / Kadent 1 layer – Medium. Additional type Silicone (Polivinil Siloxan) soft & hard (Putty & wash) CLASS System – Custom Lingual Appliance Setup (Ormco) Malocclusion model & a Set-up model Bracket positioning on set-up model A photo is taken for wire fabrication “Cap” fabrication The brackets are transferred to the malocclusion model – Cap. Transfer tray fabrication. Advantage Set-up model: early visualization. Disadvantage Many steps – errors – may require finishing steps TARG - Torque Angulation Reference Guide (Ormco 1984) The buccal surface & a specific blade are used for the lingual positioning. Allows accurate individual torque and angulation prescription. Only malocclusion model – mounted on a swivel base, teeth are aligned to a blade which is tilted to a specific torque & angulation “virtual” setup- resin customized base brackets are bonded on the malocclusion model with specific prescription for each tooth. But since the TARG machine does not consider the different thicknesses of the teeth, many 2nd order bends are required. BEST - Bonding with Equal Specific Thickness Fillion 1986 “Electronic TARG” Improvement of the TARG – which compensate for the teeth BL different thicknesses & allow SW approach. The lingual brackets are bonded on the malocclusion model with the specific prescription for each tooth, no set-up. The wires are fabricated with the help of computer software (DALI) according to the data generated from the specific prescription of each tooth, fabricating the ideal individual wire. LBJ - Lingual Bracket Jig “Geron” Israel The only system which allow direct & indirect bracket bonding. The system consists of 6 upper anterior teeth & 1 universal jig for the posterior teeth & a specific ruler. The jig allows to transfer a labial prescription to the lingual surface & BL thickness compensation. It can be used with any prefabricated lingual bracket. The disadvantage is the limited number of prescription jigs available. KISS - Korean Indirect Bonding Set-up Korean Society of Lingual Orthodontics members. Accurate set-up model & a machine which positions all brackets in one time. Allows posterior & anterior height differences in set up for intrusion / extrusion. HIRO System - Hiro Japan, Takemoto & Scuzzo. Do not require any specific equipment. Set-up model with perfect teeth positioning. Brackets are positioned & placed on a 018X025 SS wire. Individual resin transfer trays are fabricated & used as indirect single tooth trays. Advantage – low cost, simple Disadvantage – long chair time at bonding, tray sensitivity. Simplified Technique - Ormco, STb Developed for the STb brackets. Direct positioning on the malocclusion model: anterior brackets at 1.5-2 mm from incisal, canines at 2.5-3 mm, posterior teth at the center of the clinical crown, indirect individual bonding tray using warm glue gun Advantages – fast, low cost, simple Disadvantage – compensating bends… 1.5-2 mm 2.5-3 mm center TOP Transfer Optimized Positioning - “Wiechmann”, Germany (2001) The technique uses a set-up model as the BEST (Fillion). Here the brackets are bonded directly on the malocclusion model with NO BL compensations. The compensations are made by an individual lingual wires which are fabricated by a robot. Most of the prescription is “in the wire” & the correct wire must be used & fully sited. CAD CAM systems - Incognito (3M), eBrace (Riton), Harmony (AO) The later format of the system, the brackets are designed by a computer software to maximize the bracket pad to the tooth form. The Brackets & wires contain a specific prescription for each tooth Advantages & Disadvantages of Lingual Orthodontics disadvantages: - Expensive. (Materials, laboratory, chair time) - Relatively more discomfort to the patient. - More difficult for the operator (bonding, rebonding, biomechanics view, manipulation) - “laboratory dependency” (Indirect bonding). - Limitations (Anatomical, periodontal, esthetical, OH, case selective). advantages: - Good esthetics - Invisible - Good control & results - Visualization of progress – dental, gingival - Not affecting the buccal enamel - Beneficial in some clinical procedures Anterior intrusion / Posterior extrusion Maxillary arch expansion Maxillary molar distalization Habits – tongue training, bruxism TMJ deprogramming Maxillary molar distalization & expansion. More bodily – CoR is more palatal to the long axis Basic Lingual Approaches & systems The conventional lingual bracket 1. Anterior bite plane 2. Wide base 3. Hooks 1 3 2 Vertical slot tip control - posterior teeth Horizontal slot Horizontal slot torque control – anterior