title: Efficacy of mandibular topical anesthesia varies with the site of administration.
abstract: This study compared the threshold of pain sensitivity in the anterior mandibular mucobuccal fold with the posterior. This was followed by a comparison of the reduction of needle insertion pain in the anterior mucobuccal fold and the pterygo-temporal depression by either topical anesthesia or nitrous oxide inhalation. The pain threshold was determined by an analgometer, a pain-measuring device that depends on pressure readings; additionally, pain caused by a needle inserted by a normal technique was assessed using a visual analog scale (VAS). The threshold of pain was significantly lower in the incisor and canine regions than in the premolar and the molar regions (P < 0.001). Compared to a placebo, topical anesthesia significantly reduced the pain from needle insertion in the mucobuccal fold adjacent to the mandibular canine (P < 0.001), but did not significantly reduce pain in the pterygotemporal depression. The addition of 30% nitrous oxide did not significantly alter pain reduction compared to a control of 100% oxygen. These results suggest that topical anesthesia application may be effective in reducing the pain of needle insertion in the anterior mandibular mucobuccal fold, but may not be as effective for a standard inferior alveolar nerve block. The addition of 30% nitrous oxide did not lead to a significant improvement.
mesh_terms: D000328:Adult; D000539:Alveolar Process / Q000502:physiology; D000704:Analysis of Variance; D000766:Anesthesia, Dental / Q000379:methods*; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001566:Benzocaine / Q000008:administration & dosage; D005157:Facial Pain / Q000209:etiology; D005260:Female; D006801:Humans; D007267:Injections / Q000009:adverse effects / Q000523:psychology; D008297:Male; D008334:Mandible / Q000033:anatomy & histology; D008340:Mandibular Nerve; D009339:Needles / Q000009:adverse effects; D009407:Nerve Block / Q000379:methods*; D009609:Nitrous Oxide / Q000008:administration & dosage; D010147:Pain Measurement; D017288:Pain Threshold; D018709:Statistics, Nonparametric