Tipping

One of the major uses of removable appliances is to move one incisor over the bite as shown in Figs 2a-d. A simple upper removable appliance utilized a 'T' spring constructed from 0.5 mm wire activated 1-2 mm which delivered a force of about 30 g to the tooth. After only a few weeks the cross bite was corrected without the need for complex treatment. Note the anterior

Fig. 1a-c A 9 year-old patient with an anterior open bite caused by a thumb sucking habit. Note the wear on the thumb as a result of this. She was fitted with a simple upper removable appliance and gently encouraged to stop the habit. She did so successfully and the open bite closed down spontaneously in 6 months

Fig. 1a-c A 9 year-old patient with an anterior open bite caused by a thumb sucking habit. Note the wear on the thumb as a result of this. She was fitted with a simple upper removable appliance and gently encouraged to stop the habit. She did so successfully and the open bite closed down spontaneously in 6 months

Fig. 2a an anterior cross bite involving the upper left and lower left central incisors
Adam Central Incisor

Fig. 2b An upper removable appliance with Adams cribs for retention made from 0.7 mm wire on the first permanent molars and the upper left central incisor. A 'T' spring made from 0.5 mm wire is used to push the tooth over the bite. The anterior retention is to prevent the front of the appliance being displaced as the spring is activated

Orthodontic Adams Clasp Centrals

Fig. 2c The appliance in place. The T spring is activated 1-2 mm every 4 weeks

Fig. 2d The completed case. Active treatment took 12 weeks retaining clasp that prevents the appliance from displacing downwards when the spring is activated.

If teeth are to be pushed over the bite with removable appliances, a stable result is more likely to be achieved if the tooth is retroclined in the first instance, the overbite is deep and there is an anterior mandibular displacement associated with a premature contact. Tipping teeth tends to reduce the overbite because the tip of the tooth moves along the arc of a circle as shown in Figure 3 a. Excessive tipping may also make the tooth too horizontal which can be not only aesthetically unacceptable but may also

Fig. 3a The effect of tipping anterior teeth on the overbite. As the teeth move around a centre of rotation the incisal tip moves along the arc of a circle. By the laws of geometry, as the tooth is proclined the overbite reduces once it moves past the vertical

Fig. 3b Excessive tipping not only reduces the overbite but also makes the axial inclination of the teeth too horizontal. In these situations stability is reduced, the appearance is poor and the tooth may suffer from unwanted non-axial loading

Fig. 4a Both the upper lateral incisors are in cross Fig. 4b An upper removable appliance was used to bite tip the laterals over the bite

Fig. 4c The cross bites have been corrected. Note the reduction in the overbite

Fig. 4c The cross bites have been corrected. Note the reduction in the overbite

Fig. 4d 6 months later the upper right lateral has relapsed into cross bite due to the reduced overbite result in excessive non-axial loading of the tooth as illustrated in Figure 3b.

Overbite reduction when teeth are over proclined is illustrated in Figures 4a-d. In this case both the upper lateral incisors were pushed over the bite with an upper removable appliance. The cross bite was corrected but note the reduction in overbite on the lateral incisors. Six months after completion of treatment the upper right lateral had relapsed back into cross bite.

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  • joona
    What is tipping in ortho treatment?
    8 years ago

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