Commonly used drugs and dental materials 










275
Chapter11
Commonly used drugs
and dental materials
Local anaesthetics 276
Analgesics and sedatives 278
Antimicrobials 280
Dental materials 282
Miscellaneous drugs 284

276
CHAPTER11 Drugs and dental materials
276
Local anaesthetics
Getting good anaesthesia is the key to stress- free procedures.
The administration technique may be more important than product
selection (see E pp. 220–2), but you should be well informed about
the drug you areusing.
LA used for dental administration is typically of higher concentration
than that used for non- dental reasons in order to limit the volume.
Vasoconstrictor reduces the dose further; without it, the duration of
action may be tooshort.
LA is presented in 1.8 mL or 2.2 mL cartridges compatible with dental
syringes and can be used outside the oral cavity except in extremities
such as the nose tip and ear. Although some surgeons will disagree with
this it is safer to avoid vasoconstrictors in extremities.
Safe dosages
Arough estimate of one cartridge of 2% solution per 10kg body weight
will keep you well below the toxicdose.
This should give sucient anaesthesia in most cases. If not, think about
reasons for failure.
If two cartridges have not had sucient eect, consider using a dierent
preparation.
For children, a rule of thumb is 1– 2 cartridges in those <5years, up to
3 cartridges for those<10years, and 4 cartridges for children >10years,
although manufacturers recommend that the dose is calculated by
weight for eachchild.
Preparations
The commonly used injectable preparations are shown in Table 11.1. In prac-
tice, 2% lidocaine with 1:80,000 adrenaline is the most widely used solution.
However, bupivacaine and articaine can be very eective where longer- lasting
anaesthesia is required. There have been reports of neurotoxicity using these
higher- concentration solutions, so nerve block is not recommended.
Toxicity
The most common cause of toxicity is inadvertent IV injection so always
aspirate rst. Signs include:
disturbed taste, circumoral tingling (not reliable signs in our
patients!), confusion, dizziness, drowsiness, and tting
arrhythmia with i/ d BP depending on whether adrenaline has
beenused.
Management is airway maintenance and control of tting until the eect
of the LA has worno.

You're Reading a Preview

Become a DentistryKey membership for Full access and enjoy Unlimited articles

Become membership

If you are a member. Log in here

Was this article helpful?

