The effect of pre-anesthesia with a needle-free system versus topical anesthesia on injection pain of the inferior alveolar nerve block: a randomized clinical trial

Local anesthetic delivery systems for the management of postoperative pain

Postoperative pain (POP) is a major clinical challenge. Local anesthetics (LAs), including amide-type LAs, ester-type LAs, and other potential ion-channel blockers, are emerging as drugs for POP management because of their effectiveness and affordability. However, LAs typically exhibit short durations of action and prolonging the duration by increasing their dosage or concentration may increase the risk of motor block or systemic local anesthetic toxicity. In addition, techniques using LAs, such as intrathecal infusion, require professional operation and are prone to catheter displacement, dislodgement, infection, and nerve damage. With the development of materials science and nanotechnology, various LAs delivery systems have been developed to compensate for these disadvantages. Numerous delivery systems have been designed to continuously release a safe dose in a single administration to ensure minimal systemic toxicity and prolong pain relief. LAs delivery systems can also be designed to control the duration and intensity of analgesia according to changes in the external trigger conditions, achieve on-demand analgesia, and significantly improve pain relief and patient satisfaction. In this review, we summarize POP pathways, animal models and methods for POP testing, and highlight LAs delivery systems for POP management. STATEMENT OF SIGNIFICANCE: Postoperative pain (POP) is a major clinical challenge. Local anesthetics (LAs) are emerging as drugs for POP management because of their effectiveness and affordability. However, they exhibit short durations and toxicity. Various LAs delivery systems have been developed to compensate for these disadvantages. They have been designed to continuously release a safe dose in a single administration to ensure minimal toxicity and prolong pain relief. LAs delivery systems can also be designed to control the duration and intensity of analgesia to achieve on-demand analgesia, and significantly improve pain relief and patient satisfaction. In this paper, we summarize POP pathways, animal models, and methods for POP testing and highlight LAs delivery systems for POP management.

Interventions to Reduce Intra-Operative and Post-Operative Pain Associated with Routine Dental Procedures in Children: A Systematic Review and Meta-Analysis

OBJECTIVE

implementing appropriate pharmacological and non-pharmacological interventions to alleviate pain related to routine dental procedures in paediatric patients could enhance children's ability to manage dental care. The aim of this review was to investigate the effectiveness of and provide recommendations for interventions that can be used to reduce intra-operative and post-operative pain associated with routine paediatric dental procedures.

METHODS

A systematic review of randomised controlled clinical trials (RCT) was conducted. Multiple electronic databases were systematically searched. The Cochrane risk-of-bias tool for RCTs was used to evaluate the quality of the included studies. A meta-analysis was performed to determine the effectiveness of the interventions using the Cohen's d standardised mean differences (SMD) and 95% confidence intervals (CIs) for continuous outcomes. The GRADE tool was used to assess the certainty of evidence to make recommendations.

RESULTS

The review included forty-five RCTs comprising 3093 children. Thirty-seven RCTs were included in the meta-analysis, which showed the effectiveness of behavioural interventions (SMD = -0.50, 95% CI -0.83 to -0.18), mechanoreceptor and thermal receptor stimulation (SMD = -1.38, 95% CI -2.02 to -0.73) for intra-operative pain, and pre-emptive oral analgesics (SMD = -0.77, 95% CI -1.21 to -0.33) for reducing post-operative pain in children receiving routine dental care.

CONCLUSION

The GRADE results for these interventions were strong recommendation (IB) for their use, based on moderate evidence and their benefits far outweighing the harm, and they can be delivered readily with minimal training to reduce the pain experience of paediatric patients.

Comparative Evaluation of the Anesthetic Efficacy of Needle-Free Anesthesia and Conventional Anesthesia in Patients With Symptomatic Irreversible Pulpitis: A Randomized Clinical Trial

Introduction Pain is the primary reason for which most of the patients seek endodontic treatment. Local anesthesia is considered to be the most important step in the procedure to reduce the pain. However, the majority of the patients do not cooperate due to the fear of syringe anesthesia. The aim of this clinical trial was to compare the anesthetic efficacy of needle-free anesthesia and conventional anesthesia in patients with symptomatic irreversible pulpitis undergoing root canal therapy. Materials and methods A total of 54 patients were enrolled in the study, and the treatment was administered by a single operator. The initial assessment of vitality included cold testing, heat testing, and electric pulp testing. Preoperative pain was assessed using the Visual Analog Scale (VAS) before the administration of anesthesia. Local anesthesia was administered according to the group assigned: Group 1 (conventional anesthesia) and Group 2 (needle-free anesthesia). The pain was assessed during the administration of anesthesia. Following the administration of anesthesia, the vitality of the tooth was evaluated using cold testing, heat testing, and electric pulp testing. Subsequently, the tooth was isolated with a rubber dam, and the access cavity was prepared. The pain was assessed during access cavity preparation and during the first file insertion. Working length was determined using an apex locator (Root ZX Mini, J Morita, Saitama, Japan) and was confirmed using intraoral periapical radiographs. Later on, further treatment was carried out. Results A total of 54 participants were included in this clinical trial. There was no significant difference in mean age distribution between the two groups (p=0.852). Considering the frequency distribution of gender, there was no significant difference; however, Group 1 had more female participants (59.3%) compared to Group 2 (33.3%). There was a significant reduction in the mean pain score in Group 2 compared to Group 1 during the delivery of anesthetic agents (p=0.000). Conclusion Needle-free anesthesia proves to be equally effective as the conventional syringe system in patients experiencing symptomatic irreversible pulpitis undergoing root canal treatment. However, it is noteworthy that patients exhibited greater comfort levels with needle-free anesthesia systems specifically during the administration of the anesthetic solution.

