Local Complications PDF

290 PART III Techniques of Regional Anesthesia in Dentistry solutions into infected tissue because this may cause the infection to spread to uninvolved regions.4,5 Administration of local anesthetic solution into a site distant from the involved tooth is more likely to provide adequate pain contro...

290 PART III Techniques of Regional Anesthesia in Dentistry solutions into infected tissue because this may cause the infection to spread to uninvolved regions.4,5 Administration of local anesthetic solution into a site distant from the involved tooth is more likely to provide adequate pain control because of the existence of normal tissue conditions. Therefore regional nerve block anesthesia is a major factor in pain control for the pulpally involved tooth. Second, use a buffered local anesthetic solution. Administration of a solution of local anesthetic with a pH of approximately 7.4 increases the percentage of the RNH+ form approximately 6000-fold (lidocaine hydrochloride with epinephrine at pH 3.5 contains 0.004% RN and at pH 7.4 it contains 24.03% RN). In preliminary studies involving non–pulpally involved teeth, 71% of patients receiving a buffered local anesthetic achieved successful pulpal anesthesia within 2 minutes, versus 6 minutes 37 seconds for unbuffered local anesthetic.6 A number of clinical trials assessing the efficacy of buffered local anesthetics in mandibular teeth with symptomatic irreversible pulpitis (SIP) have been published.7-9 Unfortunately the results have not demonstrated significant increases in success. The subject of local anesthetic buffering is discussed in Chapter 20.␣ Methods of Achieving Anesthesia The following techniques are recommended for providing pain control in pulpally involved teeth: local infiltration, regional nerve block, intraosseous injection, intraseptal injection, periodontal ligament (PDL) injection, and intrapulpal injection. The use of buffered local anesthetics and the administration of articaine hydrochloride by infiltration in the mandible are also recommended. The order in which these techniques are discussed is the typical sequence in which, as per the author, they are normally used to achieve pain control when one seeks to extirpate pulpal tissues. Maxillary Teeth 1. Local infiltration (supraperiosteal injection). Local infiltration is commonly used to provide pulpal anesthesia in maxillary teeth. It is usually effective in endodontic procedures when severe inflammation or infection is not present. Local infiltration should not be attempted in a region where infection is obviously (clinically or radiographically) present because of the possible spread of infection to other regions and a greatly decreased rate of success. When infection is present, other techniques of pain control should be relied on. Infiltration anesthesia is often effective at subsequent endodontic visits if adequate débridement and shaping of the canals have been previously accomplished. The use of local anesthesia during subsequent visits, for débridement and shaping and filling of the canals is strongly recommended. Miles10 (a neurophysiologist) poignantly described the history of his endodontic experience in 1993. He describes his feelings during treatment subsequent to pulpal extirpation in Box 16.1. • BOX 16.1 Dental Pain: Self-Observations by a Neurophysiologist “It is worth noting this patient’s response to having his root canals instrumented with and without anesthesia. With full anesthesia, the author was quite relaxed and was aware only of a general vibratory sensation as the canals were reamed: doubtless this sensation was caused by bony transmission of the vibration to receptors located outside the range of the anesthetic block. However, at the second appointment, when reaming was resumed without anesthesia, this patient experienced several sharp jabs of pain when remnants of vital tissue were curetted away. This led to a feeling of acute apprehension for this stage of the procedure. Perhaps this apprehension was amplified by the patient’s knowledge that the tip of the reamer was approaching the apex, and that if (it) were inadvertently advanced by half a millimeter or so, the resulting sensation would be very painful sensation. It is possible, therefore, that this concern may then be less vivid to a lay patient. However, if this second stage of the endodontic procedure is regularly associated with pain, even if this consists only of a couple of brief jabs, it may be possible to ensure a pain-free experience without widespread anesthesia by slowly spinning local anesthetic down the root canal to a point just short of where the reamer evoked the pain. This possibility should be investigated. The point of this discussion is that a clinician is most likely to retain the patient’s confidence and cooperation by meticulous anesthesia at all stages of the procedure, particularly as a relaxed patient will also feel less pain.” 2. Regional nerve block. Regional nerve block anesthesia is recommended in cases where infiltration anesthesia may be ineffective or contraindicated. The techniques are discussed in detail in Chapter 13. Regional nerve block, the anterior superior alveolar (ASA), middle superior alveolar, posterior superior alveolar (PSA), anterior middle superior alveolar, and V2 block, is likely to be effective because the anesthetic solution is deposited at a distance from the inflammation, where tissue pH and other factors are more normal. 3. Articaine hydrochloride. Meta-analyses comparing lidocaine hydrochloride with articaine hydrochloride have shown articaine’s effectiveness by maxillary infiltration to be 3.81 times that of lidocaine.11 4. Buffered local anesthetic solution. Although clinical trials with the administration of buffered local anesthetic solutions in mandibular teeth with SIP have failed to demonstrate any significant advantage,7-9 the use of buffered local anesthetics—in almost all clinical situations, not only endodontics—is highly recommended by this author (see Chapter 20).12 5. Inhalation sedation. The use of inhalation sedation with nitrous oxide and oxygen (N2O-O2) is suggested for two reasons: (1) it allays a patient’s apprehension during what, in their mind at least, is a painful procedure and (2) N2O-O2 raises the pain reaction threshold of the patient, modulating their response to painful stimuli. Box 16.2 illustrates the recommended sequence for achieving pain control in pulpally involved maxillary teeth. CHAPTER 16 • BOX 16.2 Recommended Sequence for Achieving Pain Control in Maxillary Pulpally Involved Teeth Anesthetic Considerations in Dental Specialties 291 • BOX 16.3 Recommended Sequence for Achieving Pain Control in Pulpally Involved Mandibular Teeth at or Anterior to the Mental Foramen Infiltration Buffered local anesthetic solution Nerve block (PSA, MSA, ASA, V2) (Buffered) Articaine HCl Incisive nerve block (Buffered) Articaine infiltration at apex of mandibular Incisor tooth to be treated Inhalation sedation (N2O-O2) Achieving clinically adequate pain control for endodontic procedures in the maxillary arch is not as significant a challenge as it is in the mandible, particularly when molar teeth are involved.␣ Inhalation sedation (N2O-O2) • BOX 16.4 Soft tissue anesthesia is NEVER Mandibular Teeth 1. Use of buffered local anesthetic solutions for all injections (see Chapter 20). 