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Periodontal Ligament: What Is It?

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Medically Reviewed By Colgate Global Scientific Communications

The periodontal ligament (PDL) is the soft tissue union between your teeth and the bone. Many people think teeth are held in by the bone and gum tissue, but the truth is that the PDL is what really holds your teeth in place. The periodontal ligament is made of various collagen types and has a neurovascular component that is extremely narrow yet very complex. Although called a ligament, your PDL is not like the ligaments that surround an articulating joint. However, this special ligament plays a crucial function in your overall oral health.

What Does the Periodontal Ligamen (PDL) Do?

The periodontal ligament does not support the outer gum tissues and is only found between the root part of the tooth and the adjacent bone. This complex tissue allows the tooth to function under the load of chewing and absorb excess pressure from clenching and grinding. The ligament is also involved in tooth movement and aids in the eruption of the tooth.

The PDL is also what makes orthodontic tooth movement possible. If the tooth were directly connected to the bone, the tooth would function similarly to a dental implant and not be able to move. Because the tooth is held in the socket by the periodontal ligament and not a direct bone-to-tooth interface, it can usually be extracted without removing any significant areas of the jawbone.

The periodontal ligament also allows the tooth to adapt to forces from tooth grinding (also known as bruxism) or other jaw clenching habits. The ligament can enlarge and allow the tooth to become loose. Once the excessive forces on the tooth are reduced, the PDL will heal, and tooth mobility will decrease.

The Periodontal Ligamen and Overall Oral Health

Advanced gum disease can lead to the destruction of bone and the loss of the periodontal ligament. In areas where the ligament has been lost, the adjacent bone is no longer attached to the tooth and cannot provide any support. The PDL is also prone to periodontal inflammation and cannot be easily regenerated. Even with a bone graft placement, if the periodontal ligament is not restored in the area, the bone graft may not work.

The periodontal ligament serves a quiet but meaningful role within your mouth. It's important to make sure that you're practicing good oral hygiene practices by brushing twice a day and cleaning between your teeth daily. This will help you prevent gum disease and keep your periodontal ligaments strong and healthy as they support your teeth.

Oral Care Center articles are reviewed by an oral health medical professional. This information is for educational purposes only. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your dentist, physician or other qualified healthcare provider. 

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