title: Influence of estrogen deficiency and its treatment with alendronate and estrogen on bone density around osseointegrated implants: radiographic study in female rats.
abstract: OBJECTIVE
  This study evaluated the influence of estrogen deficiency and its treatment on bone density around integrated implants.
  
  
  METHODS
  Implants were placed in female rat tibiae. The animals were assigned to 5 groups: control, sham, ovariectomy, estrogen, and alendronate. The control group was humanely killed to confirm integration of the implant. The others were submitted to ovariectomy or sham surgery. Bone density was measured by digital radiographs at 6 points on sides of the implant.
  
  
  RESULTS
  The analysis of radiographic bone density revealed estrogen privation had a negative impact only in the cancellous bone. The estrogen group differed significantly (P < .05) from the ovariectomy and alendronate groups. The alendronate group presented the highest density for all evaluated regions.
  
  
  CONCLUSIONS
  Ovariectomy caused a decrease in the radiographic bone density in the cancellous region. Estrogen replacement therapy and alendronate were effective treatments in preventing bone mass loss around integrated implants.
authors.affiliation: Department of Oral Diagnosis and Surgery, School of Dentistry of Araraquara, UNESP-São Paulo State University, São Paulo, Brazil. gabriela_giro@terra.com.br
authors.forename: Gabriela
authors.initials: G
authors.lastname: Giro
authors.forename: Daniela
authors.initials: D
authors.lastname: Gonçalves
authors.forename: Celso Eduardo
authors.initials: CE
authors.lastname: Sakakura
authors.forename: Rosa Maria Rodrigues
authors.initials: RM
authors.lastname: Pereira
authors.forename: Elcio
authors.initials: E
authors.lastname: Marcantonio Júnior
authors.forename: Silvana Regina Perez
authors.initials: SR
authors.lastname: Orrico
mesh_terms: D015502:Absorptiometry, Photon; D019386:Alendronate / Q000008:administration & dosage*; D016301:Alveolar Bone Loss / Q000209:etiology* / Q000517:prevention & control; D000704:Analysis of Variance; D000818:Animals; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D015921:Dental Implants; D004958:Estradiol / Q000008:administration & dosage*; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000008:administration & dosage* / Q000172:deficiency*; D005260:Female; D007279:Injections, Subcutaneous; D016348:Osseointegration / Q000187:drug effects*; D010024:Osteoporosis / Q000150:complications / Q000517:prevention & control; D010052:Ovariectomy / Q000009:adverse effects; D010053:Ovary / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric; D013977:Tibia
chemical_list: D050071:Bone Density Conservation Agents; D015921:Dental Implants; D004967:Estrogens; D004958:Estradiol; D019386:Alendronate