2. Nerve block anesthesia—the inferior alveolar nerve block (IANB), Gow-Gates mandibular nerve block, VaziraniAkinosi closed-mouth mandibular nerve block, and incisive nerve block—is commonly used initially when one is seeking pulpal anesthesia for mandibular teeth. In most instances, it is successful in providing clinically adequate anesthesia permitting painless extirpation of the pulp tissues; however, in the presence of acute inflammation (e.g., SIP), success rates are significantly lower.13,14 3. Buccal infiltration of (buffered) articaine (0.6 to 0.9 mL) at the apex of tooth to be treated (see Chapter 20). Clinical trials in both mandibular posterior15 and anterior teeth16 have demonstrated the efficacy of articaine by mandibular infiltration.␣ Mandibular Teeth at or Anterior to the Mental Foramen 1. Incisive nerve block (see Chapter 14). Deposition of 0.6 mL of (buffered) local anesthetic solution outside the mental foramen and then application of firm digital pressure for minimally 1 minute, preferably 2 minutes, provides pulpal anesthesia to the mandibular premolars, canine, and incisor teeth with a high degree of success. a. When mandibular incisors are to be treated, the buccal infiltration of 0.6 to 0.9 mL of (buffered) articaine is recommended. Meechan16 has demonstrated its effectiveness (unbuffered articaine) in non–pulpally involved teeth. This should be done following IANB, Gow-Gates mandibular nerve block, Vazirani-Akinosi closed-mouth mandibular nerve block, or incisive nerve block as well. 2. Box 16.3 illustrates the recommended sequence for achieving pain control in pulpally involved mandibular teeth at or anterior to the mental foramen.␣ a guarantee of pulpal anesthesia Mandibular Molars In the presence of SIP, mandibular molars are the most difficult teeth to anesthetize effectively.17 In a survey of 121 dentists, Stiagailo17 reported that 55% encountered difficulty in achieving successful pulpal anesthesia “often” or “sometimes” in non–pulpally involved mandibular molars. When treating “exacerbated chronic pulpitis” or SIP, 69% and 74%, respectively, failed to achieve successful pulpal anesthesia “almost always” “often,” or “sometimes.” Click et al.18 reported that following a “successful” Gow-Gates mandibular nerve block—using the presence of lip anesthesia as a criterion for success—93% of patients had lip anesthesia, yet only 35% had successful pulpal anesthesia (Box 16.4). When infected mandibular molar teeth are being treated, it is recommended that steps 1, 2, and 3 in the section “Mandibular teeth”) be used initially. The question of what volume of local anesthetic should be administered by nerve block has been assessed in several clinical trials with conflicting results.19-21 Comparing 1.8 mL and 3.6 mL of 2% lidocaine with epinephrine 1:100,000, Fowler and Reader19 in 2013 concluded that “for patients presenting with irreversible pulpitis, success was not significantly different between a 3.6-mL volume and a 1.8-mL volume of 2% lidocaine with 1:100,000 epinephrine. The success rates (28% to 39%) with either volume were not high enough to ensure complete pulpal anesthesia.” In 2015 the same group reported that “the incidence of missed IANBs in asymptomatic patients was 6.3% for 1 cartridge (1.8 mL); and 3.8% for 2 cartridges (3.6 mL) lidocaine 1:100,000. The incidence of missed IANBs 292 PART III Techniques of Regional Anesthesia in Dentistry in SIP patients was 7.7% for 1 cartridge (1.8 mL); and 2.3% for 2 cartridges (3.6 mL) lidocaine 1:100,000.”20 Abazarpoor et al.21 using either 1.8 mL or 3.6 mL of 4% articaine with epinephrine 1:100,000 by IANB in SIP concluded that “3.6 mL articaine provided significantly higher success rate (77%) of IANBs compared with 1.8 mL of the same anesthetic solution (25.5%), although neither group had 100% successful anesthesia. Increasing the volume of articaine provided significantly higher success rates of IANBs in mandibular 1st molar teeth with SIP but did not result in 100% anesthetic success.” It is this authors recommendation that when one is seeking to extirpate the pulpal tissues of mandibular molars with SIP that a nerve block (step 2 above) be administered with 3.6 mL of, preferably, (buffered) 4% articaine with epinephrine 1:100,000. As important as the administration of inhalation sedation is for endodontic procedures in the maxilla (see step 5 in the section “Maxillary teeth”), its use during attempts at extirpating the pulpal tissues in mandibular molars with SIP is of greater importance. In comparing inhalation sedation with placebo (room air plus oxygen), Stanley et al.23 reported “the results showed that N2O-O2 sedation (30% to 50%) did increase the success of an IAN [inferior alveolar nerve] block (50% vs. 28% placebo) and therefore might be a useful technique to add to the armamentarium used in the treatment of teeth with symptomatic irreversible pulpitis (i.e., in addition to using supplemental anesthesia). Furthermore, if a patient were to present with irreversible pulpitis of a mandibular tooth and severe anxiety and requesting sedation, this study points to the possibility that N2O-O2 sedation might be preferable to oral sedation with triazolam. With N2O-O2 sedation the dose is titratable, the patient would not require a driver to accompany them, and they would not be sedated beyond the length of the treatment appointment. Studies with oral sedation concluded that “for mandibular posterior teeth, triazolam in a sublingual dose of 0.25 mg will not result in an increase in success of the IAN [inferior alveolar nerve] block in patients with irreversible pulpitis. When using conscious sedation, profound local anesthesia will still be required as the principal means of eliminating the sensation of pain during endodontic treatment in patients with irreversible pulpitis.”23 In the absence of anesthesia profound enough to permit painless access to the pulp chamber of mandibular teeth, the following techniques are recommended (intraosseous, intraseptal, and PDL injections can be used interchangeably): 1. Intraosseous injection. Intraosseous injection has experienced a resurgence of enthusiasm in recent years.24-32 Intraosseous injections can provide anesthesia profound enough to allow painless access to the pulp chamber for removal of pulpal tissue in most situations. The intraosseous technique is described in Chapter 15 and is reviewed here (Figs. 16.1 and 16.2): a. Apply topical anesthetic at the site of the injection to anesthetize the soft tissue. • Fig. 16.1 Stabident intraosseous injection technique. • Fig. 16.2 X-Tip intraosseous injection technique. b. While holding the perforator perpendicular to the cortical plate, gently push it through the attached gingiva until its tip rests against bone. c. Activate the handpiece and apply pressure on the perforator in a “pecking” motion until a sudden loss of resistance is felt. d. Withdraw the perforator and dispose of it safely. e. Insert the local anesthetic needle into the hole and deposit the volume of local anesthetic appropriate for the procedure (see Table 15.3). 