Question

MC (Most Common) nerve injured during Submandibular gland surgery?

• A. Lingual nerve
• B. Inferior alveolar nerve
• C. Hypoglossal nerve
• D. Nerve to mylohyoid

Hint:

The nerve that wraps around Wharton's duct is most at risk during submandibular gland excision.

Answer 1

The Correct Option is A

During excision of the submandibular gland, several nerves traverse the operative field. The lingual nerve (branch of the mandibular division of the trigeminal nerve, $V_3$) provides general sensation to the anterior two-thirds of the tongue and carries taste fibres (via chorda tympani) and parasympathetic secretomotor fibres to the submandibular and sublingual glands. Anatomically, the lingual nerve descends between the medial pterygoid and the mandible, then loops under Wharton's duct (submandibular duct) in a characteristic double-loop relationship: the nerve crosses from above the duct laterally, winds beneath it, and crosses back superiorly. This intimate looping around Wharton's duct places the lingual nerve at greatest risk during ligation and division of the duct in submandibular gland surgery. Lingual nerve injury results in ipsilateral tongue numbness, loss of taste (anterior $2/3$), and dry mouth. The hypoglossal nerve (CN XII) supplying intrinsic tongue muscles is the second most vulnerable nerve. Injury to the marginal mandibular branch of the facial nerve (CN VII) causes lower lip weakness. The inferior alveolar nerve lies within the mandibular canal and is rarely at risk. \[\boxed{\text{Lingual nerve}}\]