Palatally erupted twin mesiodens - A case report with literature review

INTRODUCTION

The term mesiodens was coined by Balk in 1917 to indicate a supernumerary tooth located between two central incisors.¹ According to Mosby’s Medical Dictionary, “Mesiodens is defined as a supernumerary erupted or a unerupted tooth that develops between two maxillary central incisors.² The incidence of occurrence of mesiodens is 0- 1.9% for deciduous teeth and 0.15 -3.8% for permanent teeth with a male to female prevalence ratio of 2:1.³ Mesiodens can be classified according to their position, occurrence, eruption pattern, and orientation, and thereby, it may be unilateral or bilateral, isolated or associated with syndromes such as cleft lip and palate, cleidocranial dysostosis, Down’s syndrome and Gardner syndrome, erupted or unerupted or partially erupted, or it may be straight, rotated or inverted.⁴ In this paper we describe clinical features, radiographic features and management of non-syndromic twin mesiodens in a 20 year old female patient.

Case Report

A 20 year old female patient reported to the department of Oral Medicine and Radiology with complaint of additional teeth in the upper front region of jaw, which interfered with the speech and mastication. She also complained of proclined upper front teeth and had esthetic concern about the same. Medical history was non-contributory. None of the family members had similar dental problems. Patient was moderately built and nourished. There was no extraoral abnormality, patient had convex profile, there was proclination of upper anteriors causing incompetent lips (figure 1). Intraoral examination revealed presence of two completely erupted conical mesiodentes on the palatal aspect of 11 and 21 (figure 2). Complete set of teeth were present from 11 to 17, 21 to 27, 31 to 37 and 41 to 47. However there was over retained 85 and 45 was lingually erupted (figure 3). She had bilateral class 1 molar relation with proclined maxillary anteriors and mild generalized enamel hypoplasia. A provisional diagnosis of twin mesiodentes and Angles class 1 malocclusion was given

Patient was then advised OPG to see the morphology of roots of mesiodens and to exclude presence of any other pathology. OPG showed well defined conical radio opaque mesiodentes superimposing on 11 and 21 (figure 4).

The mesiodentes and over retained 85 were extracted. Figure 5 and figure 6 shows immediate post extraction socket and the extracted mesiodentes respectively. Orthodontic treatment was planned after healing of the socket.

DISCUSSION

Mesiodens is commonly diagnosed in first decade of life. The theory, involving hyperactivity of the dental lamina, is the most widely supported one. According to this theory, remnants of the dental lamina or palatal offshoots of active dental lamina are induced to develop into an extra tooth bud, which results in a supernumerary tooth.⁵ Their presence may lead to various complications such as delayed eruption, malposition and impaction of permanent incisors; crowding, spacing, median diastema, rotation and root resorption of the adjacent teeth or even eruption of incisor in the nasal cavity and cyst formation.⁶

Though mesiodens is the commonest supernumerary teeth, occurrence of twin mesiodens is not common. In the present case we reported two palatally erupted mesiodens that caused difficulty in speech and proclination and overlapping of the central incisors. Karthik Venkataraghavan reported case of twin mesiodens present palatal to 11 and 21 resulting in protrusion and spacing of the maxillary central incisors.⁷

Asha ML reported case of twin mesiodentes present palatal to 11 and 21 resulting in rotation of the maxillary central and lateral incisors.⁸ Shruti Srinivasan reported a case of twin mesiodens two conical mesiodentes present palatal to 11 and 21 resulting in proclination of the maxillary central incisors and difficulty in speech.⁹ Gowri Sankar Singaraju reported case of twin mesiodens one labial and one palatal giving a floret appearance and causing proclination and rotation of permanent central incisors¹⁰. Amrita Sujlana reported two cases of twin mesiodens in a 12 years and 8years old patient respectively. In one patient both mesiodentes were erupted causing impaction of permanent maxillary central incisors and in other patient there was one erupted and one unerupted mesiodens.¹¹

AD Dinkar, reported a case of impacted mesiodentes which were associated with dentigerous cyst causing pain and swelling in the maxillary anterior region.¹² Gharote et al reported 6 cases with twin mesiodentes, in which one case had two impacted mesiodentes and other had one erupted and one unerupted mesiodens. In the remaining 4 cases the twin mesiodentes were erupted. These caused impaired occlusion and trauma to tongue. In one cases the mesiodentes was asymptomatic and in other case they were discovered as incidental findings during radiographic examination.¹³ Canoglu E et al reported a case of 2 unerupted inverted mesiodentes causing rotation of maxillary permanent incisors.¹⁴ Carla Vecchione Gurgel reported Bilateral Mesiodens in 9 years Monozygotic Twins who were referred for impacted maxillary central incisors. In both twins radiographic investigation revealed there were two conical mesiodens in the path of the permanent central incisors in both the twins.¹⁵

R P Sedon reported unerupted bilateral mesiodentes in 7 yeras old afro-carebian monozygotic twins.¹⁶ Jafri et al reported a case with two supernumerary teeth, one being an inverted impacted mesiodens, placed high in the palate and the other a partially erupted, rotated mesiodens in maxillary left anterior region associated with delayed eruption of permanent maxillary left central incisor.¹⁷

Diagnosis of the erupted mesiodentes is easy and through clinical examination. Unerupted mesiodens are diagnosed based on clinical and radiographic features. Intraoral periapical radiographs, occlusal radiographs and OPG are conventionally used for the diagnosis of mesiodens. However to know the precise location of mesiodens and their relation with the adjacent permanent teeth advanced imaging like CBCT may be needed.

Treatment of a mesiodens usually involves extraction. Some have suggested that an impacted supernumerary should be extracted only if it is associated with pathosis, while others have suggest removal regardless of the absence of disease.¹⁸

Treatment protocol of mesiodens depends upon location and the orientation of a mesiodens, and associated pathology. Studies have shown that the removal of a mesiodens during the early mixed dentition stage allows normal eruptive forces to promote spontaneous eruption of the impacted tooth after 6 to 24 months.⁵

Mesiodens is managed either by extraction or by the conservative method of retention and observation. Extraction may be of three types: immediate, early and late. Early or late extraction depends on intervention before or after root formation of permanent incisors.¹

Yagüe-García et al. favored early extraction to prevent complication19 but many authors discouraged it for chance of iatrogenic damage to the developing permanent incisors during extraction.^20,21 Delayed extraction is recommended around the age of 10 years²¹In the present case the twin mesiodentes were diagnosed at the age of 20yrs and there was complete root formation. They were treated by extraction following which orthodontic treatment was planned.

CONCLUSION

Twin mesiodentes are uncommon and may cause various functional and aesthetic problems. Early diagnosis and intervention is important to prevent associated complications. Radiographs play an important role in diagnosis and management. In the present case we reported case of palatally erupted twin mesiodentes causing difficulty in speech and proclination of central incisors making the patient to seek the treatment. The case was managed by extraction of both the mesiodens followed by initiating orthodontic treatment.