Effect of topical anesthesia on pain during infiltration injection and success of anesthesia for maxillary central incisors

Hand-Holding's Effect on Children's Pain Perception and Anxiety during Dental Anesthetic Injections

Local anesthetic injections are an essential tool in dentistry, particularly in pediatric dentistry. The needle penetrating the tissue can cause stress, anxiety, and pain. Studies have shown that using touch may alleviate pain and reduce patient anxiety. Yet, this has not been tested in pediatric dental patients. Therefore, this study examined the effect of hand-holding on children undergoing local anesthetic injections. Its effect on children's pain perception was tested, with the hypothesis that pain perception would be lower for children whose hand was held by an assistant. Additionally, the study examined whether hand-holding would affect children's anxiety levels and cooperation. Fifty-five children, who underwent dental treatment within the Department of Pediatric Dentistry at Tel Aviv University, were recruited. The patients were randomly divided into two groups. In the study group, the assistant gently placed her hand on the patient's hand during the anesthetic injection. In the control group, the same treatment was performed without the hand being placed by the assistant. After the anesthetic injection, the child's pain and anxiety levels were assessed using visual analog scales (VAS). The patients' pulse was measured. The level of cooperation was evaluated using the "Frankl" scale. Interestingly, although the trends aligned with this study's hypotheses, no significant effect of hand-holding on pain, anxiety, or cooperation during anesthetic injections was found.

Comparative Assessment of Pain during Infiltration by a Two-stage Infiltration Technique: A Double-blind Clinical Trial

AIM

The aim of this study was to assess and compare the pain during infiltration by a modified two-stage local anesthetic infiltration technique under topical anesthesia (TA).

MATERIALS AND METHODS

In this cross-over double-blind study, 30 volunteers participated, where two groups were given single-stage infiltration and the other two had two-stage infiltrations. Depending upon the infiltration technique (one- or two-stage) and the use of TA, the patients were randomly divided into four groups. Local anesthesia (LA) was administered by infiltration into the mucobuccal fold of the maxillary central incisor, and the pain perceived during the infiltration in each group was recorded. The volunteers were recalled after 24 hours to assess the tenderness at the injection site. The volunteers were recalled 2 weeks after infiltration for the subsequent groups to assess the pain for this cross-over study.

RESULTS

A statistically significant difference was observed in the pain perceived when TA was used and when the infiltration was done in two stages. Regarding the pain at the site of injection after 24 hours, no significant difference was observed among the volunteers.

CONCLUSION

Topical anesthesia was effective in reducing the pain of injection when compared to placebo. The pain of injection is further reduced with a two-stage infiltration technique after TA application.

CLINICAL SIGNIFICANCE

Topical anesthesia can be used routinely before infiltration, and LA infiltration injections are less painful if administered in two stages.

Present status and future directions - Mechanisms and management of local anaesthetic failures

Pain control during root canal treatment is of utmost importance for both the patient and the dental practitioner and many studies have investigated ways of overcoming problems with gaining adequate anaesthesia during treatment. The PubMed and Cochrane databases were searched for evidence-based studies regarding local anaesthesia for root canal treatment. Many variables, including premedication, pain during needle insertion, pain on injection, premedication with various types of drugs, volume of anaesthetic solutions, supplemental anaesthetic techniques, and additives to the anaesthetic solutions, may influence pain perception during root canal treatment. Differences between teeth with healthy pulps versus those with irreversible pulpitis should be considered when the effects of variables are interpreted. There are several concerns regarding the methodologies used in studies that have evaluated anaesthesia success rates. There are some conditions that may help to predict a patient's pain during root canal treatment and these conditions could be overcome either by employing methods such as premedication with a non-steroidal anti-inflammatory drug prior to the treatment visit or by using supplementary anaesthetic techniques before or during the treatment. However, authors need to be more careful when reporting details of their studies to reduce concerns regarding their study bias.

