Impact of selective alveolar decortication on bisphosphonate burdened alveolar bone during orthodontic tooth movement.
OBJECTIVE
To investigate the effect of Selective Alveolar Decortication (SADc) facilitated orthodontic tooth movement (OTM) on bisphosphonate burdened alveolar bone in a rodent model.


METHODS
OTM was accomplished by protraction of the maxillary right first molars. Four groups were included of which two groups were pre-treated for three months with alendronate sodium (BP+TM+SADc and BP+TM group) and two groups were given saline (TM+SADc and TM group). Selective alveolar decortication surgery was performed on day 1 of appliance insertion. OTM measurements were obtained at 0, 4, and 8 weeks using in-vivo μCT. Tissues were analysed by histology and EPMA.


RESULTS
Tooth movement of 0.39 mm and 0.75 mm in the BP+TM+SADc group at 4 and 8 weeks respectively was achieved with 113% increase in tooth movement compared to BP+TM group at 4 weeks. In comparison, SADc+TM group showed 0.63 mm and 2.1 mm of tooth movement at 4 weeks and 8 weeks respectively with only 6% increase at 4 weeks and 2% increase at 8 weeks compared to TM group. Severe interproximal and buccal bone loss around the first permanent molar in the BP+TM+SADc group was seen with μCT imaging and histology. Animals in BP+TM+SADc group histologically showed signs of osteonecrotic bone with irregular borders, loss of osteocytes and absence of osteocytic lacunae.


CONCLUSIONS
This study demonstrated selective alveolar decortication accelerates tooth movement in a bisphosphonate burdened alveolar bone in the short term but the potential of such an invasive injury can have adverse effects.
Division of Orthodontics, 5-478 Edmonton Clinic Health Academy, Edmonton, AB T6G 2E1, Canada; Department of Dentistry, 5-478 Edmonton Clinic Health Academy, Edmonton, AB1, T6G 2E1, Canada. Electronic address: kaipatur@ualberta.ca.
Neelambar
N
Kaipatur
Division of Orthodontics, 5-478 Edmonton Clinic Health Academy, Edmonton, AB T6G 2E1, Canada; Department of Dentistry, 5-478 Edmonton Clinic Health Academy, Edmonton, AB1, T6G 2E1, Canada. Electronic address: major@ualberta.ca.
Paul
P
Major
Department of Dentistry, 5-478 Edmonton Clinic Health Academy, Edmonton, AB1, T6G 2E1, Canada. Electronic address: tom.stevenson@ualberta.ca.
Thomas
T
Stevenson
Department of Dentistry, 5-478 Edmonton Clinic Health Academy, Edmonton, AB1, T6G 2E1, Canada. Electronic address: dj.pehowich@ualberta.ca.
Dan
D
Pehowich
Department of Civil and Environmental Engineering, 3-021 Markin/CNRL NREF, Edmonton, AB T6G 2E1, Canada. Electronic address: samer.adeeb@ualberta.ca.
Samer
S
Adeeb
Faculty of Pharmacy & Pharmaceutical Sciences, 2020-J Katz Group Centre, University of Alberta, Edmonton, AB T6G 2E1, Canada. Electronic address: mdoschak@ualberta.ca.
Michael
M
Doschak
D019386:Alendronate / Q000009:adverse effects / Q000494:pharmacology*; D000539:Alveolar Process / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D016723:Bone Remodeling / Q000187:drug effects* / Q000502:physiology; D004577:Electron Probe Microanalysis; D005260:Female; D008437:Maxilla / Q000187:drug effects / Q000502:physiology; D023421:Models, Animal; D008963:Molar / Q000000981:diagnostic imaging / Q000502:physiology; D052280:Orthodontic Anchorage Procedures; D010020:Osteonecrosis; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014087:Tooth Movement Techniques / Q000379:methods*; D055114:X-Ray Microtomography / Q000379:methods
D019386:Alendronate
Bisphosphonate; Bone burden; Electron probe microanalysis; Micro-computed tomography imaging; Orthodontic tooth movement; Selective alveolar decortication