Removal of Refractory Erosive-atrophic Lichen Planus by the CO2 Laser-Medical Fibers

Keywords:medical fibers, laser fiber,  Time:18-02-2016
The prevalence of Lichen Planus has been reported to be from 1 to 2% in different populations [1,2] and it is more frequently observed in females [3,4]. Oral Lichen Planus (OLP) usually occurs bilaterally in the buccal mucosa, the lateral border of the tongue and the gingiva in keratotic (reticular, popular, plaque-like) and nonkeratotic (erosive, atrophic and bullous) forms [4]. The nonkeratotic forms of OLP are usually associated with severe pain/ discomfort and intolerance of the patient to consume hot or spicy food. Furthermore, the risk of malignant transformation in erosive lesions may be higher than other types of OLP [3,5], because the deeper epithelial layers are exposed to oral carcinogens [6]. Therefore, these lesions should be treated and monitored in the long term. Despite the great attempts to develop efficient modalities for managing OLP lesions, no definitive treatment is now available and the current approaches mainly focus on relieving the signs and symptoms of the disease rather than to be curative. Topical corticosteroids are considered as the mainstay in the treatment of OLP, but they can produce adverse effects including thinning of the oral mucosa, secondary candidiasis and possibly tachyphylaxis and adrenal suppression [7,8]. Furthermore, the long period of pharmacologic therapy and the necessity for repeated applications are unpleasant for most patients. Several potent immunosuppressive and immunomodulating agents have been proposed as alternatives to corticosteroids for the treatment of painful symptoms of OLP affected patients [7], but complete and persistent improvement has not been achieved by any of them and all may cause adverse effects. Non-pharmacological approaches have also been tried for OLP treatment such as photodynamic therapy, and low-level or high-power laser treatment [7]. Laser surgery is an effective method for elimination of signs and symptoms of OLP. The CO2 laser is well suited for ablation of superficial soft issue lesions of oral mucosa including leukoplakia and lichen planus because of its strong absorbance in water. The advantages of CO2 laser fiber surgery are the sealing of blood and lymphatic vessels, sterilization of the surgical wound, no need for sutures, and healing of the excised tissue with minimal scar [9,11]. This laser also helps to eliminate or reduce pain and burning sensation associated with the lesions because of its effects on the nerve supplies [9].

This study aimed to investigate the effectiveness of CO2 laser evaporation for the treatment of patients presenting drugresistant, erosive-atrophic OLP.

Materials and Methods

Ten patients with erosive-atrophic OLP were selected from those attending the Department of Oral Medicine, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran. The inclusion criteria limited patients to those that had been treated with medications including topical corticosteroids for at least 1 month beforehand, but the lesions were not eliminated completely or recurred.

The diagnosis of lichen planus was made clinically according to the definition of World Health Organization (WHO), and then was confirmed by histopathologic examination where vacuolar alteration of the basal layer of the epithelium and a band like infiltrate of lymphocytes in the lamina propria were evident [12,13]. The patients who had signs of dysplasia, in-situ carcinoma or any other malignancy, as well as those with lichenoid reactions and those who received topical or systemic medicine for OLP within the last one month were excluded from the study. The research protocol was approved by the Ethics Committee of Mashhad University of Medical Sciences.

The patients were explained about the treatment procedure and an informed consent was obtained from each participant before the commencement of the study. The patients were asked about the demographics and medical history by an oral medicine specialist (S.B) and the site, type (erosive or atrophic) and size of the lesions was recorded. The degree of pain/discomfort was also evaluated before laser treatment (T0). A CO2 laser device (Daeshin, model DS-40U, Daeshin Enterprise Corp, Guro-gu, Seoul, Korea) was used for evaporation of OLP lesions under local anesthesia. The laser operated at continuous-wave mode with power of 5 W. The lesion was vaporized with a slightly defocused beam using sweeping movement until the subepithelial tissue was reached. A safety margin of about 2 mm was taken around the lesion. The patient and the clinician wore protective glasses during the surgery. A Persica mouthwash (containing an extract of Salvadora persica) and a Non-Steroidal Anti-Inflammatory Drug (NSAID) were prescribed for postoperative care. The patients were followed up at 1 month (T1) and 3 months (T2) after laser surgery. In each follow-up, the lesion size and type as well as the degree of pain and discomfort were recorded similar to the pretreatment evaluation, and digital photographs were taken. The lesion size was defined as the longest distance in mm from the end to the end of the atrophic and erosive areas of the OLP lesion.

A caliper was used for measuring lesion size. The severity of pain and discomfort was determined using a Visual Analogue Scale (VAS) and the patient was requested to mark the degree of pain experienced on a 10-cm scale with 0 indicating no pain and 10 indicating the worst possible pain. The pain data were then scored according to the classification described in Box 1 [6]. In addition to measuring lesion size and pain level, the Thongprasom sign scoring [14] was used to represent the clinical data (sign) before the laser treatment and at follow-up periods as indicated in Box 2. Efficacy Index (EI) [6] was calculated using the following formula: [(total score of the lesion before treatment-total score of the lesion after treatment)/total score of the lesion before treatment]×100 The EI was categorized into a 5-rank scale as demonstrated in Box 3.