<abstract xmlns="http://www.w3.org/1999/xhtml">

<italic>Background:</italic> It is hypothesised that osteoprotegerin (OPG), as an osteoclast antagonist, may offer molecular control over the process of orthodontic root resorption. Previous work investigating OPG in a rat periodontal ligament (PDL) ankylosis model found no inhibitory effect on osteoclasts and odontoclasts when given at a recommended dosage of 2.5 mg/kg. It was considered that traumatically-induced PDL inflammation produces mediators and cytokines with the ability to stimulate clast cell differentiation and counter the effects of OPG.
<italic>Aims:</italic> The present study investigated the presence of Tumour Necrosis Factor Alpha (TNF-α) and its receptor Tumour Necrosis Factor Receptor 1 (TNFR1) in a PDL sterile inflammatory model.
<italic>Methods:</italic> Dry ice was applied for 15 minutes to the upper right first molar crown of eighteen, 8-week-old, male Sprague-Dawley rats of which 9 were injected with OPG at a dose of 2.5 mg/kg of body weight at the time of freezing. After 7 days, the rats were sacrificed and each maxilla processed for immunohistochemical identification of TNF-α and TNFR1.
<italic>Results:</italic> Results showed the presence of root resorption in varying amounts and locations in both experimental and control rats. Reparative processes appeared greater in the OPG-treated rats, often with the presence of an ankylotic union. Immunolabelling showed the presence of TNF-α and TNFR1 in the sterile inflammation located mainly in the interradicular PDL area. More definitive labelling appeared in OPG-treated rats.
<italic>Conclusion:</italic> The results indicated that TNF-α, and its receptor TNFR1, by their presence, may modify OPG effectiveness by offering an alternative pathway for osteoclast formation, which counters the anti-resorptive effects of OPG.
</abstract>

Background: It is hypothesised that osteoprotegerin (OPG), as an osteoclast antagonist, may offer molecular control over the process of orthodontic root resorption. Previous work investigating OPG in a rat periodontal ligament (PDL) ankylosis model found no inhibitory effect on osteoclasts and odontoclasts when given at a recommended dosage of 2.5 mg/kg. It was considered that traumatically-induced PDL inflammation produces mediators and cytokines with the ability to stimulate clast cell differentiation and counter the effects of OPG.
Aims: The present study investigated the presence of Tumour Necrosis Factor Alpha (TNF-α) and its receptor Tumour Necrosis Factor Receptor 1 (TNFR1) in a PDL sterile inflammatory model.
Methods: Dry ice was applied for 15 minutes to the upper right first molar crown of eighteen, 8-week-old, male Sprague-Dawley rats of which 9 were injected with OPG at a dose of 2.5 mg/kg of body weight at the time of freezing. After 7 days, the rats were sacrificed and each maxilla processed for immunohistochemical identification of TNF-α and TNFR1.
Results: Results showed the presence of root resorption in varying amounts and locations in both experimental and control rats. Reparative processes appeared greater in the OPG-treated rats, often with the presence of an ankylotic union. Immunolabelling showed the presence of TNF-α and TNFR1 in the sterile inflammation located mainly in the interradicular PDL area. More definitive labelling appeared in OPG-treated rats.
Conclusion: The results indicated that TNF-α, and its receptor TNFR1, by their presence, may modify OPG effectiveness by offering an alternative pathway for osteoclast formation, which counters the anti-resorptive effects of OPG.

The presence of TNF-α and TNFR1 in aseptic root resorption. A preliminary study

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

{"article-title":"The presence of TNF-α and TNFR1 in aseptic root resorption. A preliminary study"}

Background: It is hypothesised that osteoprotegerin (OPG), as an osteoclast antagonist, may offer molecular control over the process of orthodontic root...

The presence of TNF-α and TNFR1 in aseptic root resorption. A preliminary study

Published Online: Aug 01, 2023

Page range: 102 - 109

Received: Dec 01, 2010

Accepted: Aug 01, 2011

DOI: https://doi.org/10.2478/aoj-2011-0013

© 2011 Linda Curl et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.