title: Therapeutic Effects of Sildenafil on Experimental Mandibular Fractures.
abstract: OBJECTIVE
  No previous studies have examined the effect of sildenafil on fracture healing. This study was designed to investigate the effect of sildenafil on the fracture healing process.
  
  
  METHODS
  Thirty-six female Sprague-Dawley rats (3-month-old) were used in this study. Animals were randomly divided into 2 groups based on treatment duration (1 week versus 4 weeks) and each group was then divided further into 2 subgroups, control (C) and study (S) groups. Group C (C1, C2) was treated daily with saline solution and group S (S1, S2) was treated daily with 10 mg/kg of sildenafil. Histologic, histomorphometric, radiological, and immunohistochemical analyses were performed at 1 week and 4 weeks after a fracture.
  
  
  RESULTS
  The sildenafil group showed a significant increase in fracture healing scores (P = 0.00). The authors observed a transition from fibrous callus to cartilage tissue and immature bone tissue in group S1; and an increased transition of cartilage tissue to completely immature bone tissue in group S2, both of which were administered sildenafil. The strong expression of bone morphogenetic protein 2 and col-1 was observed in the fibrous matrix and osteoblasts within areas of new bone formation, especially in group S1. This group also showed an increase in bone density measurements at 1 week that was statistically significant (P = 0.03).
  
  
  CONCLUSIONS
  Sildenafil accelerates fracture healing and can be used as a supporting factor in the improvement of fracture healing under various conditions.
authors.affiliation: *Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ondokuz Mayis University, Samsun†Department of Pathology, Faculty of Medicine, Gazi Osmanpaşa University, Tokat‡Department of Pathology, Faculty of Veterinary Medicine§Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Nilüfer
authors.initials: N
authors.lastname: Çakir-Özkan
authors.forename: Cihan
authors.initials: C
authors.lastname: Bereket
authors.forename: Ismail
authors.initials: I
authors.lastname: Sener
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Alici
authors.forename: Yonca Betil
authors.initials: YB
authors.lastname: Kabak
authors.forename: Mehmet Emin
authors.initials: ME
authors.lastname: Önger
mesh_terms: D000818:Animals; D015519:Bone Density; D004195:Disease Models, Animal; D005260:Female; D017102:Fracture Healing / Q000187:drug effects*; D008337:Mandibular Fractures / Q000175:diagnosis / Q000188:drug therapy*; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use; D011859:Radiography; D051381:Rats; D017207:Rats, Sprague-Dawley; D000068677:Sildenafil Citrate / Q000627:therapeutic use*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D000068677:Sildenafil Citrate