to ensure successful pain relief , in - depth knowledge of local anesthetic solutions and appropriate application of local anesthetic techniques is mandatory .
the inferior alveolar nerve block is the most frequently used nerve block technique for anesthetizing mandibular teeth during endodontic procedures . in case of symptomatic irreversible pulpitis
the success rate of mandibular anesthesia with the inferior alveolar nerve block has been reported to vary from 38 - 85% .
previous studies have shown success rates of only 19 - 56% for inferior alveolar nerve blocks in patients with irreversible pulpitis .
it is evident from these studies that severely painful inflamed tooth is often difficult to manage conventionally and local anesthetic failure is a common occurrence .
these include periodontal ligament injection , intrapulpal injection , intraosseous injection , and intraseptal injection .
supplemental injections are essential in patients with irreversible pulpitis as the local anesthetic injections had an eight - fold higher failure rate compared to normal patients .
needleless device uses pressure to force the anesthetic solution safely into oral tissues . in needleless jet injection ,
the anesthetic solution is immediately taken up by the myelin sheath of the nerve with an onset of action of approximately 1 ms .
the x - tip intraosseous injection allows deposition of a local anesthetic solution directly into the cancellous bone adjacent to the tooth to be anesthetized .
success of these supplemental intraosseous injections in achieving pulpal anesthesia in patients with irreversible pulpitis has been reported to be 82 - 98% .
the intraosseous systems available commercially in the market include the stabident system ( fairfax dental inc . ,
miami ) , x - tip system ( x - tip technologies , dentsply , maillefer ) , intraflow ( intra vantage , plymouth , mn ) , and the quicksleeper ( dht , cholet , france ) .
clinical trial studies have been published using stabident , x - tip sytem , intra flow , and the quicksleeper system .
the x - tip anesthesia delivery system consists of a special hollow needle that serves as the drill and guide - sleeve component .
the drill leads the guide sleeve through the cortical plate after which it is separated and withdrawn .
the guide sleeve remains embedded in the bone and the anesthetic solution is delivered with the aid of a 27-gauge needle .
there has been a continual search for safer and more profound local anesthetic compounds for attaining adequate pulpal anesthesia .
articaine , classified as an amide anesthetic , has increased liposolubility and potency because of the presence of a thiophene ring .
greater diffusion of articaine anesthetic solution to the teeth can be attributed to increased liposolubility and smaller size of thiophene ring of articaine in contrast to benzene ring of lignocaine . according to some authors ,
ability of articaine to diffuse into the bone can produce pulpal anesthesia in mandibular teeth even after infiltration anesthesia .
clinical studies comparing the success rate of 4% articaine with that of 2% lignocaine have shown that 4% articaine was superior to 2% lignocaine as a general - purpose anesthetic .
the purpose of the study was to evaluate the anesthetic efficacy of x - tip intraosseous injection in patients with symptomatic irreversible pulpitis in mandibular posterior teeth , using 4% articaine with 1:100,000 adrenaline as local anesthetic when the conventional inferior alveolar nerve block proved ineffective .
the purpose of the study was to evaluate the anesthetic efficacy of x - tip intraosseous injection in patients with symptomatic irreversible pulpitis in mandibular posterior teeth , using 4% articaine with 1:100,000 adrenaline as local anesthetic when the conventional inferior alveolar nerve block proved ineffective .
thirty patients , 15 males and 15 females 15 - 53 years of age with a diagnosis of symptomatic irreversible pulpitis of mandibular posterior teeth were included in this study .
approval for the study was obtained from institutional ethical committee and written informed consent was acquired from each patient .
the diagnosis of irreversible pulpitis was confirmed by a chief complaint of spontaneous pain or pain at night , together with cold test and electric pulp testing showing an elevated and lingering pain response .
vitality of these teeth was first tested with cold pulp tester , dichlorodifluoromethane ( endo - frost , roeko , langenau , germany ) followed by electric pulp tester ( digitest pulp tester ) . in all 30 patients selected , control teeth showed normal response and the inflamed teeth showed an elevated and prolonged pain response to these tests .
inferior alveolar nerve block injection was administered using 1.7 ml of 4% articaine with 1:100,000 adrenaline ( septanest with adrenaline 1:100,000 , septodont , france ) with conventional long buccal injection . before commencing access preparation
, it was ensured that the control teeth did not respond to the maximum output of the electric pulp tester and the cold test .
the patients were instructed to rate any discomfort during access using a heft - parker visual analogue scale ( vas ) [ figure 1 ] . the vas scale consists of four categories .
mild pain was defined as greater than 0 mm and less than or equal to 54 mm .
supplemental intraosseous x - tip injection was administered in patients who had moderate or severe pain ( vas rating greater than 54 mm ) on access into dentin , when entering the pulp chamber or with initial file insertion .
heft - parker vas pain scale used for pain assessment the intraosseous injection with the x - tip system ( dentsply maillefer , usa ) was administered in the following manner : the perforation site was selected according to manufacturer 's instructions , 2 - 4 mm apical to alveolar crestal bone level in the attached gingiva , at a site distal or mesial to the operating tooth .
