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CASE REPORT Table of Contents   
Year : 2005  |  Volume : 16  |  Issue : 4  |  Page : 171-176
Treatment of gingival pigmentation : A case series

Department of Periodontics, J.S.S. Dental College & Hospital, S.S Nagar, Bannimantap, Mysore 570015, Karnataka, India

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A smile expresses a feeling of joy, success, sensuality, affection and courtesy, and reveals self confidence and kindness. The harmony of the smile is determined not only by the shape, the position and the color of the teeth but also by the gingival tissues. Gingival health and appearance are essential components of an attractive smile. Gingival pigmentation results from melanin granules, which are produced by melanoblasts. The degree of pigmentation depends on melanoblastic activity. Although melanin pigmentation of the gingiva is completely benign and does not present a medical problem, complaints of 'black gums' are common particularly in patients having a very high smile line (gummy smile). For depigmentation of gingiva different treatment modalities have been reported like- Bur abrasion, scraping, partial thickness flap, cryotherapy, electrosurgery and laser. In the present case series bur abrasion, scraping, partial thickness flap (epithelial excision) cryotherapy and electrosurgery have been tried for depigmentation, which are simple, effective and yield good results, along with good patient satisfaction. The problems encountered with some of these techniques have also been discussed.

Keywords: Bur abrasion, epithelial excision, electrocautery, cryotherapy, depigmentation

How to cite this article:
Prasad D, Sunil S, Mishra R, Sheshadri. Treatment of gingival pigmentation : A case series. Indian J Dent Res 2005;16:171-6

How to cite this URL:
Prasad D, Sunil S, Mishra R, Sheshadri. Treatment of gingival pigmentation : A case series. Indian J Dent Res [serial online] 2005 [cited 2023 Jun 6];16:171-6. Available from:

   Introduction Top

A smile expresses a feeling of joy, success, sensuality, affection and reveals self-confidence and kindness. A smile is more than a method of communication and is a means of socialization and attraction. The harmony of the smile is determined not only by the shape, the position and the color of the teeth but also by the gingival tissues [1]. Gingival health and appearance are essential components of an attractive smile. Oral melanin pigmentation is well documented in the literature and is considered to be multifactorial, whether physiological/pathological and can be caused by a variety of local and or systemic factors (Durnmet, 1979) including genetic, tobacco use, prolonged administration of certain drugs especially antimalarial agents and tricyclic antidepressants [2].

The gingiva is most commonly affected intraoral tissue responsible for an unpleasant appearance. Melanin pigmentation often occurs in the gingiva as a result of an abnormal deposition of melanin. This pigmentation may be seen across all the races [3] and at any age [4] and it is without gender predilection [5]. It is generally agreed that pigmented areas are present only when melanin granules synthesized by melanocytes are transferred to the keratinocytes. This close relationship between melanocytes and keratinocytes was labeled by Fitzpatrick and Breathnach (1963) as the epidermal-melanin unit [6].

Although melanin pigmentation of the gingiva is completely benign and does not present a medical problem, complaints of black guns are common particularly in patients having a very high smile line (gummy smile).

The smile lines can be analyzed according to the following classification -

Class 1 . Very high smile line -more than 2 mm of the marginal gingiva visible or more than 2 rnm apical to the cemento-enamel junction visible for the reduced but healthy periodontium. This could be gimmry smile.

Class2 . High smile line - between 0 and 2 rnm of marginal gingiva visible or between 0 and 2 mm apical to the cemento-enamel junction visible for the reduced but healthy periodontium.

Class3 . Average smile line- only gingival embrasures visible.

Class4 . Low smile line- gingival embrasures and cemento-enamel junction not visible[1].

Demand for depigmentation is usually made for esthetic reasons, particularly in patients having a very high or high smile line. However there is not much information in the literature about depigmentation of gingiva. Elimination of these melanotic areas through surgery [7], [8], lasers [5], [9], cryosurgery through use of a gas expansion system [10], bur abrasion, scrapping and electrocautery have been reported by many authors (Hirschfeld and Hirschfeld 1951, Durnmet and Bolden 1963, Ginwalla et al 1966, Manchandia 1979, Tal et al 1987 and Atsawasuwan and Coworkers 2000). Each technique has its own advantages and inadequacies. Hirschfeld and Hirschfeld (1951) used phenol (90%) and alcohol (95%) to remove areas of oral pigmentation by destroying tissue down to and slightly below the basal layer of the mucous membranes. Repigmentation soon developed in three patients; the rest of the subjects met with the same results a short while later. Durnmett and Bolden (1963) operated pigmented gingiva by gingivectomy procedure in 9 cases. Repigmentation occurred in 67% of the areas, as early as 33 days after surgical removal. Ginwalla et al (1966) attempted to remove gingival pigmentation in 6 cases using three different techniques:

Slicing, Bone denudation and abrasion Tal et al (1987) described depigmentation of the gingiva by cryosurgery, using gas expansion cryosurgical system based on the Joule-Thomson effect. Trelles et al (1993) were the firstto treat patients with pigmented gingiva by argon laser. Chin-Jyh Yeh (1998) described cryosurgical treatment of melanin-pigmented gingiva using direct application of liquid nitrogen (-1960°C) with a cotton swab to the pigmented gingiva.

