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Edward Angle (1855–1930):

 Developed the standard edgewise appliance in 1925.

 Was an American dentist and was known as the ‘Father of orthodontics’.

 Attended Pennsylvania College of Dental Surgery and qualified in 1878 as a dentist.

 Founded the Angle School of Orthodontia in 1890, where orthodontics become known as a specialism.

 Angle’s classification of malocclusion that we use today was developed by him in 1890.

 Established many appliances within his lifetime, such as the E arch appliance (1907), the pin and tube appliance (1910), the ribbon arch appliance (1915) and the edgewise appliance (1925).

 In 1930 he died at the age of 75.

Figure 1.1 Standard edgewise bracket. The same bracket is used for every tooth which contains a passive bracket slot with no inbuilt prescription.

Figure 1.2 First‐, second‐, and third‐order bends.

Standard edgewise appliance (Figure 1.1):

 The design of the bracket was the same for every tooth which had a passive bracket slot.

 All brackets were rectangular in shape.

 The size of the bracket was determined by the width of the bracket slot.

 The brackets came in two different sizes:Width usually 0.018 or 0.022 in.Depth usually 0.025 or 0.028 in.

 The appliance had three‐dimensional control of the teeth.

 To aid tooth movement all archwires were dependent on bends being added. However, this was time consuming and difficult for the orthodontist, as it was required at every visit.

 The bends created were to achieve the following (Figure 1.2):First‐order bend – in and out:To compensate for the different tooth widths, bends are placed in the horizontal plane of the archwire.The bends correct the tooth widths in the bucco‐lingual and labial‐palatal direction (anterio‐posterior [AP] plane – anterior/posterior movement, front to back).For example: in modern‐day orthodontics, central incisors are always slightly in front of the lateral incisors, which sit slightly back. Canines sit in the same anterio‐posterior position as the central incisors, which helps to create the canine eminence (corner of the mouth).Second‐order bend – tip:To compensate and correct the angulation of the teeth, bends are placed in the vertical plane to achieve the correct mesiodistal angulation of the teeth.For example: distally angulated laterals would need bends to help upright the laterals mesially, which ensures that teeth gain the desired angulation.Third‐order bend – torque (rectangular wire only):This is achieved with rectangular archwires only.Orthodontists would place a bend in the archwire to help correct the torque of the roots.For example: buccal root torque is achieved by the archwire being twisted forwards; palatal root torque is achieved by the archwire being twisted backwards.

 Closing loops were placed within the archwire and used as a method of space closure.

 This system placed a high demand on anchorage.

 Tooth movement can be effected due to the inter‐bracket span, the distance between the brackets:Narrow brackets (more span): a greater span of the archwire between the brackets has the ability to make the archwire more flexible, which can achieve faster alignment.Wider brackets (less span): a reduced span of the archwire between the brackets is more efficient for de‐rotation and mesiodistal control of teeth.