A multi-centre retrospective study of mandibular fractures: do occlusal support and the mandibular third molar affect mandibular angle and condylar fractures?

Do the Presence of Mandibular Third Molar and the Occlusal Support Affect the Occurrence and the Mode of Mandibular Condylar Fractures?

“…This investigation revealed that mandibular third molar defects cause mandibular condylar head fractures more so than mandibular subcondylar fractures. This result is very interesting, as previous studies have shown that the risk of mandibular condylar fractures is high because of the absence of mandibular third molars [4][5][6][7][8][9][10] . On the contrary, a comparison of mandibular condylar head and neck fractures demonstrates that a loss of the mandibular third molar increases the risk of mandibular condylar head fractures.…”

“…Several clinical studies have shown that loss of the mandibular third molars greatly increases the risk of mandibular condylar fractures compared to mandibular angle fractures [4][5][6][7][8][9][10] . These studies suggest that mandibular angles without a third molar increase bone quantity and resistance to angle fractures 5,6) . Consequently, when mandibular third molars are absent, probably most of the force is transmitted to the condylar area.…”

“…Many studies have demonstrated that the presence of mandibular third molars increases the risk of mandibular fractures and decreases the risk of condylar fractures [4][5][6][7][8][9][10] . However, previous clinical studies show that mandibular condylar fractures are considered synonymous with mandibular condylar neck fractures and head fractures [5][6][7][8][9][10] . These studies are not a formal assessment of the causative factors, and thus, the relationship between the risk of fractures and the presence of mandibular third molars remain unknown.…”

Correlation of Impacted Mandibular Third Molar With Incidence of Ipsilateral Angle and Condylar Fractures in Mandibular Trauma

“…Various classifications are used for impacted mandibular third molars such as based on angulation of impacted third molars to long axis of second molars as mesioangular, distoangular, vertical and horizontal 11 , Pell & Gregory 12 classifications based on relation of impacted third molars with Ramus as class I with third molar completely anterior to Ramus, class II with third molar partially covered by Ramus and class III with third molar fully covered by Ramus & Pell & Gregory classification based on vertical relationship of impacted third molars with occlusal level of second molar as class A with third molar at same occlusal level as that of second molar, class B with third molar below occlusal level of second molar but above the alveolar ridge and class C with third molar within the alveolar ridge 12 . In case of mandibular trauma, forces of tension are generated at the superior border of mandibular angle area and compression forces are generated at the lower border.…”

“…In case of mandibular trauma, forces of tension are generated at the superior border of mandibular angle area and compression forces are generated at the lower border. These forces of tension coupled with loss of the cortical strength by presence of mandibular impacted third molars decrease the strength of mandible at angle area by decreasing the amount of bone especially at the superior border, making this area susceptible to getting fractured and indirectly sparing mandibular condyle from getting fractured 12 . Superior positioning of impacted third molars like class A & B is supposed to make mandibular angle area particularly more susceptible to fractures as reported in various researches in literature 13 .…”