Formaldehyde technique in dimensional stability of free fascia: an animal study

Despite the fact that this was a study done with fascia other than the temporalis, we found that non-formaldehyde-formed and formaldehyde-formed fascia graft shrunk by a mean value of 26.5% and 16.7%, respectively, which was statistically significant. This finding might be the explanation for the consistently reported successful outcomes in tympanoplasty carried out with formaldehyde-formed temporalis fascia. However, this study should be validated with autologous human temporalis fascia graft.

To determine whether there is any difference in the dimensional stability of free fascia grafts when formed with formaldehyde or not.

In a total of 22 rats, free fascias were prepared with 4% buffered formaldehyde solution in 11 and without formaldehyde in the other 11 rats. All fascia grafts of 1 x 1 cm were implanted under the insicion site of the same rat (autograft). All rats were re-operated after 5 days to measure the dimensions of the grafts. The postoperative changes in the dimensions were calculated.

By the 5th day, the mean non-formaldehyde-formed graft surface area was 73.51+/-13.43 mm(2) and the mean formaldehyde-formed graft surface area was 83.28+/-10.50 mm(2) respectively. After 5 days there was a mean decrease in surface area of the non-formaldehyde-formed and formaldehyde-formed grafts of 26.49+/-13.43 mm(2) and 16.72+/-10.50 mm(2), respectively. It was found that formaldehyde-formed fascia exhibited significantly superior dimensional stability when compared with non-fixed fascia during the 5 days of the early healing phase (p=0.031).