teeth Vertical slot 1. Commercial lingual brackets - Laboratory adapted Those systems use commercial premade brackets & wire The brackets are adapted to the patient’s lingual tooth side by adding composite on the lingual bracket pad. Considered also as SW lingual systems Mushroom 1-5 Ormco 7th generation (Kurz) (1990) Rounded contours Large hook for attachments Increased tie wing area, to enable double over tie Bracket base is large to improve bonding. Horizontal slot allows easier torque control. Bite plan in the upper anterior brackets to plan direct the occlusal forces through the center of resistance of the anterior teeth, opening the bite and creating intrusion of the upper and lower anterior teeth. Molar - twin brackets/ tubes with mesial ball hooks. ORG – ORJ- Romano-Geron Mid form - 7th & STb American Orthodontics Small, narrow and smooth Horizontal slot .020x.020” Auxiliary vertical slot STb (ORMCO) (Scuzzo-Takemoto brackets) Forestadent 2D, 3D, SL Low Profile Adenta - Evolution a self-ligating lingual bracket Modified Hiro system GAC Innovation-L self ligating brackets “Phantom” Lingual wires The lingual arch-wire is mushroom like with a 3-4 mm inset between the upper 3-4 & a 2-3 mm between the lower 3-4. A smaller inset is made at the transition between 5 & 6 Premolar inset Molar inset New Pre-fabricated Bi-dimensional wires. Pre-fabricated double offset SW 2. Systems use commercial premade brackets, which have no adaptation or compensations Commercial lingual premade wires which are bent by the operator (MTM, social 6, 2D) Laboratory fabricated individual lingual wires – (“Sure-smile”, Top) Bring the Control to US. Choose between buccal and lingual braces, combine between different bracket systems- and yet- get full coordination of the arches! Visualize the bone coverage on every tooth (if needed) No miracles..! Let the orthodontic knowledge have true expression and influence. 3. Cad Cam individual lingual bracket systems. Those systems are computer supported. The brackets & wires are digitally 3D individually designed. Each tooth have a custom made bracket with a specific prescription, size & form. A set of wires are individually fabricated for the patient. CAD – CAM Lingual Systems Use of plaster mal-occlusion model & set-up model. Use of 3D scanners (intra-oral or model/ impression scanning) to produce a 3D digital model. Monitoring the set-up This data is transformed to produce the individual brackets & wires. Advantages of the CAD CAM system: 1. Since there is no need for composite base adaptations, the brackets are Low profile bracket that reduces patient discomfort during the adaptation phase. 2. Accurate – less finishing needs, control 3. Exact & easy direct rebonding in the event of bracket loss Disadvantages 1. Cost 2. Time & Dependency on the laboratory 3. Extra costs in case of bracket / wire lost eBrace specific features Fully programmed Brackets Optimal Control 1. Set-up 2. Bracket design Mesh Pad Base Rotation aids 6 individual upper jigs Prevention Transitional Brackets Bands Occlusal Pads No extra charge The 2nd Generation Bracket • Widen the anterior slot ; Easily control teeth rotation The 2nd Generation Bracket • Deepen the anterior slot ; the wire can be fully inserted into the slot that can control the torque better Digital setup—3shape Ortho-Analyzer TM • The comparison between malocclusion and ideal setup Incognito comments eBrace comments Gold Nickel allergy Non precious alloy Lower weight Mesh base Ad. in rebonding No contamination Full prescription in bracket Limited robot Simpler wires Wires need upgrading Smooth base Prescription in bracket & wire robot Limited doctor control Full doctor control Price Price Bands, brackets extra charged price No charge for bands, extra brackets price Bonding aids Prevent hook blockage 6 jigs Accurate easy rebonding CAD CAM individualized Self Ligating Systems Incognito – 3M Germany Harmony - AO eBrace SL - Riton The Self Ligating Bracket -May 2013 -Manipulation -Upper wing for easy elastics ligation -2nd “slot” Advantages of the self ligating systems 1. Less friction / better siding / faster treatment 2. less finishing needs due to better wire engagement 3. Easier & faster wire engagement 4. less chair-time Disadvantages of the self ligating systems 1. Manipulation – on finishing 2. The stability & resistance of the existing systems 3. Patient comfort –higher profile The Orthodontic Lingual treatment Case Selection Lingual Orthodontics is relatively easy in the following cases: Non-extraction cases – good facial pattern • Deep bite, Class I cases with mild crowding • Deep bite, Class I with spacing or diastema • Deep bite, mild Class II • Class II division 2 with retruded mandible Extraction cases • Class II, maxillary first, mandibular second bicuspid extraction • Class II, maxillary first bicuspid extraction • Mild bi-maxillary protrusion with four first bicuspid extraction • Class III tendency with deep bite relatively difficult in the following cases: • Surgical cases • Open bite cases, dolico-cephalics • Periodontal involvement with reduced bone level • Class III high angle case • Class II high angle cases • Severe Class II discrepancies • Cases with multiple restorative work • Short, abraded & irregular lingual tooth surfaces • Poor oral hygiene • Mutilated should be avoided in the following cases • Acute TMJ dysfunction • Unresolved periodontal problems • Inadaptable personality type Patient Evaluation & preparation: • Proper expectation understanding – esthetical & facial • Explanation of the specific nature of the lingual appliance • Identification of the specific gingival, tooth form, size & color problems • Aesthetic evaluation • Periodontal and Prosthetic evaluation • Personality Sarver 12/2004 AJODO J.Morley JADA 01.2001 Diagnosis considerations: ● General, with particular reference to esthetics ● Periodontal and gingival ● Dental, with particular reference to the presence of crowns and large restorations ● Dento-alveolar discrepancy ● 3D analysis dental / skeletal problems: Vertical, AP, transverse ● Surgical cases ● Pre-prosthetic cases 1. Records 2. Diagnosis • Skeletal and growth pattern • Dental analysis • Space analysis • Aesthetic evaluation • Periodontal and Prosthetic evaluation • TMJ evaluation • Personality 3. Case preparation - Periodontal initial preparation - Restorations and prosthesis: • Old amalgam restorations can be replaced with composite restorations. • Bridges can be separated to units, or used as one unit if not separated. • Root treated teeth should be prepared with posts and temporary crowns, permanent cement. • When transferring from expansive appliance to lingual, a retainer is needed to avoid inaccuracy of the model • Lingual tooth surfaces changes should be reformed when deep fosse or pronounced bulges are present. - Impression taking • use silicone (poly vinyl siloxane) accurate material. • Accuracy is important (2 step). Laboratory procedure The laboratory procedure allows individual adaptation of the brackets to each tooth. Laboratory instructions 1. consider treatment plan 2. consider side effects Teeth Consider changes M 41 42 0.2 43 0.2 D Teeth M D 0.1 32 0.2 33 0.2 0.2 35 0.2 0.2 0.2 Consider changes Consider changes Additional brackets accessories Active treatment • Chair side Indirect bonding • Banding • Extraction (timing is important) • Treatment Mechanics: Leveling, aligning, rotational control and bite opening Torque control Consolidation and Retraction (En masse retraction) Detailing and finishing Retention Follow-up documentation: photos, models, x-rays Lingual Orthodontics (Li) and Labial Orthodontics (La) biomechanical differences Bite plane effect - Anterior bite plate - Anterior teeth intrusion (!!!) – more bodily & less proclination - Posterior teeth extrusion can be avoided. - More intrusive effect on the lower incisors - age changes. IBD (inter-bracket distance) The IBD is 40% smaller then buccal Increase wire stiffness - X 3 times for 1st & 2nd order bends & - X1.5 times for the 3rd order bends Heavier forces in LO, more difficult to control rotations angulations & torque since activation range is reduced. Higher friction Reduce wire stiffness - Use of small diameter Nickel Titanium / heat activated wires - increasing the inter-bracket wire and arch perimeter: - small size brackets - ½ bracket, small attachment, - do not legate all brackets - use of individual bracket systems - chose the best system according to the case needs (2D / full prescription) Friction Multifactorial Bracket type & material, wire material & size, wire stiffness, play, archwire-bracket combination moment (binding), OH… Since the IBD is smaller, the wire stiffness in higher more friction & binding is incresed. Ligating mode: double over tie The point of force application & line of force relative to the center of resistance (CoR) Vertical Buccal – intrusive force will procline the teeth Lingual - more complicated. The effect cannot be accurately anticipated, since it depends on bracket position and initial tooth inclination. Up to a certain transitional degree of initial tooth inclination, intrusive force create retroclination or labial root moment, from this point