Mucosal deposit after triamcinolone injection: a case report

Abstract

Background

Oral ulcers exhibit diverse symptoms and etiologies. The treatment approach varies depending on the size and characteristics of the ulcer, typically starting with topical therapies such as steroid or antifungal mouth rinses. While most ulcers respond well to these localized treatments, some cases necessitate systemic interventions, including oral medications or intralesional injections.

Case presentation

A 59-year-old man with a one-month history of a persistent oral ulcer in the maxillary vestibule was diagnosed with major aphthous ulcer and treated with intralesional triamcinolone injection and corticosteroid gargle. The ulcer healed completely within two weeks, but a triamcinolone deposit remained asymptomatic and resolved spontaneously within a month. The patient experienced no discomfort and required no further intervention.

Conclusions

While triamcinolone is a highly effective and rapid treatment for oral mucosal ulcers, caution is advised when treating ulcers above the alveolar bone. It is preferred to administer injections in the corresponding vestibular groove near the buccal mucosa, which has a rich blood supply, rather than above the alveolar bone. Otherwise, reducing the dosage or switching to a more easily absorbable corticosteroid, such as dexamethasone, may be carefully recommended.

Background

The oral cavity possesses a unique histological structure and environment distinct from other tissues in the body. It can be considered both a mirror and a warning signal for systemic health, as it is one of the most well-protected areas by the immune system, yet often the first to manifest symptoms when systemic immunity is compromised [1]. The oral cavity is susceptible to a wide range of infections, including viral, fungal, and bacterial infections, leading to diverse lesions such as ulcerative and vesicular manifestations. Additionally, ulcers and benign soft tissue lesions caused by various stimuli are frequently observed. However, many oral mucosal diseases are rooted in autoimmune mechanisms, with their precise etiology and pathogenesis remaining unclear. Consequently, treatment strategies primarily focus on management rather than complete resolution or cure.

Ulcerative lesions in the oral cavity can result from various causes, including herpes simplex virus infection, recurrent aphthous stomatitis, oral lichen planus, and trauma [2]. Among these, traumatic stomatitis arises from physical, mechanical, thermal, or chemical irritations of the mucosa. Common contributing factors include malocclusion, ill-fitting prostheses, oral habits, burns, and medications. Treatment primarily involves the elimination of causative factors and the use of localized therapies such as steroid mouth rinses or ointments. If these approaches prove ineffective, systemic steroid administration or intralesional steroid injections may be considered [3].

Triamcinolone acetonide is a synthetic corticosteroid medication with approximately eight times the potency of prednisone [4]. It has been widely used for the treatment of oral ulcers, both as a topical agent and through intralesional injections to manage inflammatory oral lesions [3]. Intralesional steroid therapy has demonstrated efficacy in managing various oral conditions, including oral lichen planus (OLP) [5, 6], recurrent aphthous stomatitis [7, 8], oral chronic graft-versus-host disease [9], pemphigus vulgaris [10], mucous membrane pemphigoid [11], and traumatic ulcers.

However, due to its pharmacological properties, triamcinolone may occasionally remain unabsorbed and persist at the injection site for an extended period [12]. This retention phenomenon is rarely reported in oral mucosa, but there has been one case where it occurred above the alveolar bone [13]. In this study, we report a case of mucosal deposit following intralesional triamcinolone injection, examining its clinical and pathological features. This study received approval from the Institutional Review Board of Kyungpook National University Dental Hospital (IRB No. KNUDH-2024-11-02-00).

Case presentation

A 59-year-old man presented to the Department of Oral Medicine at Kyungpook National University Dental Hospital with an oral ulcer located in the right upper vestibule. The patient reported that the ulcer had started one month prior and had progressively increased in size. No treatment had been administered before his visit. The patient had a history of taking medication for hypertension but reported no other systemic diseases or allergies.

Panoramic and periapical radiographs revealed no significant findings in the teeth or periodontal tissues. A well-demarcated 2 cm ulcer was observed at the buccal mucogingival junction of teeth #12–14 (Fig. 1-a). The patient could not remember any mechanical irritation to the affected area. No abnormalities were noted in other areas of the oral cavity or extraoral regions.

The patient was clinically diagnosed with major aphthous ulcer, and the treatment plan was explained. Although a differential diagnosis to rule out malignancy was necessary due to the lesion’s persistence for one month, a non-invasive yet effective therapeutic intervention was prioritized, given that the patient had not received any prior treatment. Considering the location of the ulcer in the maxilla, its persistence for over a month, and its size of 2 cm, corticosteroid gargle alone may not be effective. Therefore, a combination of corticosteroid gargle and intralesional injection was deemed necessary. If the lesion failed to resolve following injection therapy, an incisional biopsy was planned for prompt execution. At the initial visit, intralesional injection therapy was performed using triamcinolone. The triamcinolone used in this study was the liquid injectable formulation (Triam^®, Shinpoong pharm Co., Seoul, Korea), with each vial containing 40 mg of triamcinolone in 1 mL of solution. Using an insulin syringe, 0.2 mL of the solution, equivalent to 8 mg of triamcinolone, was administered into the lesion. Additionally, the patient was prescribed a corticosteroid gargle (0.1% prednisolone solution) to be used for 5 min, three times daily for one week. After one week, the ulcer had almost completely resolved, but triamcinolone deposit was observed at the superior aspect of the ulcer site (Fig. 1-b). The patient did not notice or feel discomfort related to the retention. He was instructed to continue using the corticosteroid gargle for an additional week. Two weeks later, the ulcer had healed completely without any visible traces, but the triamcinolone deposit remained unchanged (Fig. 1-c). As the patient experienced no pain or discomfort, he did not return for further follow-up. A telephone follow-up one month later confirmed that the triamcinolone deposit had resolved spontaneously.

