The Incidence of Intravascular Needle Entrance during Inferior Alveolar Nerve Block Injection

Background and aims. Dentists administer thousands of local anesthetic injections every day. Injection to a highly vascular area such as pterygomandibular space during an inferior alveolar nerve block has a high risk of intravascular needle entrance. Accidental intravascular injection of local anesthetic agent with vaso-constrictor may result in cardiovascular and central nervous system toxicity, as well as tachycardia and hy-pertension. There are reports that indicate aspiration is not performed in every injection. The aim of the pre-sent study was to assess the incidence of intravascular needle entrance in inferior alveolar nerve block injec-tions. Materials and methods. Three experienced oral and maxillofacial surgeons performed 359 inferior alveolar nerve block injections using direct or indirect techniques, and reported the results of aspiration. As-pirable syringes and 27 gauge long needles were used, and the method of aspiration was similar in all cases. Data were analyzed using t-test. Results. 15.3 % of inferior alveolar nerve block injections were aspiration positive. Intravascular needle entrance was seen in 14.2 % of cases using direct and 23.3 % of cases using indirect block injection tech-niques. Of all injections, 15.8 % were intravascular on the right side and 14.8 % were intravascular on the left