Transient Pain Following Orthodontic Fixed Appliances Induces Sensitization Of Gingival And Periodontal Tissues

Introduction:Patients undergoing orthodontic therapy frequently experience varying degrees of discomfort and pain.Aims:The aim of this study was to evaluate the transient elffects of orthodontic treatment on the mechanical detection threshold(MDT)and mechanical pain threshold(MPT)of the buccal attached gingiva and the pressure pain threshold(PPT)of the buccal attached gingiva and teeth in two directions(vertical and parallel).Methods:Twenty patients(15 females and 5 males)aged 18 to 30 years old participated in the study.Perceived pain on a 0-10 cm visual analogue scale(VAS),MDT,MPT and PPT scores were evaluated at 2 time points:prior to orthodontic treatment(TO),24 hours after the first arch-wire placement(T1).Results:The pain intensity as assessed on the VAS was 4.211.8 cm.No significant changes in MDT or MPT were found at hand and buccal attached gingiva(P>0.05).The PPTs at the buccal attached gingiva of tooth 21,23,24,34;tooth 21,23,24,34 vertical and tooth 21,23 parallel were lower(more sensitive)at T1 than TO(P<0.01).Conclusions:These results suggest for the first time that pain following insertion of an arch-wire causes sensitization to blunt pressure stimuli both at the attached gingiva and in the periodontal ligament.Quantitative assessment of mechanical sensitivity may provide more insights into procedural-types of pain and allow to better monitor and evaluate effects of orthodontic treatment in the future.