Avaliação experimental dos efeitos da fixação interna (Ti, 1,5mm) no crescimento craniofacial pós-natal de coelhos, por meio de análise morfométrica direta

Abstract

In order to investigate the influence of internal rigid fixation on postnatal craniofacial growth, twenty rabbits were randomly divided into two groups - experimental and control. In the experimental group, in the seventh postnatal week, one 1.5-mm straight microplate was transversely fixed to the coronal cranial suture. In the control group, also in the seventh postnatal week, a microscrew was placed on each side of the righthand side of the coronal suture at a distance equal to that separating the outer holes of the microplate. All the animals were sacrificed, at the age of 24 weeks, in the 17th postoperative week and an evaluation of bone growth was performed using direct morphometric measurements of the anteroposterior distance in dry skulls. An anteroposterior shortening of the lambdoid frontal distance was observed, both by comparing the right and left sides in the same specimen and by comparing the same side in the two groups. The righthand side was found to be smaller in the experimental group. It is believed that internal rigid fixation through areas of rapid bone growth in the skulls of rabbits at the age of development is able to induce changes in the size of the skull.