title: Effect of Beta-Blockers on Number of Osteoblasts and Osteoclasts in Alveolar Socket Following Tooth Extraction in Wistar Rats.
abstract: BACKGROUND
  Various researchers have suggested the use of β2-adrenergic receptor antagonists in prevention or treatment of bone resorption.
  
  
  OBJECTIVE
  This study aimed to evaluate the effect of β2-adrenergic receptor antagonists on number of osteoclasts and osteoblasts involved in the healing of extraction socket of maxillary first molar in rats.
  
  
  METHODS
  Maxillary first molars of 40 rats were extracted and divided into two groups. The test group received 0.1 mg/kg propranolol intraperitoneally daily. The controls received normal saline. At days 7, 14, 21 and 28 post-extraction, 5 rats were euthanized from each group. Maxillary bone was resected and the mean number of osteoblasts and osteoclasts in tooth socket was measured.
  
  
  RESULTS
  After 1 week, the number of osteoclasts in the controls was significantly higher than the test group. A significant increase in the number of osteoclasts in both groups at week 1 was observed compared to the following weeks (p< 0.05). The number of osteoblasts in the controls at second week reached its maximum rate but stayed constant in the 3rd and 4th weeks. Osteoblasts in the test group increased similar to the controls but reached its maximum at 3rd week and showed a significant increase compared to the controls (p< 0.05).
  
  
  CONCLUSIONS
  β2 adrenergic receptor antagonists decrease the number of osteoclasts and increase the number of osteoblasts during extraction socket healing.
authors.affiliation: Dept. of Prosthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Katayoun
authors.initials: K
authors.lastname: Sadr
authors.affiliation: Dept. of Oral and Maxillofacial Pathology, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Amirala
authors.initials: A
authors.lastname: Aghbali
authors.affiliation: MD, PhD of Anatomy, Tracheal Diseases Research Center, National Research Institute of Tuberculosis and Lung Disease, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Makan
authors.initials: M
authors.lastname: Sadr
authors.affiliation: Dept. of Prosthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Hamed
authors.initials: H
authors.lastname: Abachizadeh
authors.affiliation: PhD Student of Anatomy, Dept. of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Azizi
authors.affiliation: Doctor of Veterinary Medicine, Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mehran
authors.initials: M
authors.lastname: Mesgari Abbasi
keywords:  Alveolar bone ;  Osteoblast ;  Propranolol ;  Rat; Osteoclast 