on the moment will roll over and the tooth proclines The transitional point in which the pure intrusion occurs without proclination or retroclination moments was defined in a theoretical model as 200 (Geron et al 2004) - ??? Horizontal force labial and lingual - develop moments that tends to move the crown in the direction of force, and the root in the opposite direction. For retraction - moment tends to retrocline the incisors The size of the moment (retroclination) depends on the distance between the PF and CR (Moment = Force x Distance). d F When the teeth are proclined, the moments developed using lingual for retraction/ protraction forces are higher compared to buccal due to the larger moment arm, the incisors tends to retrocline/ procline more in lingual and it is more difficult to control the incisors torque during retraction. The more the tooth is proclined the higher the difference between moments created by lingual and buccal. Torque control: increase anterior torque: Use of high torque brackets / Laboratory G7 LBJ Add torque in wire Molar Intrusion canting of Occlusal Lingual Root Torque Anterior Extrusion The tongue spurs effect. Disadvantage of the lingual appliance – patient discomfort Advantage - Open bites, tongue habits - tongue education – more posterior position. Anchorage “Resistance to force to avoid movement / un desired movement” maximal “Gianelli” & “ Burstone”• Maximal • Moderate (50:50) • Minimal moderate minimal Anchorage Considerations Which tooth to extract? 1st / 2nd premolar? Esthetic consideration – adults, solutions Disarticulation En Masse retraction Takemoto value of molar anchorage in Lingual approach is higher… -Line of the retraction force closer to the CoR -Buccal root torque & disto-palatal rotation, cortical anchorage Buccal - sliding mechanics showed significantly more anchorage loss then in lingual. No difference in anchorage loss was found between first or second premolar extractions in cases treated with the lingual technique. Takemoto K: Anchorage control in lingual orthodontics,in Romano R (ed): Lingual Orthodontics. Hamilton, Canada, BC Decker, 1998, pp 75-82 Takemoto K: Lingual orthodontic extraction therapy.Clin Impressions 4(3):2-7, 1995 Anchorage Control in Lingual Orthodontics 1. 2. 3. 4. 5. 6. Molar tip back Bi-dimentional mechanics – wire / slot – friction reduction Posterior bite blocks Light forces Use of inter-maxillary elastics Add 2nd molar TAD TAD Treatment steps Leveling & alignment - Small diameter wires - Full engagement of the wires in the slot 1. Regular elastic tie 2. Double over tie 3. Still ligature Double over tie 4. Power tie 5. Power chain Space considerations - Non Extraction Cases 1. 2. 3. 4. IPR Advancement – loops – chair side / laboratory Crimpable stops Distalization. Maxillary arch expansion. Faster due to the disarticulation Less buccal tipping - Cetrifugical effect like QH & RPE / RME - tongue - Point of force application is closed to the center of resistance Rotations Retraction Torque control during retraction: - Use of horizontal slot - Rectangular wires on retraction / bi dimensional wires - Prescribing over-torque in the bracket - Reducing the retraction force. Side effects Bowing effect Deformation of the arch the vertical & horizontal dimensions: - Lateral open bite at premolar area - Extrusion of molars & incisors - buccal tipping of the lateral teeth. How to avoid (or treat) vertical and transverse bowing effect? 1. Use Stiffer wires (.016x.022 S.S) 2. Add 2nd molars 3. Compensating horizontal and vertical wire bending 4. Apply short-span forces (3 unit systems) 5. Do not connect chains to terminal molar 5. Add torque/ tip/ angulation (positioning / laboratory / wires) 6. Tube & bracket positioning 7. Add anchorage: palatal bars, Nance… 8. Loop mechanics Special clinical situations CL II increased over jet. - CL II aggravation due to bite opening - Sever proclination might increase. - After initial re3traction a upper incisor blockage by lower incisors – anchorage lost - Accentuated in cases with bone lost – apical CoR – increased “d” Use of posterior bite opening. Force vector labial to CoR Special clinical situations Deep Over bite The anterior bite opening & molar extrusion are beneficial - Deep bite + sever retroclination Aggravation of retroclination- force/CoR Bite opening & proclination first Special clinical situations Deep bite + large over-jet - No bite opening effect. - Retraction blockage - Anchorage lost Molar bite blocks are advised with the use of Cl II elastics for Mandibular advancement. Special clinical situations Open bite Correction