In the present study, two types of anesthetic solutions were used during extraction of the mandibular second primary molars, the first was alexadricaine 4% and the second was Mepecaine-L 2%, using infiltration technique. The efficiency of each of them to control pain during extraction was assessed by subjective and objective pain measuring scales. At the same time the change in pulse rate that occurred as a result of pain of the extraction was measured and compared with the pulse rate before extraction.
Articaine 4% was used in comparison with mepivacaine 2%, because the latter is one of the most commonly used anesthetic solutions, and the most commonly available for many years in the Egyptian dental market. Articaine was recently launched, and it attracted the attention for being a highly efficient and potent anesthetic agent (Gazal et al.2015; Martin et al. 2021).
The inclusion criteria of the participants included lower second primary molars indicated for extraction due to root caries, because in such cases the tooth was beyond possible repair and indicated for extraction. While cases with marked bone or root resorption were excluded because this factor would decrease the bone resistance and facilitate the extraction, and that would be a variable factor that can’t be standardized in all patients as the amount of bone and root resorption differs from case to another (Harokopakis-Hajishengallis 2007; Abdellatif 2011).
Patients included in the current study didn’t have previous experience at the dental clinic, and that was their first dental visit, to ensure that they didn't have negative previous experience that can affect their attitude and cooperation during extraction. Their age ranged from 6 to 8 years, because that age was the most suitable for communication with the children and explanation of the Wong–Baker Facial Pain Scale (WBFPS) because younger children won’t be able to judge the degree of their pain and categorize it on the pain scale. At the same time, alexadricaine is not recommended for children younger than 4 years (Katyal 2010; Malamed et al. 2000; Smith et al. 2014).
Anesthesia administration using infiltration techniques has many advantages, among these advantages being less painful and less invasive when compared to the nerve block technique. Different complications that can occur with nerve block technique are less common to occur with infiltration technique, like hematoma, muscle spasm and nerve injury. All these advantages make the infiltration technique the best choice to be used to provide dental treatment for pediatric patients (Awad and Mourad 2020; Kaufman et al. 2005; Peedikayil and Vijayan 2013).
The key for successful dental treatment for a child patient is control of pain, which in turn reduces stress and anxiety. Assessment of pain can be performed through 3 main tools, observation of behavior, self-reporting, and physiologic measurement. In the current study, 3 different parameters for assessment of pain were used following the 3 pain assessment tools.
WBFPS is a self-reporting scale, so that the child can express his/her feeling or degree of pain in a simple and easy way through choosing one of the 6 faces (Tomlinson et al. 2010).
The SEM scale is an observational assessment tool, used for assessment of the body reaction of the child in response to pain and clarifies the relationship between the pain and its effect on the eyes, sound produced by the child and body movement (Lathwal et al. 2015).
The third method used for assessment of pain and stress the patient is facing during dental treatment is measuring the physiological parameters as the pulse rate, it is an indirect assessment tool and not subjected to bias. Increase in the pulse rate or blood pressure is an alert that the patient is facing a stressful or painful situation (Alemany-Martínez et al. 2008; Sancho-Puchades et al. 2012).
The 3 tools of pain assessment were used in the current study with both groups for accurate assessment of pain.
Results showed that, there was a statistically significant increase in pulse rate after extraction in both groups, but the mean pulse rate after extraction was higher in the Mepecaine-L group than the alexadricaine. This can be attributed to better pain control by the alexadricaine, which is reflected upon the physiological parameters of the body. These results were in accordance with Bahrololoomi and Rezaei (2021) and Gazal (2015)
One of the methods used for assessment of pain was the Wong–Baker Facial Pain Scale, it is a self-reporting scale by the patient. Results showed that Alexadricaine showed statistically significantly lower pain score than Mepecaine-L, it was more potent and efficient than Mepecaine-L in control of pain during extraction of lower second primary molars. These results were in accordance with Azad et al. (2019), who found that articaine 2% was clinically more efficient than mepivacaine 2% in pain control. The marked efficacy of articaine in pain control can be attributed to its characteristic liposolubility due to its chemical structure and the presence of thiophene ring resulting in marked penetration ability, and superior pain control in comparison with mepivacaine 2%.
A contradicting result was reported by Odabaş et al. (2012), who stated that there was no significant difference between articaine 4% and mepivacaine 3% in pain control evaluated by WBFPS as well as there was no significant change in the heart rate or blood pressure readings taken during the whole session of treatment between both anesthetic solutions. These contradictions can be attributed to difference in the mean age of the patients as well as the difference in the concentration of the mepivacaine.
Regarding pain assessment using SEM scale, results showed that Alexadricaine showed statistically significantly lower Sound, Eye, Motor and total SEM scores than Mepecaine-L, which highlight the capability of alexadricaine to control intra-operative pain during extraction better than Mepecaine-L, these results agree with Gazal (2015) and Gao and Meng (2020) who found that Articaine proved to be more potent, with fast onset of action compared to the mepivacaine group.
This may be due to difference in the penetration ability of anesthetic agents through the soft tissue and cortical bone, which in turn affects the anesthetization of the lingual tissues, which is important during extraction of mandibular molars.