In what situation is it appropriate to use an infiltration instead of a nerve block for anesthesia?

Using infiltration anesthesia in children under 6 years old is appropriate due to several factors related to their anatomy and the technique's effectiveness. The maxilla in young children is thinner and has a more favorable response to local anesthetics administered via infiltration. Infiltration generally provides sufficient anesthesia for maxillary teeth because the required volume of anesthetic can diffuse readily through the bone, leading to effective anesthesia of the targeted teeth.

In contrast, while infiltration can be used in adults for maxillary teeth, the option mentions exclusively using it in this context. For lower molars in adults and mandibular anesthesia, a nerve block is typically necessary due to the denser bone structure that inhibits anesthetic diffusion. Thus, it is crucial to consider age and anatomical differences when deciding on the appropriate local anesthetic technique, ensuring effective and safe outcomes for pediatric patients.