Specific terms are used to describe the nature of tooth agenesis. Hypodontia is most frequently used when describing the phenomenon of congenitally missing teeth. Many other terms to describe a reduction in the number of teeth appear in the literature: oligodontia, anodontia, aplasia of teeth, congenitally missing teeth, absence of teeth, agenesis of teeth and lack of teeth. The term hypodontia is used when one to six teeth, excluding third molars, are missing, and oligodontia when more than six teeth are absent (excluding the third molars). The long‐term management of hypodontia in the aesthetic zone is a particularly challenging situation. Although there are essentially two distinct approaches to manage this problem, that is space closure or opening for prosthetic replacements, implant or autotransplantation. These patients often manifest with many underlying skeletal and dental problems and a multidisciplinary approach for management of this condition is recommended. Two treatment approaches including space closure and space reopening are described in details in this chapter.
Part of the book: Dental Anatomy
Tooth movement by orthodontic force application is dependent on remodeling in periodontal ligament and alveolar bone, involving the activation of complex cellular and molecular mechanisms correlated with several macro- and microscopic biological changes. The orthodontic process involves the activation of many complex cellular and molecular mechanisms mediated by the release of chemical substance cascades by many cells of the periodontium. Mainly during the early stage of application of orthodontic forces, an inflammatory process can occur in the periodontium as a physiological response to the tissue stress. Several potential biomarkers of the biological alterations after an orthodontic force application expressing bone resorption and formation, periodontal ligament changes, and vascular and neural responses, may be detected. The appropriate choice of the mechanical force to achieve the highest rate of tooth movement in the shortest time of treatment avoiding adverse consequences is a primary objective of a specialist. Thus, an insight into the biological phenomena occurring during the orthodontic therapies by evaluating these biomarkers may be quite relevant for the clinicians. In this chapter, two models of study, i.e., mice and men, were used to describe the clinical usefulness of some biomarkers in orthodontics.
Part of the book: Periodontitis