recent advances in orthodontics

Recent advances in orthodontics

1. Recent advances in Orthodontics B y Dr. Ashok kumar A MDS

2. CONTENTS Introduction Recent advances in Brackets Recent advances in Bonding materials Recent advances in Orthodontic wire Recent advances in Software Recent advances in Digital orthodontics Recent advances in appliances Recent advances in robotics Recent advances in Bioengineering Conclusion References

3. Introduction There has been tremendous progress in orthodontics since Edward Angle first popularised the fixed orthodontic appliance. Recent years have seen an increased demand for orthodontic treatment from both adolescents and adults , and in addition , patient and clinician expectations of treatment outcomes also continue to rise . Technological & material advancements in orthodontics has made possible a constant improvement in the quality of orthodontic treatment ultimately benefiting the patient.

4. Technological infusions that have been game changers in orthodontics Up in the Air :Orthodontic technology unplugged! 2017 APOS Trends in Orthodontics

5. Recent advances in Brackets

6. Fabrication of orthodontic brackets A new material containing hard alumina nanoparticles embedded in polysulfone was introduced in year 2012 (UC3M) for making orthodontic brackets. The rigidity of the material increases the strength of the brackets & also reduces frictional and mechanical resistance of the brackets to orthodontic wires along with maintaining the transparency of the brackets. Coating with NPs also improve their properties like: Titanium dioxide because of its photocatalytic properties Ni-P -WS2 nanoparticles to Reduce friction. Zno and Cuo nanoparticles for antibacterial properties 6

7. Smart brackets with nanomechanical sensors Knowledge of the 3D force-moment systems applied for OTM is important for the predictability of the course of tooth movement & reduction of traumatic side effects. Nanomechanical sensors can be fabricated and be incorporated into the base of orthodontic brackets in order to provide real-time feedback about the applied orthodontic forces. Allows the orthodontist to adjust the applied force to be within biological range to efficiently move teeth with minimal side effects. Smart bracket for multidimensional force and moment measurement. J Dent Res 86(1):73–78 Lapaki et al 2007 - “smart” bracket 7

8. APC –Adhesive Coated Appliance System The only orthodontic bonding system that precoats each bracket with adhesive.

9. Wild Smiles braces Dr. Clarke Stevens , a practicing orthodontist from Omaha, wanted kids to be able to express themselves with their braces. Colored bands were already available, so he decided to focus on the brackets that attach to the teeth, and WildSmiles braces were the result. Different bracket shapes can be combined, and colored bands can be added, giving child the ability to be creative with their smile.

10. Self ligating bracket Decreased plaque accumulation compared to conventional brackets & decreased friction between bracket and arch wire Decreased chair time for arch wire changes U se of light forces & Possibly faster tooth movement

11. Recent advances in Bonding materials

12. 6 th Generation –Self etching primer Eliminate wash & dry step after etching , so collagen collapse by air drying is avoided. H ydrophilic primers- Ortho Solo, Assure, MIP bond in a slightly wet environment . 7 th Generation - They are first , No mix self etch adhesive provided in single container combining all steps –Etching , priming , adhesion in bonding . 8 th Generation – Voco America introduced Futurabond DC ( nano -sized filler -12 nm that increases penetration of resin monomer & hybrid layer thickness )

13. Color Change Adhesive Color changing adhesive for enhanced bracket positioning and flash clean-up One of the most advantage of these CCAs is visibility of any adhesive remnant at bracket seating as well as identifiable cleanup of adhesive remnants after debonding

14. Nanocomposites And Nanoionomers Nanoparticles of reduced size are being used as fillers to reduce polymerization shrinkage and to improve the mechanical properties of strength . Uysal et al (2010) - evaluated the bond strength of nanocomposites and nanoionomers shown that these nanomaterials may be suitable for bonding in orthodontics as they fulfill the shear bond strength ranges for clinical acceptability Types of fillers: Nanoclusters Nanoparticles Silica nanosized filler Titanium dioxide and Nano zirconia Techniques Flame pyrolysis , Flame spray pyrolysis , Sol–gel processes. 14

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16. Recent advances in Orthodontic wire

17. Copper NiTi alloy wires I ntroduced by Rohit Sachdeva and Suchio Miuasaki in 1994. This alloy contains 50 % -60% Of copper and 0.2%-0.5% chromium , in addition to Ni- Ti added to bring down the TTR to oral temperature . Copper is added to enhance the thermal properties of a nickel-titanium alloy. Super cable –Hanson 1993 - superelastic NiTi coaxial wire Seven Niti strands woven together in a long, gentle spiral to maximize flexibility and minimise force delivery This wire was specially developed to be used with SPEED self-ligating bracket sysrem .

