The concentration of citric acid as dental root conditioner influences the behavior of fibroblasts from human periodontal ligament.

OBJECTIVE

This study investigated the behavior of fibroblasts from human periodontal ligament (hPLF) cultured on dental roots subjected to different protocols of citric acid conditioning.

MATERIALS AND

METHODS

32 human teeth extracted due to advanced periodontal disease provided 63 radicular fragments, which were randomly divided in groups according to the treatment given to the surface: rinsing with saline solution for 90 s (C), 10 % citric acid (CA10), or 50 % citric acid (CA50). The treatments were applied during 90 s, 120 s and 180 s (n = 9). hPLF were cultured for 24, 48 and 72 h (n = 3) on the treated samples and analyzed by scanning electron microscopy (SEM) for surface area covered by cells and dentinal tubules widening.

RESULTS

Excepting group C, all the other groups showed almost complete coverage of root surface by hPLF with time. At 24 h of cell culture, the largest area of coverage was seen in the samples treated with CA10-90 (98 ± 0.89 %) at 24 h of cell culture and this difference was significant (p < 0.05) in comparison to CA10-180 (84.04 ± 5.01 %), CA50-90 (63.28 ± 12.46 %), CA50-180 (56.59 ± 8.76 %) and C (0.06 ± 0.11 %). In all the other comparisons, there was no statistically significant differences between CA10 and CA50 (p > 0.05). Cells grown on surfaces treated with CA10 were more spread and flatten than in the CA50 specimens.

CONCLUSIONS

Periodontally compromised roots surfaces conditioned with 10 % citric acid for 90 s resulted in better substrate for hPLF proliferation, in initial periods of culture than 50 % citric acid. The enlargement of the dentinal tubules did not seem to be influenced by the acid concentration.