Effects of different topical anesthetics on pain from needle insertion and injection, and the influence of anxiety in patients awaiting endodontic treatment

Objectives

This study aimed to evaluate the effects of 5% lidocaine and 2.5% lidocaine/2.5% prilocaine topical anesthetic on pain during needle insertion and infiltration injection in the labial mucosa of anterior maxillary teeth, and to assess the relationship between patients’ anxiety and pain scores.

Materials and Methods

The Modified Dental Anxiety Scale questionnaire was applied and recorded. Patients were randomly divided into 4 groups (n = 30), as follows: G1 group: 5% lidocaine and placebo for 1 minute, G2 group: 2.5% lidocaine/2.5% prilocaine and placebo for 1 minute, G3 group: 5% lidocaine and placebo for 3 minutes, and G4 group: 2.5% lidocaine/2.5% prilocaine and placebo for 3 minutes. Before the application of topical anesthesia, one side was randomly selected as the topical anesthesia and the contralateral side as the placebo. The pain levels were measured with Visual Analog Scale (VAS) immediately after needle insertion and injection and were compared. The correlation between anxiety and pain scores was analyzed.

Results

Administration of 5% lidocaine for 1 minute had significantly higher pain scores for both insertion and infiltration injection than the other groups (p < 0.05). There was a significant moderate positive correlation between dental anxiety and the injection-induced VAS pain score in the placebo side in all groups (p < 0.05).

Conclusions

Topical anesthetics significantly reduced the pain caused by both needle insertion and injection pain in comparison to the placebo side. The pain scores of patients with dental anxiety were lower on the topical anesthesia compared to the placebo side.

Trial Registration

Thai Clinical Trials Registry Identifier: TCTR20201217002

Local anesthesia in oral and maxillofacial surgery: A review of current opinion

Local anesthesia (LA) is the most important pain management process in oral and maxillofacial surgery. Safe and effective LA not only enable patients to obtain high-quality treatment, but also relieve the anxiety of patients when they come to the clinic. The choices of local anesthetic and injection methods determine the success of LA to a great extent. At present, in most countries or regions, common local anesthetics used in oral and maxillofacial surgery belong to amides and they are injected into patients' body mainly through block or infiltration anesthesia. In addition, the operators' technique level, patient's subjective psychology and anatomical variation of maxillofacial structure also have a strong influence on LA in dental clinic. Due to the existence of above factors, the worldwide success rates of LA in oral and maxillofacial surgery is very different. There are no specific LA methods that ensure 100% successful LA rates. Fortunately, the development of new local anesthetic and injection technology are providing us with new ideas to solve this problem. This review mainly report the new research progress on LA in oral and maxillofacial surgery in recent decades and help clinicians with dental LA operation.

Effect of Transcodent painless needles on injection pain in maxillary anterior infiltration: a split-mouth controlled randomized clinical trial

Objectives

The present study aimed to determine the pain perceived during supraperiosteal (infiltration) injection in anterior maxillary region by Transcodent painless needle tips in comparison to the regular needle tips.

Material and methods

In this split‐mouth controlled randomised clinical trial, 30 patients were selected as candidates for cosmetic treatment who needed infiltration injections on both sides of canine area. They were each administered 0.9 mL of Lidocaine HCl 2% with epinephrine 1:100,000 in the buccal vestibules using two types of needle tips, Transcodent painless needle tip or regular needle tip. Immediately after the injection, the pain was measured using a 100 mm visual analog scale. The level of pain was statistically analyzed in the two groups using the parametric paired t‐test. A 5% significance level was considered for statically significant difference between two means.

Results

In accordance with the results, the patients' level of pain were estimated as 18.3 ± 10.7 mm with Transcodent painless needle tips and 43.1 ± 13.1 mm in regular needle tip (p < 0.05).

Conclusion

The Transcodent painless needle showed considerable reduction of pain in the anterior maxillary infiltration when compared to the regular needle tips.

