Surgical enucleation of radicular cyst in endodontically treated primary mandibular molar

Abstract

Radicular cysts are most common odontogenic cysts seen in the orofacial region, but not commonly detected in paediatric cases. This case report describes the accidental detection of radicular cyst and its surgical management in an 8-year-old boy in lower left back region of the jaw. The article also gives an insight about radicular cyst from its aetiology to the various other treatment modalities.

Background

Children exhibit many pathological lesions involving the jaw bones, among them odontogenic cysts constitute a major aspect of oral and maxillofacial pathology. The origin of these odontogenic cysts is allied with the development of the dental apparatus. Radicular cyst is also recognised as periapical cyst, apical periodontal cyst, root-end cyst or dental cyst and is derived from the inflammatory activation of epithelial root sheath residues of Malassez.¹

A common sequelae of dental caries, radicular cyst is the most common lesion of inflammatory origin. It usually arises within a periapical granuloma relating to stimulation resulting from a necrotic tooth. In literature the incidence of radicular cyst is rare, although dental caries is more common in paediatric population.^{2 3} Probably because these inflammatory cysts remain unnoticed as they are asymptomatic in nature. They are accidentally detected during routine radiographic examination or if acute exacerbation of this cystic lesion occurs and leads to the development of clinical signs and symptoms.

This article presents the surgical management of one such accidentally detected radicular cyst associated to a deciduous tooth.

Case presentation

An 8-year-old boy visited the paediatric dentistry department for his regular dental check-up. The patient underwent dental treatment in a private clinic a year ago. The patient mentioned that he felt the bulge with that tooth 15 days ago, but did not report as no change in size or pain was associated.

On extraoral examination, symmetrical face was observed (figure 1) and during intraoral inspection, slight gingival bulge was seen with the previously restored (pulpectomy with unknown material followed by stainless steel crown prosthesis) deciduous mandibular left second molar (75) tooth. On palpation, a diffuse swelling was seen on the left body of the mandible extending from the mesial aspect of deciduous mandibular left first molar (74) tooth and limiting until the mesial margin of permanent mandibular left first molar (36) tooth. The swelling was non-tender, firm in consistency, approximately 2×1 cm in size and oval in shape, and with no local rise in temperature. The noticeable expansion was seen to be associated with restored 75 tooth (figure 2).

Figure 1.

Extraoral image of the mandible.

Figure 2.

Intraoral image of the mandible.

Presence of diffuse swelling with previously restored tooth was suggestive of possible reinfection or cystic lesion formation. On radiographic investigations, IOPA showed well-defined radiolucency with 75 along with resorption of distal root with 74. The occlusal radiographic view depicted the extension of the lesion and the amount of cortical plate expansion (figure 3).

Figure 3.

Intraoral radiograph depicting the lesion.

Provisional diagnosis of radicular cyst with 75 was given after clinical and radiographic evaluation. Before commencement of the surgery, routine haemodynamic tests were performed and bleeding time, clotting time and haemoglobin levels were recorded. A written parental permission was obtained prior to the surgery.

Under all aseptic conditions the procedure was undertaken in the dental operatory. Local anaesthesia (2% lidocaine with epinephrine 1:80 000) was administered for the lower left arch (inferior alveolar, lingual and long buccal nerve block). Horizontally intrasulcular incision and vertically releasing incisions were given from mesial aspect of permanent mandibular left lateral incisor (32) to the distal aspect of 36 with the help of no 15 surgical blade (figure 4). A full thickness mucoperiosteal flap was raised buccally followed by extraction of 75 and 74 teeth (figures 5 and 6). Blunt dissection was conducted in the extraction socket area to evaluate the cyst’s extent and its fixation to the underlying structures. The cystic lesion was in proximity with the erupting premolars (figure 7). A thin buccal cortical plate was removed during the procedure so that cystic lesion could be appreciated near the erupting premolar. The lesion was enucleated and surgical zone was cleaned and irrigated with Betadine and saline (figures 8–10). The site was sutured back with 3/0 vicryl resorbable sutures (Ethicon) to achieve a complete primary closure (figure 11).

Figure 4.

Horizontally intrasulcular incision and vertically releasing incisions given.

Figure 5.

