Kanin distalizasyonunda bölümlü ve devamlı arkların etkilerinin karşılaştırmalı olarak incelenmesi

Abstract

SUMMARY Controlled retraction of canines is an essential biomechanical requirement for planned tooth movements. Canines can be retracted by sliding on a continuous arch wire or by the use of segmental arch wires in the Edgewise technique. The purpose of the present study is to compare the effects of the canine distalization by the PG canine retraction spring to those of the Ni-Ti closed coil spring used on a continuous arch wire in the same patient. Our study was conducted on both in the maxilla and mandibula of the 20 subjects with a mean age of 13 years 5 months. After the first premolar extraction and levelling of the teeth with 0.018 inch slot standard edgewise appliances, the right maxillary and mandibular canines were distalized by 0.016 - 0.022 inch PG canine retraction spring and the left maxillary and mandibular canines were distalized by a Ni-Ti closed coil spring on a 0.016 - 0.022 inch continuous arch wire. As the force generated by PG retraction arch was between 100-150 gr., activation of the Ni-Ti closed coil springs was performed to obtain the same amount of force in order to achieve the standardisation. The first molars were stabilised with a transpalatal arch of the Goshgarian type in the maxilla and with a lingual arch in the mandible. Linear and angular measurements were made on 40 lateral sefalograms and 40 model photocopies taken prior and at the end of canine retraction. The results were statistically evaluated.100 The overall comparison between the PG canine retraction spring and sliding mechanics showed that the retraction with the spring is more rapid both in the maxilla and mandible. A significant difference was found in the amount of canine retraction per month of treatment in the mandible between the two methods. Mesial movement of the upper first molars was significantly more than the lower first molars with the PG retraction arch. Ni-Ti closed coil springs are quite easy to place and much more comfortable and hygienic for the patient. If we can optimise the biomechanical systems related to canine retraction with the sectional arches, we may accomplish all controlled tooth movements obtained by sliding mechanics.

SUMMARY Controlled retraction of canines is an essential biomechanical requirement for planned tooth movements. Canines can be retracted by sliding on a continuous arch wire or by the use of segmental arch wires in the Edgewise technique. The purpose of the present study is to compare the effects of the canine distalization by the PG canine retraction spring to those of the Ni-Ti closed coil spring used on a continuous arch wire in the same patient. Our study was conducted on both in the maxilla and mandibula of the 20 subjects with a mean age of 13 years 5 months. After the first premolar extraction and levelling of the teeth with 0.018 inch slot standard edgewise appliances, the right maxillary and mandibular canines were distalized by 0.016 - 0.022 inch PG canine retraction spring and the left maxillary and mandibular canines were distalized by a Ni-Ti closed coil spring on a 0.016 - 0.022 inch continuous arch wire. As the force generated by PG retraction arch was between 100-150 gr., activation of the Ni-Ti closed coil springs was performed to obtain the same amount of force in order to achieve the standardisation. The first molars were stabilised with a transpalatal arch of the Goshgarian type in the maxilla and with a lingual arch in the mandible. Linear and angular measurements were made on 40 lateral sefalograms and 40 model photocopies taken prior and at the end of canine retraction. The results were statistically evaluated.100 The overall comparison between the PG canine retraction spring and sliding mechanics showed that the retraction with the spring is more rapid both in the maxilla and mandible. A significant difference was found in the amount of canine retraction per month of treatment in the mandible between the two methods. Mesial movement of the upper first molars was significantly more than the lower first molars with the PG retraction arch. Ni-Ti closed coil springs are quite easy to place and much more comfortable and hygienic for the patient. If we can optimise the biomechanical systems related to canine retraction with the sectional arches, we may accomplish all controlled tooth movements obtained by sliding mechanics.