Does the use of topical anesthetics reduce the perception of pain during needle puncture and anesthetic infiltration? Systematic review and meta-analysis of randomized controlled trials

The objective of this systematic review was to assess whether the use of topical anesthetics reduces the perception of pain during puncture and anesthetic infiltration. Twenty-two randomized controlled clinical trials, published in English on or before August 6, 2020, were found in the PubMed/MEDLINE, Scopus, and Cochrane Library databases. Risk of bias was determined for randomization and other issues. A total of 1029 patients were evaluated using parameters such as type of topical anesthetic, application site, and pain (measured on a scale). Some studies assessed more than one topical anesthetic. Seventeen of them showed a reduction in pain from needle puncture and four from infiltration. Meta-analyses for some results showed considerable statistical heterogeneity. Regarding pain during needle puncture of the maxilla, statistically significant differences were observed in the topical anesthetics group, in both the vestibular (P = 0.0002) and palatal (P = 0.005) region. This was different from the mandible, for which there was no statistically significant difference (P = 0.07). With regard to pain caused by anesthetic infiltration in the maxilla, there was no difference in the use of anesthetic in relation to the control group (P = 0.11). Given these findings, using topical anesthetics only relieves pain during needle puncture and in the maxilla. PROSPERO 2020: CRD42020206362.

A Randomized Controlled Trial of Three Noninvasive Analgesic Techniques for the Prevention of Pain During Facial Injections

BACKGROUND

Injections are associated with a certain amount of pain, the tolerance of which can vary between individuals. With regard to noninvasive pain control techniques in subcutaneous injections, few studies with adequate levels of evidence and design quality exist to support any specific analgesic method.

OBJECTIVES

In this study, we evaluated the efficacy of 3 noninvasive analgesic techniques (cold, anesthetic cream, and vibration) during subcutaneous forehead injections in 100 healthy volunteers.

METHODS

This randomized, single-blind, controlled trial comprised 100 healthy volunteers. Every patient received 4 forehead injections of 0.1 mL physiological saline through 29G needles after 1 of 3 noninvasive analgesic techniques (cold, vibration, or anesthetic cream) or control treatment was applied to each injection site. The results were evaluated through a survey that included a visual analog scale for pain measurements.

RESULTS

All analgesic methods demonstrated better pain control than the no-treatment arm (P < 0.001), of which vibration performed better than the other analgesic techniques (P < 0.015 vs cold and P < 0.015 vs anesthetic cream). No differences were observed between cold and anesthetic cream. The average amount of pain per injection in males was higher than in females (P < 0.014).

CONCLUSIONS

Vibration analgesia effected significantly better pain control than cold and anesthetic cream. Nevertheless, the choice of anesthetic method should be adapted to the preferences and experiences of each patient to optimize pain control in procedures that involve subcutaneous injections.

LEVEL OF EVIDENCE: 2

The effectiveness of electronic pulsed soft tissue vibration compared with topical anaesthesia in reducing the pain of injection of local anaesthetics in adults: a randomized controlled split-mouth clinical trial

The purpose of this study was to evaluate the effectiveness of an electronic hand-held pulsed vibration device on the pain of local analgesia (LA) injection and physiologic changes. A prospective randomized controlled clinical trial using split-mouth (crossover) design was implemented. The control-side injection was performed after using topical anaesthesia. The experimental side injection was carried out without topical anaesthesia, but with the aid of a switched-on vibration device. Overall, 332 dental LA injections were given to 166 patients for routine exodontia. The pain at penetration and pain during injection were significantly lower in the experimental sides (vibrations sides) compared with those of the controls (P<0.001). Similarly, the heart rate changes at penetration and during injections were significantly lower in the experimental sides (P<0.001). The vibration device was clinically and statistically more effective than topical anaesthesia in the reduction of dental injection pain in adults, measured subjectively and objectively, regardless of the gender, injection technique (infiltration or block) or anxiety level.

