Effects of Prilocaine local anaesthetic solutions on pulpal blood flow in maxillary canines

Abstract The effects of prilocaine local anaesthetic solutions on pulpal blood flow (PBF) in maxillary canines were investigated in nine adult subjects. Buccal infiltration of 2 ml of the following solutions were carried out: 3% prilocaine; 3% prilocaine with 0.03 IU/ml felyprcssin; and 3% prilocaine with 1:100,000 adrenaline. Blood (low in the anaesthetized tooth was monitored by a laser Doppler flowmeter and data stored in a computer. An electric pulp tester was used to assess pulpal anaesthesia. The duration of anaesthesia was recorded. After administration of plain prilocaine, PBF changed little throughout the experiment in all nine subjects. When prilocaine with felypressin was injected, PBF fluctuated greatly, but there was no sustained increase or decrease. In comparison, prilocaine with adrenaline caused a significant decline in PBF in every subject (p<0.05), but then gradually started lo return to the pre-injection level; there was no such change in PBF of the contralateral tooth. Injection of 3% plain prilocaine achieved a short duration of pulpal anaesthesia (median 7 min) in only three subjects. When prilocaine with felypressin was injected, eight out of nine subjects experienced pulpal anaesthesia (median duration 10.5 min). Injection of prilocaine with adrenaline caused pulpal anaesthesia in six of nine subjects (median duration 10.5 min). The use of vasoconstrictors with prilocaine anaesthetics had less pronounced effects on blood How and shorter periods of anaesthesia than those reported previously for lignocaine with adrenaline.     

Effects of adrenaline and felypressin (octapressin) on blood flow and sensory nerve activity in the tooth

The present investigations in cats were designed to study the effects of local anaesthetics containing adrenaline and felypressin (octapressin) on dental pulp function.

Intradental sensory nerve excitability was measured using electrodes placed in dentinal cavities in canine teeth. Changes in pulp blood flow were measured using the disappearance rate of a radioactive tracer placed in the same cavities.

Injections (0.5 ml) of lidocaine (20 mg/ml) - adrenaline (12.5 μg/ml) or prilocaine (30 mg/ml) - octapressin (0.54 μg/ml) were given supraperiosteally in the apical area of the tooth. Adrenaline either alone or with lidocaine caused almost complete inhibition of pulp blood flow within a few minutes. This effect was followed by a total inhibition of the sensory nerve activity. In most cases there was a recovery of both functions after 3 hours. Octapressin, on the other hand, had no inhibitory effects on pulp blood flow or sensory nerve activity. Lidocaine and prilocaine were also without effect.

These findings indicate a different mode of action of the two vasoconstrictors and suggest that octapressin may be preferred in infiltration anaesthesia during treatment of the vital tooth.     

Local anaesthesia in elderly patients. An experimental study of oral infiltration anaesthesia

The proportion of elderly people is increasing. Normal ageing causes a reduced physiological capacity and ability to meet challenges. In future more elderly people will have functioning natural dentitions and undergo routine dental procedures for which local anaesthesia is required. In this experimental investigation the effect of infiltration anaesthesia from 3 commonly used agents was compared in healthy elderly and young subjects. The subjects comprised 40 volunteers and the anaesthetic agents tested were lidocaine (20 mg/ml) with epinephrine (12.5 micrograms/ml), prilocaine (30 mg/ml) with felypressin (0.54 microgram/ml) and mepivacaine (30 mg/ml). The elderly subjects had a highly significantly shorter onset time compared to the young group. There was no statistically significant difference in duration of tooth anaesthesia between lidocaine with epinephrine and prilocaine with felypressin. Because elderly people have lower drug tolerance, prilocaine with felypressin is therefore recommended for routine dentistry.     

Plasma variations in stress markers: Clinical trial of two anesthetics used in regional block in the extraction of impacted inferior third molars

