title: Relief of palatal injection pain by liposome-encapsulated 2% lignocaine prepared by ultrasonic dental scaler.
abstract: Injections into the palate are common in dental treatment and are unpleasant for the patient. A liposomal encapsulation technique was developed to improve the efficacy of 2% lignocaine dental injection so that it could be used as a topical anaesthetic. Liposome-encapsulated 2% lignocaine was prepared as needed by sonicating 2% lignocaine hydrochloride dental injection (with 1:100,000 adrenaline) with a lipid mixture using a dental ultrasonic scaler for 1 min. The time to onset and time to take effect were calculated by a pinprick test in the palatal mucosa in 10 normal subjects. In another experiment, the preparation was tested in a further 22 subjects for its pain-relieving effect during a standard palatal injection, and compared with 18% benzocaine/2% tetracaine gel. The results showed that the mean (SD) time to onset and time to take effect of the liposome-encapsulated 2% lignocaine were 39.0 (21.4) and 157.5 (2.3)s, respectively, and the mean (SD) pain score measured on a visual analogue scale (VAS) during injection was 4.1 (2.3)cm. After the application of the gel the corresponding measurement was 4.8 (2.8)cm (p=0.045). The encapsulation of 2% lignocaine dental injection in liposomes by a dental ultrasonic scaler was effective in improving the efficacy of the anaesthetic for topical application.
authors.affiliation: Faculty of Dentistry, Khon Kaen University, 123 Mitraparp Rd., Muang District, Khon Kaen, 40002, Thailand. jarin@kku.ac.th
authors.forename: Jarin
authors.initials: J
authors.lastname: Paphangkorakit
authors.forename: Chaichan
authors.initials: C
authors.lastname: Sangsirinakagul
authors.forename: Aroonsri
authors.initials: A
authors.lastname: Priprem
mesh_terms: D000328:Adult; D000766:Anesthesia, Dental / Q000295:instrumentation / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001566:Benzocaine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007267:Injections / Q000009:adverse effects; D008012:Lidocaine / Q000008:administration & dosage*; D008081:Liposomes; D008297:Male; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement; D010159:Palate; D013748:Tetracaine / Q000008:administration & dosage*
chemical_list: D000779:Anesthetics, Local; D008081:Liposomes; D013748:Tetracaine; D008012:Lidocaine; D001566:Benzocaine