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 Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 17  |  Issue : 3  |  Page : 563-567

Comparison of efficacy of local anesthetic drugs lignocaine, ropivacaine, and bupivacaine in pain control during extraction of mandibular posterior teeth


Private Practitioner, New Delhi, India

Date of Submission28-Mar-2020
Date of Decision04-Jul-2022
Date of Acceptance24-Aug-2022
Date of Web Publication2-Nov-2022

Correspondence Address:
Dr. Preeti Gupta
Private Practitioner, New Delhi
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jdmimsu.jdmimsu_78_20

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  Abstract 


Background: Posterior tooth extractions provide a challenge due to variations in anesthetic capacity and effects, especially postoperatively. The aim of the study was to compare the efficacy of three anesthetic agents – lignocaine, bupivacaine, and ropivacaine – during extraction procedure of mandibular posterior teeth. Materials and Methods: Two hundred and fifty study participants were randomly divided into three groups: Group I – individuals under 2% lignocaine (n = 84), Group 2 – individuals under bupivacaine (n = 86), and Group 3 – individuals under ropivacaine (n = 80). Hemodynamic and anesthetic and analgesic parameters were recorded and statistically analyzed using analysis of variance. Results: Significant differences were observed between three anesthetic agents used pertaining to anesthetic and analgesic changes, whereas no significant effects were observed when comparing the hemodynamic parameters. Conclusion: Ropivacaine provided the best clinical outcome in terms of both anesthetic efficacy and postoperative analgesia following the extraction of mandibular posterior teeth.

Keywords: Analgesia, anesthesia, bupivacaine, intraoperative, lignocaine, postoperative, ropivacaine


How to cite this article:
Gupta P. Comparison of efficacy of local anesthetic drugs lignocaine, ropivacaine, and bupivacaine in pain control during extraction of mandibular posterior teeth. J Datta Meghe Inst Med Sci Univ 2022;17:563-7

How to cite this URL:
Gupta P. Comparison of efficacy of local anesthetic drugs lignocaine, ropivacaine, and bupivacaine in pain control during extraction of mandibular posterior teeth. J Datta Meghe Inst Med Sci Univ [serial online] 2022 [cited 2023 Feb 4];17:563-7. Available from: http://www.journaldmims.com/text.asp?2022/17/3/563/360235




  Introduction Top


Local anesthetic agents are used for obtaining anesthetic and analgesic activity during surgery and management of pain. These agents are classified into two categories: (a) amides and (b) esters. The amide group contains lignocaine, mepivacaine, bupivacaine, levobupivacaine, prilocaine, and ropivacaine, whereas the ester group contains procaine, chloroprocaine, amethocaine, and cocaine. Injectable local anesthetic agents get absorbed and undergo distribution to distant organs. Most of the absorbed local anesthetic drugs undergo hepatic clearance. These agents are tightly bound to plasma proteins, thus limiting the bioavailability. Lignocaine is moderately bound to proteins and has a high percentage of hepatic extraction (70%–75% per passage), whereas bupivacaine and ropivacaine are extremely bound to proteins and get <50% clearance per passage. Ropivacaine is a long-acting amide local anesthetic agent with an efficacy similar to that of bupivacaine. It has low central nervous and cardiac toxicity potential and low propensity for motor nerve block. This drug has low cardiotoxicity as compared to bupivacaine but equivalent to lignocaine.[1]

Lignocaine was first synthesized by Nils Lofgren (1948), whereas bupivacaine was first of all synthesized by A. F. Ekenstam (1957). Its action lasts for two-to-three times more than that of lignocaine with much prolonged analgesic effect even after return of sensation. Both these agents are used for attaining infiltration and surface anesthesia and field or conduction block. This study showed a reduction in heart rate between 15 and 30 min for both agents. Bupivacaine was found to be more effective in maintaining analgesics at 8-h period.[2] The amidoamine local anesthetic agents exhibit their action by binding to specific receptors, located on sodium channels located in nerves, thus, blocking ionic movements through these channels. Studies have reported that a single injection of 1% lignocaine can induce chondrotoxicity in addition to toxic effects on corneal endothelial cells, rotator cuff tenofibroblasts, human tumor cells, melanoma cell lines, and mesenchymal stem cells. Ropivacaine, on the other hand, has been demonstrated to exhibit decreased neuro- and cardiotoxicity; inhibition of platelet aggregation, and antibacterial action.[3]

Surgical extraction of posterior teeth, especially third molars, involves a certain level of difficulty. Peripheral neural sensitization is considered to be a major after-effect following surgical extractions.[4]

The aim of this study was to compare the esthetic and analgesic efficacy of lignocaine, ropivacaine, and bupivacaine in posterior tooth extractions.


  Materials and Methods Top


This study was conducted on 250 individuals (average age ± standard deviation = 22.9 ± 2.1 years) indicated for posterior tooth extractions. The study participants were randomly divided into three groups:

  1. Group 1: Individuals undergoing extractions under 2% lignocaine (n = 84)
  2. Group 2: Individuals undergoing extractions under bupivacaine (n = 86)
  3. Group 3: Individuals undergoing extractions under ropivacaine (n = 80).


