Bone turnover assessment after bisphosphonate treatment cessation.

• Grant number: 09/16617-1
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2010
• End date: February 29, 2012
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Silvana Regina Perez Orrico
• Grantee: Silvana Regina Perez Orrico
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

This study will be aimed in the evaluation of the period of time after the cessation of the bisphosphonate therapy necessary to the reestablishment of the bone turnover. Seventy rats will be divided into 2 groups: control group (n = 10) and test group (n = 60). The control group will receive weekly subcutaneous injections of a placebo while the test group, alendronate once a week. After 90 days the treatment will be suspended in 50 animals. Ten animals of the test group will keep receiving alendronate during the whole experimental period. The control group, the animals that will be continuing the therapy and 10 animals of the test group will receive a titanium implant on left tibia metaphysis one day after the last dose of the 90 days treatment (Day 0). The test group animals will also receive an implant at days 7, 14, 28 and 45 after drug discontinuation. All animals will be euthanized 28 days after the implant placement. At the day that the implant will be installed and the sacrifice day blood and urine samples will be collected to the evaluation of bone formation (osteocalcin) and bone resorption markers (deoxypyridinoline and CTX). The femur and lumbar vertebrae will be analyzed for bone mineral density. Specimen containing the implant will be evaluated for static and dynamic histological parameters of bone formation. (AU)