In Korea, a rare disease is defined as a medical condition characterized by a prevalence of fewer than 20,000 individuals or an indeterminate prevalence due to challenges associated with diagnosis, as established by the protocols and criteria outlined by the Ministry of Health and Welfare [1].

According to statistical data provided by the Korea Disease Control and Prevention Agency, as of January 1, 2022, 1,123 rare diseases have been formally documented, with 54,952 cases of rare diseases reported in Korea in 2022. Among high-frequency diseases (defined as those affecting more than 200 individuals), the classification of patients by age revealed that 1.0% were under 1 year of age, 1.8% were between 1 and 9 years, and 5.4% were between 10 and 19 years of age. By 2022, it was estimated that approximately 8.2% of patients with rare diseases were pediatric. Representative pediatric rare diseases include Crohn’s disease, Moyamoya disease, systemic lupus erythematosus, tetralogy of Fallot, epilepsy, juvenile rheumatoid arthritis, spina bifida, microtia, and neurofibromatosis [2]. As of February 2025, 1,314 rare diseases have been officially recognized by the Korea Disease Control and Prevention Agency [3].

Approximately 15% of patients with rare diseases experience orofacial complications [4]. Abnormal growth of the craniofacial region often leads to orofacial anomalies, such as dysgnathia and clefts [5], with a high incidence of malocclusion, including anterior open bite and high palate [6-8]. In addition, genetic defects may lead to dental developmental abnormalities such as tooth agenesis [9-11], microdontia [12,13], and enamel hypoplasia [6], and may also be associated with xerostomia [6]. In patients with rare diseases, not only complications but also conditions that hinder oral hygiene can lead to dental issues [14,15]. Patients with intellectual disabilities, executive function disorders, or learning disabilities often struggle to maintain oral hygiene [16,17], thereby increasing the risk of dental caries and gingival-periodontal disease [18-21]. Furthermore, maladaptive oral habits such as bruxism, mouth breathing, and tongue thrusting have been reported [6].

Poor oral health in patients with rare diseases can hinder proper nutrition, induce pain, and disrupt sleep, speech, and daily activities, ultimately decreasing their quality of life and significantly impacting their overall health [19,22-24]. Therefore, there is a need to focus on dental care to improve the overall health and quality of life of patients with rare diseases. Given that many rare diseases manifest during childhood [25], preventive approaches and early interventions in dental care are essential for pediatric patients with rare diseases [26], highlighting the important role of pediatric dentists.

Despite this importance, dental care for patients with rare diseases remains challenging due to several factors: (i) Managing oral hygiene is difficult due to the heavy daily routines of patients with rare diseases and a lack of awareness and information regarding oral care among caregivers [14,26]. (ii) Presently, 16 regional oral health centers for individuals with disabilities operate in Korea, and some university dental hospitals have specialized clinics for dental care of individuals with disabilities [27]. However, there are no officially designated dental care facilities specifically for patients with rare diseases. Although 17 regional specialized institutions for the management of rare diseases operate in Korea, none of these institutions have a dental department within their rare disease centers [28]. Consequently, patients with rare diseases who also have disabilities receive dental care at regional oral health centers for individuals with disabilities or specialized clinics in university dental hospitals, while those without disabilities receive dental care at general dental facilities. (iii) The unique characteristics of rare diseases make specialized dental interventions challenging in primary care institutions, which often lack the requisite expertise in behavioral management and understanding of systemic conditions [26,29,30]. (iv) Limited cognitive and motor development in patients with rare diseases poses challenges in accessing advanced dental institutions [31]. (v) In Korea, policies are in place to provide financial support for certain reimbursable medical expenses for patients with rare diseases registered as beneficiaries under the special case program [32]. However, most non-reimbursable dental treatments are excluded from this coverage. Furthermore, some dental procedures are covered for patients with rare diseases who are also diagnosed with brain lesions, intellectual disabilities, mental disorders, or autism spectrum disorders [33,34]. However, these covered procedures are confined to specific items, such as fluoride application and general anesthesia during dental treatment, and are only applicable to those with an associated disability diagnosis. Consequently, the financial support for dental care specifically tailored to patients with rare diseases remains inadequate.

