Oral Ulceration Associated with Clear Aligners: A Narrative Review of Etiology, Prevention, and Management

Abstract

Over the past two decades, clear aligner therapy (CAT) has become a widely accepted alternative to fixed orthodontic appliances due to its removable nature and improved esthetics. Despite these benefits, several oral complications such as mucosal irritation and ulcer formation have been observed, which may negatively influence patient comfort and adherence to treatment. This review aims to summarize the current evidence on the occurrence, contributing factors, and management of oral ulcers linked to clear aligner therapy. A narrative literature search was performed in PubMed/PMC, Scopus, and Google Scholar up to September 2025. Search terms included “clear aligner,” “Invisalign,” “oral ulcer,” “mucosal ulceration,” “oral lesions,” and “adverse effects.” Eligible sources included clinical studies, case reports, and review papers. Oral ulcerations during CAT appear to be multifactorial. Reported causes include mechanical trauma from aligner edges or attachments, chemical irritation from residual materials or cleaning agents, microbial changes that promote plaque buildup, and patient-related conditions such as mucosal sensitivity or recurrent aphthous stomatitis. From this study we concluded that ulcers associated with clear aligners can significantly affect patient compliance. Preventive measures include careful aligner design, clear oral hygiene instructions, and early identification of soft tissue irritation. When ulcers develop, management strategies may involve minor adjustments to the aligner, topical medication, and supportive care. Further studies are recommended to establish standardized preventive and therapeutic protocols.