2. Intraseptal injection. This is a variation of intraosseous and PDL injections and may be used as an alternative to these techniques. It is more successful in younger patients because of decreased bone density. Intraseptal anesthesia is described in Chapter 15 and proceeds as follows33: a. Anesthetize the soft tissues at the injection site via local infiltration. b. Insert a 27-gauge short needle into the intraseptal bone distal to the tooth to be anesthetized (Fig. 16.3). c. Advance the needle firmly into the cortical plate of bone. e. Inject about 0.2 mL of anesthetic. Considerable resistance must be encountered as the anesthetic is being deposited. If administration of the anesthetic is easy, the needle tip is most likely in soft tissue, not in bone. 3. PDL Injection. The PDL injection may be an effective method of providing anesthesia in pulpally involved teeth if infection and severe inflammation are not present. This technique is discussed in Chapter 15. A 27-gauge short needle is firmly placed between the interproximal bone and the tooth to be anesthetized. The bevel of the needle should face the tooth (although bevel orientation is not critical for success). It is appropriate to bend the needle CHAPTER 16 • Fig. 16.3 For the intraseptal injection, a 27-gauge short needle is inserted into the intraseptal bone distal to the tooth to be anesthetized. • Fig. 16.4 Intrapulpal injection. if necessary to gain access. A small volume (0.2 mL) of local anesthetic is deposited under pressure for each root of the tooth. It may be necessary to repeat the PDL injection on all four sides of the tooth. Computer-controlled local anesthetic delivery devices enable the PDL injection to be administered more successfully and more comfortably than an injection given with a traditional dental local anesthetic syringe. 4. Intrapulpal injection. In about 5% to 10% of mandibular posterior teeth with SIP, supplemental injections, even when repeated, do not produce profound anesthesia; pain persists when the pulp is entered. This is an indication for an intrapulpal injection.34 The intrapulpal injection provides pain control both by the pharmacologic action of the local anesthetic and by applied pressure. This technique may be used once the pulp chamber is exposed surgically or pathologically. The technique is described in Chapter 15 (Fig. 16.4). When intrapulpal injections are administered properly, a brief period of sensitivity, ranging from mild to severe, may accompany the injection.10 Clinical pain relief follows almost immediately, permitting instrumentation to proceed atraumatically. Anesthetic Considerations in Dental Specialties 293 With the growing popularity of intraosseous anesthesia, the need for intrapulpal injection to provide profound pain control in cases of irreversible pulpitis has decreased. Today there are but few occasions when all of the techniques discussed fail to provide clinically acceptable pain control, and intrapulpal anesthesia cannot be attempted until the pulp is exposed. The following sequence of treatment may be of value on these rare occasions: 1. Use slow-speed high-torque instrumentation (which usually is less traumatic than the high-speed low-torque option). 2. Use (minimal or moderate) sedation (which helps decrease the patient’s response to painful stimuli). N2OO2 inhalation sedation is a readily available, safe, and highly effective method of relaxing a patient and elevating his or her pain reaction threshold. 3. If, after the preceding steps, the pulp chamber is opened, administer direct intrapulpal anesthesia. This is usually effective despite the brief period of pain associated with intrapulpal administration. 4. If a high level of pain persists and it still is not possible to enter the pulp chamber, then the following sequence should be considered: a. Place a cotton pellet saturated with local anesthetic loosely on the pulpal floor of the tooth. b. Wait 30 seconds; then press the pellet more firmly into the dentinal tubules or the area of pulpal exposure. This area may be sensitive initially but should become insensitive within 2 to 3 minutes. c. Remove the pellet and continue use of the slow-speed drill until pulpal access is gained; then perform direct injection into the pulp. With most endodontic procedures, difficulty in providing adequate anesthesia occurs only at the initial appointment. Once the pulp tissue has been extirpated, the need for pulpal anesthesia disappears. Soft tissue anesthesia may be necessary at ensuing appointments for comfortable placement of the rubber dam clamp, but if adequate tooth structure remains, this may not be necessary. Some patients do respond unfavorably to instrumentation of their root canals, even following thorough débridement of the canals.10 If this occurs, infiltration with (buffered) articaine hydrochloride and/or local anesthetic administration into the root canal itself may be used. Apply a small amount of topical anesthetic ointment onto the file or reamer before inserting it into the canal. This helps desensitize the periapical tissues during instrumentation of the canals. As patients may react to filling of the canals, local anesthesia should be considered before this stage of treatment is started. Box 16.5 illustrates the recommended sequence for achieving pain control in pulpally involved mandibular molar teeth.␣ Pediatric Dentistry Pain control is one of the most important aspects of behavioral management in children undergoing dental treatment, yet the main reason children give for fear of going 294 PART III Techniques of Regional Anesthesia in Dentistry • BOX 16.5 Recommended Sequence for Achieving Pain Control in Pulpally Involved Mandibular Molar Teeth Buffered local anesthetic solution Nerve block (IANB, GGMNB, VA) with 2 cartridges of local anesthetic (Buffered) Articaine infiltration at apex of mandibular to be treated Inhalation sedation (N2O-O2) Intraosseous, intraseptal, or PDL Intrapulpal injection to the dentist is the fear of the injection.35 Anxiety is the biggest predictor of poor pain control.36 Unpleasant childhood experiences have made many adults acutely phobic with regard to dental treatment. Today, however, many local anesthetic drugs are available to make pain management relatively easy. Special concerns in pediatric dentistry relevant to local anesthetics include anesthetic overdose (toxic reaction), self-inflicted soft tissue injury related to the prolonged duration of soft tissue anesthesia, and technique variations related to the smaller skulls and differing anatomy of younger patients. Local Anesthetic Overdose Overdose from a drug occurs when the blood level in its target organ(s) becomes excessive (see Chapter 18). Undesirable effects resulting from overly high local anesthetic blood levels may be caused by intravascular injection or the administration of large volumes of the drug. Local anesthetic overdose (also known as toxicity) occurs when the blood level of the drug in the brain or myocardium—the target organs for local anesthetics—becomes too high. Therefore local anesthetic overdose relates to the volume of drug reaching the cerebrovascular and cardiovascular systems and to the blood volume of the patient. Once the blood level of a drug reaches overdose levels, the drug exerts unwanted and possibly deleterious systemic actions that are consistent with its pharmacologic properties. Local anesthetic overdose produces a progressive depression of the central nervous system and cardiovascular system, with reactions ranging from mild tremor to tonic-clonic convulsions (central nervous system), or from a slight decrease in blood pressure and cardiac output to cardiac arrest (cardiovascular system). Disproportionately high numbers of deaths and serious morbidities caused by local anesthetic overdose have occurred in children, leading