Efficacy of Topical Benzocaine in Maxilla: A Randomized Controlled Trial

This study aims to compare the effect of topical anesthesia against the use of no topical agent on pain of needle penetration and local anesthesia deposition during buccal infiltration in anterior maxilla. In a randomized controlled trial, 100 adult participants were randomly allocated to the benzocaine group (received 20% benzocaine gel) and no benzocaine group (received no topical agent) prior to buccal infiltration in maxillary anterior teeth. A 27-gauge needle was used to deposit 2% lidocaine with 1:100,000 epinephrine. Pain of needle penetration and local anesthesia deposition was recorded separately using an 11-point Numeric Pain Rating Scale. Results showed that although 20% benzocaine significantly reduced pain on needle penetration during buccal infiltration in maxillary anterior teeth, the difference was small and the clinical significance is not clear. Topical anesthetic did not affect pain of local anesthetic deposition.

Ice versus lidocaine 5% gel for topical anaesthesia of oral mucosa - a randomized cross-over study

BACKGROUND

Topical anaesthesia is important to optimize pain control during dental injection. Our aim was to describe a new simple method for topical anaesthesia of oral mucosa and to compare the effectiveness of ice and lidocaine 5% gel for topical anaesthesia of oral mucosa.

METHODS

A total of 40 patients aged 10.7-19.5 years were included. The side and method of application were both randomized. Heart rate was recorded, and discomfort and pain were evaluated with a visual analogue scale (VAS). A paired t-test was used to compare mean values, a chi² test was used to compare proportions, and a Pearson correlation test was used to examine correlations between variables.

RESULTS

When ice was used, buccal injection VAS pain was rated lower (p = 0.044), and VAS discomfort was rated higher (p = 0.001), in comparison to when lidocaine 5% gel was used. There was no significant difference in relative heart rate change between ice and lidocaine 5% gel at either needle stick or injection. Lidocaine 5% gel produced a relative heart rate reduction after palatal injection (0.99 ± 0.06) while buccal injection produced an increased relative heart rate (1.02 ± 0.08) (p = 0.010). Unpleasant taste was more frequently reported when lidocaine 5% gel was used (p = 0.025). An application time of 1 min was sufficient for both ice and lidocaine 5% gel to achieve pain reduction from needle stick in buccal mucosa.

CONCLUSION

The cheap and readily available described method using ice for topical anaesthesia of oral mucosa before dental injection is an effective alternative to lidocaine 5% gel.

TRIAL REGISTRATION

The European Union Drug Regulating Authorities Clinical Trials Database EudraCT201300530531. Date of registration: February 10th, 2014.

Comparative Analysis of the Effectiveness of the Topical Administration of Benzocaine and EMLA® on Oral Pain and Tactile Sensitivity

Objectives

To compare the effectiveness of the topical administration of benzocaine and EMLA on oral pain and tactile sensitivity.

Materials and Methods

A randomized, double-blind, split-mouth clinical trial was carried out with 20 volunteers. The sensorial and quantitative tests were applied before the contact with topical anesthetic and after the application.

Results

In the superficial tactile perception test, when we compared each group singly, there were statistically significant values in the decrease of superficial tactile perception when compared to the moment prior to the application of anesthetic agents. For the sensitivity to mechanical pain, no statistical significant difference was observed at evaluated times. In the needle penetration test, in an intergroup analysis, we found a decrease in the pain sensitivity to needle penetration at 5 min (p=0.053) and at 10 min (p=0.019) after the contact of the anesthetic drug with the oral mucosa.

Conclusion

The application of topical anesthetic drugs reduces the discomfort associated with this procedure, mainly until the first 10 minutes. Only the needle penetration sensitivity test showed sufficient sensitivity to reveal a difference in the anesthetic effect between EMLA and benzocaine. This trial is registered with RBR-2N2GSW.