18. Nickel-free austenitic SS & TMA Wires The steel is alloyed with 15%- 18% chromium, 3%- 4% molybdenum, 10% -14% manganese and about 0.9% nitrogen to compensate for the nickel. These wires are available as a single-, triple- or six-strand SS wires and TMA (Connecticut New Arch ,CNA ) arches , for example Noninium or Rematitan wires by Dentauram Titanium-niobium-aluminium ( Ti - Nb -Al) alloy It has the best mechanical performance among these nickel-free shape memory and superelastic alloys , was developed as a result of advances in processing technology. The Ti - Nb -Al wires can be used as a substitute for Ni- Ti wires. The Ti - Nb -Al expansion spring exerted lighter and continuous force and facilitated safe and efficient tooth movement .

19. Bioforce archwire S uperelastic shape memory nickel titanium wire that provides gradually increasing forces from anterior ( Light force to incisor & canines , moderate forces to bicuspids) to posterior segment ( Molars- Physiologic Heavy forces), all within one archwire . By ion beam implantation process , nitrogen replaces nickel on the top and changes the surface to titanium nitride. BioForce wires with Ion Cuard result in a significant reduction in friction during tooth movement.

20. Dual flex archwire The Dual Flex-l : It consists of an anterior section made of 0.016-in. round titanal and a posrerior section made of 0.016-in . round steel The Dual Flex-2 : It consists of a flexible front segment composed of a 0.016 x 0.022-in. rectangular titanal and a rigid posterior segment of round 0.018-in. steel The Dual Flex-3 : It consists of a flexible anterior part of a 0.017 X 0.025-in. titanal rectangular wire and a posterior part of 0.018 square steel wire . The Dual Flex-2 and 3 wires provide anterior anchorage and control molar rotation during the closure of posterior spaces and initiate considerable torque in the anterior segment.

21. Optiflex wires Talass introduced the first optiflex wire ( Ormco,USA ) to combine optimum mechanical properties with a highly aesthetic appearance. Plastic-coated NiTi Plastic covered, tooth coloured superelastic nickel-titanium archwires are available as Nitanium (Tooth Tone ). It is claimed to have lower friction and blends with natural dentition as well as ceramic, plastic and composite brackets. It is stain and cracks resistant.

22. Marsenol - Tooth colored Nickel Titanium wire coated with an elastomeric poly tetra fluroethyl emulsion exhibiting all the same working characteristics of an uncoated super elastic Nickel Titanium wire, manufactured by Glenroe technologies Fiber reinforced composite arch wires - fabricated using a procedure called pultrusion . Fiber bundles are pulled through an extruder, in which they are wetted with a monomer resin & then cured with heat and pressure resulting in polymerization . Circular or rectangular wires are formed during curing. This may be shaped into a different morphology by further curing, a process known as beta staging . Property - High elastic recovery, high tensile strength, low weight, excellent formability, excellent esthetics because of their translucency

23. Fabrication of Hollow Wires Spherical NiTi particles are coated over a textile or a polymer fiber via electrospinning . Then, the fiber is removed from inside thus producing a hollow wire . Advantage : Possibly reducing the material needed for the wire production. They may deliver lighter and more continuous force. The bending properties can be customized by inserting another wire into the hollow core. NiTi /Ni-TiO2 nanoparticles - ultrasonic spray pyrolysis (USP). Synthesis of NiTi /Ni-TiO2 composite nanoparticles via Ultrasonic Spray Pyrolysis . Materials & Technology Majeric et al. (2015) 23

24. Shape memory polymers Carbon Nanotubes or Nanofibers & organic-exfoliated Nanoclay are used as fillers. SMPs materials have the ability to memorize a macroscopic equilibrium shape and then be manipulated and fixed to a temporary shape under specific conditions of temperature and stress. Polymers activated by the body temp or by light ( photoactive nanoparticles ) . In addition, the SMP materials are clear, colourable , and stain resistant , providing the patient a more aesthetically appealing. Gunes S and Jana C. “Shape memory polymers and their nanocomposites : a review of science and technology of new multifunctional materials”. Journal of Nanoscience and Nanotechnology(2008) 24

