The oral health of children represents a critical concern that warrants significant attention from parents (Tadakamadla & Tartaglia, 2021). Failure to diagnose and address oral diseases in a timely manner can lead to severe complications (Tadakamadla & Tartaglia, 2021). According to data from the World Health Organization, despite the focus on oral health, a considerable segment of the global population, particularly children, experiences dental and gum diseases. This issue is particularly prevalent among disadvantaged groups within society (Nam & Oh, 2024). Children are particularly susceptible to dental caries and other forms of dental damage. The adverse effects of oral health issues extend beyond the immediate health of teeth and gums; they can also substantially elevate the risk of systemic conditions such as cardiovascular disease, cancer, and diabetes (Alwadi et al., 2024). Although the precise incidence of oral mucosal lesions in children across various age groups remains undetermined, these lesions are commonly observed (Alwadi et al., 2024). The characteristics of these lesions enable healthcare professionals to exclude traumatic or neoplastic etiologies and to consider infectious origins. In such instances, the lesions may serve as precursors or indicators of systemic diseases or may signify localized infections (Palatna & Shpak, 2024).

Stomatitis, also referred to as oral mucositis, is characterized by inflammation of the mucosal tissue within the oral cavity or on the lips (Stoopler et al., 2024). The predominant forms of this condition include herpes labialis, commonly known as cold sores, and aphthous ulcers, commonly referred to as canker sores (Stoopler et al., 2024). Canker sores are small, superficial lesions that manifest within the oral cavity or on the gingiva (Montgomery-Cranny et al., 2015). Typically characterized by a white or yellow appearance encircled by a red halo, these ulcers are associated with significant discomfort, particularly during activities such as eating, drinking, or speaking and affects approximately 20 % of the general population, with an estimated prevalence of 9 % among children (Montgomery-Cranny et al., 2015). The etiology of canker sores in children is multifactorial, encompassing viral, parasitic, and bacterial infections, as well as mechanical trauma to the oral mucosa. The involvement of parasitic organisms in the pathophysiology of canker sores remains a subject of ongoing debate, with limited understanding of the specific conditions that facilitate their proliferation (Andriakopoulou et al., 2024).

The primary parasites identified in the human oral cavity are Entamoeba gingivalis (Eg) and Trichomonas tenax (Tt) (Eslahi et al., 2021). These parasites may be transmitted via saliva, contaminated food containers, drinking water, and various other routes (Eslahi et al., 2021). They predominantly reside in the upper sections of the digestive system, which encompasses the mouth, teeth, gingival margins, and interstitial spaces between teeth, in addition to the respiratory tract (Eslahi et al., 2021, Stoyanov et al., 2024). Historically regarded as non-pathogenic microorganisms by numerous dental professionals, recent research has established associations between these parasites and various oral health conditions, including periodontal disease, gingivitis, and osteomyelitis (Arpağ & Kaya, 2020). Consequently, future investigations may explore the influence of these parasitic agents on the development of stomatitis and the subsequent therapeutic approaches. In recent years, a substantial body of research has focused on the prevalence of oral cavity parasites among diverse populations, including pediatric cancer patients (Kooshki et al., 2023), children with intellectual disabilities (Kooshki et al., 2024, Selahbarzin et al., 2024), individuals undergoing hemodialysis (Azadbakht et al., 2023), pregnant women (Azadbakht et al., 2022), and patients suffering from periodontitis (Derikvand et al., 2018) and gingivitis (Mahmoudvand et al., 2018). However, there remains a critical need to investigate the frequency of these parasites and the associated risk factors specifically within individuals diagnosed with gingivitis. Given the significance of oral and dental hygiene, especially among individuals with stomatitis, this study for the first time seeks to assess the prevalence, socio-economic characteristics, and risk factors associated with oral cavity parasites in children with stomatitis in Iran.