Commentary

The most widely used local anaesthesia (LA) solution in dentistry is lidocaine, a fact also observed in Paediatric Dentistry. When treating child patients, it is essential that the anaesthesia is effective, so the child does not experience pain either during or after the entire dental procedure. There is already evidence recommending the use of articaine versus lidocaine for pulpal anaesthesia1 when infiltrative anaesthesia is used, but also as an infiltration supplement during the treatment of mandibular molars with irreversible pulpitis.2 However, the literature lacks high quality evidence concerning which LA solution is more effective in dental treatment for children. The current review aims to assess the efficacy of lidocaine (2%) and articaine (4%), both with epinephrine as a vasoconstrictor, and to compare the outcomes, advantages and harms associated with their use in paediatric dentistry.

The data search was extensively conducted and only randomised control trials (RCTs) involving paediatric population and comparing patient outcomes were included. The primary outcome measure was pain reported, measured during and after the dental procedure, while the secondary outcome measures were adverse events, onset and duration of numbness, need for supplemental injection and vital signs with other physical parameters monitored. All outcomes evaluated were reported using a variety of instruments and the authors used the Hedge's standardised difference in means and corresponding 95% confidence interval to summarise all self-reported outcomes. However, the subjective nature of pain measurement and the methodological inconsistencies and differences in reporting the outcome measures might have resulted in increased heterogeneity of the studies.3 The risk of bias assessment was applied to both study methodology and outcome measure of all included studies. The quality assessment was conducted by two reviewers, independently, following the Cochrane guidelines for assessing risk of bias of RCTs.4 It resulted in only one from the six included studies to be considered as ‘low’ risk of bias, while three studies were at ‘high’ risk of bias.

This suggests that the evidence provided can be considered as low quality. Although no difference was found in self-reported pain during procedure between lidocaine and articaine, Egger's test showed likelihood of publication bias in self-reported pain during procedure (p=0.015). Even though this type of bias is less common in more recent studies,5 it is related to the impediments authors encounter when trying to publish negative results.6 Additionally, in one case in which the study reported the pain score after the injection, the result was categorised as pain score during the procedure, which could have resulted in an under- or overestimation of the effectiveness of the LA solution during the entire dental treatment. Moreover, the authors reported a significant difference in the pain post-procedure favouring the articaine, but this should also be interpreted with caution, as substantial heterogeneity was observed.3 As six studies cannot be considered adequate for subgroup analysis,4 this was not performed, so possible reasons for the heterogeneity were not able to be examined. The fact that various instruments were used in different studies to measure the pain also makes it difficult to carry out a meta-analysis. It calls for more rigorous methodologies including better standardisation of patient outcomes, as adequately addressed by the authors.