Treating Gingival Melanin Hyperpigmentation

Article in Review:

Esen E, Haytac MC, Oz IA, Erdoğan O, Karsli ED. Gingival melanin pigmentation and its treatment with the CO₂ laser. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2004; 98(5):522-527.

This article evaluates the use of the flexible fiber CO₂ surgical laser for treating Gingival Melanin Pigmentation, or GMP.  It concludes that using the CO₂ laser in SuperPulse mode is “an effective and safe method for the elimination of GMP [Gingival Melanin Pigmentation].”

Gingival melanin pigmentation treatment is a less documented procedure compared to other intra- and extra-oral cosmetic procedures for which flexible fiber CO₂ lasers have been successfully utilized for over two decades.

Often characterized by a purple-grey discoloration of the maxillary and / or mandibular gingiva, GMP constitutes a part of the growing field of intraoral soft tissue esthetics in dentistry.  Although melanin pigmentation of the gingiva may be completely benign and does not present a medical problem, gingival health and appearance are essential elements of an attractive smile (aesthetics).  The article notes that high levels of oral melanin pigmentation are most often observed in frequent smokers as well as individuals of African, East Asian or Hispanic ethnicity.

This study of using CO₂ laser surgery to treat GMP involved 10 patients (8 females and two males, 3 smokers and 7 non-smokers, 20 to 38 years of age).  All patients had GMP on the maxillary and mandibular buccal gingiva.  After incisional biopsies were performed, preoperative images taken, and patients’ areas of pigmentation measured, the melanin pigmented gingiva were ablated by CO₂ laser vaporization under local anesthesia.  The ablation was performed by a flexible fiber Luxar NovaPulse LX-20 SP surgical laser, the predecessor of LS-1005. The repeat A5 SuperPulse mode was applied at 10 watts, 20 Hz, 10 milliseconds, with a 0.8 mm spot size.  The remains of the ablated tissue were removed using sterile gauze dampened with saline.  This procedure was “repeated until the desired depth of tissue removal was achieved.”  To protect the adjacent teeth from the laser beam, either an acrylic template was used to cover the labial surface of the teeth, or an anodized periosteal elevator was gently placed in the gingival sulcus.

In addition, the more precise 0.4 mm laser tip was used at the gingival margins and interdental papilla; the power setting was also reduced to 5 watts in order to achieve better control and minimize risk of tooth damage (for more specifics on methods, warnings and post-operative care, see a full transcript of the article).

Not only was the ablation of the pigmented gingiva achieved without any bleeding, there was also no charring or carbonization during any of the procedures. None of the patients required repetition in the early postoperative period, and healing was completed in just 2 weeks, without any scar formation.  There were no infections or significant postoperative complications.  The final esthetic outcome – a considerable improvement – was “pleasant for all patients.”

In the discussion section of their report, the authors elaborate on several key topics.  First of all, in terms of pain management, they reiterate that local anesthesia should be applied for the depigmentation procedure, “since the pain and disturbance may hinder the complete removal of the pigmented gingiva.”  Furthermore, they examine the CO₂ laser wavelength and the settings that they used against preceding reports (on the treatment of GMP with laser)…

The authors note that, although Atsawasuwan et al. ^[1] reported successful results for the removal of GMP with the Nd: YAG laser, they also reported gingival fenestration 5 months after de-pigmentation.  This may be caused by the thermal effects of the Nd: YAG laser, Esen et al. state: “As the depth of thermal damage of the CO₂ laser extends from 50 to 100 µm, one may expect that application of CO₂ laser would be of lower risk to periosteum and underlying bone.”

The above idea is supported by the results of the Esen et al. report, where none of the patients encountered periosteal damage or gingival fenestration.

Last but certainly not least, while none of the patients in the Esen et al. report required repetition of the procedure, this result is contrary to the results of a study conducted by Nakamura et al. ^[2], in which a continuous wave CO₂ laser was used.  In that Nakamura et al. study, a total of 3 to 5 treatments were required, on a weekly basis, for complete removal of pigmented gingiva.  Thus, the one-time procedure with the superpulsed CO₂ laser may be advantageous, according to Esen et al., since “minimizing the carbonization provides an excellent visualization and controlled vaporization of the entire pigmented gingiva.”

In the CO₂ laser superpulsed mode, each pulse has high energy and is very short (as short as 70 µsec and always less than 800 µsec – a thermal relaxation time for the soft tissue is about 1,000 µsec). As a result, thermal damage to surrounding tissue is minimized, allowing for precise tissue removal and reduced healing time. Esen et al. also report that the superpulsed CO₂ laser’s precise tissue removal may be claimed as an advantage over cryosurgery, where “there can be difficulty in judging the final volume of tissue removal, which may result in recurrence and requirement for repeated procedures.”

Esen et al. sum up their report with the following statement: “considering the results of this study, it may be concluded that the application of superpulsed CO₂ laser appears to be a safe and effective alternative procedure for the treatment of gingival melanin pigmentation…”

References:

1. Atsawasuwan P, Greethong K, Nimmanon V. Treatment of gingival hyperpigmentation for esthetic purposes by Nd:YAG laser: report of 4 cases. J Periodontol 2000;71:315-21.
2. Nakamura Y, Hossain M, Hirayama K, Matsumoto K. A clinical study on the removal of gingival melanin pigmentation with the CO₂ laser. Lasers Surg Med. 1999;25:140-7.