Ormco made the TARG in 1984 and this
was subsequently modified over the years with minor
improvements to facilitate indirect bonding which was
considered imperative for the lingual technique.
Other techniques were used such as the CLASS and Hiro for better positioning of brackets, but what about the labial technique…why did they not improve the indirect technique for increased precision?  

 
 

                CAD / CAM systems were, and are being produced but are still expensive. “Incognito” (love the name!) from Dr Dirk Weichmann, which has recently been bought by 3M uses cast gold brackets, so prices are expected to be as high as ever. Gold as an alloy can also have bonding problems. Other systems such as Orapix, which is based on Dr Fillion’s B.E.S.T system offer alternatives in lingual bonding, but what about labial?  Orthocad offers virtual set-ups but this information has to be practically transferred to the working model and brackets have to be positioned. Same goes for the OraMetrix system which relies on robot wire bending and a series of wires that will move the teeth into position. However the wires need to work on the brackets and unless the brackets are positioned precisely, how can the precise wires do their job?The addition of NASSA technology in the form of heat activated SMA archwires was also one of the advances in fixed orthodontics. 

               Looking through the internet we can find many systems offered for Labial Indirect Bonding, but most of them seem to be based on the same theories, with exception to the tray fabrication and this has been the cause of many papers being written comparing Indirect with Direct bonding. Arguments have developed as to which is the more accurate and which is best for bonding results.

               Ortho Quest, Specialty Appliances, just to name a couple of big ones, advertises their systems in depth, explaining graphically the methods used and their advantages. Many labs all over the world are copying these techniques. They certainly have the most professional approach and very clear instructions, but again, under the glossary, the techniques for bonding are the same.

                I am amazed at some of the websites I have found with comments like “X marks the spot”, “taking care to centre the bracket as much as possible” and even “Once the brackets have been ‘diddled’ into position”. This was from an article in 2007.

I1979 it was reported that only 17% or Orthodontists used indirect bonding techniques

  
                In the book “Systemized Orthodontic Treatment Mechanics” (2001), Mclaughlin, Bennet and Trevisi wrote…”Indirect bonding is more accurate, especially in the molar regions, and has the advantage that no separation appointment is needed. This technique reduces the amount of chairside time….Although there are disadvantages, it is likely that indirect bonding will see greater use than in the past. This is due to the need for greater accuracy in bracket positioning and because of the improved techniques and materials which are currently available.”  
  We refer to these techniques as “Eye and Hand” and various products are used in their manufacture. Usually ‘sugar daddy’, wax or composite is used to place the brackets on the models, either by tweezers‘to a predetermined place “X” ‘, or by use of a hand jig which will position the brackets at a particular height setting. Unfortunately the jig will not control Torque or Angulation which is meant to be controlled by the pre-programmed slot angles made in the factory.  
                The only problem with this approach is how do you really know that you have placed the bracket at the desired torque and angulation? Movements of hand, discrepancies by eye, are all probabilities to a non-standardized approach which relies on the judgment of the technicians or assistants. The slightest movement of the hand could change both torque and angulation by several degrees!  
                The Sondhi approach was a good idea to eliminate the excess material being used to bond in the mouth and improve bond strength, but again it did not increase precision of the bracket placement to the model.Light cured composites are generally stronger and are easy to use. “Transbond XT” from 3M is a very good choice with a comprehensive system of primers, etc and good handling properties.  
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