Prevalence of extraction space reopening in different orthodontic treatment protocols

Longitudinal evaluation of extraction space closure, at final, medium and long-term, and its association with the adopted protocol, in patients treated in the last 40 years, with several initial malocclusions

“…11,14,74 Although there is no work reporting the space behavior in Class III treatment in the literature, similar results of it was obtained by the present study were found already previously in Class I and Class II studies. 29,39 The low closing rate found in this study is still better than which was reported by previous study, that found closed spaces at the final of the treatment only in 31.4% of patients. 14 However it can be due the different orthodontic systems applied, bonded brackets and banded teeth, respectively.…”

“…The random errors ranged from 0.01 to 0.02 and were considered acceptable and within normal ranges. 39 No significant systematic errors were found (Table I).…”

“…Nonetheless, studies reporting open spaces at the end of treatment and relating the difficult to obtain only cases with closed spaces to the samples are common and frequent in the literature. 13,16,30,39,70 There are basically three intraoral methods to close extraction spaces: coil springs, reciprocal dental movement with elastics and unilateral movement with absolute anchorage. [71][72][73] All these methods were only subject on the attention and dedication of the orthodontist.…”

“…School, University of São Paulo, with dental extractions, during 40 years, independent of the initial malocclusion or extraction treatment protocol, 38 were selected using inclusion and exclusion criteria. 16,39 The maxillary retention protocol of all patients consisted of a removable Hawley plate used continuously, except during meals, for 6 months and only during sleeping for an additional six months. The mandibular retainer consisted of a bonded canine-to-canine lingual wire used during a mean period of 3 years.…”

“…The extraction spaces were measured in all quadrants, starting from 0.1mm. 39,[41][42][43][44] The spaces were measured from distal face of the extraction space mesial adjacent tooth to the mesial face of the extraction space distal tooth of the same quadrant. 39 Error study…”