Odontogenic cysts are a group of common pathological lesions of the jaw. Typically, they can be found randomly on X-rays as round benign lesions. However, some of them can behave aggressively with a tendency toward malignancy. Among odontogenic cysts with benign pathology, up to 60% of all jaw cysts are radicular cysts, which originate from root canal infection. Pathogenesis involves the interaction between osteoblasts, osteocytes, and osteoclasts as well as the expression of RANK-RANKL/OPG signaling system. Furthermore, collagenases (e.g., MMPs) are expressed in epithelial lining of the cyst. Among odontogenic cysts with potentially aggressive behavior, odontogenic keratocysts (OKCs) have a high rate of recurrence and very debatable treatment options; they can be associated with Gorlin syndrome. Keratocysts have developmental origin and show variability in their gene expression profiles. Their etiology is closely related to genetic factors, especially mutations in different members of Shh signaling pathway, including PTCH gene.
Part of the book: Gene Expression and Control
Dentoalveolar trauma is considered an emergency condition and is challenging for every dentist. As primary and permanent teeth may suffer repercussions from an injury, a therapist must be mindful of which situations the use of splinting methods is required. In dentistry, a splint is a rigid or flexible device with the function of supporting, protecting, and immobilizing teeth that have been weakened (endodontically, periodontally), traumatically injured, replanted, or fractured. Generally, splinting is not recommended for primary teeth injuries such as luxation and avulsion. In permanent dentition, splint appliances are indicated for periodontal injuries, such as subluxation, luxation and avulsion, and hard tissue injuries such as class IV root fractures. Nowadays, there are many appliances that may be used for immobilization of traumatized teeth. Since this issue may sometimes be confusing for dental practitioners, this chapter deals with splint classification (rigid and flexible), the basic characteristics of splints, the indications, and methods of application.
Part of the book: Maxillofacial Surgery and Craniofacial Deformity