+ + = Local. Traditional local anaesthetics. Local anaesthesia for the 21 st Century an update. New Local Anaesthetics and Equipment

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1 BSDHT Liverpool ACC 10 th November 2012 Local anaesthesia for the 21 st Century an update Traditional local anaesthetics Lidocaine Prilocaine Mepivacaine Dr Nigel D Robb Reader in Restorative Dentistry New Local Anaesthetics and Equipment Importance of local anaesthesia in dentistry Articaine Phentolamine mesylate (OraVerse) Oraqix Computer controlled delivery systems The severe pain caused by diseases of teeth and jaw is a sign of the importance of these parts of the body. Local anaesthesia is an invaluable good for a dentist. It is his commitment to have a very good command of it in all scientific and technical aspects. Guido Fischer 1911 Use of vasoconstrictors I read about the possibility to produce an extract of the adrenal gland of animals which constricts blood vessels. A few days later I got a small amount of this extract, mixed it up with cocaine and injected it into my forearm. Immediately I knew that this was the dawn of a new period of local anaesthesia. Heinrich Braun 1900 concentration 1: Drug The brilliant Formula = Local Anaesthesia Delivery + + Technique = System Outcome 1

2 Choice of local anaesthetic agent Lidocaine (2%) and epinephrine (1:80 000) Gold standard in UK Active in 2-3 mins (infiltration) Duration mins Max dose 4.4mg/kg up to 300mg maximum Role of lidocaine First choice local anaesthetic in UK clinical practice Currently routine choice Prilocaine 3% IU felypression 2.2ml cartridges 30mg prilocaine and 0.54 g felypressin / ml Maximum safe dose of prilocaine 6mg/kg up to maximum of 400mg 1/10 th rule does not apply maximum 6 cartridges Role of prilocaine and felypressin Use when epinephrine best avoided Allergy to reducing agent Acute coronary syndromes Unstable angina Refractory arrythmias Concurrent use of cocaine or other illicit stimulants Felypressin and ischaemic heart disease Can cause coronary artery constriction Limit dose to 3 cartridges in patients with ischaemic heart disease Mepivacaine 3% or 2% + 1: epinephrine 2.2ml cartridges 30mg or 20mg mepivacaine and 10 g epinephrine per ml Max dose 4.4mg/kg 4 up to maximum of 300mg 1/10 th rule for 2% not for 3% - up to 6.8 cartridges for 2%, but only 4.5 cartridges for 3% 2

3 Role of mepivacaine Articaine HCL Use plain solution when epinephrine contraindicated Better for blocks than infiltrations 2% with epinephrine comparable with lidocaine, but slightly shorter duration of action 1974 Choice of local anaesthetic agent Articaine (4%) with adrenaline epinephrine (1: or 1: ) Advantages of short half life (30mins) Use serially toxicity less likely Now emerging evidence of improved efficacy / diffusing power etc Maximum dose 7mg/kg Articaine Marketed for improved diffusing properties Makes IAN Blocks obsolete has intense penetrating ti and spreading powers. Infiltration is possible in the mandible eliminating the need for mandibular block. Articaine Xylocaine has intense penetrating and spreading powers. Infiltration is possible in the mandible eliminating the need for mandibular block. Bremer et al, 1948 Difficult to demonstrate Recent studies show articaine more effective in buccal infiltration next to molars and upper lateral incisors Articaine This review supports the argument that articaine compared with lidocaine provides a higher rate of success with comparable safety to lidocaine when used for infiltrations or blocks Causes slightly more post injection pain 3

