A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as articular ligament, articular larua, fibrous ligament, or true ligament. Other ligaments in the body include the:
Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla or the mandible and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.
Cementum is a specialized calcified substance covering the root of a tooth. The cementum is the part of the periodontium that attaches the teeth to the alveolar bone by anchoring the periodontal ligament.
The periodontal ligament, commonly abbreviated as the PDL, is a group of specialized connective tissue fibers that essentially attach a tooth to the alveolar bone within which it sits. It inserts into root cementum on one side and onto alveolar bone on the other.
Dental alveoli are sockets in the jaws in which the roots of teeth are held in the alveolar process with the periodontal ligament. The lay term for dental alveoli is tooth sockets. A joint that connects the roots of the teeth and the alveolus is called gomphosis. Alveolar bone is the bone that surrounds the roots of the teeth forming bone sockets.
Periodontology or periodontics is the specialty of dentistry that studies supporting structures of teeth, as well as diseases and conditions that affect them. The supporting tissues are known as the periodontium, which includes the gingiva (gums), alveolar bone, cementum, and the periodontal ligament. A periodontist is a dentist that specializes in the prevention, diagnosis and treatment of periodontal disease and in the placement of dental implants.
Regenerative medicine deals with the "process of replacing, engineering or regenerating human or animal cells, tissues or organs to restore or establish normal function". This field holds the promise of engineering damaged tissues and organs by stimulating the body's own repair mechanisms to functionally heal previously irreparable tissues or organs.
The dental follicle, also known as dental sac, is made up of mesenchymal cells and fibres surrounding the enamel organ and dental papilla of a developing tooth. It is a vascular fibrous sac containing the developing tooth and its odontogenic organ. The dental follicle (DF) differentiates into the periodontal ligament. In addition, it may be the precursor of other cells of the periodontium, including osteoblasts, cementoblasts and fibroblasts. They develop into the alveolar bone, the cementum with Sharpey's fibers and the periodontal ligament fibers respectively. Similar to dental papilla, the dental follicle provides nutrition to the enamel organ and dental papilla and also have an extremely rich blood supply.
“Lateral periodontal cysts (LPCs) are defined as non-keratinised and non-inflammatory developmental cysts located adjacent or lateral to the root of a vital tooth.” LPCs are a rare form of jaw cysts, with the same histopathological characteristics as gingival cysts of adults (GCA). Hence LPCs are regarded as the intraosseous form of the extraosseous GCA. They are commonly found along the lateral periodontium or within the bone between the roots of vital teeth, around mandibular canines and premolars. Standish and Shafer reported the first well-documented case of LPCs in 1958, followed by Holder and Kunkel in the same year although it was called a periodontal cyst. Since then, there has been more than 270 well-documented cases of LPCs in literature.
In dentistry, the epithelial cell rests of Malassez (ERM) or epithelial rests of Malassez are part of the periodontal ligament cells around a tooth. They are discrete clusters of residual cells from Hertwig's epithelial root sheath (HERS) that didn't completely disappear. It is considered that these cell rests proliferate to form epithelial lining of various odontogenic cysts such as radicular cyst under the influence of various stimuli. They are named after Louis-Charles Malassez (1842–1909) who described them. Some rests become calcified in the periodontal ligament (cementicles).
Laser-assisted new attachment procedure (LANAP) is a surgical therapy for the treatment of periodontitis, intended to work through regeneration rather than resection. This therapy and the laser used to perform it have been in use since 1994. It was developed by Robert H. Gregg II and Delwin McCarthy.
Guided bone regeneration (GBR) and guided tissue regeneration (GTR) are dental surgical procedures that use barrier membranes to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics or prosthetic restoration. Guided bone regeneration typically refers to ridge augmentation or bone regenerative procedures; guided tissue regeneration typically refers to regeneration of periodontal attachment.
In dentistry, enamel matrix derivative (EMD) is an extract of porcine fetal tooth material used to biomimetically stimulate the soft and hard tissues surrounding teeth to regrow following tissue destruction.
Dental avulsion is the complete displacement of a tooth from its socket in alveolar bone owing to trauma. Normally, a tooth is connected to the socket by the periodontal ligament. When a tooth is knocked out, the ligament is torn.
Regenerative endodontic procedures is defined as biologically based procedures designed to replace damaged structures such as dentin, root structures, and cells of the pulp-dentin complex. This new treatment modality aims to promote normal function of the pulp. It has become an alternative to heal apical periodontitis. Regenerative endodontics is the extension of root canal therapy. Conventional root canal therapy cleans and fills the pulp chamber with biologically inert material after destruction of the pulp due to dental caries, congenital deformity or trauma. Regenerative endodontics instead seeks to replace live tissue in the pulp chamber. The ultimate goal of regenerative endodontic procedures is to regenerate the tissues and the normal function of the dentin-pulp complex.
Tooth mobility is the horizontal or vertical displacement of a tooth beyond its normal physiological boundaries around the gingival area, i.e. the medical term for a loose tooth.
Platelet-rich fibrin (PRF) or leukocyte- and platelet-rich fibrin (L-PRF) is a derivative of PRP where autologous platelets and leukocytes are present in a complex fibrin matrix to accelerate the healing of soft and hard tissue and is used as a tissue-engineering scaffold for endodontics. PRF falls under FDA Product Code KST, labeling it as a blood draw/Hematology product classifying it as 510(k) exempt.
Tooth replantation is a form of restorative dentistry in which an avulsed or luxated tooth is reinserted and secured into its socket through a combination of dental procedures. The purposes of tooth replantation is to resolve tooth loss and preserve the natural landscape of the teeth. Whilst variations of the procedure exist including, Allotransplantation, where a tooth is transferred from one individual to another individual of the same species. It is a largely defunct practice due to the improvements made within the field of dentistry and due to the risks and complications involved including the transmission of diseases such as syphilis, histocompatibility, as well as the low success rate of the procedure, has resulted in its practice being largely abandoned. Autotransplantation, otherwise known as intentional replantation in dentistry, is defined as the surgical movement of a tooth from one site on an individual to another location in the same individual. While rare, modern dentistry uses replantation as a form of proactive care to prevent future complications and protect the natural dentition in cases where root canal and surgical endodontic treatments are problematic. In the modern context, tooth replantation most often refers to reattachment of an avulsed or luxated permanent tooth into its original socket.
Professor Alastair J Sloan is an applied bioscientist and expert in the broad field of mineralised connective tissues, and since January 2020 current head of the Melbourne Dental School, University of Melbourne.