Objectives: Was to evaluate the effect of different regional anesthetics (articaine with epinephrine versus prilocaine with felypressin) on stress in the extraction of impacted lower third molars in healthy subjects. Sutdy Desing: A prospective single-blind, split-mouth cross-over randomized study was designed, with a control group. The experimental group consisted of 24 otherwise healthy male volunteers, with two impacted lower third molars which were surgically extracted after inferior alveolar nerve block (regional anesthesia), with a fortnight’s interval: the right using 4% articaine with 1:100.000 epinephrine, and the left 3% prilocaine with 1:1.850.000 felypressin. Patients were randomized for the first surgical procedure. To analyze the variation in four stress markers, homovanillic acid, 3-methoxy-4-hydroxyphenylglycol, prolactin and cortisol, 10-mL blood samples were obtained at t = 0, 5, 60, and 120 minutes. The control group consisted of 12 healthy volunteers, who did not undergo either extractions or anesthetic procedures but from whom blood samples were collected and analyzed in the same way. Results: Plasma cortisol increased in the experimental group (multiple range test, P<0.05), the levels being significantly higher in the group receiving 3% prilocaine with 1:1.850,000 felypressin (signed rank test, p<0.0007). There was a significant reduction in homovanillic acid over time in both groups (multiple range test, P<0.05). No significant differences were observed in homovanillic acid, 3-methoxy-4-hydroxyphenylglycol or prolactin concentrations between the experimental and control groups. Conclusions: The effect of regional anesthesia on stress is lower when 4% articaine with 1:100,000 epinephrine is used in this surgical procedure. Key words:Stress markets, epinephrine versus felypressin.     

Palatal needle-free anesthesia for upper molars extraction. A randomized clinical trial

BackgroundThe aim of this study was to compare the ability of liposomal and non-liposomal lidocaine and prilocaine in hydrogel formulations to promote topical anesthesia in palatal mucosa during upper molar extractions.MethodsIn this randomized, cross over, triple-blinded clinical trial, a liposomal and a non-liposomal formulation of the eutectic mixture of local anesthetics, 2.5% lidocaine and 2.5% prilocaine, were used to promote palatal anesthesia without the local anesthetic infiltration during bilateral upper molars extractions.ResultsFrom the total of 40 patients included in this study, the non-liposomal eutectic lidocaine-prilocaine formulation failed in 40% of cases, unlike the liposomal formulation, which was effective for all patients (Fisher's exact test, p < 0.0001). Furthermore, the liposomal formulation (26.75 ± 7,47 min) induced longer anesthesia duration (t-test, p < 0.0001) than the non-liposomal formulation (16.78 ± 4.75 min). No mucosal ulceration or discomfort was reported for both formulations.ConclusionThe liposomal formulation was able to induce adequate anesthesia in palatal mucosa during dental extraction, avoiding the local anesthetic infiltration. For the first time, a topical formulation allowed upper molars surgical removal without injection of any local anesthetic agent into palatal mucosa in adults.     

The effectiveness of two local analgesic preparations in reducing haemorrhage during periodontal surgery

A comparison was made of the effectiveness of two local analgesic preparations, lignocaine 2 per cent/adrenaline 1 in 80,000 and prilocaine 3 per cent/felypressin 0·03 I.U. per ml., in reducing operative haemorrhage during periodontal surgery. Blood-loss occurring during the surgical procedure was measured using a colorimetric technique. It was found that on average over four times as much bleeding occurred when prilocaine/felypressin was the analgesic than when lignocaine/adrenaline was used. The increased haemorrhage experienced when prilocaine/felypressin analgesia was used made the procedure more difficult and resulted in a higher incidence of postoperative dressing displacement.     

The effects of two different dental local anesthetic solutions on plasma potassium levels during third molar surgery

The influence of two different dental local anesthetic solutions on plasma potassium levels during third molar surgery has been investigated in a single-blind cross-over study in twelve volunteers. The solutions employed were 2% lidocaine (xylocaine) containing 1:80,000 epinephrine and 3% prilocaine (Citanest) containing 0.03 IU/ml felypressin. The different treatments produced similar effects on blood pressure and heart rate. However, the effect on plasma potassium levels differed significantly in the early postinjection period.     

A comparative study on the retention of 3H lignocaine and 3H prilocaine in the presence of various vasoconstrictors

A bstract — The efficacy of adrenaline, noradrenaline, and a mixture of adrenaline and felypressin in enhancing the retention of either prilocaine or lignocaine at an injection site has been tested in vivo using the rat tongue as the experimental model. It was found that adrenaline in equivalent concentrations was more effective than noradrenaline. The addition of felypressin to the adrenaline/prilocaine mixture further enhanced the retention of the local anaesthetic.     

Prilocaine induced methaemoglobinaemia in a medically compromised patient. Was this an inevitable consequence of the dose administered?

