Bisphosphonates and orthodontic treatment – a literature review

More and more adult patients decide to start orthodontic treatment. Therefore, it poses a challenge to orthodontists, not only because such treatment is mostly interdisciplinary, but also because of patients' systemic diseases. Many groups of commonly used chemotherapeutics can affect orthodontic treatment – and bisphosphonates are one of them.

Aim
Based on the available literature, the paper aims to discuss the impact of bisphosphonate therapy on orthodontic treatment and its potential future use.

Material and methods
The PubMed and Medline databases and the following keywords: bisphosphonates, orthodontic treatment and tooth movement were used to prepare the review. Literature was supplemented with publications from reviewed journals not included in the PubMed database.

Results
It was observed that in patients treated with bisphosphonates tooth movements were slower under the influence of an applied orthodontic force, crown tipping was predominant compared to axial displacement (bodily movement) and; moreover, it was difficult to close post-extraction spaces. Animal studies have shown that bisphosphonates can inhibit root resorption during orthodontic treatment, provide anchorage enhancement after local administration and reduce the risk of microimplant disintegration.

Conclusions
Orthodontists should be aware of potential difficulties when treating patients taking BPs and plan their actions accordingly so as not to expose patients to possible complications. Currently, studies are performed on small groups of animals – mainly mice and rats, and the duration of measurements is mostly less than 21 days. Therefore to increase the predictability and reliability of outcomes, a longer follow-up period should be introduced, the sample size should be increased, and studies on higher mammals are needed.