4 Rcommendation that 4% articaine (+ 1: epinephrine) to replace lidocaine (+ 1: epinephrine) Articaine Non surgical paraesthesias??? Thus there is an urgent need for further studies focused on the neurotoxicity of local anaesthetics with specific focus on articaine 4%. Until factual information is available, a preference for other formulations to 4% articaine may be justified, especially for mandibular block anaesthesia. Hillerup and Jensen, 2006 Non surgical paraesthesias??? Regarding articaine, the conclusion is the safety profile of the drug has not changed since its launch (1998). Thus, no medical evidence exists to prohibit the use of articaine Pharmacovigilance Working Party of EU, 2006 Non surgical paraesthesias??? Study of 53 patients (1/1/ /12/2005 Symptoms 9/12 after injection 35% lidocaine 30% articaine 30% prilocaine On the figures.we do not see a disproportionate involvement from articaine Pogrel, Danish Medicines Agency, 2008 Non surgical paraesthesias??? Study of referrals in Denmark appears to implicate articaine Some bias non returning patients classified as potentially permanent damage Fall in referrals after 2005 no real reason given Doesn t quote Pogrel 2007 Practical advice There is no restriction on use of articaine for inferior alveolar nerve blocks In UK defence organisations will support you if you use it In UK defence organisations will support you if you don t use it 4

5 20 % partial intra vasal injections Up to 80 fold increase of epinephrine levels Plasma concentration of tritium labeled epinephrine after intra oral injections in volunteers Local Anaesthesia in Germany administrations/year 90 % Articaine 4 %: Epinephrine 1: (~ 45 %) Epinephrine p 1: (~ 55 %) Side effects: 4,5 % 7 6,1 6 5 Anesth Prog, 4 3, p = 0,0411 % Regional Anaesthesia Articaine 200 ( n = 664 ) Articaine 100 ( n = 547 ) Aspiration Aspiration technique A vital step when injecting dental anaesthetic Why? Deposition of any anaesthetic into a blood vessel can result in systemic disturbances. Deposition of any anaesthetic into a blood vessel causes the solution to dissipates around the body; anaesthesia reduced Basic principle: To create a negative pressure in the cartridge liquid from the tissue at the deposition site is sucked up Before injecting : 1. Insert the needle 2. Aspirate by pulling plunger back, check for blood in cartridge, if so reposition the needle and try again. DON T INJECT UNLESS NEGATIVE! Standard Self-Aspirating Aspiration can be performed actively or passively with standard cartridges or passively with self aspirating cartridges. Manual Manual Aspiration Standard Cartridges Passive Aspiration System DENTSPLY Self Aspirating Cartridges Standard dental cartridges have a solid bung pierced by a barb or hook on the syringe plunger. Aspiration by manually pulling back the plunger to create negative pressure DISADVANTAGE: Risk of the needle moving during aspiration risk of false negative Self aspirating is a more reliable than manual aspiration No active movement from operator required Mechanism of the DENTSPLY Self Aspirating Cartridges (Astra type) Self aspiration cartridges have specially adapted bung, needing different syringe plunger Thin centre of the bung distended when pressure exerted. When force stopped the bung returns to usual shape negative pressure (aspiration) 5

6 Self aspirating mechanism (Astra type) Other aspirating systems Phentolamine mesylate (OraVerse) Nonselective -adrenergic blocking drug First therapeutic agent for reversal of soft-tissue tissue anaesthesia Median lip recovery times reduced by minutes Clinical use viewed favourably by dentists and patients No serious adverse events reported Percentage of patients reporting normal sensation 30 mins post PM injection Arch PM Sham Max Mand Tavares et al, J Am Dent Assoc 2008 Phentolamine mesylate (OraVerse) Costs $10-12 ( ) per 1.7ml cartridge The delivery systems years 1999 Prohibitive for routine use at present 6

7 Application of new technology The WAND Disposable handpiece Microprocessor The Wand CC Syringe Foot control Speed of Delivery Precision needle control pen grip Flow Rate? Clinical Relevance Direct positive correlation between pressure and pain exists in dentistry. Pressure direct positive correlation with flowrate. To decrease pain and anxiety of local anesthetic injection use pressure less then 306 mmhg (6 psi) in movable mucosa. A Correlation exists: Tissue Type and Exit-pressure 7

8 AMSA - anaesthetized area Pulpal Palatal Labial/Buccal Williams WP (1999) P-ASA - advantages P-ASA - anaesthetised area Single injection for multiple teeth Crosses midline Reduced dosage of anaesthetic No unwanted soft tissue anaesthesia Pulpal Palatal Labial *7 STA - System Single Tooth Anesthesia Petzer (2001) 8