Patient M, a 45-year old female, was admitted for extractions with local anaesthetic, sedation and monitoring. This was to be carried out on an in patient basis due to the patient's extensive medical history which included rheumatic heart disease, previous deep vein thrombosis and severe ulcerative colitis. Patient M also gave a history of allergy to penicillin and lignocaine. The procedure was completed without incident, local anaesthesia having been achieved using Citanest with Octapressin (prilocaine 30 mg/ml and felypressin 0.03 unit/ml 2 ml cartridge). However, on recovery Patient M's oxygen saturations dropped to 90% on air and although she had no symptoms, the levels could not be improved with supplemental oxygen. A diagnosis of methaemoglobinaemia (MetHb) was established, a rare complication associated with the administration of prilocaine. Patient M was transferred to the high dependency unit and was given methylthioninium chloride (methylene blue) intravenously. Her oxygen saturations quickly returned to normal and she was discharged the following day. This case highlights issues relating to the risk of developing MetHb, what is considered the maximum safe dose of prilocaine and some incongruities the authors feel exist in the literature.     

3D-printed titanium surgical guides for extraction of horizontally impacted lower third molars

Objectives

This prospective study introduced a digitally designed sectioning guide and evaluated its feasibility for the extraction of horizontally impacted lower third molars.

Materials and methods

This study included 38 horizontally impacted lower third molars, randomly divided into experimental and control groups. The teeth were extracted using a 3D-printed titanium surgical guide in the experimental group; free-hand extractions were performed in the control group. The surgical duration, tooth sectioning duration, cortical bone perforation, and postoperative complications, including pain, swelling, trismus, dry socket, infection, and hemorrhage, were evaluated.

Results

Although not statistically significant, guided surgery tended to reduce the number of tooth sectioning steps compared to free-hand extractions. There were no cases of cortical bone perforation in the experimental group. Although the surgical duration was greater in the experimental group (p < 0.05), there were no differences in postoperative pain, swelling, and trismus. There were no cases of postoperative infection and hemorrhage in either group.

Conclusions

3D-printed titanium surgical guides had superior accuracy and safety compared to free-hand surgery. Further studies with larger sample sizes are required to verify these findings.

Clinical relevance

The template improved the safety of tooth sectioning during impacted lower third molar surgery and resulted in a more predictable extraction. The narrow sectioning groove could fit comfortably with hypertrophic soft tissues in the posterior mandible.

     

Effects of adrenaline and felypressin (octapressin) on blood flow and sensory nerve activity in the tooth.

The present investigations in cats were designed to study the effects of local anaesthetics containing adrenaline and felypressin (octapressin) on dental pulp function. Intradental sensory nerve excitability was measured using electrodes placed in dentinal cavities in canine teeth. Changes in pulp blood flow were measured using the disappearance rate of a radioactive tracer placed in the same cavities. Injections (0.5 ml) of lidocaine (20 mg/ml) - adrenaline (12.5 microng/ml) or prilocaine (30 mg/ml) - octapressin (0.54 microng/ml) were given supraperiosteally in the apical area of the tooth. Adrenaline either alone or with lidocaine caused almost complete inhibition of pulp blood flow within a few minutes. This effect was followed by a total inhibition of the sensory nerve activity. In most cases there was a recovery of both functions after 3 hours. Octapressin, on the other hand, had no inhibitory effects on pulp blood flow or sensory nerve activity. Lidocaine and prilocaine were also without effect. These findings indicate a different mode of action of the two vasoconstrictors and suggest that octapressin may be preferred in infiltration anaesthesia during treatment of the vital tooth.     

Plasma levels of lidocaine, o-toluidine, and prilocaine after application of 8.5 g Oraqix in patients with generalized periodontitis: effect on blood methemoglobin and tolerability

Oraqix, a novel non-injectable anesthetic gel containing lidocaine and prilocaine and a thermosetting agent has been developed to provide localized anesthesia in periodontal pockets during scaling/root planing (SRP). The aim of this open study was to determine the plasma levels of lidocaine and prilocaine following application of 8.5 g Oraqix (5 cartridges) to 11 patients with generalized periodontitis (> or = 49% of tooth pockets > or = 5 mm and > or = 23% of pockets > or = 6 mm). Oraqix was applied to the pockets during periodontal probing and SRP over a 2.6 3.4 h period. Blood samples were collected up to 10 h after the start of application of Oraqix. Peak plasma levels of lidocaine (0.16-0.55 mg/L) and prilocaine (0.05-0.18 mg/L) occurred 2.0-3.7 h and 2.0-3.3 h, respectively, after the start of application of Oraqix. These levels are well below threshold levels for initial signs of central nervous system (CNS) toxicity. In conclusion, application of 8.5 g Oraqix (212.5 mg of lidocaine base and 212.5 mg of prilocaine base) in periodontal pockets was well tolerated and displayed a wide safety margin with respect to plasma levels normally associated with systemic toxicity.     

