Ga-68-Pentixafor and Sodium F-18-Fluoride PET can non-invasively identify and monitor the dynamics of orthodontic tooth movement in mouse model

Ziel/Aim Inflammation and calcification are two main processes during tooth movement, which are initiated by pressure-derived-necrosis and bone remodelling, respectively. The aim of this study is to assess the ability of Ga-68-Pentixafor and Sodium F-18-Fluoride (Na[F-18]F) to monitor the dynamics of orthodontic tooth movement in an established mouse model.

Methodik/Methods An orthodontic appliance consisting of a Nickel-Titanium-alloy coil spring was implanted on the left maxilla of C57BL/6 mice according to a modified previously described method (1). All mice were scanned using a small animal PET/CT on week 1, 3, and 5 post-implantation, with 24h between the two tracers (i.e., Ga-68-Pentixafor was imaged on days 4, 18, and 32, while Na[F-18]F on days 5, 19, and 33). Animals that were taken out of the experiment for ethical reasons were used for interim histological assessments of the periodontal ligament. Alternatively, they were finalised at the end of the last PET/CT scan.

Ergebnisse/Results Both tracers showed an increased uptake in the region of interest (left superior molar region) compared to the contra-lateral side, taken as a background reference. Ga-68-Pentixafor has a stabile uptake within the 5-week trial (TBR=1,8±0,5, 2,0±0,7, and 2,9±0,2 in week 1, 3, and 5, respectively), suggesting a maintenance of inflammatory markers. Na[F-18]F showed an increase in uptake during the trial (TBR=1,78±0,35, 2,1±0,5, and 3,2±0,2 in week 1, 3, and 5, respectively), indicating an intensification of bone remodelling after implantation. Using interim and end-of-experiment histological assessments, CXCR-4 positive cells were found in the periodontal ligament of the region of interest, bone remodelling stainings showed an increased turnover [1].

Schlussfolgerungen/Conclusions In a model of orthodontic tooth movement, Ga-68-Pentixafor and Na[F-18]F can efficiently detect and monitor the dynamics of the periodontal remodelling and allows a time dependent identification of orthodontic tooth movement.

Publikationsverlauf

Artikel online veröffentlicht:
14. April 2022

• Literatur/References

• 1 Ong et al. Angle Orthod 2000; Apr 70 (02) 118-25