25. Recent advances in Software

26. Orthodontic apps for smartphones The World of Orthodontic apps. Gupta et al APOS Trends Orthod 2017;7:73-9.

27. Orthodontic Apps

28. Patient Apps

29. Artificial intelligence and Machine learning AI as a science is very broad and encompasses various fields, including reasoning, natural language processing, planning, and machine learning (ML) Work in AI started back in 1943 ,but it was not until 1956 that the term “Artificial intelligence” was first used during a conference held at dartmouth college. A few years later, the term “machine learning” was officially applied to a checkers-playing program, considered one of the first successful self-learning tools. ML is not intended to mimic human behavior ,it supplements human intelligence by performing tasks that are beyond human capabilities Applications of artificial intelligence and machine learning in orthodontics Saeed N. Asiri et AL APOS Trends in Orthodontics2020

30. ML FOR DIAGNOSIS AND ORTHODONTIC TREATMENT PLANNING Extraction decision making predicting the extraction decision 80% (Wang et al 2010) and 93% (Jung SK et al 2016, Tang T et al 2019 (Anchorage requirement – 83 % ) 5–15% better accuracy of landmark detection with ML ( Leonardi et al 2008) Determining the growth status of patients ( Buschang PH et al 2017) Overlook diagnosing a lesion, tumor & canine impaction by OPG , lateral ceph ( Laurenziello M et al 2017) & CBCT ( Yilmaz et al 2017 ) Predicting the size of unerupted teeth ( Moghimi S, et al 2017) To determine the forces needed to align teeth ( Omran LN, et al 2018) Applications of artificial intelligence and machine learning in orthodontics Saeed N. Asiri et AL APOS Trends in Orthodontics2020

31. U sed to predict the change in lip curvature after orthodontic treatment with or without extractions. (Nanda SB et al 2017) Predictions of treatment outcomes in Class II and Class III patients ( Zarei A et al 2006) To classify patients craniofacial growth as either normal or abnormal (Perez SV et al 2016) Scope and performance of artificial intelligence technology in orthodontic diagnosis, treatment planning, and clinical decision-making - A systematic review

32. Recent advances in Digital orthodontics

33. It started to make its way into dental and orthodontic offices with the introduction of computerized scheduling in the 1974 . In last three decades most offices have now become paperless , digital photography and 3D radiography & intraoral scans To perform virtual treatment planning as well as translate the plans into treatment execution with digitally driven appliance and placement using various CAD/CAM techniques , indirect bonding trays and also custom made brackets & to robotically bent wires. Digital technology in orthodontics

34. Digital and computerised cephalometrics Robert Murray Ricketts (father of computerised orthodontics) spent a significant time in the development of computerised cephalometric systems , integration of growth prediction data and visual treatment objectives (VTO). Digital cephalometric systems that were developed in 1970s-1980s used 'Disc Operating Systems' (DOS) , later it was upgraded . Digital Cephalometrics - Computerised Cephalometrics Method of image acquisition Charge Coupled Device (CCD) or Complemenrary metaloxide semiconductor (CMOS) Digital radiography ( dR ) Photostimulable phosphor plate (PSP) Computed radiography (CR) Direct Indirect

35. 3D Skeletal imaging – CT & CBCT The first CT scanner was invented by Sir Godfrey N.Hounsfield in 1967. Xray tube & detector scan the skull image slice by slice of same thickness in axial direction from head to neck & each slice is stacked over one another in an orderly manner will give us the 3D image of the skull. To detect impacted teeth and oral abnormalities Airway & Facial analysis Assessment of alveolar bone height & volume TMJ morphology Lateral and frontal Ceph views Skeletal views & 3D review of dentition

36. 3D cephalometric analysis The first 3D cephalometric analysis was introduced by parket al. in 2006 Software tools for 3D evaluation Mimics (Materialize Co., Belgium) Dolphin (Dolphin Imaging Systems) AMIM (Mercury Computer Sys. Germany) Vitrea (Vital Images Inc.,Plymouth , MN) Maxilim (Medicim, Sint-Nikaas, Belgium) Anatomage (San Iose , CA)

