Is There A Possible Association Between the Skeletal Face Types and Third Molar Impaction? A Retrospective Radiographic Study.

OBJECTIVE: Third molar impaction is seen much more than impaction of any other tooth as they are the last teeth to erupt. Inadequate retromolar space and the direction of eruption may be contributing factors. The aim of this study was to investigate the relationship between third molar impaction and different skeletal face types.

SUBJECTS AND METHODS: Panoramic and lateral cephalometric radiographs of 158 orthodontic patients (aged between 19 and 25 years old) were retrieved from the archived records of the Necmettin Erbakan University Faculty of Dentistry, Konya, Turkey. Third molar impaction was classified on the basis of Winter's classification. The skeletal facial type was determined by a measure of the angle created by the lines Ba-Na and Pt-Gn. The mean was 90 ± 2 and this value regarded as mesofacial. An angle of > 93 was regarded brachyfacial, and an angle of < 87 was regarded dolichofacial.

RESULTS: The overall presence of mandibular and maxillary third molar impactions was 65.2% and 38.6%, respectively. Although there was a statistically significant difference between different skeletal facial types and mandibular third molar impaction (p < 0.05), no statistically significant differences were observed between different skeletal facial types and maxillary third molar impaction (p > 0.05). Brachyfacials demonstrated a lower prevalence of third molar impaction as compared dolichofacials.

CONCLUSIONS: Different skeletal face types were associated with mandibular third molar impaction. Brachyfacials, who have a greater horizontal facial growth pattern than dolichofacials, showed a lower prevalence of impacted mandibular third molars.