Comparison of Efficacy of 4% Articaine versus Buffered 2% Lidocaine in Mandibular Third Molar Extraction: A Prospective Analytical Study

ABSTRACT

Background:

This prospective study was conducted to evaluate and compare the effectiveness of two local anaesthetic solutions: 4% articaine and buffered 2% lidocaine used during mandibular third molar extractions.

Materials and Methods:

A total of 200 extractions were performed at Sri Aurobindo College of Dentistry, equally divided into two groups.

Results and Conclusion:

Buffered Lidocaine was associated with reduced pain during injection and faster onset of subjective anaesthesia, whereas Articaine provided better pain control during the procedure. Both anaesthetics showed comparable durations and no postoperative complications, indicating both are safe and effective options when used appropriately.

INTRODUCTION

Mandibular third molar extraction is a routine yet complex dental procedure due to the dense mandibular bone and proximity to critical anatomical structures. Achieving profound local anaesthesia is essential, and two commonly used agents for this purpose are 4% Articaine and 2% Lidocaine. Articaine, introduced in 1976, is more lipid-soluble due to its thiophene ring, enhancing its ability to diffuse through bone. Lidocaine, developed earlier in 1948, is widely trusted but has a shorter duration of action. Buffering lidocaine with sodium bicarbonate improves pH, potentially reducing injection discomfort and accelerating onset.[1,2,3]

MATERIALS AND METHODS

The study included 200 patients aged 18–50, randomly assigned into:

• Group A: 4% Articaine with epinephrine (100 patients)

• Group B: Buffered 2% lidocaine with epinephrine (100 patients).

Buffered Lidocaine was prepared by removing 0.18 ml from the cartridge and replacing it with 0.18 ml sodium bicarbonate. Patients with systemic issues, drug allergies, or other contraindications were excluded [Figure 1].

Figure 1.

Buffering of 2% lidocaine: (a) 0.18 ml 2% Lidocaine was discarded using an insulin syringe (b) 0.18 ml sodium bicarbonate was withdrawn (c) 0.18 ml sodium bicarbonate mixed with the remaining lidocaine solution

Standard intraoral nerve block techniques were used for all patients. Pain during injection was assessed using the Sound Eye Motor Scale, and perioperative pain was measured using the Wong-Baker FACES scale. Onset time was determined by evaluating subjective and objective signs. The duration of anaesthesia was calculated from administration until the patient experienced postoperative pain.

Statistical analysis

Descriptive statistics were calculated as mean and standard deviation for quantitative variable, frequency and percentage for categorical variables. Pie or Bar diagrams are used for qualitative variables. The Pearson Chi-square test was used to justify the quantitative comparison of two different types of local anaesthesia (4% Articaine and Buffered 2% Lidocaine). If P value is less than 0.05, then it is considered as statistically significant result and if P value is more than 0.05, then it is statistically insignificant result.

RESULTS

Both groups had similar mean ages (Group A: 33.99 years; Group B: 32.93 years). Buffered Lidocaine caused significantly less pain during injection (mean standard error of mean score 1.12) compared with Articaine (2.28), P < 0.01. Onset Time: Subjective symptoms appeared faster with buffered Lidocaine (79.8 s) than with Articaine (88.8 s), P = 0.026. Objective symptoms were also faster with buffered Lidocaine (111.3 s vs. 116.7s), although this difference was not statistically significant (P = 0.118). Articaine offered better intraoperative pain control with more patients reporting zero pain (Wong-Baker Score 0). Both groups had similar durations of anaesthesia (Articaine: 183.8 min; Buffered Lidocaine: 187 min), showing no statistical significance (P = 0.483). There were no postoperative complications reported in either group [Figure 2].

Figure 2.

Comparison of various variables in Group A and Group B

DISCUSSION

Managing pain during third molar surgeries is vital for patient comfort. The physical discomfort from injecting local anaesthetics often stems from their acidic pH, especially when vasoconstrictors are added. Buffering local anaesthetics such as Lidocaine helps neutralize acidity, leading to faster diffusion and less pain.

Studies such as those by Kashyap et al., Bala et al., and Ramesh et al. agree with this study’s findings that buffered Lidocaine significantly reduces injection pain.[4,5,6] Although some researchers like Jain et al. observed no benefit from buffering, this study maintained consistent injection technique with a single operator to eliminate procedural bias, thus supporting the value of buffering.[7]

Onset time is influenced by a drug’s pKa value, lipid solubility, and local tissue conditions. Buffering reduces pKa, increasing the proportion of uncharged molecules that penetrate nerve membranes more efficiently. The current study aligns with previous findings by Kadambari et al. and Gorrela et al. that buffered Lidocaine leads to a quicker onset.[8,9]

In terms of pain control during the procedure, Articaine was more effective, likely due to its thiophene ring and ester group enhancing bone diffusion. Studies by Selvam et al. and Jain and John support these results, reporting better intraoperative analgesia with Articaine.[7,10]

Regarding anaesthesia duration, buffered Lidocaine nearly matched Articaine’s performance. This may be due to bicarbonate-induced CO₂ release, enhancing nerve penetration. These results echo findings from Bala et al. and Gorrela et al., although not all studies agree.[5,9]

Finally, safety is a critical concern. Although potential adverse effects of Articaine, Lidocaine, and sodium bicarbonate exist in the literature, no complications occurred in this study, reinforcing the safety of both agents when used correctly.

CONCLUSION

This study demonstrates that both 4% Articaine and buffered 2% Lidocaine are clinically effective and safe for mandibular third molar extractions. Articaine provides superior pain control during the procedure, while buffered Lidocaine ensures a more comfortable and quicker onset of anesthesia. Buffered Lidocaine is a cost-effective alternative but must be prepared freshly due to limited shelf life. More research is needed to enhance the shelf life of buffered solutions and further explore their clinical advantages.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.