الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 154 |  |  |
| | | from | 154 | | |
Abstract
Orthodontic treatment’s ultimate goal is to achieve maximum esthetics and function, with maximum benefits and minimum side effects. However, one of the major concerns both to patients and clinicians, is the long treatment duration, which usually ranges from 2-3 years. This long treatment time poses high risks of root resorption, dental caries, and patient burn out or loss of their compliance. Consequently, acceleration of tooth movement and shortening the treatment duration has been a major field of research in orthodontics, and several surgical non-surgical methods have been proposed. Corticotomy has been considered in past few decades as one of the most successful methods for acceleration. However, it could be considered relatively invasive by some patients as well as clinicians, since it requires flap reflection surgery. Thus, several less invasive methods have been suggested, recently including micro-osteoperforations (MOPs).
The aim of the present study was to evaluate the effect of MOPs on the rate of orthodontic tooth movement, assessed by the retraction of the maxillary canine. Additionally, canine tipping during retraction has been evaluated. The study design was a split-mouth randomized controlled clinical trial.
Ten patients were recruited for the study, requiring maxillary 1st premolar extraction, with subsequent canine retraction into the extraction space. The patients were also checked that they fit into the set inclusion criteria. After placement of maxillary and mandibular fixed orthodontic appliances, patients were referred for extraction of maxillary 1st premolars, followed by leveling and alignment of the arches. Before the start of canine retraction, mini-screws were placed in the buccal mucosa between the maxillary 2nd premolars and 1st molars
85
for anchorage reinforcement. Computer-aided randomization was utilized to randomly assign the experimental and control sides in each patient.
Micro-osteoperforations were performed distal to the canine on the experimental side, using PROPEL device. PROPEL is a disposable device with an adjustable penetration depth, and a light signal that turns on upon achieving the desired depth. Each perforation was 1.5 mm wide, and 2-3 mm deep. Canine retraction was performed using NiTi coil-springs with a force of 150 grams. Every 3 weeks, dental photographs and alginate impressions were taken and poured into dental casts till canine retraction is completed. Also, force level was checked and reactivated to maintain the 150 grams.
Data regarding the assessment of canine distal displacement, as well as canine tipping, were evaluated from dental casts. Canine distal movement was measured from the canine cusp tip relative to the medial end of the third palatal rugae. As for canine tipping during retraction, it was measured at three points on the canine clinical crown: incisal, middle, and cervical. Distances were measured between them and the same points identified on the adjacent lateral incisor crown.
Assessment of the rate of canine distal displacement revealed significant acceleration of tooth movement on the experimental side compared to that on the control side during the first 9 weeks of the study. Afterwards, the rate gradually decreased, resembling the rate of tooth movement on the control side. Additionally, the maxillary canine movement during retraction was not bodily, where clinically significant tipping has been reported on both the experimental and control sides. However, significantly greater tipping occurred on the experimental side.