Which tissues are anesthetized by the MSA nerve block besides pulpal anesthesia?

Which tissues are anesthetized by the MSA nerve block besides pulpal anesthesia?

• A. Lingual gingiva of incisors
• B. Buccal periodontal tissues and overlying bone of the premolars
• C. Palatal mucosa of canines
• D. Inferior alveolar muscle

Answer: (B)

The middle superior alveolar block yields anesthesia to the buccal periodontal tissues and the overlying buccal bone in the premolar region, in addition to pulpal anesthesia. This happens because the middle superior alveolar nerve supplies the buccal gingiva and periosteum of the premolars (and the buccal bone over them) as it travels near the roots. It does not affect palatal mucosa (that’s supplied by the greater palatine and nasopalatine nerves) or the lingual tissues, and it wouldn’t numb mandibular muscles (that’s the domain of the inferior alveolar block). So, the tissues anesthetized besides the premolar pulps are the buccal periodontal tissues and the overlying buccal bone of the premolars.

The middle superior alveolar block yields anesthesia to the buccal periodontal tissues and the overlying buccal bone in the premolar region, in addition to pulpal anesthesia. This happens because the middle superior alveolar nerve supplies the buccal gingiva and periosteum of the premolars (and the buccal bone over them) as it travels near the roots. It does not affect palatal mucosa (that’s supplied by the greater palatine and nasopalatine nerves) or the lingual tissues, and it wouldn’t numb mandibular muscles (that’s the domain of the inferior alveolar block). So, the tissues anesthetized besides the premolar pulps are the buccal periodontal tissues and the overlying buccal bone of the premolars.