WHY Lingual Orthodontics?

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1 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

2 WHY Lingual Orthodontics?

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4 More adults - Invisible - Not interfere with their everyday function & physical appearance. What can we offer them?

5 What alternatives: Ceramic brackets Clear Aligners

6 Lingual Orthodontics

7 History of L.O 1841 Pierre Joachim Lefoulon lingual arch for expansion & alignment

8 1975 Craven Kurz- USA Used plastic brackets easy to adapt to anterior lingual surface. Only Invisible, please -Debondings -Uncomfortable

9 Modern lingual appliance K. Fujita Japan 1978 introduced his method. 3 piece bracket 3 slots: V, H, Oc.

10 Commercial interest Ormco (Kurz) 1 st generation (1977) 7 th generation(1990) 1 st 2 nd - add hooks 3 rd - add hooks on molars 4 th - profile change for easier wire insertion 5 th - bite plane, more torque, accessory tube 6 th - longer hooks 7 th - romboid bite plan to increase IBD, PM longer slot

11 The American Lingual Orthodontic Association 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

12 France Fontenelle 1978 first publish Fillion Didier research, publish, lecture. ESLO + Alaine Decker Paris V - lingual program Italy Massimo Ronchin (1 st president of ESLO) developed in 1994 the L- SLB (Forestadent), 2D lingual brackets- MTM Giusepe Scuzzo (3 rd ) 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 the first study cub (Kurz, Laughlin, Creekmore, Wildman, Scuzzo, Fillion )

13 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

14 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)

15 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

16 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 2 nd order bends are required.

17 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.

18 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.

19 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.

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21 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.

22 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.

23 Simplified Technique - Ormco, STb Developed for the STb brackets. Direct positioning on the malocclusion model: anterior brackets at mm from incisal, canines at 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 mm mm center

24 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.

25 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

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27 Advantages & Disadvantages of Lingual Orthodontics

28 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).

29 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

30 Maxillary molar distalization & expansion. More bodily CoR is more palatal to the long axis

31 Basic Lingual Approaches & systems 1. Anterior bite plane 2. Wide base 3. Hooks The conventional lingual bracket 1 2 3

32 Vertical slot tip control - posterior teeth Horizontal slot torque control anterior teeth Horizontal slot Vertical slot

33 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

34 Ormco 7 th 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.

35 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.

36 ORG ORJ- Romano-Geron Mid form - 7 th & STb

37 American Orthodontics Small, narrow and smooth Horizontal slot.020x.020 Auxiliary vertical slot

38 STb (ORMCO) (Scuzzo-Takemoto brackets)

39 Forestadent 2D, 3D, SL Low Profile

40 Adenta - Evolution a self-ligating lingual bracket Modified Hiro system

41 GAC Innovation-L self ligating brackets

42 Phantom

43 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

44 New Pre-fabricated Bi-dimensional wires. Pre-fabricated double offset SW

45 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)

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47 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.

48 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.

49 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.

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51 Monitoring the set-up

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54 This data is transformed to produce the individual brackets & wires.

55 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

56 ebrace specific features

57 Fully programmed Brackets

58 1. Set-up 2. Bracket design Optimal Control

59 Mesh Pad Base

60 Rotation aids

61 6 individual upper jigs

62 Prevention

63 Transitional Brackets Bands Occlusal Pads No extra charge

64 The 2 nd Generation Bracket Widen the anterior slot ; Easily control teeth rotation

65 The 2 nd Generation Bracket Deepen the anterior slot ; the wire can be fully inserted into the slot that can control the torque better

66 Digital setup 3shape Ortho-Analyzer TM

67 The comparison between malocclusion and ideal setup

68 Incognito comments ebrace comments Gold Nickel allergy Non precious alloy Lower weight Smooth base Mesh base Ad. in rebonding No contamination Prescription in bracket & wire robot Full prescription in bracket Limited robot Simpler wires Wires need upgrading 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

69 CAD CAM individualized Self Ligating Systems

70 Incognito 3M Germany

71 Harmony - AO

72 ebrace SL - Riton The Self Ligating Bracket -May Manipulation -Upper wing for easy elastics ligation -2 nd slot

73 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

74 Disadvantages of the self ligating systems 1. Manipulation on finishing 2. The stability & resistance of the existing systems 3. Patient comfort higher profile

75 The Orthodontic Lingual treatment

76 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

77 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

78 should be avoided in the following cases Acute TMJ dysfunction Unresolved periodontal problems Inadaptable personality type

79 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

80 Aesthetic evaluation Periodontal and Prosthetic evaluation Personality Sarver 12/2004 AJODO J.Morley JADA

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83 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

84 1. Records

85 2. Diagnosis Skeletal and growth pattern Dental analysis Space analysis Aesthetic evaluation Periodontal and Prosthetic evaluation TMJ evaluation Personality

86 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).

87 Laboratory procedure The laboratory procedure allows individual adaptation of the brackets to each tooth.

88 Laboratory instructions 1. consider treatment plan 2. consider side effects

89 Consider changes Teeth M D Teeth M D

90 Consider changes

91 Consider changes

92 Additional brackets accessories

93 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

94 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.

95 IBD (inter-bracket distance) The IBD is 40% smaller then buccal Increase wire stiffness - X 3 times for 1 st & 2 nd order bends & - X1.5 times for the 3 rd order bends Heavier forces in LO, more difficult to control rotations angulations & torque since activation range is reduced. Higher friction

96 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)

97 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

98 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.

