Assessment of the effects of citric acid and EDTA on cell viability of cultured human periodontal ligament cells attached to simulated avulsed permanent tooth using a spectrofluorometer-An in vitro study.

Background/aim: The delayed re-implantation of avulsed teeth results in ankylosis, followed by replacement resorption and eventual loss of the tooth within 2-4 years. To prevent tooth loss, the root surface can be etched with acid to expose the collagen fibers present in the cementum layer. This process facilitates normal reattachment and regeneration of the periodontal ligament. This in-vitro study aimed to assess the viability and number of attached cultured Human Periodontal Ligament Cells (HPLC) on the dehydrated root surface of simulated avulsed teeth treated with citric acid and EDTA solutions.

Materials and methods: Sound human permanent teeth were included in the study. The root portions of the teeth were sectioned into slices, air-dried for 1 h, and divided into the following three groups: Group A-control; Group B-Citric acid treated for 30 min; Group C-EDTA treated for 5 min. The slices were then placed in cultured HPLC. After a 24-h incubation period, the slices were visualized under the microscope and prepared for reading the viable and dead HPLC using a spectrofluorometer, as well as for counting HPLC in a Neubauer Chamber.

Results: The spectrofluorometer intensity for viable and dead HPLC showed a statistically significant difference (p = .003 and p = .002), with the mean intensity for viable HPLC greater in citric acid group (69.52 ± 74.51), followed by EDTA group (31.39 ± 9.12), and control group (-130.93 ± 30.99). The dead HPLC intensity was greater in the EDTA group (19.43 ± 47.31), followed by the citric acid group (1.28 ± 1.85), and the control group (-2.77 ± 0.76). The total number of cells in the Neubauer chamber showed a statistically significant difference (p < 0.001), with a higher count in the citric acid group (10.83 ± 4.08) followed by EDTA group (2.92 ± 2.92).

Conclusion: The application of citric acid for 30 min on the dehydrated root surface of avulsed teeth demonstrated superior outcomes compared to both EDTA treatment for 5 min and the control group.