3D FEM comparison of lingual and labial orthodontics in en masse retraction.

Background: The aim of this study was to compare displacements and stress after en masse retraction of mandibular dentition with lingual and labial orthodontics using three-dimensional (3D) finite element models (FEM).

Methods: A 3D FEM of each lower tooth was constructed and located as appropriate to Roth's prescription. The 0.

Changes in the oral environment after placement of lingual and labial orthodontic appliances.

Background: This study compared the oral hygiene and caries risk of patients treated with labial and lingual orthodontic appliances throughout a prospective evaluation of the status of the oral environment before and after bracket placement.

Methods: A total of 20 orthodontic patients aged 19 to 23 years were included in the study and were divided into two groups: 10 patients wore Roth labial appliance (American Orthodontics, Sheboygan, WI, USA) and 10 patients wore STb lingual appliance (Ormco Corporation, Glendora, CA, USA). Plaque index (PI), gingival bleeding index (GBI), salivary flow rate, saliva buffer capacity, salivary pH, and Streptococcus mutans and Lactobacillus counts in saliva were determined at three time points: before orthodontic appliance placement (T0), 4 weeks after bonding (T1), and 8 weeks after bonding (T2).