Fused Tooth Causing Gingival Issue and Pain: A Case Report in a 26-Year-Old American Male

   

Krisha Shah^1*, Dhara Shah² and Ana Keohone³

Citation: Shah K, Shah D, Keohone A. Fused Tooth Causing Gingival Issue and Pain: A Case Report in a 26-Year-Old American Male. J Oral Med and Dent Res. 6(3):1-07.

Received: December 02, 2025 | Published: December 27, 2025                                                 

Copyright©️ 2025 Genesis Pub by Shah K. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC BY 4.0). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author(s) and source are properly credited.

DOI: https://doi.org/10.52793/JOMDR.2025.6(3)-108

Abstract

A fused tooth is a developmental anomaly where two adjacent tooth buds join together during development to form a single, abnormally large tooth with a reduced number of teeth in the arch. This can also occur when a normal tooth germ fuses with a supernumerary (extra) tooth germ. The appearance can vary, from a large crown with a groove or indentation to separate roots, depending on how late the fusion occurred. While it is generally asymptomatic, fusion can sometimes cause complications such as pain, periodontal inflammation, caries susceptibility, and esthetic concerns. This case report presents a rare occurrence of fusion involving a permanent maxillary molar in a 26-year-old American male. The patient presented with localized gingival irritation and intermittent pain in the affected region. Detailed clinical and radiographic assessment confirmed the diagnosis of tooth fusion. Surgical management was undertaken, which successfully resolved the symptoms and restored the patient’s comfort and oral health. This case emphasizes the significance of prompt diagnosis, thorough clinical evaluation, and an interdisciplinary approach in managing developmental dental anomalies such as fusion.

Keywords

Fusion; Maxillary molar; Gingival inflammation; Developmental anomaly; Tooth pain.

Introduction

Dental anomalies refer to deviations from the normal number, size, shape, structure, or eruption pattern of teeth and are commonly classified into five major categories: number, size, shape, structure, and eruption disturbances (Figure 1).

Dental anomalies are broadly divided into disturbances in number, size, shape, structure, and eruption, each resulting from developmental irregularities during tooth formation. Anomalies in number—such as missing teeth (hypodontia, oligodontia, anodontia) and supernumerary teeth—are well-documented in developmental reviews [1]. Size anomalies like macrodontia and microdontia arise from abnormalities in tooth morphogenesis and are commonly highlighted across clinical literature [2]. Shape anomalies include gemination, fusion, concrescence, dilaceration, talon cusp, dens invaginatus (dens in dente), and taurodontism, all of which represent structural deviations occurring during morpho differentiation [3]. Structural anomalies such as amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia result from hereditary defects affecting enamel or dentin mineralization [4]. Disturbances in eruption—including delayed eruption, premature eruption, and transposition—are influenced by local or systemic factors and have been described in recent radiographic and epidemiological studies [5]. Together, these sources provide comprehensive scientific support for the classification and understanding of dental developmental anomalies [6].

Among the anomalies affecting tooth shape, tooth fusion is a rare developmental condition resulting from the union of two adjacent tooth germs during odontogenesis, leading to the formation of a single enlarged tooth structure with conjoined dentin and, occasionally, pulp chambers [7].

Fused teeth typically present as an enlarged crown, sometimes with a vertical groove separating the two developmental components, and may exhibit a reduced or increased tooth count in the dental arch—a key feature that differentiates fusion from gemination as per (figure 2) [8]. The condition may occur in both primary and permanent dentitions, with a higher incidence in the anterior region of the maxilla, especially involving central and lateral incisors [9,10]. Unilateral fusion is most frequently observed, whereas bilateral cases are uncommon [11,12].

Clinically, fused teeth can pose both aesthetic and functional challenges, including malalignment, crowding, and occlusal discrepancies. Additionally, the deep developmental grooves along the junctional area tend to favor plaque accumulation, predisposing the site to localized gingival inflammation and caries formation [13,14]. The complex internal morphology—often characterized by an irregular pulp chamber or multiple root canals—can complicate endodontic or restorative treatment [15].

Several studies have highlighted an increased risk of pulpal and periodontal complications in fused teeth compared with normal dentition, particularly when the fusion extends to the root level [16,17,18]. Early diagnosis and preventive management, such as sealant application, plaque control, and periodic monitoring, are therefore essential to reduce the risk of caries and associated pathology [19,20,21].

