What is the primary nerve responsible for sensation in the lower teeth and gums?

The primary nerve responsible for sensation in the lower teeth and gums is the Inferior Alveolar Nerve. Here are the steps to understand this:

1. The nervous system in our body is responsible for sensation. It is divided into the central nervous system (brain and spinal cord) and the peripheral nervous system (all other nerves in the body).

2. The peripheral nervous system is further divided into cranial nerves (which come directly from the brain) and spinal nerves (which come from the spinal cord).

3. One of these cranial nerves is the Trigeminal Nerve, also known as Cranial Nerve V. This nerve is responsible for sensation in the face and motor functions such as biting and chewing.

4. The Trigeminal Nerve has three divisions: the Ophthalmic Nerve (V1), the Maxillary Nerve (V2), and the Mandibular Nerve (V3).

5. The Mandibular Nerve (V3) is responsible for sensation in the lower part of the face, including the lower teeth and gums.

6. One of the branches of the Mandibular Nerve is the Inferior Alveolar Nerve. This nerve provides sensation to the lower teeth and gums.

So, the primary nerve responsible for sensation in the lower teeth and gums is the Inferior Alveolar Nerve, which is a branch of the Mandibular Nerve, a division of the Trigeminal Nerve.