A Survey of Pain, Pressure, and Discomfort Induced by Commonly Used Oral Local Anesthesia Injections

Intraoral local anesthesia is essential for delivering dental care. However, it is often perceived by some patients as the most painful and in some instances as the only painful part of the treatment, leading in extreme cases to avoidance of dental care. The present study measured the variables of pain, pressure, and discomfort caused by 4 commonly used local anesthesia injections: local infiltration, mental nerve block, inferior alveolar nerve block, and periodontal ligament injections. Patients were asked to grade pain, discomfort, and pressure on a visual analog scale as associated with needle insertion, operator finger position in the mouth, and pressure at injection. The inferior alveolar injection was graded to be the most painful followed by periodontal ligament and then mental nerve block injections. The periodontal ligament injections yielded the highest pressure scores. The inferior alveolar block injection yielded significantly more discomfort than local infiltration and mental nerve block injections when comparing finger and needle position. Local infiltration in the anterior maxillary region yielded the highest needle insertion and finger position discomfort scores. The present study suggests that the dental operator should be aware of local anesthesia injection pain, pressure, and discomfort together with efficacy of technique.