Comparative evaluation of the amount, rate and type of tooth movement during canine retraction between healed versus recent upper premolar extraction site: a split mouth randomised controlled trial.

Orthodontic treatment duration depends on several factors like severity of malocclusion, treatment plan (extraction or non-extraction), patient compliance during treatment etc. Specially Extraction case therapy requires 18–24 months. In this treatment, extraction space closure consumes one-third to one-half of orthodontic treatment duration. In adult patients, lengthy orthodontic treatment is often accompanied with periodontal problems such as root resorption, alveolar bone loss, and gingival recession. Lengthy treatment is also responsible for poor patient compliance. Therefore, acceleration of orthodontic treatment becomes a good choice for Orthodontists for harnessing patients and doctor’s interest. Patients are keen for fast treatment due to treatment discomfort, social, and aesthetic concerns. To explore such treatment strategies many studies were conducted. Studies of tooth movement into a recent extraction site found accelerated tooth movement as compared to the site with healed socket. Thus, it was proposed that retraction of a tooth toward a recent extraction site is more advantageous compared to delayed retraction after extraction. Greater adjacent tooth tipping was reported when teeth were moved toward recent extraction sites as compared to healed extraction sites. The increased tipping on the recent extraction side was justified by the increased movement and the apical repositioning of the centre of resistance after adjacent tooth extraction. In contrast to these findings, another study, reported greater tooth retraction velocity into a healed socket than into a recent extraction socket. Also, similar tipping of teeth in both healed and recently extracted premolar sites have been found in some studies. A frequent complication associated with orthodontic space closure, after permanent tooth extraction, is development of a gingival cleft (GC), often also called invagination and infolding of gingiva. Gingival clefts have been reported to develop in about 35% to 100% of the extraction cases and are more frequent in the mandible. Some studies have suggested that gingival cleft development is a frequent finding during orthodontic space closure and seems to occur more frequently with early tooth movement initiation. On the contrary, other studies have found that the incidence of the gingival clefts did not vary in a statistically demonstrable fashion with the amount of time elapsing between tooth extraction and the initiation of orthodontic space closure. Thus, there is no conclusive data about how tooth movement varies in a recent extraction site as compared to a healed extraction site. Therefore, my study aims to evaluate the amount, rate and type of tooth movement during canine retraction in a recent versus healed extraction site of upper first premolar. This study will also be assessing gingival cleft formation in recent versus healed extraction site.