Therefore, developing appropriate policies and management guidelines to facilitate dental care in patients with rare diseases is imperative. To achieve this, an evaluation of the current dental care status for these patients, as well as their satisfaction and needs concerning dental care, is essential. One study examined the dental treatment patterns of pediatric patients with rare diseases at a single institution in Korea and highlighted the significance of personalized dental care for these individuals [35]. Nevertheless, to date, no nationwide multicenter cohort study has been conducted on the dental care utilization of pediatric patients with rare diseases in Korea, nor has any research focused on caregivers’ perceptions, satisfaction, and needs regarding the dental care of these children.

Therefore, the purpose of this study was to investigate dental care utilization and satisfaction with dental treatment among patients with rare diseases who visited a dental hospital and to provide data for future policy recommendations.

This study was performed to assess the current status of dental care utilization among pediatric patients with rare diseases through a survey of their caregivers. Additionally, it investigated caregivers’ perceptions regarding the dental care and oral health of their children alongside their satisfaction with dental treatment. The goal was to provide reference data for developing improved support systems and facilities related to the dental treatment of pediatric patients with rare diseases. The findings present a nationwide overview of dental care utilization among children with rare diseases in Korea and emphasize the requests of caregivers for enhancements in the dental care system. A summary of the main findings is illustrated in Fig. 5.

In this study, rare diseases were classified into three categories: (i) congenital disorders, which are likely to be accompanied by structural anomalies in the oral and maxillofacial region [7,9,11-13,20]; (ii) neurological diseases, which may involve cognitive and motor limitations, complicating oral hygiene management [20]; and (iii) other diseases. Congenital disorders accounted for more than half of the cases (54.0%), including Down syndrome‒a chromosomal disorder that causes intellectual disability due to the triplication of chromosome 21 [36]; atrioventricular septal defect‒a congenital heart defect [37]; craniosynostosis‒a condition characterized by the premature and incomplete fusion of one or more cranial sutures, leading to an abnormal shape of the skull [38]; Cri-du-chat syndrome‒a genetic disorder resulting from a deletion on the short arm of chromosome 5, characterized by maxillofacial underdevelopment, developmental delay, and intellectual disability [39]; and Williams syndrome‒caused by a microdeletion of chromosome 7, resulting in developmental and physical abnormalities, including cardiovascular abnormalities, intellectual disability, and growth deficiency [40]. Neurological diseases represented 26.2% of the cases, including Lennox-Gastaut syndrome‒the most severe epileptic encephalopathy characterized by various seizures [41]; West syndrome‒presenting with infantile spasms and developmental delay [42]; status epilepticus‒wherein continuous seizures persist for prolonged periods or recurrent seizures occur without full recovery of consciousness [43]; and Duchenne muscular dystrophy‒a genetic disorder that causes muscle weakness and leads to delays in motor and language development [44]. Other diseases included Moyamoya disease‒a rare condition characterized by the progressive stenosis of brain arteries that can lead to stroke [45]; Mowat-Wilson syndrome‒ a genetic disorder associated with characteristic facial features, intellectual and developmental disabilities, and congenital malformations [46]; mucopolysaccharidosis‒ a group of rare lysosomal storage diseases caused by genetic defects, characterized by characteristic facial features, a large tongue, and intellectual impairment [47]; nonobstructive hypertrophic cardiomyopathy‒a genetic heart muscle disease [48]; and Rett syndrome‒a severe neurodevelopmental disorder characterized by developmental regression [49].

In this study, most pediatric patients with rare diseases underwent dental check-ups every 3 - 6 months, and 47.9% had received dental caries treatment within the past 6 months. Regular check-ups accounted for the predominant reason for dental visits (61.1%), followed by recommendations from primary physicians (32.5%). In contrast, visits prompted by symptoms such as difficulty eating or experiencing pain were less frequent (12.7% and 11.9%, respectively). The high proportion of preventive care visits suggests that many caregivers acknowledge the importance of dental care for children with rare diseases and actively engage in dental visits for preventive purposes. The relatively low proportion of visits provoked by symptoms may be attributed to caregivers recognizing the need for oral care or being encouraged by primary physicians to attend dental clinics for preventive purposes. Furthermore, limited communication capabilities among some children with rare diseases may hinder their ability to express symptoms, contributing to fewer prompted visits [20]. In fact, in this study, caregivers primarily acknowledged that children with rare diseases currently have poor oral health, which could adversely affect their overall health. However, caregivers also reported a lack of resources concerning various aspects of dental care, encompassing information on oral health, specialized dentists, specialized dental care facilities, and insurance coverage. These findings suggest that, despite recognizing the necessity of dental management for children with rare diseases, caregivers encounter challenges due to insufficient information, inadequate facilities, and limited support structures available to fulfill their needs. Moreover, more than half of the caregivers reported that their primary physician had not advised them to schedule dental check-ups or informed them about the importance of oral care for their rare disease. In contrast, caregivers receiving guidance or clarification from primary physicians were more inclined to pursue dental visits for preventive purposes. Consequently, it is essential to enhance access to relevant information concerning dental care for children with rare diseases and collaborate with pediatricians to promote preventive dental visits.

