title: Effects of short-term acetaminophen and celecoxib treatment on orthodontic tooth movement and neuronal activation in rat.
abstract: Non-steroidal anti-inflammatory drugs (NSAIDs) have been used for pain relief in orthodontics, but clinical studies reported that they may reduce tooth movement (TM). By other side, TM seems to activate brain structures related to nociception, but the effects of NSAIDs in this activation have not been studied yet. We analyzed the effect of short-term treatment with acetaminophen or celecoxib in the separation of rat upper incisors, as well as in neuronal activation of the spinal trigeminal nucleus, following tooth movement. Thirty rats (400-420 g) were pretreated through oral gavage (1 ml/dose) with acetaminophen (200mg/kg), celecoxib (50mg/kg) or vehicle (carboxymethylcellulose 0.4%). After 30 min, they received an activated (30 g) orthodontic appliance for TM. In controls, this appliance was immediately removed after its introduction. Rats received ground food, and every 12h, one of the drugs or vehicle. After 48 h, they were anesthetized, maxilla was radiographed, and were perfused with 4% paraformaldehyde. Brains were further processed for Fos immunohistochemistry. TM induced incisor distalization (p<0.05) and neuronal activation of the spinal trigeminal nucleus. Treatment with both drugs did not affect tooth movement, but reduced c-fos expression in the caudalis subnucleus. No changes in c-fos expression were seen in the oralis and interpolaris subnuclei. We conclude that neither celecoxib nor acetaminophen seems to affect tooth movement, when used for 2 days, but both drugs are able to reduce the activation of brain structures related to nociception. Short-term treatment with celecoxib, thus, may be a therapeutic alternative to acetaminophen when the latter is contraindicated.
authors.affiliation: Departamentos de Morfologia, Estomatologia e Fisiologia, Universidade de São Paulo, Avenida do Cafe s/n, 14040-904 Ribeirão Preto, SP, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Stabile
authors.forename: M B S
authors.initials: MB
authors.lastname: Stuani
authors.forename: C R A
authors.initials: CR
authors.lastname: Leite-Panissi
authors.forename: M J A
authors.initials: MJ
authors.lastname: Rocha
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D000068579:Celecoxib; D015870:Gene Expression / Q000187:drug effects; D007150:Immunohistochemistry; D007180:Incisor; D008297:Male; D008437:Maxilla / Q000000981:diagnostic imaging / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D011720:Pyrazoles / Q000494:pharmacology*; D011859:Radiography; D051381:Rats; D017208:Rats, Wistar; D013449:Sulfonamides / Q000494:pharmacology*; D014087:Tooth Movement Techniques; D014279:Trigeminal Nucleus, Spinal / Q000187:drug effects* / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016760:Proto-Oncogene Proteins c-fos; D011720:Pyrazoles; D013449:Sulfonamides; D000082:Acetaminophen; D000068579:Celecoxib