A central incisor with a lingual root surface periodontal defect would be treated with which injection?

• A. Nasopalatine
• B. Greater Palatine
• C. Infraorbital
• D. Inferior Alveolar

Answer: (A)

When treating a lingual root surface defect on a maxillary central incisor, you want to numb the palatal tissues that surround the anterior teeth. The nerve that provides sensation to the palatal mucosa and gingiva of the maxillary front teeth (including the central incisors) runs through the incisive foramen and is the nasopalatine nerve. An injection near the incisive foramen—the nasopalatine nerve block—follows this pathway and anesthesia the palatal aspect of the anterior maxillary region, allowing access and instrumentation of the lingual root surfaces with less patient discomfort.

The other injections target different areas: the greater palatine block anesthetizes the posterior palate and posterior teeth; the infraorbital block covers a broader region including some of the maxillary anterior teeth and facial tissues but does not specifically numb the anterior palatal gingiva needed for focusing on the lingual aspect of the central incisor; and the inferior alveolar block is for mandibular teeth. Thus, for a lingual root surface defect in the central incisor, the nasopalatine injection is the most appropriate.