An experimental model in calvaria to evaluate bone therapies.

ABSTRACT

The clinical therapeutic application of experimental strategies requires extensive preclinical experimentation in appropriate animal models. Thus, a valid model must be established. The aim of the present study was to determine the critical size defect (CSD) of rat calvaria that is unable to undergo spontaneous bone regeneration. Forty Sprague Dawley female rats (body weight (bw) 250 +/- 20 g) were distributed in two groups. Circular surgical defects, 3 mm (Group A) and 5 mm (Group B) in diameter, were produced in the parietal bones. The animals were left untreated and sacrificed 1, 2, 3 and 6 weeks after surgery. Group A showed bone formation at the experimental site, increasing from 1 week (4.5