to the assumption that local anesthetics are more toxic in children than in adults.37,38 This is untrue; it is the safety margin of local anesthetics in small children (e.g., lighter weight) that is lower than it is in adult. Given an equal dose of a local anesthetic, a healthy adult patient with a larger body weight and greater blood volume will have a lower blood level of anesthetic than of a child patient of lesser weight and smaller blood volume. Blood volume, to a large degree, relates to body weight: the greater the body weight, the greater the blood volume (except in cases of marked obesity). Maximum recommended doses (MRDs) of all drugs administered by injection should be calculated—before being administered—by body weight and should not be exceeded, unless it is absolutely essential to do so.38 For example, two cartridges of 3% mepivacaine (54 mg per cartridge) exceed the MRD for a 15-kg (33-lb) child of 66 mg. Unfortunately, lack of awareness of maximum doses has led to fatalities in children.39-43 The ease with which a lighterweight child may be overdosed with local anesthetics is compounded by the practice of multiple-quadrant dentistry and the concomitant use of sedative drugs (especially opioids).37 Chicka et al.,44 in reviewing malpractice insurance claims involving anesthesia for pediatric patients, found that 41% of the claims involved local anesthetic overdose. Of those claims, 43% occurred when local anesthetic was the only drug administered. When treating a smaller child, the dentist must maintain strict adherence to MRDs (Table 16.1) and should anesthetize only the one quadrant that is being treated at that time. In discussing MRDs, de Jong45 states “a word about ‘safe’ or ‘recommended’ local anesthetic doses, as found on drug package inserts or in reference books: These doses are best estimates, indirectly derived from experimental studies and clinical case reports. Generally, the upper limits tend to be on the safely conservative side of the fence. Considerably higher doses than ‘recommended’ can be (and have been) given if used judiciously. Conversely, the so-called safe dose may be a gross overdose if placed where not intended. In my (unpublished) experience, for instance, 10 mg lidocaine or 2.5 mg bupivacaine produced instant grand mal seizures when injected unintentionally into the vertebral artery. ‘Safe’ doses can thus be either too little or too much, depending on circumstances. VIGILANCE is the watchword!” Cheatham et al.46 surveyed 117 dentists who regularly treated children about their local anesthetic use. They found that the lighter the weight of the patient, the more likely the doctor was to administer an overly large dose of the local anesthetic, based on milligrams per kilogram of body weight. For example, a 13-kg (∼28.5-lb) patient should receive no more than 91 mg of lidocaine (based on an MRD of 7.0 mg/kg). The range of doses administered by dentists treating children was 0.9 to 19.3 mg/ kg. As the patient’s weight increased, the number of milligrams per pound or kilogram reached lower and safer levels, the maximum of the range falling to 12.6 mg/kg in the 20-kg (44-lb) patient and to 7.2 mg/kg in the 35-kg (77-lb) patient. The mean dose of local anesthetic also fell when the patient’s weight increased, from 5.4 mg/kg in the CHAPTER 16 Anesthetic Considerations in Dental Specialties 295 TABLE Maximum Recommended Doses of Local Anesthetics as per the US Food and Drug Administration 16.1 Dose Drug Formulation Food and Drug Administration Maximum Recommended Dose (mg) Articaine 4% with epinephrine None recommended 7.0 3.2 Lidocaine 2% with epinephrine 500 7.0 3.2 Mepivacaine 3% plain (no vasoconstrictor) 400 6.6 3.0 Mepivacaine 2% with levonordefrin 400 6.6 3.0 Prilocaine 4% plain (no vasoconstrictor) 600 8.0 3.6 Prilocaine 4% with epinephrine 600 8.0 3.6 Bupivacaine 0.5% with epinephrine None recommended None recommended 90 mg/kg mg/lb TABLE Local Anesthetic Administration by Dentists Who Treat Children (N = 117) 16.2 Patient Age (Years) 2 Mean Dose Range Weight (kg) mg mg/kg mg mg/kg 13 69.9 5.4 12–252 0.9–19.3 Maximum Recommended Dose (mg/kg) Lidocaine 7.0 Mepivacaine 6.6 5 20 96.5 4.8 18–252 0.9–12.6 10 35 135 3.8 36–252 1.0–7.2 Modified from Cheatham BD, Primosch RE, Courts FJ. A survey of local anesthetic usage in pediatric patients by Florida dentists. J Dent Child. 1992;59:401–407. 13-kg patient to 4.8 mg/kg in the 20-kg patient to 3.8 mg/ kg in the 35-kg patient (Table 16.2). Administration of large volumes of local anesthetic is not necessary when one seeks pain control in younger patients. Because of anatomic differences (see the following discussion in “Techniques of Local Anesthesia in Pediatric Dentistry”), smaller volumes of local anesthetics will provide the depth and duration of pain control usually necessary to successfully complete planned dental treatment in lighter-weight patients. Because all injectable local anesthetics are inherently vasodilators, leading to more rapid vascular uptake and a shorter duration of pulpal anesthesia, it is strongly recommended that a vasoconstrictor be included in the local anesthetic solution unless there is a compelling reason for it to be excluded.47 Many treatment appointments in pediatric dentistry do not exceed 30 minutes in duration; therefore the use of a vasoconstrictor-containing local anesthetic is considered unnecessary and unwarranted. It is thought that increased duration of soft tissue anesthesia, especially after IANB, increases the risk of self-inflicted soft tissue injury. A non–vasoconstrictorcontaining local anesthetic is frequently used (most often 3% mepivacaine). Providing 20 to 40 minutes of pulpal anesthesia, mepivacaine (3%) is considered the appropriate drug for this group of patients. This is true, provided that the dental treatment is confined to one quadrant per visit. However, when multiple quadrants are to be treated (and receive local anesthesia) on a smaller, lighter-weight patient in a single visit, administration of a “plain” drug into multiple injection sites increases the potential risk of overdose. Use of a local anesthetic containing a vasoconstrictor is strongly recommended whenever multiple quadrants are anesthetized in the smaller pediatric patient. In a 1992 survey, 69% of doctors treating children administered lidocaine with epinephrine as their primary anesthetic (Table 16.3).46 With the introduction of articaine hydrochloride in the United States (June 2000), a more recent survey (2012) of local anesthetic use among general and pediatric dentists showed that lidocaine 2% with epinephrine remains the preferred drug for approximately 77% but that articaine 4% with epinephrine is making inroads, with about 17% reporting it to be their preferred local anesthetic in children.47 Interestingly, 16% of general dentists and 10% of pediatric dentists listed articaine as their preferred local anesthetic in patients aged 2 to 3 years, even though the administration of articaine is not recommended in patients younger than 4 years.49 Wright et al.50 in a retrospective study of local anesthesia records in two pediatric dental offices found a total of 211 patients under 4 years of age who received a total of 240 doses of articaine. No adverse systemic adverse reactions were noted in the records or known to the clinicians. 