The present case series describes three simple and effective surgical depigmentation techniques - Bur abrasion/scraping, partial thickness flap and electrosurgery for gingival depigmentation, which are simple, effective and have produced good results with patient satisfaction. It also describes the cryotherapy method and its inherent problems.

   CASE 1 Top

A 23year old female patient complaining of heavily pigmented guns visited department of Periodontics, J.S.S. Dental College and Hospital, Mysore. On examination, the patient had a very high smile line that revealed the deeply pigmented gingiva from second premolar to second premolar [Figure - 1]. Pigmentation was unsightly and hence depigmentation procedures were planned.

The patient was given oral hygiene instructions, underwent scaling and the depigmentation procedure was done after the patient was clinically plaque and gingivitis free. Gingival depigmentation was carried out from second premolar to second premolar. For left quadrant bur abrasion and. scraping techniques were used and for right quadrant electrocautery was used. [Figure - 2]. The bur abrasion technique involves deepithelization of heavily pigmented gingival areas using high speed rotary instruments after adequate local anesthesia. A large round bur and straight bur with copious saline irrigation was used. Pressure was minimal with feather light brushing strokes and. without holding bur in one place. Any bur can be used for the purpose, taking enough care not to cause pitting of the gingival surface or to remove too much of tissue. Care was taken to remove all the remnants of melanin pigment as thoroughly as possible and a scraping procedure using the scalpel blade was used for the purpose. However, some areas were left due to presence of very thin gingiva to avoid exposure of bone in region of attached gingiva.

The marginal gingiva was also very thin and thus some remnants were left in order to prevent gingival recession.

Electrocautery was used for depigmentation of the upper right anterior gingiva till second pre-molar. A loop electrode was used for deepithelizing the gingiva. It was used in a light brushing strokes and the tip was kept in motion all the time. Keeping the tip in one place could lead to excessive heat build up and destruction of the tissues. Finally a perio-pack was placed over the wound area and oral hygiene instructions were given. Pack was removed after one week and the area debrided. Three month post­op examination showed well epithelialized gingiva, which was pink and pleasant but with few sites showing remnants of pigmentation [Figure - 3]. Future follow-up has to reveal whether these remnants will lead to faster recurrence ofpigmentation.

   CASE 2 and 3 Top

A 24 year old male patient [Figure - 4] and a 23 year old female [Figure 5 and 6] patient visited the department complaining of the same problem. After scaling, an epithelial excision or partial/split thickness flap was planned. The pigmented gingival epithelium from left first pre-molar to first pre­molar of the opposite side was excised using no 15 BP blade [Figure 7, 8, 9, 10]. Care was taken to include the epithelium at the tip of interdental papilla and at the muco gingival junction on the other end. Care was also taken to remove any remnants of the pigmented areas that were left out. A periodontal pack was placed and oral hygiene instructions given. Pack was removed after 1 week and examination at 3 months revealed fully epithelialized pink gingival [Figure 11,12].

   Discussion Top

Pigmented gingival tissue, many at times forces the patients to seek cosmetic treatment. Several treatment modalities have been suggested and presented in the literature ranging from a simple slicing method to free gingival grafts or "push back" operation where alveolar bone may be exposed leading to bone loss, secondary healing, discomfort and pain. However, many easy, simple and effective techniques are described, which gives desired results. But pigment recurrence has been documented to occur, following the surgical procedure, within 24 days to 8 years long period. The epithelium­melanin unit is formed by the melanocytes and keratinocvtes. There is little information on the behavior of melanocytes after surgical injury. A study by Oswaldo et al , 1993 showed that gingival surgical procedures performed solely for cosmetic reasons, offer no permanent results. Spontaneous repigmentation has been shown to occur and the mechanism suggested is that the melanocytes from the normal skin proliferate and migrate into the depigmented areas. Further research is required on repigmentation to study the factors affecting rate and length of time required for recurrence of pigmentation. Research should also focus on finding a solution for preventing the recurrence and till then repeated depigmentation should be done to eliminate the unsightly pigmented gingiva.

