Anesthetic Efficacy of Intranasal 3% Tetracaine plus 0.05% Oxymetazoline (Kovanaze) in Maxillary Teeth

Kovanaze Intranasal Spray vs Traditional Injected Anesthetics: a Study of Pulpal Blood Flow Utilizing Laser Doppler Flowmetry

OBJECTIVE

An ideal local anesthetic would be effective, minimally reduce pulpal blood flow (PBF), and not require injection. This study compared the effects of 3% tetracaine plus 0.05% oxymetazoline nasal spray (Kovanaze; KNS) and injections using 2% lidocaine with 1:100,000 epinephrine (LE) or 3% mepivacaine plain (MP) on PBF, anesthetic efficacy, and participant preference.

METHODS

In a double-blind cross-over design, 20 subjects randomly received a test anesthetic and placebo at each of 3 visits (KNS/mock infiltration; mock nasal spray/LE; or mock nasal spray/MP). Nasal sprays and infiltration apical to a maxillary central incisor were delivered ipsilaterally. PBF was evaluated by laser Doppler flowmetry, and local anesthetic success was assessed with electric pulp testing. Postoperative pain levels, participant preference, and adverse events were also assessed.

RESULTS

LE injections demonstrated significant reductions in PBF at all time intervals compared with baseline (P < .05), whereas KNS and MP did not. Pulpal anesthesia success rates were higher for LE (85%) compared with MP (35%) and KNS (5%). Participants reported significantly higher postoperative pain levels for KNS compared with LE and MP. Additionally, KNS was the least preferred of the anesthetics administered and resulted in more reported adverse events.

CONCLUSION

Although KNS showed no significant effect on PBF, it was not effective in achieving pulpal anesthesia as used in this study.

Mucoadhesive, Thermoreversible Hydrogel, Containing Tetracaine-Loaded Nanostructured Lipid Carriers for Topical, Intranasal Needle-Free Anesthesia

Recent advances have been reported for needle-free local anesthesia in maxillary teeth by administering a nasal spray of tetracaine (TTC) and oxymetazoline, without causing pain, fear, and stress. This work aimed to assess whether a TTC-loaded hybrid system could reduce cytotoxicity, promote sustained permeation, and increase the anesthetic efficacy of TTC for safe, effective, painless, and prolonged analgesia of the maxillary teeth in dental procedures. The hybrid system based on TTC (4%) encapsulated in nanostructured lipid carriers (NLC) and incorporated into a thermoreversible hydrogel of poloxamer 407 (TTCNLC-HG4%) displayed desirable rheological, mechanical, and mucoadhesive properties for topical application in the nasal cavity. Compared to control formulations, the use of TTCNLC-HG4% slowed in vitro permeation of the anesthetic across the nasal mucosa, maintained cytotoxicity against neuroblastoma cells, and provided a three-fold increase in analgesia duration, as observed using the tail-flick test in mice. The results obtained here open up perspectives for future clinical evaluation of the thermoreversible hybrid hydrogel, which contains TTC-loaded NLC, with the aim of creating an effective, topical, intranasal, needle-free anesthesia for use in dentistry.

Effect of precooling injection site and cold anesthetic administration on injection pain, onset, and anesthetic efficacy in maxillary molars with symptomatic irreversible pulpitis: a randomized controlled trial

OBJECTIVE

This randomized controlled clinical trial assessed the analgesic and anesthetic effects of precooling the injection site and administration of refrigerated 2% lignocaine HCl with 1:100,000 epinephrine (LE) in maxillary molars with symptomatic irreversible pulpitis (SIP).

MATERIALS AND METHODS

Sixty patients diagnosed with SIP (preoperative pain score ≥ 85 mm) in maxillary first molars were randomly allocated to two groups. In group I (control), topical gel was applied for a minute followed by conventional LE infiltration, whereas in group II (experimental), topical ice application for 15 s and refrigerated (4-6 °C) LE administration was done prior to endodontic treatment. The primary outcome measure was anesthetic efficacy that was defined as none to weak pain (≤ 36 mm) as measured on Heft Parker visual analog scale (HP-VAS) following access cavity preparation. Pain on injection and onset constituted the secondary outcome measures. The pain on injection was measured using HP-VAS, whereas the onset of anesthesia was assessed using an electric pulp tester (EPT) which was applied on the experimental tooth every minute until no response was elicited. Mann-Whitney U test was performed to analyze the data (p < 0.01).

RESULTS

Experimental group reported a success rate of 86.6% when compared to control group (26.6%) and a statistically significant reduction on injection pain (20.0 mm vs 54.5 mm) (p < 0.01). The onset of anesthesia for experimental group was 2.4 min which was also significantly lower than control group (4.5 min) (p < 0.01).

CONCLUSIONS

Cryotherapy can serve as an effective alternative to conventional anesthesia for achieving success, reduced pain, and faster onset during endodontic treatment of maxillary molars with SIP.

CLINICAL RELEVANCE

Precooling the injection site and cold LE administration can result in effective pulpal anesthesia during endodontic management of maxillary molars in SIP patients.

Local anaesthesia in dentistry: a review

Over the past century, there is perhaps no greater contribution to the practice of clinical dentistry than the development and application of local anaesthesia. What were once considered painful procedures have now been made routine by the deposition and action of local anaesthetics. This article will serve as a review of basic pharmacological principles of local anaesthesia, subsequent sequelae that can arise from their use, considerations when using local anaesthetics, and recent advances in the delivery of local anaesthetics.