periodontaaliligamentti

Periodontaallligamentti, often abbreviated as PDL, is a specialized connective tissue that surrounds the root of a tooth and connects it to the alveolar bone. It is a crucial component of the periodontium, the functional unit that supports the teeth. The PDL is a dynamic tissue, playing a vital role in tooth support, proprioception, and maintenance of the gingiva and alveolar bone.

Histologically, the PDL is composed of collagen fibers, fibroblasts, blood vessels, nerves, and ground substance. The principal collagen fibers, known as Sharpey's fibers, insert into the cementum of the tooth root and the alveolar bone, forming a sling-like structure that resists occlusal forces. Fibroblasts are the most abundant cells in the PDL and are responsible for synthesizing and remodeling the extracellular matrix, including collagen. The vascularity of the PDL is essential for nutrient supply and waste removal, as well as for inflammatory and repair processes. Nerve fibers within the PDL provide sensory information regarding touch, pressure, and pain, contributing to proprioception and masticatory reflexes.

The PDL acts as a shock absorber, dissipating occlusal forces and protecting the tooth and bone from damage. It also plays a critical role in tooth eruption and orthodontic tooth movement by facilitating bone remodeling. Furthermore, the PDL contributes to the health and integrity of the surrounding gingiva and alveolar bone through its metabolic and regenerative functions. Diseases affecting the periodontium, such as periodontitis, often involve damage to the PDL, leading to tooth mobility and eventual loss.