Fig. 1

Ulcer at the buccal mucogingival junction of teeth #12–14. a. Before. b. After 1 week. c. After 2 weeks

Discussion

The therapeutic efficacy of corticosteroids, initially described approximately half a century ago, is now recognized to stem from their anti-inflammatory and immunosuppressive properties [14]. The anti-inflammatory effects of glucocorticoids involve multiple mechanisms, including activation of glucocorticoid receptors, regulation of glucocorticoid-responsive genes, and the release of anti-inflammatory mediators such as lipocortin-1, interleukins and inhibition of nuclear factor-κB activity by macrophages and eosinophils [15]. The immunosuppressive effects of corticosteroids primarily result from the suppression of antigen-driven T-cell proliferation, mediated through the inhibition of interleukin-1 release from monocytes [16].

Triamcinolone acetonide is a highly effective topical corticosteroid that has been extensively used for the treatment of oral mucosal diseases [4]. This therapy provides a high concentration of corticosteroid directly at the ulcerative site with minimal systemic dispersion or absorption [17], thereby promoting healing with fewer adverse effects compared to systemic steroid therapy [18]. The therapeutic outcomes of intralesional injection and mouth rinse therapies were reported to be similar; however, the rate of adverse effects was significantly lower with intralesional injection than with mouth rinses [19].

In the context of local drug application, adjuvant perilesional or intralesional triamcinolone acetonide injections have been reported to alleviate or resolve the signs and symptoms of oral pemphigus vulgaris. Perilesional or intralesional triamcinolone acetonide appears to be an effective clinical adjunct to conventional immunosuppressive therapy, offering benefits such as shortening the time to complete clinical remission, reducing the total corticosteroid dose required, and improving patient compliance [10].

Intralesional injection of triamcinolone acetonide is also commonly used for the treatment of erosive OLP and has shown some efficacy. However, triamcinolone acetonide is a moderately potent glucocorticoid with a relatively short duration of action. In contrast, betamethasone, with a longer half-life of 36 to 54 h, may provide an alternative for intralesional therapy in the management of erosive oral lichen planus [6].

Triamcinolone deposition after injection could occur because triamcinolone is a suspension-type formulation rather than a fully soluble solution, which is likely absorbed more slowly [12]. However, there is no clear histopathological study on the cause of this phenomenon. Several cases have been reported in various organs, including the retina following treatment for diabetic macular edema [20] and as a subconjunctival deposit following bleb-forming filtration surgery [21]. Similar deposit phenomena have also been observed in the skin [22]. However, triamcinolone deposition in the oral mucosa is rarely reported.

In this case, 0.2 ml of TA (40 mg/ml) was injected into the normal subepithelial connective tissue surrounding the lesion, at a depth of 3–5 mm, in a single puncture. The experienced practitioner administered the injection within the commonly accepted range for intralesional injections, where 0.5 to 0.7 ml is typically injected in a single dose for oral mucosa [17, 19, 23]. Therefore, it is suggested that the injection technique or dosage is not a major contributing factor to the occurrence of deposition. Since the lesion resolved with a single injection in this case, it is difficult to determine whether the deposition was a result of the patient’s tissue response. However, there have been no reports of recurrent deposition occurring as an adverse effect of intralesional triamcinolone injection for specific patients.

It is hypothesized that the local characteristics of the injection site may play a significant role, as suggested in a previous case report. Interestingly, this phenomenon does not occur in other oral mucosal areas, such as the tongue, buccal mucosa, or soft palate, but appears to be specific to ulcers located above the alveolar bone. The previous case report describes a white spot observed near the attached gingiva because of an intralesional injection [13]. The authors explained that the marginal area of the attached gingiva is not a suitable injection site due to its lack of submucosal layer and the reduced number of blood vessels in the lamina propria. Although the exact mechanism remains unclear, it is hypothesized that triamcinolone absorption may be inhibited by the underlying alveolar bone.

Two aspects warrant further consideration regarding the formation of corticosteroid deposits. First, if the differences in drug absorption rates are due to tissue-specific characteristics such as reduced blood flow, it would be beneficial to compare absorption rates in tissues with higher vascularity. Such a study could help identify the optimal injection site, thereby minimizing the occurrence of deposits. Second, if the formation of deposits is primarily influenced by the thickness of the mucosal tissue, where the drug’s presence is visually detectable depending on tissue thickness, it is important to avoid injecting too superficially, even when targeting the buccal or lingual mucosa. Superficial injection could lead to the drug becoming more visibly apparent on the mucosal surface, which underscores the need for careful attention to injection depth, regardless of the anatomical site.

Conclusions

Triamcinolone is widely used for the treatment of various oral ulcers due to its established safety profile. However, its pharmacological properties occasionally result in prolonged retention at the injection site. While triamcinolone is a highly effective and rapid treatment for oral mucosal ulcers, caution is advised when treating ulcers above the alveolar bone. It is preferred to administer injections in the corresponding vestibular groove near the buccal mucosa, which has a rich blood supply, rather than above the alveolar bone. Otherwise, reducing the dosage or switching to a more easily absorbable corticosteroid, such as dexamethasone, may be carefully recommended.