Arthur Jeske DMD, PhD; James Zahrowski DMD, MS, PharmD
Articaine 4%, when compared to Lidocaine 2%, provides more effective local anesthesia in the first molar region for routine dental procedures while demonstrating a similar short-term adverse effect profile.
In patients requiring non-complex dental treatment, is articaine given as a local infiltration or nerve block, compared to lidocaine, an effective and safe local anesthetic?
This review utilized a search of 5 databases (Cochrane Central, Medline, Embase, ProQuest Health and Medical Complete) for publications of relevant trials between 1950 and 2009. The search included unpublished and ongoing studies using the metaRegister of controlled trials database, and a manufacturer of articaine and lidocaine was also contacted for relevant information. Language limitation eliminated 2 German citations. One author independently reviewed titles and abstracts using QUORUM criteria. Articles were utilized if they were RCTs in patients requiring non-complex, routine dental treatments and compared lidocaine 2% with 1:100,000 epinephrine and articaine 4% with 1:100,000 epinephrine. The four measured outcomes were anesthetic success, onset of action, post-injection adverse effects and/or post-injection pain. Data were combined and analyzed statistically for the four outcomes involving the first molar tooth. A random effects model was utilized, and the Cochran test for homogeneity and I2 test were used to evaluate heterogeneity and inconsistency among the studies.
This systematic review and meta-analysis of 9 RCTs including 1,725 subjects indicated the relative risk (RR) for achieving anesthetic success in the first molar for articaine versus lidocaine favored articaine (RR = 1.31, 95% CI 1.12-1.54, P = 0.0009) and the relative risk of adverse post-injection events between the two drugs was 1.05 (95% CI 0.66-1.65, P = 0.85). Articaine injection resulted in higher VAS pain scores after reversal of anesthesia, weight mean difference 6.49 (95% CI 0.02-12.96, p = 0.05), decreasing to 1.10 (95% CI 0.18-2.02, P=0.02) after 3 days. No significant heterogeneity was noted for any analyses, but subgroup analyses (based on age, gender, arch, or type of injection) and assessment of publication bias could not be done due to the small number of included studies.
The systematic review and meta-analysis indicated that articaine is more likely than lidocaine to achieve successful local anesthesia of the first molar for routine dental procedures, and both drugs appear to have similar post-injection adverse effect profiles. There are no data to support the use of articaine in children under the age of 4.
Source of Funding:
Importance and Context:
Lidocaine 2% with 1:100,000 epinephrine is commonly regarded as the standard local anesthetic for dental infiltrations and block injections, having been available in the U.S. over 50 years, and is the standard comparator local anesthetic in most studies evaluating other dental local anesthetics. Following the introduction of articaine 4% with 1:100,000 epinephrine in the U.S., various claims regarding its potential superiority for efficacy have not always been supported by RCTs, and its comparative potential for adverse events, including permanent nerve injury (e.g., paresthesia), required scientific validation. A systematic review is therefore warranted to clarify these issues
Strengths and Weaknesses of the Systematic Review:
Appropriate inclusion and exclusion criteria were utilized so that only randomized, controlled trials were included, and four databases were searched. However, only one author independently confirmed the appropriateness of included trials, so that there was no mechanism for adjudication of disagreements, and a language bias was acknowledged as a possible limitation of the review (two German-language RCTs were excluded and could have influenced the final result/trend from the 9 included studies). The defined time period for the search (1950 to 2009) was sufficiently broad to allow probable inclusion of all relevant reports, spanning the approximate time of introduction of both lidocaine and articaine to the U.S. marketplace. The meta-analysis was strengthened by a lack of significant heterogeneity
Strengths and Weaknesses of the Evidence:
Nine randomized controlled trials were included, all of which were prospective in nature. All studies utilized similar methods to assess primary outcome measures. Subgroup analyses could not be performed, which limits the applicability of the outcomes to larger groups of patients, and the author acknowledged a need for better management of allocation concealment, handling of losses and intention-to-treat analyses. A total of 525 subjects is too small a sample to assess adverse effects.
Implications for Dental Practice:
The now established efficacy of articaine 4% with 1:100,000 epinephrine for infiltration of lower posterior teeth, as well as its relatively more rapid metabolic clearance, are additional favorable features of this agent when compared to other dental local anesthetics, including lignocaine (lidocaine). At this time, it is not clear if these findings can be extrapolated to primary teeth or permanent teeth other than first molars or to the newer articaine 4% preparation, with a lower (1:200,000) epinephrine concentration. Conclusions of this systematic review agree with those from another recently published meta-analysis (1). Theoretical concerns regarding an increased incidence of nerve injury associated with 4% local anesthetic preparations remain, but are unlikely to be scientifically documented in randomized controlled trials due to the very large number of subjects needed for such studies.
1. Paxton K, Thome DE. Efficacy of articaine formulations: quantitative reviews. Dental Clinics of North America 2010;54:643-653.