The primary reasons influencing the selection of a dental hospital included the expertise of the dental staff and collaborative care with pediatricians (54.8% and 52.4%, respectively), followed by dental equipment and facilities (39.7%). In contrast, geographical proximity was deemed less significant (11.9%). This suggests that caregivers prioritize factors such as the specialized dentists, collaborative relations with medical departments, and the accessibility of dental facilities and equipment suitable for addressing the unique needs posed by their child’s rare disease, rather than focusing on the hospital’s location. This highlights the necessity of training specialized dentists, fostering collaborative care with pediatricians, and establishing dental facilities equipped to manage and treat the specific challenges faced by patients with rare diseases. Therefore, it is necessary to establish specialized dental facilities, such as dental departments within rare disease centers or dental facilities that collaborate efficiently with related medical departments. Additionally, developing dental facilities with specialized infrastructure and equipment can improve accessibility for patients with physical impairments. Furthermore, training specialized dentists who are qualified as dental specialists and possess knowledge and clinical experi-ence in rare diseases would enable safer and more tailored dental care for these patients.

The most common barrier to accessing dental care cited was the lack of cooperation from the child (43.7%), followed by limited accessibility to specialized dental hospitals and refusal of treatment at primary care institutions (both at 30.2%). These results underscore the difficulties associated with providing dental care for children with rare diseases, attributed to cognitive and motor limitations, barriers in accessing specialized dental care at primary care institutions, and the shortage of specialized dental hospitals. This suggests the need to expand dental care facilities tailored to the needs of children with rare diseases.

Furthermore, among the factors perceived as challenges to dental visits, the financial burden stood at 19.1%, indicating that caregivers encounter substantial financial challenges. In terms of the economic burden of dental treatment for children with rare diseases, the most expensive procedures were general anesthesia and hospitalization (31.8%), followed by orthodontic and prosthetic treatments (30.2% each), restorative treatment (15.1%), endodontic treatment (10.3%), and fluoride application (4.8%). Patients with rare diseases are often treated under general anesthesia and require hospitalization due to anticipated difficulties with cooperation during dental procedures, attributable to cognitive and motor development impairments or the need for more complex treatments such as prosthetic treatment, and surgical procedures due to structural anomalies in the oral and maxillofacial region [20,35]. Consequently, the financial implications arising from general anesthesia and hospitalization can be considerable. Moreover, orthodontic and prosthetic treatments tend to be classified as high-cost procedures, particularly as they often remain outside the ambit of insurance coverage, thereby amplifying the financial impact on caregivers. In contrast, restorative and endodontic treatments are more likely to receive insurance coverage, with fluoride applications also being covered for patients who have brain lesions, intellectual disabilities, mental disorders, or autism, indicating that the financial burden associated with these treatments is comparatively lower. Regarding treatments that are considered to be covered by insurance, the three most frequently mentioned were prosthetic treatment (46.8%), orthodontic treatment (46.0%), and general anesthesia accompanied by hospitalization (36.5%), followed by restorative treatment (31.0%), endodontic treatment (21.4%), and fluoride application (18.3%). The financial burden and recognition concerning the necessity for insurance coverage tended to be greater for restorative treatments than for endodontic treatments, likely reflecting the higher frequency of restorative treatments compared to endodontic treatments [35] and the fact that a significant portion of restorative treatments remains uncovered by insurance. Caregivers whose children underwent dental caries treatment within the past 6 months were more likely to express a need for insurance coverage across all treatment modalities compared to those who did not, predominantly expressing a need for prosthetic and restorative treatments. This observation points to a heightened awareness among caregivers of patients recently undergoing dental caries treatment regarding the financial burden and insurance coverage needs related to prosthetic and restorative treatments. Therefore, the burden of non-reimbursable dental treatments is substantial, emphasizing the necessity for systems that provide insurance coverage or financial support for these treatments.

