The Effects of Inflammatory Tooth Pain on Anxiety in Adult Male Rats

Introduction: This study aimed to examine the effects of induced inflammatory tooth pain on anxiety&nbsp;level in adult male rats. Methods: The mandibular incisors of 56 adult male rats were cut off and prefabricated crowns were&nbsp;fixed on the teeth. Formalin and capsaicin were injected intradentally to induce inflammatory tooth&nbsp;pain. Diazepam treated group received diazepam 30 minutes before intradental injection. The anxietyrelated&nbsp;behavior was evaluated with elevated plus maze test. Results: Intradental application of chemical noxious stimuli, capsaicin and formalin, significantly&nbsp;affected nociceptive behaviors (P<0.001). Capsaicin (P<0.001) and formalin (P<0.01) significantly&nbsp;increased the anxiety levels in rats by decrease in the duration of time spent in open arm and increase&nbsp;in the duration of time spent in closed arm. Rats that received capsaicin made fewer open arm entries&nbsp;compared to the control animals (P<0.05). Capsaicin (P<0.001) and formalin (P<0.01) treated rats&nbsp;showed more stretch attend postures compared to the control and sham operated animals. In diazepampretreated rats, capsaicin induced algesic effect was prevented (P<0.001). Conclusion: Inflammatory pulpal pain has anxiogenic effect on rats, whereas diazepam premedication&nbsp;showed both anxiolytic and pain reducing effects.