Author:
Dr Aruna Tambuwala,
Professor and Head, Department of Oral And Maxillofacial Surgery

Abstract:
A 16 year old boy reported to the department of Conservative Dentistry and Endodontics, M. A. Rangoonwala Dental College, Pune with a chief complaint of dicoloured maxillary anterior teeth. Clinical and radiographic examination revealed a radicular cyst associated with an inverted mesiodens along with odontome in the maxillary anterior region. Endodontic treatment was performed for the maxillary anterior teeth followed by surgical extraction of supernumerary tooth, odontome and enucleation of the cyst. Seven months follow up reveals a satisfactory result as the patient is asymptomatic and healing is progressive.

Introduction:
Radicular cyst is the most commonly occurring odontogenic cyst of jaws usually associated with carious, non-vital or teeth which are exposed to trauma. It usually presents in the later age of life because the formation of the cyst is the last step in a progression of inflammatory events following a periapical inflammatory lesion. Supernumerary teeth are accessory teeth that result from hyperactivity of the dental lamina [1]. Almost all (98%) occur in the maxilla, mostly in the anterior palate [2, 3]. The most common type of supernumerary tooth as indicated by Alberti et al [4] is mesiodens. Mesiodens may occur as single, multiple, unilateral or bilateral.

Odontoma represents a hamartomatous malformation rather than a neoplasm. It is the most common odontogenic tumor, representing 67% of all odontogenic tumors.[5]

The following report presents the case of a 16 year old boy with a radicular cyst, an inverted mesiodens, odontome in maxillary anterior region and its surgical as well as endodontic management.

Case Report:

A 16 yr old boy reported to the department of Conservative Dentistry and Endodontics, M. A. Rangoonwala Dental College, Pune with a chief complaint of discoloured maxillary anterior teeth. Patient gives a history of trauma in the same region at the age of eight years. Clinical extraoral examination revealed no alterations. Intraoral examination revealed a malocclusion in the form of crowding in the maxillary anterior region.[Figure 1and 2] All four maxillary incisors were checked and confirmed to be non vital.

Figure 1: Intraoral view (labial)	Figure 2: Intraoral view (palatal)

Figure 3 : Radiographic picture of  Pre therapy; showing cystic lesion(A), mesiodens(B) and odontome(C) marked with arrows top to bottom

Radiographic examination revealed the presence of opaque, calcified mass resembling inverted mesiodens associated with an odontoma-like malformation. Radiolucent lesion was also found in association with right maxillary central and lateral incisor suggestive of a cyst.[Figure 3]
Patient was referred to the Department of Oral and Maxillofacial Surgery for opinion. An interdisciplinary approach was carried out. Endodontic therapy was planned for the maxillary anterior incisors. The teeth were access opened and calcium hydroxide placement was done for a period of 6 months, and within this period the calcium hydroxide dressing was changed once a month. The teeth were then obturated.

Figure 4 : Intra operativeview

Figure 5 : odontome, mesiodens specimen

Figure 6 : Enucleated cyst

Once the obturation was completed the patient was operated under local anesthesia. Enucleation of the cystic lesion, along with removal of inverted mesiodens and odontome was done.The root resection was done in relation to right maxillary central and lateral incisor as they were involved with the lesion. Root end preparation was doneup to 3mm for both the teeth using ultrasonic, followed by MTA placement in the prepared space.[Figure 4, 5 and 6]
Histological examination of the enucleated specimen confirmed the diagnosis of a radicular cyst.[Figure 7]

Figure 7: Histopathological picture

Figure 8: Clinical Post operative picture

Figure 9: Post operative radiographical picture

Seven months follow up reveals a satisfactory result as the patient is asymptomatic and healing is progressive. [Figure 8 and 9]

Discussion:

