Third molar eruption patterns and mandibular dental arch crowding

Abstract

Longitudinal cephalometric and study cast records were analysed for a sample of non-orthodontically treated Caucasians (31 male, 23 female) at two stages of mandibular dental arch development. Stage 1 represented earliest completion of the secondary dentition, with the exception of the mandibular third molars. Stage 2 was approximately 5 years later and was decided on the basis of emergence or, if impacted, at least three quarters root development of the third molars. Parameters at Stage 1 and Stage 2 and the changes between those stages were compared for 3 groups, subdivided for sex and status of third molar development — complete or partial eruption (Group 1), mesioangular impaction (Group 2) and absence (Group 3) of both mandibular third molars.

Keywords

• third molars
• eruption patterns
• crowding