A Rare Case Report of Four Bilateral Maxillary Lateral Incisors in a Non-Syndromic PatientKey Clinical Message Bilateral supplemental maxillary lateral incisors in non-syndromic adults are exceptionally rare. Accurate clinical and radiographic assessment, careful identification of supernumerary teeth, and individualized treatment planning are essential to address crowding, restore occlusion, and optimize esthetic and functional outcomeKeywords: Tooth Supernumerary, Supplemental Tooth, lateral incisors, hyperdontia.IntroductionDental anomalies related to tooth number, shape, and size can occur in both primary and permanent dentitions. Supernumerary teeth may arise from genetic, environmental, or multifactorial causes, although the precise etiology remains incompletely understood.1 The prevalence of supernumerary teeth in the permanent dentition ranges from 0.1% to 3.6%, with a predilection for the maxilla.1-3 Mesiodens and paramolars are the most frequently observed types and are more common in males.1,4,5 Supernumerary teeth can cause complications such as crowding, rotation, diastema, eruption disturbances of adjacent teeth, root resorption, and periodontal pathology.6Given the extreme rarity of four bilateral maxillary lateral incisors in non-syndromic individuals and the limited number of reported cases, this study aims to document this unusual presentation and increase clinician awareness. Reporting such cases may also provide valuable information for future research in dental genetics and epidemiology.Case PresentationA 34-year-old male patient with no systemic disease or syndromic features presented for orthodontic treatment. Clinical examination revealed four bilaterally symmetrical maxillary lateral incisors (figure 1,2). The patient demonstrated anterior open bite and posterior crossbite in the premolar region (figure 2,3), with moderate crowding in the maxilla and mild crowding in the mandible (figure 4). Several molars had been previously extracted (figure 4). Panoramic radiography confirmed the presence of supernumerary teeth with independent roots, and gemination was excluded (figure 5). A lateral cephalometric radiograph was also obtained as part of the pre-orthodontic diagnostic records (figure 6).Treatment Planning and ManagementFollowing posterior maxillary expansion, the supernumerary lateral incisors adjacent to the canines were extracted. Fixed orthodontic therapy was employed to align the dentition and establish bilateral Class I canine relationships. The selection of teeth for extraction was guided by their position, eruption status, and the diagnostic challenge of distinguishing between normal and supernumerary teeth. This approach reduced treatment complexity and duration while facilitating optimal occlusal outcomes.Results and Follow-UpAfter 18 months of treatment (figure 7-9):The dentition was aligned, and smile esthetics improved.Anterior open bite was resolved.Bilateral Class I canine relationships were achieved.The patient was referred for esthetic rehabilitation with veneers or laminates and replacement of missing molars.Long-term follow-up was recommended to assess treatment stability.DiscussionSupernumerary teeth are most commonly observed as solitary teeth in the anterior maxilla. The simultaneous presence of bilateral supplemental lateral incisors, as in this case, is exceedingly rare.7 Several etiologic theories have been proposed, including atavism, dental lamina hyperactivity, and bud splitting, with the hyperactive dental lamina theory being the most widely accepted. Genetic factors likely play a significant role.6,8,9Previous reports have predominantly described unilateral or bilateral supplemental lateral incisors associated with crowding, ectopic eruption, or esthetic concerns, often in younger patients or during the mixed dentition phase.10-12 In contrast, the present case involved a fully adult patient with complete permanent dentition who had not previously recognized the supernumerary teeth.Clinically, the patient exhibited only anterior crowding, adjacent tooth rotations, and esthetic disturbances, with no pathological complications such as cyst formation or root resorption. The absence of syndromic features differentiates this case from conditions such as cleidocranial dysplasia or Gardner syndrome. Morphological similarity between the supernumerary and normal lateral incisors complicated clinical identification, although radiographic evaluation helped exclude gemination.Treatment decisions for supernumerary teeth depend on eruption status, position, and associated complications. Some studies advocate early extraction to prevent malocclusion, while others recommend observation in asymptomatic cases.13 In this case, extraction of the lateral incisors adjacent to the canines was performed to manage space and facilitate Class I canine relationships, resulting in reduced treatment duration and favorable functional and esthetic outcomes.Given the rarity of four bilaterally symmetrical maxillary lateral incisors in non-syndromic individuals and the paucity of published reports, this case provides a detailed documentation of this anomaly and raises clinician awareness. Reporting such cases may serve as a valuable reference for future studies in dental genetics and epidemiology, and provide practical guidance for clinical management of supernumerary teeth.ConclusionThe presence of four bilateral maxillary lateral incisors in a non-syndromic individual is extremely rare and may pose challenges in orthodontic diagnosis, treatment planning, and achieving ideal occlusion and esthetics. This case highlights the importance of thorough clinical and radiographic assessment, emphasizing patient-centered treatment decisions that consider functional and esthetic needs. Interdisciplinary approaches involving collaboration with other dental specialists may further enhance clinical outcomes and patient satisfaction.Ethical ConsiderationsWritten informed consent was obtained from the patient for the publication of clinical information and images. All images were anonymized, and the patient’s identity was protected.Conflict of Interest: There are no conflicts of interest.Data availability: Data supporting this study are available from the corresponding author upon reasonable request.Author contribution: Seyed-Mohsen Hosseini-Adib (patient treatment, clinical supervision)Mona Kazemi: (manuscript writing, literature review)Funding: The authors received no financial support for the authorship or publication of this article.