275 Chapter11Commonly used drugs and dental materialsLocal anaesthetics 276Analgesics and sedatives 278Antimicrobials 280Dental materials 282Miscellaneous drugs 284 276CHAPTER11 Drugs and dental materials276Local anaestheticsGetting good anaesthesia is the key to stress- free procedures.• The administration technique may be more important than product selection (see E pp. 220–2), but you should be well informed about the drug you areusing.• LA used for dental administration is typically of higher concentration than that used for non- dental reasons in order to limit the volume. Vasoconstrictor reduces the dose further; without it, the duration of action may be tooshort.• LA is presented in 1.8 mL or 2.2 mL cartridges compatible with dental syringes and can be used outside the oral cavity except in extremities such as the nose tip and ear. Although some surgeons will disagree with this it is safer to avoid vasoconstrictors in extremities.Safe dosages• Arough estimate of one cartridge of 2% solution per 10kg body weight will keep you well below the toxicdose.• This should give sucient anaesthesia in most cases. If not, think about reasons for failure.• If two cartridges have not had sucient eect, consider using a dierent preparation.• For children, a rule of thumb is 1– 2 cartridges in those <5years, up to 3 cartridges for those<10years, and 4 cartridges for children >10years, although manufacturers recommend that the dose is calculated by weight for eachchild.PreparationsThe commonly used injectable preparations are shown in Table 11.1. In prac-tice, 2% lidocaine with 1:80,000 adrenaline is the most widely used solution. However, bupivacaine and articaine can be very eective where longer- lasting anaesthesia is required. There have been reports of neurotoxicity using these higher- concentration solutions, so nerve block is not recommended.Toxicity• The most common cause of toxicity is inadvertent IV injection so always aspirate rst. Signs include:• disturbed taste, circumoral tingling (not reliable signs in our patients!), confusion, dizziness, drowsiness, and tting• arrhythmia with i/ d BP depending on whether adrenaline has beenused.• Management is airway maintenance and control of tting until the eect of the LA has worno. LOCAL ANAESTHETICS277 AllergyAllergy to LA is extremely rare. The allergen maybe:• preservative (e.g. metabisulphite) in which case preservative- free preparations are available• latex used in the rubberbung.Most patients who have a bad experience with LA have done so because it is not properly administered or for psychological reasons.1Table11.1 Commonly used dental local anaesthetics Lidocaine Articaine Mepivacaine PrilocaineTrade name Xylocaine®Lignospan Special®Septocaine®Septanest®Scandonest L®Citanest®Concentration 1%2%4% 2%3% (plain)3%4% (plain)Vasoconstrictor 1:80,000 adrenaline1:100,000 or 1:200,000 adrenaline1:200,000 adrenaline1:20,000 levonordefrin1:1,850,00felypressin(Octapressin®)Maximum recommended dose (with vasoconstrictor)7 mg/ kg(11 cartridges for 70kg adult)7 mg/ kg 7 mg/ kg 8 mg/ kg<10 mL recommendedDuration of action (with vasoconstrictor)45 min 60 min 60– 100 min 45 min0 Neuro toxicity possible. Avoid using for nerve blockMethaemo-globinaemia reported in overdose.Avoid in pregnancy1 Rood JP (2000). Adverse reaction to dental local anaesthetic injection– ‘allergy’ is not the cause. Br Dental J 189:380– 4. 278CHAPTER11 Drugs and dental materials278Analgesics and sedativesDental pain can be excruciating— think of Tom Hanks self- extracting a tooth in the lm Castaway. In contrast, pain is often well tolerated in patients with facial fractures and after facial surgery. Discomfort from postoperative swelling may be improved by early use of steroids.Sustained tooth pain, irreversible pulpitis, will require some sort of proce-dure to remove the infected tissue, either root canal therapy or extraction of the tooth. Likewise, abscesses will usually require surgical intervention.Achieving good anaesthesia during procedures such as surgical extraction will reduce postoperative analgesic requirements. Long- acting anaesthetics such as Marcaine® are recommended for this reason.There are a few pain conditions aecting the head, such as trigeminal neuralgia, which require specialized treatment (see E p. 150).Topical analgesics• Lidocaine 5%– benzocaine 20% ointment— apply to the buccal sulcus for 2– 3min before injecting LA (see E pp. 220–2).• Benzydamine mouth rinse can be used for painful ulcerative conditions and radiation mucositis (see E pp. 248–9, and pp. 250–1).• Benzocaine lozenges are also useful for the above- listed conditions.Oral analgesics• NSAIDs have been shown to be eective as both analgesics and anti- inammatories following dentoalveolar surgery.• Ibuprofen is an excellent postoperative analgesic for simple and surgical extractions. Up to 400 mg four times daily is regularly prescribed forpain.• Paracetamol— studies have shown paracetamol to be eective after surgical wisdom tooth removal. Combine with ibuprofen for better eect.• Diclofenac sodium— 50 mg three times daily PO or PR is useful after major surgery. Often contra-indicated in asthma, peptic ulcer disease.• Opiates— patients undergoing major surgery should have PRN morphine sulfate solution considered. Co- codamol 30/ 500 or dihydrocodeine are commonly prescribed postoperatively.• Carbamazepine— this is not an analgesic but nonetheless is used to control pain in trigeminal neuralgia. 300 mg three times daily is increased up to a maximum of 2.4 g or until analgesia is achieved.• Gabapentin and pregabalin– these are second- line treatments for chronic and complex pain often best prescribed by a pain specialist.• Tricyclic and other selective antidepressants such as uoxetine have an important role in the management of atypical facialpain. ANALGESICS AND SEDATIVES279 Sedatives• Diazepam— dental anxiety is not uncommon and some patients may require a small dose of benzodiazepine as pre- procedure anxiolysis. Diazepam 5 mg the night before and on the morning of the appointment will produce a mild sedative eect. Patients will require an escort and should not drive if this regimen isused.