We believe that a causal relationship exists between proliferative stimulus and increased periodontal ligament (PDL) space.
During orthodontic tooth movement, continuous bone resorption on the compression side and bone apposition on the tension side of the PDL occurs, through a complex multifactorial sequence of biological events, followed by tooth migration toward the compressive side. The orthodontic loading also generates a proliferative stimulus of the PDL that increases the PDL space resulting in major changes in the mechanical properties of the periodontium and tooth stability. , These changes, which are intimately associated with the underlining biological response after orthodontic loading, facilitate the atraumatic extraction of a donor’s tooth. , We had demonstrated in a previous article that a minimum of a 4-week duration of orthodontic preloading is sufficient to adequately enhance the PDL and ease tooth extraction; both outcomes may be beneficial for tooth autotransplantation.
Currently, we are conducting clinical studies with autotransplanted teeth that had been stimulated and uprighted with orthodontic preloading. The results obtained are promising and will be reported.
Consequently, we concluded that the preapplication of orthodontic force on human PDL tissue enhances, increases the PDL space, and reduces the risks of trauma to the PDL during extraction. However, the evaluation of the PDL proliferation was performed on the basis of the percentage of area stained with toluidine blue on the root surface. Further studies assessing the quality and thickness of the remaining PDL are necessary.
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