2018/5/1. Invisible orthodontic appliances: clear aligner vs. individual lingual system. Treatment of bimaxillary protrusion.

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1 Outline Invisible orthodontic appliances: clear aligner vs. individual lingual system Treatment of bimaxillary protrusion 1. Two types of invisible orthodontics 2. Bimaxillary Protrusion (BP) 3. Treatment of BP with Lingual Appliances ( ebrace,china) 4. Treatment of BP with Clear Aligners (Invisalign G6, USA & Angelalign A7, China) 5. Clear aligner VS. Individual lingual appliance Invisible Orthodontics The current two types of invisible orthodontics In recent years, invisible orthodontics has been increasingly popular Popularity [1] Clear Aligner(CA) [1]Align Technology, Inc. Q4 and Year End 2017 Financial Results Bimaxillary Protrusion(BP) Treatment of BP Extraction of four premolars Retraction of anterior teeth with enhanced anchorage Protrusive upper and lower anterior teeth Class I or nearly Class I molar relationship Normal occlusion but dissatisfactory convex profile 1

2 Treatment of BP with LA Individual LA Lingual appliances have been applied to treat BP for 20 years Effective for levelling and enhanced posterior anchorage High efficiency for space closure and short duration ebrace(china) CAD/CAM Conventional Self-ligating brackets [1] Tai K, Park J H, Tanino M, et al. J Clin Orthod, 2012,46(12): , 754. [2] Tamamura N, Kuroda S, Sugawara Y, et al. The Angle Orthodontist, 2009,79(3): [3] Kawakami M, Miyawaki S, Noguchi H, et al. Angle Orthod, 2004,74(5): [4] Kurz C. Am J Orthod Dentofacial Orthop, 1997,112(4): [5] Jing Xuan, Wu Xiuping, Wang Jun. International J Stomatology, 2018,45(1): Straight or bended archwire Maxillary bite plate Personalized designs Case Report F, 21Y; CC: protrusive lips 2

3 Problem List Angle Cl I Skeletal Cl I, average angle Bimaxillary protrusion Moderate crowding Lower midline shifts to the left Impacted 38,48 Tx Plan Individual lingual appliance (ebrace) Set-up ebrace (China) Extract 14, 24, 35, 45 Tx 1 Mo Tx 3 Mo 3

4 Tx 5 Mo Tx 12 Mo Tx 14 Mo Tx 15 Mo Tx 17 Mo 有没有 debonding 的结束合面像? 如果没有, 可以不放合面像 Tx 17 Mo 4

5 Pre-tx Good match Post-tx Set-up Case Summary Case Report The ebrace individual lingual appliance is highly efficient for treatment of BP through anterior retraction after extraction TADs are used only for the upper, and we have extracted the lower 5s instead of 4s since the lower molars have very strong anchorage F, 31Y; CC: protrusive lips 5

6 Mesurement Normal SNA ( ) SNB ( ) ANB ( ) SN-MP ( ) S-Go/N-Me (%) U1-L1 ( ) U1-SN ( ) FMIA ( ) UL-E (mm) LL-E (mm) Skeletal ClⅡ High angle Problem List Problem List Angle clⅡ,sub Problem List Moderate crowding 6

7 Problem List Lower midline shifts to the right Tx Plan Extract 15, 25, 35 Finish with full Cl II on the right and Cl I on the left Difficulty: torque control of upper incisors Key point : Ask for 7 additional labial crown torque for the upper incisors Tx Plan Set-up ebrace (China) Tx 4 Mo Tx 7 Mo 7

