Comparative Study of the Use of Trichloroacetic Acid and Phenolic Acid in the Treatment of Atrophic-Type Acne Scars

BACKGROUND: Many therapies involving varying degrees of complexity have been used to treat acne scars, but none is considered the gold standard treatment. OBJECTIVE: A comparative evaluation of 88% phenol and 90% trichloroacetic acid (TCA) applied using the chemical reconstruction of skin scars (CROSS) technique. MATERIALS AND METHODS: A nonrandomized, single-blinded self-controlled clinical trial was conducted among patients with ice pick-type and boxcar-type atrophic acne scars. Using 88% phenol on the left hemiface and 90% TCA on the right hemiface was adopted as the standard practice of the CROSS technique. The dermatological quality of life index (DLQI) questionnaire, acne scar grading scale Échelle d´Evaluation Clinique des Cicatrices d'Acne (ECCA), and evaluation of improvement were performed pretreatment and post-treatment. RESULTS: Regarding ECCA, significant differences were found in pretreatment and post-treatment (p < .001). Regarding tolerance to pain, it was found that the discomfort felt with 90% TCA was significantly less than that felt with 88% phenol (p = .020). Regarding the quality of life measured with the DLQI, the results showed that the mean score in post-treatment assessment was significantly lower than that in the pretreatment assessment (p < .05). Hypochromia and enlargement scar were only seen after the use of 90% TCA. CONCLUSION: This study confirmed the efficacy of both TCA and phenol for treating such scars, with less severe complications from the use of phenol.