Tetracycline bone labeling: an improved technique using incident fluorescence.

A simple modification of the tetracycline bone labeling technique, based on the use of incident fluorescence, is introduced. The method has proven effective in the study of osteoneogenesis in bone grafts assisted by a soft tissue pedicle. The results obtained are highly specific, with new bone showing as a yellow band against blue background. The degree of fluorescence appears to be related to that of osteoneogenesis and correlates well with histological findings of the same specimens when examined by conventional light microscopy. The main advantages of this new technique over currently used methods are 1) avoidance of the time-consuming thinning procedure; 2) ability to study bone and surrounding soft tissue simultaneously; and 3) one-to-one comparison and documentation of the results of fluorescence and histological examination of the same specimen.