9 The Formula = Local Anaesthesia + + = Local Anaesthesia Drug Delivery + + Anatomy = System Outcome Innovation Defines Our Future What is Oraqix? What is Oraqix? Oraqix 25/25 mg per g Periodontal Gel (2.5% lidocaine, 2.5% prilocaine) Same active ingredients as EMLA 2.5% lidocaine; 2.5% prilocaine Anaesthetic drugs in Xylocaine and Citanest, respectively White cream for skin anaesthesia Pre canulation Not licensed for dental use Oraqix Contained in a clear liquid Still 2.5% lidocaine; 2.5% prilocaine A liquid that sets as a gel at body temperature Oraqix is a POM (Prescription Only Medicine) Oraqix How do we use it? Licensed indications Oraqix is a non-injectable dental local anaesthetic indicated in adults for localised anaesthesia in periodontal pockets for diagnostic and treatment procedures such as probing, scaling and/or root planing 9

10 What is in the box? Supplied in 1.7g Glass cartridges Box of 20 cartridges Each cartridge is supplied with a blunt tip applicator Each cartridge 42.5mg lidocaine 42.5mg prilocaine Cartridges The air-bubble is larger than in injectable local anaesthetics, and does not pose a risk as Oraqix is not injected Cartridges Cartidges Oraqix should be a liquid when administered. If it has gelled, cool until becomes a liquid again. Visible air bubble moves when tilting cartridge Not labelled sterile Manufactured aseptically, like injectable anaesthetics Cartridge can be disinfected with 60% ethanol or 60-70% isopropanol wipes Unassembled Dispenser Inserting Cartridge 10

11 Bending Applicator Tip Ready for use Can be bent to aid access Bend using tip cover Do not bend at hub Application Application Depress paddle to dispense liquid Position of tip of applicator Applicator tip in gingival crevice / periodontal pocket Inject and move round tooth Effective in 30 seconds, Duration 20 minutes Sufficient in one cartridge to anaesthetise one quadrant Can be site specific Apply to two or three sites at a time Timings 11

12 Maximum dose Scaling Showing Removal Maximum dose is 5 cartridges in one treatment session Maximum dose cumulative if used with injectable local anaesthetics 10 patients Safety At least 16 teeth with pockets 4mm Application of Oraqix to all teeth (18-28) g SRP on 3 teeth. Maximum plasma levels detected min after application Lidocaine ( ng/ml) Prilocaine ( ng/ml) Initial signs of CNS-toxicity at 5000 ng/ml Plasma levels of lidocaine and prilocaine after application of Oraqix, a new intrapocket anesthetic, in patients with advanced periodontitis Friskopp J & Huledal G, J Clin Periodontol 2001 Duration and Onset 30 patients Oraqix applied and left for 30 seconds, 2 minutes and 5 minutes SRP on 2-3 teeth Pain assessment with Visual Analogue Scale (VAS; 100mm) and Verbal Rating Scale (VRS; 5 levels) Duration of anaesthesia probing using normal force 5 minutes intervals until sensation returned or 30 minutes after end of SRP Evaluation of side effects by follow-up phone call hours after SRP The anesthetic onset and duration of a new lidocaine/prilocain gel intra pocket anesthetic (Oraqix ) for periodontal scaling/root planing. Friskopp J et al., J Clin Periodontol 2001 Duration and Onset Results Visula Analogue Scale Time VAS (median) Duration (mean) 30 sec 7.5 mm 18.1 minutes 2 min 28.5 mm 17.3 minutes 5 min 15.5 mm 19.9 minutes VRS no patient severe or very severe pain no significant differences between groups Conclusion Oraqix provides anaesthesia after 30 seconds Duration of action minutes Efficacy 122 patients at 8 centres Oraqix or placebo - 30 seconds - 2 minutes, SRP on one quadrant. Patient discomfort second application of gel Discomfort continued classed as in need of a rescue anaesthesia (Injection) Measurements Pain assessment Visual Analogue Scale (VAS; 100mm) and Verbal Rating Scale (VRS; 5 levels) Need of a rescue anaesthesia Intrapocket Anesthesia for Scaling and Root Planing: Results of a Double Blind Multicenter Trial Using Lidocain Prilocaine Dental Gel Jeffcoat MK et al., J Periodontol

