A 27-year-old Caucasian female was referred to the Stomatology and Dental Medicine Department (CESPU) of the Centro Hospitalar de São João, Pólo de Valongo, Oporto, Portugal. Her chief complaint was of a “dark-colour lower gum” and she made the request for rapid cosmetic therapy. She reported noticing darkening of the teeth and gums for over two years, mainly in the mandible. No symptoms and no significant personal or family history were present. The patient denied taking any medication or any other dark pigmentation in other locations. Her blood pressure was within the normal range of values. She had stopped smoking a year before the consultation, although she had smoked 30 cigarettes per day for more than 10 years. On oral examination two black-brown macules measuring 1 × 1 cm were detected in the vestibular attached lower gingiva (). There was no lymphadenopathy or salivary gland abnormalities detected. Previous incisional biopsy to rule out any malignancy and blood investigations (complete full blood count and general biochemistry, including cortisol and ACTH serum levels) showed no abnormalities or potential causes. A diagnosis of smoker's melanosis was given based on the smoking history and the absence of any abnormalities seen in previous investigations. After explaining the benign character of the pigmentation, the patient requested the elimination of the pigmentation by aesthetic reasons due to professional work issues. A CO2 laser vaporization for gingival depigmentation was proposed. The vaporization of the pigmentation was performed under local anaesthesia (2% lidocaine with 1 : 100,000 epinephrine) with CO2 laser (10600 nm) (DEKA Smart US20D, Florence, Italy), with angulated mirror, focus spot of 1 mm, pulsed mode (50 Hz), 4.5 W of output power, power density of 573.25 W/cm2, and fluence of 11.46 J/cm2 (). During this procedure, safety precautions were in place to protect the operator, assistant, and patient. With this laser procedure, the secondary-intention healing of the surgical wound was reached without any dressing (). Paracetamol (1 g every 12 hours) was prescribed for two days to be taken only if she developed painful symptoms. After 3 weeks, wound healing was completed uneventfully without any melanin pigmentation (). She did not report any postoperative pain, swelling, or other complications. After two years of follow-up, the patient had no symptoms or signs of gingival melanin pigmentation.
A 22-year-old nonsmoking patient of brown race was referred to the department of oral medicine and surgery at the University Dental Clinic of Monastir, with a chief complaint of a “dark-color upper gum.” He reported noticing darkening of the gums 10 years ago. The lesion was asymptomatic and has remained stable since then. He had no significant personal history and denied taking any medication or other substances that may have caused this pigmentation.\nIn clinical examination, periodontal tissues were healthy, but bilateral melanin pigmentation was present, associated with a fractured upper central incisor. A pigmentation index as mentioned by Kumar et al. [] was used to determine the level of pigmentation, and the score was diagnosed as “3” (diffuse brown to black pigmentation, marginal, and attached) ().\nAt first sight, the diagnoses evoked by this oral pigmentation of melanin were gingival pigmentation of exogenous origin (drugs, tobacco, metals,…), racial pigmentation, and Addison's disease. However, given the diffuse, bilateral appearance of these pigmentations which are not of recent appearance, the absence of smoking history or drug use, the patient's race, and the absence of systemic involvement, a final diagnosis of physiological gingival pigmentation (ethnic/racial) was established.\nFollowing the patient's request, a laser depigmentation procedure was planned after obtaining the patient's consent.\nA semiconductor diode surgical laser unit (Elexxion pico 808 nm diode laser, Elexxion AG, Singen, Germany) was used for the procedure; it is a digitally pulsed diode laser with a frequency of 20,000 Hz, a peak power of 5 W, and a pulse width of 26 microseconds. With this setting, the laser beam is “on” the tissue for only 26 microseconds which makes around one-third of the total cycle. The rest of the time is to allow the tissue to cool down. The semiconductor diode laser was operated in a contact method using a 400 nm flexible fiber optic handpiece.\nSpecial eyeglasses were worn by the patient and the staff to fulfill the Food and Drug Administration laser safety rules. After a local infiltration of anesthesia, the properly initiated tip of the diode laser was angled at an external bevel of 45 degrees. The melanin-pigmented gum was resected by circular movement of the fiber with a slight contact on the tissue, avoiding teeth structures.\nThis technique was performed on the entire pigmented anterosuperior attached gingiva for the deepithelialization procedure. Saline-soaked gauze was used to remove epithelial remnant. This procedure was repeated until the desired depth of tissue removal was reached, combined with a labial frenectomy (). The treatment time was two minutes compared to the ablative technique time up to 30 minutes in an area of first molar to first molar.\nAnalgesics and 0.2% chlorhexidine mouthwash were prescribed.\nThe patient did not report any postoperative pain, swelling, or other complications at the first and subsequent visits. It should be noted that a greyish-white fibrin layer completely covers the “laser wound” 6 hours after the operation (), which should not be misinterpreted as secondary infection. Four months later, the patient had no symptoms or signs of gingival melanin pigmentation ().