Creative Non-Surgical Bone Augmentation in the Treatment of Ankylosis and Deep Impaction
Conventional biomechanical principles mainly focused on how to move tooth/teeth that are already erupted, which normally requires two-dimensional tooth movement in each spatial plane. In contrast, pathologic conditions during the formation and development of dentition such as impaction and/or non-eruption may lead to various three-dimensional tooth and alveolar bone relationships due to the undesired migration of adjacent teeth, when left untreated. Surgical exposure and orthodontic forced eruption has been a routine practice for impacted tooth. However, the forced eruption of impacted tooth may demand biological consideration, because the eruption of a tooth, unlike the regular tooth movement, is under stage-specific regulation. Hence a strategic and individualized treatment planning is crucial, starting from the differential diagnosis of ankyloses. Using the bone-borne miniscrews, one may try therapeutic diagnosis whether it is indeed ankylosed. Then the 'best' treatment plan may be found based on 'game theory' considering the individual conditions. This presentation is aimed to propose and summarize essential factors for the predictable treatment of ankylosed and/or impacted tooth with clinical significance, with attention to the (1) biologic factors - depth, angulation, root maturity and age (2) biomechanical factors - three-dimensional localization and application of TADs according to the force-driven approach. The orthodontic treatment overall should be considered a process which facilitate the underlying osteogenic potential of the peri-dental tissue and thereby restore the undesirable alveolar structure during and after the formation of dentition.