after determination of the perforation site , the perforator attached in micromotor handpiece was pushed through the attached gingiva until the x - tip contacted bone . after placing the drill at a 90 angle to the bone , the slow - speed air motor handpiece was activated and drilled at 90 to the bone . in 2 - 4 seconds , the drill perforated the cortical bone into the cancellous bone .
the handpiece was always activated while the perforator was within the bone to prevent breakage that might occur if the perforator was allowed to stop rotating .
after perforation , the drill was withdrawn from the guide sleeve , leaving the guide sleeve in place .
the 27-gauge ultrashort x - tip needle was inserted into the guide sleeve to its hub , and 1.7 ml of 4% articaine with 1:100,000 adrenaline ( septanest with adrenaline 1:100,000 , septodont , france ) was delivered over a 1-minute time period .
the success of the supplemental x - tip technique is defined as the ability to access the pulp chamber , place initial files , and instrument the tooth without pain ( vas score of zero ) or mild pain ( vas rating less than or equal to 54 mm ) .
if the patient had moderate to severe pain ( vas rating greater than 54 mm ) during access or initial instrumentation , the x - tip technique was considered as a failure and an intrapulpal injection was administered .
out of the 30 patients who participated in the study , 25 patients experienced no pain or mild pain and were counted as success .
five patients who experienced moderate to severe pain during access or initial instrumentation after intraosseous injections were considered a failure .
the various factors associated with anesthetic failure for conventional ian block include accessory innervations , accuracy of needle placement , anesthetic solution migration along the path of least resistance , tetrodotoxin - resistant class of sodium channels , which have been shown to be resistant to the action of local anesthetics , anxiety , psychological factors , and altered resting potentials and decreased excitability thresholds of nerves arising from inflamed tissue . owing to these myriad limiting factors , supplemental injections become necessary in cases when inferior alveolar nerve block is not effective in providing satisfactory anesthesia . in needle - phobic patients ,
the time of onset of action for pressure anesthesia was less when compared to classic needle infiltration but the total duration of anesthesia was more for needle infiltration anesthesia . it can be used for restorative procedures of short duration and direct pulp injections . in this study , the anesthetic success using x - tip intraosseous injection was 83.33% .
the results of this study shows that supplemental x - tip intraosseous injection helps in achieving successful pulpal anesthesia in patients with symptomatic irreversible pulpitis .
none of the x - tip perforators broke , and the onset of anesthesia was immediate .
the thickness of the cortical plate of posterior mandibular region condemns the use of infiltration injections .
the intraosseous injection overcomes this problem by allowing direct access to the cancellous bone via perforation of the cortical bone . in this study ,
this fact is critical , as higher the lipid solubility , the higher is the potency and better will be the diffusion through the medium into which it is injected , and therefore , the greater is its ability to cross the lipid membranes of the epineuria
this molecular configuration is subject to rapid hydrolysis by plasma cholinesterases after it is absorbed into the systemic circulation .
only the remaining 5 - 10% is subject to the slower , traditional hepatic metabolism .
the allergen paraminobenzoic acid ( paba ) , a frequent metabolite of ester metabolism , is not a by - product of the hydrolysis phase of articaine .
within the limitations of this study , we can conclude that when the inferior alveolar nerve block fails to provide profound pulpal anesthesia , the x - tip system using 4% articaine , was successful in achieving pulpal anesthesia in mandibular posterior teeth of patients presenting with irreversible pulpitis .
supplemental intraosseous injection with x - tip using 4% articaine with 1:100,000 adrenaline enabled soothing , swift , and sound anesthesia .
 introduction : pain management remains the utmost important qualifying criteria in minimizing patient agony and establishing a strong dentist  patient rapport . 
 symptomatic irreversible pulpitis is a painful condition necessitating immediate attention and supplemental anesthetic techniques are often resorted to in addition to conventional inferior alveolar nerve block.aim:the purpose of the study was to evaluate the anesthetic efficacy of x - tip intraosseous injection in patients with symptomatic irreversible pulpitis , in mandibular posterior teeth , using 4% articaine with 1:100,000 adrenaline as local anesthetic , when the conventional inferior alveolar nerve block proved ineffective.materials and methods : x - tip system was used to administer 1.7 ml of 4% articaine with 1:100,000 adrenaline in 30 patients diagnosed with irreversible pulpitis of mandibular posterior teeth with moderate to severe pain on endodontic access after administration of an inferior alveolar nerve block.results:the results of the study showed that 25 x - tip injections ( 83.33% ) were successful and 5 x - tip injections ( 16.66% ) were unsuccessful.conclusion:when the inferior alveolar nerve block fails to provide adequate pulpal anesthesia , x - tip system using 4% articaine with 1:100,000 adrenaline was successful in achieving pulpal anesthesia in patients with irreversible pulpitis . 