Efficacy of Higher Gauged Needles or Topical Pre-Cooling for Pain Reduction during Local Anesthesia Injection: A Split-Mouth Randomized Trial

The effectiveness of cryotherapy and cooled topical anesthesia compared with conventional topical anesthesia in alleviating intraoral injection pain: A systematic review and meta-analysis

BACKGROUND

Injection pain remains a significant concern in dental procedures, often leading to patient anxiety and reluctance to seek necessary care.

AIM

This study aimed to assess the effectiveness of cryotherapy in reducing injection pain compared with topical anesthesia during intraoral local anesthesia.

DESIGN

MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL databases were searched up to November 2023. Inclusion criteria involved randomized clinical trials aligned with the PICO question. Study selection, data extraction, and risk of bias assessment using the ROB-2 tool were performed. The results were synthesized through a random-effects inverse variance meta-analysis. The primary outcomes assessed were the Visual Analogue Scale (VAS) and Sound Eye Motor (SEM). Subgroup analysis was conducted for children and adults.

RESULTS

In the meta-analysis, 31 RCTs involving 2470 subjects were included. Twenty-seven studies demonstrated cryotherapy's significant superiority over topical anesthesia in reducing injection pain via VAS in adults (p = .01), children (p = .01), and combined age groups (p < .001). Additionally, cryotherapy significantly outperformed topical anesthesia in reducing pain via SEM in children (p = .04) and combined age groups (p = .03) across 13 studies, with no significant difference in adults (p = .51). Furthermore, cooled topical anesthesia also outperformed room temperature topical anesthesia (p < .001). The certainty of the results, however, is of very low quality.

CONCLUSIONS

Our results indicate that cryotherapy significantly reduces injection pain compared with topical anesthesia, especially in children and combined age groups, but is less effective in adults. Additionally, cooled topical anesthesia is more effective than room temperature topical anesthesia. Thus, cryotherapy is a and potentially superior alternative to topical anesthesia, particularly for children.

Effect of Photobiomodulation Therapy with 915 nm Diode Laser on Pain Perception During Local Anesthesia of Maxillary Incisors: A Randomized Controlled Trial

This study aimed to evaluate the effect of photobiomodulation therapy (PBMT) with 915 nm wavelength on pain reduction during maxillary incisors' local infiltration in a randomized clinical trial study. A prospective triple-blinded split mouth clinical trial was designed to assess pain perception during needle insertion and local anesthetic injection in 32 healthy patients required operative caries management on contralateral maxillary incisors. After laser treatment (915nm, power of1.5 W, duty cycle of 60% and energy density of 72 J/cm² ) in active group and no irradiation in sham group, the injection was performed. Patients' perception of pain was immediately assessed using numerical rating scale (NRS) for pain. Washout period between two appointments was one week. Wilcoxon signed rank and Pearson correlation statistical analysis were used to assess for comparison of pain score between two appointments and the effect of anxiety level of previous dental injections. The mean scores of pain for the active laser and sham laser groups were 2.5±2.19 and 4.34± 2.52, respectively with a statistically significant higher NRS in the sham laser group (P˂0.05). In this study's condition, diode PBMT reduced pain during infiltration on maxillary incisors. Anxiety experience of dental injection had no significant effect on pain perception scale (P˃0.05).