Modulation of orthodontic tooth movement though diet and electrolyte metabolism

• Applicants: Professor Dr. Christian Kirschneck; Dr. Agnes Schröder
• Subject Area: Dentistry, Oral Surgery
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 407642414

For orthodontic tooth movement, a mechanical force is applied to a tooth creating pressure and tension zones in the periodontal ligament (PDL), where bone resorption and bone apposition processes take place, thus enabling tooth movement in the direction of force. Despite the importance of orthodontic treatment for patient health, many aspects are yet poorly understood. Since tooth movement is a sterile-inflammatory, immunological process, there are many potential systemic and exogenous influences. In our own preliminary work, the effect of various exogenous modulators on orthodontic tooth movement has already been investigated (strontium ranelate, nicotine, meloxicam). In addition to pharmaceuticals, modulation is also to be expected by certain lifestyle habits such as diet. Among other things, electrolytes such as sodium and potassium are generally consumed in today's society at high, unphysiological quantities as a dietary supplement (for example in finished products). They can therefore exert pharmacological-immunological effects via the electrolyte balance and their local tissue concentration. In our own preliminary work we could show that Na+-rich nutrition leads to Na+ deposition in the skin, which is accompanied by macrophage infiltration. These increasingly express the transcription factor NFAT5 (increased transcription of osmoprotective genes). In preliminary experiments, an increased Na+ concentration in hPDL fibroblasts led to an induction of NFAT5 and genes regarding the remodeling of the extracellular matrix and the RANKL / OPG system. Due to the direct influence of Na+ on the activity of immune cells such as macrophages and hPDL fibroblasts, it can be assumed that the local NaCl concentration in the periodontium could also have an influence on the sterile inflammatory reaction induced by orthodontic tooth movement. However, the role of immunomodulatory properties of electrolytes in this regard has not been studied to date. NaCl could therefore cause an unexpected acceleration or inhibition of orthodontic tooth movement, but also an increase or decrease of undesired associated tooth root resorption, periodontal bone loss or early relapse of the moved teeth towards the initial position. In addition to formulating first preventive recommendations for salt consumption during orthodontic therapy, the exploration of these relationships may also allow targeted use of NaCl as an adjuvant therapeutic. The aim of the proposed project is therefore to investigate the effects of a NaCl-rich / poor diet on orthodontic tooth movement and associated side effects as well as the underlying molecular processes, in particular a possible regulation via NFAT5.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Peter Proff