This was a single-blind study when the surgeon was given an anesthetic cartridge without group identification. All anesthetic and surgical procedures were performed by a single operator. Data regarding vital signs such as pulse rate, blood pressure, pain during procedure, postoperative pain duration, and analgesic effects were monitored. Vital signs were monitored as per Meechan's protocol:[5]

  1. Immediately before anesthetic administration
  2. Five minutes following anesthetic administration
  3. Ten minutes following anesthetic administration
  4. Fifteen minutes following anesthetic administration
  5. Twenty minutes following anesthetic administration
  6. Twenty five minutes following anesthetic administration.


The anesthetic potency during surgical procedure was measured using Sisk (1986) criteria: (1) successful: no pain during procedure; (2) successful: pain during extraction but reinjection not required after initiating the procedure; (3) successful: here, there was pain during procedure, but no pain was present after the second injection; (4) limited success: pain after two injections but completion of surgery without third; (5) limited success: pain beginning after two injections but completion of procedure; (6) failure: pain beginning after first, again after second, third injection required; (7) failure: pain beginning after two injections, third injection required; and (8) failure: no anesthesia after two injections, third injection required or suspension of treatment.

The intensity of intraoperative pain was assessed by individuals themselves using the Visual Analog Scale (VAS) as proposed by Briggs and Closs (1999) ranging from 0 (no pain) to 100 (worst pain). This scale was also employed for testing analgesic effect of tested local anesthetic.

Sample size calculation

The sample size was calculated using an estimated medium effect size – partial ƞ2 = 0.06, α error of 0.05, and 95% power of the study. Type I error was found at 0.05.

The statistical tool employed was analysis of variance for intergroup comparisons. P < 0.05 was considered statistically significant, whereas <0.001 was considered to be extremely significant.


  Results Top


On comparing anesthetic and postoperative analgesic effects following administration, a significant difference was noted in onset (P < 0.01), and lignocaine demonstrated the least onset of anesthesia. Extremely significant differences were observed between duration of anesthetic activity, intensity difference postoperatively, time of first felt pain and after 6 h, time of consuming first analgesic, and number of analgesics consumed postoperatively [Table 1] and [Graph 1].
Table 1: Parameters related to anesthetic and postoperative analgesic action

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Hemodynamic disorders observed were constant and demonstrated no significant side effects. Following injection of 2% lignocaine in the first 5 min, an increase in both systolic and diastolic blood pressures was seen, which was followed by a reduction in systolic pressure after 5 min, and a decrease in diastolic pressure after 10 min was seen. While on bupivacaine administration, a slight drop in systolic pressure was observed within the first 5 min which then increased slightly. Furthermore, a slight elevation in diastolic blood pressure was seen in the first 5 min or 10 min. Similar changes were observed with ropivacaine administration as well. However, these changes were nonsignificant [Table 2].
Table 2: Demonstrating vital parameters observed during procedures

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  Discussion Top


According to Malamed, local/regional anesthesia is defined as “regional lack of sensation to painful stimulus along with temperature, pressure, touch, etc., due to reversible peripheral nerve conduction loss along specified pathways.”[6] A local anesthetic molecule is composed of two polar ends: (a) hydrophilic secondary or tertiary amino group and (b) lipophilic aromatic ring. Depending on the type of intermediate alkyl linkage between both the poles, these agents are classified into ester or amide anesthetic.[6]

The choice of anesthetic agent is based on three factors: (a) potency, (b) time taken for onset, and (c) duration of anesthesia.[7] Tijanic and Buric in their study on comparisons between anesthetic potentials of bupivacaine and ropivacaine measured: (a) quality of anesthesia, (b) success rate, (c) time of onset, (d) duration, (e) intensity of intraoperative pain, (f) blood pressure, and (g) pulse rate. Administration of 0.75% ropivacaine demonstrated successful anesthesia among 96.6% of the study participants. Statistical significance for all criteria was obtained for 0.75% ropivacaine. The duration of anesthesia for ropivacaine and bupivacaine was 412.17 ± 110.04 and 376.30 ± 98.51 min, respectively. The onset time was 151.50 ± 80.93 and 168 ± 79.73, respectively. The success rates were 96.6% and 93.3%, respectively. Furthermore, a lower intraoperative pain was observed with ropivacaine.[8]

Anesthetic duration is proportional to the extent of binding to proteins, whereas the onset of anesthetic action is dependent on factors such as anesthetic technique and intrinsic drug substance.[9] Bupivacaine is a long-acting anesthetic agent with its duration of action extending between 7–11 h and 9 h for inferior alveolar nerve block and infiltration anesthesia, respectively.[10] It has demonstrated longer anesthesia of soft tissues and reduced postoperative pain along with late peak in pain (12 h) and lesser intensity on VAS. However, it has been reported to cause high diastolic and low systolic blood pressures though these are not statistically significant.[11] However, it has been reported to have a narrow safety margin due to its cardio- and neurotoxic side effects.[12]

Ropivacaine is also a long-acting amide local anesthetic possessing vasoconstrictive property inherent within.[13] It is a monohydrate of 1-propyl-2',6'-pipecoloxylidide hydrochloride and is a S-enantiomer.[14] Its anesthetic half-life is up to 4.2 h and is required in lesser concentrations of 0.5% and 0.75% as compared to lignocaine (2%).[13] The reason for introduction of S-enantiomeric form over the racemic form was the wider safety margin, the same amount of analgesia, and less postoperative motor block. Ropivacaine shows a selective action by acting on Aδ and C nerve fibers than on Aβ.

