The periodontium is part of the masticatory system and is made up of the alveolar bone, the root cement and the periodontal ligament, together with the gingiva.
The periodontal ligament It is a component of the periodontium formed of highly vascularized and cellular soft connective tissue that joins the root cement of the tooth with the lamina dura of the alveolar bone of the jaws. It is made up of a set of collagen fibers that surround the root of the tooth. It continues with the connective tissue of the gingiva and connects with the medullary spaces through the vascular ducts of the maxillary bone. It is a space between the bone and the root of the tooth, about 0.3 millimeters. Thanks to this tissue, the teeth are not anchored to the bone like other species of animals.
This tissue develops from a dental sac or follicle, which surrounds the dental germ. It is formed concomitantly with root development and tooth eruption. The collagen fibers that make up the periodontal ligament are modified during the eruption and when adequate occlusal contact is reached, the ligament fibers associate into well-oriented dentoalveolar collagen fibers.
The main fibers of the periodontal ligament are the most important elements of this tissue, they are formed by collagen and are arranged in bundles. The terminal portions of the main fibers are the Sharpey fibers that insert into the cementum and the alveolar bone.. The fibers of the periodontal ligament are arranged in fibers of the alveolar ridge, horizontal fibers, oblique fibers, apical fibers and interradicular fibers (between the roots of the tooth itself).
Four cell types are recognized in the periodontal ligament: connective tissue cells, which include fibroblasts, cementoblasts and osteoblasts, epithelial remnant cells, defense cells, macrophages, neutrophils, lymphocytes, mast cells, and eosinophils. and those related to the neurovascular component.
What are the functions of the periodontal ligament?
The main function of the periodontal ligament is to join the tooth to the alveolar bone. It also has other functions.
The periodontal ligament protects vessels and nerves from injury by masticatory forces, transmits occlusal forces to bone, preserves gingival tissue, and resists the effect of occlusal forces.
In addition, cells of the periodontal ligament are involved in the formation and resorption of bone and cementum that occur in physiological tooth movement and during orthodontic movement.
Finally, this ligament provides nutrients to the cementum, bone and gum through blood vessels, in addition to providing lymphatic drainage.
