45
Participants
Start Date
July 1, 2016
Primary Completion Date
September 16, 2021
Study Completion Date
September 16, 2021
Piezocision
The first maxillary premolars will be extracted with orthodontic purpose. After 3 months of extraction, the orthodontic alignment and dental leveling will be obtained and a 0.016x0.022 stainless steel wire will be placed, as well as orthodontic mini-implants (Morelli®, Sorocaba, SP, Brazil). The retraction of the canines will begin using closed nickel-titanium spring (120g). The piezocision surgery will be performed only in one side of the mouth. Three vertical piezo-incisions will be performed near the edentulous region and mesially to the canine root, in the vestibular alveolar cortical bone with the Ultrasonic instrument (BS1 insert Piezotome ™, Satelec Group Acteon Merignac, France) in depth of 3 mm. The intraoral digital scans will be performed with 7 and 14 days after the start of retraction, and then 14 in 14 days to a maximum period of 6 months. The patients will be advised to take analgesics (paracetamol or dipyrone) only if necessary.
Corticotomy
The first maxillary premolars will be extracted with orthodontic purpose. After 3 months of extraction, the orthodontic alignment and dental leveling will be obtained and a 0.016x0.022 stainless steel wire will be placed, as well as orthodontic mini-implants (Morelli, Sorocaba, SP, Brazil).The retraction of the canines will begin using closed nickel-titanium spring (120g).The corticotomy surgery will be performed at the day of begining of canine retraction only in one side of the mouth.A mucoperiosteal flap will be raised from the extraction region to the mesial of the canine.Perforations will be performed using a number 2 spherical drill bit in low speed handpiece under irrigation, only in the cortical none depth.The intraoral digital scans will be performed with 7 and 14 days after the start of retraction, and then 14 in 14 days to a maximum period of 6 months.The patients will be advised to take analgesics (paracetamol or dipyrone) only if necessary.
Control Side
The first maxillary premolars will be extracted with orthodontic purpose. Fixed orthodontic appliance will be bonded (0.022x0.025 slot with MBT prescription in incisors and Standart in the other teeth) with a power arm welded in the bracks upper canines brackets. After 3 months of extraction, the alignment and dental leveling will be obtained and a 0.016x0.022 stainless steel wire will be placed, as well as orthodontic mini-implants (Morelli®, Sorocaba, SP, Brazil) between the roots of the second premolars and molars. At that time an intra-oral digital scan will be performed. The retraction of the canines will begin using closed nickel-titanium spring (120g of force) from the power arm to the mini-implant. No surgery will be done at this side. The intraoral digital scans will be performed with 7 and 14 days after the start of retraction, and then 14 in 14 days to a maximum period of 6 months.
Micro-osteoperforations
All micro-osteoperforations will be performed only once time in the experimental group on the same day of the installation of the upper incisors' retraction mechanics. Perforations will be performed with an individualized surgical guide and a 1.6 mm diameter stainless steel surgical drill perpendicular to the alveolar bone, 3 mm deep on the buccal surface, and 5 mm, on the palate. The depth of the perforations will be controlled and standardized by a cursor developed and patented by the research group. Two micro-osteoperforations will be aligned vertically distally from each upper incisor. Due to the proximity of the roots in the cervical third, only the most apical perforation will be performed between the two central incisors. The first perforation will be performed 6 mm away from the gingival margin, and the second, 5 mm from the first, in the vertical direction.
Pontifícia Universidade Católica de Minas Gerais, Belo Horizonte
Fundação de Amparo à Pesquisa do estado de Minas Gerais
OTHER
Pontifícia Universidade Católica de Minas Gerais
OTHER