Anestezie Pentru Endodontie

Please download to get full document.

View again

of 8
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Information Report

School Work


Views: 10 | Pages: 8

Extension: PDF | Download: 0

Related documents
  Colleagues  for     Excellence Published for the Dental Professional Community by the  American Association of Endodontists  Winter 2009 Taking the Pain out of Restorative Dentistryand Endodontics: Current Thoughtsand Treatment Options to Help Patients Achieve Profound Anesthesia Endodontics Cover artwork: Rusty Jones, MediVisuals, Inc.  his newsletter is intended to help resolve some o the misunderstandings surrounding local anesthesia and outline newmethods and ideas or local anesthetic administration rom a specialist’s perspective. The goal is to help general prac-titioners achieve successul pulpal anesthesia. Discussion will ocus on the inerior alveolar nerve block, as most clinicalproblems occur with this commonly used block.Just like implants, endodontics and restorative dentistry, the subject o local anesthesia has enjoyed an explosion o knowledge. Proven techniques and evidence-based research oer a sound oundation or helping patients achieve prooundpulpal anesthesia. A good deal o the new research on local anesthesia has come rom endodontists, published in the highlyrespected  Journal of Endodontics, and provides a welcome insight into the problems associated with local anesthesia. En-dodontists are the resource o choice or practitioners seeking answers about providing proound local anesthesia becausethey deal with pulpal anesthesia and pain management on a daily basis. Use of the Inferior Alveolar Nerve Block Following are some common misunderstandings associated with the use o this block: 1. Lip numbness indicates pulpal anesthesia. Not really. We were all taught that i the lip is numb, the teeth are numb. However, a number o studies (1-12) have ound lipnumbness means the lip is numb, but it does not guarantee pulpal anesthesia! It does mean the block injection was accurateenough to anesthetize the nerve fbers that supply the lip. Failure to achieve lip numbness occurs about 5% o the time withexperienced clinicians (11,12).  2. Sot tissue “sticks” indicate pulpal anesthesia. Unortunately, like lip numbness, mucosal sticks with a sharp explorer can’t be used to indicate pulpal anesthesia (1-3). 3. Lack o an accurate inerior alveolar nerve block injection causes anesthesia ailure. No. Studies using ultrasound (4) and radiographs (13,14) to accurately locate the inerior alveolar neurovascular bundleor mandibular oramen revealed accurate needle location did not guarantee successul pulpal anesthesia. One importantfact you want to remember is that even though proound lip anesthesia is achieved, patients do not always achieve pulpalanesthesia, but it is NOT the ault o the clinician or giving an inaccurate injection! 4. Once lip numbness is obtained, pulpal anesthesia is not ar behind. Not always. The onset o lip numbness occurs usually within 5-9 minutes o injection (1-3) and pulpal anesthesia usually oc-curs by 15-16 minutes (1-3). However, pulpal anesthesia may be delayed. Slow onset o pulpal anesthesia (ater 15 minutes)occurs approximately 19-27% o the time in mandibular teeth (6) and approximately 8% o patients have onset ater 30minutes (1-6,15). 5. Incorrect needle bevel orientation causes ailure. Not really. The orientation o the needle bevel (away or toward the mandibular ramus) or an inerior alveolar nerve blockdoes not aect anesthetic success or ailure (7). 6. Failure in molars and incisor teeth is the same. No. Pulpal anesthesia ailure occurs in approximately 17% o rst molars, 11% o rst premolars and 32% o lateral incisors(1-6). Again, 100% o these patients had proound lip numbness. Thereore, ailure o pulpal anesthesia is higher in the inci-sor teeth than the molars and premolars. 7. Accessory innervation is the main reason or ailure. No. Judging rom clinical and anatomical studies (16,17), the mylohyoid nerve is theaccessory nerve most oten cited as a cause or ailure with mandibular anesthesia.When the inerior alveolar nerve block was compared to a combination injection o the inerior alveolar nerve block plus the mylohyoid nerve block (Figure 1), whichwas aided by the use o a peripheral nerve stimulator, the mylohyoid injection didnot signicantly enhance pulpal anesthesia o the inerior alveolar nerve block (Fig-ure 2)(8). Another study employed the use o a lingual inltration o the rst molarater an inerior alveolar nerve block, but it did not signicantly increase success inthe mandible over the inerior alveolar nerve block alone (9). Endodontics:   Colleagues  for     Excellence 2  T Fig. 1.Injection site for the mylohyoid nerve block.  Thereore, the mylohyoid nerve is not a major actor in ailure with the inerior alveolar nerve block. Other nerves(buccal, lingual, cervical plexus) have been cited or ailure; however, the magnitude o ailure with the inerior alveolarnerve block is very dicult to explain by accessory innervation as a major contributor. 8. Cross innervation causes the majority o ailures in mandibular incisor teeth. Not really. Cross innervation does occur in mandibular central and lateral incisors (10,18). However, cross innervation is notthe major reason or ailure in incisor teeth—it is the ailure o the inerior alveolar nerve block to adequately anesthetizethese teeth. Administering bilateral inerior alveolar nerve blocks does not anesthetize the central and lateral incisors (10). 9. Giving another inerior alveolar nerve block will help the patient i they eel pain during operative procedures. Not really.   