A Clinical Study on the Effect of Injection Sites on Efficacy of Anesthesia and Pulpal Blood Flow in Carious Teeth

This randomized clinical trial evaluated the efficiency of maxillary infiltration anesthesia in carious teeth at two different injection sites and their impact on the laser Doppler recordings of pulpal blood flow (PBF) during a caries excavation procedure. The null hypothesis tested was that there are no differences in the efficiency of anesthesia and PBF reduction between maxillary infiltrations at the two injection sites. One hundred twenty patients were divided into three groups according to the degree of carious lesion of their maxillary left central incisors (moderate caries, deep caries, or no caries). Forty patients in each group randomly received infiltrations over the root apex of maxillary left central incisors (site X) or over the midpoint of the line connecting the root apexes of both maxillary left central and lateral incisors (site Y) using 0.9 mL 2% lidocaine with 1:100,000 adrenaline. Teeth were pulp tested at five-minute intervals after injection except for the period of cavity cutting, which was done 12 minutes after injection. The PBF changes after injection were monitored by laser Doppler flowmetry. The observation period in this study was 60 minutes. Success of anesthesia was defined as no or mild pain on cavity cutting by visual analog scale recordings. Deep caries group showed significantly higher baseline PBF ( p<0.05). All groups showed 100% success of anesthesia and similar duration time ( p>0.05). Subgroups that had the injection at site Y showed significantly less reduction of PBF ( p<0.05). Cavity-cutting procedures increased the amplitude of the PBF around the lowest value after injection. Independent of the cavity depth, carious anterior teeth anesthetized by infiltration further from the apex had significantly less reduction on the pulpal blood flow compared with teeth anesthetized by infiltration at the apex.

The most painful site of maxillary anterior infiltrations

Background:

The purpose of this study was to determine the most painful site of infiltration injection in the anterior part of maxilla.

Materials and Methods:

This single-blinded clinical trial was conducted on thirty healthy volunteers. The participants received three maxillary infiltrations injected at the region of central and lateral incisors as well as canines at three separated appointments with a 2-week interval. The outcome variable was pain that measured immediately after needle insertion (time = 0) and during injection of anesthetic solution in 5, 30, and 55 s by a visual analog scale. Data were analyzed by SPSS software version 16 using Friedman test.

Results:

There was no statistically significant difference in terms of needle insertion pain and during injection (time = 0, 5, 30, and 55 s) (P = 0.319, P = 0.849, P = 0.627, and P = 0.939, respectively) in the three injection sites.

Conclusion:

The pain intensity of infiltration was not associated with injection sites in the anterior maxilla.

Effect of Corticosteroids on Pain Relief Following Root Canal Treatment: A Systematic Review

INTRODUCTION

Post-operative pain and flare-up may occur in up to 58% of patients following root canal treatment. The aim was to conduct a systematic review and a possible meta-analysis to determine the effect of glucocorticosteroid (GCS) on pain following root canal treatment.

METHODS AND MATERIALS

Scopus, MEDLINE and CENTRAL databases were searched up to 30th January 2017 with broad key words. In addition, the reference lists in eligible papers and text books were hand-searched. Assessment of the eligibility of papers and data extraction were performed by two independent reviewers.

RESULTS

Of 9891 articles, 18 were recruited as eligible papers. Most of these papers showed pain reducing effect of GCS on post-endodontic pain. Because of wide heterogeneity among the recruited papers, it was not possible to perform meta-analysis.

CONCLUSION

Based on the results of this systematic review, there is a vast heterogeneity amongst articles regarding the use of GCS and their effect on post-operative pain after endodontic treatment. Further investigations with similar methods and materials are needed before meta-analysis on the effect of GCS on post-operative pain following root canal treatment can be performed.

Development and Evaluation of a Novel Mucoadhesive Film Containing Acmella oleracea Extract for Oral Mucosa Topical Anesthesia

Purpose

To develop an anesthetic mucoadhesive film containing Acmella oleracea (jambu) extract for topical use on oral mucosa.

Methods

Ethanolic extracts from aerial parts of jambu were prepared by maceration. Pigment removal was obtained by adsorption with activated carbon. Three mucoadhesive films were developed using a film casting method: 10 or 20% of crude jambu extract (10% JB and 20% JB), and 10% of crude jambu extract treated with activated carbon (10% JBC). The mucoadhesive films were characterized regarding their uniformity, thickness, pH, and spilanthol content, and their stability was evaluated during 120 days. Gas chromatography was used to quantify the amount of spilanthol. In vitro tests determined the permeation of spilanthol across pig esophageal epithelium mucosa in Franz diffusion cells. Topical anesthetic efficacy was assessed in vivo using a tail flick test in mice.

