Effects of oestrogen deficiency and 17 beta-estradiol therapy on bone healing in calvarial critical size defects treated with bovine bone graft

Author(s)

de Almeida, Juliano Milanezi ^{[1, 2]} ; Bosco, Alvaro Francisco ^{[1, 2]} ; Faleiros, Paula Lazilha ^{[1, 2]} ; Cabrera Pazmino, Victor Fabrizio ^{[1, 2]} ; Murakawa, Ana Cristina ^{[1, 2]} ; Bonfante, Samara ^{[1, 2]} ; Hitomi Nagata, Maria Jose ^{[1, 2]} ; Garcia, Valdir Gouveia ^{[1, 2, 3]}

Affiliation

^[1] Univ Estadual Paulista, UNESP, Dept Surg, Div Periodont, BR-16015050 Sao Paulo - Brazil

^[2] Univ Estadual Paulista, UNESP, Integrated Clin, Dent Sch Aracatuba, BR-16015050 Sao Paulo - Brazil

^[3] Univ Ctr Educ Fdn Barretos UNIFEB, Dent Sch Barretos, Dept Periodont, BR-14783226 Sao Paulo - Brazil

• Document type: Journal article
• Source: ARCHIVES OF ORAL BIOLOGY; v. 60, n. 4, p. 631-641, APR 2015.
• Web of Science Citations: 5

Abstract

Objective: To histomorphometrically analyze the effect of ovariectomy-induced oestrogen deficiency and 17 beta-estradiol therapy on bone healing of surgically created critical-size defects (CSDs) treated with bovine bone graft (BBG). Methods: Forty-eight female rats were randomly assigned to the following 3 experimental groups (n = 16): sham-operated animals (SHAM), ovariectomized animals (OVX) and ovariectomized animals treated with oestrogen (OVX+E2). OVX+E2 animals received daily subcutaneous injections of 17 beta-estradiol (20 mu g/kg) from 8 days after ovariectomy until euthanasia. Thirty days after the surgery, an 8 mm CSD was surgically created in each calvaria of all animals and filled with BBG. Animals were euthanized at either 30 or 60 days postoperative. A histological analysis, percentage of Newly Formed Bone Area (NFBA), osteoblast and osteoclast number was histomorphometrically performed (p <= 0.05). Results: At 30 days, SHAM group (8.82% +/- 2.93) had significantly greater NFBA than OVX (4.66% +/- 1.35) and OVX+E2 groups (5.85% +/- 4.08) (p <= 0.05). At 60 days, SHAM group (11.51% +/- 3.08) and OVX+E2 group (9.84% +/- 1.87) had significantly greater NFBA than OVX animals (5.12% +/- 0.68) (p <= 0.05). Fewer osteoblasts were observed in the OVX group at 30 (763.40 +/- 121.60) and 60 (696.60 +/- 80.92) days than in the SHAM group at 30 days (1356.00 +/- 95.38). Fewer osteoclasts were observed in the OVX+E2 group (3.25 +/- 2.16) than in the SHAM (9.75 +/- 1.82) and OVX (12.75 +/- 1.47) groups at 30 days (p <= 0.05). Conclusions: Oestrogen deficiency compromises bone healing in calvarial CSDs treated with BBG in ovariectomized rats. After 60 days post-surgery, 17 beta-estradiol therapy improved bone healing in calvarial CSDs treated with BBG in ovariectomized rats. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 08/04895-4 - INFLUENCE OF OVARIECTOMY AND THERAPIES WITH ESTROGEN AND ALENDRONATE IN THE PROCESS OF REPAIR OF CRITICAL SIZE DEFECTS WITH HETEROGEN BONE GRAFTS. HISTOMORPHOMETRIC STUDY IN RATS CALVARIA.
• Grantee: Paula Lazilha Faleiros
• Support Opportunities: Scholarships in Brazil - Scientific Initiation