Mesiodens

Clinical case

An 8-year-old child is referred because the upper right central incisor has not erupted. The upper left central incisor erupted 12 months earlier. There is a midline diastema and a retained primary incisor. An upper occlusal radiograph shows a conical tooth-like structure in the midline.

Pathophysiology

A mesiodens forms due to localised abnormal proliferation of the dental lamina in the anterior maxilla. It may obstruct the eruption path of a permanent central incisor, causing delayed eruption, displacement, rotation or a midline diastema.

Epidemiology and Risk Factors

Clinical Features

A mesiodens is a supernumerary tooth located in the maxillary midline, usually between the maxillary central incisors. It is commonly conical and may be erupted or unerupted.

Symptoms	Signs	Image
Failure of eruption of maxillary incisor	Delayed eruption of maxillary central incisor
Midline diastema	Retained primary incisor
	Rotation or displacement
	Palatal or labial swelling
	Conical erupted tooth

Investigations

Primary investigations:

• Full medical and dental history

• Clinical examination

• Radiographs: periapical radiograph; upper occlusal radiograph may be used to localise anterior supernumerary teeth; OPG can be used to assess the full dentition

Gold standard investigation:

Diagnosis is by radiographic identification of a midline supernumerary tooth, combined with clinical findings.

Investigations to consider:

• Cone beam CT for more precise localisation

• Orthodontic assessment

Differential diagnosis