Plasma levels of lidocaine,o-toluidine,and prilocaine after application of 8.5 g Oraqix® in patients with generalized periodontitis: effect on blood methemoglobin and tolerability

Oraqix®, a novel non-injectable anesthetic gel containing lidocaine and prilocaine and a thermosetting agent has been developed to provide localized anesthesia in periodontal pockets during scaling/root planing (SRP). The aim of this open study was to determine the plasma levels of lidocaine and prilocaine following application of 8.5 g Oraqix (5 cartridges) to 11 patients with generalized periodontitis ( &#83 49% of tooth pockets &#83 5 mm and &#83 23% of pockets &#83 6 mm). Oraqix was applied to the pockets during periodontal probing and SRP over a 2.6-3.4 h period. Blood samples were collected up to 10 h after the start of application of Oraqix. Peak plasma levels of lidocaine (0.16-0.55 mg/L) and prilocaine (0.05-0.18 mg/L) occurred 2.0-3.7 h and 2.0-3.3 h, respectively, after the start of application of Oraqix. These levels are well below threshold levels for initial signs of central nervous system (CNS) toxicity. In conclusion, application of 8.5 g Oraqix (212.5 mg of lidocaine base and 212.5 mg of prilocaine base) in periodontal pockets was well tolerated and displayed a wide safety margin with respect to plasma levels normally associated with systemic toxicity.     

Effects of dental local anaesthetics in cardiac transplant recipients

OBJECTIVE: To investigate the cardiovascular responses of cardiac transplant recipients to dental local anaesthetic solutions with and without epinephrine (adrenaline). MATERIALS AND METHODS: A clinical study employing 30 patients (20 cardiac transplant recipients and ten healthy) awaiting gingival or minor oral surgery under local anaesthesia receiving either 4.4 ml lidocaine (lignocaine) with 1:80,000 epinephrine or 4.4 ml 3% prilocaine with 0.031 U/ml felypressin. RESULTS: Cardiac transplant patients experienced a significant tachycardia 10 minutes after injection of the epinephrine-containing solution. No significant change in heart rate was detected after the injection of an epinephrine-free solution. Blood pressure was not affected. Periodontal surgery did not affect the responses to the local anaesthetics in the transplant recipients. CONCLUSIONS: The cardiovascular response to dental local anaesthesia in cardiac transplant recipients is governed by the solution injected.     

A pharmacokinetic study of a topical anesthetic (EMLA®) in mouse soft tissue laceration

The use of topical anesthesia instead of injection of local anesthetics for managing soft tissue lacerations in the emergency situations may be a relief for both patients and surgeons. Topical anesthesia in the form of a cream eutectic mixture of local anesthetics (EMLA^®) containing 2.5% lidocaine and 2.5% prilocaine has been reported as an efficient anesthetic on skin before venipuncture anesthesia and as an alternative to injection anesthesia in some minor surgery situations. The aim of this study was to compare the pharmacokinetics of EMLA^® when applied in a laceration with topical skin application in the mouse. A total of 120 Albino Laboratory‐bred strain mouse (BALB‐c) male mice were divided into three groups with regard to application mode of EMLA^®. Group A: with laceration, 48 mice; Group B: on intact shaved skin, 48 mice; Group C: control group (24 mice) with same procedures but without application of EMLA^®. Blood levels were collected at 0, 10, 20, 30, 45, 60, 75, and 90 min post‐EMLA^® application. Plasma sample analysis was carried out by employing liquid chromatography coupled with tandem mass spectrometric (LC‐MS/MS) method, and the pharmacokinetic analysis of the mouse plasma samples was estimated by standard non‐compartmental methods. The pharmacokinetic parameters of lidocaine and prilocaine were significantly altered following EMLA^® application to lacerated mouse skin in contrast to intact skin. The absorption of lidocaine and prilocaine was rapid following application of EMLA^® to lacerated and intact mouse skin. Maximum drug plasma concentration (C_max) and area under the drug plasma concentration–time curve (AUC) values of lidocaine were significantly increased by 448.6% and 161.5%, respectively, following application of EMLA to lacerated mouse skin in comparison with intact mouse skin. Similarly, prilocaine's C_max and AUC values were also increased by 384% and 265.7%, respectively, following EMLA application to lacerated mouse skin, in contrast to intact skin. Further pharmacokinetic studies on different carriers of lidocaine/prilocaine are warranted before any firm conclusions for the clinic can be drawn.     