37. Cephalometrics without X-rays Sonic digitisation is the process of digitisation of face/skull without making the cephalogram . The system uses sound waves to record the position of a landmark. This concept was first introduced in orthodontics by Dolphin Imaging System (USA). The system makes use of a headholder (like the one used in cephalostat ) to orient the skull/face. A camera grabs the digital image of the face . The DIGIGRAPH sonic digitisation is more accurate for soft tissue surface landmarks and values of linear measurements but relatively less precise than cephalometric for other skeletal and dental parameters. The DigiGraph Work Station, Part 2: Clinical Management JCO 1990

38. Non-radiation 3D face scanning 3D topography evaluation without hazards of the X-rays (Frey M et.al 2011) have been made to measure the 3D complexity of the human face, it includes stereophotogrammetry ,image subtraction technique, laser scanning , light luminance scanning and video systems . Laser scanning Widely used in anthropometric studies. The first laser scanning system for routine clinical use was introduced by Moss et al . in 1991 . Drawbacks Laser scanning systems are longer capture duration (8-10 s), Lack of ability to record soft tissue texture, and Need for safety of eyes during scanning, which may interfere with natural facial expression

39. Stereophotogrammetry Stereophotogrammetry is a method that utilises means of triangulation and using two cameras in stereo configuration for recording depth, to create 3D face image 3dMD face analysis system can capture facial contours in 180-200 degrees from ear to ear in the ultra-fast speed of fewer than 1.5 ms that means cameras can record the images unaffected by the movement, which is unavoidable in children The system accurately documents the patient's natural head position and multiple facial expressions noninvasively during various stages of treatment cycle 1. 3dMD 2. Axis three 3. Di3D 4. Genex 5. 3D-shape 6. Fuel 3D

40. '4D'imaging The assessment and quantification of facial muscle movements are critical for diagnosis, treatment planning and evaluation of surgical outcome in patients with facial deformities such as cleft lip and palate. For this purpose the motion capture stereophotogrammetry systems were introduced. Four-dimensional (4D) facial imaging can be defined as a time sequence of 3D models of facial animations. The 4D technology acquires accurate 3D surface information at approx. 60 frames/sec from various coordinated standpoints for up to a l0-min long resolution cycle. 3dMDfaceTM dynamic system (3dMD, Atlanta, GA) 4D capture system (DI3DTM), Dimensional Imaging,

41. Non-radiation imaging techniques Magnetic resonance imaging (MRI) NMR phenomena were discovered by Bloch and Purcell in 1946 MRI uses non-ionizing radiation to produce an MR image, the patient is placed inside a large magnet, which induces a relatively strong external magnetic field. This causes nuclei of many atoms in the body including hydrogen, to align themselves with the magnetic field. After application of RF signal,energy is released from the body,& detected and used to construct the MR image by the computer.

42. MRI applications in orthodontics In the diagnosis of TMJ disorders ( Dentisrty - First by Helms et al. in 1984 ). Disc position, condylar erosions ,adhesions, perforations & joint effusion & disc displacement (accurate as arthro -tomography ) In evaluating the TMJ adaptations following functional appliances (Orthodontics - the first MRI, a study of TMJ following Herbst appliance therapy -1998) In evaluating the jaw muscles and craniofacial morphology. It has also been used in measuring the cross-sectional area & muscle volume in response to myofunctional appliance. 3D reconstruction of jaw muscles is possible using software applications like 3D Doctor (Able Software Corp., Lexington, USA).

43. Ultrasonography - Nano -LIPUS devices Ultrasound is a form of mechanical energy that is transmitted through and into biological tissues as an acoustic pressure wave at frequencies above the limit of human hearing, is used widely in medicine as a therapeutic, operative, and diagnostic tool . ( 2.5-15 MHz ) 45

44. The device will be easily mounted on a bracket or a plastic removable crown . An energy sensor can also be used that will ensure the LIPUS power is reaching the target area of the teeth roots within the bone. LIPUS - Enhance bone growth into Ti porous–coated implants for osseointegration and bone healing after fracture and after mandibular distraction osteogenesis and has also used for stimulating mandibular cartilaginous growth. Based on the observation that LIPUS can promote dental tissue formation in rabbits, El Bialy et al. concluded that it may also be used to treat root resorption . 46

45. 3D digital dental scanners Contact scanners The contact scanners map the surface of an object through physical touch using probe like instruments. Coordinate measuring machine Non-contact scanners The non-contact scanners use radiation or light source and detect its reflection or distortion. 3D laser scanners , Photogrammetry , Interferometric techniques ,Structured light method, Confocal microscopy