I the patient has profound lip numbness and experiences pain upon treatment, repeating the inerior alveolarnerve block does not help! Clinicians may think that another injection is helpul because the patient sometimes achievespulpal anesthesia ater the second injection. However, the patient may just be experiencing slow onset o pulpal anesthe-sia. That is, the second injection does not provide additional anesthesia—the frst injection is just “catching up” (6).  10. Two cartridges are better than one. No. Increasing the volume to two cartridges (Figure 3) o lidocaine (1,6,19) or increasing the epinephrine concentrationrom 1:100,000 to 1:50,000 (20, 21) will not provide better pulpal anesthesia. Endodontics:   Colleagues  for     Excellence 3  Continued on p. 4 Fig. 2.Pulpal anesthesia [no patient response at the highest reading (an 80 reading) with an electric pulp tester] ofthe first mandibular molar comparing the combination mylohyoid infiltration plus the inferior alveolar nerve block tothe inferior alveolar nerve block alone. No statistical differences were found. 0255075100     P   e   r   c   e   n   t   a   g   e   o    f    8    0    R   e   a    d    i   n   g   s Time (Minutes) 1 9 17 25 33 41 49 57   Mylohyoid + Inferior Alveolar Nerve BlockInferior Alveolar Nerve Block  Fig. 3.Pulpal anesthesia [no patient response at the highest reading (an 80 reading) with an electric pulp tester] ofthe first mandibular molar comparing 3.6 mL and 1.8 mL of 2% lidocaine with 1:100,000 epinephrine. No statisticaldifferences were found.   0255075100     P   e   r   c   e   n   t   a   g   e   o    f    8    0    R   e   a    d    i   n   g   s Time (Minutes) 19172533414957  1.8 ml of 2% Lidocaine with 1:100,000 epi.3.6 ml of 2% Lidocaine with 1:100,000 epi.  11. Plain 3% mepivacaine (Carbocaine) and 4% prilocaine (Citanest) solutions won’t work or an inerior alveolar nerve block. A cartridge o either mepivacaine or prilocaine will work the same as 2% lidocaine with epinephrine or pulpal anesthesiao at least 50-55 minutes (2). Clinically, this is an important nding because when medical conditions or drug therapies sug-gest caution in administering epinephrine-containing solutions, plain solutions can be used as an alternative or the inerioralveolar nerve block. 12. Articaine is better than lidocaine. Not really. Repeated clinical trials have ailed to demonstrate any statistical superiority o articaine over lidocaine or nerveblocks (12,22-24). 13. Articaine causes paresthesia and should not be used or nerve blocks. Questionable. Two retrospective studies ound a higher incidence o paresthesia with articaine and prilocaine (25,26). How-ever, it was a clinically rare event (14 cases out o 11 million injections). Pogrel (27) evaluated patients reerred with adiagnosis o damage to the inerior alveolar and/or lingual nerve, which could only have resulted rom an inerior alveolarnerve block. He ound 35% were caused by a lidocaine ormulation and 30% were caused by an articaine ormulation. Heconcluded there was not a disproportionate nerve involvement rom articaine. Why Don’t Patients Achieve Pulpal Anesthesia With the Inferior Alveolar Nerve Block? The central core theory may be our best explanation (28,29). It states nerves on theoutside o the nerve bundle supply molar teeth, and nerves on the inside supply inci-sor teeth (Figure 4). The anesthetic solution may not diuse into the nerve trunk toreach all nerves and produce an adequate nerve block. The theory may explain thehigher ailure rates in incisor teeth with the inerior alveolar nerve block (1-6). Proven Methods and Ideas to HelpWith Pulpal Anesthesia in Restorative Dentistry Evaluate Pulpal Anesthesia Beore Starting Treatment  Clinically, ollowing lip numbness, application o a cold rerigerant (Figure 5) or theelectric pulp tester can be used to test the tooth under treatment or pulpal anesthe-sia prior to beginning a clinical procedure (30-32). A cold rerigerant is easier to usethan an electric pulp tester. To test the tooth, simply pick up a large cotton pellet withcotton tweezers, spray the pellet with the cold rerigerant and place it on the tooth. I the patient responds, we have to consider using supplemental injections to achieve proound pulpalanesthesia. Thereore, ollowing an inerior alveolar nerve block and achieving lip numbness, wecan now determine i the patient is numb before starting our treatment. Note: I the patient is ex-periencing irreversible pulpitis, no patient response to cold testing may not always indicate pulpalanesthesia (32). Patients who have had previous difculty with achieving anesthesia may experience more ailures. Patients who report a history o previous diculty with anesthesia are more likely to experienceunsuccessul anesthesia (33). A good clinical practice is to ask the patient i they have had previousdiculty achieving clinical anesthesia. I they have had these experiences, supplemental injectionsshould be considered. A slow inerior alveolar nerve block injection (60 seconds) results in a higher success rate o pulpal anesthesia than a rapid injection (15 seconds). Yes, this is true (34). There is also less pain with the slow injection (34). Endodontics:   Colleagues  for     Excellence 4  Fig. 4.Central Core Theory. The axons in themantle bundle supply the molar teeth and thosein the core bundle supply the incisor teeth. Thelocal anesthetic solution diffuses from the mantleto the core. (Modified from DeJong RH: Local Anesthetics, St. Louis, 1994, Mosby). Fig. 5.A cold refrigerant canbe used to test for pulpalanesthesia before the start ofa clinical procedure.
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!