of AOB - Molar intrusion and / or incisor extrusion and retroclination - Molar intrusion – TAD, bite blocks… - Myofunctional adaptation (?) CL III cases necessary to create four points of occlusal contact: Anterior unlocking Finishing • Most challenging and difficult stage of treatment. • In certain cases - more time and effort than to correct the major malocclusion. • Longer & more difficult then buccal Orthodontics • Better clinical judgment then buccal Difficulty due to: • Need of specific individual considerations. • Anatomy of the lingual surfaces. • Lingual mechanics. Need of specific individual considerations. Adults: Dental conditions - restorations, - missing teeth - abrasions Periodontal conditions - gingival heights System limitations - bracket positioning & O-G height - bracket repositioning - rebonding inaccuracy - need of laboratory assistance - costs ( “Sure-smile” ) Lingual biomechanics Requirements of 3D bends Short lingual anatomical crown Small IBD Step up + step in Step out + step down Lingual biomechanics Difficult movements: • Up-righting • Torque • Rotations Late bracket prescription expression Need for full wire engagement Specific ligation modes Adopt the MBT recommendation for 3 months expression Basic principals for Finishing 1. Try to avoid the side effects - Individualized systems - Positioning jigs - Anticipation: step-up, photos, prescription bracket positioning - Light forces (bowing, tip, rotations, retroclination…) Avoid the side effects Extraction case Ligature tie 6-7 Chain 6M-4 Avoid the side effects Extraction case Use of tubes on molars – not brackets !! Use buccal attachments 2 . Allow full prescription expression. Return to rectangular elastic wire (NT / CuNT) Full engagement of the wire In case of Extraction case – secure the arch with SS ligature wire to avoid space opening Bowing correction 3. Occlusion settling • • • • Includes correction of minor midline, A-P & vertical Using inter-maxillary elastics – in the different modes Lower arch is stabilized – rectangular SS / TMA wire Upper arch with full / sectional, small diameter round wire (014) 4. Finishing bends Chair side On model – photos can be added. Upper - 017X025 TMA Lower - 016 TMA (IBD) V-bend (tent bend)- incisor angulation Combined with expansion eBrace Cases Adult . CL II skeletal & dental. Mild retrognathic mandible. Moderate proclination of upper incisors. Strait retrognathic profile. Open Naso- labial angle 6 Treatment objectives: L & A by IPR. Remove buccal composite excess on tooth 21 for future laminate. No OJ change. 8 months Treatment Objectives: Upper only lateral expansion, IPR 2.8 mm in total 5 months in treatment Oct. 2012 15 months Feb. 2013 – 18 months Dr. Geron Silvia 4 months - 18.July 2011 7 months 9 months Dr Zhang Dr Lei Feifei 2011-02 2011-07 2011-08 2012-01 2011-02 2011-07 2011-08 2012-01 Dr. Wu Yuhai • Female, 35years old • Chief Complaint : midline deviation • Medical History: upper left bicuspid was extracted when orthodontic treatment was taken during adolescence. • Clinical Examination : skeletal class III , Class III relationship, lower first bicuspids missing, midline deviation, minor crowding in lower arch, upper arch constricted Dr. Wu Yuhai After bonding In progress (6 months) 12 months 8 March 2013 – 9 months after bonding Last 2 months 3dsdentsup@gmail.com +972-54-2666440 E-Brace Lab order form Patient (Surname) ___Adi_ (First name) ___Shukrun____ Orthodontist_____Mazor ___ Address Contact (Tel.) (Fax) (Email) Date and time of bonding Please fully complete the treatment plan Please mark here for laboratory wire selection (copy / paste Set of archwire (6) Wires required diameter (please tick) 012Φ Ex Ex 014Φ SE Ni-Ti this mark to select) Maxillary Mandible arch arch 016Φ 016×022 Φ 017×025 Φ 016 Φ Steel IPR 016×022 Φ 018×025 Φ 016 Φ TMA 016X022 Φ 017×025 Φ 018×025 Φ Ex Materials sent by the doctor Ex Silicone impressions Intra-oral & For an ex-case please indicate space closure or not Please fill in: Ex= to be extracted; B= bracket; casted T=tube; ring=circle tooth; H= X= missing; leash hook; occlusal surface=shade in Bracket Series: Pease Copy/paste those elements as required. pad extra-oral By -mail photos plaster model X-ray By e-mail picture Remarks: - Only upper arch - 15,25,35,45 extraction - Upper expansion – PLS prepare expanded arches - 15,25- esthetic composite pontics - Please setup the lower model. It is recommended to print, fill in and attached this lab form to the impressions. 9 months (2 months in Thailand…) 1 month Half bracket 3 month 5 month Time for the new bracket on 22 3 months