296 PART III Techniques of Regional Anesthesia in Dentistry Factors increasing the risk of local anesthetic overdosage in younger patients are presented in Box 16.6.51␣ Complications of Local Anesthesia Self-inflicted soft tissue injury—accidental biting or chewing of the lip, tongue, or cheek—is a complication associated TABLE Local Anesthetic Choice by Dentists Who 16.3 Treat Children (N = 117) Percentage Using the Formulation Anesthetic Formulation 2% lidocaine + epinephrine 1:100,000 69 3% mepivacaine 11 2% lidocaine 8 2% mepivacaine + levonordefrin 1:20,000 8 Other anesthetics 4 Modified from Cheatham BD, Primosch RE, Courts FJ. A survey of local anesthetic usage in pediatric patients by Florida dentists. J Dent Child. 1992;59:401–407. • BOX 16.6 Factors Adding to Increased Risk of Local Anesthetic Overdose in Younger Patients 1. Treatment plan: all four quadrants treated using local anesthetic in one visit 2. Local anesthetic administered is a plain (no vasopressor) solution 3. Full cartridges (1.8 mL) administered with each injection 4. Local anesthetic administered to all four quadrants at one time 5. Exceeding the maximum dose based on patient’s body weight with residual soft tissue anesthesia (Fig. 16.5). Soft tissue anesthesia lasts considerably longer than pulpal anesthesia and may persist for 4 hours or more after local anesthetic administration. Fortunately, most patients do not encounter problems related to prolonged soft tissue anesthesia, but most of those who do are younger, the oldest old (>85 years), or mentally or physically disabled patients. Problems related to soft tissue anesthesia most often involve the lower lip. Much less frequently, the tongue is injured, and rarely, the upper lip is involved. College et al.52 reported an 18% incidence of selfinflicted soft tissue injury in patients younger than 4 years receiving IANB. From 4 to 7 years, the rate was 16%, from 8 to 11 years, it was 13%, and from 12 years on, it was 7%. Several preventive measures can be implemented: 1. Select a local anesthetic with a duration of action appropriate for the length of the planned procedure. Some local anesthetics provide pulpal anesthesia of adequate duration (20 to 40 minutes) for restorative procedures in children, with a relatively short duration of soft tissue anesthesia (1 to 3 hours, instead of 4 or 5 hours) (Table 16.4). It should be kept in mind, however, that investigators have not demonstrated a relationship between the use of plain local anesthetics and a reduction in soft tissue trauma. The clinician must consider the advisability of using a local anesthetic containing a vasoconstrictor when treating multiple quadrants in view of the decreased margin of safety of local anesthetics in smaller children. 2. Administer phentolamine mesylate (OraVerse) at the conclusion of the traumatic portion of the dental procedure. Discussed more completely in Chapter 20, phentolamine mesylate is an α-adrenergic antagonist that, when injected into the site where local anesthetic with a vasoconstrictor was previously deposited, produces vasodilation, increasing blood flow through the area, thereby increasing the speed with which the local anesthetic drug diffuses away from the injection site and out of the nerve. The duration of residual soft tissue anesthesia is significantly reduced. Phentolamine mesylate has been B A • Fig. 16.5 Lip trauma caused by biting while the area was anesthetized. CHAPTER 16 approved by the Food and Drug Administration for use in patients aged 3 years or older.53,54 3. Advise both the patient and the accompanying adult about the possibility of injury if the patient bites, sucks, or chews on the lips, tongue, or cheeks, or ingests hot substances while anesthesia persists. These instructions are given with the parent/guardian present. 4. Some doctors reinforce the verbal warning to the patient and the adult by placing a cotton roll in the mucobuccal fold (held in position by dental floss through the teeth) if soft tissue anesthesia is still present at the time of the patient’s discharge. 5. A sticker, reminding the child not to bite or suck on his/ her lip/cheek or tongue, can be placed on the child’s shirt on the same side as the anesthetized lip or tongue. Management of self-inflicted soft tissue trauma consists of reassuring the patient, allowing time for anesthetic effects to diminish, and coating the involved area with a lubricant (petroleum jelly) to help prevent drying, cracking, and pain.␣ Techniques of Local Anesthesia in Pediatric Dentistry Local anesthetic techniques used in children do not differ greatly from those in adults. However, the skulls of children do have some anatomic differences from those of adults. For instance, maxillary and mandibular bone in children is generally less dense, which works to the dentist’s advantage (Fig. 16.6). Decreased bone density allows more rapid and complete diffusion of the anesthetic solution. Also, children are smaller; thus standard injection techniques can usually can be completed with decreased depth of needle penetration and a smaller volume of local anesthetic. Anesthetic Considerations in Dental Specialties 297 needle should be used and the depth of needle penetration should be modified to meet the smaller dimensions of the pediatric patient, to minimize the risk of overinsertion leading to hematoma. As an alternative to the PSA nerve block, Rood55 has suggested using buccal infiltrations on both the mesial and distal aspects of the maxillary first molar to avoid a prominent zygomatic process. The ASA nerve block also can be used in children, as long as it is realized that the depth of penetration is probably just slightly greater than with a supraperiosteal injection (because of the lesser height of the maxillae in children). As supraperiosteal infiltration has a very high success rate, there are few indications for the PSA or ASA nerve block in very young children. Occasionally a maxillary tooth remains sensitive after a supraperiosteal injection because of accessory innervation from the palatal nerves56 or widely flared palatal roots. Palatal anesthesia can be achieved in children through the nasopalatine and greater (anterior) palatine nerve blocks. The technique for a nasopalatine nerve block proceeds exactly as described in Chapter 13. That for a greater palatine nerve block is as follows: The administrator visualizes a line from the gingival border of the most posterior molar that has erupted to the midline. The needle is inserted from the opposite side of the mouth, distal to the last molar, bisecting this line. If the child has only primary dentition, the needle is inserted approximately 10 mm posterior to the distal surface of the second primary molar, bisecting the line drawn toward the midline. An intrapapillary injection can also be used to achieve palatal anesthesia in young children. Once buccal anesthesia Maxillary Anesthesia All primary teeth and permanent molars can be anesthetized by supraperiosteal infiltration in the mucobuccal fold. The PSA nerve block is rarely necessary because of the effectiveness of infiltration in children. However, in some individuals, the morphology of the bone surrounding the apex of the permanent first molar does not permit effective infiltration of local anesthetic because the zygomatic process lies closer to the alveolar bone in children. A PSA nerve block may be warranted in this clinical situation. A 27-gauge short dental 10 8 6 1 2 7 3 11 9 4 5 12 11 6 7 9 10 8 TABLE Relative Durations of Pulpal and Soft Tissue 16.4 Anesthesia Drug Approximate Duration of Pulpal Anesthesia (min) Approximate Duration of Soft Tissue Anesthesia (h) Mepivacaine, plain 20–40 3–4 Prilocaine, plain 10 (infiltration) 1.5–2 • Fig. 16.6 Upper and lower jaws in a 4-year-old child with erupted primary teeth and unerupted permanent teeth. 