Results

The three mucoadhesive films showed physical stability and visual appearances suitable for use on oral mucosa. The permeation study revealed that the spilanthol from 10% JBC presented higher flux and permeability coefficient values, compared to 10% or 20% JB (p < 0.001). Moreover, 10% JBC showed better topical anesthetic efficacy than the other films (p < 0.01).

Conclusion

Mucoadhesive film containing crude extract of jambu treated with activated carbon is a potential alternative for oral, topical use, encouraging future clinical studies.

Indexing of Iranian Publications in Well-known Endodontic Textbooks: A Scientometric Analysis

Introduction:

Quoting an article in well-known textbooks is held as a credit for that paper. The numbers of Iranian publications mentioned in endodontic textbooks have increased during recent years. The aim of this investigation was to evaluate the number of Iranian articles quoted in eminent endodontic textbooks.

Methods and Materials:

Three known textbooks (Ingle’s Endodontics, Seltzer and Bender’s Dental Pulp and Cohen’s Pathways of the Pulp) were chosen and all the editions of the textbooks since 2000 were investigated for quoted Iranian publications. Only Iranian authors with affiliations from a domestic university were chosen. All references at the end of each chapter were read by hand searching, and results were noted. The trend and percentage of Iranian publications in different editions of the textbooks were also calculated. The number of citations of these publications in Google Scholar and Scopus databases were also obtained.

Results:

The number of Iranian publications in all well-known textbooks have notably increased since 2000. The number and percentage of Iranian publications in the latest edition of Cohen’s Pathways of the Pulp was higher compared to other textbooks as well as the previous edition of the same text.

Conclusion:

Number and percentage of Iranian publications in the field of endodontics in all three textbooks have remarkably increased since 2000.

Efficacy of Articaine and Lidocaine for Buccal Infiltration of First Maxillary Molars with Symptomatic Irreversible Pulpitis: A Randomized Double-blinded Clinical Trial

Introduction:

The aim of the present study was to compare the efficacy of 2% lidocaine to 4% articaine in buccal infiltration of maxillary first molars with irreversible pulpitis. Moreover, the effect of root length on success of anesthesia irrespective of the type of anesthetic agent was assessed.

Methods and Materials:

Fifty patients suffering from painful maxillary first molars with irreversible pulpitis received an infiltration injection of either 4% articaine with 1:100000 epinephrine or 2% lidocaine with 1:80000 epinephrine. Each patient recorded their pain score in response to a cold test on a Heft-Parker visual analogue scale (VAS) before commencing the treatment, 5 min following injection, during access preparation, after pulp exposure and during root canal instrumentation. No or mild pain at any stage was considered a success. Data were analyzed using the multivariate logistic regression analysis, chi-square and t tests.

Results:

Finally, 47 out of 50 patients were eligible to be included in this study. The anesthetic success rates in the lidocaine and articaine groups were 56.52% and 66.67%, respectively and the difference was not significant (P=0.474). Irrespective of the anesthetic agent, the length of the palatal root (Odds Ratio=0.24, P=0.007) had an adverse effect on anesthetic success. There was an association between longer palatal root length and anesthetic failure.

Conclusion:

No significant difference was found between 2% lidocaine and 4% articaine in terms of anesthetic success in maxillary first molars with irreversible pulpitis. The length of the palatal root had a significant negative influence on anesthetic success.

The success rate of bupivacaine and lidocaine as anesthetic agents in inferior alveolar nerve block in teeth with irreversible pulpitis without spontaneous pain

Objectives

Achieving adequate anesthesia with inferior alveolar nerve blocks (IANB) is of great importance during dental procedures. The aim of the present study was to assess the success rate of two anesthetic agents (bupivacaine and lidocaine) for IANB when treating teeth with irreversible pulpitis.

