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Updated: Nov 16, 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 with diode and Er,Cr:YSGG laser: evaluating re-pigmentation rate and patient perceptions
Walid Altayeb1, Omar Hamadah2, Bahaa Aldin Alhaffar3
1Department of Periodontology, Tamim Dental Polyclinic, P.O. Box 13876, Alwaab Street, Doha, Qatar. draltayeb@hotmail.com.
Objective:
To evaluate the efficiency of depigmentation, patient perceptions, and the recurrence rates of physiological gingival pigments during a 2-year follow-up after ablative depigmentation using two laser wavelengths: diode 940 nm and Er,Cr:YSGG 2780 nm.
Materials And Methods:
Sixty patients exhibiting physiological melanin hyperpigmentation in the buccal maxillary gingiva were randomly divided into two equal groups treated with an Er,Cr:YSGG laser at 2780 nm, and a 940 nm diode laser, respectively. The depigmentation procedure essentially involves the ablation of epithelial tissue exhibiting melanin pigmentation. The intensity and extensity indices of gingival pigments were evaluated at baseline, 1 month, 1 year, and 2 years.
Results:
At all time points following depigmentation treatment, oral pigmentation index (OPI) and melanin pigmentation index (MPI) scores were less significantly (p <0.05) compared to the baseline in both groups. Treatment was significantly faster with Er,Cr:YSGG laser and required no anesthesia, with faster healing and less postoperative discomfort after 1-week of treatment, compared to the diode laser treatment (p <0.001). The re-pigmentation intensity and extensity were higher significantly in the Er,Cr:YSGG group than in the diode group at 1 year and 2 years (p <0.05).
Conclusion:
Both lasers efficiently removed gingival pigments with comparable clinical outcomes and overall positive patient experience. Diode laser treatment exhibited better long-term stability of gingival color, with a lower incidence of re-pigmentation.
Clinical Relevance:
The color of the gingiva plays an important role in the esthetics of oral soft tissues and the overall ideal smile. Laser-assisted gingival depigmentation is an effective, comfortable, and reliable technique with good esthetical outcomes. The rate of re-pigmentation was affected by the laser wavelength and the technique used.