Mucoperiosteal flap raised.

Figure 6.

Extracted involved deciduous molars.

Figure 7.

Postextraction cystic area.

Figure 8.

Surgical enucleation of the cyst.

Figure 9.

Surgical area cleaned with Betadine.

Figure 10.

Enucleated cyst.

Figure 11.

Sutures placed.

The enucleated cystic lesion was stored in 10% formalin and sent for further histopathological examinations. Suture removal was done after 7 days and alginate impression was made (figure 12). Subsequently, a lingual arch space maintainer was constructed and placed (figure 13). The patient and his parents were instructed on maintenance of oral hygiene.

Figure 12.

Sutures removed.

Figure 13.

Space maintainer placed.

Outcome and follow-up

The patient had monthly appointments for follow-up, revealing uneventful healing of the surgical site. Eruption of both the premolars was seen on 10 months follow-up (figures 14 and 15).

Figure 14.

Follow-up after 10 months.

Figure 15.

Radiograph follow-up after 10 months.

Discussion

Radicular cyst is an accidental finding, seen in association with either carious or endodontically treated tooth. Clinically, these lesions are associated with non-vital tooth. Radiographically, the lesion can be a well-defined unilocular radiolucency (>2 cm in diameter) in the periapical region. However, histopathological study is considered the gold standard to confirm the final diagnosis of radicular cyst.^{1 4}

In the present case, the histopathological examination illustrated cystic lumen lined by non-keratinised stratified squamous epithelium. The analysis revealed significant infiltration of inflammatory cells comprising lymphocytes, plasma cells, macrophages and neutrophils confirming the diagnosis of radicular cyst.

Radicular cysts are most commonly seen in the mandibular molars due to increase prevalence of caries. Deciduous teeth remain for a short duration in the oral cavity and thus, these lesions are unnoticed and rare in the paediatric age group as it gives asymptomatic representation.

Trauma, carious tooth, periodontal infection or infection extruding the apex can be the aetiological factors of radicular cyst. These arise from epithelial residues in the periodontal ligament usually after the death of dental pulp. In the present case, the lesion was associated with endodontically restored tooth. Literature shows that the pulpal medicaments, either phenolic or non-phenolic containing obturating materials react with the apical area which may be responsible for the cyst development.^{5 6} The pulpal therapeutic agent (unknown obturating material as the patient failed to get his past records) within the canal causes antigenic stimulation in the periapical area which causes unusual proliferation and cyst formation.

Radicular cyst can be managed through either conservative or surgical approach. Conservative or non-surgical method depends on the chemomechanical preparation of the root canal and long-term intracanal medication for the suppression and healing of the lesion. This is a possible option for permanent teeth. Enucleation is considered as an optimal treatment option for managing radicular cyst in deciduous dentition. Enucleation procedure entails complete resection of the radicular cyst through careful dissection and ensuring that the affected tooth is to be removed along with the lesion before primary closure of the wounds. This procedure is undertaken to reduce the chances of recurrence and does not hamper the succedeneous tooth. Also, young growing individuals have high propensity for bone regeneration, leading to faster healing of the postsurgical osseous defects.⁷ Marsupialisation on the other hand is a more conservative surgical intervention undertaken to prevent damage to neighbouring anatomical structures. However, the major drawback of pathological tissue that can be left in situ along with multiple follow-up visits should not be ignored.⁸

Bone generation to fill the surgical defect is the primary goal during wound healing when large wounds are considered. The options available can be autologous bone, allografts, and xenografts and synthetic materials such as bioactive glass. Dhote et al used platelet rich fibrin for bone regeneration and found healing within the duration of 6 months.⁸ However, due to low patient compliance bone regeneration aids were not used and conventional method for healing was observed. The healing was relied on patient’s young age and excellent regeneration potential of bone at this stage.

Learning points.

• Radicular cysts are rare lesions occurring in the paediatric age group but are important to diagnose and consider proper treatment option for the holistic well-being of the patient.

• Patient’s history is the most important and even the slightest information should not be neglected.

• Educate your patients post any pulpal treatment about the cystic sequalae and should not be left unnoticed.

Ethics statements

Patient consent for publication

Consent obtained from the parent(s)/guardian(s).