Dermatology Online Journal

Amalgam tattoo
Hien T Tran MD PhD, Niroshana Anandasabapathy MD PhD, Anthony C Soldano MD
Dermatology Online Journal 14 (5): 19

Department of Dermatology, New York University

---

Abstract

A 53-year-old woman with a history of melanoma status-post excision two years prior presented with a 4-month history of 4 dark-brown macules on the inferior surface of her tongue. A biopsy specimen showed a squamous mucosa with chronic submucosal inflammation and brown pigment. The clinical and histopathologic findings were consistent with a diagnosis of amalgam tattoo. Amalgam tattoos are common, oral pigmented lesions that clinically present as isolated, blue, grey, or black macules on the gingivae, the buccal and alveolar mucosae, the palate, and/or the tongue. They are due to deposition of a mixture of silver, tin, mercury, copper, and zinc, which are components of an amalgam filling, into the oral soft tissues. Amalgam tattoos can either be treated surgically or with a Q-switched ruby laser. In the case of our patient with the history of melanoma, her oral lesions proved not to be the more dire diagnosis of malignant melanoma.

---

Clinical synopsis

A 53-year-old woman with a history of melanoma status-post excision 2 years prior presented to the Dermatology Clinic at Bellevue Hospital Center with a 4-month history of 4 dark-brown macules on the inferior surface of her tongue. The patient reported that the lesions were non-painful, that they had never bled, and that she had not suffered trauma to this area. The review of systems was unremarkable. The patient also had also been seen in the Ear Nose and Throat Clinic at Bellevue Hospital Center prior to being evaluated in the Dermatology Clinic, where the pigmented lesions were thought to be varicosities. The lesions were not biopsied at that time. The patient was not taking any medications but was taking multivitamins.

The patient was refered to oral surgery for a biopsy of the pigmented macule on the inferior surface of the tongue.

Physical Examination

Four dark-brown macules that measured 2- to 3-mm in size were present. The largest was located to the right of the frenulum. Two additional lesions were located on either side of the frenulum, and the fourth smaller lesion was located postero-lateral to the most lateral right-sided lesion.

Figure 1	Figure 2

A complete blood count, metabolic panel, hepatic panel, and lipid panel were normal.

Histopathology

In the lamina propria there is a finely granular black/brown pigment that encases elastic fibers and the basement membrane of superficial capillaries; it is within the cytoplasm of histiocytes.

Comment

Amalgam tattoos are common oral pigmented lesions that clinically present as isolated, blue, grey, or black macules on the gingivae, the buccal and alveolar mucosae, the palate, and/or the tongue. They are due to deposition of a mixture of silver, tin, mercury, copper, and zinc, which are components of an amalgam filling, into the oral soft tissues [1, 2, 3]. The deposition occurs after a number of different dental procedures that include diffusion through soft tissues from root-end fillings, accidental deposition of fine metallic particles into the gingiva by high-speed drills, accidental abrasion of the mucosa by high-speed rotary instruments, or deposition of amalgam scraps left behind during extraction [4, 6].

These tattoos do not represent a health hazard since the mercury present in amalgam is not in a free state [5, 6]. However, owing to its clinical appearance, amalgam tattoos can be mistaken for a number of different conditions of concern, such as melanoma, pigment-cell nevi, melanotic macules, melanoacanthoma, Kaposi's sarcoma, and physiologic pigmentation [7]. The diagnosis is more easily determined if the lesion is in the vicinity of a large silver amalgam restoration or a gold crown. If not, a biopsy may be performed. Histopathologic features include discrete, fine, dark granules and irregular, solid fragments. They can be found along collagen bundles and vessels and also are found within macrophages, mulinucleated giant cells, fibroblasts, and endothelial cells [8].

Treatment for amalgam tattoos was originally limited to surgery with grafting of mucosa or gingiva over the previous site of the tattoo [9, 10]. Advances in laser technology now allow amalgam tattoos to be removed by the Q-switched ruby laser [5, 6]. It is believed that the lasers shatter the tattoo particles that are then removed by the lymphatics or transepidermal extrusion.

References

1. Weathers DR, Fine RM. Amalgam tattoo of the oral mucosa. Arch Dermatol 1974; 110:727

2. Mirowski GW, Waibel JS. Pigmented lesions of the oral cavity. Dermatol Ther 2002; 15: 218

3. Buchner A, Hansen LS. Amalgam pigmentation (amalgam tattoo) of the oral mucosa: a clinicopathologic study of 268 cases. Oral Surg Oral Med Oral Pathol 1980; 49:139

4. Pigatto PD, et al. Amalgam tattoo: a close-up view. J Eur Acad Dermatol Venereol 2006; 20:1352

5. Ashinoff R, Tanenbaum D. Treatment of an amalgam tattoo with the Q-switched ruby laser. Cutis 1994; 54:269

6. Shah G, Alster TS. Treatment of an amalgam tattoo with a Q-switched Alexandrite (755 nm) laser. Dermatol Surg 2002; 28:1180

7. Martin JM, et al. An amalgam tattoo on the oral mucosa related to a dental prosthesis. J Eur Acad Dermatol Venereol 2005; 19:90

8. McGinnis JP, et al. Amalgam tattoo: report of an unusual clinical presentation and the use of energy dispersive x-ray analyses as an aid to diagnosis. J Am Dent Assoc 1985; 110:52

9. Dello-Russo NM. Esthetic use of a free gingival autograft to cover an amalgam tattoo: report of a case. J Am Dent Assoc 1981; 102:334

10. Shiloah J, et al. Reconstructive mucogingival surgery: the management of amalgam tattoo. Quintess Int 1988; 19:489

© 2008 Dermatology Online Journal