The findings from the satisfaction survey related to dental treatment indicated that many caregivers regarded dental care as having a positive influence on their children’s overall health. They also reported improvements in children’s pain, oral discomfort, and masticatory function, along with increased happiness for both the caregiver and the child. These findings align with existing literature on the impact of oral health among children with rare diseases on their quality of life and overall health and demonstrate the positive outcomes associated with dental care for patients with rare diseases, underscoring the need for more accessible and accommodating dental care measures for these children.

The most prevalent requests for improvements within the dental care system included increasing specialized dental care facilities (42.9%), expanding insurance coverage (38.9%), increasing specialized dentists (33.3%), facilitating collaborative care with pediatricians (25.4%), and enhancing the availability of oral health information (11.1%). Furthermore, those who had undergone dental caries treatment within the preceding 6 months were more likely to articulate a stronger need for expanded insurance coverage compared to those who had not, indicating that caregivers with recent dental treatment experiences possess a heightened awareness of the necessity for broader insurance provisions. These results highlight the deficiencies in specialized dental care facilities, insurance coverage, and specialized dentists for children with rare diseases, further emphasizing the need for efforts to address these challenges.

According to the classification of rare diseases, the caregivers of patients with congenital disorders reported a higher financial burden for orthodontic treatment than those with other diseases and emphasized the need for more specialized dentists. Patients with congenital disorders often experience oral and maxillofacial complications that frequently require orthodontic treatment [5,20], and the percentage of patients undergoing such treatment is higher than that in other disease groups [35]. However, in Korea, insurance coverage for orthodontic treatment is currently restricted to patients with cleft lip and palate and those with specific congenital anomalies, such as cleidocranial dysostosis, craniofacial dysostosis, Crouzon’s disease, and acrocephalosyndactyly [50]. As a result, the majority of orthodontic treatments remain uncovered, placing a substantial financial burden on caregivers. Furthermore, due to the heightened likelihood of dental complications, caregivers of patients with congenital disorders articulate a compelling need for dental professionals with specialized knowledge regarding rare diseases and their associated complications. Thus, the establishment of tailored support systems that comprehensively address the specific requirements of patients with rare diseases is of paramount importance.

This study has several limitations. First, it did not encompass caregivers’ perceptions of dental care for healthy children without rare diseases, thereby precluding a comparative analysis with a control group. Second, being a survey-based study, the potential for inaccuracies in responses exists due to factors such as careless answering or a lack of comprehensive understanding of the questions posed.

Despite these limitations, this study possesses several strengths. First, rare diseases impact a very small patient population; hence, investigating the perceptions and needs of caregivers for these patients is significant in itself and represents the first study of its kind. Second, as a nationwide multicenter cohort study focusing on the dental care status of pediatric patients with rare diseases, this research offers a representative overview of the situation in Korea.

The oral health of pediatric patients with rare diseases is closely intertwined with their overall health and quality of life, rendering dental care critically important for them. In fact, in this study, many caregivers of children with rare diseases reported experiencing positive changes, both functional and psychological, following dental treatment for their children. However, according to this study, in Korea, despite caregivers acknowledging the necessity of oral health care for children with rare diseases, challenges in providing adequate dental care persist, attributed to a lack of patient cooperation, insufficient oral care information, and a shortage of specialized dentists and facilities, compounded by limited insurance coverage. Caregivers emphasized the urgent need to enhance the dental care system for children with rare diseases by expanding specialized dental facilities, increasing the number of specialized dentists, enhancing insurance coverage, and fostering collaborative care with pediatricians. Furthermore, caregivers of patients with prior experiences of dental caries treatment stressed the necessity to broaden insurance coverage, especially for prosthetic and restorative treatments. Therefore, to improve dental care for children with rare diseases, it is essential to promote preventive dental visits in collaboration with pediatricians. Furthermore, tailored policies and comprehensive support systems are needed that include expanded insurance coverage, an increase in specialized dentists, and the expansion of specialized dental facilities.