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Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children.

BACKGROUND
The permanent canine tooth in the upper (maxillary) jaw sometimes does not erupt into the mouth correctly. In about 1% to 3% of the population these teeth will be diverted into the roof of the mouth (palatally). It has been suggested that if the deciduous canine is removed at the right time this palatal eruption might be avoided.


OBJECTIVES
To evaluate the effect of extracting the primary maxillary canine on the eruption of the palatally ectopic maxillary permanent canine.


SEARCH STRATEGY
We searched the Cochrane Oral Health Group's Trials Register (to April 2008); CENTRAL (The Cochrane Library 2008, Issue 3); MEDLINE (1966 to April 2008); EMBASE (1980 to April 2008). There were no language restrictions. Authors of trials were contacted for further data.


SELECTION CRITERIA
Trials were selected if they met the following criteria: a randomised or quasi-randomised controlled trial, involving the extraction of the primary maxillary canine and assessing eruption/non-eruption of the palatally displaced maxillary permanent canine.


DATA COLLECTION AND ANALYSIS
Seven review authors independently, in duplicate, examined the studies found in the search. The primary outcome was the reported prevalence of eruption or non-eruption of the ectopic permanent canine into the mouth following observation or intervention. Results were to be expressed as risk ratios for dichotomous outcomes with 95% confidence intervals and mean differences for continuous outcomes. Heterogeneity was to be investigated, including both clinical and methodological factors.


MAIN RESULTS
The search identified 324 publications of which 295 were excluded after reviewing the abstract. Full articles were obtained for the remaining 31, of which 19 were non-English and required translation. Three reports of two randomised controlled trials were identified for possible inclusion in the review; however, the data in the publications were not presented in a form that could be usable and the authors have been contacted for further details.


AUTHORS' CONCLUSIONS
There is currently no evidence to support the extraction of the deciduous maxillary canine to facilitate the eruption of the palatally ectopic maxillary permanent canine. Two randomised controlled trials were identified but unfortunately, due to deficiencies in reporting, they cannot be included in the review at the present time.