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A review of 47 cases of unerupted maxillary incisors.

OBJECTIVES
To study the prevalence of aetiological factors associated with unerupted maxillary incisors and to follow the outcome of treatment in a study of 47 cases.


DESIGN
A retrospective study.


SETTING
The Dental Department, St Luke's Hospital, Malta, the School Dental Clinic of Malta and the private practices of two orthodontists in Malta.


SAMPLE AND METHODS
Forty-seven patients with a total of 53 unerupted maxillary incisors were classified according to the aetiological factors causing non-eruption. The relative prevalence of the various aetiologies were ascertained, and the outcome after treatment was recorded to assess the efficacy of the treatment methods being used.


RESULTS
The most common cause of lack of eruption was the presence of supernumerary teeth (47% of patients). The other 53% of cases were distributed more or less equally between the remaining aetiological factors, which were odontomes (9%), dilacerations (9%), tooth germ malposition (12%), crowding (4%), one case of a calcifying odontogenic cyst (2%) and one case of trauma to the preceding deciduous tooth (2%). The aetiology of 15% of cases could not be ascertained. Once supernumerary teeth were removed, maxillary incisors usually erupted successfully with the help of conventional treatment methods such as surgical exposure and orthodontics. A relatively large number of incisors that failed to erupt due to other aetiological factors had to be extracted.


CONCLUSIONS
Maxillary incisors that fail to erupt due to the presence of supernumerary teeth have a better prognosis than unerupted incisors with less common aetiologies.