Textbook for Orthodontic Therapists. Ceri Davies

1 History of Orthodontics

      The practice of orthodontics, as we know it today, is not just about correcting the position of misaligned teeth, but has a long history behind it. Teeth are important to us, and even in ancient times they were of interest. Archaeologists have found attempts to straighten teeth on human skulls, which had wire wrapped around the teeth in an attempt to realign them. It has taken the knowledge and written works of many dentists and orthodontists to reach the current state of the science.

1.1 Orthodontics before the Twenty‐First Century

      Modern orthodontics began developing around the eighteenth and nineteenth centuries, but was not known as a specialism until 1900. The appliances that were developed and used over that time were very different to the appliances we use today. A French dentist named Pierre Fauchard designed the first expansion appliance in 1723, which was known as the Bandeau. This consisted of a U‐shaped metal strip to which the teeth were ligated. The ligation helped to create expansion. In the late eighteenth century, an American dentist, Norman W. Kingsley, started using an early form of headgear, a traction device to help move teeth distally. The very first type of headgear was created in 1840 and was known as the chin cup. Removable appliances were not used much at this time due to the retention making stability poor. It was not until 1949, when Adams clasps were introduced, that their use became more widespread. A Dwinelle's jack screw was a popular screw to use within removable appliances in the nineteenth century, quite similar to the screws we use on patients today.

      Functional appliances only started to be developed in 1879 and again this was by Norman W. Kingsley. The functionals we know today work by posturing the mandible forward, whereas Kingsley designed one that would make the bite jump into the desired position. After this, many more functional appliances were produced, some removable and others fixed. Examples of removable functionals are the monobloc by Pierre Robin in 1902, the medium opening activator by Viggo Andresen in 1990 and the Frankel functional appliances FR‐1, FR‐2 and FR3, all designed by Rolf Frankel in 1957. An example of a fixed functional is the Herbst, produced in 1905 by Emil Herbst. Clark's twin block is a very popular functional appliance, still used today due to being well tolerated by most patients. This was developed by William Clark and has been used since the 1980s. Fixed appliances were employed very regularly by 1970, although they were slightly different from those we use today.

Edward Angle produced a number of appliances, including in 1904 Angle's E (expansion) arch, which consisted of molar bands with a labial archwire connecting from one molar band to the other running across the labial aspect of the dentition. Teeth needing expansion were then ligated to the archwire. Around 1910 Angle realised that he needed more control of the teeth, so to gain this he developed the pin and tube appliance. Gold and platinum bands were used on all the teeth with a vertical tube soldered onto them, then a pin was used which passed through this tube, achieving tooth movement. The downside of this was that rotational movement and root parallelism were difficult to achieve due to the use of round archwires. The pins had to be removed and resoldered into a new position at every appointment. The ribbon arch was the next appliance that Angle developed in 1915. With this rotational movement was achievable due to the vertical bracket soldered onto each band. Raymond Begg was inspired by this appliance and went on to develop his lightwire technique from it. Five years before Angle died in 1930, his final invention was the edgewise appliance, which was a bracket with a horizontal slot that was identical for every tooth. Angle moved away from the vertical slot, since he found that using a horizontal slot meant rectangular archwires could be used and by placing bends this allowed three‐dimensional control of the teeth. The preadjusted edgewise appliance used today is based on Angle’s edgewise appliance.

      During the twentieth century fixed appliances consisted of bands with brackets welded onto them. Bands were made chairside by using straight strips of stainless steel that were shaped for each individual tooth, but as you might imagine this was very time consuming. In 1930 these stainless steel bands began being sold ready made by the very first orthodontic supply company. The purpose of the bracket was to hold the archwire in place. Tooth movement was achieved by the orthodontist placing bends within the archwire. Again, this was very time consuming and it took hours to get fixed appliances onto a patient.

      In 1970, Lawrence Andrews developed the preadjusted edgewise appliance which is still popular today, and this changed much in orthodontics. The difference with this appliance was that the brackets were made for each specific tooth and contained prescriptions such as in and out, tip and torque within the bracket. These prescriptions all helped with tooth movement and reduced the need for wire bending. Today these prescription brackets are available with different angulations, slot sizes and base types.

      Aesthetic brackets first become available in 1963, which are very popular today, as are lingual appliances, the first of which were developed in the 1980s. Since then a wide range of different systems have been developed by orthodontists, including the standard edgewise appliance, Begg appliance, tip edge appliance, preadjusted edgewise appliance, self‐ligating appliance, and the lingual appliance system. We will look at each of these in turn.

1.2 Standard Edgewise Appliance

      Edward Angle (1855–1930):

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