Studies when patients are asked to list the most important factors used when selecting a dentist, the 2 most important are: (1) a dentist who does not hurt and (2) a painless injection.
There is a trend among dentists toward the use of smaller-diameter needles on the assumption that they are less traumatic to the patient than larger-diameter needles. However, studies dating back to 1972 show this assumption to be unwarranted.4–9 Hamburg4 reported that patients are unable to differentiate among 23-, 25-, 27-, and 30-gauge needles. Fuller and colleagues5 reported no significant differences in the perception of pain produced by 25-, 27-, and 30-gauge needles during inferior alveolar nerve blocks in adults
To prevent accidental intravascular injection, aspiration must be performed before the deposition of any significant volume of local anesthetic.
Posterior Superior Alveolar
The posterior superior alveolar (PSA) injection will anesthetize the maxillary molars except for the mesiobuccal aspect of the first molar
Middle Superior Alveolar
The middle superior alveolar (MSA) injection will anesthetize the mesiobuccal aspect of the maxillary first molar, both premolars, PDL, buccal bone, and periosteum, along with the soft tissue lateral to this area
Anterior Superior Alveolar
The ASA injection will anesthetize the PDL, alveolar bone, periosteum, buccal soft tissue, and teeth from the canine to the midline
The greater palatine (GP) injection will anesthetize the tissues of the hard palate from its most distal aspect, anteriorly to the distal of the canine, and laterally to the midline
The nasopalatine (NP) injection will anesthetize the tissues of the palatal aspect of the premaxilla.
The inferior alveolar (IA) injection will anesthetize the mandibular teeth from the third molar to the midline, the buccal soft tissue from the premolars anteriorly, the body of the mandible, the periosteum, the PDL, and the skin and subcutaneous tissues of the chin and lower lip, all on the ipsilateral side.
The lingual nerve block will anesthetize the lingual gingiva, floor of the mouth, and tongue from the third molar anteriorly to the midline.
The buccal injection will anesthetize the buccal soft tissue lateral to the mandibular molars.
The entire maxillary division of the trigeminal nerve is anesthetized from either of 2 intraoral approaches, but most frequently the second division (V2) is approached via the GP canal.