46. 3D digital models E-models are three-dimensional (3D) digital models that help to eliminate the need for traditional plaster models in orthodontic practice Duret first introduced the concept of scanning dental arch in 1973. The first orthodontics scanning system was developed by OrthoCAD ( Cadent,USA ) in 1999 and followed by E-models ( Geodigm Corp.,USA ) in 2001 . The first 3D intraoral scanner was introduced by CEREC(Siemens, Germany). It was based on the technology using an infrared camera and use of optical powder (Tio2) on the teeth to creare a 3D model & recent scanners upgraded ( do not require powdering). 1.Intraoral scanners 2. Impression/model scanners 3. 3D CT-based Direct & Indirect method

47. Intraoral scanners 1. iTero*, Cadent Inc., Carlstadt, USA 2. CEREC AC Bluecam ,Germany 3. Lava -3M ESPE, St. paul, USA 4. Trios - by 3SHAPE A/S (Denmark) 5. Lythos , Ormco Corporation 6. CS 3500, Carestream 7. PlanScan marketed by Planmeca 3D desktop scanners 1.Ortho Insight 3D (Motion ViewSoftware ) 2. R series, 3 Shape (Denmark) 3. Maestro 3D (ACE Solutions,ltaly )

48. 3D volumetric analysis, and clinical implications of the upper airway and sinuses Non radiation methods Acoustic reflection MRI Radiation methods Fluoroscopy CT CBCT

49. Clinical implication of volumetric airway analysis Mandibular advancement in skeketal base II malocclusion Rapid maxillary expansion & maxillary protraction Orthognathic surgery Extraction therapy & effecys on airway The Hitachi MercuRay (Japan) has a stationary mode of a 10 sec recording, which can evaluate real time movement of oral & pharyngeal region, & proves to be useful in evaluating amount of the airway changes in mid sagittal view of an awake subject while sitting upright . 3D airway evaluation in 387 subjects from one university orthodontic clinic using CBCT Chiang CC et al .Angle Ortho 2012

50. The 3D triad in orthodontics When these 3D technologies are combined using 3D software programmes , 3D virtual orthodontic/surgical planning can be performed digitally . The integrated approach using these 3D data not only provides a smooth digital workflow in orthodontics but may also offer reduced errors related to materials, appliance fabrication and operator skills Craniofacial Skeleton Dentition Soft Facial Tissue Face Scanner Intraoral Scanner CBCT

51. Recent advances in Appliances

52. Customized Appliances Orthodontic appliances that are custom made to fit each individual patient’s teeth, and designed to move teeth from their initial malocclusion to a pre-determined outcome. Invisalign , first introduced by Align Technology, Inc (USA ) in 1997, is a technique that uses a series of customized transparent, removable aligners , which are designed and created using advanced computer technology, to orthodontically straighten teeth

53. Suresmile ® system SureSmile , a product of OraMetrix (Richardson, TX, USA), is an orthodontic digital system that uses an optical intraoral scanner to acquire a 3D digital model of teeth and brackets . Customized arch wires are robotically formed to incorporate all necessary bends to exert forces and moments to achieve the desired position of teeth. Custom wires are used in non custom brackets to achieve an individualized treatment outcome.

54. Incognito ™ system - fully customized lingual bracket system . Laboratory or digital set up is used to predetermine the desired positions of teeth. All lingual brackets are individually designed to closely adapt to lingual anatomy of all teeth. Custom arch wires are robotically formed to incorporate all necessary bends to exert forces and moments to achieve the desired position of teeth.

55. Ormco ®’s Insignia ™ - One of the most comprehensive CAD/CAM orthodontic appliances on the market, which was available in standard and self-ligating applications with optional use of esthetic ceramic brackets The organization offers patient-specific brackets, indirect-bonding transfer jigs, and custom archwires . The custom archwires are made by a printing robot that uses the system provided to trace and bend the wire accordingly, the robot is very accurate and has a very small error margin

56. Robotics arch wire bending Cartesian type archwire bending robot (LAMDA) Lingual archwire manufacturing and design aid Motoman up6

57. Bio MEMS/NEMS for Orthodontic Tooth Movement & Maxillary Expansion Concept - Animal experiments indicated that when 15–20 μA of low direct current (DC) was applied to the alveolar bone to modifying the bioelectric potential osteoblasts and PDL cells , there is increased concentrations of the second messengers, cAMP and cGMP, leads to accelerated bone remodeling. Nanorobotics- Futuristic Approach Nanorobotics are self-sufficient machines which are functional at the nanoscale. Nanorobots with specific motility mechanisms would navigate through periodontium to remodel it directly allowing accelerated orthodontic tooth movement.

