Speed of Premolar Extraction Space Closure: Healed vs Recent Extraction Site
Speed of Premolar Extraction Space Closure: Healed vs Recent Extraction Site
The aim was to compare the rate of teeth movement into fresh and old extraction sites.
Trial design: Randomized controlled clinical trial with a split mouth design. Setting: Jordan
 University of Science and Technology(JUST) Postgraduate Dental Teaching Clinics and labs.

 Participants and interventions: Twenty-eight subjects with bimaxillary proclination requiring
 extraction of all first premolar teeth participated in this study. In the lower arch, two
 groups were also identified; group 1 having the first premolar extracted before the
 commencement of orthodontic treatment and group 2 having the first premolar extracted just
 before space closure when 0.019 x 0.025 inch SS archwire was reached. Patients were
 followed-up monthly for three months. At every follow-up visit lower alginate impressions
 were taken. Extraction spaces in the lower arch follow-up models were measured using digital
 caliper.

 The rate of extraction space closure in the lower arch was assessed monthly.
Inclusion Criteria:

 -  Age ≥ 16 years

 -  Proclined upper and lower incisors (Ui/max >115 o, Li/mand >99o)

 -  Mild upper and lower arch crowding (<4mm) or no crowding

 -  Need for upper and lower first premolars extraction

 -  Skeletal I malocclusion (1<ANB <5)

 -  Average lower facial height and maxillomandibular plane angle (22 o <MM<32 o)

 -  Class I canine relationship

 -  Good oral hygiene and healthy periodontium

 Exclusion Criteria:

 -  Poor oral hygiene

 -  Diseases and medications that were likely to affect bone biology

 -  Previous orthodontic treatment

 -  Evidence of bone loss

 -  Active periodontal disease

 -  Smoking