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis

Objectives

Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence.

Materials and methods

Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control.

Results

Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence.

Conclusion

Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

     

Anesthetic Efficacy of a Combination of 4% Prilocaine/2% Lidocaine with Epinephrine for the Inferior Alveolar Nerve Block: A Prospective,Randomized, Double-blind Study

Introduction

Prilocaine plain has a high pH and concentration (4%), which could decrease the pain of injection and increase success. The purpose of this study was to compare pain associated with anesthetic solution deposition and the degree of pulpal anesthesia obtained with the combination of prilocaine and lidocaine versus a lidocaine and lidocaine combination when used for inferior alveolar nerve blocks (IANBs).

Anesthetic Comparisons of 4% Concentrations of Articaine,Lidocaine, and Prilocaine as Primary Buccal Infiltrations of the Mandibular First Molar: A Prospective Randomized,Double-blind Study

Introduction

Studies have shown the superiority of 4% articaine with 1:100,000 epinephrine over 2% lidocaine with 1:100,000 epinephrine when used as a primary buccal infiltration of the mandibular first molar. A study using other 4% anesthetic formulations may help determine the role of concentration in the increased efficacy of 4% articaine. The authors conducted a prospective randomized, double-blind, crossover study comparing the pulpal anesthesia obtained with 4% concentrations of articaine, lidocaine, and prilocaine formulations as primary buccal infiltrations of the mandibular first molar.

Methods

Sixty asymptomatic adult subjects randomly received a primary mandibular buccal first molar infiltration of 1.8 mL 4% articaine with 1:100,000 epinephrine, 4% lidocaine with 1:100,000 epinephrine, and 4% prilocaine with 1:200,000 epinephrine in 3 separate appointments. An electric pulp tester was used to test the first molar for anesthesia in 3-minute cycles for 60 minutes after the infiltrations. Successful anesthesia was defined as 2 consecutive 80/80 readings.

Results

The success rate for the 4% articaine formulation was 55%, 33% for the 4% lidocaine formulation, and 32% for the 4% prilocaine formulation. There was a significant difference between articaine and both lidocaine (P = .0071) and prilocaine (P = .0187) formulations.

Conclusions

A 4% articaine formulation was statistically better than both 4% lidocaine and 4% prilocaine formulations for buccal infiltration of the mandibular first molar in asymptomatic mandibular first molars. However, the success rate of 55% is not high enough to support its use as a primary buccal infiltration technique in the mandibular first molar.     

The influence of two different dental local anaesthetic solutions on the haemodynamic responses of children undergoing restorative dentistry: a randomised, single-blind, split-mouth study

OBJECTIVES: This investigation was designed to study the haemodynamic effects of two different local anaesthetic solutions during restorative dental treatment in children. DESIGN: A randomised, single-blind, split-mouth cross-over design was employed using children undergoing bilaterally similar restorative treatments over two visits. SETTING: The study was performed in a dental hospital paediatric dentistry department. METHODS: Ten children participated. At one visit the local anaesthetic was 2% lidocaine (lignocaine) with 1:80,000 epinephrine (adrenaline); at the other the anaesthetic was 3% prilocaine with 0.03IU/ml felypressin. Local anaesthetic was administered at a dose of 0.5 ml/10 kg body weight. Blood pressure and heart rate were measured before and during treatment with an automatic blood pressure recorder. Data were analysed by ANOVA and Student's paired t test. RESULTS: Significant differences between treatments in diastolic blood pressure (F = 2.37; P = 0.05) and heart rate (F = 2.98; P< 0.02) were noted. The heart rate increased ten minutes following the injection of the epinephrine-containing solution. The diastolic blood pressure fell 20 minutes after injection of lidocaine with epinephrine. CONCLUSION: The choice of local anaesthetic solution influences the haemodynamic response during restorative treatment in children.     

A bioadhesive delivery system as an alternative to infiltration anesthesia

Objective. The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry.Study design. The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4…). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables.Results. Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%.Conclusion. The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.