Materials and Methods

Sixty volunteer male and female patients who required root canal treatment of a mandibular molar due to caries participated in the present study. The inclusion criteria included prolonged pain to thermal stimulus but no spontaneous pain. The patients were randomly allocated to receive either 2% lidocaine with 1:80,000 epinephrine or 0.5% bupivacaine with 1:200,000 epinephrine as an IANB injection. The sensitivity of the teeth to a cold test as well as the amount of pain during access cavity preparation and root canal instrumentation were recorded. Results were statistically analyzed with the Chi-Square and Fischer's exact tests.

Results

At the final step, fifty-nine patients were included in the study. The success rate for bupivacaine and lidocaine groups were 20.0% and 24.1%, respectively. There was no significant difference between the two groups at any stage of the treatment procedure.

Conclusions

There was no difference in success rates of anesthesia when bupivacaine and lidocaine were used for IANB injections to treat mandibular molar teeth with irreversible pulpitis. Neither agent was able to completely anesthetize the teeth effectively. Therefore, practitioners should be prepared to administer supplemental anesthesia to overcome pain during root canal treatment.

A new protocol to evaluate the effect of topical anesthesia

This double-blind, placebo-controlled, randomized cross-over clinical experimental study tested the reliability, validity, and sensitivity to change of punctuate pain thresholds and self-reported pain on needle penetration. Female subjects without orofacial pain were tested in 2 sessions at 1- to 2-week intervals. The test site was the mucobuccal fold adjacent to the first upper right premolar. Active lidocaine hydrochloride 2% (Dynexan) or placebo gel was applied for 5 minutes, and sensory testing was performed before and after application. The standardized quantitative sensory test protocol included mechanical pain threshold (MPT), pressure pain threshold (PPT), mechanical pain sensitivity (MPS), and needle penetration sensitivity (NPS) assessments. Twenty-nine subjects, mean (SD) age 29.0 (10.2) years, completed the study. Test-retest reliability intraclass correlation coefficient at 10-minute intervals between examinations was MPT 0.69, PPT 0.79, MPS 0.72, and NPS 0.86. A high correlation was found between NPS and MPS (r = 0.84; P < .001), whereas NPS and PPT were not significantly correlated. The study found good to excellent test-retest reliability for all measures. None of the sensory measures detected changes in sensitivity following lidocaine 2% or placebo gel. Electronic von Frey assessments of MPT/MPS on oral mucosa have good validity.

A new method of topical anesthesia by using anesthetic solution in a patch

INTRODUCTION

We investigated the effects of topical anesthesia of the oral mucosa by using an adhesive patch instilled with 2% lidocaine hydrochloride solution.

METHODS

The subjects were 20 healthy adult volunteers who gave written informed consent. Each patient was treated in a randomized crossover fashion with a hemostatic adhesive patch instilled with one of the following agents: 2% lidocaine hydrochloride with 12.5 μg/mL epinephrine, 2% lidocaine hydrochloride, 20% ethyl aminobenzoate, or physiological saline solution. A cotton ball containing 20% ethyl aminobenzoate was also tested. The adhesive patch or cotton ball was placed on the gingivobuccal fold of the maxillary right canine for 2 or 5 minutes. Then, a 33-gauge or 30-gauge needle was inserted to a depth of 2 mm. Insertion pain was evaluated with a visual analog scale (VAS) and a 4-level verbal rating scale immediately after needle removal. Efficacy of analgesia was calculated from the verbal rating scale.

RESULTS

The VAS was lower and the efficacy of analgesia was higher on 33-gauge needle insertion than on 30-gauge needle insertion in all treatments. The VAS was also significantly lower and the efficacy of analgesia was higher in the lidocaine groups than in the other groups. Adding epinephrine did not enhance the anesthetic effect of lidocaine hydrochloride.

CONCLUSIONS

Topical mucosal anesthesia with an adhesive patch containing 2% lidocaine hydrochloride solution is simple and may be more effective than conventional methods.