1, First (central) incisor of primary dentition; 2, second (lateral) incisor of primary dentition; 3, canine of primary dentition; 4, first molar of primary dentition; 5, second molar of primary dentition; 6, first (central) incisor of permanent dentition; 7, second (lateral) incisor of permanent dentition; 8, canine of permanent dentition; 9, first premolar of permanent dentition; 10, second premolar of permanent dentition; 11, first molar of permanent dentition; 12, second molar of permanent dentition. (From Abrahams PH, Marks SC Jr, Hutchings RT. McMinn’s color atlas of human anatomy. 5th ed. St Louis: Mosby; 2003.) 298 PART III Techniques of Regional Anesthesia in Dentistry is effective, the needle (27-gauge short needle) is inserted horizontally into the buccal papilla just above the interdental septum. Local anesthetic is injected as the needle is advanced toward the palatal side. This should cause ischemia of the soft tissue.57␣ Mandibular Anesthesia Supraperiosteal infiltration is usually effective in providing pain control in mandibular primary teeth.58-60 Sharaf58 reported that buccal infiltration anesthesia in the mandible in 80 children (aged 3 to 9 years) was as effective as IANB in all situations, except when pulpotomy was performed on the primary second molar. This was the result of decreased density of bone in the mandible in younger children. The success rate of mandibular infiltration anesthesia decreases somewhat for primary mandibular molars as the child becomes older. The technique of supraperiosteal infiltration in the mandible is the same as in the maxilla. The tip of the needle is directed toward the apex of the tooth, in the mucobuccal fold, and approximately one-fourth to one-third of a cartridge (0.45 to 0.6 mL) is slowly deposited. The IANB has a greater success rate in children than in adults because of the location of the mandibular foramen. The mandibular foramen in children lies distal and more inferior to the occlusal plane. Benham61 demonstrated that the mandibular foramen lies at the height of the occlusal plane in children and extends an average of 7.4 mm above the occlusal plane in adults. He also found that there is no age-related difference as to the anteroposterior position of the foramen on the ramus. The technique for an IANB is essentially identical for adults and children. The syringe barrel is placed in the corner of the mouth on the opposite side. The average depth of penetration to bone is approximately 15 mm, although this may vary significantly with the size of the mandible and the age of the patient. As with the adult, bone should be contacted before any solution is deposited. In general, the more inferior location of the mandibular foramen in children provides a greater opportunity for successful anesthesia. “Too low” injections are more likely to be successful. In clinical situations the success rate for well-behaved children usually exceeds 90% to 95%. Because of the decreased thickness of soft tissue overlying the inferior alveolar nerve (about 15 mm), a 25- or 27-gauge short needle may be recommended for the IANB in younger, smaller patients. This should be changed to a long needle once the patient is of sufficient size that a short needle does not reach the injection site without entering tissue almost to its hub. The buccal nerve may be anesthetized if anesthesia of the buccal tissues in the permanent molar region is necessary. The needle tip is placed distal and buccal to the most posterior tooth in the arch. Approximately 0.2 to 0.3 mL of solution is deposited. The Vazirani-Akinosi and Gow-Gates mandibular nerve blocks can also be used in children. Akinosi62 advocates the use of short needles with this technique in children. He states that the technique appears less reliable in children, which he relates to the difficulty of judging the depth of penetration necessary in a growing child. The Gow-Gates mandibular nerve block can be used successfully in children.63 However, such injections are rarely necessary in pediatric dentistry because of the effectiveness of mandibular infiltration (when the dentition is composed entirely of primary teeth) and the relative ease with which one can achieve IANB and incisive nerve block. The incisive nerve block provides pulpal anesthesia for the five primary mandibular teeth in a quadrant. Deposition of anesthetic solution outside the mental foramen with application of finger pressure for 2 minutes provides a very high degree of success. The mental foramen is usually located between the two primary mandibular molars. A volume of 0.45 mL (one-fourth of a cartridge) is suggested in younger patients. The PDL injection has been well accepted in pediatric dentistry and can be used as an alternative to supraperiosteal injection. It provides the doctor with the means to achieve anesthesia of proper depth and duration on one tooth, without unwanted residual soft tissue anesthesia. The PDL injection is also useful when a child has discrete carious lesions in multiple quadrants. See Chapter 15 for a complete discussion of the technique for the PDL injection. It is recommended that the described technique be scrupulously adhered to, to avoid physiologic (pain) and psychological (fear) trauma to the patient.␣ Local Anesthetic Selection in Pediatric Dentistry The use of the long-duration local anesthetic bupivacaine (0.5%) with epinephrine 1:200,000 is rarely indicated in younger pediatric patients. The extended duration of soft tissue anesthesia (approximately 9 to 12 hours following nerve block techniques) associated with its administration increases the risk of self-inflicted soft tissue injury substantially. Short-duration local anesthetic solutions (e.g., 3% mepivacaine, 4% prilocaine without a vasoconstrictor) are excellent selections when the planned dental procedure is limited to but one quadrant in the appointment. Intermediate-duration local anesthetics are most commonly used when two or more quadrants of treatment are scheduled and/or when more invasive procedures are contemplated (e.g., pulpotomy).