The treatment options for largeperiapical lesions range from conventional nonsurgical root canal treatment with long-term calcium hydroxide therapy tovarious surgical interventions. Intracanal medicaments areadvocated to eliminate remaining bacteria afterchemomechanical instrumentation, even in theinaccessible areas of the root canal system, reducesinflammation of the periapical tissues, dissolvesremaining organic material and counteracts coronalmicroleakage.Calcium hydroxide as intracanal medicament neutralizes the acid medium providing an environment for better healing.In the above case, the periapical lesion did not respond to theintracanal medicament because of the causative factorbeing located beyond the root canal system, within the inflamed periapical tissue, thus requiring surgical intervention.
Therefore, patients should undergo clinical and radiological evaluation for few months after theinitial root canal treatment, to verify resolution of the lesion.
A Radicular cyst, also known as a periapical cyst is the most common dental cyst [6]. It is defined as a cyst about the root of a dead tooth, usually caused by dental caries or disease of the pulp. It is found in 50.7% out of 2057 patient enrolled in a survey of oral biopsies performed in an oral surgical centre in Singapore from 1993-97 [7].The development of the cyst is caused by the growth of remnants of Malassez cells involved in the development of the dental organ. It usually goes unnoticed because of the nature and size of the cyst is small. In this case, the size of the cyst is around 3 x 2.5 cm in size [8].
The term ‘odontoma’ refers to any tumor of odontogenic origin. An odontome is a growth in which both epithelial and mesenchymal cells exhibit complete differentiation with the result that functional ameloblasts and odontoblasts form enamel and dentin [9].Odontoma represents a hamartomatous malformation rather than a neoplasm. It is the most common odontogenic tumor, representing 67% of all odontogenic tumours. The odontoma seems to result from budding of extra-odontogenic epithelial cells from the dental lamina. At first, there is resorption, so the lesion is radiolucent. The most radiopaque stage is when calcification of dental tissues is complete. The most common type is compound odontome which comprises of odontogenic tissues laid down in a normal relationship. The resulting structure bears considerable morphologic resemblance to teeth. Complex odontomes are formed when tooth components are not well organized and tooth-like structures are not formed. Some 62% of the compound variety of odontome occurs in maxilla, having predilection for the incisor canine region but with no gender bias. The complex odontomes are more common in the mandible and approximately 68% of complex odontomes occur in female patients [10]. In present case, one of the finding is a complex odontome found in the maxillary anterior region in a male patient, which is uncommon. According to Kaugars et al. (1989), odontomas were found to be in association with an unerupted tooth in 48% of cases and in conjunction with a cyst in 28% of cases [11].
The term ‘mesiodens’ was coined by Bolk (1917) to denote an accessory or supernumerary tooth situated in between the maxillary central incisors [12]. The presence of a mesiodens should be suspected if there is delayed eruption of the permanent incisors or if the central incisors are displaced, malposed or exhibit spacing. Resorption of rootsadjacent to a supernumerary may occur but it is extremely rare [13]. Its incidence is estimated to be between 46 & 67 % of all supernumerary teeth.  A mesiodens is a supernumerary tooth located in the maxillary central incisor region. The overall prevalence of mesiodens is between 0.15% to 1.9%.[14,15]of the 85 mesiodens reported by Gunduz K et al, 67 were fully impacted, six were partially erupted & 12 were fully erupted. It has been stated that only 25% of maxillary anterior supernumeraries erupt [16].Depending upon the interplay of these factors, the shape of the mesiodens becomes evident at the bell stage. However, being an accessory tooth, in an already crowded nasomaxillary complex, the tooth germ is subject to physical pressure which can modify its shape and orientation leading to displacement kind of growth movements. This is particularly true for inverted supernumerary tooth which is seen in our case [17].

 

Conclusion:
In summary, radicular cyst developmentalong with impacted inverted supernumerary teeth and odontome in association is rare. Hence in such cases careful evaluation is required. Early endodontic therapy followed by surgical intervention without any unnecessary delay is of major important for successful results.

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