Supraperiosteal injection (commonly known as local infiltration) is indicated whenever dental procedures are confined to a localized area in either the maxilla or mandible. The terminal endings of the nerves innervating the region are anesthetized. The indications are pulpal anesthesia of all the maxillary teeth (permanent and primary), mandibular anterior teeth (primary and permanent) and mandibular primary molars when treatment is limited to one or two teeth. It also provides soft tissue anesthesia as a supplement to regional blocks. The contraindications are infection or acute inflammation in the injection area and in areas where dense bone covers the apices of the teeth, i.e., the permanent first molars in children. It is not recommended for large areas due to the need of multiple needle insertions and the necessity to administer larger total volumes of local anesthetic that may lead to toxicity.
Local Infiltration for Mandibular Molars
A number of studies have reported on the effectiveness of injecting local anesthetic solution in the mucobuccal fold between the roots of the primary mandibular molars. When comparing the effectiveness of mandibular infiltration to mandibular block anesthesia, it was generally agreed that the two techniques were equally effective for restorative procedures, but the mandibular block was more effective for pulpotomies and extractions than mandibular infiltration. The mandibular infiltration should be considered in situations where one wants to perform bilateral restorative procedures without anesthetizing the tongue. Bilateral anesthesia of the tongue is uncomfortable for both children and adults.
Local Infiltration for Mandibular Incisors
The indications for mandibular incisor infiltration are:
If quadrant treatment is planned involving posterior and anterior teeth, mandibular infiltration is necessary to anesthetize the terminal ends of the inferior alveolar nerves that cross over the midline from the contralateral quadrant.