Tooth Pulp Function and Inflammation

Tooth pulp is the most vital part of the tooth, originating in the center of the tooth, underneath the enamel layer (the top layer) and the dentin layer (the second layer), in the pulp chamber. The shape of a pulp chamber varies based on the size of the tooth itself.

Tooth pulp is soft and consists of living blood vessels, connective tissue, and large nerves. Also commonly referred to as the nerve, the pulp branches out and continues down each root through the canals of the tooth and stops just shy of the apex, or tip, of the tooth.

You can have up to 52 total different pulp organs: 32 of the pulp organs can be found in your permanent teeth and 20 can be found in your primary teeth, also known as baby teeth. The pulp found in primary teeth is lost along with the teeth when they fall out or are removed from your mouth.

Role and function of tooth pulp
Illustration by Brianna Gilmartin, Verywell

Functions of Tooth Pulp

The pulp has several important functions, including:

  • Sensory function: Pain from trauma to the dentin and/or pulp, differences in temperature, and pressure are caused by stimulation of the pulp.
  • Formation of dentin: The pulp is responsible for the formation of dentin. In response to trauma, the pulp forms secondary dentin, also known as reparative dentin.
  • Nourishment: The pulp contains blood vessels that keep blood flowing to help to prevent the tooth from becoming brittle by keeping it moisturized and nourished.

The Role of Dentin

The most important job of tooth pulp is to produce dentin, which is a calcified tissue that serves as the second layer of the tooth, supporting the enamel above it. Dentin is located directly above the pulp chamber, so if your tooth enamel or your gums erode, the dentin becomes exposed. This usually causes pain, especially when you eat or drink something that's hot or cold because the dentin stimulates your tooth pulp or nerve. Composing the majority of the tooth’s structure, dentin is both harder and denser than actual bone and varies in color. It can appear gray or black, but it most typically appears with a yellowish hue.


Painful inflammation of the pulp results in a condition known as pulpitis. Tooth decay is the number one cause of pulpitis, followed by injury. If the inflammation is mild, it may be reversible, but if it's severe, the pulp can die. Pulpitis can also cause an infection at the root of your tooth, known as an abscess. If you have pulpitis, you'll know it because it's extremely painful.

It's important to see your dentist right away if you think you have pulpitis. If you do have an abscess and it's left untreated, the infection can spread to your jaw, sinuses, or even to your brain. Your dentist can do some tests to see if your tooth pulp is able to be saved.

Types of Pulpitis

There are two types of pulpitis:

  • Reversible pulpitis: Treating reversible pulpitis will help pain or sensitivity go away, not swelling. If there is swelling, then it is caused by a periapical problem in the tooth associated with irreversible pulpitis or necrosis of the pulp.
  • Irreversible pulpitis: If your tooth pulp is severely damaged, the only options are for your dentist to perform either a root canal in which the pulp is removed from your tooth, or to remove your tooth completely. If you have a root canal, the pulp will not regenerate inside your tooth, and the tooth becomes non-vital (dead).
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Masthan K. Mystery Inside the Tooth: The Dental Pulp Stem Cells. Journal Of Clinical And Diagnostic Research. 2013. doi:10.7860/jcdr/2013/5379.2984

  2. Goldberg M, Kulkarni AB, Young M, Boskey A. Dentin: structure, composition and mineralization. Front Biosci (Elite Ed). 2011;3:711-35.

  3. Agnihotry A, Thompson W, Fedorowicz Z, Van zuuren EJ, Sprakel J. Antibiotic use for irreversible pulpitis. Cochrane Database Syst Rev. 2019;5:CD004969. doi:10.1002/14651858.CD004969.pub5

  4. Yeo G-S, Kim HY, Kwak E-J, Jung Y-S, Park H-S, Jung H-D. Cavernous sinus thrombosis caused by a dental infection: a case report. Journal of the Korean Association of Oral and Maxillofacial Surgeons. 2014;40(4):195. doi:10.5125/jkaoms.2014.40.4.195

  5. Asgary S, Verma P, Nosrat A. Treatment Outcomes of Full Pulpotomy as an Alternative to Tooth Extraction in Molars with Hyperplastic/Irreversible Pulpitis: A Case Report. Iran Endod J. 2017;12(2):261-265. doi:10.22037/iej.2017.51

Additional Reading
  • American Dental Association. Tooth.
  • Ubertalli JT. Pulpitis. Merck Manual: Consumer Version.

By Shawn Watson
Shawn Watson is an orthodontic dental assistant and writer with over 10 years of experience working in the field of dentistry.