Dada O (2019) in their study involving various concentrations of ropivacaine (0.75%, 0.5%, 0.375%, and 0.25%) in inferior alveolar nerve block in third molar extractions demonstrated that the 0.5% and 0.75% concentrations were most effective in producing rapid onset and prolonged pain control.[15] Anesthetic effects were observed at 0.5% and 0.75% at 6.0 ± 0.4 and 5.6 ± 0.4 h, respectively, whereas the other diluted contents were found to have significantly shorter durations of soft-tissue anesthesia apart from repeated injections.[15]

Postoperative pain can rebound as hyperalgesia following a peripheral nerve block.[16] Local anesthetics demonstrate an anti-inflammatory effect by blocking leukotriene B4 release from polymorphonuclear leukocytes. Furthermore, histamine release is blocked along with other inflammatory mediators. Local anesthetic agents (millimolar concentrations) have also been shown to possess antimicrobial activities both in vivo and in vitro. This activity is primarily bactericidal rather than bacteriostatic. 2% lignocaine has been demonstrated to inhibit the growth of  Escherichia More Details coli, Streptococcus pneumoniae, and Pseudomonas aeruginosa.[17],[18] Furthermore, Kaewjiaranai T et al. have shown a temperature- and concentration-dependent bactericidal activity exhibited by bupivacaine specifically against Staphylococcus epidermidis and E. coli.[19] While injecting local anesthetic agents, normal oral microflora can pass into tissues. These microbes are capable of causing suppurative infections or bacteremia. Thus, the bactericidal effect of these anesthetic agents can help suppress these infections.[20]

Badr N did a comparative analysis on analgesic effect of 0.25% and 0.5% bupivacaine concentrations in individuals with third molar extractions. Pain intensity was observed at 2-h and 24-h intervals. It was found that 0.5% bupivacaine had a better analgesic effect when compared to 0.25% concentrations.[21]

Mandibular block anesthesia can be difficult to achieve in certain individuals; hence, it shows variations in response among different individuals.[22] Adelusi EA et al. studied 41 individuals who underwent bilateral maxillary extractions for orthodontic treatment using a split-mouth technique where 0.5% and 0.25% bupivacaine were injected. No significant difference was observed between onset, pain during extraction, and duration of anesthesia. Based on these observations, the use of 0.25% bupivacaine was advocated.[23]

It has been postulated that local anesthetics act by blocking of neuronal sodium channels and membrane expansion. These agents act by altering the structure of the lipid bilayer by the lipophilic part of the anesthetic molecule. This process is termed as “membrane expansion.” This constitutes 10% of anesthetic activity while the remainder 90% by caused by membrane stabilization or condition blockage which results in a decrease in sodium conductance and depolarization.[24] These agents act by reversible blocking of nerve conduction distal to the site of injection.[25] Blocking of sodium channels impairs the generation of action potentials which are required for pain propagation. Thus, this block can result in motor and sensory nerve blockage.[26]

Ropivacaine has a half-life of 41 min after administration through intravenous route and a 94% plasma protein binding.[24] Ropivacaine has been to have a much safer anesthetic profile for medically complicated individuals as well.[27]

Bupivacaine has been reported to have a narrow safety margin due to its cardio- and neurotoxic side effects.[28] Furthermore, Mehta et al. demonstrated changes in cardiac activity by increase in QRS width caused by bupivacaine when compared to ropivacaine.[14] However, this agent has been demonstrated to produce extended anesthetic effect when tested using a liposomal delivery system for local infiltration in various surgical sites.[29]

Mishra et al. confirmed in their split-mouth study in periodontal surgeries a comparable efficacy of ropivacaine when compared with lignocaine with additional advantages of longer duration, better postoperative pain control, and reduced loss of blood during the procedure.[30] Furthermore, ropivacaine has shown comparable pharmacodynamic and kinetic properties to bupivacaine with lesser toxicity.[31]

Both bupivacaine and ropivacaine have been shown to demonstrate prolonged analgesia for 10.3 and 9.6 h, respectively, after third molar surgeries.[32] Brkovic et al. in their study have demonstrated a similar intensity of anesthesia using either ropivacaine and bupivacaine after employing the VAS and Verbal Rating Scale.[33]

Short-acting local anesthetics show faster time of onset and faster titrability. It also has additional advantages such as (1) less costlier; (2) easier monitoring, and (3) larger safety margin than long-acting anesthetic agents.[34] An effective peri- and postoperative pain management significantly affects patient morbidity.[35]


  Conclusion Top


This study demonstrated that ropivacaine, a long-acting amide anesthetic, provides better intraoperative and postoperative pain control during extractions of posterior mandibular teeth.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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