• Alternatively, temazepam, a shorter- acting drug, can be given 1 hour before surgery at a dose of 10– 30 mg, depending on weight, alcohol tolerance, and eect.• Midazolam— this is the drug of choice for operator- controlled conscious sedation. It gives an excellent anxiolytic and amnesic eect but is not analgesic so LA must also beused.• Check that the patient has an escort before starting.• Check medical history and consent.• Check that a suitably trained assistant is available (specialist sedation trained nurses).• Pulse oximetry is mandatory throughout. BP must be checked before starting.• Site cannula in forearm. Give a 2 mg bolus over 90 seconds (halve this for elderly patients).• Wait for 90 seconds before giving further 1 mg boluses until adequate sedation is achieved (patient should be drowsy but able to follow commands). It is unusual to need more than10mg.• Further boluses can be given during the procedure.• The patient must stay in the department until a trained sta member deems that they have fully recovered.• You must have the reversal agent (umazenil) available when using midazolam, but be aware that it has a shorter half- life than mida-zolam and administration may need to be repeated.• Nitrous oxide (N2O)— inhalational sedation is widely used in dentistry, particularly paediatric dentistry. N2O is delivered via a nasal mask to produce relative analgesia. LA must still beused.• Check consent, and that escort and assistant are available.• Contraindicated in nasal obstruction and rst trimester of pregnancy.• Start with 100% O2. Add 10% N2O for 1 minute and then increase to 20% for 1 min. Increase N2O by 5% every minute until adequately sedated (usual range 20– 50%).• Recover with 100% O2 and slowly raise up to sitting.• N2O may cause circumoral paraesthesia and is a drug open to abuse! Long- term exposure can cause a wide range of neurological eects. 280CHAPTER11 Drugs and dental materials280Antimicrobials• Odontogenic infections are polymicrobial and often anaerobic. Penicillins are still often eective.• The latest NICE guidelines2 state that antibiotic prophylaxis against endocarditis during dental procedures is not indicated.• Antibiotics should not be a substitute for pulp extirpation, tooth extraction, or pus drainage.• In severe infections where the airway is or could become compromised, antibiotics are denitely not a substitute (see E pp. 108–10,p. 263).AntibacterialThe indications for commonly used antibiotics are listed as follows. Where possible, swabs should be taken for sensitivity before starting, but in the mouth causative organisms can be dicult to isolate from normal oralora.• Amoxicillin— 500 mg three times daily for standard postoperative prophylaxis (e.g. after oro- antral communication). Up to 500 mg three times daily in oral infections. Co- amoxiclav 375 mg three times daily is also a good choice. Remember that co-amoxiclav is a penicillin (it has been given to penicllin allergy patients resulting in anaphylaxis!).• Metronidazole— 400 mg three times daily orally/ 500 mg three times daily IV. Combine with a penicillin for dental infection or after fracture communicating with the mouth or sinuses (alveolar fractures are open fractures). Beware warfarin.• Benzylpenicillin— IV penicillin for dental infections and fractures.• Erythromycin— used for penicillin- allergic patients.• Clindamycin— for osteomyelitis.• Chlorhexidine 0.2% mouthwash— eective for general disinfection of the mouth. Part of the standard postoperative protocol when intra- oral wounds have been made. It is not a substitute for tooth brushing. Long- term use can cause reversible staining ofteeth.• Tetracycline— avoid using this in children under 12 as it causes permanent staining of theteeth.• Flucloxacillin— 250– 500 mg four times daily for skin/ soft tissue infections.AntifungalOral candidal infection is common, particularly in the very young, the elderly, denture wearers, the immunocompromised, and the mal- nourished. As this is a large proportion of hospital inpatients, Candida should be at the top of your list when reviewing patients with sore mouths (see E pp. 246–7). Remembering a small list of drugs will be a greathelp.2 National Institute for Health and Care Excellence (NICE) (2008, updated 2016). Prophylaxis Against Infective Endocarditis: Antimicrobial Prophylaxis Against Infective Endocarditis in Adults and Children Undergoing Interventional Procedures. Clinical Guideline [CG64]. London: NICE. M https:// www.nice.org.uk/ guidance/ CG64 ANTIMICROBIALS281 • Nystatin suspension— 100,000 units (1 mL) held in mouth four timesdaily.• Miconazole gel 2%— apply 5– 10 mL four times daily to oral mucosa aftermeals.• Fluconazole— 50 mg capsules once daily for severe infections (+ topical treatment).AntiviralPrimary HSV infection (herpetic gingivostomatitis) can be extremely painful and the patient (usually a child) may be quite unwell. Herpes zoster reacti-vation as shingles, particularly when aecting the ophthalmic division of CN V or causing CN VII palsy (Ramsay Hunt syndrome) also requires prompt treatment.• Aciclovir 200 mg orally ve times daily (can be increased in severe cases). Achild needs half the adult dose. Topical treatment is available for herpes labialis (cold sore)— aciclovir cream (5% aciclovir).• If the ophthalmic division of the trigeminal nerve is aected, request an ophthalmology opinion, as associated dendritic corneal ulceration can cause lasting damage if not seen and treatedearly.• The Scottish Dental Clinical Eectiveness Programme has useful guidelines for prescribing for common dental conditions.33 Scottish Dental Clinical Eectiveness Programme. Published Guidance. M http:// www.sdcep.org.uk/ published- guidance/ 282CHAPTER11 Drugs and dental materials282Dental materialsThe dental armamentarium contains hundreds of materials with new prod-ucts constantly appearing. A few materials are regularly used in OMFS practice.