58. 3-D Printing in Orthodontics A three-dimensional (3-D) printing is also known as additive manufacturing or desktop fabrication. It is a process of making 3-D solid objects from a digital file . MATERIALS USED TO PRINT 3-D OBJECTS The known three PolyJet dental materials Clear Bio-compatible (MED610 ) Vero Dent Plus (MED690 ) Vero Glaze (MED620) Website with 3-D models database: • 3-D Marvels •3-D Via • GrabCAD • Google 3-D Warehouse 3-D modeling software which can be downloaded for free : 1 . Google SketchUp 2. Tinkercad . 3 . Blender

59. PIEZOCISION Dibard and colleagues have developed a minimally invasive technique that combines piezoelectric incisions and microincisions with selective tunneling that helps to produce hard and soft tissue grafting The new approach has led to reduced orthodontic treatment time, minimal postoperation discomfort, great patient acceptance, and enhanced or stronger periodontium. Histochemical studies have shown that piezocision is less invasive and less traumatic than corticotomy procedures, and bone can regenerate in up to 8 weeks . However , one problem associated with it is that it can create gingival defect .

60. Ideal Mini-Implant Surface Using Nanoparticles Currently, TADs are manufactured with smooth titanium surfaces because Biocompatible coatings like Titanium nanotubes are studied to evaluate if the nanotubular layer can enhance initial osseointegration and can serve as an interfacial layer between the newly formed bone and the TAD. To Improve the Primary Stability of TADs Nanostenciled RGD( Arg - Gly -Asp) -gold patterns Tricalcium phosphate (TCP) nanocoating Ultrafine grain-sized titanium (UFG Ti) 63 Complete osseointegration is a disadvantage that complicates their removal. Lack of osseointegration is also one of the factors for the failure of TADs.

61. Recent advances in Bioengineering

62. Orthodontics in the year 2047 Genetically driven treatment plans Havens, B. Wadhwa , S. and Nanda, R.: J. Clin . Orthod . 41:549-556, 2007 Gene therapy for sutural growth disturbances: Mutations in FGFR2 have been linked to several human craniosynostosis disorders, including Apert , & Crouzon syndromes. In cases of craniosynostosis involving mutations in FGFR2, temporarily blocking FGFR2 signaling in the preosteoblasts within the sutural mesenchyme or providing a different anti proliferation signal to these cells would allow normal sutural growth without surgical intervention.

63. Gene therapy to enhance condylar growth using rAAV -VEGF Objective : To test the hypothesis that the introduction of specific vascular growth inducing genes would favorably affect mandibular condyle growth in rats over a limited experimental period Result : Enhancement of mandibular condyle growth occurred in backward and upward direction in VEGF group rather than control group . Local RANKL gene transfer to the periodontal tissue accelerates orthodontic tooth movement Kanzaki.H et al Gene Therapy 2006 Result – It was demonstrated that transfer of the RANKL gene to the periodontal-tissue ,activate osteoclastogenesis and accelerated the amount of experimental Toot movement. Local RANKL gene transfer might be a useful tool not only for shortening orthodontic treatment, but also for moving ankylosed teeth where teeth, fuse to the surrounding bone .

64. Conclusion There have been many technological advances in orthodontics that have improved diagnosis, treatment planning, treatment precision, and treatment efficiency. However , none of these advances are a substitute for sound diagnosis, and clinical judgment. A high-tech customized orthodontic appliance that is capable of achieving excellent results with high precision will still result in a bad outcome if the diagnosis and treatment plan are not well thought out.

65. References Orthodontics, current principles and techniques by Graber & Vanarsdall -6th edition Contemporary orthodontics by William Proffit - 5th edition Up in the Air:Orthodontic technology unplugged! 2017 APOS Trends in Orthodontics Smart bracket for multidimensional force and moment measurement.J Dent Res 86(1): 73–78 The DigiGraph Work Station, Part 2: Clinical Management JCO 1990 Shetty NJ, Swati P, David K. Nanorobots : Future in dentistry.Saudi Dent J. 2013; 25(2 ) Orthodontics – Diagnosis and mangement of malocclusion and dentofacial abnormalities – Om Prakash Kharbanda – 3 rd edition