Hashimoto Shuichi, Yamashiro Mikiko, Fujita Kyohei, Yasuda Asako, Sunada Katsuhisa
Research Center for Odontology, Tokyo, Japan.
Department of Anesthesiology, The Nippon, Dental University, School of Life Dentistry at Tokyo, Tokyo, Japan.
J Endod. 2014 Sep;40(9):1370-4. doi: 10.1016/j.joen.2014.02.029. Epub 2014 Apr 16.
Epinephrine potentiates and prolongs the efficacy of local anesthetics by reducing blood flow. We investigated the effect of epinephrine on the pharmacokinetics of lidocaine and the pulpal blood volume after maxillary infiltration anesthesia in rats.
We measured the (14)C-radioactivity and (14)C-distribution in the maxilla and the dental pulp after the injection of 2% (14)C-lidocaine with or without 10 μg/mL epinephrine (n = 7) into the palatine mucosa proximal to the first molar. The blood volume in the pulp was measured using (99m)Tc-pertechnetate (n = 5).
When lidocaine was injected together with epinephrine, the lidocaine became widely distributed throughout the maxilla and was observed mainly in the first molar pulp. The lidocaine amount in the dental pulp at 10-60 minutes was more than 2 times higher than that after the injection of lidocaine alone. The relative pulpal blood volume after 20 minutes decreased to 63.1% of the value after the injection of lidocaine alone.
We found that lidocaine had infiltrated into the molar pulp after infiltration anesthesia. Furthermore, our results suggested that epinephrine augmented the retention of lidocaine in the pulp.
肾上腺素通过减少血流来增强并延长局部麻醉药的效果。我们研究了肾上腺素对上颌浸润麻醉后大鼠体内利多卡因药代动力学及牙髓血容量的影响。
将含或不含10μg/mL肾上腺素的2%（14）C-利多卡因注射到第一磨牙近端的腭黏膜后，我们测量了上颌骨和牙髓中的（14）C放射性及（14）C分布情况（n = 7）。使用（99m）Tc-高锝酸盐测量牙髓中的血容量（n = 5）。
利多卡因与肾上腺素一起注射时，利多卡因广泛分布于整个上颌骨，主要在第一磨牙牙髓中被观察到。在10 - 60分钟时，牙髓中的利多卡因量比单独注射利多卡因后高出2倍多。20分钟后的相对牙髓血容量降至单独注射利多卡因后值的63.1%。
我们发现浸润麻醉后利多卡因已渗入磨牙牙髓。此外，我们的结果表明肾上腺素增强了利多卡因在牙髓中的滞留。
