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Prevalence of Mandibular Third Molars According to the Pell & Gregory and Winter Classifications
Karina Kendelhy Santos1, Frederico Santos Lages2, César Alexandre Barroso Maciel3
1Department of Dentistry, Federal University of Jequitinhonha and Mucuri Valleys. Diamantina, Rua da Glória, 187-Centro-Diamantina/MG-CEP, Minas Gerais, 39.100-000 Brazil.
Aim:
This study aimed to evaluate the prevalence of mandibular third molar positions according to the Pell & Gregory and Winter classifications, and to verify the association between the two classification methods.
Material And Methods:
This cross-sectional study was conducted at dental imaging clinic, from January to March 2019. The inclusion criteria were third molars with complete rhizogenesis and the presence of the mandibular second molar. Patients under 16 years were excluded. Digital orthopantomography (panoramic radiography) radiographs of the mandibular third molars were analyzed and observed according to both Pell & Gregory and the Winter classifications, in addition to verifying if they were impacted. Data were submitted to chi-square test.
Results:
and StatisticsIn total, 1087 teeth were analyzed, and 1055 teeth were included in the study. The teeth were most commonly found to be in the mesioangulated position (41.8%). Higher frequency was observed for position IIB (26.4%). The prevalence of impacted teeth was 79.6%. There was a statistically significant association between the Winter classification and Pell & Gregory classification (p < 0.001).
Conclusion:
It was concluded that 79.6% of the mandibular third molars were impacted. The most frequent classification of teeth was position IIB, and the mesioangulated position.