Formation: Fusion can be complete or incomplete.

• Complete fusion: Happens early in development and may result in a single large crown that takes up the space of two teeth.
• Incomplete fusion: Occurs later in development and can result in separate pulp chambers and root canals, but the roots are joined [22].

 

Radiographic evaluation plays a crucial role in diagnosing tooth fusion, as it helps identify the presence of two distinct pulp chambers or root canals within a single enlarged tooth structure, confirming the union of two tooth germs [8]. Management strategies depend on the extent of fusion, pulpal involvement, esthetic considerations, and associated periodontal or occlusal complications. Treatment options may include preventive sealing of developmental grooves, restorative correction, endodontic therapy in complex cases, or surgical separation or extraction when symptoms persist or functional and esthetic compromise is significant.

This case report presents a rare instance of fusion involving a permanent maxillary molar in a 26-year-old male patient. The condition was associated with localized gingival inflammation and intermittent pain. The report emphasizes the clinical characteristics, diagnostic challenges, and surgical management approach undertaken to achieve a successful outcome.

Figure 1: Classification of different tooth anomalies.

Figure 2: Difference between Fusion and Germination.

Case Report

A 26-year-old male patient reported to our dental clinic with complaints of persistent gum pain and swelling in the posterior maxillary region. The patient had no significant medical history and reported good general health.

Clinical examination revealed localized gingival inflammation and tenderness on palpation in relation to the right maxillary upper 1st molar. A distinct bulge was noted on the occlusal surface, and a vertical developmental groove extended from the incisal edge toward the gingival margin. The tooth appeared larger mesiodistally compared to the contralateral molar.

Radiographic examination using intraoral periapical showed a single enlarged tooth crown with two teeth fused at the crown area, consistent with a diagnosis of fusion. No periapical pathology was noted (as per Figures 3 and 4).

Figure 3: Clinical photograph showing a bifid crown and gingival swelling associated with the maxillary upper molar.

Figure 4: Intraoral periapical radiograph suggestive of fusion.

Treatment plan

Initial treatment focused on non-surgical periodontal therapy, including professional scaling and root planning, along with antimicrobial mouth rinses and systemic antibiotics. Despite temporary relief, symptoms persisted due to the presence of a deep developmental groove acting as a plaque trap and periodontal irritant.

A surgical intervention was planned to address the underlying cause. The fused molar was extracted under local anesthesia, followed by debridement and thorough irrigation of the affected socket. Post-operative care included antibiotics, analgesics, and oral hygiene instructions. The patient was advised on prosthetic options for tooth replacement during follow-up.

Outcome

At two-week and one-month follow-up appointments, the patient reported complete resolution of pain and swelling. Healing was good, and the extraction site showed satisfactory soft tissue regeneration. (Figure 5) After a follow-up appointment, the patient expressed satisfaction with the outcome and opted for a delayed prosthetic restoration.

Figure 5: post-op radiograph with 6-month healing.

Discussion

Dental anomalies such as fusion pose diagnostic and therapeutic challenges. Differentiating between fusion and germination is critical and relies on tooth count and radiographic interpretation. Fusion teeth often present esthetic concerns or functional limitations, especially if associated with deep grooves susceptible to plaque accumulation and periodontal compromise.

In the present case, the deep labial groove associated with the fusion led to gingival inflammation and pain, unresponsive to conservative periodontal therapy. Surgical extraction provided definitive relief, underlining the importance of a tailored treatment plan based on symptom severity and patient preference.

Previous studies have emphasized that fusion teeth, although rare, should be considered in the differential diagnoses of gingival swelling or unusual tooth morphology. A multidisciplinary approach involving clinical evaluation, radiographic analysis, and surgical management, when necessary, ensures successful outcomes [22].

Conclusion

This case illustrates a rare presentation of a fusion of upper 1st maxillary molars causing gingival inflammation and discomfort in a young adult male. Prompt diagnosis and intervention led to a favorable clinical outcome. Dental professionals should maintain a high index of suspicion for developmental anomalies during routine examinations, particularly when patients present with atypical tooth morphology and unexplained periodontal symptoms.

Source of support

None

Conflict of Interest

None declared.

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