Periodontal developments during orthodontic tooth movements- review

To point out the biological developments in the periodontal tissues in response to the orthodontic forces applied in solving certain malocclusions.

An electronic search of papers from the PubMed database was conducted with keywords: periodontitis, orthodontics forces, soft tissue changes, bone changes, published in English. Reviews, original clinical trials, and comparative studies are considered. Indirectly are used bibliographic materials quoted in the articles of the authors: Feller L, Yu Gyung Kim, Angelina Gorbunkova and Nan Jiang.

The periodontium as a whole, and especially the periodontal ligament(PDL) and the alveolar bone remain the tissues in which a numerous of pathogenetic mechanisms occur during orthodontic tooth movement. The current literature abounds with data indicating changes in the soft and hard tissue structures of the periodontium. The causes and consequences of the use of orthodontic force on the gingiva (enlargement, invagination and recession) are described as possible conditions for orthodontic tooth movement. Biological changes in the periodontal ligament and alveolar bone are discussed, the activity of osteoblasts and osteoclasts and all responsible mechanisms that participate in each tissue separately are pointed out as well. It has been confirmed that the key effects in the movement of the teeth rely on the activity and differentiation of fibroblasts, osteoblasts and osteoclasts that definitely remodel the bone and correct the present deviations to the desired condition.

Thanks to a number of mediators released from cellular structures (enzymes, MMP-2) and other proinflammatory or osteogenic factors, orthodontic forces stimulate remodeling processes mainly on the periodontal ligament and alveolar bone.