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Updated: Dec 26, 2025

In Vitro Evaluation of The Effects Of Er,Cr:YSGG and Diode Lasers Used on Titanium Cylinder
Published on: June 6, 2025
Gingival depigmentation by Er,Cr:YSGG laser and diode laser: a split mouth, clinical trial study
Mahin Bakhshi1, Seyed Masoud Mojahedi2, Mohammad Asnaashari3
1Oral Medicine Department. School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Background And Aims:
The Aim of this study was to evaluate the effectiveness of Diode laser and Er,Cr:YSGG laser ablation on the treatment of physiologic gingival melanin hyperpigmentation.
Materials And Methods:
This research design was split mouth, double blind, and clinical trial. The power of the diode laser was set at 1 W, fiber 320 µ, irradiation mode: continuous-wave with treatment mode of contact tip and Er,Cr:YSGG laser (2780 nm) was set at 100 MJ, frequency of 15 Hz, total power of 1.75 W, 10% water and 20% air. Bleeding, pain, healing, Dummett oral pigmentation index (DOPI) and Hedin melanin score changes and repigmentation were assessed. Patients were followed for 6 months.
Results:
A total number of 14 patients were involved in this study. There were statistically significant differences in reduction of DOPI and Hedin melanin score in each treatment groups separately while diode laser group had better results (P < 0.0001). There was no statistically significant difference between groups in terms of repigmentation. There was more pain in diode laser group (P < 0.0001) and there was more bleeding in Er,Cr:YSGG laser group (P = 0.0156). Gingival healing was more in Er,Cr:YSGG laser group (P < 0.0001).
Conclusion:
Diode laser had more efficiency for reduction of DOPI and Hedin melanin index scores.