In the present case series 3 cases, were treated using electrosurgery, a combination of bur abrasion-scraping and epithelial excision techniques (conventional slicing). Following surgical procedure, patients were recalled at 1 month, 2 and 3 months, to evaluate recurrence of pigments. Electrosurgery showed good results, followed by epithelial excision and bur abrasion-scraping techniques. The sites operated with bur abrasion-scraping method showed a slight recurrence of pigments than the other two methods. The pattern observed was patchy in distribution and had occurred by 3 months.

Another feature of this case series was that the depigmentation was carried out in dark skinned individuals, whose chief complaint was the unsightly gingival pigmentation. The patients had high smile lines pronouncing the effects of deeply pigmented gingiva. The patients were explained about the possibility of recurrence and about the excessive contrast between the skin and gingival color after the procedure. Although few reports consider the depigmentation procedure in dark skinned individuals as a contraindication, for the reasons of faster recurrence of pigmentation and due to the fact that there might be excessive color contrast between the skin and gingiva after the procedure, the procedure was taken up considering the patients' esthetic concern. This produced successful results with good patient satisfaction, which created a pleasant and confident smile.

The superior efficiency of electrosurgery over epithelial excision or bur abrasion-scraping techniques, seen in the present case series, could be explained based on Oringers, 1975 [11] "Exploding cell theory". According to the theory it is predicted that the electrical energy leads to molecular disintegration of melanin cells, present in basal and suprabasal cell layers of operated and surrounding sites. Thus, electrosurgery has a strong influence in retarding migration of melanin cells from the locally situated cells, which were detected clinically to be removed [11].

Few other techniques reported in the literature are laser tissue ablation, cryotherapy, free gingival graft, alveolar bone denudation techniques.

Cryotherapy is a method of tissue destruction by rapid freezing. The cytoplasm of the cells freeze leading to denaturation of proteins and cell death. This procedure does not require the use of local anesthesia, is relatively a painless procedure and has shown to produce excellent results lasting for several years (Tal et al , 1987). This procedure does not require even a periodontal dressing. However, the removal of pigments carrot be evaluated during the procedure and requires a separate sitting after about 5 days, during which the residual pigmentation should be removed. Thus the depigmentation procedure requires a minimum of two sittings. One case was treated using liquid nitrogen (-190°C using dip-stick method [Figure - 13]. This method utilizes a small cotton bud / swab dipped in liquid nitrogen, which is applied to the pigmented area and maintained in contact for around 20­30 sees as described by Tal et al , 1987. But it was noticed that the swab was too small to hold enough quantity of liquid nitrogen to be applied to the area of interest, as it evaporated very fast. So larger cotton, rolled around a tweezer was used, which was still not enough to maintain a contact time of 20-30 sees. Thus the procedure required multiple applications oftheliquid.

Another problem faced was that there were no immediate clinical changes noticed which made it difficult to analyze the site of previous application [Figure - 14]. The patient was recalled after 5 days for evaluation of depigmentation, but had missed the appointment and the 7th day evaluation revealed a patchy depigmentation [Figure - 15]. The procedure had to be repeated in the areas of existing pigmentation. Some of the problems encountered while using cryotherapyprocedure were -

  • The cryotherapy procedure requires a special container for storage of liquid nitrogen which is not commonly available [Figure - 16].
  • Dispensing of liquid nitrogen. As it is highly volatile, it is very difficult to maintain 20-30 seconds of freezing at each site. The amount required for treating a small pigmented area is quite high. Each time the container of liquid nitrogen is opened, quite a lot of liquid is evaporated.
  • The depth of penetration is difficult to control and prolonged freezing could cause excessive tissue destruction.
  • The shelf life of liquid nitrogen is not adequate for storage for long periods due to its faster rate of evaporation even in closed containers.
  • The liquid nitrogen has to be handled carefully as the accidental contact can cause injury to the skin or other contact areas.

With all these limitations of cryotherapy, it is better to use alternative procedures that are easier, better, simpler and cost effective.

Thus the present case series has showed us that methods are available for depigmentation, which can be made use of, instead of cryotherapy. The available literature does not mention anything about dispensing, shelf life or give proper directions for the usage of liquid nitrogen.

An alternative to dip-stick method is the use of cryosurgical guns with special probes, but requires extensive sophisticated equipment not available commonly. This involves a gas-expansion cryosurgical system which works based on Joule-Thompson effect.

