**5. Supplemental anesthesia techniques**

These techniques include intraosseous, intrapulpal, intraseptal and intraligamentary methods.

**1. Intraosseous technique:** This is done through a special tool such as X-TIP. The advantages of this method are rapid onset (less than 30 seconds), mild side effects, without the numbness of the lips and tongue and an atraumatic technique. Contraindications for this method are infection and severe inflammation at the injection area. In this technique, first, a point is recorded distal to the teeth in 2 mm apical to confluence of two lines consisting of a horizontal line from the gingival margin and a vertical line from the interdental papillae. The perforation of the soft tissue and bone is done at this point and the anesthetic drug is injected into the cancellous bone. In this method, depending on the number of teeth ¼ to 1 cartridge is used for the anesthesia. Vasoconstrictors should not be used except where required. The duration of pulpal anesthesia in this technique will be from 15 to 30 minutes [1].Sixon's study in 2008 revealed the effectiveness of this technique as a primary technique. For a total of 181 children and adults, 225 intraosseous injections were done with 4% articaine. The success of this technique was reported to be 95% for primary teeth and 87.9% for permanent teeth and it was shown that the use of this technique could be an appropriate alternative method to classic infiltration anesthetic techniques in children and adults [20]. Wood compared intraosseous and infiltration anesthetic techniques for changes in heart rate and serum concentrations of the drug in 2005. For both techniques lidocaine 2% with epinephrine 1/100000 was used. Pulse oximetery was used to assess heart rate and blood samples were taken to check the amount of lidocaine in the serum. Results showed significant changes in HR for intraosseous compared to the infiltration technique but in the evaluation of lidocaine in serum, no significant difference was found between the two methods [21].


#### **Figure 7.** Intraligamentary (PDL) technique

numbness of the lips and tongue and an atraumatic technique. Contraindications for this method are infection and severe inflammation at the injection area. In this technique, first, a point is recorded distal to the teeth in 2 mm apical to confluence of two lines consisting of a horizontal line from the gingival margin and a vertical line from the interdental papillae. The perforation of the soft tissue and bone is done at this point and the anesthetic drug is injected into the cancellous bone. In this method, depending on the number of teeth ¼ to 1 cartridge is used for the anesthesia. Vasoconstrictors should not be used except where required. The duration of pulpal anesthesia in this technique will be from 15 to 30 minutes [1].Sixon's study in 2008 revealed the effectiveness of this technique as a primary technique. For a total of 181 children and adults, 225 intraosseous injections were done with 4% articaine. The success of this technique was reported to be 95% for primary teeth and 87.9% for permanent teeth and it was shown that the use of this technique could be an appropriate alternative method to classic infiltration anesthetic techniques in children and adults [20]. Wood compared intraosseous and infiltration anesthetic techniques for changes in heart rate and serum concentrations of the drug in 2005. For both techniques lidocaine 2% with epinephrine 1/100000 was used. Pulse oximetery was used to assess heart rate and blood samples were taken to check the amount of lidocaine in the serum. Results showed significant changes in HR for intraosseous compared to the infiltration technique but in the evaluation of lidocaine in serum, no significant difference was found

**2. Intraligamentary technique:** Advantages include minimal anesthetic drug requirements, rapid onset and the lack of tongue and lip numbness. This technique can be used as an adjunct method after a nerve block. Contraindications include infection and primary teeth (due to possible damage to permanent teeth). In this technique, a 27 gauge short needle with its long axis parallel to the tooth is inserted at the mesial or distal of the dental root. If the injection is not possible in the mesial or distal surfaces because of tight proximal contacts, it should be applied into the buccal and lingual surfaces parallel with the long axis of the tooth. The infusion rate must be 0.2 ml over 20 seconds. The duration of anesthesia produced by this method is between 5 to 55 minutes [1]. In a 2005 study on 54 patients in whom IAN block did not provided appropriate anesthesia for treatment, it was found that PDL injection provided successful anesthesia in 56% of patients (30 patients) showed this to be a reliable method [22]. A modified technique is recommended for PDL injection with a needle angle of 30 degrees relative to the longitudinal axis of the tooth and the entrance point in the mesiobuccal and distobuccal area; which is a time-tested

**3. Intraseptal technique:** This method is indicated when there is a need for pain control and hemostasis of soft and hard tissue simultaneously. Infection in the injection area is a contraindication for this technique. The benefits are similar to the previous techniques. The short duration of pulpal anesthesia and the requirement of the numerous tissue punctures are in the context of its disadvantages. In this technique, a short 27-gauge needle is inserted into the center of the interdental papilla. The entrance point is 2 mm below the tip of the papilla and the direction of the needle will be towards the apex of the tooth. The

between the two methods [21].

16 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

method (Figure 7) [23].

angle of the needle in the frontal plane must be 45 degrees relative to the long axis of the tooth. Then 0.2 to 0.4 ml is injected [1] (Figure 8). This technique can be used for anesthesia in the posterior mandible with dense bone and is comparable to the inferior alveolar nerve block injection [24].

#### **Figure 8.** Intraseptal technique

**4. Intrapulpal technique:** In the absence of adequate anesthesia methods, this method can be used for the endodontic treatment of teeth. The benefits consist of fast onset, mild side effects and the lack of lip and tongue numbness. A major disadvantage is that it requires exposure of the pulp which limits the ability to use this method only in endodontic therapy [1] or in the course of removal of impacted teeth.

