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Prevalence of vertical root fracture as the reason for tooth extraction in dental clinics
Koichi Yoshino1, Koji Ito, Masahiko Kuroda
1Department of Epidemiology and Public Health, Tokyo Dental College, 2-9-18 Misaki-cho, Chiyoda-ku, Tokyo, 101-0061, Japan, ko-yoshi@d8.dion.ne.jp.
Objectives:
The aim of this study was to investigate the prevalence, by gender, of vertical root fracture (VRF) as the main reason for the extraction of permanent teeth in dental clinics in Tokyo.
Materials And Methods:
Participating dentists were requested to provide information about extractions of permanent teeth they had performed from 1 January 2013 to 30 June 2013. The main reasons for extraction were categorized as follows: VRF, caries (horizontal root fracture included), periodontal disease and others.
Results:
At a total of 24 clinics, 736 teeth were extracted from 626 patients during the 6-month period. A total of 233 teeth were extracted by VRF (31.7%), and 93.6% of these were endodontically treated teeth. Among non-vital extracted teeth, 82.1% (179/218) had cast posts or screw posts. The percentage of extraction due to VRF was 29.4% in males and 34.7% in females. In females, the percentage of extractions due to VRF (34.7%) was higher than for periodontal disease (28.1%). In males, the percentage of extractions due to VRF increased with age (p < 0.05). The tooth types with the highest percentage of extractions due to VRF were the upper canine (46.7%), lower second premolar (48.0%) and lower first molar (50.0%) in males and the upper first premolar (43.3%), upper second premolar (44.4%), lower second premolar (53.8%) and lower first molar (54.5%) in females.
Conclusions:
These results indicate that we need to pay more attention to maintaining vital teeth while being aware of the particular tooth types in which VRF most frequently occurs.
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