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Indications for extraction of third molars: a review of 1763 cases.

OBJECTIVE
Third molars have been described as different from other teeth in the oral cavity. They have the highest rate of developmental abnormalities and, most importantly, are last in the eruption sequence. We investigated reasons for third molar teeth extraction in patients attending the outpatient oral surgery clinic of the Lagos University Teaching Hospital, Nigeria.


MATERIALS AND METHODS
A retrospective review of patients who had third molar extractions between January 2001 and June 2006 was conducted. Data retrieved and analysed were: age and sex of patients, indication for extractions, type of teeth extracted, technique of extractions (surgical and non-surgical) and angulations of impaction in case of impacted lower third molars.


RESULTS
A total of 1763 patients (mean age +/-SD, 33.74+/- 13.3 years; range 15 - 92 years) had their third molars extracted during the period. Majority (58%) of them were females. Surgical extraction was carried out in 506 (28.7%) patients while 1257 (71.3%) patients had non-surgical extractions. Caries and its sequela (63.2%) was the major reason for teeth extraction followed by recurrent pericoronitis (26.3%) and periodontitis (9.2%). Only 11 (0.6%) cases were removed for prophylactic reason. Patients who had their teeth removed for caries were significantly younger than those for periodontitis (P=0.000) but older than those for pericoronitis (P=0.000).


CONCLUSIONS
Caries and periodontal diseases occurring in relatively older age group were the major reasons for non-surgical extraction of third molars while recurrent pericoronitis occurring in relatively younger age was the major reason for surgical extraction of impacted third molars. Prophylactic surgical extraction of third molars is not a common practice in our environment.