99 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 20 0 (Geron et al 2004) -???

100 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

101 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.

102 Torque control: increase anterior torque: Use of high torque brackets / Laboratory LBJ G7 Add torque in wire Molar Intrusion canting of Occlusal Anterior Extrusion Lingual Root Torque

103 The tongue spurs effect. Disadvantage of the lingual appliance patient discomfort Advantage - Open bites, tongue habits - tongue education more posterior position.

104 Anchorage Resistance to force to avoid movement / un desired movement maximal Gianelli & Burstone - Maximal Moderate (50:50) Minimal moderate minimal

105 Anchorage Considerations Which tooth to extract? 1 st / 2 nd premolar? Esthetic consideration adults, solutions Disarticulation En Masse retraction

106 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 Takemoto K: Lingual orthodontic extraction therapy.clin Impressions 4(3):2-7, 1995

107 Anchorage Control in Lingual Orthodontics 1. Molar tip back 2. Bi-dimentional mechanics wire / slot friction reduction 3. Posterior bite blocks 4. Light forces 5. Use of inter-maxillary elastics 6. Add 2 nd molar

108 TAD

109 TAD

110 Treatment steps

111 Leveling & alignment

112 - 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

113 Space considerations - Non Extraction Cases 1. IPR 2. Advancement loops chair side / laboratory 3. Crimpable stops 4. Distalization.

114 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

115 Rotations

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118 Retraction

119 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.

120 Side effects

121 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.

122 How to avoid (or treat) vertical and transverse bowing effect? 1. Use Stiffer wires (.016x.022 S.S) 2. Add 2 nd molars 3. Compensating horizontal and vertical wire bending 4. Apply short-span forces (3 unit systems) 5. Do not connect chains to terminal molar

123 5. Add torque/ tip/ angulation (positioning / laboratory / wires) 6. Tube & bracket positioning 7. Add anchorage: palatal bars, Nance 8. Loop mechanics

124 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

125 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

126 Deep bite + large over-jet - No bite opening effect. - Retraction blockage - Anchorage lost Special clinical situations Molar bite blocks are advised with the use of Cl II elastics for Mandibular advancement.

127 Special clinical situations Open bite Correction of AOB - Molar intrusion and / or incisor extrusion and retroclination - Molar intrusion TAD, bite blocks - Myofunctional adaptation (?)

128 CL III cases necessary to create four points of occlusal contact: Anterior unlocking

129 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.

130 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 )

131 Requirements of 3D bends Short lingual anatomical crown Small IBD Lingual biomechanics Step up + step in Step out + step down

132 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

133 1. Try to avoid the side effects Basic principals for Finishing - Individualized systems - Positioning jigs - Anticipation: step-up, photos, prescription bracket positioning - Light forces (bowing, tip, rotations, retroclination )

134 Avoid the side effects Extraction case Ligature tie 6-7 Chain 6M-4

135 Avoid the side effects Extraction case Use of tubes on molars not brackets!! Use buccal attachments

136 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

137 Bowing correction

138 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)

139 Chair side On model photos can be added. Upper - 017X025 TMA Lower TMA (IBD) 4. Finishing bends

140 V-bend (tent bend)- incisor angulation Combined with expansion

141 ebrace Cases

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144 Adult. CL II skeletal & dental. Mild retrognathic mandible. Moderate proclination of upper incisors. Strait retrognathic profile. Open Naso- labial angle

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147 Treatment objectives: L & A by IPR. Remove buccal composite excess on tooth 21 for future laminate. No OJ change.

148 8 months

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163 Treatment Objectives: Upper only lateral expansion, IPR 2.8 mm in total

164 5 months in treatment

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173 Oct months

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177 Feb months

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179 Dr. Geron Silvia

180 4 months - 18.July 2011

181 7 months

182 9 months

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184 Dr Zhang

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186 Dr Lei Feifei

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188 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

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192 Dr. Wu Yuhai

193 After bonding

194 In progress (6 months)

195 12 months

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200 8 March months after bonding

201 Last 2 months

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204 E-Brace Lab order form tient (Surname) Adi_ (First name) Shukrun Orthodontist Mazor dress ontact (Tel.) (Fax) ( ) ate and time of bonding ease fully complete the treatment plan ease mark here for laboratory wire selection Set of archwire (6) (copy / paste this mark to select) Ex IPR Ex Wires required (please tick) SE Ni-Ti Steel TMA diameter 012Φ 014Φ 016Φ Φ Φ Maxillary arch 016 Φ Φ Φ 016 Φ 016X022 Φ Φ Φ Mandible arch Ex Ex Materials sent by the doctor Silicone impressions plaster model Intra-oral & X-ray For an ex-case please indicate space closure or not extra-oral By -mail By picture Please fill in: E x = to be extracted; X= missing; photos B= bracket; T=tube; H= leash hook; Remarks: casted ring=circle tooth; occlusal pad - Only upper arch surface=shade in - 15,25,35,45 extraction Bracket Series: - Upper expansion PLS prepare expanded arches Pease Copy/paste those elements as required. - 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.

205 9 months (2 months in Thailand )

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208 Half bracket 1 month

209 3 month

210 5 month

211 Time for the new bracket on 22

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213 3 months

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