␣ Periodontics Special requirements for local anesthesia in periodontal procedures center on the use of vasoconstrictors to provide hemostasis and the use of long-duration local anesthetics for postoperative pain control. Postsurgical pain management, including the use of long-duration anesthesia in combination with nonsteroidal antiinflammatory drugs (NSAIDs), is discussed as a separate subject later in this chapter. CHAPTER 16 Soft tissue manipulation and surgical procedures are associated with hemorrhage, especially when the tissues involved are not healthy. Administration of local anesthetics without vasoconstrictors is counterproductive because the vasodilating property of the local anesthetic increases bleeding in the region of the injection.64 Vasoconstrictors are added to counteract this undesirable property of local anesthetics. The pharmacology of vasoconstrictors is more completely discussed in Chapter 3. As a review, vasoconstrictors produce arterial smooth muscle contraction through direct stimulation of α receptors located in the wall of the blood vessel. Consequently, it follows that local anesthetics with vasoconstrictors used for hemostasis must be injected directly into the region where the bleeding is to occur. Pain control for periodontal procedures should be achieved through nerve block techniques, including posterior superior alveolar nerve block, IANB, and infraorbital nerve block. Saadoun33 has shown that the intraseptal technique is very effective for periodontal flap surgical procedures. It decreases the total volume of administered anesthetic and the volume of blood lost during the procedure. Local anesthetic solutions used for nerve blocks should include a vasoconstrictor in a concentration not greater than 1:100,000 for epinephrine or 1:20,000 for levonordefrin. An epinephrine concentration of 1:50,000 is not recommended for pain control because depth, duration, and success rates are no greater than those seen with anesthetics containing epinephrine 1:100,000 or 1:200,000. Epinephrine is the drug of choice for local hemostasis. Norepinephrine (which is not available in North America in dental local anesthetics but is available in some other countries) can produce marked ischemia, which can lead to tissue necrosis and sloughing. Norepinephrine is not recommended for use in hemostasis.65,66 Epinephrine is most commonly used for hemostasis in a concentration of 1:50,000 (0.2 mg/mL). Generally, small volumes (not exceeding 0.1 mL) are deposited when used for hemostasis. Epinephrine also provides excellent hemostasis in a concentration of 1:100,000, although surgical bleeding is inversely proportional to the concentration of vasoconstrictor administered. When a “plain” local anesthetic is infiltrated (e.g., 3% mepivacaine) during periodontal surgery, blood loss is two to three times that noted when 2% lidocaine with epinephrine 1:100,000 is administered.67 Buckley et al.68 demonstrated that use of a 1:50,000 epinephrine concentration produced a 50% decrease in bleeding during periodontal surgery from that seen with a 1:100,000 concentration (with 2% lidocaine). However, epinephrine is a drug with systemic effects and some undesirable local effects. Studies have shown that even the small volumes of epinephrine used in dentistry can significantly increase the concentrations of plasma catecholamine and can alter cardiac function.69 Therefore it is prudent to administer the smallest volume of the least concentrated form of epinephrine that provides clinically effective hemostasis. Moore et al.70 compared the hemostatic efficacy of 4% articaine with epinephrine 1:100,000 Anesthetic Considerations in Dental Specialties 299 and 4% articaine with epinephrine 1:200,000 during periodontal surgery. Significant differences were found between 4% articaine with epinephrine 1:100,000 and 4% articaine with epinephrine 1:200,000 in the surgeons’ ability to visualize the surgical field. Surgeons rated the surgical field as “clear” 83.3% of tine time with 4% articaine with epinephrine 1:100,000 and 59.5% of the time with 4% articaine with epinephrine 1:200,000 (P = .008). Additionally, the volume of blood loss was 54.9 mL (± 36.0 mL) for 4% articaine with epinephrine 1:100,000 and 70.2 mL (±53.0 mL) for 4% articaine with epinephrine 1:200,000 (P = .018). They concluded that although both 4% articaine with epinephrine 1:100,000 and 4% articaine with epinephrine 1:200,000 provided excellent surgical pain control, 4% articaine with epinephrine 1:100,000 had the additional therapeutic advantage of providing better visualization of the surgical field and less bleeding. As tissue levels of epinephrine decrease after its injection for hemostasis, a rebound vasodilation develops. Sveen.67 demonstrated that postsurgical bleeding (at 6 hours) occurred in 13 of 16 patients (81.25%) receiving 2% lidocaine with epinephrine for surgical removal of a third molar, whereas none of 16 patients who underwent surgery with 3% mepivacaine bled at 6 hours after surgery. Bleeding interfered with postoperative healing in 9 of 16 patients (56.25%) receiving lidocaine with epinephrine, compared with 25% of patients receiving no epinephrine. Evidence also suggests that the use of epinephrine in local anesthetics during surgery may produce an increase in postoperative pain.71 Many doctors use a 30-gauge short needle to deposit anesthetics for hemostasis. Their rationale is that the thinner needle produces a smaller defect (puncture) in the tissue. If a small puncture is important, then a 30-gauge needle should be used, but only for this purpose (hemostasis). A 30-gauge short needle should not be used if there is the possibility of positive aspiration of blood, or if any depth of soft tissue must be penetrated. Aspiration of blood through a 30-gauge needle is difficult (although possible).72 A 27-gauge needle can be used for local infiltration to achieve hemostasis when vascularity is a problem, or in any other area of the oral cavity without an increase in patient discomfort.␣ Oral and Maxillofacial Surgery Pain control during surgical procedures is achieved through administration of local anesthetics, given alone or in combination with inhalation sedation, intravenous sedation, or general anesthesia. As is the case with periodontal surgery, long-duration local anesthetics play an important role in postoperative pain control and are discussed separately. Local anesthetic techniques used in oral surgery do not differ from those used in nonsurgical procedures. Therefore it should be expected that instances of partial or incomplete anesthesia will occur. Oral and maxillofacial surgeons frequently treat patients who have received 300 PART III Techniques of Regional Anesthesia in Dentistry intravenous sedation or general anesthesia before the start of surgery. These techniques act to modify the patient’s reaction to, and memory of, pain, leading to a decrease in the number of reported instances of inadequate local anesthesia. Local anesthesia is routinely administered to patients undergoing general anesthesia for third molar extractions. The reasons for this are: 1. General anesthesia does not prevent pain. General anesthesia prevents the patient from responding outwardly to painful stimulation. Blood pressure, heart rate, and respiratory rate respond to surgical stimulation (they increase). 2. Pain control through local anesthetic administration during surgery permits less exposure to general anesthetic agents, allowing a faster postanesthetic recovery and minimizing drug-related complications. 3. Hemostasis is possible if a vasoconstrictor is included. 