Is There a Possible Association between Skeletal Face Types and Third Molar Impaction? A Retrospective Radiographic Study

Abstract

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 19–25 years) 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 was regarded as mesofacial. An angle of > 93° was regarded as brachyfacial and an angle of < 87° as 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 than 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.

The Frequency of Mandibular Third Molar Impaction in Different Types of Vertical Skeletal Faces

“…Conversely, according to Kaplan and Dierkes, there was no significant difference in mandibular lengthsof patients with erupted and impacted third molars. 24 Eroz et al and Capelli found in their studies that patients with dolichofacial facial growth pattern had shorter mandibular lengths, consistently supporting the hypothesisof greater chances of third molar impaction in patients with dolichofacial pattern (26,27). These findings are in consistence with results of this study which showed that among all erupted third molars, 50% belonged to brachyfacial group, 34.4% belonged to mesiofacial group and 15.6% belonged to dolichofacial group.…”

“…25 A long ramus with short mandibular length are thought to be indicative of the impaction of mandibular third molar. 26 Results of this study showed that majority (48.3%) of all completely impacted teeth belonged to patients with dolichofacial pattern. The short mandibular length which is considered second most important factor, predisposed to impaction of third molar.…”

Analysis of Factors Related to Distal Proximal Caries on the Distal Surface of the Mandibular Second Molar Induced by an Impacted Mandibular Third Molar

“…Informed consent was obtained from all participants. Inclusion criteria: 9,10 (1) age 17 and above; (2) good oral hygiene; (3) at least one molar dentition area was complete; (4) the panoramic radiographs were straightforward and fully showed the emergence state of the MTM on the study side and the position relationship between the MTM and the adjacent MSM.…”

Análisis de terceros molares y sus estructuras anatómicas adyacentes mediante CBCT: meta-análisis

“…Una investigación de Tassoker y Cols., mencionan la relación entre el biotipo facial y los 3MM que son dientes con alto índice de impactación, lo cual puede surgir debido a la falta de espacio retromolar por insuficiente crecimiento mandibular asociado al biotipo facial (braquifacial, mesofacial y dolicofacial) (Tassoker et al, 2019).…”