Effect of a needle-free system versus traditional anesthesia on pain perception during palatal injections in children

BACKGROUND

Needle-free injection systems can contribute to the prevention of needle-related pain during palatal infiltration anesthesia (PIA) in children. Research on this topic in children is required.

AIM

The purpose of this clinical study was to evaluate the effectiveness and patient preference of a needle-free system versus traditional anesthesia (TA) on pain perception during PIA in children.

DESIGN

The study was designed as a randomized, controlled crossover clinical study with 48 children aged 6-12 years requiring dental treatment with PIA in bilateral maxillary primary molars. TA was applied on one side and the Comfort-in™ injection system (CIS) on the other side in two separate sessions. Then, patient preference was recorded. The pain perception during PIA was evaluated using the Wong-Baker FACES Pain Rating Scale (PRS) and the Face, Legs, Activity, Cry, Consolability (FLACC) Scale. The data were analyzed for statistical significance (p < .05).

RESULTS

There were statistically significant differences between the TA and the CIS according to the PRS and FLACC Scale scores. On both scales, significantly higher pain ratings were observed in the TA group during PIA (p < .001). There was a statistically significant difference in terms of patient preference (p < .001). Although 77.1% (n = 37) of the children preferred the CIS, 22.9% (n = 11) preferred the TA. Moreover, patient preference for the CIS was significantly higher in older children (p < .01).

CONCLUSIONS

The application of a needle-free system during PIA ensured a decrease in pain perception in children.

Effect of the new needle-free injection system on pain perception and dental anxiety during anesthesia: randomized controlled split-mouth study

Backgrounds

Pain management is one of the most important factors affecting the success of pediatric dentistry. Therefore, new needle- and pain-free local anesthesia techniques have been developed in parallel with technological advancements. The purpose of this study is to compare the pain perception and dental anxiety levels associated with a needle-free injection system (Comfort-in™) and the classic needle method during treatment-required infiltration anesthesia in children.

Methods

This randomized controlled crossover split-mouth clinical study included 94 children who required dental treatment with local anesthesia using a dental needle or needle-free injection system for the bilateral primary molars. The Wong-Baker Scale (WBS) was used to measure pain perception at different times, and the Modified Child Dental Anxiety Scale (MCDAS) was used to measure the anxiety level of the child. A statistical software package was used to process the data. Statistical significance was set at P < 0.05.

Results

There was no significant difference between the needle-free injection system and dental needle method during the induction stage for filling and pulpotomy (P > 0.05). "Pain on postoperative 1st day" was similar in both types of anesthesia (P = 0.750).

Conclusions

The needle-free injection system was as effective as the dental needle method. The Comfort-in™ system was an acceptable alternative for patients during the postoperative period. Understanding how pain management may be provided during local anesthesia administration and a child's fear and anxiety regarding the dentist may lead to better dental compliance.

Comparative evaluation of pain perception with a new needle-free system and dental needle method in children: a randomized clinical trial

Background

Pain control during dental procedures is one of the most important topics related to behavior management in children. This study aims to compare the pain perception associated with a needle-free system (Comfort-In™) and the dental needle method during filling and pulpotomy treatments in children.

Methods

The study included teeth that required treatment (pulpotomy or filling treatment) in 56 patients aged 4 to 11 years with no systemic problems or history of allergy. Patients were randomly divided into the needle-free system group (filling treatment, n = 13; pulpotomy, n = 15) and dental needle method group (filling treatment, n = 14; pulpotomy, n = 14). For pulpotomy and filling treatment performed with 0.3 mL anesthesia, the active ingredient of which is 2% lidocaine and 1/80000 epinephrine. The patients’ behavior before the procedure was evaluated by a pediatric dentist using the Frankl Behavior Scale. The pain intensity was assessed Immediately after injection (induction), during treatment (treatment), and at the end of the treatment (post treatment) by the Wong-Baker Faces Pain Scale.

Results

The median (IQR-InterQuartile Range) induction pain value was 6[3-8] and 2[0-4] in dental needle method and needle-free system respectively, p < 0.001). In filling and pulpotomy treatment group, no difference between the needle and needle-free group for treatment and post-treatment pain values.

Conclusions

For pulpotomy and filling treatment, needle-free system performed with 0.3 mL anesthesia was found as effective as infiltrative anesthesia with a dental needle method.

Trial registration

ClinicalTrials.gov, NCT04653974. Registered 4 December 2020 – Retrospectively registered.