Another effective treatment for depigmentation is using lasers. A one step laser treatment is available usually sufficient to eliminate the pigmented areas and do not require any periodontal dressing. This has the advantages of easy handling, short treatment time, hemostasis and decontamination and sterilization effects. But this approach needs expensive and sophisticated equipment that is not available commonly at all places and makes the treatment very expensive.

Free gingival grafting (Mahmoud Tamizi, 1996) is quite an invasive and extensive procedure and has not been advised for depigmentation procedures routinely. It also has the disadvantage of a second surgical site, additional discomfort and poor tissue color matching at the recipient site.

Bone denudation procedure is again an invasive method not used for the obvious reasons of bone loss and the discomfort involved in the procedure for the patient. Gingival depigmentation has been attempted by displacing the flap (push back technique), by Kon et al and have reported that melanocytes may lose their ability transiently to produce and transfer the pigment to the keratinocytes, but return to normal much faster than do melanocytes observed after gingivectomy or other procedures [6].

There are several simple, easy, non-invasive techniques which have produced excellent results at reduced cost for the patient. In the present case series all the three methods used were easy, simple, available at all places and cost effective. The patients are being followed-up regularly to check for the pattern, rate and duration of recurrence of the pigmentation and the male patient (case 2) showed recurrence of pigmentation by 7 months. He was satisfied with the result as he was informed earlier about the chances of recurrence and was ready to undergo depigmentation again.

   Conclusion Top

The growing esthetic concern requires the removal of unsightly pigmented gingival areas to create a pleasant and confident smile, which altogether may alter the personality of an individual. This could be easily attained by using any of the above three methods used in this case series or the other methods described in the literature. The methods used here produced desired results and above all, the patients were satisfied with the outcome, which is the ultimate goal of any therapy that is carried out.

   Acknowledgements Top

I would like to thank Dr. Harsha, my colleague for his valuable help in taking the photographs with great care. I would also like to thank Dr.Suresh Babu and Dr. Vijay Kumar for providing liquid nitrogen with the special storage container without which this study would not have beenpossible.

   References Top

1.Liebart ME, Deruelle CF, Santini A, Dillier FL, Corti VM, et al . Smile Line and Periodontium Visibility. Perio,1:17-25, 2004.  Back to cited text no. 1    
2.Granstien RD,Sober AT. Drug and Heavy Metal Induced Hyperpigmentation. J.Am.Acad. Dennatol, 5:1-6,1981.  Back to cited text no. 2    
3.Dummet CO oral pigmentation. In:Dummet CO,editor. First symposium on oral pigmentation. JPeriodonto1,31:356-60,1960.   Back to cited text no. 3    
4.Page LR, Coro RE, Crawford BE, Giansanti JS, Weathers DR. The oral melanotic macule. Oral Sung Oral Med Oral Pathol, 44:219-26,1977.   Back to cited text no. 4    
5.Trelles MA, Verkruysse W, Segui JM, UdaetaA. Treatment of melanotic spots in the gingiva by argon laser. J Oral Maxillofac Sung, 51:759-61, 1993.  Back to cited text no. 5    
6.Kon S, Bergamaschi 0. Dome Al. Ruben MP. Melanin Repigmentation after Gingivectomy: A 5-Year Clinical and Transmission Electron Microscopic Study in Humans. Int J. Periodont RestDent,13:85-92,1993.  Back to cited text no. 6    
7.Dummett CO, Bolden TE. Postsurgical clinical Repigmentation of the gingiva. Oral Surg Oral Med Oral Pathol,16:353-365,1963.  Back to cited text no. 7    
8.Perlmutter S, Tal H. Repigmentation of the gingivafollowing surgical injury. JPeriodontol, 57:48-50,1986.  Back to cited text no. 8    
9.Ishikawa I, Aoki A, Takasaki AA. Potential application of Erbium:YAG laser in periodontics. J PeriodontRes, 39:275-285, 2004.   Back to cited text no. 9    
10.Tal H, Landsburg J, Kozlovsky A. Cryosurgical depigmentation of the gingiva. J Clin Periodonto114:614-617,1987.  Back to cited text no. 10    
11.Oringer MJ. Electrosurgery in Dentistry, 2nd edu, Philadelphia. W.B. Saunders Co, 1975.   Back to cited text no. 11    

Correspondence Address:
S Sunil
Department of Periodontics, J.S.S. Dental College & Hospital, S.S Nagar, Bannimantap, Mysore 570015, Karnataka
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0970-9290.29901

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[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4], [Figure - 5], [Figure - 6], [Figure - 7], [Figure - 8], [Figure - 9], [Figure - 10], [Figure - 11], [Figure - 12], [Figure - 13], [Figure - 14], [Figure - 15], [Figure - 16]

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