Effect of radiotherapy on the chemical composition of root dentin

Abstract

Background

The radiotherapy can directly affect the bond strength of the adhesive materials, interfering in the prognosis of restorative treatments, which may be caused by chemical changes in dentin structure.

Methods

Twenty inferior homologues premolars were distributed in 2 groups (in vitro study) (n = 10): nonirradiated and irradiated. The specimens were submitted to the analysis of phosphate (ν₁PO₄³⁻;ν₂PO₄³⁻;ν₄PO₄³⁻), carbonate (ν₃CO₃²⁻), amide I, CH₂, amide III, and amide I/III ratio by confocal Raman spectroscopy. Data were submitted to statistical analysis (T test, P < .05).

Results

In intracanal dentin, the irradiated group had lower ν₄PO₄³⁻ values (1.23 ± 0.06) compared to nonirradiated group (1.40 ± 0.18) (P < .05), with no difference for ν₁PO₄³⁻ and ν₂PO₄³ peaks (P > .05). The irradiated (1.56 ± 0.06) had lower carbonate, amide III (1.05 ± 0.19), and amide I/III ratio values (0.19 ± 0.06) compared to nonirradiated group (1.42 ± 0.10, 1.28 ± 0.24, and 0.31 ± 0.10, respectively) (P < .05). For medium dentin irradiated group (1.30 ± 0.12) had lower phosphate values compared to nonirradiated group (1.48 ± 0.22) (P < .05). In cementum, there was no statistical difference between the groups.

Conclusion

The radiotherapy was able to cause changes in ν₄PO₄³⁻, carbonate, and amide III peaks of root dentin.

https://ift.tt/2zZElky