Tissue responses resulting from tooth movement surgically assisted by corticotomy and corticision in rats.
OBJECTIVE
To compare the histological responses in corticotomy- and corticision-assisted tooth movement.


METHODS
Ninety Wistar rats were divided into three groups: C (control-tooth movement only), CT (tooth movement + corticotomy), and CI (tooth movement + corticision). Surgeries were performed on the vestibular and lingual cortical bone of the maxillary first molar. Tooth movement was carried out with nickel-titanium closed coil springs having a force of 30 g. The rats were sacrificed at 3, 14, and 28 days. To evaluate the number of osteoclasts and amount of root resorption, a tartrate-resistant acid phosphatase stain was used. Hematoxylin and eosin staining was performed for areas of hyalinization, and the organic bone matrix was stained with picrosirius.


RESULTS
The CT group showed a greater number of osteoclasts than did the C group on day 3 (P < .05). At the same time point, the CT and CI groups showed a delayed onset of organic bone matrix remodeling and a lower incidence of root resorption than did the C group (P < .05). There were also fewer hyalinization areas in the CI group than in the C group on day 3 (P < .05).


CONCLUSIONS
Corticotomy effectively increased bone resorption during the early stages of tooth movement, but this increase was not observed for corticision. The surgical procedures did not accelerate organic bone matrix remodeling. Corticotomies and corticisions decreased the risk of root resorption only during the early stages of movement. Corticision reduced the level of hyalinization, while corticotomy did not.
Ana Paula Lazzari Marques
AP
Peron
Aline Cristina Batista Rodrigues
AC
Johann
Vula
V
Papalexiou
Orlando Motohiro
OM
Tanaka
Odilon
O
Guariza-Filho
Sergio Aparecido
SA
Ignácio
Elisa Souza
ES
Camargo
D000539:Alveolar Process / Q000473:pathology / Q000601:surgery; D000818:Animals; D001696:Biomechanical Phenomena; D016723:Bone Remodeling / Q000502:physiology; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000473:pathology; D000071538:Cortical Bone / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008437:Maxilla / Q000473:pathology / Q000601:surgery*; D023421:Models, Animal; D008963:Molar / Q000473:pathology; D009532:Nickel; D010010:Osteoclasts / Q000473:pathology; D010027:Osteotomy / Q000379:methods*; D010513:Periodontal Ligament / Q000000981:diagnostic imaging / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D012391:Root Resorption / Q000209:etiology / Q000473:pathology; D013314:Stress, Mechanical; D000071681:Tartrate-Resistant Acid Phosphatase; D013997:Time Factors; D014025:Titanium; D014087:Tooth Movement Techniques / Q000009:adverse effects* / Q000379:methods; D014092:Tooth Root / Q000000981:diagnostic imaging / Q000473:pathology
C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D000071681:Tartrate-Resistant Acid Phosphatase
Corticision; Corticotomy; Tooth movement