8 Tx 7 Mo Tx 13 Mo F M Labial crown torque Tx 13 Mo Finish 18 Mo Finish 18 Mo Finish 18 Mo 8

9 Finish 18 Mo Retention 6 Mo Retention 6 Mo Improved chin curvature and profile! 9

10 Case Summary Treatment of BP with CA This is not a BP but a skeletal Cl II camouflage case, which is more difficult with higher demand for the torque control of upper incisors The individual LA itself is fairly good for anterior torque control, thanks to the ribbon archwire Additional pre-torque can be added to the upper incisors in the set-up if necessary Only a small number of BP cases treated with clear aligners has been reported According to our experiences The less crowding, the more difficult, due to more sagittal teeth movement needed The more molar mesialization, the more difficult [1] Giancotti A, Greco M, Mampieri G. Prog Orthod, 2006,7(1): [2] Choi N, Park Y, Jo Y, et al. American Journal of Orthodontics and Dentofacial Orthopedics, 2009,135(5): [3] Yutong P, Jie T, et al. Journal of Practical Stomatology, 2012,28(05): Invisalign G6 Invisalign G6 Invisalign (Align Technology, USA) has developed the G6 scheme for premolar extraction and maximum anchorage cases, with molar mesialization less than 2mm G6 is supposed to facilitate bodily molar mesialization with optimized attachments and staging Multi-teeth Unit Optimal anchorage attachments Optimal retraction attachments Aligner pre-anchorage SmartForce SmartStage Case Report F, 26Y, CC: protrusive lips 10

11 Problem List Angle ClⅡ Skeletal ClⅡ,high angle Bimaxillary protrusion Severe crowding Excessive overjet Impacted 38&48 Tx Plan Extract 14, 24, 34&44 Retract front teeth to reduce lip protrusion Invisalign, G6 Tx 6 Mo G6 attachments not applicable for 26&27 due to short crowns; therefore conventional attachments placed instead 11

12 Tx 10 Mo Tx 16 Mo 18 Mo (R0 Finish) Tx 18 Mo Going on with refinement Tx 18 Mo 12

13 Case Summary When treating BP with the Invisalign G6, molars are supposed to be mesialized less than 2mm; therefore, TADs are usually needed for the upper arch Even with G6, molar tilting is almost unavoidable, which requires correction in the refinement stage; therefore, the whole Tx duration is usually more than 2.5 years, longer than LA Angelalign A7 Angelalign (China) has also introduced the A7 scheme for treatment of BP cases with 4 premolars extraction and maximum anchorage A7 uses vertical rectangular attachments on posterior teeth, characterized by dual vertical rectangular attachments(dva) on first molars to facilitate bodily mesialization Anchorage control Angelalign A7 Torque control Bodily movement of canine Vertical control of posterior teeth Dual vertical rectangular attachments(dva) greater moment Pre-anchorage (molar distal tipping first before mesialization) 13

14 Case Report F, 32Y; CC:protrusive profile measurement normal SNA ( ) 83.1± SNB ( ) 79.7± ANB ( ) 3.5±2-2.7 SN-MP ( ) 32.9± S-Go/N-Me (%) 65.9± U1-L1 ( ) 127.0± U1-NA(mm) 4.0±2 9.1 U1-SN ( ) 104.6± L1-NB(mm) 4.0±2 9.5 L1-MP( ) 90.0± FMA( ) 25.0± FMIA ( ) 57.0± UL-E (mm) 2.0±2 2.0 LL-E (mm) 3.0±2 4.7 Problem List Problem List Angle Cl I Skeletal Class III Low angle Horizontal growth pattern 14

15 Tx Plan Extract 14, 24, 34& 44 Retract the anterior teeth to reduce lip protrusion Angelalign, A7 Tx 3 Mo Tx 8 Mo Tx 15 Mo 21 Mo (R0 finish) Going on with refinement 15

16 21 Mo (R0 finish) 21 Mo (R0 finish) 21 Mo (R0 finish) measurement normal Pre-tx R1 SNA ( ) 83.1± SNB ( ) 79.7± ANB ( ) 3.5± SN-MP ( ) 32.9± S-Go/N-Me (%) 65.9± U1-L1 ( ) 127.0± U1-NA(mm) 4.0± U1-SN ( ) 104.6± L1-NB(mm) 4.0± L1-MP( ) 90.0± FMA( ) 25.0± FMIA ( ) 57.0± UL-E (mm) 2.0± LL-E (mm) 3.0± Case Summary When treating BP with Angelalign A7, TADs are still needed for the upper arch if maximum anchorage is needed The results and duration for treating BP extraction cases using Angelalign A7 or Invisalign G6 are similar Different from Invisalign G6 s optimized attachments, Angelalign A7 mainly uses conventional attachments, which may be more reliable however less comfortable Share in common Clear aligner VS. Individual lingual appliance Esthetic The outstanding advantage of these two types of appliances lies in INVISIBLE Digital Customized, with visible and more accurate outcomes [1] Nedwed V, Miethke RR. Motivation, J Orofac Orthop, 2005, 66(2): [2] Meier B, Wiemer KB, Miethke RR. J Orofac Orthop, 2003,64(5): [3] Fritz U, Diedrich P, Wiechmann D. J Orofac Orthop, 2002, 63(3):