4. Residual local anesthesia in the postoperative period aids in postsurgical pain control. The volume of drug and the rate at which it is administered are important in all areas of dental practice but are probably most important during extraction of teeth from multiple quadrants. When four third molars are extracted, effective pain control must be obtained in all four quadrants. This requires multiple injections of local anesthetics, which usually occur within a relatively short time. Four cartridges or more of local anesthetic are frequently administered.a The rate at which these local anesthetics is administered must be closely monitored to lessen the occurrence of complications. Complications arising from rapid administration of local anesthetic include any of the following: 1. increased pain during injection 2. increased risk of a serious overdose reaction if the local anesthetic is administered intravascularly (the speed of intravascular drug administration significantly affects the clinical manifestations of toxicity) 3. postanesthetic pain caused by tissue trauma during the injection These complications and their prevention, recognition, and management are discussed in greater detail in Chapters 17 and 18. In some persons the inferoposterior border of the mandible is not innervated by the trigeminal nerve. Any of the mandibular nerve blocks described in Chapter 14 provide only partial anesthesia in this situation. The PDL or a Typical local anesthetic injections for extraction of four third molars include: 1. right and left inferior alveolar nerve blocks, 1.8 mL for each (3.6 mL) 2. right and left posterior superior alveolar nerve blocks or supraperiosteal infiltration over each third molar, 1.3 to 1.8 mL for each (2.6 to 3.6 mL) 3. right and left palatal infiltration over the maxillary third molars, 0.45 mL for each, or right and left greater palatine nerve block, 0.45 mL for each (0.09 mL) Total volume of local anesthetic: 8.1 mL or 162 mg for a 2% solution, 243 mg for a 3% solution, or 324 mg for a 4% solution. • Fig. 16.7 Extensive treatment area in fixed prosthodontics requires administration of nerve blocks as opposed to infiltration. (Photograph courtesy Dr. Terry Donovan.) intraosseous injection (see Chapter 15) usually corrects the lack of pain control in this circumstance.␣ Fixed Prosthodontics When preparing a tooth for full coverage (crown or bridge), it is necessary to place a provisional restoration over the prepared tooth. Although achieving pain control might not be difficult at the initial visit, it may be difficult at subsequent visits to adequately anesthetize the prepared tooth. The reason for this is probably the provisional restoration. Overly high restorations produce traumatic occlusion, which can lead to considerable sensitivity after about 1 day. Poorly adapted gingival margins develop microleakage, also causing sensitivity. Preparation of the tooth itself can cause sensitivity, through desiccation of tooth structure, possible pulpal involvement, and periodontal irritation. The longer these sources of irritation are present, the greater the trauma to the tooth is likely to be, and the more difficult it is to achieve adequate anesthesia. Usually a regional nerve block is effective. Supraperiosteal injections generally do not provide adequate pain control in these situations (depth may be adequate, but duration is considerably shorter than that usually expected from the drug). One additional consideration in fixed prosthodontics occurs when a large case (e.g., full arch) is being prepared in the maxilla (Fig. 16.7). It commonly takes a considerable length of time to prepare multiple teeth, pack two cords around each tooth, make impressions, and prepare provisional restorations. Anesthesia (infiltration) commonly does not last as long as with a mandibular block technique. Use of maxillary nerve blocks, such as PSA, ASA, and V2 nerve blocks, is recommended (see Chapter 13).␣ Long-Duration Local Anesthesia Prolonged Dental or Surgical Procedures Several specialty areas of dental practice require longerthan-usual pulpal and soft tissue anesthesia. These include fixed prosthodontics, oral surgery, and periodontics. During CHAPTER 16 longer procedures (2 hours or more) an adequate duration of pulpal anesthesia may be difficult to achieve with more commonly used anesthetics such as articaine, lidocaine, mepivacaine, and prilocaine. Bupivacaine is a long-acting local anesthetic that can then be used. It is discussed more completely in Chapter 4. Bupivacaine, a homologue of mepivacaine, has a long duration of clinical effectiveness when used for regional nerve block. Its duration of action when administered by supraperiosteal injection, although still long, is somewhat shorter (shorter even than that of lidocaine with epinephrine).73 Its postoperative analgesic period lasts an average of 8 to 9 hours in the mandible and more than 5 hours in the maxilla following nerve block. Bupivacaine is available with a vasoconstrictor (epinephrine 1:200,000). It is interesting to note that the addition of a vasoconstrictor to bupivacaine does not prolong its duration of action.74␣ Postsurgical Management of Pain Frequently, after extensive surgical procedures, patients experience intense pain when the local anesthetic effect dissipates. It was, and still is in many cases, common practice to treat postsurgical pain through administration of opioid analgesics. However, opioids have a high incidence of undesirable side effects, such as nausea, vomiting, constipation, respiratory depression, and postural hypotension, especially in ambulatory patients.75 Addiction to opioids, the so-called opioid epidemic, is yet another reason to avoid their use following dental surgery.76 Additionally, opioid analgesics are not very effective in the management of pain following dental surgery.77 Long-acting local anesthetics administered by nerve block to surgical patients offer a means of providing successful postoperative pain control with minimal risk of developing adverse reactions. An advantage of using longduration local anesthetics is their longer postoperative analgesia, which leads to a reduced need for the administration of postoperative opioid analgesic drugs.78 Dentists often use an intermediate-acting local anesthetic such as articaine, lidocaine, mepivacaine, or prilocaine with a vasoconstrictor for the surgical procedure, administering a long-acting local anesthetic just prior to the completion of the surgery. Danielsson et al.73 compared bupivacaine, etidocaine, and lidocaine with regard to their effects on postoperative pain, and found that both bupivacaine and etidocaine were more effective in controlling postoperative pain when compared with lidocaine. They also reported that bupivacaine was more effective than etidocaine in providing postoperative analgesia, and that patients receiving bupivacaine used significantly fewer analgesics. It is pertinent to note that there appears to be a difference between etidocaine and bupivacaine with respect to their ability to provide adequate hemostasis, even though they contain the same concentration of a vasoconstrictor (1:200,000). Danielsson et al.74 noted that bupivacaine provided adequate Anesthetic Considerations in Dental Specialties 301 hemostasis in 90% but that etidocaine provided adequate hemostasis in only 75% of procedures. It is possible that a higher concentration of local anesthetic may necessitate a higher concentration of a vasoconstrictor to provide comparable hemostasis. Also keep in mind the different vasodilating properties of the solutions.79 Etidocaine hydrochloride is not available in dental cartridges in North America. Protocol for Perioperative and Postoperative Pain Control in Surgical Patients Postoperative pain associated with most uncomplicated dental surgical procedures is mild and is well managed by oral administration of NSAIDs such as aspirin and ibuprofen.77 Preoperative administration of NSAIDs appears to delay the onset of postoperative pain and to lessen its severity.78,80 When a patient is unable to tolerate aspirin or other NSAIDs, acetaminophen can provide acceptable analgesia.77 Other dental surgical procedures, such as removal of bony impactions and osseous periodontal or endodontic surgery, are more trau