title: Development of a behavior model of pain induced by experimental tooth movement in rats.
abstract: The mechanism of orthodontic pain and discomfort is poorly understood partly because of the limited number of animal behavioral models for pain assessment. This study aimed to develop a behavioral model for assessment of tooth-movement pain in rats using directed face-grooming activity. Male Sprague-Dawley rats weighing 200-300 g were used. They were videotaped on days 1, 3, 5, 7, and 14 after experimental tooth movement and their directed face-grooming behavior was evaluated. In addition, we also evaluated behavioral responses to the application of a progressively higher magnitude force and to multiple applications of an equal magnitude force. Finally, the effects of peripherally and systemically administered morphine and of the N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, on the behavioral responses were evaluated. The results indicated that time spent on directed face-grooming activity increased dramatically after initiating experimental tooth movement. The change concurred with the initial orthodontic pain response. This behavioral change was reproducible and was related to force magnitude. Application of both systemic and peripheral morphine and MK-801 could exert an analgesic effect on this pain model. These results suggest that directed face-grooming behavior can be a reliable measure for tooth-movement pain in rats, which could be widely used in investigating the orthodontic pain mechanism.
authors.affiliation: State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.forename: Jingqiu
authors.initials: J
authors.lastname: Hou
authors.forename: Zhihe
authors.initials: Z
authors.lastname: Zhao
authors.forename: Fan
authors.initials: F
authors.lastname: Jian
authors.forename: Peter
authors.initials: P
authors.lastname: Wamalwa
authors.forename: Wenli
authors.initials: W
authors.lastname: Lai
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Liao
mesh_terms: D000818:Animals; D003722:Dental Alloys; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000627:therapeutic use; D018691:Excitatory Amino Acid Antagonists / Q000627:therapeutic use; D005157:Facial Pain / Q000209:etiology* / Q000517:prevention & control; D006120:Grooming / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009020:Morphine / Q000627:therapeutic use; D009270:Naloxone / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000627:therapeutic use; D009294:Narcotics / Q000627:therapeutic use; D009532:Nickel; D009969:Orthodontic Wires; D010147:Pain Measurement; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D013314:Stress, Mechanical; D013997:Time Factors; D014025:Titanium; D014087:Tooth Movement Techniques / Q000009:adverse effects* / Q000295:instrumentation; D014743:Videotape Recording
chemical_list: D003722:Dental Alloys; D018691:Excitatory Amino Acid Antagonists; D009292:Narcotic Antagonists; D009294:Narcotics; D016194:Receptors, N-Methyl-D-Aspartate; C040654:titanium nickelide; D009270:Naloxone; D016291:Dizocilpine Maleate; D009020:Morphine; D009532:Nickel; D014025:Titanium