<p>The electrical stimulation to gingiva induced the jaw-opening reflex (JOR). The threshold for inducing JOR (TH) is significantly reduced by application of orthodontic force to the tooth of the stimulating region. The intraperitoneal administration of TRPV1 antagonist significantly inhibited orthodontic force-induced excitation of JOR. However, the existence of adverse side effects (e.g., hyperthermia) of general administration of TRPV1 antagonists provides the necessity to investigate improved strategies. In this study, TRPV1 (AMG9810) and or TRPA1 (A-967079) antagonists were topically applied to gingiva, and the orthodontic force-induced JOR excitation was investigated with other features (e.g., inflammatory cytokines, and rectal and gingival temperatures). TRP antagonist(s) were applied to cervical gingiva immediately after (D0) or one day after (D1) orthodontic force application, and JOR TH was examined on D1. TRP antagonists significantly and dose-dependently increased JOR TH next day, in both D0 and D1 when applied alone. Furthermore, cocktail application of TRPV1 and TRPA1 antagonists (4% each) showed a cooperative/synergistic analgesic effect in both D0 and D1. In D0, the cooperative analgesic effect was associated with a significant reduction of CINC-2 in periodontium (Western blotting assay). In addition, rectal or gingival temperatures did not alter across the experiment. Taken together, topical application of TRP antagonists cocktail may reduce clinical orthodontic pain via CINC-2 reduction without adverse side effects.</p>