Interstitial tissue pressure associated with dental injections: a clinical study

• Published in: Quintessence international (Berlin, Germany : 1985) Vol. 37; no. 6; p. 469
• Main Authors: Hochman, Mark N, Friedman, Mark J, Williams, Wayne, Hochman, Claudia B
• Format: Journal Article
• Language: English
• Published: Germany 01-06-2006
• Subjects: Adult; Anesthesia, Dental - instrumentation; Anesthetics, Local - administration & dosage; Cheek; Drug Therapy, Computer-Assisted; Extracellular Fluid - physiology; Humans; Hydrostatic Pressure; Injections - instrumentation; Lidocaine - administration & dosage; Mandibular Nerve; Maxillary Nerve; Palate, Hard; Periodontal Ligament; Transducers, Pressure
• ISSN: 0033-6572

The purpose was to measure the interstitial fluid pressure generated from tissue resistance during administration of local anesthetic solution at 4 anatomic locations within the oral cavity and to determine whether differences in soft tissue density affect interstitial fluid pressure when anesthetic solution is administered at a fixed flow rate.
A computer-controlled local anesthetic delivery device (CompuFlo, Milestone Scientific) that records and stores pressure data during a subcutaneous injection was used. Subjects consisted of adult patients seeking routine dental care that required local anesthesia. A total of 200 injections were administered and fluid pressure readings recorded. Injections were divided into 4 groups of 50: group 1--intraligamentary injections (PDL); group 2--palatal injection, anterior middle superior alveolar nerve block; group 3--supraperiosteal buccal infiltrations, and group 4--inferior alveolar nerve blocks. For all injections 1 cartridge (1.8 mL) of lidocaine containing 1:100,000 concentration of epinephrine was administered at a fixed flow rate of 0.005 mL/sec.
One-way analysis of variance (ANOVA) revealed that the data were statistically significant (P < .001), with corresponding mean values as follows: group 1, 293.98 psi; group 2, 68.16 psi; group 3, 11.50 psi, and group 4, 9.76 psi (F-ratio of 2371.933). Groups 1 and 2 were different from all other groups; groups 3 and 4 were not statistically different from each other.
Interstitial resistance to fluid pressure can be measured during administration of 4 different local anesthetic injections used in dentistry. Based on fluid pressure and tissue resistance characteristics, a soft tissue density classification was defined.