• 2 Get someone to show you where the materials are kept and how to mix/ apply them before you need to usethem.• 2 Dentists in practice do not work alone and neither should you. Get someone to assistyou.Some useful materials are listedbelow.Dressings• Ledermix®—corticosteroid– antibiotic dressing paste applied directly to inamed pulps. Particularly useful where LA is ineective due to infection. Cover over with a temporary lling material and prescribe antibiotics if indicated.• Alvogyl®– brous dressing used to pack a dry socket (see E p. 226). Its eects are antimicrobial and analgesic. Do not decontaminate the whole pot by using a dirty instrument to dispensesome.• Whitehead’s varnish— iodoform- based resin that is used to pack large cavities (e.g. after bone cyst removal). The dressing is antiseptic and can be changed at regular intervals to check healing.Temporary lling materials• There are a number of zinc oxide and eugenol- based materials such as IRM®, Kalzinol®, and Cavit®.• They come as a paste and powder which are mixed beforeuse.• You should be able to form a rm ‘sausage’ which you can roll between your ngers before packing it in the tooth. Press down with a damp cotton roll or pledget to condense.• Can last for up to 2weeks.Filling and bonding materialsComposite• Tooth- coloured lling material which is useful for splinting teeth (see E p. 231). It comes in a variety of shades in premixedtubes.• The tooth is prepared with an acid etch and bonding agent for a strong bond to form but this may be omitted if it is just a temporary measure.• Composite is sensitive to water contamination, so the tooth must be dry. Use cotton rolls to keep tongue and cheeksaway.• Command set is activated by blue light (don’t forget to protect eyes) which polymerizes the material hard within 40 seconds.Glass ionomer cement(GIC)• Tooth- coloured lling material. It comes as a powder and liquid for hand mixing or in a capsule that needs high- speed mixing.• Auseful material for retrograde lling of a root canal in apicectomy and for cementing appliances toteeth. DENTAL MATERIALS283 Dental amalgamWatch out for the following:• Amalgam tattoo— inadvertent implantation into mucosa. May be confused with a pigmented lesion (see E p. 253).• Lichenoid reaction— white patches on the mucosa adjacent to the lling (see E pp. 250–1).• Streak artefacts— shine from the metal can make interpretation of CT dicult.• Inadvertent damage to a large amalgam restoration in the tooth adjacent to your extraction. Cover over with a temporary lling material and ask the GDP to replace.• Mercury poisoning— there is no evidence that mercury released from amalgam llings causes systemic illness.  BDA guidelines state that amalgam is safe to use and that sound llings should not be removed.4Impression materialsFor technique, see E p. 239.• Alginate— seaweed- derived hydrocolloid which does not taste unpleasant and is easy to work with. Accuracy is not as good as that of other materials. The powder is mixed with tap water. Working time is short so move quickly. Alginate will dry out and deform, so it must be wrapped in damp paper towels and sent to the laboratory straight away to be poured up as a plaster model (ideally within 1hour).• Elastomers— these can be polyethers, polysulphides, or silicones. They are very accurate, so they are used to construct close- tting appliances such as obturators. This can also make them dicult to remove from the mouth! They are quite stable and so do not need to be poured immediately (store dry). They are usually premixed and machine dispensed. Some are retarded by latex, so check rst before handling with glovedhands.Miscellaneous• Gutta percha— naturally occurring radio- opaque rubber, which is used to ll the canal space after root canal therapy. Gutta percha is produced as very ne points and is ideally suited to inserting into a sinus tract to locate its origin radiographically.• Coe- Pak®— a periodontal dressing which is used to protect healing tissue or for splinting. Mixed from two tubes of paste, you must use petroleum jelly on your gloves and patient’s lips before handling otherwise it will stick where you don’t wantitto!4 British Dental Association. Amalgam. M http:// www.bda.org/ dentists/ policy- research/ bda- policies/ public- health/ fact- les/ amalgam.aspx 284CHAPTER11 Drugs and dental materials284MiscellaneousdrugsBotulinumtoxinCommercially produced botulinum neurotoxin prevents release of acetyl-choline at the neuromuscular junction, preventing muscle movement. There are a number of dierent products and dose varies according to the type used and the anatomical region. Its eects last for around 3months and 2 weeks are required for the full eect to be seen following injection. In the UK, it is licensed for glabellar wrinkles and chronic migraine but it also has many unlicensed uses including drooling, Frey syndrome (gustatory sweat-ing), and blepharospasm.TranexamicacidThis antibrinolytic drug is available in oral and IV forms. It has been shown to be eective in reducing bleeding during trauma and surgery, and can be particularly useful in those with bleeding disorders. Dose will need to be adjusted in renal impairment. In OMFS it is commonly used during ortho-gnathic (particularly maxillary) surgery and in bleeding following extractions.Pentoxifylline and tocopherol (vitaminE)This drug combination has been used to treat osteoradionecrosis. The aims of treatment are to improve blood ow to damaged tissue and prevent ongoing free radical damage. Although reports have been encouraging, fur-ther research into this area is awaited.ChlorhexidineThis is frequently used as skin prep and as a mouthwash. It is particularly eective as a mouthwash because it binds to the tooth surface and has a bacteriostatic eect. In higher concentrations it is bactericidal and is used as a skin preparation to prevent postoperative wound infection.

Related Articles

Leave A Comment?