Effects of alendronate on bone healing after tooth extraction in rats.
OBJECTIVE
Tooth extraction has been identified as an important risk factor for bisphosphonate-induced osteonecrosis of the jaw. Therefore, the main goal of this study was to determine the effects of alendronate on healing of the extraction socket and on interdental alveolar bone after tooth extraction in rats.


METHODS
Animals were injected subcutaneously with vehicle or alendronate for 3-4 weeks before the first mandibular molar was extracted and these treatments were continued during post-extraction periods of 10, 21, 35 and 70 days. Mandibles were processed to evaluate healing of the extraction socket and adjacent alveolar bone by assessing bone formation, bone resorption and vascularity by histomorphometric techniques.


RESULTS
Alendronate decreased new woven bone formation, blood vessel area, perimeter and number in the extraction socket at 10 days postextraction, but not at later time points. Furthermore, alendronate-treated rats had increased interdental alveolar bone volume and height only at 10 days postextraction. In addition, a 2.5-fold increase in the percentage of empty osteocyte lacunae was found in alveolar bone of alendronate-treated rats only at 10 days postextraction.


CONCLUSIONS
Alendronate transiently decreases bone formation and vascularity in the extraction socket and delays the removal of interdental alveolar bone after tooth extraction in rats.
Aguirre
J I
JI
Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA. aguirrej@ufl.edu
Altman
M K
MK
Vanegas
S M
SM
Franz
S E
SE
Bassit
A C F
AC
Wronski
T J
TJ
D019386:Alendronate / Q000008:administration & dosage / Q000627:therapeutic use*; D000539:Alveolar Process / Q000098:blood supply / Q000187:drug effects; D000818:Animals; D001808:Blood Vessels / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001857:Bone Matrix / Q000098:blood supply / Q000187:drug effects; D001862:Bone Resorption / Q000473:pathology / Q000517:prevention & control; D005260:Female; D007279:Injections, Subcutaneous; D008334:Mandible / Q000098:blood supply / Q000187:drug effects / Q000601:surgery; D008963:Molar / Q000601:surgery; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010006:Osteoblasts / Q000187:drug effects; D010010:Osteoclasts / Q000187:drug effects; D010011:Osteocytes / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014081:Tooth Extraction; D020390:Tooth Socket / Q000098:blood supply / Q000187:drug effects* / Q000601:surgery; D014945:Wound Healing / Q000187:drug effects
D050071:Bone Density Conservation Agents; D019386:Alendronate