13 Efficacy Results VAS Oraqix : 7 mm Placebo: 17 mm (median) VAS significant reduction in reported pain. Mean reduction 8mm compared to placebo group (p < , Hodges-Lehmann estimate) VRS Oraqix : 90% of patients no pain or mild pain Placebo: 64% of patients no pain or mild pain Efficacy Results Rescue anaesthesia Oraqix : 11% of patients (7 of 63) Placebo: 17% of patients (10 of 59) Trend noted: higher efficacy in deeper pockets with more pronounced inflammation Efficacy in Pain Sensitive Patients 85 patients at 4 centres, VAS scores on probing greater than 30, Oraqix or placebo for seconds, SRP on one quadrant If the patient had any discomfort second application of gel If discomfort continued classed as in need of a rescue anaesthesia (Injection) Measurements Pain assessment with VAS 100 mm Pain assessment with VRS (5 levels) Need of a rescue anaesthesia Intrapocket Anesthesia for Scaling and Root Planing in Pain Sensitive Patients Magnusson I et al., J Periodontol 2003 Efficacy in Pain Sensitive Patients Results VAS Oraqix : 11 mm Placebo: 27 mm The VAS significant reduction in reported pain. Mean reduction of 10 mm vs placebo-group (p < 0.004, Hodges-Lehmann estimate) Results similar between centres VRS (p=0.003) Oraqix : 70% of the patients reported no pain or mild pain Placebo: 48% of the patients reported no pain or mild pain Efficacy in Pain Sensitive Patients Results Rescue anaesthesia Oraqix : 5% of the patients (2 of 43) Placebo: 17% of the patients (7 of 42) Trend noted: higher efficacy in deeper pockets with more pronounced inflammation Oraqix vs Infiltration Anaesthesia 175 patients, 8 centres Oraqix vs. Xylocaine 2% with Adrenaline Two treatment visits one week apart 2 quadrants one side Oraqix 2 quadrants other side injection Apple Newton Message Pad for evaluation by the patients Patient evaluation of a novel non injectable anesthetic gel a multicenter crossover study comparing the gel with infiltration anesthesia during scaling and root planing van Steenberge D et al., J Periodontol

14 Oraqix vs Infiltration Anaesthesia Results Satisfactory anaesthesia during SRP? (patient opinion) Gel (n=157) Injection (n=157) Very satisfactory 34% 51% Satisfactory 45% 45% Not completely 17% 4% satisfactory Unsatisfactory 3% 0 Preference of patients 70 % (110 of 157) patients preferred Oraqix 22 % (35 of 157) patients preferred the injection 8 % (12 of 157) patients had no preference Oraqix vs Infiltration Anaesthesia Results Reason for Patient Preference Gel (n=110) Injection (n=35) Less pain Less discomfort afterwards Less numbness 70 Absence of injection 35 Less apprehension re - 11 feeling pain Oraqix vs Infiltration Anaesthesia Results Ability to perform adequate treatment (investigator s opinion) Gel injection Very satisfactory 42% 83% Satisfactory 34% 17% Not completely 20% 0 satisfactory Unsatisfactory 4% 0 Review of Findings Flexible use Local, quadrant, arch, Safe in clinical use Rapid onset (30 seconds) Acceptable duration ~20 minutes Can be reapplied Review of Findings Good pain elimination Good patient comfort No injection No post operative soft tissue anaesthesia 70% of the patients preferred Oraqix to conventional anaesthesia Improved compliance with SRP treatments Summary Treat local with respect Reflective practice Patients appreciate efficacy Dislike postoperative numbness and injections Use LA appropriately and effectively 14

15 Thank you for your kind attention 15