Periodontal Membrane in Teeth Structure and Role

The periodontal membrane is also known as a periodontal ligament.  Periodontal membranes are fleshy tissues present inside the tooth and tooth sockets. These help to hold the tooth, attach the adjacent teeth with it and resist the stress that occurs during chewing food. Periodontal membrane develops from the follicular sac, which is present around the embryonic tooth during the growth of the tooth. The periodontal fiber contains sensory nerves and blood vessels. This helps to sense the pain, touch, and proprioceptive sensation of the tooth, then the nervous system transmits the necessary information to coordinate muscle activity such as mastication and swallowing.  

[Image will be Uploaded Soon]

Structure of Periodontal Membrane 

Periodontal Ligament consists of loose connective tissue, oxytalan fiber, principal fibers, loose connective tissues, blast & clast cells, and cell rest of Malassez. The structure of each part of the periodontal membrane is listed below. 

Alveolodental Ligament 

The alveolodental ligament fiber group consists of five subgroups. They are, namely, alveolar crest, oblique, horizontal, apical, and inter radicular on multirooted teeth. These fibers help the tooth to maintain stability during the natural compression force, which usually occurs during the chewing, and remain connected with the bones. Sharpey fibers or alveolar bone or cementum are present at the end principal fibers. 

[Image will be Uploaded Soon]

Transseptal Fibers 

The transseptal fibers form an interdental ligament by extending over the alveolar bone crest and get bound in the cementum, which is adjacent to the teeth. These fibers take responsibility for the teeth’ alignment. Transseptal fibers do not have an osseous attachment so, they may be considered as belonging to the gingival tissue. 

Loose Connective Tissue 

The loose connective tissue has an extracellular matrix, cells, fibers, nerves, and blood vessels. The extracellular compartments are embedded in intercellular substances that consist of Type 1, 3, and 5 collagen fiber bundles. Periodontal ligament collagen fibers are classified according to their location and orientation of the tooth. Here,  defence cells, fibroblast, and undifferentiated mesenchymal cells are also present along with the loose connective tissue. 

Cell Rest of Malassez

Cell rest of malassez have groups of epithelial cells, which are located near the matured periodontal ligament. These are formed after the disintegration of the Hertwig epithelial root sheath and the formation of the root. They form a network around the entire tooth. Cell rest of malassez may remain as a cause for cyst formation. 

Oxytalan Fibers 

Periodontal ligament contains oxytalan fibers, which have natural elasticity. It enters into the cementum and runs in two different directions. That is oblique to the root surface and parallel to the root surface. 

Functions of Periodontal Membrane

The periodontal ligament fibers are found only between the tooth root and adjacent bone. Further, it does not support the outer gum tissues. The complex nature of the periodontal ligament tissues allows the tooth to chew the food and to withstand the pressure that arises during the grinding or clenching. Major periodontal ligament function is to allow the tooth to withstand force from habits such as grinding. When the tooth begins to move or loosen, the periodontal ligament starts to enlarge. Once the force on the tooth decreases, this layer starts to heal and reduce the tooth mobility. 

Orthodontic movement can support the treatment of periodontal ligament, which occurs due to tooth eruption and tooth movement.  If the tooth is directly connected with the bone, the breakdown of the periodontal area could not cause the movement of the bone. Because it hosts the tooth in its socket.  If the tooth was not connected with the bone, then the tooth can be extracted without removing any jawbone. 

List of Periodontal Ligament Function

Support: The periodontal ligament fibers allow the teeth to get attached to the surrounding alveolar bone with the cementum. The periodontal ligament fibers can absorb and transmit the force between the teeth and alveolar bone. 

Nutritive: PDL ensures the health and connectivity of the surrounding cells. It transmits the nutrients through gingival vessels, perforating vessels, and apical blood vessels. 

Sensory: PDL are heavily innervated, the PDL involves mechanoreception, nociception, and reflexes.

Remodeling: It contains Progenitor cells, which are differentiated from osteoblasts. These cells can help for physiological maintenance and repair of the alveolar bone. 

Periodontal Risk Factors 

A person who has the following risk factors has a high possibility to be a victim of periodontal disease. 

Age: According to the research, about 70% of the oldest people are suffering from periodontal disease. It may result in bleeding gums and weakening teeth. 

Smoking / Tobacco Use: Usually tobacco is causing serious illnesses such as cancer, lung disease, and heart disease. It also leads to many other health issues. This also increases the risk of getting affected by periodontal disease. 

Genetics: A person with genetic gum disease or aggressive oral care habits are more likely to be a victim of periodontal disease. Those require lifetime treatment to maintain their teeth health. 

Stress: Usually stress causes many serious disorders like hypertension, cancer..etc. It also increases the risk factor for periodontal disease. Researchers found that stress causes more infections to the body along with periodontal diseases.

Medication: Oral medications will affect health. It also increases the risk of periodontal fibers diseases. Some medications like contraceptives, antidepressants, and certain heart medicines increase the risk factors. 

Poor Nutrition and Obesity:  A diet with poor nutrients will defect the whole immune system of the human body. So, the human body cannot fight against infections or diseases attacking it. In addition, obesity improves the risk of periodontal ligament fiber infections. 

Clenching or Grinding of Teeth: The force acting on the teeth, while clenching and grinding the teeth can also damage the periodontal tissues 

Other Diseases: Some cardiovascular diseases, rheumatic arthritis, diabetes, and some other diseases can also worsen the periodontal tissues and improve the risk of it.