17 Differences Clear aligner VS. Individual lingual appliance I. Almost VS. Complete invisible CA is less invisible compared with LA, due to attachments and the possible white spot lesions on the labial surface However, it seems that CA can also meet the esthetic requirements of the majority of patients. II. Efficacy of tooth movement CA molar distalization(88%), intrusion(33%-37%), torque(49%-51%), rotation(19%-43%) LA High efficacy in maxillary expansion, bite-opening, en-masse retraction of anterior teeth LA is more efficient for treating BP extraction cases [1] van der Veen MH, Attin R, Schwestka-Polly R, et al. Eur J Oral Sci, 2010, 118(3): [1]Rossini G, Parrini S, Castroflorio T, et al. Angle Orthod, 2015, 85(5): [2] George RD, Hirani S. J Orthod, 2013, 40 Suppl 1: S8-13. III. Quality of Life CA has a higher quality of life Pain Speech Mastication Clear aligner Short recovery No effect No effect Lingual appliance More severe Long recovery Negative effect Negative effect IV. Periodontal health Periodontal health during orthodontic treatment mainly depends on oral hygienic condition LA is hard for cleaning and therefore affects periodontal health CA is removable and much easier for cleaning Direct comparison of CA vs. LA: CA wins! CA is a better choice for patients with periodontal or oral hygiene problems [1]Shalish M, Cooper-Kazaz R, Ivgi I, et al. Eur J Orthod, 2012, 34(6): [2] Khattab TZ, Farah H, Al-Sabbagh R, et al..angle Orthod, 2013, 83(3): [1]Talic NF.. Saudi Dent J. 2011,23(2): [2]Lombardo L, et al. Prog Orthod. 2013;14:28. [3] Miethke RR, Brauner K. J Orofac Orthop. 2007,68(3): V. Temporomandibular joints CA is a kind of splint appliance with certain thickness. Bite plates of front teeth brackets in LA can separate the upper and lower teeth and eliminate occlusal interferences Both may have beneficial effects on TMJ problems VI. For orthognathic surgery Both can be used for orthognathic surgery cases The labial surface of teeth may need temporary bonding of brackets or buttons for post-surgery elastics, which requires informed consent from the patient when choosing to use CA or LA 17

18 VII. Duration, chair-side time and visit frequency LA seems to have a shorter average duration compared with CA CA cases have an obvious reduction in chair-side time and visit frequency For who want to finish earlier, LA is suggested; for who cannot visit monthly, CA is better VIII. Compliance The treatment effect and duration of CA largely rely on the patients compliance, since the aligners are removable. Invisalign teenage aligners have compliance indicators, though the validity of which is doubtful CA has higher demand for the patient s compliance [1] Gu J, Tang JS, Skulski B, et al. Am J Orthod Dentofacial Orthop, 2017, 151(2): [2] Buschang PH, Shaw SG, Ross M, et al. Angle Orthod, 2014, 84(3): [1]Tuncay OC, Bowman SJ, Nicozisis JL, et al. J Clin Orthod. 2009,43(4): Summary IX. Experience requirement For easy cases, CA is less technique sensitive compared with LA However for difficult cases, special training and experiences are required for the CA orthodontists, since it s a totally different system from the fixed appliances CA is much more difficult than it looks like Individual lingual orthodontics is powerful and mature to treat almost all types of malocclusions with high efficiency, especially for the bimaxillary protrusion extraction cases The treatment results for BP extraction cases using clear aligners are acceptable, though not so efficient, and this technique is evolving everyday with promising future 18