title: Adverse effects of the amlodipine on bone healing of the mandibular fracture: an experimental study in rats.
abstract: BACKGROUND
  Calcium channel blockers are effective antihypertensive agents, but they may affect many metabolic processes, including bone metabolism.
  
  
  OBJECTIVE
  The aim of this study was to evaluate by radiographic, histologic, and biochemical analyses the effects of amlodipine on bone healing of a defect simulating a fracture in mandibular ramus of rats.
  
  
  METHODS
  Fifty male Wistar rats were submitted to the same unilateral surgical procedure simulating a mandibular fracture. Experimental group received oral doses of amlodipine 0.04 mg/rat/day starting 12 days before procedure, while control group received water. Animals were sacrificed at 1, 7, 14, 30, and 90 days postoperatively. Numerical values were submitted to statistical analyses.
  
  
  RESULTS
  Radiographic analysis showed larger radiolucent area into bone defect to the experimental group at the periods of 14 (p = 0.016), 30 (p = 0.009), and 90 (p = 0.028) days. In the histological analysis, the experimental group had a slight delay in the chronology of the repair process. In the histomorphometric analysis, the experimental group presented significant lowering of newly formed bone volume at 7 and 14 days periods (p = 0.049). There was a significant decrease of alkaline phosphatase levels in experimental group in the initial periods (p = 0.049).
  
  
  CONCLUSIONS
  It was concluded that chronic use of amlodipine compromised bone neoformation in the repairing process of surgical defect in the mandibular ramus of rats, but no precluded occurrence of fracture consolidation.
authors.affiliation: Department of Maxillofacial Surgery, Prosthodontics and Traumatology, Dental School, University of São Paulo, São Paulo, São Paulo, Brazil. rbmoraes@usp.rbr
authors.forename: Rogério Bonfante
authors.initials: RB
authors.lastname: Moraes
authors.forename: Luciana
authors.initials: L
authors.lastname: Corrêa
authors.forename: João Gualberto Cerqueira
authors.initials: JG
authors.lastname: Luz
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D017311:Amlodipine / Q000633:toxicity*; D000818:Animals; D000959:Antihypertensive Agents / Q000633:toxicity*; D015519:Bone Density / Q000187:drug effects; D001861:Bone Regeneration / Q000187:drug effects; D001862:Bone Resorption / Q000473:pathology; D002121:Calcium Channel Blockers / Q000633:toxicity*; D017102:Fracture Healing / Q000187:drug effects*; D008297:Male; D008337:Mandibular Fractures / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D017311:Amlodipine; D000469:Alkaline Phosphatase