The aim of this study was to evaluate the prevalence of temporomandibular disorders (TMD) in individuals before and after orthodontic treatment. The sample comprised 200 individuals divided into four groups according to the type of malocclusion (class I or II) and the orthodontic treatment accomplished. An anamnestic questionnaire, comprising questions regarding the most frequent symptoms of TMD, was used to classify the sample according to the TMD presence and severity. A clinical examination, including TMJ and muscle palpation, mandibular range of motion, and joint noise analysis was performed. Based on the anamnestic questionnaire, 34% of the sample was considered as having mild TMD, whereas 3.5% had moderate TMD. A higher TMD prevalence was found in females. Joint noises (15.5%) followed by headache (13%) constituted the most frequent reported symptoms. The presence and severity of TMD have not shown any relationship with either the type of orthodontic mechanics or extraction protocols. On the other hand, a positive association was found between TMD and parafunctional habits and reported emotional tension. Orthodontic treatment is not associated with the presence of signs and symptoms of TMD.